Dynamic multi-carrier uplink operation

Abstract

The wireless device receives one or more radio resource control (RRC) messages indicating a plurality of band pairs for uplink switching and whether each band pair of the plurality of band pairs is configured for uplink switching based on a dual uplink or a switched uplink. The wireless device may also transmit a first uplink over a first band of the first band pair and may transmit a second uplink over a second band of the first band pair. The transmission may be based on the first band pair being configured for dual uplink.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 294,762, filed December 29, 2021, which is incorporated herein by reference in its entirety. Summary of the Invention [Means for solving the problem]

[0002] In this disclosure, various embodiments are presented as examples of how the disclosed technology may be implemented and / or how the disclosed technology may be practiced in environments and scenarios. It will be apparent to those skilled in the relevant art that various changes in form and details can be made without departing from the scope. Indeed, after reading the specification, it will become apparent to those skilled in the relevant art how to implement alternative embodiments. The present embodiments should not be limited by any of the exemplary embodiments. Embodiments of the present disclosure are described with reference to the accompanying drawings. Limitations, features, and / or elements from the disclosed exemplary embodiments may be combined to create further embodiments within the scope of the present disclosure. Figures highlighting features and advantages are shown by way of example only. The disclosed architecture is sufficiently flexible and configurable to be utilized in ways other than those shown. For example, the actions listed in any flowchart may be rearranged or used only optionally in some embodiments.

[0003] Embodiments may be configured to operate as needed. The disclosed mechanisms may be implemented when certain criteria are met, for example, in a wireless device, a base station, a wireless environment, a network, a combination of the above, etc. Exemplary criteria may be based at least in part on, for example, wireless device or network node configuration, traffic load, initial system setup, packet size, traffic characteristics, a combination of the above, etc. Various exemplary embodiments may be applied when one or more criteria are met. Thus, it may be possible to implement exemplary embodiments that selectively implement the disclosed protocols.

[0004] A base station may communicate with a mix of wireless devices. Wireless devices and / or base stations may support multiple technologies and / or multiple releases of the same technology. Wireless devices may have certain capabilities depending on the category and / or capabilities of the wireless devices. When this disclosure refers to a base station communicating with multiple wireless devices, this disclosure may refer to a subset of all wireless devices in the coverage area. For example, this disclosure may refer to multiple wireless devices of a given LTE or 5G release that include a given capability and are located in a given sector of the base station. In this disclosure, multiple wireless devices may refer to selected wireless devices and / or a subset of all wireless devices in the coverage area that perform according to the disclosed methods, etc. There may be multiple base stations or multiple wireless devices in the coverage area that may not comply with the disclosed methods. For example, those wireless devices or base stations are implemented based on older releases of LTE or 5G technology. The present invention provides, for example, the following. (Item 1) 1. A method comprising: By wireless devices, Multiple band pairs for uplink switching, and receiving one or more radio resource control (RRC) messages indicating whether each band pair of the plurality of band pairs is configured for uplink switching based on a dual uplink or a switched uplink; a first band pair of the plurality of band pairs configured for dual uplink; a first uplink transmission over a first band of the first band pair; and transmitting a second uplink transmission over a second band of the first band pair. (Item 2) Item 10. The method of item 1, wherein the one or more RRC messages include configuration parameters of multiple cells indicating the multiple band pairs. (Item 3) 3. The method of claim 2, wherein the configuration parameters indicate a list of band pairs for the uplink switching, the list including the plurality of band pairs. (Item 4) Item 3. The method of item 2, wherein the configuration parameter indicates a cell group including the plurality of cells for carrier aggregation. (Item 5) Item 3. The method of item 2, wherein each of the plurality of cells is within a frequency range of a respective band of a plurality of bands. (Item 6) Item 3. The method of item 2, wherein the configuration parameters indicate at least one uplink carrier associated with each of the plurality of cells. (Item 7) Item 7. The method of item 6, wherein each uplink carrier of a plurality of uplink carriers associated with the plurality of cells is within a frequency range of a respective band of a plurality of bands. (Item 8) 8. The method of claim 5, wherein the plurality of zones comprises at least three zones. (Item 9) 8. The method of claim 5 or 7, wherein the configuration parameters indicate the plurality of band pairs among the plurality of bands. (Item 10) 8. The method of claim 5, wherein each band pair of the plurality of band pairs includes two bands of the plurality of bands. (Item 11) Item 3. The method of item 2, wherein the configuration parameters indicate a plurality of uplink carriers among the plurality of cells for uplink switching. (Item 12) Item 12. The method of item 11, wherein each of the plurality of uplink carriers is within a frequency range of a respective band of a plurality of bands. (Item 13) Item 12. The method of item 11, wherein the configuration parameters further indicate a list of carrier pairs for the uplink switching, the list including a plurality of uplink carrier pairs. (Item 14) Item 14. The method of item 13, wherein each of the plurality of uplink carrier pairs includes two uplink carriers of the plurality of uplink carriers. (Item 15) Item 14. The method of item 13, wherein each of the plurality of uplink carrier pairs is associated with a respective band pair. (Item 16) a first uplink carrier of a first uplink carrier pair is within the first band of the first band pair; and Item 16. The method of item 15, wherein a second uplink carrier of the first uplink carrier pair is within the second band of the first band pair. (Item 17) Item 12. The method of item 11, wherein the configuration parameters include a first parameter for a first uplink carrier of the plurality of uplink carriers that indicates a second uplink carrier as an associated uplink carrier. (Item 18) Item 18. The method of item 17, further comprising determining an uplink carrier pair including the first uplink carrier and the second uplink carrier from among a plurality of uplink carrier pairs. (Item 19) the first band pair includes the first band and the second band; the first uplink carrier is within the first band; the second uplink carrier is in the second band; and 18. The method of claim 17, further comprising determining based on the first uplink carrier being associated with the second uplink carrier. (Item 20) 20. The method of claim 18 or 19, wherein said determining is based on said first parameter. (Item 21) Item 14. The method of item 13, wherein the configuration parameters include a second parameter for a first uplink carrier pair of the plurality of uplink carrier pairs, the second parameter indicating whether the first uplink carrier pair is configured for uplink switching based on a dual uplink or a switched uplink. (Item 22) 22. The method of claim 21, wherein the first uplink carrier pair is associated with the first band pair. (Item 23) 23. The method of claim 22, further comprising determining whether the first band pair is configured with uplink switching based on a dual uplink or a switched uplink based on the second parameter. (Item 24) 24. The method of claim 23, wherein the second parameter indicates that the first band pair is configured for uplink switching based on a dual uplink. (Item 25) 22. The method of claim 21, wherein the second parameter indicates that the first uplink carrier pair is configured for uplink switching based on a dual uplink. (Item 26) the first uplink transmission over a first uplink carrier of the first uplink carrier pair; and 26. The method of claim 25, further comprising determining to transmit the second uplink transmission over a second uplink carrier of the first uplink carrier pair. (Item 27) the first uplink carrier is in the first band of the first band pair; and 27. The method of claim 26, wherein the second uplink carrier is in the second band of the first band pair. (Item 28) Item 3. The method of item 2, wherein the configuration parameters include a third parameter indicating whether the first band pair is configured with uplink switching based on a dual uplink or a switched uplink. (Item 29) 29. The method of claim 28, further comprising determining to transmit the first uplink transmission and the second uplink transmission based on the third parameter indicating that the first band pair is configured with a dual uplink. (Item 30) Item 2. The method of item 1, wherein the first uplink transmission and the second uplink transmission are simultaneous transmissions. (Item 31) 2. The method of claim 1, further comprising: performing simultaneous uplink transmission over the first band and the second band based on a first band pair being configured with a dual uplink. (Item 32) 2. The method of claim 1, further comprising: transmitting the first uplink transmission and the second uplink transmission simultaneously based on a first band pair configured with a dual uplink. (Item 33) Item 1. The method of item 1, wherein the first uplink transmission is via a first uplink carrier in the first band. (Item 34) Item 2. The method of item 1, wherein the first uplink transmission is a first one-port Physical Uplink Shared Channel (PUSCH) transmission. (Item 35) Item 1, wherein the second uplink transmission is via a second uplink carrier in the second band. (Item 36) Item 2. The method of item 1, wherein the second uplink transmission is a second one-port Physical Uplink Shared Channel (PUSCH) transmission. (Item 37) Item 10. The method of item 1, wherein the band is a frequency band comprising a range of frequencies. (Item 38) Item 10. The method of item 1, wherein the transmitter of the wireless device includes a first transmit chain and a second transmit chain. (Item 39) Item 39. The method of item 38, wherein the number of transmit chains of the wireless device is two. (Item 40) Item 1. The method of item 1, wherein for each band pair of the plurality of band pairs, the one or more RRC messages include respective parameters for uplink switching. (Item 41) Item 41. The method of item 40, wherein the parameters for uplink switching include an indication of uplink switching options. (Item 42) Item 42. The method of item 41, wherein the uplink switching options include switched uplink or dual uplink. (Item 43) Item 1. The method according to item 1, wherein the uplink switching based on the dual uplink includes uplink carrier aggregation for simultaneous transmission. (Item 44) Item 10. The method of item 1, wherein the uplink switching based on the switched uplink includes time division multiplexing of the uplink transmission. (Item 45) Item 10. The method of item 1, further comprising transmitting capability information of the wireless device indicating a combination of supported bands including the first band and the second band. (Item 46) 1. A method comprising: By wireless devices, Multiple band pairs for uplink switching, and receiving one or more radio resource control (RRC) messages indicating an uplink switching option for each band pair of the plurality of band pairs, the uplink switching option including a switched uplink or a dual uplink; based on a first uplink switching option associated with a first band pair of the plurality of band pairs indicating a dual uplink; a first uplink transmission over a first band of the first band pair; and transmitting a second uplink transmission over a second band of the first band pair. (Item 47) 1. A method comprising: By wireless devices, a plurality of band pairs, including a first band pair for uplink switching; and receiving one or more radio resource control (RRC) messages indicating the first band pair configured for uplink switching based on a dual uplink; transmitting an uplink transmission over a first band of the first band pair and a second band of the first band pair based on the first band pair being configured for dual uplink. (Item 48) Item 48. The method of item 47, wherein the one or more RRC messages indicate a plurality of uplink carrier pairs, each uplink carrier of the plurality of uplink carrier pairs being within a respective band of a plurality of bands. (Item 49) Item 49. The method of item 48, wherein each uplink carrier pair of the plurality of uplink carrier pairs is associated with a respective band pair. (Item 50) the first uplink transmission over a first uplink carrier in the first band; and 50. The method of claim 49, further comprising transmitting the second uplink transmission over the second uplink carrier in the second band. (Item 51) Item 49. The method of item 48, wherein the plurality of uplink carrier pairs includes a first uplink carrier pair including a first uplink carrier in the first band and a second uplink carrier in the second band. (Item 52) Item 48. The method of item 47, wherein a second band pair of the plurality of band pairs is configured with uplink switching based on a switched uplink. (Item 53) 1. A method comprising: By wireless devices, Multiple uplink carrier pairs for uplink switching; and receiving one or more radio resource control (RRC) messages indicating whether each uplink carrier pair of the plurality of uplink carrier pairs is configured with uplink switching based on a dual uplink or a switched uplink; Based on the first uplink carrier pair of the plurality of uplink carrier pairs being configured as a dual uplink, a first uplink transmission over a first uplink carrier of the first uplink carrier pair; and transmitting a second uplink transmission over a second uplink carrier of the first uplink carrier pair. (Item 54) the first uplink carrier is associated with a first band of a plurality of bands; and Item 54. The method of item 53, wherein the second uplink carrier is associated with a second band of the plurality of bands. (Item 55) Item 55. The method of item 54, wherein the first zone is different from the second zone. (Item 56) Item 55. The method of item 54, wherein the plurality of zones comprises at least three zones. (Item 57) Item 54. The method of item 53, wherein the one or more RRC messages further indicate that uplink switching is configured using the multiple uplink carrier pairs. (Item 58) Item 54. The method of item 53, wherein the one or more RRC messages include an uplink switching configuration parameter indicating the plurality of uplink carrier pairs. (Item 59) Item 54. The method of item 53, wherein each uplink carrier pair of the plurality of uplink carrier pairs includes two uplink carriers of a plurality of uplink carriers. (Item 60) Item 59. The method of item 59, wherein the one or more RRC messages include configuration parameters indicating the multiple uplink carriers. (Item 61) 54. The method of claim 53, further comprising determining that the first uplink carrier pair is configured with a dual uplink for the uplink switching. (Item 62) Item 54. The method of item 53, wherein the one or more RRC messages include at least one parameter indicating whether the first uplink carrier pair supports a switched uplink or a dual uplink for the uplink switching. (Item 63) Item 54. The method of item 53, wherein the one or more RRC messages include a configuration parameter indicating whether each of the plurality of uplink carrier pairs supports a switched uplink or a dual uplink for the uplink switching. (Item 64) Item 54. The method of item 53, wherein the one or more RRC messages include a parameter indicating one or more uplink carrier pairs among the plurality of uplink carrier pairs that support dual uplinks for the uplink switching. (Item 65) Item 54. The method of item 53, wherein the first uplink transmission and the second uplink transmission are simultaneous transmissions. (Item 66) Item 54. The method of item 53, wherein the one or more RRC messages include a parameter indicating that a dual uplink is configured for the uplink switching using the first uplink carrier pair. (Item 67) Item 54. The method of item 53, wherein the first uplink transmission is a one-port transmission. (Item 68) Item 54. The method of item 53, wherein the second uplink transmission is a one-port transmission. (Item 69) Item 54. The method of item 53, wherein the first uplink transmission is a PUSCH transmission. (Item 70) Item 54. The method of item 53, wherein the second uplink transmission is a PUSCH transmission. (Item 71) Item 54. The method of item 53, wherein the first uplink transmission is a two-port transmission. (Item 72) Item 54. The method of item 53, wherein the second uplink transmission is a two-port transmission. (Item 73) Item 54. The method of item 53, wherein the second uplink transmission is performed after the first uplink transmission. (Item 74) 1. A method comprising: switching, by the wireless device, to a first band; determining whether to switch from the second band to a third band based on the switching and based on an association between the first band and a second band. (Item 75) 1. A method comprising: switching, by a wireless device, a first transmit chain of the wireless device to a first band; and determining whether to switch a second transmit chain of the wireless device from the second band to a third band based on the switching and based on an association between the first band and a second band. (Item 76) 76. The method of claim 75, further comprising determining to switch the second transmit chain from the second band to the third band based on the first band not being associated with the second band. (Item 77) Item 77. The method of item 76, wherein the third band is associated with the first band. (Item 78) Item 78. The method of item 77, further comprising receiving an indication of an association between the first band and the third band. (Item 79) Item 79. The method of item 78, wherein the indication includes a radio resource control (RRC) parameter indicating a band pair including the first band and the third band. (Item 80) Item 76. The method of item 75, further comprising determining not to switch the second transmit chain from the second band to the third band based on the first band being associated with the second band. (Item 81) 76. The method of claim 75, further comprising determining to maintain the second transmit chain in the second band based on the first band being associated with the second band. (Item 82) Item 82. The method of item 81, further comprising receiving an indication of an association between the first band and the second band. (Item 83) Item 83. The method of item 82, wherein the indication includes a radio resource control (RRC) parameter indicating a band pair including the first band and the second band. (Item 84) Item 76. The method of item 75, wherein the second transmit chain of the wireless device is associated with the second band. (Item 85) Item 76. The method of item 75, wherein the first zone and the second zone are different zones. (Item 86) Item 76. The method of item 75, wherein each of the first band, the second band, and the third band is a frequency band that includes a range of frequencies. (Item 87) Item 76. The method of item 75, further comprising switching the first transmit chain from a fourth band to the first band. (Item 88) Item 88. The method of item 87, wherein the fourth zone is the second zone. (Item 89) Item 76. The method of item 75, wherein the first zone and the third zone are the same zone. (Item 90) Item 76. The method of item 75, wherein switching a transmit chain to a band includes configuring a transmit antenna to be used for uplink transmission via a carrier on the band. (Item 91) 76. The method of claim 75, further comprising transmitting a first uplink transmission on the first band. (Item 92) 92. The method of claim 91, further comprising transmitting the first uplink transmission on the first band via a first uplink carrier. (Item 93) 93. The method of claim 92, further comprising receiving a scheduling command indicating the first uplink transmission on the first uplink carrier. (Item 94) Item 92. The method of item 91, wherein the first uplink transmission is a one-port uplink transmission. (Item 95) 81. The method of claim 80, further comprising transmitting a second uplink transmission on the second band. (Item 96) 96. The method of claim 95, further comprising transmitting the second uplink transmission on the second band via a second uplink carrier. (Item 97) 97. The method of claim 96, further comprising receiving a second scheduling command indicating the second uplink transmission on the second uplink carrier. (Item 98) Item 96. The method of item 95, wherein the second uplink transmission is a one-port uplink transmission. (Item 99) Item 77. The method of item 76, further comprising transmitting a third uplink transmission on the third band. (Item 100) 100. The method of claim 99, further comprising transmitting the third uplink transmission on the third band via a third uplink carrier. (Item 101) Item 101. The method of item 100, further comprising receiving a third scheduling command indicating the third uplink transmission on the third uplink carrier. (Item 102) Item 99. The method of item 99, wherein the third uplink transmission is a one-port uplink transmission. (Item 103) 1. A method comprising: switching, by a wireless device, a first transmit chain of the wireless device to a first band; and switching a second transmit chain of the wireless device from the second band to a third band associated with the first band based on the switching of the first transmit chain and based on the first band not being associated with a second band. (Item 104) 1. A method comprising: switching, by a wireless device, a first transmit chain of the wireless device to a first band; and maintaining a second transmit chain of the wireless device in the second band based on the switching of the first transmit chain and based on the first band being associated with a second band. (Item 105) 1. A method comprising: switching, by a wireless device, a first transmit chain of the wireless device to a first band; and determining, based on the switching of the first transmit chain and based on the first band being associated with a second band, not to switch a second transmit chain associated with the second band. (Item 106) 1. A method comprising: By wireless devices, a first zone; receiving one or more radio resource control (RRC) messages indicating a plurality of bands including a second band associated with the first band; To decide, switching a first transmit chain of the wireless device from a third band of the plurality of bands to the first band; and determining whether to switch the second transmit chain of the wireless device to the second band based on the switching of the first transmit chain and based on a band among the plurality of bands associated with a second transmit chain of the wireless device. (Item 107) Item 107. The method of item 106, further comprising switching the first transmit chain to the first band based on the determination. (Item 108) Item 107. The method of item 106, further comprising determining to switch the second transmit chain to the second band based on the second transmit chain being configured in a fourth band. (Item 109) Item 109. The method of item 108, wherein the fourth zone and the second zone are different. (Item 110) Item 107. The method of item 106, further comprising determining not to switch the second transmit chain to the second band based on the second transmit chain being configured in the second band. (Item 111) 1. A method comprising: By wireless devices, a first zone; receiving one or more radio resource control (RRC) messages indicating a plurality of bands including a second band associated with the first band; switching a first transmit chain of the wireless device from a third band of the plurality of bands to the first band; determining a second transmit chain of the wireless device associated with the second band based on the switching and based on the second band being associated with the first band; transmitting an uplink transmission over the first band. (Item 112) Item 112. The method of item 111, wherein the switching is in response to a scheduling command indicating the uplink transmission of a first uplink carrier in the first band. (Item 113) Item 112. The method of item 111, further comprising switching the second transmit chain of the wireless device from a fourth band to the second band. (Item 114) Item 114. The method of item 113, wherein switching the second transmit chain is in response to the fourth band being different from the second band. (Item 115) Item 112. The method of item 111, further comprising not switching the second transmit chain. (Item 116) Item 116. The method of item 115, wherein not switching the second transmit chain is in response to the second transmit chain being associated with the second band. (Item 117) Item 112. The method of item 111, wherein the uplink transmission is a one-port uplink transmission. (Item 118) Item 112. The method of item 111, wherein the one or more RRC messages include a first parameter indicating that the second band is associated with the first band. (Item 119) Item 112. The method of item 111, wherein the one or more RRC messages include configuration parameters indicating one or more band pairs, including a first band pair including the first band and the second band. (Item 120) Item 120. The method of item 119, wherein each band pair of the one or more band pairs includes a first band and a second band associated with the first band. (Item 121) Item 120. The method of item 119, wherein the one or more RRC messages include a second parameter indicating that uplink switching based on dual uplink is configured for the first band pair. (Item 122) Item 112. The method of item 111, wherein the one or more RRC messages include a third parameter indicating that uplink switching based on a band pair including the first band and the second band is enabled. (Item 123) 1. A method comprising: determining, by a wireless device, a first transmit chain of the wireless device associated with a first band and a second transmit chain of the wireless device associated with a second band; switching the first transmit chain from the first band to a third band; determining, based on the switching, to associate the second transmit chain of the wireless device with a fourth band, the fourth band being associated with the third band; transmitting an uplink transmission over the third band. (Item 124) Item 124. The method of item 123, wherein the second zone is different from the first zone. (Item 125) Item 124. The method of item 123, wherein the second zone is different from the third zone. (Item 126) Item 124. The method of item 123, wherein the fourth zone is the same as the second zone. (Item 127) Item 124. The method of item 123, wherein the fourth zone is different from the second zone. (Item 128) Item 124. The method of item 123, wherein the first transmit chain is configured in the first band and the second transmit chain is configured in the second band. (Item 129) Item 124. The method of item 123, wherein the switching includes reconfiguring the first transmit chain within the third band. (Item 130) Item 124. The method of item 123, further comprising switching the second transmit chain from the second band to the fourth band. (Item 131) Item 124. The method of item 123, further comprising not switching the second transmit chain out of the second band. (Item 132) Item 132. The method of item 131, wherein the fourth zone is the second zone. (Item 133) Item 124. The method of item 123, further comprising transmitting a second uplink transmission over the fourth band. (Item 134) 1. A method comprising: receiving, by a wireless device, an indication to switch at least one of a plurality of transmit chains of the wireless device to a third band that supports multi-layer transmission; based on the indication of switching to the third band supporting multi-layer transmission; a first transmit chain of the plurality of transmit chains from a first band to the third band; and switching a second transmit chain of the plurality of transmit chains from a second band to the third band. (Item 135) 1. A method comprising: receiving, by the wireless device, a grant indicating uplink switching to a third band supporting multi-tier transmission; based on the grant indicating uplink switching to the third band supporting multi-layer transmission; a first transmit chain of the wireless device from a first band to the third band; and switching a second transmit chain of the wireless device from a second band to the third band. (Item 136) Item 136. The method of item 135, wherein the permission indicates uplink switching between at least one single-layer transmission with one antenna port and a multi-layer transmission with two antenna ports. (Item 137) Item 137. The method of item 136, further comprising transmitting the multi-layer transmission via an uplink carrier on the third band. (Item 138) Item 136. The method of item 135, wherein the grant indicates uplink switching between a first single-layer transmission with one antenna port and a second single-layer transmission with one antenna port. (Item 139) Item 139. The method of item 138, further comprising transmitting the second single-layer transmission via an uplink carrier on the third band. (Item 140) 1. A method comprising: determining, by a wireless device, a first transmit chain of the wireless device associated with a first band and a second transmit chain of the wireless device associated with a second band; switching the first transmit chain from the first band to a third band; switching the second transmit chain of the wireless device from the second band to the third band based on switching the first transmit chain; transmitting an uplink transmission over the third band. (Item 141) 1. A method comprising: determining, by a wireless device, to associate a first transmit chain and a second transmit chain of the wireless device with a first band; switching the first transmit chain from the first band to a second band for a first transmission; switching the second transmit chain from the first band to a third band for a second transmission; transmitting the first transmission over the second band and the second transmission over the third band. (Item 142) 1. A method comprising: By wireless devices, Multiple bands for uplink switching, and receiving one or more radio resource control (RRC) messages indicating whether each band of the plurality of bands can transmit using one transmit chain or two transmit chains; and transmitting a two-port uplink transmission over a first band of the plurality of bands based on the first band being capable of two transmit chains. [Brief explanation of the drawings]

[0005] Some examples of various embodiments of the present disclosure are described herein with reference to the drawings.

[0006] [Figure 1] 1A and 1B illustrate an exemplary mobile communication network in which embodiments of the present disclosure may be implemented.

[0007] [Figure 2] 2A and 2B show the New Radio (NR) user plane and control plane protocol stacks, respectively.

[0008] [Figure 3] FIG. 3 shows an example of services provided between protocol layers of the NR user plane protocol stack of FIG. 2A.

[0009] [Figure 4] Figure 4A shows an example downlink data flow through the NR user plane protocol stack of Figure 2A. Figure 4B shows an example format of a MAC subheader in a MAC PDU.

[0010] [Figure 5] 5A and 5B show the mapping between downlink and uplink logical, transport, and physical channels, respectively.

[0011] [Figure 6] FIG. 6 is an exemplary diagram illustrating RRC state transitions for a UE.

[0012] [Figure 7] FIG. 7 shows an example structure of an NR frame in which OFDM symbols are grouped.

[0013] [Figure 8] FIG. 8 shows an example configuration of slots in the time and frequency domain of an NR carrier.

[0014] [Figure 9] FIG. 9 shows an example of bandwidth adaptation using three configured BWPs for an NR carrier.

[0015] [Figure 10] Figure 10A shows three carrier aggregation configurations with two component carriers, and Figure 10B shows an example of how aggregation cells can be configured into one or more PUCCH groups.

[0016] [Figure 11] Figure 11A shows an example of an SS / PBCH block structure and location, and Figure 11B shows an example of a CSI-RS mapped to the time and frequency domain.

[0017] [Figure 12] 12A and 12B show examples of three downlink and uplink beam management procedures, respectively.

[0018] [Figure 13] 13A, 13B, and 13C show a four-step contention-based random access procedure, a two-step contention-free random access procedure, and an alternative two-step random access procedure, respectively.

[0019] [Figure 14]Figure 14A shows an example of a CORESET configuration for bandwidth portions, and Figure 14B shows an example of CCE to REG mapping for DCI transmission on CORESET and PDCCH processing.

[0020] [Figure 15] FIG. 15 illustrates an embodiment of a wireless device communicating with a base station.

[0021] [Figure 16] 16A, 16B, 16C, and 16D show example structures for uplink and downlink transmissions.

[0022] [Figure 17] Figure 17A illustrates an example application scenario of an EN-DC deployment, according to some embodiments. Figure 17B illustrates an example of uplink operation modes of a UE in Area A and Area B based on the application scenario illustrated in Figure 17A, according to some embodiments.

[0023] [Figure 18] Figure 18A illustrates an example application scenario for UL inter-band CA, according to some embodiments. Figure 18B illustrates an example of uplink operation modes for UEs in Area A and Area B based on the application scenario illustrated in Figure 18A, according to some embodiments.

[0024] [Figure 19] Figure 19A illustrates an example of complementary uplink coverage (SUL) in accordance with some embodiments. Figure 19B illustrates an exemplary application scenario for SUL in accordance with some embodiments. Figure 19C illustrates an example of an uplink operation mode for a UE in Area A and Area B based on the applicable example shown in Figure 19B in accordance with some embodiments.

[0025] [Figure 20]FIG. 20 illustrates an example of a wireless device transmitter antenna, according to some embodiments.

[0026] [Figure 21] Figure 21A shows an example of uplink Tx switching for a UE with 2 Tx, according to some embodiments. Figure 21B shows an example of transmission options for UL Tx switching, according to some embodiments.

[0027] [Figure 22] Figure 22A illustrates an example of an uplink operation mode for a UE with uplink Tx switching in an EN-DC scenario, Figure 22B illustrates an example of an uplink operation mode for a UE with uplink Tx switching in an inter-band CA scenario, and Figure 22C illustrates an example of an uplink operation mode for a UE with uplink Tx switching in a SUL scenario, according to some embodiments.

[0028] [Figure 23] 23A and 23B show examples of UL Tx switching period positions according to some embodiments.

[0029] [Figure 24] FIG. 24 illustrates an example of UL Tx switching for a 2Tx UE, according to some embodiments.

[0030] [Figure 25] FIG. 25 illustrates an example of UL Tx switching for a 2Tx UE across more than two bands, according to some embodiments.

[0031] [Figure 26] FIG. 26 illustrates an example of a UL carrier pair configured for dynamic UL Tx switching, according to some embodiments.

[0032] [Figure 27] FIG. 27 illustrates an example of signaling between a UE and a base station for carrier pair configuration, according to some embodiments.

[0033] [Figure 28] FIG. 28 illustrates an example of a UL carrier pair configured for dynamic UL Tx switching, according to some embodiments.

[0034] [Figure 29] FIG. 29 shows an example of dynamic UL Tx switching across four UL carriers in four different bands, according to some embodiments.

[0035] [Figure 30] FIG. 30 shows an example of dynamic UL Tx switching, according to some embodiments.

[0036] [Figure 31] FIG. 31 shows an example of dynamic UL Tx switching, according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0037] As used herein, "a" and "an" and similar phrases are interpreted as "at least one" and "one or more." Similarly, any term ending in the suffix "(s)" should be interpreted as "at least one" and "one or more." As used herein, the term "may" should be interpreted as "may, for example." In other words, the term "may" indicates that the phrase following the term "may" is one example of multiple preferred possibilities and may or may not be used with one or more of various embodiments. As used herein, the terms "comprises" and "consists of" list one or more components of a described element. The term "comprises" is interchangeable with "includes" and does not exclude unlisted components included in a described element. In contrast, "consists of" provides a complete list of one or more components of a described element. As used herein, the term "based on" should be interpreted as "based at least in part on," rather than, for example, "based only on." As used herein, the term "and / or" refers to any possible combination of the listed elements. For example, "A, B, and / or C" can refer to A, B, C, A and B, A and C, B and C, or A, B, and C.

[0038] If A and B are sets and every element of A is also an element of B, then A is said to be a subset of B. Only non-empty sets and subsets are considered herein. For example, possible subsets of B = {cell1, cell2} are {cell1}, {cell2}, and {cell1, cell2}. The phrase "based on" (or equivalently, "based at least on") indicates that the phrase following the term "based on" is one example of many suitable possibilities that may or may not be used in one or more of various embodiments. The phrase "responsive to" (or equivalently, "at least in response to") indicates that the phrase following the phrase "responsive to" is one example of many suitable possibilities that may or may not be used in one or more of various embodiments. The phrase "in response to" (or equivalently, "at least in response to") indicates that the phrase following the phrase "in response to" is one example of many suitable possibilities that may or may not be used in one or more of various embodiments. The phrase "adopted / used" (or equivalently "adopted / used at least") indicates that the phrase following the phrase "adopted / used" is one example of many suitable possibilities that may or may not be used in one or more of the various embodiments.

[0039] The term configured may relate to the capacity of a device, regardless of whether the device is in an operational or non-operational state. Configuring may refer to a particular setting of a device that affects the operational characteristics of the device, regardless of whether the device is in an operational or non-operational state. In other words, hardware, software, firmware, registers, memory values, etc. may be "configured" within a device, regardless of whether the device is in an operational or non-operational state, to provide the device with particular characteristics. A term such as "control message originating at a device" may mean that the control message has parameters that can be used to configure particular characteristics in the device or to implement particular actions in the device, regardless of whether the device is in an operational or non-operational state.

[0040] In this disclosure, a parameter (or equivalently referred to as a field, or information element: IE) may contain one or more information objects, which in turn may contain one or more other objects. For example, if parameter (IE)N contains parameter (IE)M, which contains parameter (IE)K, which in turn contains parameter (information element) J, then N contains K and N contains J. In an exemplary embodiment, when one or more messages contain multiple parameters, it means that a parameter of the multiple parameters is included in at least one of the one or more messages, but need not be included in each of the one or more messages.

[0041] Many presented features are described as optional through the use of "may" or parentheses. For the sake of brevity and readability, this disclosure does not explicitly describe each and every variation that may be obtained by selecting from a set of optional features. This disclosure should be construed as explicitly disclosing all such variations. For example, a system described as having three optional features may be embodied in seven ways: with only one of the three possible features, any two of the three features, or three of the three features.

[0042] Many of the elements described in the disclosed embodiments may be implemented as modules. Here, a module is defined as an element that performs a defined function and has a defined interface to other elements. The modules described in this disclosure may be implemented in hardware, software in combination with hardware, firmware, wetware (e.g., hardware with biological components), or a combination thereof, which may be behaviorally equivalent. For example, a module may be implemented as a software routine written in a computer language configured to run on a hardware machine (e.g., C, C++, Fortran, Java, Basic, Matlab, etc.) or Simulink, Stateflow, GNU Octave, or LabVIEW MathScript. It may also be possible to implement modules using physical hardware incorporating discrete or programmable analog, digital, and / or quantum hardware. Examples of programmable hardware include computers, microcontrollers, microprocessors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and complex programmable logic devices (CPLDs). Computers, microcontrollers, and microprocessors are programmed using languages ​​such as assembly, C, and C++. FPGAs, ASICs, and CPLDs are often programmed using hardware description languages ​​(HDLs) such as Verilog or Verilog Hardware Description Language (VHDL), which configure the connections between the programmable device's less functional internal hardware modules. The above techniques are often used in combination to achieve a functional modular result.

[0043] 1A illustrates an example of a mobile communication network 100 in which an embodiment of the present disclosure may be implemented. The mobile communication network 100 may be, for example, a public land mobile network (PLMN) launched by a network operator. As shown in FIG. 1A, the mobile communication network 100 includes a core network (CN) 102, a radio access network (RAN) 104, and wireless devices 106.

[0044] The CN 102 may provide the wireless device 106 with an interface to one or more data networks (DNs), such as a public DN (e.g., the Internet), a private DN, and / or an intra-operator DN. As part of its interfacing function, the CN 102 may set up an end-to-end connection between the wireless device 106 and one or more DNs, authenticate the wireless device 106, and provide charging functionality.

[0045] The RAN 104 may connect the CN 102 to the wireless devices 106 via wireless communication over an air interface. As part of the wireless communication, the RAN 104 may provide scheduling, radio resource management, and retransmission protocols. The communication direction over the air interface from the RAN 104 to the wireless devices 106 is known as the downlink, and the communication direction over the air interface from the wireless devices 106 to the RAN 104 is known as the uplink. Downlink transmissions may be separated from uplink transmissions using frequency division duplexing (FDD), time division duplexing (TDD), and / or some combination of the two duplexing techniques.

[0046] The term wireless device may be used throughout this disclosure to refer to and encompass any mobile or fixed (non-portable) device for which wireless communication is required or available. For example, a wireless device may be a phone, a smartphone, a tablet, a computer, a laptop, a sensor, a meter, a wearable device, an Internet of Things (IoT) device, a vehicular roadside unit (RSU), a relay node, an automobile, and / or any combination thereof. The term wireless device encompasses other terms, including user equipment (UE), user terminal (UT), access terminal (AT), mobile station, handset, wireless transmit / receive unit (WTRU), and / or wireless communication device.

[0047] The RAN 104 may include one or more base stations (not shown). The term base station may be used throughout this disclosure to refer to and encompass a Node B (associated with UMTS and / or 3G standards), an evolved Node B (eNB, associated with E-UTRA and / or 4G standards), a remote radio head (RRH), a baseband processing unit coupled to one or more RRHs, a repeater or relay node used to extend the coverage area of ​​a donor node, a next generation evolved Node B (ng-eNB), a generation Node B (gNB, associated with NR and / or 5G standards), an access point (AP, e.g., associated with WiFi or other suitable wireless communication standard), and / or any combination thereof. A base station may include at least one gNB central unit (gNB-CU) and at least one gNB distributed unit (gNB-DU).

[0048] The base stations included in the RAN 104 may include one or more sets of antennas for communicating over the air interface with the wireless devices 106. For example, one or more of the base stations may include three sets of antennas for controlling three cells (or sectors), respectively. The size of a cell may be determined by the range over which a receiver (e.g., a base station receiver) can successfully receive transmissions from a transmitter (e.g., a wireless device transmitter) operating in the cell. Together, the base station cells may provide wireless coverage to the wireless devices 106 over a wide geographic area to support wireless device mobility.

[0049] In addition to three-sector sites, other implementations of base stations are possible. For example, one or more of the base stations of the RAN 104 may be implemented as a sector site having more or less than three sectors. One or more of the base stations of the RAN 104 may be implemented as an access point, as a base-band processing unit coupled to multiple remote radio heads (RRHs), and / or as a repeater or relay node used to extend the coverage area of ​​a donor node. The base-band processing unit coupled to the RRHs may be part of a centralized or cloud RAN architecture, and the base-band processing unit may be centralized or virtualized within a pool of base-band processing units. A repeater node may amplify and rebroadcast wireless signals received from a donor node. A relay node may perform the same / similar functions as a repeater node, but may decode wireless signals received from a donor node and remove noise before amplifying and rebroadcasting the wireless signals.

[0050] The RAN 104 may be deployed as a homogeneous network of macrocell base stations having similar antenna patterns and similar high levels of transmit power. The RAN 104 may be deployed as a heterogeneous network. In a heterogeneous network, small cell base stations may be used to provide small coverage areas, such as coverage areas that overlap with the relatively large coverage areas provided by macrocell base stations. The small coverage areas may be provided in areas of high data traffic (or so-called "hot spots") or areas where macrocell coverage is weak. Examples of small cell base stations include, in order of decreasing coverage area, microcell base stations, picocell base stations, and femtocell or home base stations.

[0051] The Third Generation Partnership Project (3GPP®) was formed in 1998 to provide global standardization of specifications for mobile communication networks similar to the mobile communication network 100 of FIG. 1A. To date, 3GPP® has produced specifications for three generations of mobile networks: a third-generation (3G) network known as Universal Mobile Telecommunications System (UMTS), a fourth-generation (4G) network known as Long Term Evolution (LTE), and a fifth-generation (5G) network known as 5G Systems (5GS). Embodiments of the present disclosure are described with reference to a RAN of a 3GPP® 5G network, referred to as Next Generation RAN (NG-RAN). Embodiments may be applicable to the RAN 104 of FIG. 1A, RANs of earlier 3G and 4G networks, and RANs of other mobile communication networks, such as future networks not yet specified (e.g., a 3GPP® 6G network). NG-RAN implements the 5G radio access technology known as New Radio (NR) and can be provisioned to implement other radio access technologies, including 4G radio access technology or non-3GPP radio access technologies.

[0052] 1B illustrates another exemplary mobile communication network 150 in which embodiments of the present disclosure may be implemented. The mobile communication network 150 may be, for example, a PLMN launched by a network operator. As shown in FIG. 1B, the mobile communication network 150 includes a 5G core network (5G-CN) 152, an NG-RAN 154, and UEs 156A and 156B (collectively, UEs 156). These components may be implemented and operate in the same or similar manner as the corresponding components described with respect to FIG. 1A.

[0053] The 5G-CN 152 provides the UE 156 with an interface to one or more DNs, such as a public DN (e.g., the Internet), a private DN, and / or an intra-operator DN. As part of its interfacing functions, the 5G-CN 152 may set up an end-to-end connection between the UE 156 and one or more DNs, authenticate the UE 156, and provide charging functions. Compared to the CNs of 3GPP® 4G networks, the base of the 5G-CN 152 may be a service-based architecture. This means that the architecture of the nodes that make up the 5G-CN 152 may be defined as network functions that provide services through interfaces to other network functions. The network functions of the 5G-CN 152 may be implemented in several ways: as network elements on dedicated or shared hardware, as software instances running on dedicated or shared hardware, or as virtualized functions instantiated on a platform (e.g., a cloud-based platform).

[0054] As shown in FIG. 1B, the 5G-CN 152 includes an access and mobility management function (AMF) 158A and a user plane function (UPF) 158B, which are shown in FIG. 1B as a single component, AMF / UPF 158, for ease of explanation. The UPF 158B may function as a gateway between the NG-RAN 154 and one or more DNs. The UPF 158B may perform functions such as packet routing and forwarding, packet inspection and user plane policy rule enforcement, traffic usage reporting, uplink classification to support routing of traffic flows to one or more DNs, quality of service (QoS) processing for the user plane (e.g., packet filtering, gating, uplink / downlink rate enforcement, and uplink traffic validation), downlink packet buffering, and downlink data notification triggers. The UPF 158B may function as an anchor point for intra / inter-radio access technology (RAT) mobility, an external protocol (or packet) data unit (PDU) session point interconnected to one or more DNs, and / or a branching point to support multi-homed PDU sessions. The UE 156 may be configured to receive services via a PDU session, which is a logical connection between the UE and the DN.

[0055] The AMF 158A may perform functions such as termination of non-access stratum (NAS) signaling, NAS signaling security, access stratum (AS) security control, inter-CN node signaling for mobility between 3GPP® access networks, idle mode UE reachability (e.g., control and execution of paging retransmissions), registration area management, intra-system and inter-system mobility support, access authentication, access authorization including checking roaming rights, mobility management control (subscription and policy), support for network slicing, and / or session management function (SMF) selection. NAS may refer to functions operating between the CN and the UE, and AS may refer to functions operating between the UE and the RAN.

[0056] 5G-CN 152 may include one or more additional network functions not shown in FIG. 1B for clarity. For example, 5G-CN 152 may include one or more of a Session Management Function (SMF), an NR Repository Function (NRF), a Policy Control Function (PCF), a Network Exposure Function (NEF), a Unified Data Management (UDM), an Application Function (AF), and / or an Authentication Server Function (AUSF).

[0057] The NG-RAN 154 may connect the 5G-CN 152 to the UE 156 via wireless communication over the air interface. The NG-RAN 154 may include one or more gNBs (collectively gNBs 160), illustrated as gNB 160A and gNB 160B, and / or one or more ng-eNBs (collectively ng-eNBs 162), illustrated as ng-eNB 162A and ng-eNB 162B. The gNBs 160 and ng-eNBs 162 may be more generally referred to as base stations. The gNBs 160 and ng-eNBs 162 may include one or more sets of antennas for communicating with the UE 156 over the air interface. For example, one or more of the gNBs 160 and / or one or more of the ng-eNBs 162 may include three sets of antennas for controlling three cells (or sectors), respectively. Together, the gNB160 and ng-eNB162 cells may provide radio coverage to the UE156 over a wide geographic area to support UE mobility.

[0058] As shown in FIG. 1B, the gNB 160 and / or ng-eNB 162 may be connected to the 5G-CN 152 via an NG interface and to other base stations via an Xn interface. The NG and Xn interfaces may be established using direct physical connections and / or indirect connections over an underlying transport network, such as an Internet Protocol (IP) transport network. The gNB 160 and / or ng-eNB 162 may be connected to the UE 156 via a Uu interface. For example, as shown in FIG. 1B, the gNB 160A may be connected to the UE 156A via a Uu interface. The NG, Xn, and Uu interfaces are associated with protocol stacks. The protocol stacks associated with the interfaces may be used by the network elements of FIG. 1B to exchange data and signaling messages and may include two planes: a user plane and a control plane. The user plane may process data of interest to the user. The control plane may process signaling messages of interest to the network elements.

[0059] The gNB 160 and / or ng-eNB 162 may be connected to one or more AMF / UPF functions of the 5G-CN 152, such as the AMF / UPF 158, by one or more NG interfaces. For example, the gNB 160A may be connected to the UPF 158B of the AMF / UPF 158 by an NG-User Plane (NG-U) interface. The NG-U interface may provide for the provisioning of user plane PDUs between the gNB 160A and the UPF 158B (e.g., non-guaranteed delivery). The gNB 160A may connect to the AMF 158A using an NG Control Plane (NG-C) interface. The NG-C interface may provide, for example, NG interface management, UE context management, UE mobility management, transport of NAS messages, paging, PDU session management, and configuration transfer and / or alert message transmission.

[0060] The gNB 160 may provide NR user plane and control plane protocol terminations toward the UE 156 over the Uu interface. For example, the gNB 160A may provide NR user plane and control plane protocol terminations toward the UE 156A over the Uu interface associated with a first protocol stack. The ng-eNB 162 may provide Evolved UMTS Terrestrial Radio Access (E-UTRA) user plane and control plane protocol terminations toward the UE 156 over the Uu interface, where E-UTRA refers to a 3GPP 4G radio access technology. For example, the ng-eNB 162B may provide E-UTRA user plane and control plane protocol terminations toward the UE 156B over the Uu interface associated with a second protocol stack.

[0061] The 5G-CN 152 has been described as being configured to handle NR and 4G radio access. Those skilled in the art will understand that it may be possible for the NR to connect to a 4G core network in a mode known as "non-standalone operation." In non-standalone operation, the 4G core network is used to provide (or at least support) control plane functions (e.g., initial access, mobility, and paging). Although only one AMF / UPF 158 is shown in FIG. 1B, one gNB or ng-eNB may be connected to multiple AMF / UPF nodes to provide redundancy and / or load sharing across multiple AMF / UPF nodes.

[0062] 1B, interfaces between network elements (e.g., Uu, Xn, and NG interfaces) may be associated with protocol stacks that the network elements use to exchange data and signaling messages. The protocol stacks may include two planes: a user plane and a control plane. The user plane may process data of interest to users, and the control plane may process signaling messages of interest to network elements.

[0063] Figures 2A and 2B show example NR user plane and NR control plane protocol stacks, respectively, for the Uu interface between UE 210 and gNB 220. The protocol stacks shown in Figures 2A and 2B may be the same as or similar to those used for the Uu interface between UE 156A and gNB 160A shown in Figure 1B, for example.

[0064] 2A shows an NR user plane protocol stack including five layers implemented in the UE 210 and the gNB 220. At the bottom of the protocol stack, physical layers (PHYs) 211 and 221 may provide transport services to the higher layers of the protocol stack and may correspond to Layer 1 of the Open Systems Interconnection (OSI) model. The next four protocols above the PHYs 211 and 221 include media access control layers (MACs) 212 and 222, radio link control layers (RLCs) 213 and 223, packet data convergence protocol layers (PDCPs) 214 and 224, and service data application protocol layers (SDAPs) 215 and 225. Together, these four protocols may constitute Layer 2, or the data link layer, of the OSI model.

[0065] FIG. 3 illustrates an example of services provided between protocol layers in the NR user plane protocol stack. Starting from the top of FIGS. 2A and 3, the SDAPs 215 and 225 may perform QoS flow processing. The UE 210 may receive services via a PDU session, which may be a logical connection between the UE 210 and the DN. A PDU session may have one or more QoS flows. A UPF (e.g., UPF 158B) in the CN may map IP packets to one or more QoS flows of the PDU session based on QoS requirements (e.g., in terms of delay, data rate, and / or error rate). The SDAPs 215 and 225 may perform mapping / de-mapping between one or more QoS flows and one or more data radio bearers. The mapping / de-mapping between QoS flows and data radio bearers may be determined by the SDAP 225 at the gNB 220. The SDAP 215 at the UE 210 may be informed of the mapping between QoS flows and data radio bearers via reflected mapping or control signaling received from the gNB 220. For reflective mapping, the SDAP 225 at the gNB 220 may mark the downlink packets with a QoS flow indicator (QFI) that may be observed by the SDAP 215 at the UE 210 to determine mapping / de-mapping between QoS flows and data radio bearers.

[0066] The PDCPs 214 and 224 may perform header compression / decompression to reduce the amount of data that needs to be transmitted over the air interface, encryption / decryption to prevent unauthorized decoding of data transmitted over the air interface, and integrity protection (to ensure that control messages originate from the intended source). The PDCPs 214 and 224 may perform retransmission of undelivered packets, in-sequence delivery and reordering of packets, and elimination of duplicate received packets for intra-gNB handover, for example. The PDCPs 214 and 224 may perform packet duplication to improve the likelihood of a packet being received and to eliminate any duplicate packets at the receiver. Packet duplication may be useful for services that require high reliability.

[0067] Although not shown in FIG. 3 , the PDCPs 214 and 224 may perform mapping / demapping between split radio bearers and RLC channels in a dual connectivity scenario. Dual connectivity is a technique that allows a UE to connect to two cells, or more generally, two cell groups: a master cell group (MCG) and a secondary cell group (SCG). A split bearer is when a single radio bearer, such as one of the radio bearers provided by the PDCPs 214 and 224 as a service to the SDAPs 215 and 225, is handled by a cell group in dual connectivity. The PDCPs 214 and 224 may map / demap the split radio bearer between the RLC channels belonging to the cell group.

[0068] The RLCs 213 and 223 may perform segmentation, retransmission via automatic repeat request (ARQ), and elimination of duplicate data units received from the MACs 212 and 222, respectively. The RLCs 213 and 223 may support three transmission modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). Based on the transmission mode in which the RLC is operating, the RLC may perform one or more of the indicated functions. This RLC configuration may be per logical channel, independent of numerology and / or transmission time interval (TTI) duration. As shown in FIG. 3, the RLCs 213 and 223 may provide RLC channels as services to the PDCPs 214 and 224, respectively.

[0069] The MACs 212 and 222 may perform multiplexing / demultiplexing of logical channels and / or mapping between logical channels and transport channels. Multiplexing / demultiplexing may include multiplexing / demultiplexing of data units belonging to one or more logical channels to / from transport blocks (TBs) delivered to / from the PHYs 211 and 221. The MAC 222 may be configured to perform scheduling, scheduling information reporting, and prioritization between UEs through dynamic scheduling. Scheduling may be performed at the gNB 220 (at the MAC 222) for the downlink and uplink. The MACs 212 and 222 may be configured to perform error correction, prioritization between the UE's 210 logical channels through logical channel prioritization, and / or padding through hybrid automatic repeat request (HARQ) (e.g., one HARQ entity per carrier in the case of carrier aggregation (CA)). The MACs 212 and 222 may support one or more numerologies and / or transmission timings. In an embodiment, mapping restrictions on logical channel prioritization may control which numerology and / or transmission timing a logical channel may use. As shown in Figure 3, MACs 212 and 222 may offer logical channels as services to RLCs 213 and 223.

[0070] The PHYs 211 and 221 may perform mapping of transport channels to physical channels and digital and analog signal processing functions to transmit and receive information over the air interface. These digital and analog signal processing functions may include, for example, coding / decoding and modulation / demodulation. The PHYs 211 and 221 may perform multi-antenna mapping. As shown in FIG. 3, the PHYs 211 and 221 may provide one or more transport channels as services to the MACs 212 and 222.

[0071] Figure 4A shows an example downlink data flow through the NR user plane protocol stack. Figure 4A shows the downlink data flow of three IP packets (n, n+1, and m) through the NR user plane protocol stack, generating two TBs at gNB 220. The uplink data flow through the NR user plane protocol stack may be similar to the downlink data flow shown in Figure 4A.

[0072] The downlink data flow in Figure 4A starts when the SDAP 225 receives three IP packets from one or more QoS flows and maps the three packets to radio bearers. In Figure 4A, the SDAP 225 maps IP packets n and n+1 to the first radio bearer 402 and maps IP packet m to the second radio bearer 404. An SDAP header (labeled "H" in Figure 4A) is added to the IP packets. Data units from / to higher protocol layers are referred to as service data units (SDUs) of the lower protocol layers, and data units to / from lower protocol layers are referred to as protocol data units (PDUs) of the higher protocol layers. As shown in Figure 4A, the data units from the SDAP 225 are SDUs of the lower protocol layer PDCP 224 and PDUs of the SDAP 225.

[0073] The remaining protocol layers in FIG. 4A may perform associated functions (e.g., with respect to FIG. 3), add corresponding headers, and forward their respective outputs to the next lower layer. For example, PDCP 224 may perform IP header compression and encryption and forward its output to RLC 223. RLC 223 may optionally perform segmentation (e.g., as shown for IP packet m in FIG. 4A) and forward its output to MAC 222. MAC 222 may multiplex several RLC PDUs and attach MAC subheaders to the RLC PDUs to form transport blocks. In NR, the MAC subheaders may be distributed throughout the MAC PDU, as shown in FIG. 4A. In LTE, the MAC subheader may be located entirely at the beginning of the MAC PDU. The NR MAC PDU structure may reduce processing time and associated delays because the MAC PDU subheaders may be calculated before the complete MAC PDU is assembled.

[0074] 4B shows an example format of a MAC subheader in a MAC PDU. The MAC subheader includes an SDU length field to indicate the length (e.g., in bytes) of the MAC SDU to which the MAC subheader corresponds, a logical channel identifier (LCID) field to identify the logical channel on which the MAC SDU started to assist in the demultiplexing process, a flag (F) to indicate the size of the SDU length field, and a reserved bit (R) field for future use.

[0075] FIG. 4B further illustrates a MAC Control Element (CE) inserted into a MAC PDU by a MAC, such as MAC 223 or MAC 222. For example, FIG. 4B illustrates two MAC CEs inserted into a MAC PDU. A MAC CE may be inserted at the start of a MAC PDU for downlink transmission (as shown in FIG. 4B) and at the end of a MAC PDU for uplink transmission. MAC CEs may be used for in-band control signaling. Examples of MAC CEs include scheduling-related MAC CEs such as buffer status reports and power headroom reports, activation / deactivation MAC CEs such as those for PDCP duplicate detection activation / deactivation, channel state information (CSI) reports, sounding reference signal (SRS) transmissions, and pre-configured components, discontinuous reception (DRX)-related MAC CEs, timing advancement MAC CEs, and random access-related MAC CEs. A MAC CE may be preceded by a MAC subheader of a format similar to that described for a MAC SDU and may be identified with a reserved value in the LCID field indicating the type of control information included in the MAC CE.

[0076] Before describing the NR control plane protocol stack, we first describe logical, transport, and physical channels and the mapping between channel types, one or more of which may be used to perform functions related to the NR control plane protocol stack, as described below.

[0077] Figures 5A and 5B show the mapping between logical channels, transport channels, and physical channels for the downlink and uplink, respectively. Information is passed through channels between the RLC, MAC, and PHY of the NR protocol stack. Logical channels may be used between the RLC and MAC and may be classified as control channels, which carry control and configuration information in the NR control plane, or as traffic channels, which carry data in the NR user plane. Logical channels may be classified as dedicated logical channels dedicated to a specific UE or as common logical channels that can be used by two or more UEs. Logical channels may also be defined by the type of information they carry. The set of logical channels defined by NR includes, for example, - a paging control channel (PCCH) for carrying paging messages used to page UEs whose location is unknown to the network at the cell level; - a Broadcast Control Channel (BCCH) for carrying system information messages in the form of a Master Information Block (MIB) and several System Information Blocks (SIBs), which can be used by UEs to obtain information about how the cell is configured and how to operate within the cell; - a Common Control Channel (CCCH) for carrying control messages along with random access; - a dedicated control channel (DCCH) for carrying control messages to and from a specific UE for configuring the UE; - Dedicated Traffic Channel (DTCH) for carrying user data to and from a specific UE.

[0078] Transport channels are used between the MAC and PHY layers and may be defined by how the information they carry is transmitted over the air interface. The set of transport channels defined by NR includes, for example: - a paging channel (PCH) for carrying paging messages originating from the PCCH; - a Broadcast Channel (BCH) for carrying the MIB from the BCCH; - a Downlink Shared Channel (DL-SCH) for carrying downlink data and signaling messages, including SIBs from the BCCH; - an uplink shared channel (UL-SCH) for carrying uplink data and signaling messages; - A random access channel (RACH) that allows a UE to contact the network without prior scheduling.

[0079] The PHY may use physical channels to pass information between processing levels of the PHY. A physical channel may have an associated set of time-frequency resources for carrying information for one or more transport channels. The PHY may generate control information to support the lower-level operation of the PHY and provide control information to the lower levels of the PHY via physical control channels known as L1 / L2 control channels. The set of physical channels and physical control channels defined by NR may include, for example: - a Physical Broadcast Channel (PBCH) for carrying the MIB from the BCH; - a Physical Downlink Shared Channel (PDSCH) for carrying downlink data and signaling messages from the DL-SCH and paging messages from the PCH; - a Physical Downlink Control Channel (PDCCH) for carrying Downlink Control Information (DCI), which may include downlink scheduling commands, uplink scheduling grants, and uplink power control commands; a Physical Uplink Shared Channel (PUSCH) for carrying uplink data and signaling messages from the UL-SCH and, in some cases, Uplink Control Information (UCI), as described below; - a physical uplink control channel (PUCCH) for carrying UCI, which may include a HARQ acknowledgement, a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and a scheduling request (SR); - A Physical Random Access Channel (PRACH) for random access.

[0080] Similar to the physical control channel, the physical layer generates physical signals to support the low-level operations of the physical layer. As shown in Figures 5A and 5B, the physical layer signals defined by NR include the Primary Synchronization Signal (PSS), the Secondary Synchronization Signal (SSS), the Channel State Information Reference Signal (CSI-RS), the Demodulation Reference Signal (DMRS), the Sounding Reference Signal (SRS), and the Phase Tracking Reference Signal (PT-RS). These physical layer signals are described in more detail below.

[0081] 2B shows an example NR control plane protocol stack. In FIG. 2B, the NR control plane protocol stack may use the same / similar first four protocol layers as the example NR user plane protocol stack. These four protocol layers include PHY 211 and 221, MAC 212 and 222, RLC 213 and 223, and PDCP 214 and 224. Instead of having SDAP 215 and 225 at the top of the stack like the NR user plane protocol stack, the NR control plane stack has radio resource control (RRC) 216 and 226 and NAS protocols 217 and 237 at the top of the NR control plane protocol stack.

[0082] The NAS protocols 217 and 237 may provide control plane functions between the UE 210 and the AMF 230 (e.g., AMF 158A), or more generally, between the UE 210 and the CN. The NAS protocols 217 and 237 may provide control plane functions between the UE 210 and the AMF 230 via signaling messages called NAS messages. There is no direct path between the UE 210 and the AMF 230 over which NAS messages can be transported. NAS messages can be transported using ASs on the Uu and NG interfaces. The NAS protocols 217 and 237 may provide control plane functions such as authentication, security, connection setup, mobility management, and session management.

[0083] The RRCs 216 and 226 may provide a control plane function between the UE 210 and the gNB 220, or more generally, between the UE 210 and the RAN. The RRCs 216 and 226 may provide a control plane function between the UE 210 and the gNB 220 via signaling messages referred to as RRC messages. The RRC messages may be transmitted between the UE 210 and the RAN using signaling radio bearers and the same / similar PDCP, RLC, MAC, and PHY protocol layers. The MAC may multiplex control plane and user plane data within the same transport block (TB). The RRCs 216 and 226 may provide control plane functions such as broadcasting system information related to the AS and NAS, paging initiated by the CN or RAN, establishment, maintenance, and release of an RRC connection between the UE 210 and the RAN, security functions including key management, establishment, configuration, maintenance, and release of signaling and data radio bearers, mobility functions, QoS management functions, UE measurement reporting and reporting control, radio link failure (RLF) detection and recovery, and / or NAS message forwarding. As part of establishing an RRC connection, the RRCs 216 and 226 may establish an RRC context, which may involve setting parameters for communications between the UE 210 and the RAN.

[0084] 6 is an example diagram illustrating RRC state transitions for a UE. The UE may be the same as or similar to the wireless device 106 shown in FIG. 1A, the UE 210 shown in FIG. 2A and FIG. 2B, or any other wireless device described in this disclosure. As shown in FIG. 6, the UE may be in at least one of three RRC states: RRC connected 602 (e.g., RRC_CONNECTED), RRC idle 604 (e.g., RRC_IDLE), and RRC inactive 606 (e.g., RRC_INACTIVE).

[0085] In the RRC connection 602, the UE has an established RRC context and may have at least one RRC connection with a base station. The base station may be similar to one of the base stations included in the RAN 104 shown in FIG. 1A, one of the gNB 160 or ng-eNB 162 shown in FIG. 1B, the gNB 220 shown in FIGS. 2A and 2B, or any other base station described in this disclosure. The base station to which the UE is connected may have the UE's RRC context. The RRC context, referred to as the UE context, may include parameters for communication between the UE and the base station. These parameters may include, for example, one or more AS contexts, one or more radio link configuration parameters, bearer configuration information (e.g., associated with data radio bearers, signaling radio bearers, logical channels, QoS flows, and / or PDU sessions), security information, and / or PHY, MAC, RLC, PDCP, and / or SDAP layer configuration information. In the RRC connection 602, the UE's mobility may be managed by the RAN (e.g., the RAN 104 or the NG-RAN 154). The UE may measure signal levels (e.g., reference signal levels) from the serving cell and neighboring cells and report these measurements to the base station currently serving the UE. The UE's serving base station may request a handover to a cell of one of the neighboring base stations based on the reported measurements. The RRC state may transition from RRC Connected 602 to RRC Idle 604 via a Connection Release procedure 608 or to RRC Inactive 606 via a Connection Deactivation procedure 610.

[0086] In RRC Idle 604, no RRC context may be established for the UE. In RRC Idle 604, the UE may not have an RRC connection with a base station. While in RRC Idle 604, the UE may be asleep most of the time (e.g., to conserve battery power). The UE may wake up periodically (e.g., once per discontinuous reception cycle) to monitor for paging messages from the RAN. UE mobility may be managed by the UE through a procedure known as cell reselection. The RRC state may transition from RRC Idle 604 to RRC Connected 602 via a connection establishment procedure 612, which may involve a random access procedure as discussed in more detail below.

[0087] In RRC Inactive 606, the previously established RRC context is maintained in the UE and the base station. This reduces signaling overhead and allows for a fast transition to RRC Connected 602 compared to transitioning from RRC Idle 604 to RRC Connected 602. In RRC Inactive 606, the UE is in a sleep state and UE mobility may be managed by the UE through cell reselection. The RRC state may transition from RRC Inactive 606 to RRC Connected 602 by a Connection Resume procedure 614 or to RRC Idle 604 via a Connection Release procedure 616 that is the same as or similar to the Connection Release procedure 608.

[0088] The RRC state may be associated with a mobility management mechanism. In RRC Idle 604 and RRC Inactive 606, mobility is managed by the UE through cell reselection. The purpose of mobility management in RRC Idle 604 and RRC Inactive 606 is to allow the network to notify the UE of events via paging messages without broadcasting the paging messages throughout the entire mobile communication network. The mobility management mechanism used in RRC Idle 604 and RRC Inactive 606 may enable the network to track the UE on a cell group level so that paging messages may be broadcast on cells of the cell group in which the UE currently resides instead of the entire mobile communication network. The mobility management mechanisms in RRC Idle 604 and RRC Inactive 606 track UEs on a cell group level. They may do so using different levels of granularity of grouping. For example, there may be three levels of granularity of cell grouping: individual cells, cells within a RAN area identified by a RAN Area Identifier (RAI), and cells within a group of RAN areas, referred to as a tracking area and identified by a Tracking Area Identifier (TAI).

[0089] The tracking area may be used to track the UE at the CN level. The CN (e.g., CN 102 or 5G-CN 152) may provide the UE with a list of TAIs associated with UE registration areas. If the UE moves, through cell reselection, to a cell associated with a TAI that is not included in the list of TAIs associated with the UE registration area, the UE may perform a registration update with the CN to enable the CN to update the UE's location and provide the UE with a new UE registration area.

[0090] The RAN area may be used to track the UE at the RAN level. For a UE in the RRC inactive 606 state, a RAN notification area may be assigned to the UE. The RAN notification area may include one or more cell identities, a list of RAIs, or a list of TAIs. In an embodiment, a base station may belong to one or more RAN notification areas. In an embodiment, a cell may belong to one or more RAN notification areas. If the UE moves, through cell reselection, to a cell that is not included in the RAN notification area assigned to the UE, the UE may perform a notification area update with the RAN to update the RAN notification area of ​​the UE.

[0091] A base station that stores the RRC context for a UE, or the last serving base station for the UE, may be referred to as an anchor base station. The anchor base station may maintain the RRC context for the UE at least for a period of time that the UE remains in the RAN notification area of ​​the anchor base station and / or for a period of time that the UE remains in RRC inactive 606.

[0092] A gNB, such as gNB 160 in FIG. 1B, may be divided into two parts: a central unit (gNB-CU) and one or more distributed units (gNB-DUs). The gNB-CU may be coupled to one or more gNB-DUs using an F1 interface. The gNB-CU may include RRC, PDCP, and SDAP. The gNB-DU may include RLC, MAC, and PHY.

[0093] In NR, physical signals and physical channels (discussed with reference to Figures 5A and 5B) may be mapped onto orthogonal frequency division multiplexing (OFDM) symbols. OFDM is a multicarrier communication scheme that transmits data on F orthogonal subcarriers (or tones). Before transmission, the data may be mapped to a series of complex symbols (e.g., M-quadrature amplitude modulation (M-QAM) or M-phase shift keying (M-PSK) symbols), referred to as source symbols, which are divided into F parallel symbol streams. The F parallel symbol streams may be treated as if they were in the frequency domain and used as input to an inverse fast Fourier transform (IFFT) block, which converts them to the time domain. The IFFT block may take F source symbols, one from each of the F parallel symbol streams at a time, and use each source symbol to modulate the amplitude and phase of one of the F sinusoidal basis functions corresponding to the F orthogonal subcarriers. The output of the IFFT block may be F time-domain samples representing a sum of the F orthogonal subcarriers. The F time-domain samples may form a single OFDM symbol. After some processing (e.g., adding a cyclic prefix) and upconversion, the OFDM symbols provided by the IFFT block can be transmitted over the air interface at a carrier frequency. The F parallel symbol streams can be mixed using an FFT block before being processed by the IFFT block. This processing produces discrete Fourier transform (DFT) precoded OFDM symbols, which can be used by UEs in the uplink to reduce the peak-to-average power ratio (PAPR). Inverse processing can be performed on the OFDM symbols at the receiver using an FFT block to recover the data mapped to the source symbols.

[0094] FIG. 7 shows an example configuration of an NR frame in which OFDM symbols are grouped. NR frames may be identified by a system frame number (SFN). The SFN may repeat at a period of 1024 frames. As shown, one NR frame may be 10 milliseconds (ms) in duration and may include 10 subframes, each 1 ms in duration. The subframes may be divided into slots, each including, for example, 14 OFDM symbols per slot.

[0095] The duration of a slot may depend on the numerology used for the OFDM symbol of the slot. NR supports flexible numerology to accommodate different cell deployments (e.g., cells with carrier frequencies less than 1 GHz up to cells with carrier frequencies in the mm-wave range). Numerology may be defined in terms of subcarrier spacing and cyclic prefix duration. For numerology in NR, subcarrier spacing may be scaled up by a power of two from the baseline subcarrier spacing of 15 kHz, and cyclic prefix duration may be scaled down by a power of two from the baseline cyclic prefix duration of 4.7 μs. For example, NR defines numerologies with the following subcarrier spacing / cyclic prefix duration combinations: 15 kHz / 4.7 μs, 30 kHz / 2.3 μs, 60 kHz / 1.2 μs, 120 kHz / 0.59 μs, and 240 kHz / 0.29 μs.

[0096] A slot may have a fixed number of OFDM symbols (e.g., 14 OFDM symbols). Numerologies with higher subcarrier spacing have shorter slot durations and correspondingly more slots per subframe. Figure 7 illustrates this numerology-dependent slot duration and slot-per-subframe transmission structure (for ease of illustration, a numerology with 240 kHz subcarrier spacing is not shown in Figure 7). While a subframe in NR may be used as a numerology-independent time reference, a slot may be used as the unit by which uplink and downlink transmissions are scheduled. To support low latency, scheduling in NR is decoupled from the slot duration and can start on any OFDM symbol and continue for as many symbols as necessary for transmission. These partial slot transmissions may be referred to as minislot or subslot transmissions.

[0097] Figure 8 shows an example configuration of a slot in the time and frequency domain of an NR carrier. A slot includes resource elements (REs) and resource blocks (RBs). An RE is the smallest physical resource in NR. An RE spans one OFDM symbol in the time domain by one subcarrier in the frequency domain, as shown in Figure 8. An RB spans 12 consecutive REs in the frequency domain, as shown in Figure 8. An NR carrier may be limited to a width of 275 RBs or 275 x 12 = 3300 subcarriers. If used, these restrictions may limit an NR carrier to 50, 100, 200, and 400 MHz for subcarrier spacings of 15, 30, 60, and 120 kHz, respectively, and the 400 MHz bandwidth may be set based on the 400 MHz per carrier bandwidth limit.

[0098] Figure 8 shows a single numerology used across the entire bandwidth of an NR carrier. In other example configurations, multiple numerologies may be supported on the same carrier.

[0099] NR may support a wide range of carrier bandwidths (e.g., up to 400 MHz with 120 kHz subcarrier spacing). Not all UEs may be able to receive the entire carrier bandwidth (e.g., due to hardware limitations). Also, receiving the entire carrier bandwidth may be prohibitive from a UE power consumption perspective. In embodiments, to reduce power consumption and / or for other purposes, the UE may adapt the size of its reception bandwidth based on the amount of traffic the UE is scheduled to receive. This is referred to as bandwidth adaptation.

[0100] NR defines a bandwidth portion (BWP) to support UEs that cannot receive the entire carrier bandwidth and supports bandwidth adaptation. In one embodiment, a BWP may be defined by a subset of contiguous RBs on a carrier. A UE may be configured (e.g., via the RRC layer) with one or more downlink BWPs and one or more uplink BWPs per serving cell (e.g., up to four downlink BWPs and up to four uplink BWPs per serving cell). At a given time, one or more of the BWPs configured for a serving cell may be active. These one or more BWPs may be referred to as the active BWP of the serving cell. When a serving cell is configured with a secondary uplink carrier, the serving cell may have one or more first active BWPs on the uplink carrier and one or more second active BWPs on the secondary uplink carrier.

[0101] For unpaired spectrum, a downlink BWP from a set of configured downlink BWPs may be linked with an uplink BWP from a set of configured uplink BWPs if the downlink BWP index of the downlink BWP and the uplink BWP index of the uplink BWP are the same. For unpaired spectrum, the UE may expect the center frequency of the downlink BWP to be the same as the center frequency of the uplink BWP.

[0102] For a downlink BWP within a set of configured downlink BWPs on a primary cell (PCell), the base station may configure the UE with one or more control resource sets (CORESETs) for at least one search space. A search space is a set of locations in the time and frequency domain where the UE can find control information. The search space may be a UE-specific search space or a common search space (potentially usable by multiple UEs). For example, the base station may configure the UE with a common search space on the PCell or on a primary secondary cell (PSCell) for an active downlink BWP.

[0103] For an uplink BWP within a set of configured uplink BWPs, the BS may configure the UE with one or more resource sets for one or more PUCCH transmissions. The UE may receive downlink receptions (e.g., PDCCH or PDSCH) within the downlink BWP according to the configured numerology (e.g., subcarrier spacing and cyclic prefix duration) for the downlink BWP. The UE may transmit uplink transmissions (e.g., PUCCH or PUSCH) within the uplink BWP according to the configured numerology (e.g., subcarrier spacing and cyclic prefix length for the uplink BWP).

[0104] One or more BWP indicator fields may be provided in the downlink control information (DCI). The value of the BWP indicator field may indicate which BWPs of a set of configured BWPs are active downlink BWPs for one or more downlink receptions. The value of the one or more BWP indicator fields may indicate active uplink BWPs for one or more uplink transmissions.

[0105] The base station may semi-statically configure the UE with a default downlink BWP within a set of configured downlink BWPs associated with the PCell. If the base station does not provide a default downlink BWP for the UE, the default downlink BWP may be the initial active downlink BWP. The UE may determine which BWP is the initial active downlink BWP based on the CORESET configuration obtained using the PBCH.

[0106] The base station may configure the UE with a BWP inactivity timer value for the PCell. The UE may start or restart the BWP inactivity timer at any appropriate time. For example, the UE may start or restart the BWP inactivity timer (a) when the UE detects a DCI indicating an active downlink BWP other than the default downlink BWP for paired spectrum operation, or (b) when the UE detects a DCI indicating an active downlink BWP or an active uplink BWP other than the default downlink BWP or uplink BWP for unpaired spectrum operation. If the UE does not detect a DCI for a certain period of time (e.g., 1 ms or 0.5 ms), the UE may start the BWP inactivity timer towards expiration (e.g., increasing it from zero to the BWP inactivity timer value or decreasing it from the BWP inactivity timer value to zero). When the BWP inactivity timer expires, the UE may switch from the active downlink BWP to the default downlink BWP.

[0107] In an embodiment, a base station may semi-statically configure a UE with one or more BWPs, and the UE may switch the active BWP from a first BWP to a second BWP in response to receiving a DCI indicating the second BWP as the active BWP and / or in response to expiration of a BWP inactivity timer (e.g., if the second BWP is a default BWP).

[0108] Downlink and uplink BWP switching (BWP switching refers to switching from a currently active BWP to a currently inactive BWP) can occur independently in paired spectrum. In unpaired spectrum, downlink and uplink BWP switching can be performed simultaneously. Switching between configured BWPs can occur based on RRC signaling, DCI, expiration of the BWP inactivity timer, and / or initiation of random access.

[0109] FIG. 9 shows an example of bandwidth adaptation using three configured BWPs for an NR carrier. A UE configured with three BWPs may switch from one BWP to another at a switch point. In the example shown in FIG. 9, the BWPs include BWP 902 with a 40 MHz bandwidth and 15 kHz subcarrier spacing, BWP 904 with a 10 MHz bandwidth and 15 kHz subcarrier spacing, and BWP 906 with a 20 MHz bandwidth and 60 kHz subcarrier spacing. BWP 902 may be the initial active BWP, and BWP 904 may be the default BWP. A UE may switch between BWPs at a switch point. In the example of FIG. 9, the UE may switch from BWP 902 to BWP 904 at switch point 908. Switching at switch point 908 may occur for any suitable reason, such as in response to expiration of a BWP inactivity timer (indicating switching to the default BWP) and / or in response to receiving a DCI indicating BWP 904 as the active BWP. The UE may switch from the active BWP 904 to BWP 906 at switch point 910 in response to receiving a DCI indicating BWP 906 as the active BWP. The UE may switch from the active BWP 906 to BWP 904 at switch point 912 in response to expiration of a BWP inactivity timer and / or in response to receiving a DCI indicating BWP 904 as the active BWP. The UE may switch from the active BWP 904 to BWP 902 at switch point 914 in response to receiving a DCI indicating BWP 902 as the active BWP.

[0110] If the UE is configured for a secondary cell with a default downlink BWP in the set of configured downlink BWPs and timer values, the UE procedure for switching the BWP on the secondary cell may be the same / similar to that on the primary cell. For example, the UE may use timer values ​​and default downlink BWPs for the secondary cell in the same / similar manner that the UE uses these values ​​for the primary cell.

[0111] To provide a higher data rate, two or more carriers can be aggregated and transmitted simultaneously to the same UE using carrier aggregation (CA). The aggregated carriers in CA can be referred to as component carriers (CCs). When CA is used, there are multiple serving cells for the UE and one for the CC. A CC can have three configurations in the frequency domain.

[0112] 10A shows three CA configurations with two CCs. In the intra-band contiguous configuration 1002, two CCs are aggregated in the same frequency band (frequency band A) and are located immediately adjacent to each other within the frequency band. In the intra-band non-contiguous configuration 1004, two CCs are aggregated in the same frequency band (frequency band A) and are separated by a gap. In the intra-band configuration 1006, two CCs are located in frequency bands (frequency band A and frequency band B).

[0113] In an embodiment, up to 32 CCs may be aggregated. The aggregated CCs may have the same or different bandwidths, subcarrier spacing, and / or duplexing schemes (TDD or FDD). A serving cell of a UE using CA may have a downlink CC. In the case of FDD, one or more uplink CCs may optionally be configured for the serving cell. The ability to aggregate more downlink carriers than uplink carriers may be useful, for example, when a UE has more data traffic on the downlink than on the uplink.

[0114] When CA is used, one of the aggregation cells for a UE may be referred to as a primary cell (PCell). The PCell may be a serving cell to which the UE initially connects during RRC connection establishment, re-establishment, and / or handover. The PCell may provide the UE with NAS mobility information and security inputs. A UE may have different PCells. In the downlink, a carrier corresponding to a PCell may be referred to as a downlink primary CC (DL PCC). In the uplink, a carrier corresponding to a PCell may be referred to as an uplink primary CC (UL PCC). Other aggregation cells for a UE may be referred to as secondary cells (SCells). In an embodiment, an SCell may be configured after a PCell is configured for the UE. For example, the SCell may be configured via an RRC connection reconfiguration procedure. In the downlink, a carrier corresponding to a SCell may be referred to as a downlink secondary CC (DL SCC). In the uplink, a carrier corresponding to a SCell may be referred to as an uplink secondary CC (UL SCC).

[0115] A configured SCell for a UE may be activated and deactivated based on, for example, traffic and channel conditions. Deactivating an SCell may mean that PDCCH and PDSCH reception on the SCell is stopped and PUSCH, SRS, and CQI transmission on the SCell is stopped. A configured SCell may be activated and deactivated using a MAC CE with respect to FIG. 4B. For example, the MAC CE may use a bitmap (e.g., one bit per SCell) to indicate which SCells (e.g., among a subset of configured SCells) for a UE are activated or deactivated. A configured SCell may be deactivated in response to expiration of an SCell deactivation timer (e.g., one SCell deactivation timer per SCell).

[0116] Downlink control information, such as scheduling assignments and scheduling grants for a cell, may be transmitted on the cell corresponding to the assignment and grant, known as self-scheduling. DCI for a cell may be transmitted on another cell, known as cross-carrier scheduling. Uplink control information for aggregation cells (e.g., HARQ acknowledgments and channel state feedback such as CQI, PMI, and / or RI) may be transmitted on the PUCCH of the PCell. A large number of aggregated downlink CCs may overload the PUCCH of the PCell. A cell may be divided into multiple PUCCH groups.

[0117] 10B shows an example of how aggregation cells may be configured into one or more PUCCH groups. PUCCH group 1010 and PUCCH group 1050 may each include one or more downlink CCs. In the example of FIG. 10B, PUCCH group 1010 includes three downlink CCs: PCell 1011, SCell 1012, and SCell 1013. PUCCH group 1050 includes three downlink CCs: PCell 1051, SCell 1052, and SCell 1053 in this example. One or more uplink CCs may be configured as PCell 1021, SCell 1022, and SCell 1023. One or more other uplink CCs may be configured as Primary Scell ​​(PSCell) 1061, SCell 1062, and SCell 1063. Uplink control information (UCI) associated with downlink CCs of PUCCH group 1010, denoted as UCI 1031, UCI 1032, and UCI 1033, may be transmitted on the uplink of PCell 1021. Uplink control information (UCI) associated with downlink CCs of PUCCH group 1050, denoted as UCI 1071, UCI 1072, and UCI 1073, may be transmitted on the uplink of PSCell 1061. In an embodiment, if the aggregation cell depicted in FIG. 10B were not divided into PUCCH group 1010 and PUCCH group 1050, a single uplink PCell and PCell for transmitting UCI associated with downlink CCs may be overloaded. By dividing the transmission of UCIs between PCell 1021 and PSCell 1061, overloading may be prevented.

[0118] A cell including a downlink carrier and, optionally, an uplink carrier may be assigned a physical cell ID and a cell index. The physical cell ID or cell index may identify the downlink carrier and / or the uplink carrier of a cell, for example, depending on the context in which the physical cell ID is used. The physical cell ID may be determined using a synchronization signal transmitted on a downlink component carrier. The cell index may be determined using an RRC message. In this disclosure, the physical cell ID may be referred to as a carrier ID, and the cell index may be referred to as a carrier index. For example, when this disclosure refers to a first physical cell ID for a first downlink carrier, this disclosure may mean that the first physical cell ID is for a cell including the first downlink carrier. The same / similar concept may apply, for example, to carrier activation. When this disclosure indicates that a first carrier is activated, this specification may mean that the cell including the first carrier is activated.

[0119] In CA, the multi-carrier nature of the PHY may be exposed to the MAC. In an embodiment, a HARQ entity may operate on the serving cell. Transport blocks may be generated per assignment / grant per serving cell. Transport blocks and potential HARQ retransmissions of transport blocks may be mapped to the serving cell.

[0120] In the downlink, a base station may transmit (e.g., unicast, multicast, and / or broadcast) one or more reference signals (RS) (e.g., PSS, SSS, CSI-RS, DMRS, and / or PT-RS as shown in FIG. 5A) to the UE. In the uplink, the UE may transmit one or more RSs to the base station (e.g., DMRS, PT-RS, and / or SRS as shown in FIG. 5B). The PSS and SSS may be transmitted by the base station and used by the UE to synchronize the UE to the base station. The PSS and SSS may be provided within a synchronization signal (SS) / physical broadcast channel (PBCH) block that includes the PSS, SSS, and PBCH. The base station may periodically transmit bursts of the SS / PBCH block.

[0121] FIG. 11A illustrates an example of the structure and location of SS / PBCH blocks. A burst of SS / PBCH blocks may include one or more SS / PBCH blocks (e.g., four SS / PBCH blocks as shown in FIG. 11A). Bursts may be transmitted periodically (e.g., every two frames or every 20 milliseconds). Bursts may be limited to half-frames (e.g., the first half-frame having a duration of 5 milliseconds). It will be understood that FIG. 11A is an example, and these parameters (number of SS / PBCH blocks per burst, burst periodicity, and burst position within a frame) may be configured based on, for example, the carrier frequency of the cell in which the SS / PBCH blocks are transmitted, the cell's numerology or subcarrier spacing, configuration by the network (e.g., using RRC signaling), or any other suitable factor. In this example, the UE may assume a subcarrier spacing for the SS / PBCH blocks based on the monitored carrier frequency, unless the wireless network configures the UE to assume a different subcarrier spacing.

[0122] An SS / PBCH block may span one or more OFDM symbols in the time domain (e.g., four OFDM symbols as shown in the example of FIG. 11A) and one or more subcarriers in the frequency domain (e.g., 240 consecutive subcarriers). The PSS, SSS, and PBCH may have a common center frequency. The PSS may be transmitted first and may span, for example, one OFDM symbol and 127 subcarriers. The SSS may be transmitted after the PSS (e.g., the last two symbols) and may span one OFDM symbol and 127 subcarriers. The PBCH may be transmitted after the PSS (e.g., over the next three OFDM symbols) and may span 240 subcarriers.

[0123] The location of the SS / PBCH block in the time and frequency domain may be unknown to the UE (e.g., when the UE is searching for a cell). To find and select a cell, the UE may monitor the carrier for a PSS. For example, the UE may monitor a frequency location within the carrier. If the PSS is not found after a certain duration (e.g., 20 milliseconds), the UE may search for a PSS at a different frequency location within the carrier as indicated by the synchronization raster. If the PSS is found at a location in the time and frequency domain, the UE may determine the location of the SSS and PBCH, respectively, based on the known structure of the SS / PBCH block. The SS / PBCH block may be a cell-defined SS block (CD-SSB). In an embodiment, a primary cell may be associated with the CD-SSB. The CD-SSB may be located on the synchronization raster. In an embodiment, cell selection / search and / or reselection may be based on the CD-SSB.

[0124] The SS / PBCH block may be used by the UE to determine one or more parameters of the cell. For example, the UE may determine a physical cell identifier (PCI) of the cell based on the PSS and SSS sequences, respectively. The UE may determine the location of a frame boundary of the cell based on the location of the SS / PBCH block. For example, the SS / PBCH block may indicate that it was transmitted according to a transmission pattern, in which the SS / PBCH block is a known distance from the frame boundary.

[0125] The PBCH may use QPSK modulation and may use forward error correction (FEC). The FEC may use polar coding. One or more symbols spanned by the PBCH may carry one or more DMRSs for demodulation of the PBCH. The PBCH may include an indication of the cell's current system frame number (SFN) and / or SS / PBCH block timing index. These parameters may facilitate time synchronization of the UE to the base station. The PBCH may include a master information block (MIB) used to provide one or more parameters to the UE. The MIB is used to identify the remaining minimum system information (RMSI) with which the UE is associated with the cell. The RMSI may include system information block type 1 (SIB1). SIB1 may include information necessary for the UE to access the cell. The UE may use one or more parameters in the MIB to monitor the PDCCH, which may be used to schedule the PDSCH. The PDSCH may include SIB1. SIB1 may be decoded using the parameters provided in the MIB. The PBCH may indicate the absence of SIB1. Based on the PBCH indicating the absence of SIB1, a frequency may be pointed to the UE, and the UE may search for an SS / PBCH block on the frequency to which the UE is pointed.

[0126] The UE may assume that one or more SS / PBCH blocks transmitted with the same SS / PBCH block index are quasi-co-located (QCL'd) (e.g., have the same / similar Doppler spread, Doppler shift, average gain, average delay, and / or spatial Rx parameters). The UE may not assume that the QCL's for SS / PBCH block transmissions have different SS / PBCH block indices.

[0127] SS / PBCH blocks (e.g., blocks within a half frame) may be transmitted in spatial directions (e.g., using different beams across the coverage area of ​​a cell). In an embodiment, a first SS / PBCH block may be transmitted in a first spatial direction using a first beam, and a second SS / PBCH block may be transmitted in a second spatial direction using a second beam.

[0128] In an embodiment, within the frequency span of a carrier, a base station may transmit multiple SS / PBCH blocks. In an embodiment, a first PCI of a first SS / PBCH block of the multiple SS / PBCH blocks may be different from a second PCI of a second SS / PBCH block of the multiple SS / PBCH blocks. The PCIs of SS / PBCH blocks transmitted at different frequency locations may be different or the same.

[0129] The CSI-RS may be transmitted by a base station and used by a UE to obtain channel state information (CSI). The base station may configure the UE with one or more CSI-RS for channel estimation or any other suitable purpose. The base station may configure the UE with one or more of the same / similar CSI-RS. The UE may measure one or more CSI-RS. The UE may estimate downlink channel conditions and / or generate a CSI report based on measurements of one or more downlink CSI-RS. The UE may provide the CSI report to the base station. The base station may perform link adaptation using feedback provided by the UE (e.g., estimated downlink channel conditions).

[0130] A base station can semi-statically configure a UE with one or more CSI-RS resource sets. The CSI-RS resources can be associated with a location and periodicity in the time and frequency domains. The base station can selectively activate and / or deactivate CSI-RS resources. The base station can indicate to the UE that CSI-RS resources in a CSI-RS resource set are activated and / or deactivated.

[0131] A base station may configure a UE to report CSI measurements. The base station may configure the UE to provide CSI reports periodically, aperiodically, or semi-persistently. For periodic CSI reporting, the UE may be configured with the timing and / or periodicity of the CSI reports. For aperiodic CSI reporting, the base station may request a CSI report. For example, the base station may instruct the UE to measure configured CSI-RS resources and provide a CSI report regarding the measurements. For semi-persistent CSI reporting, the base station may configure the UE to periodically send periodic reports and selectively activate or deactivate them. The base station may configure the UE with a CSI-RS resource set and CSI report using RRC signaling.

[0132] The CSI-RS configuration may include, for example, one or more parameters indicating up to 32 antenna ports. The UE may be configured to use the same OFDM symbol for the downlink CSI-RS and control resource set (CORESET) when the downlink CSI-RS and CORESET are spatially QCL'd and resource elements associated with the downlink CSI-RS are outside the physical resource block (PRB) configured for CORESET. The UE may be configured to use the same OFDM symbol for the downlink CSI-RS and SS / PBCH block when the downlink CSI-RS and SS / PBCH block are spatially QCL'd and resource elements associated with the downlink CSI-RS are outside the PRB configured for the SS / PBCH block.

[0133] Downlink DMRS may be transmitted by a base station and used by a UE for channel estimation. For example, downlink DMRS may be used for coherent demodulation of one or more downlink physical channels (e.g., PDSCH). An NR network may support one or more variable and / or configurable DMRS patterns for data demodulation. At least one downlink DMRS configuration may support a frontloaded DMRS pattern. The frontloaded DMRS may be mapped to one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). The base station may semi-statically configure the UE with the number (e.g., maximum number) of frontloaded DMRS symbols for the PDSCH. A DMRS configuration may support one or more DMRS ports. For example, in the case of single-user MIMO, a DMRS configuration may support up to eight orthogonal downlink DMRS ports per UE. In the case of multi-user MIMO, a DMRS configuration may support up to four orthogonal downlink DMRS ports per UE. The wireless network can support a common downlink and uplink DMRS structure (e.g., at least for CP-OFDM). The DMRS position, DMRS pattern, and / or scrambling sequence can be the same or different. The base station can transmit the downlink DMRS and corresponding PDSCH using the same precoding matrix. The UE can use one or more downlink DMRSs for coherent demodulation / channel estimation of the PDSCH.

[0134] In an embodiment, a transmitter (e.g., a base station) may use a precoder matrix for a portion of a transmission bandwidth. For example, the transmitter may use a first precoder matrix for a first bandwidth and a second precoder matrix for a second bandwidth. The first precoder matrix and the second precoder matrix may differ based on the first bandwidth being different from the second bandwidth. The UE may assume that the same precoding matrix is ​​used across a set of PRBs. The set of PRBs may be denoted as a precoding resource block group (PRG).

[0135] The PDSCH may include one or more layers. The UE may assume that at least one symbol with a DMRS is present on one or more layers of the PDSCH. Higher layers may configure up to three DMRSs for the PDSCH.

[0136] The downlink PT-RS may be transmitted by the base station and used by the UE for phase noise compensation. Whether the downlink PT-RS is present depends on the RRC configuration. The presence and / or pattern of the downlink PT-RS may be configured on a UE-specific basis using a combination of RRC signaling and / or an association with one or more parameters used for other purposes (e.g., modulation and coding scheme (MCS)) that may be indicated by DCI. When configured, the dynamic presence of the downlink PT-RS may be associated with one or more DCI parameters, including at least the MCS. The NR network may support multiple PT-RS densities defined in the time and / or frequency domain. The frequency domain density, if present, may be associated with at least one configuration of the scheduled bandwidth. The UE may assume the same precoding for the DMRS and PT-RS ports. The number of PT-RS ports may be less than the number of DMRS ports within the scheduled resource. The downlink PT-RS may be limited to the UE's scheduled time / frequency duration. The downlink PT-RS may be transmitted over symbols to facilitate phase tracking at the receiver.

[0137] The UE may transmit an uplink DMRS to a base station for channel estimation. For example, the base station may use the uplink DMRS for coherent demodulation of one or more uplink physical channels. For example, the UE may transmit the uplink DMRS on a PUSCH and / or a PUCCH. The uplink DM-RS may span a frequency range similar to the frequency range associated with the corresponding physical channel. The base station may configure the UE with one or more uplink DMRS configurations. At least one DMRS configuration may support a frontloaded DMRS pattern. The frontloaded DMRS may be mapped to one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). One or more uplink DMRS may be configured to transmit on one or more symbols of the PUSCH and / or a PUCCH. The base station may semi-statically configure the UE with the number (e.g., maximum number) of frontloaded DMRS symbols for the PUSCH and / or a PUCCH that the UE may use to schedule single-symbol DMRS and / or dual-symbol DMRS. An NR network may support a common DMRS structure for the downlink and uplink (e.g., for cyclic prefix orthogonal frequency division multiplexing (CP-OFDM)), where the DMRS position, DMRS pattern, and / or DMRS scrambling sequence may be the same or different.

[0138] The PUSCH may include one or more layers, and the UE may transmit at least one symbol having a DMRS present on one or more layers of the PUSCH. In an embodiment, higher layers may configure up to three DMRSs for the PUSCH.

[0139] The uplink PT-RS (which may be used by the base station for phase tracking and / or phase noise compensation) may be present or absent depending on the UE's RRC configuration. The presence and / or pattern of the uplink PT-RS may be configured on a UE-specific basis by a combination of one or more parameters used for other purposes (e.g., modulation and coding scheme (MCS)), which may be indicated by RRC signaling and / or DCI. When configured, the dynamic presence of the uplink PT-RS may be associated with one or more DCI parameters, including at least the MCS. The wireless network may support multiple uplink PT-RS densities defined in the time / frequency domain. The frequency domain density, if present, may be associated with at least one configuration of the scheduled bandwidth. The UE may assume the same precoding for the DMRS and PT-RS ports. The number of PT-RS ports may be less than the number of DMRS ports within the scheduled resources. For example, the uplink PT-RS may be limited to the UE's scheduled time / frequency duration.

[0140] The SRS may be transmitted by the UE to the base station for channel condition estimation to support uplink channel-dependent scheduling and / or link adaptation. The SRS transmitted by the UE may enable the base station to estimate uplink channel conditions at one or more frequencies. The base station scheduler can use the estimated uplink channel conditions to allocate one or more resource blocks for uplink PUSCH transmission from the UE. The base station may semi-statically configure the UE with one or more SRS resource sets. For an SRS resource set, the base station may configure the UE with one or more SRS resources. SRS resource set applicability may be configured by higher layer (e.g., RRC) parameters. For example, when higher layer parameters indicate beam management, SRS resources in one or more SRS resource sets (e.g., having the same / similar time-domain behavior, periodic, aperiodic, and / or the like) may be transmitted instantaneously (e.g., simultaneously). The UE may transmit one or more SRS resources in an SRS resource set. An NR network may support aperiodic, periodic, and / or semi-persistent SRS transmission. A UE may transmit SRS resources based on one or more trigger types, which may include higher layer signaling (e.g., RRC) and / or one or more DCI formats. In an embodiment, at least one DCI format may be used by the UE to select at least one of one or more configured SRS resource sets. SRS trigger type 0 may refer to an SRS triggered based on higher layer signaling. SRS trigger type 1 may refer to an SRS triggered based on one or more DCI formats. In an embodiment, if a PUSCH and an SRS are transmitted in the same slot, the UE may be configured to transmit the SRS after the transmission of the PUSCH and the corresponding uplink DMRS.

[0141] The base station may quasi-statistically configure the UE with one or more SRS configuration parameters indicating at least one of an SRS resource configuration identifier, the number of SRS ports, the time-domain behavior of the SRS resource configuration (e.g., indication of periodic, semi-persistent, or aperiodic SRS), slot, minislot, and / or subframe-level periodicity, an offset for periodic and / or aperiodic SRS resources, the number of OFDM symbols in the SRS resource, the start OFDM symbol of the SRS resource, the SRS bandwidth, the frequency hopping bandwidth, the periodic shift, and / or an SRS sequence ID.

[0142] Antenna ports are defined such that the channel on which a symbol on an antenna port is carried can be inferred from the channel on which another symbol on the same antenna port is carried. When a first symbol and a second symbol are transmitted on the same antenna port, a receiver may infer the channel (e.g., fade gain, multipath delay, and / or the like) on which a second symbol on the antenna port is carried from the channel on which the first symbol on the antenna port is carried. A first antenna port and a second antenna port may be referred to as quasi-colocated (QCL) if one or more large-scale characteristics of the channel on which the first symbol on the first antenna port is carried can be inferred from the channel on which the second symbol on the second antenna port is carried. The one or more large-scale characteristics may include at least one of delay spread, Doppler spread, Doppler shift, average gain, average delay, and / or spatial receive (Rx) parameters.

[0143] In a channel using beamforming, beam management is required. Beam management may include beam measurement, beam selection, and beam indication. A beam may be associated with one or more reference signals. For example, a beam may be identified by one or more beamforming reference signals. A UE may perform downlink beam measurement based on a downlink reference signal (e.g., a channel state information reference signal (CSI-RS)) and generate a beam measurement report. A UE may perform a downlink beam measurement procedure after an RRC connection is set up with a base station.

[0144] 11B shows an example of a channel state information reference signal (CSI-RS) mapped to the time and frequency domain. The squares shown in FIG. 11B may span resource blocks (RBs) within the bandwidth of a cell. The base station may transmit one or more RRC messages containing CSI-RS resource configuration parameters indicating one or more CSI-RS. One or more of the following parameters may be set by higher layer signaling (e.g., RRC and / or MAC signaling) for the CSI-RS resource configuration: CSI-RS resource configuration identity, number of CSI-RS ports, CSI-RS configuration (e.g., symbol and resource element (RE) location within a subframe), CSI-RS subframe configuration (e.g., subframe position, offset, and radio frame periodicity), CSI-RS power parameters, CSI-RS sequence parameters, code division multiplexing (CDM) type parameters, frequency density, transmit comb, quasi-colocation (QCL) parameters (e.g., QCL-scramblingidentity, crs-portscount, mbsfn-subframeconfiglist, csi-rs-configZPid, qcl-csi-rs-configNZPid), and / or other radio resource parameters.

[0145] The three beams shown in FIG. 11B may be configured for a UE with a UE-specific configuration. Three beams are shown in FIG. 11B (Beam #1, Beam #2, and Beam #3), and more or fewer beams may be configured. Beam #1 may be assigned with CSI-RS 1101, which may be transmitted on one or more subcarriers within the RB of the first symbol. Beam #2 may be assigned with CSI-RS 1102, which may be transmitted on one or more subcarriers within the RB of the second symbol. Beam #3 may be assigned with CSI-RS 1103, which may be transmitted on one or more subcarriers within the RB of the third symbol. By using frequency division multiplexing (FDM), the base station may transmit another CSI-RS associated with another UE's beam using other subcarriers within the same RB (e.g., those not used to transmit CSI-RS 1101). By using time domain multiplexing (TDM), the beam used for a UE may be configured so that the UE's beam uses symbols from the other UE's beam.

[0146] The CSI-RS (e.g., CSI-RS 1101, 1102, 1103) shown in FIG. 11B may be transmitted by a base station and used by a UE for one or more measurements. For example, the UE may measure the reference signal received power (RSRP) of configured CSI-RS resources. The base station may configure the UE with a reporting configuration, and the UE may report RSRP measurements to the network (e.g., via one or more base stations) based on the reporting configuration. In one embodiment, the base station may determine one or more transmission configuration indication (TCI) states, including several reference signals, based on the reported measurement results. In one embodiment, the base station may indicate one or more TCI states to the UE (e.g., via RRC signaling, MAC CE, and / or DCI). The UE may receive a downlink transmission with a receive (Rx) beam determined based on one or more TCI states. In an embodiment, the UE may or may not have beam correspondence capability. If the UE has beam correspondence capability, the UE may determine a spatial domain filter of a transmit (Tx) beam based on the spatial domain filter of the corresponding Rx beam. If the UE does not have beam correspondence capability, the UE may perform an uplink beam selection procedure to determine a spatial domain filter of the Tx beam. The UE may perform an uplink beam selection procedure based on one or more sounding reference signal (SRS) resources configured for the UE by the base station. The base station may select and indicate an uplink beam for the UE based on measurements of one or more SRS resources transmitted by the UE.

[0147] In a beam management procedure, a UE may evaluate (e.g., measure) the channel quality of one or more beam pair links, including a transmit beam transmitted by a base station and a receive beam received by the UE. Based on the evaluation, the UE may transmit a beam measurement report indicating one or more beam pair quality parameters, including, for example, one or more beam identities (e.g., beam index, reference signal index, or the like), RSRP, precoding matrix indicator (PMI), channel quality indicator (CQI), and / or rank indicator (RI).

[0148] FIG. 12A shows examples of three downlink beam management procedures, P1, P2, and P3. Procedure P1 may enable UE measurements at the transmit (Tx) beams of a transmit receive point (TRP) (or multiple TRPs) to support selection of one or more base station Tx beams and / or UE Rx beams (shown as ellipses in the top and bottom rows of P1, respectively). Beamforming at a TRP may include a Tx beam sweep of a set of beams (shown as an ellipse rotating counterclockwise as indicated by the dashed arrow in the top rows of P1 and P2). Beamforming at a UE may include an Rx beam sweep of a set of beams (shown as an ellipse rotating clockwise as indicated by the dashed arrow in the bottom rows of P1 and P3). Procedure P2 may be used to enable UE measurements at the Tx beams of a TRP (shown as an ellipse rotating counterclockwise as indicated by the dashed arrow in the top row of P2). The UE and / or base station may perform procedure P2 using a smaller set of beams than used in procedure P1 or using narrower beams than used in procedure P1. This may be referred to as beam refinement. The UE may perform procedure P3 for Rx beam determination by using the same Tx beam at the base station and sweeping the Rx beam at the UE.

[0149] FIG. 12B shows examples of three uplink beam management procedures, U1, U2, and U3. Procedure U1 may be used, for example, to enable the base station to perform measurements on the UE's Tx beams to support the selection of one or more UE Tx beams and / or base station Rx beams (shown as ellipses in the top and bottom rows of U1, respectively). Beamforming at the UE may include, for example, a Tx beam sweep from a set of beams (shown as an ellipse rotating clockwise as indicated by the dashed arrow in the bottom rows of U1 and U3). Beamforming at the base station may include, for example, an Rx beam sweep from a set of beams (shown as an ellipse rotating counterclockwise as indicated by the dashed arrow in the top rows of U1 and U2). Procedure U2 may be used to enable the base station to adjust its Rx beam when the UE uses a fixed Tx beam. The UE and / or base station may perform procedure U2 using a smaller set of beams than used in procedure P1 or using narrower beams than used in procedure P1. This may be referred to as beam refinement. The UE may perform procedure U3 to adjust its Tx beam when the base station uses a fixed Rx beam.

[0150] The UE may initiate a beam failure recovery (BFR) procedure based on the detection of a beam failure. The UE may transmit a BFR request (e.g., a preamble, UCI, SR, MAC CE, and / or the like) based on the initiation of the BFR procedure. The UE may detect beam failure based on determining that the quality of the beam pair link of the associated control channel is unsatisfactory (e.g., has an error rate higher than an error rate threshold, a received signal power lower than a received signal power threshold, a timer expiration, and / or the like).

[0151] A UE may measure the quality of a beam pair link using one or more reference signals (RSs), including one or more SS / PBCH blocks, one or more CSI-RS resources, and / or one or more demodulation reference signals (DMRSs). The quality of the beam pair link may be based on one or more of a block error rate (BLER), an RSRP value, a signal-to-interference-plus-noise ratio (SINR) value, a reference signal received quality (RSRQ) value, and / or a CSI value measured on the RS resources. The base station may indicate that an RS resource is quasi-co-located (QCLed) with one or more DM-RSs of a channel (e.g., a control channel, a shared data channel, and / or the like). The RS resource and one or more DMRSs of the channel may be QCLed when the channel characteristics (e.g., Doppler shift, Doppler spread, mean delay, delay spread, spatial Rx parameters, fading, and / or the like) from a transmission to the UE over the RS resource are similar or identical to the channel characteristics from a transmission to the UE over the channel.

[0152] The network (e.g., a gNB and / or ng-eNB of the network) and / or the UE may initiate a random access procedure. A UE in an RRC_IDLE state and / or a UE in an RRC_INACTIVE state may initiate a random access procedure to request connection setup to the network. A UE may initiate a random access procedure from an RRC_CONNECTED state. A UE may initiate a random access procedure to request uplink resources (e.g., for SR uplink transmission when there are no PUCCH resources available) and / or to acquire uplink timing (e.g., when the uplink synchronization state is not synchronized). A UE may initiate a random access procedure to request one or more system information blocks (SIBs) (e.g., SIB2, SIB3, and / or other system information such as the like). A UE may initiate a random access procedure for a beam failure recovery request. The network may initiate a random access procedure to establish time alignment for handover and / or for SCell addition.

[0153] Figure 13A shows a four-step contention-based random access procedure. Before the procedure begins, the base station may send a configuration message 1310 to the UE. Figure 13A includes the transmission of four messages: Msg1 1311, Msg2 1312, Msg3 1313, and Msg4 1314. Msg1 1311 may include and / or be referred to as a preamble (or random access preamble). Msg2 1312 may include and / or be referred to as a random access response (RAR).

[0154] The configuration message 1310 may be transmitted, for example, using one or more RRC messages. The one or more RRC messages may indicate one or more random access channel (RACH) parameters to the UE. The one or more RACH parameters may include at least one of general parameters (e.g., RACH-configGeneral), cell-specific parameters (e.g., RACH-ConfigCommon), and / or dedicated parameters (e.g., RACH-configDedicated) for one or more random access procedures. The base station may broadcast or multicast one or more RRC messages to one or more UEs. The one or more RRC messages may be UE-specific (e.g., dedicated RRC messages sent to the UE in RRC_CONNECTED and / or RRC_INACTIVE states). The UE may determine time-frequency resources and / or uplink transmit power for transmitting Msg1 1311 and / or Msg3 1313 based on the one or more RACH parameters. Based on one or more RACH parameters, the UE may determine the receive timing and downlink channel for receiving Msg2 1312 and Msg4 1314.

[0155] The one or more RACH parameters provided in the configuration message 1310 may indicate one or more physical RACH (PRACH) opportunities available for transmitting Msg1 1311. The one or more PRACH opportunities may be predefined. The one or more RACH parameters may indicate one or more available sets of one or more PRACH opportunities (e.g., prach-ConfigIndex). The one or more RACH parameters may indicate an association between (a) one or more PRACH opportunities and (b) one or more reference signals. The one or more RACH parameters may indicate an association between (a) one or more preambles and (b) one or more reference signals. The one or more reference signals may be SS / PBCH blocks and / or CSI-RS. For example, the one or more RACH parameters may indicate the number of SS / PBCH blocks mapped to the PRACH opportunity and / or the number of preambles mapped to the SS / PBCH block.

[0156] The one or more RACH parameters provided in the configuration message 1310 may be used to determine the uplink transmit power of Msg1 1311 and / or Msg3 1313. For example, the one or more RACH parameters may indicate a reference power for the preamble transmission (e.g., a received target power and / or an initial power of the preamble transmission). There may be one or more power offsets indicated by the one or more RACH parameters. For example, the one or more RACH parameters may indicate a power ramping step, a power offset between SSB and CSI-RS, a power offset between the transmissions of Msg1 1311 and Msg3 1313, and / or a power offset value between preamble groups. The one or more RACH parameters may indicate one or more thresholds from which the UE may determine at least one reference signal (e.g., SSB and / or CSI-RS) and / or uplink carrier (e.g., a normal uplink (NUL) carrier and / or a complementary uplink (SUL) carrier).

[0157] Msg1 1311 may include one or more preamble transmissions (e.g., a preamble transmission and one or more preamble retransmissions). An RRC message may be used to configure one or more preamble groups (e.g., Group A and / or Group B). A preamble group may include one or more preambles. The UE may determine the preamble group based on a path loss measurement and / or the size of Msg3 1313. The UE may measure the RSRP of one or more reference signals (e.g., SSB and / or CSI-RS) and determine at least one reference signal having an RSRP above an RSRP threshold (e.g., rsrp-threshold valueSSB and / or rsrp-ThresholdCSI-RS). The UE may select at least one preamble associated with one or more reference signals and / or a selected preamble group, for example, when an association between one or more preambles and at least one reference signal is configured by an RRC message.

[0158] The UE may determine a preamble based on one or more RACH parameters provided in the configuration message 1310. For example, the UE may determine a preamble based on a path loss measurement, an RSRP measurement, and / or the size of Msg3 1313. As another example, the one or more RACH parameters may indicate one or more thresholds for determining a preamble format, a maximum number of preamble transmissions, and / or one or more preamble groups (e.g., Group A and Group B). The base station may configure the UE with an association between one or more preambles and one or more reference signals (e.g., SSB and / or CSI-RS) using the one or more RACH parameters. If an association is configured, the UE may determine a preamble to include in Msg1 1311 based on the association. Msg1 1311 may be transmitted to the base station via one or more PRACH opportunities. The UE may use one or more reference signals (e.g., SSB and / or CSI-RS) for preamble selection and PRACH opportunity determination. One or more RACH parameters (eg, ra-ssb-OccasionMskIndex and / or ra-OccasionList) may indicate an association between a PRACH occasion and one or more reference signals.

[0159] The UE may perform a preamble retransmission if no response is received after the preamble transmission. The UE may increase uplink transmit power for the preamble retransmission. The UE may select an initial preamble transmit power based on a path loss measurement and / or a target received preamble power configured by the network. The UE may determine to retransmit the preamble and may ramp up the uplink transmit power. The UE may receive one or more RACH parameters (e.g., PREAMBLE_POWER_RAMPING_STEP) indicating a ramping step for the preamble retransmission. The ramping step may be the amount of incremental increase in uplink transmit power for the retransmission. If the UE determines a reference signal (e.g., SSB and / or CSI-RS) to be the same as the previous preamble transmission, the UE may ramp up the uplink transmit power. The UE may count the number of preamble transmissions and / or retransmissions (e.g., PREAMBLE_TRANSMISSION_COUNTER). The UE may determine that the random access procedure has completed unsuccessfully, for example, if the number of preamble transmissions exceeds a threshold configured by one or more RACH parameters (e.g., preambleTransMax).

[0160] Msg2 1312 received by the UE may include an RAR. In some scenarios, Msg2 1312 may include multiple RARs corresponding to multiple UEs. Msg2 1312 may be received after or in response to the transmission of Msg1 1311. Msg2 1312 may be scheduled on the DL-SCH and indicated on the PDCCH using the Random Access RNTI (RA-RNTI). Msg2 1312 may indicate that Msg1 1311 has been received by the base station. Msg2 1312 may include a time alignment command that the UE may use to adjust its transmission timing, a scheduling grant for the transmission of Msg3 1313, and / or a Temporary Cell RNTI (TC-RNTI). After the UE transmits the preamble, the UE may start a time window (e.g., ra-ResponseWindow) in which it monitors the PDCCH for Msg2 1312. The UE may determine when to start the time window based on the PRACH opportunity the UE uses to transmit the preamble. For example, the UE may start the time window one or more symbols after the last symbol of the preamble (e.g., on the first PDCCH opportunity from the end of the preamble transmission). The one or more symbols may be determined based on numerology. The PDCCH may be within a common search space configured by an RRC message (e.g., a Type1-PDCCH common search space). The UE may identify the RAR based on a radio network temporary identifier (RNTI). The RNTI may be used in response to one or more events that initiate a random access procedure. The UE may use a random access RNTI (RA-RNTI). The RA-RNTI may be associated with the PRACH opportunity on which the UE transmits the preamble. For example, the UE may determine the RA-RNTI based on an OFDM symbol index, a slot index, a frequency domain index, and / or an UL carrier indicator of the PRACH opportunity. Examples of the RA-RNTI may be as follows: RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id where s_id may be the index of the first OFDM symbol of the PRACH opportunity (e.g., 0≦s_id<14), t_id may be the index of the first slot of the PRACH opportunity within the system frame (e.g., 0≦t_id<80), f_id may be the index of the PRACH opportunity in the frequency domain (e.g., 0≦f_id<8), and ul_carrier_id may be the UL carrier used for preamble transmission (e.g., 0 for NUL carrier and 1 for SUL carrier). The UE may transmit Msg3 1313 in response to successful reception of Msg2 1312 (e.g., using the resources identified in Msg2 1312). Msg3 1313 may be used for contention resolution, for example, in the contention-based random access procedure shown in FIG. 13A. In some scenarios, multiple UEs may transmit the same preamble to the base station, and the base station may provide the UE with a corresponding RAR. If multiple UEs interpret the RAR as corresponding to themselves, a mismatch may occur. Contention resolution (e.g., use of Msg3 1313 and Msg4 1314) may be used to increase the likelihood that a UE will not mistakenly use the identity of another UE. To perform contention resolution, the UE may include a device identifier (e.g., C-RNTI, if assigned, TC-RNTI included in Msg2 1312, and / or any other suitable identifier) ​​in Msg3 1313.

[0161] Msg4 1314 may be received after or in response to the transmission of Msg3 1313. If a C-RNTI was included in Msg3 1313, the base station addresses the UE on the PDCCH using the C-RNTI. If the UE's unique C-RNTI is detected on the PDCCH, the random access procedure is determined to have completed successfully. If a TC-RNTI is included in Msg3 1313 (e.g., the UE is in an RRC_IDLE state or is otherwise not connected to the base station), Msg4 1314 is received using the DL-SCH associated with the TC-RNTI. If the MAC PDU is successfully decoded and the MAC PDU matches the CCCH SDU sent (e.g., transmitted) in Msg3 1313 or otherwise includes the corresponding UE contention resolution identity MAC CE, the UE may determine that contention resolution was successful and / or the UE may determine that the random access procedure was completed successfully.

[0162] A UE may be configured with a complementary uplink (SUL) carrier and a normal uplink (NUL) carrier. Initial access (e.g., random access procedure) may be supported on the uplink carrier. For example, a base station may configure a UE with two separate RACH configurations, one for the SUL carrier and one for the NUL carrier. For random access in a cell configured with the SUL carrier, the network may indicate which carrier (NUL or SUL) to use. The UE may determine the SUL carrier, for example, if the measured quality of one or more reference signals is lower than a broadcast threshold. Uplink transmissions of the random access procedure (e.g., Msg1 1311 and / or Msg3 1313) may remain on the selected carrier. The UE may switch uplink carriers during the random access procedure (e.g., between Msg1 1311 and Msg3 1313) in one or more instances. For example, the UE may determine and / or switch the uplink carrier for Msg1 1311 and / or Msg3 1313 based on a channel clear assessment (eg, listen-before-talk).

[0163] Figure 13B shows a two-step contention-free random access procedure. Similar to the four-step contention-based random access procedure shown in Figure 13A, the base station may transmit a configuration message 1320 to the UE before the procedure begins. The configuration message 1320 may be similar in some respects to the configuration message 1310. Figure 13B includes the transmission of two messages, Msg1 1321 and Msg2 1322. Msg1 1321 and Msg2 1322 may be similar in some respects to Msg1 1311 and Msg2 1312, respectively, shown in Figure 13A. As can be seen from Figures 13A and 13B, the contention-free random access procedure may not include messages similar to Msg3 1313 and / or Msg4 1314.

[0164] The contention-free random access procedure shown in Figure 13B may be initiated for beam failure recovery, other SI requests, SCell addition, and / or handover. For example, the base station may indicate or assign to the UE the preamble to be used for Msg1 1321. The UE may receive an indication of the preamble (e.g., ra-PreambleIndex) from the base station via PDCCH and / or RRC.

[0165] After transmitting the preamble, the UE may start a time window (e.g., ra-ResponseWindow) in which it monitors the PDCCH for the RAR. In the case of a beam failure recovery request, the base station may configure the UE with a separate time window and / or a separate PDCCH within the search space indicated by the RRC message (e.g., recoverySearchSpaceId). The UE may monitor for PDCCH transmissions addressed to the Cell RNTI (C-RNTI) over the search space. In the contention-free random access procedure shown in FIG. 13B, the UE may determine that the random access procedure has completed successfully after or in response to transmitting Msg1 1321 and receiving the corresponding Msg2 1322. The UE may determine that the random access procedure has completed successfully, for example, if the PDCCH transmission is addressed to the C-RNTI. The UE may determine that the random access procedure is successfully completed, for example, if the UE receives an RAR including a preamble identifier corresponding to the preamble transmitted by the UE and / or if the RAR includes a MAC sub-PDU including the preamble identifier. The UE may determine the response as an indication of a response acknowledgment to the SI request.

[0166] 13C shows another two-step random access procedure. Similar to the random access procedures shown in FIG. 13A and FIG. 13B, the base station may send a configuration message 1330 to the UE before the procedure begins. The configuration message 1330 may be similar in some respects to the configuration message 1310 and / or the configuration message 1320. FIG. 13C includes the transmission of two messages, namely, MsgA 1331 and MsgB 1332.

[0167] MsgA 1331 may be transmitted in an uplink transmission by the UE. MsgA 1331 may include one or more transmissions of preamble 1341 and / or one or more transmissions of transport block 1342. Transport block 1342 may include content similar and / or equivalent to the content of Msg3 1313 shown in FIG. 13A. Transport block 1342 may include UCI (e.g., SR, HARQ ACK / NACK, and / or similar). The UE may receive MsgB 1332 after or in response to the transmission of MsgA 1331. MsgB 1332 may include content similar and / or equivalent to the content of Msg2 1312 (e.g., RAR) shown in FIG. 13A and FIG. 13B and / or the content of Msg4 1314 shown in FIG. 13A.

[0168] The UE may initiate the two-step random access procedure of Figure 13C for licensed and / or unlicensed spectrum. The UE may determine whether to initiate the two-step random access procedure based on one or more factors. The one or more factors may be the radio access technology in use (e.g., LTE, NR, and / or similar), whether the UE has a valid TA, the cell size, the RRC state of the UE, the type of spectrum (e.g., licensed vs. unlicensed), and / or any other suitable factor.

[0169] The UE may determine radio resources and / or uplink transmit power for the preamble 1341 and / or the transport block 1342 included in MsgA 1331 based on the two-step RACH parameters included in the configuration message 1330. The RACH parameters may indicate a modulation and coding scheme (MCS), time-frequency resources, and / or power control for the preamble 1341 and / or the transport block 1342. The time-frequency resources for transmission of the preamble 1341 (e.g., PRACH) and the time-frequency resources for transmission of the transport block 1342 (e.g., PUSCH) may be multiplexed using FDM, TDM, and / or CDM. The RACH parameters may enable the UE to determine the receive timing and downlink channel for monitoring and / or receiving MsgB 1332.

[0170] The transport block 1342 may include data (e.g., delay-sensitive data), a UE identifier, security information, and / or device information (e.g., International Mobile Subscriber Identity (IMSI)). The base station may transmit MsgB 1332 in response to MsgA 1331. MsgB 1332 may include at least one of a preamble identifier, a timing advance command, a power control command, an uplink grant (e.g., a radio resource allocation and / or MCS), a UE identifier for contention resolution, and / or an RNTI (e.g., C-RNTI or TC-RNTI). The UE may determine that the two-step random access procedure is successfully completed when the preamble identifier in MsgB 1332 matches the preamble transmitted by the UE and / or the UE identifier in MsgB 1332 matches the UE identifier (e.g., transport block 1342) in MsgA 1331.

[0171] The UE and the base station may exchange control signaling, which may be referred to as L1 / L2 control signaling and may originate from the PHY layer (e.g., Layer 1) and / or the MAC layer (e.g., Layer 2). The control signaling may include downlink control signaling transmitted from the base station to the UE and / or uplink control signaling transmitted from the UE to the base station.

[0172] The downlink control signaling may include downlink scheduling assignments, uplink scheduling grants indicating uplink radio resources and / or transport formats, slot format information, preemption indications, power control commands, and / or any other suitable signaling. A UE may receive the downlink control signaling in a payload transmitted by a base station on a physical downlink control channel (PDCCH). The payload transmitted on the PDCCH may be referred to as downlink control information (DCI). In some scenarios, the PDCCH may be a group-common PDCCH (GC-PDCCH) that is common to a group of UEs.

[0173] The base station may attach one or more cyclic redundancy check (CRC) parity bits to the DCI to facilitate detection of transmission errors. When the DCI is intended for a UE (or a group of UEs), the base station may scramble the CRC parity bits with an identifier of the UE (or an identifier of the group of UEs). Scrambling the CRC parity bits with the identifier may include a modulo-2 addition (or exclusive-OR operation) of the identifier value and the CRC parity bits. The identifier may include a 16-bit value, a Radio Network Temporary Identifier (RNTI).

[0174] DCIs may be used for different purposes. The purpose may be indicated by the type of RNTI used to scramble the CRC parity bits. For example, a DCI with CRC parity bits scrambled with a paging RNTI (P-RNTI) may indicate paging information and / or system information change notification. The P-RNTI may be predefined as "FFFE" in hexadecimal. A DCI with CRC parity bits scrambled with a system information RNTI (SI-RNTI) may indicate a broadcast transmission of system information. The SI-RNTI may be predefined as "FFFF" in hexadecimal. A DCI with CRC parity bits scrambled with a random access RNTI (RA-RNTI) may indicate a random access response (RAR). A DCI with CRC parity bits scrambled with a cell RNTI (C-RNTI) may indicate a unicast transmission of dynamic scheduling and / or a random access of PDCCH order trigger. A DCI with CRC parity bits scrambled with the Temporary Cell RNTI (TC-RNTI) may indicate contention resolution (e.g., Msg3 similar to Msg3 1313 shown in FIG. 13A). Encodings of other RNTIs configured in the UE by the base station include Configured Scheduling RNTI (CS-RNTI), Transmit Power Control-PUCCH RNTI (TPC-PUCCH-RNTI), Transmit Power Control-PUSCH RNTI (TPC-PUSCH-RNTI), Transmit Power Control-SRS RNTI (TPC-SRS-RNTI), Interruption RNTI (INT-RNTI), Slot Format Indication RNTI (SFI-RNTI), Semi-Persistent CSI RNTI (SP-CSI-RNTI), Modulation and Coding Scheme Cell RNTI (MCS-C-RNTI), and / or the like.

[0175] Depending on the purpose and / or content of the DCI, a base station may transmit the DCI in one or more DCI formats. For example, DCI format 0_0 may be used for scheduling the PUSCH in a cell. DCI format 0_0 may be a fallback DCI format (e.g., has a compact DCI payload). DCI format 0_1 ​​may be used for scheduling the PUSCH in a cell (e.g., has a larger DCI payload than DCI format 0_0). DCI format 1_0 may be used for scheduling the PDSCH in a cell. DCI format 1_0 may be a fallback DCI format (e.g., has a compact DCI payload). DCI format 1_1 may be used for scheduling the PDSCH in a cell (e.g., has a larger DCI payload than DCI format 1_0). DCI format 2_0 may be used to provide a slot format indication to a group of UEs. DCI format 2_1 may be used to inform a group of UEs of physical resource blocks and / or OFDM symbols that the UE assumes are not intended for transmission to the UEs. DCI format 2_2 may be used for transmission of transmit power control (TPC) commands for PUCCH or PUSCH. DCI format 2_3 may be used for transmission of a group of TPC commands for SRS transmission by one or more UEs. DCI formats for new features may be defined in future releases. DCI formats may have different DCI sizes or share the same DCI size.

[0176] After scrambling the DCI with the RNTI, the base station may process the DCI with channel coding (e.g., polar coding), rate matching, scrambling, and / or QPSK modulation. The base station may map the coded and modulated DCI onto resource elements used and / or configured for the PDCCH. Based on the payload size of the DCI and / or the base station's coverage, the base station may transmit the DCI via the PDCCH occupying several consecutive control channel elements (CCEs). The number of consecutive CCEs (referred to as the aggregation level) may be 1, 2, 4, 8, 16, and / or any other suitable number. A CCE may include a number of resource element groups (REGs) (e.g., 6). A REG may include a resource block in an OFDM symbol. The mapping of the coded and modulated DCI onto resource elements may be based on a mapping of CCEs and REGs (e.g., CCE to REG mapping).

[0177] FIG. 14A shows an example of a CORESET configuration for a bandwidth portion. A base station may transmit DCI via a PDCCH on one or more control resource sets (CORESETs). A CORESET may include time-frequency resources on which a UE attempts to decode the DCI using one or more search spaces. A base station may configure CORESETs in the time-frequency domain. In the example of FIG. 14A, a first CORESET 1401 and a second CORESET 1402 occur at the first symbol in a slot. The first CORESET 1401 overlaps with the second CORESET 1402 in the frequency domain. The third CORESET 1403 occurs at the third symbol in the slot. The fourth CORESET 1404 occurs at the seventh symbol of the slot. The CORESETs may have different numbers of resource blocks in the frequency domain.

[0178] FIG. 14B shows an example of CCE-to-REG mapping for DCI transmission on a CORESET and PDCCH processing. The CCE-to-REG mapping may be interleaved (e.g., to provide frequency diversity) or non-interleaved (e.g., to facilitate interference coordination and / or frequency-selective transmission of control channels). A base station may implement different or the same CCE-to-REG mapping on different CORESETs. A CORESET may be associated with a CCE-to-REG mapping by RRC configuration. A CORESET may be configured with an antenna port quasi-co-location (QCL) parameter. The QCL parameter of an antenna port may indicate QCL information of a demodulation reference signal (DMRS) for PDCCH reception within the CORESET.

[0179] The base station may send an RRC message to the UE including configuration parameters for one or more CORESETs and one or more search space sets. The configuration parameters may indicate an association between the search space set and the CORESET. The search space set may include a set of PDCCH candidates formed by CCEs at a given aggregation level. The configuration parameters may indicate the number of PDCCH candidates to be monitored per aggregation level, a PDCCH monitoring periodicity and PDCCH monitoring pattern, one or more DCI formats to be monitored by the UE, and / or whether the search space set is a common search space set or a UE-specific search space set. The set of CCEs in the common search space set may be predefined and known to the UE. The set of CCEs in the UE-specific search space set may be configured based on the UE's identity (e.g., C-RNTI).

[0180] As shown in FIG. 14B, the UE may determine time-frequency resources of the CORESET based on the RRC message. The UE may determine CCE-REG mapping (e.g., interleaved or non-interleaved, and / or mapping parameters) for the CORESET based on configuration parameters of the CORESET. The UE may determine the number of search space sets (e.g., up to 10) configured on the CORESET based on the RRC message. The UE may monitor a set of PDCCH candidates according to the configuration parameters of the search space sets. The UE may monitor a set of PDCCH candidates in one or more CORESETs to detect one or more DCIs. The monitoring may include decoding one or more PDCCH candidates of the set of PDCCH candidates according to the monitored DCI format. The monitoring may include decoding DCI content of one or more PDCCH candidates having possible (or configured) PDCCH positions, possible (or configured) PDCCH formats (e.g., the number of CCEs in the common search space, the number of PDCCH candidates, and / or the number of PDCCH candidates in the UE-specific search space), and possible (or configured) DCI formats. The decoding may be referred to as blind decoding. The UE may determine a valid DCI for the UE in response to a CRC check (e.g., scrambling bits against CRC parity bits of the DCI matching the RNTI value). The UE may process information included in the DCI (e.g., scheduling assignment, uplink grant, power control, slot format indication, downlink preemption, and / or the like).

[0181] The UE may transmit uplink control signaling (e.g., uplink control information (UCI)) to the base station. The uplink control signaling may include a hybrid automatic repeat request (HARQ) acknowledgment for a received DL-SCH transport block. The UE may transmit the HARQ acknowledgment after receiving the DL-SCH transport block. The uplink control signaling may include channel state information (CSI) indicating the channel quality of the physical downlink channel. The UE may transmit the CSI to the base station. The base station may determine transmit format parameters (e.g., including multiple antennas and a forming scheme) for the downlink transmission based on the received CSI. The uplink control signaling may include a scheduling request (SR). The UE may transmit the SR indicating that uplink data is available for transmission to the base station. The UE may transmit the UCI (e.g., a HARQ acknowledgment (HARQ-ACK), a CSI report, an SR, etc.) via a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). A UE may transmit uplink control signaling via the PUCCH using one of several PUCCH formats.

[0182] There may be five PUCCH formats, and the UE may determine the PUCCH format based on the size of the UCI (e.g., the number of uplink symbols for UCI transmission and the number of UCI bits). PUCCH format 0 may have a length of one or two OFDM symbols and may contain two or fewer bits. The UE may transmit UCI on PUCCH resources using PUCCH format 0 if the transmission is more than one or two symbols and the number of HARQ-ACK information bits with positive or negative SR (HARQ-ACK / SR bits) is one or two. PUCCH format 1 may occupy between four and fourteen OFDM symbols and may contain two or fewer bits. The UE may use PUCCH format 1 if the transmission is four or more symbols and the number of HARQ-ACK / SR bits is one or two. PUCCH format 2 may occupy one or two OFDM symbols and may contain more than two bits. The UE may use PUCCH format 2 if the transmission is more than one or two symbols and the number of UCI bits is two or more. PUCCH format 3 may occupy between 4 and 14 OFDM symbols and may include more than 2 bits. A UE may use PUCCH format 3 if the transmission is four or more symbols, the number of UCI bits is two or more, and the PUCCH resource does not include an orthogonal cover code. PUCCH format 4 may occupy between 4 and 14 OFDM symbols and may include more than 2 bits. A UE may use PUCCH format 4 if the transmission is four or more symbols, the number of UCI bits is two or more, and the PUCCH resource includes an orthogonal cover code.

[0183] The base station may transmit configuration parameters for multiple PUCCH resource sets to the UE, for example, using an RRC message. Multiple PUCCH resource sets (e.g., up to four sets) may be configured on the uplink BWP of the cell. A PUCCH resource set may be configured with a PUCCH resource set index, multiple PUCCH resources with the PUCCH resource identified by a PUCCH resource identifier (e.g., pucch-Resourceid), and / or the number (e.g., maximum number) of UCI information bits that the UE may transmit using one of the multiple PUCCH resources in the PUCCH resource set. When configured with multiple PUCCH resource sets, the UE may select one of the multiple PUCCH resource sets based on the total bit length of the UCI information bits (e.g., HARQ-ACK, SR, and / or CSI). If the total bit length of the UCI information bits is two or less, the UE may select the first PUCCH resource set whose PUCCH resource set index is equal to "0." If the total bit length of the UCI information bits is greater than 2 and less than or equal to the first configuration value, the UE may select a second PUCCH resource set having a PUCCH resource set index equal to '1'. If the total bit length of the UCI information bits is greater than the first configuration value and less than or equal to the second configuration value, the UE may select a third PUCCH resource set having a PUCCH resource set index equal to '2'. If the total bit length of the UCI information bits is greater than the second configuration value and less than or equal to a third value (e.g., 1406), the UE may select a fourth PUCCH resource set having a PUCCH resource set index equal to '3'.

[0184] After determining a PUCCH resource set from the multiple PUCCH resource sets, the UE may determine a PUCCH resource from the PUCCH resource set for UCI (HARQ-ACK, CSI, and / or SR) transmission. The UE may determine the PUCCH resource based on a PUCCH resource indicator in DCI (e.g., DCI format 1_0 or DCI format 1_1) received on the PDCCH. The 3-bit PUCCH resource indicator in the DCI may indicate one of eight PUCCH resources in the PUCCH resource set. Based on the PUCCH resource indicator, the UE may transmit UCI (HARQ-ACK, CSI, and / or SR) using the PUCCH resource indicated by the PUCCH resource indicator in the DCI.

[0185] 15 illustrates an example of a wireless device 1502 communicating with a base station 1504 according to an embodiment of the present disclosure. The wireless device 1502 and the base station 1504 may be part of a mobile communication network, such as the mobile communication network 100 shown in FIG. 1A, the mobile communication network 150 shown in FIG. 1B, or another communication network. While only one wireless device 1502 and one base station 1504 are shown in FIG. 15, it will be understood that a mobile communication network may include more than one UE and / or more than one base station having the same or similar configuration as that shown in FIG. 15.

[0186] The base station 1504 may connect the wireless device 1502 to a core network (not shown) via wireless communication over an air interface (or radio interface) 1506. The direction of communication from the base station 1504 to the wireless device 1502 over the air interface 1506 is known as the downlink, and the direction of communication from the wireless device 1502 to the base station 1504 over the air interface is known as the uplink. Downlink transmissions may be separated from uplink transmissions using FDD, TDD, and / or some combination of the two duplexing techniques.

[0187] On the downlink, data transmitted from the base station 1504 to the wireless device 1502 may be provided to the processing system 1508 of the base station 1504. The data may be provided to the processing system 1508 by, for example, a core network. On the uplink, data transmitted from the wireless device 1502 to the base station 1504 may be provided to the processing system 1518 of the wireless device 1502. The processing system 1508 and the processing system 1518 may implement Layer 3 and Layer 2 OSI functions to process the data for transmission. Layer 2 may include, for example, the SDAP layer, the PDCP layer, the RLC layer, and the MAC layer with respect to Figures 2A, 2B, 3, and 4A. Layer 3 may include the RRC layer with respect to Figure 2B.

[0188] After being processed by processing system 1508, data to be transmitted to wireless device 1502 may be provided to transmit processing system 1510 of base station 1504. Similarly, after being processed by processing system 1518, data to be transmitted to base station 1504 may be provided to transmit processing system 1520 of wireless device 1502. Transmit processing system 1510 and transmit processing system 1520 may implement the OSI functions of Layer 1. Layer 1 may include the PHY layer with respect to FIGS. 2A, 2B, 3, and 4A. For transmit processing, the PHY layer may perform, for example, forward error correction coding of transport channels, interleaving, rate matching, mapping of transport channels to physical channels, modulation of physical channels, multiple-input multiple-output (MIMO) or multi-antenna processing, and / or the like.

[0189] At the base station 1504, a receive processing system 1512 may receive uplink transmissions from the wireless device 1502. At the wireless device 1502, a receive processing system 1522 may receive downlink transmissions from the base station 1504. The receive processing system 1512 and the receive processing system 1522 may implement the OSI functions of Layer 1. Layer 1 may include the PHY layer with respect to FIGS. 2A, 2B, 3, and 4A. For receive processing, the PHY layer may perform, for example, error detection, forward error correction decoding, deinterleaving, demapping of transport channels to physical channels, demodulation of the physical channels, MIMO or multi-antenna processing, and / or the like.

[0190] 15, the wireless device 1502 and the base station 1504 may include multiple antennas. The multiple antennas may be used to implement one or more MIMO or multi-antenna techniques, such as spatial multiplexing (e.g., single-user MIMO or multi-user MIMO), transmit / receive diversity, and / or beamforming. In other examples, the wireless device 1502 and / or the base station 1504 may have a single antenna.

[0191] Processing system 1508 and processing system 1518 may be associated with memory 1514 and memory 1524, respectively. Memory 1514 and memory 1524 (e.g., one or more non-transitory computer-readable media) may store computer program instructions or code that may be executed by processing system 1508 and / or processing system 1518 to perform one or more functions discussed herein. Although not shown in FIG. 15 , transmit processing system 1510, transmit processing system 1520, receive processing system 1512, and / or receive processing system 1522 may be coupled to memory (e.g., one or more non-transitory computer-readable media) that stores computer program instructions or code that may be executed to perform one or more of their respective functions.

[0192] The processing system 1508 and / or the processing system 1518 may include one or more controllers and / or one or more processors. The one or more controllers and / or the one or more processors may include, for example, a general-purpose processor, a digital signal processor (DSP), a microcontroller, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) and / or other programmable logic devices, discrete gate and / or transistor logic, discrete hardware components, on-board units, or any combination thereof. The processing system 1508 and / or the processing system 1518 may perform at least one of signal coding / processing, data processing, power control, input / output processing, and / or any other functionality that may enable the wireless device 1502 and the base station 1504 to operate in a wireless environment.

[0193] Processing system 1508 and / or processing system 1518 may be connected to one or more peripheral devices 1516 and one or more peripheral devices 1526, respectively. The one or more peripheral devices 1516 and one or more peripheral devices 1526 may include software and / or hardware that provide features and / or functionality, such as a speaker, a microphone, a keypad, a display, a touchpad, a power supply, a satellite transceiver, a universal serial bus (USB) port, a hands-free headset, a frequency modulation (FM) radio unit, a media player, an internet browser, an electronic control unit (e.g., for a vehicle), and / or one or more sensors (e.g., an accelerometer, a gyroscope, a temperature sensor, a radar sensor, a lidar sensor, an ultrasonic sensor, a light sensor, a camera, and / or the like). Processing system 1508 and / or processing system 1518 may receive user input data and / or provide user output data from the one or more peripheral devices 1516 and / or one or more peripheral devices 1526. The processing system 1518 in the wireless device 1502 can receive power from a power source and / or can be configured to distribute power to other components in the wireless device 1502. The power source can include one or more power sources, such as a battery, a solar cell, a fuel cell, or any combination thereof. The processing system 1508 and / or the processing system 1518 can be connected to a GPS chipset 1517 and a GPS chipset 1527, respectively. The GPS chipset 1517 and the GPS chipset 1527 can be configured to provide geographic location information for the wireless device 1502 and the base station 1504, respectively.

[0194] Figure 16A shows an example structure for uplink transmission. A baseband signal representing a physical uplink shared channel may perform one or more functions. The one or more functions may include at least one of scrambling, modulation of scramble bits to generate complex-valued symbols, mapping of complex-valued modulation symbols onto one or several transmission layers, transform precoding to generate complex-valued symbols, precoding of the complex-valued symbols, mapping of the precoded complex-valued symbols to resource elements, generation of complex-valued time-domain single-carrier frequency-division multiple access (SC-FDMA) or CP-OFDM signals to antenna ports, and / or the like. In an example, if transform precoding is enabled, an SC-FDMA signal for uplink transmission may be generated. In an example, if transform precoding is not enabled, a CP-OFDM signal for uplink transmission may be generated according to Figure 16A. These functions are shown as examples, and it is anticipated that other mechanisms may be implemented in various embodiments.

[0195] 16B shows an example structure for modulation and upconversion of a base-band signal to a carrier frequency. The base-band signal may be a complex-valued SC-FDMA or CP-OFDM base-band signal and / or a complex-valued Physical Random Access Channel (PRACH) base-band signal for an antenna port. Filtering may be used before transmission.

[0196] 16C shows an example structure of a downlink transmission. The baseband signal representing the physical downlink channel can perform one or more functions. The one or more functions may include scrambling coded bits in a codeword to be transmitted on the physical channel, modulating the scrambled bits to generate complex-valued modulation symbols, mapping the complex-valued modulation symbols onto one or more transmission layers, precoding the complex-valued modulation symbols on the layers for transmission on the antenna ports, mapping the complex-valued modulation symbols of the antenna ports to resource elements, generating a complex-valued time-domain OFDM signal per antenna port, and / or the like. These functions are shown as examples, and it is anticipated that other mechanisms may be implemented in various embodiments.

[0197] 16D shows another exemplary structure for modulation and upconversion of a base-band signal to a carrier frequency. The base-band signal may be a complex-valued OFDM base-band signal for an antenna port. Filtering may be used before transmission.

[0198] A wireless device may receive one or more messages (e.g., RRC messages) from a base station including configuration parameters for multiple cells (e.g., a primary cell, a secondary cell). The wireless device may communicate with at least one base station (e.g., two or more base stations for dual connectivity) via the multiple cells. The one or more messages (e.g., as part of the configuration parameters) may include physical, MAC, RLC, PCDP, SDAP, and RRC layer parameters for configuring the wireless device. For example, the configuration parameters may include parameters for configuring physical and MAC layer channels, bearers, etc. For example, the configuration parameters may include parameters indicating timer values ​​for the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, RRC layer, and / or communication channels.

[0199] When a timer is started, it begins running and may continue running until it is stopped or expires. A timer may be started if it is not running or restarted if it is running. A timer may be associated with a value (e.g., a timer may be started or restarted from a value, or may start from zero and expire when the value is reached). A timer's duration may not be updated until the timer is stopped or expires (e.g., due to a BWP switch). A timer may be used to measure a time period / window for a process. When this specification refers to implementations and procedures related to one or more timers, it will be understood that there are multiple ways to implement one or more timers. For example, it will be understood that one or more of multiple ways to implement a timer may be used to measure a time period / window for a procedure. For example, a random access response window timer may be used to measure a window time for receiving a random access response. In an embodiment, the time difference between two timestamps may be used instead of the start and expiration of the random access response window timer. When the timer is restarted, the process for measuring the time window may be restarted. Another example implementation may be provided for restarting the measurement of the time window.

[0200] A UE may access a cell as a portion of a frequency spectrum for wireless communication. The UE may receive a broadcast signal including cell access information, e.g., a synchronization signal block (SSB) and / or a system information block (SIB, e.g., SIB1). A cell, e.g., a serving cell, may be associated with one or more SSBs. SIB1 (e.g., transmitted by one or more SSBs) may indicate frequency information of the serving cell (e.g., via the servingCellConfigCommon and / or servingCellConfigCommonSIBs). The serving cell may include a downlink (DL) carrier and one or more uplink (UL) carriers (e.g., (normal) UL and / or supplemental UL). The serving cell configuration includes the downlink configuration of the DL carrier (e.g., via the downlinkConfigCommon and / or downlinkConfigCommonSIBs) and / or the uplink configuration of one or more UL carriers of the cell (e.g., the uplinkConfigCommon and / or uplinkConfigCommonSIBs). A carrier may be referred to as a component carrier.

[0201] Throughout this disclosure, uplink (UL) may refer to communications directed from a mobile / wireless device to a base station / network, and downlink (DL) may refer to communications directed from a base station / network to a mobile / wireless device / UE.

[0202] The downlink configuration may indicate basic parameters of the DL carrier and transmissions thereon, including the DL carrier's frequency information. The DL carrier's frequency information may indicate a list of one or more frequency bands to which the DL carrier belongs (e.g., via frequencyBandList), the DL carrier's offset to Point A (offsetToPointA), and / or a set of carriers for different subcarrier spacings (SCS, numerology) used in the serving cell's DL BWP. Multiple bands may be defined, e.g., for 5G and / or 6G, each with a respective center frequency. Each band (e.g., n1, n2, ..., n25, n26, ..., n99 for FR1 and n257, n258, ..., nFR262 for FR2) may be defined with a duplex mode (TDD and / or FDD), a range of uplink and downlink frequencies, and an allowed channel bandwidth (e.g., 5 MHz, 10 MHz, ..., 50 MHz, 200 MHz, 400 MHz).

[0203] A frequency band can be a range of frequencies in the spectrum between two limits used for communications. A frequency band can be a range of frequencies defined and dedicated to a particular type of service or radio technology. The 5G New Radio (5G NR) frequency band can be separated into two distinct frequency ranges. First, there is Frequency Range 1 (FR1), which includes sub-6 GHz frequency bands, some of which are traditionally used by legacy standards but which are expanded to cover potential new spectrum offerings (e.g., 410 MHz to 7125 MHz). The other is Frequency Range 2 (FR2), which includes the frequency band from 24.25 GHz to 52.6 GHz. In one example, a frequency band can be defined for FR3 (e.g., above 72 GHz).

[0204] A DL carrier consists of one or more DL Bandwidth Parts (BWPs). Each DL BWP may include a portion of the frequency resources of the DL carrier. A DL BWP configuration may indicate the frequency domain location and bandwidth of this BWP, as well as the SCS used in the BWP of (all) channels and (reference) signals.

[0205] The uplink configuration may indicate basic parameters of the UL carrier (e.g., the NUL carrier and / or the SUL carrier) and transmissions thereon, including the frequency information of the UL carrier, which may indicate a list of one or more frequency bands to which the UL carrier belongs (e.g., via frequencyBandList), the absolute frequency of the reference resource block (a common RB0, e.g., via absoluteFrequencyPointA, whose lowest subcarrier may be referred to as point A), and / or a set of carriers with different subcarrier spacings (SCS, numerology) used in the UL BWP of the serving cell and / or UL carrier.

[0206] A UL carrier (e.g., a NUL carrier and / or a SUL carrier) may include one or more UL Bandwidth Portions (BWPs). Each UL BWP may include a portion of the frequency resources of the UL carrier. A UL BWP configuration may indicate the frequency domain location and bandwidth of this BWP, as well as the SCS used in the BWP for (all) channels and (reference) signals.

[0207] An architectural consideration is dual connectivity (DC) operation involving a first RAT (e.g., Enhanced Universal Terrestrial Radio Access (E-UTRA)) and a second RAT (e.g., NR). In one example of dual connectivity (DC) operation involving E-UTRA and NR, E-UTRA is the master. In another example of DC operation involving E-UTRA and NR, NR is the master. Dual connectivity operation involving only NR serving cells (e.g., NR primary cell (PCell) and NR PSCell) is also envisioned.

[0208] A standalone deployment of a first RAT (e.g., NR) can be single or multi-carrier (e.g., NR carrier aggregation, CA, or dual connectivity with an NR PCell and an NR PSCell). A non-standalone (NSA) deployment of a first RAT (e.g., NR) refers to a dual connectivity (DC) deployment including a second RAT (e.g., E-UTRA), for example, when there is a Long Term Evolution (LTE) PCell and an NR PSCell (which may be one or more LTE SCells and one or more NR SCells). The LTE PCell and NR PSCell are configured in a master cell group (MCG) and a secondary cell group (SCG), respectively. The MSG and SCG are more commonly referred to as cell groups (CGs). The MCG and SCG may be configured with one or more additional serving cells, for example, one or more LTE secondary cells (SCells) in the MCG and one or more SCells in the SCG.

[0209] Carrier aggregation (CA) is commonly used in RATs (e.g., NR and LTE systems) to improve the transmission and reception data rates of communication devices. In CA, a UE typically initially operates on a single serving cell, called a primary cell (Pcell). The Pcell operates on a component carrier of a frequency band. The UE is then configured by the network with one or more secondary serving cells (Scells). Each Scell ​​can correspond to a component carrier (CC) in the same frequency band (intra-band CA) or a different frequency band (inter-band CA) than the frequency band of the CC corresponding to the Pcell. For the UE to transmit and receive data on the Scell, the Scell ​​may need to be activated by the network (e.g., by receiving downlink shared channel (DL-SCH) information on a physical downlink shared channel (PDSCH) or by transmitting uplink shared channel (UL-SCH) information on a physical uplink shared channel (PUSCH). The Scell ​​can also be deactivated and later reactivated as needed via activation / deactivation signaling. A UE may be configured with carrier aggregation to aggregate frequency division duplexed (FDD) carriers, time division duplexed (TDD) carriers, or both FDD and TDD carriers. A UE may indicate its carrier aggregation capabilities via capabilities, including whether it supports CA on the downlink and whether it supports CA on the uplink.

[0210] A wireless system may incorporate multiple uplink enhancement technologies. For example, 3GPP 5G NR Rel. 15 includes three multiple uplink enhancement technologies: EUTRA-NR Dual Connectivity (EN-DC), Uplink Carrier Aggregation (CA), and Supplemental Uplink (SUL).

[0211] The above mechanisms are designed to address the issue of NR coverage enhancement. In all of the above scenarios, a UE may be configured with a first carrier (e.g., an LTE carrier and / or a SUL carrier) in a lower frequency band (e.g., an FDD band) and a second carrier (e.g., an NR carrier and / or a NUL carrier) in a higher frequency band (e.g., a TDD band). The lower frequency band carrier may have a larger coverage area. The higher frequency carrier may have a smaller coverage area. The UE can transmit data either under the first carrier coverage (i.e., the lower frequency band carrier with larger coverage) or under both the first carrier and the second carrier coverage (i.e., the higher frequency band carrier with smaller coverage). This solves the problem of user coverage at the edge of the cell.

[0212] Commercial UEs, limited by antenna design complexity and low transmit power, typically support two transmit channels (2Tx). In the above uplink enhancement scenario, one Tx of the UE transmitter may be used for a first carrier (e.g., an LTE carrier, and / or a first NR carrier, and / or a SUL carrier), and the other Tx of the UE transmitter may be used for a second carrier (e.g., a 5G NR carrier, and / or a second NR carrier, and / or a NUL carrier).

[0213] Figure 17A shows an example application scenario for EN-DC deployment. The diagram illustrates the difference between 4G and 5G coverage. In Area A, both 4G and 5G coverage exist, so an EN-DC-capable UE may transmit data via the 4G and / or 5G network. Commercially available terminals generally support two transmission channels (2Tx), so one Tx may be used for 4G and the other for 5G NR. In Area B, there is 4G coverage, so the UE may transmit data via the 4G network, e.g., rather than via the 5G network.

[0214] Figure 17B shows an example of an uplink operation mode of a UE in Area A and Area B according to Figure 17A. A mobile device supporting EN-DC has two simultaneous radio connections to the Evolved Packet Core (EPC), one via 5G NR and the other via LTE. However, because the UE uses one Tx for 5G NR, the uplink dual-stream capability of 5G NR is limited, meaning that the peak uplink data throughput is, for example, 74% of that achievable with 5G SA. In general, in a non-standalone (NSA) architecture, 5G uplink throughput is improved compared to 4G but still lower than 5G standalone (SA). While 5G NR coverage is not improved, in areas without 5G coverage where both signaling and traffic can be transmitted via 4G, the user experience is not significantly worse than with 4G network coverage.

[0215] Figure 18A illustrates an example application scenario for UL inter-band CA. In area A, which has coverage of NR carrier 1 and NR carrier 2, UL CA can be activated. In area B, with coverage of one carrier, a UE transmits data using one carrier. Inter-band carrier aggregation aggregates carriers from different operating bands. For example, 3GPP may be compatible with 13 inter-band CA operating bands involving FR1, such as CA_n3-n78 and CA_n28-n78. In areas with good coverage of two aggregated carriers, uplink CA can be used to improve spectrum utilization. However, because most mobile devices support two transmission channels (2Tx), each of which supports two carriers, UL CA may limit uplink dual-stream performance over TDD-NR, resulting in capacity loss.

[0216] Figure 18B shows an example of an uplink operation mode for a UE in Area A and Area B according to Figure 18A. FDD-NR typically employs mid-range or low-range bands, which provide better uplink coverage than TDD-NR. Therefore, FDD-NR can be used to provide 5G services beyond the TDD-NR coverage area to improve user experience. For example, if the uplink data rate at the cell edge is 2 Mbps, aggregation of FDD-NR 2.1 GHz (20 MHz bandwidth) and TDD-NR 3.5 GHz (100 MHz bandwidth) can improve coverage by 17.8% compared to SA-based TDD-NR single carrier. UL inter-band CA can negatively impact capacity because it does not allow for uplink dual-streaming. For example, when 2.1 GHz (20 MHz bandwidth) and 3.5 GHz (100 MHz bandwidth) are aggregated, the uplink peak data rate of a single user is reduced to 80% of the uplink peak data rate with 3.5 GHz in SA mode. In this case, to maximize resource utilization, the gNB does not activate uplink CA but instead activates single-carrier mode. It can be clarified that UL CA does not negatively impact capacity in all scenarios. The single-user uplink throughput of CA is directly related to the bandwidth and uplink duty cycle (of the TDD-NR carrier) of the two aggregated component carriers (CC1 and CC2). For example, CC1 is a TDD-NR carrier (50 MHz bandwidth and 2.5 ms dual-period frame structure) and CC2 is an FDD-NR carrier (20 MHz bandwidth). The uplink peak throughput of UL CA increases by approximately 8% compared to the uplink peak throughput of a dual-stream TDD-NR single carrier. CA technology has been introduced since the 4G era and has been successfully deployed and commercialized worldwide. NR CA has been included in 3GPP Rel-15 and later. Intra-band CA aggregates multiple frequency carriers in the same band to improve user experience.However, the throughput of inter-band CA may in some cases be limited by the number of transmission channels of a terminal.

[0217] Figure 19A shows an example of supplemental uplink coverage. A supplemental uplink (SUL) is introduced to extend uplink coverage by providing a supplemental uplink (typically in the sub-3 GHz band). In the SUL, a DL frequency band (NR frequency band) and two uplink frequency bands (one NR frequency band and one SUL frequency band) are configured in the same cell. When the uplink coverage of the NR carrier is good, the UE transmits and receives data using the NR carrier. When the UE is moving beyond the uplink coverage of the NR carrier, the UE transmits data using the SUL carrier. The UE can dynamically select either the UL NR or SUL for data transmission, but the two carriers cannot be used simultaneously. The uplink operating band of the SUL is defined similarly to the uplink operating band of the corresponding FDD-LTE / FDD-NR operating band and must be shared with the existing network (4G or 5G). The SUL band cannot be used alone because it may include the uplink. For example, 3GPP is compatible with eight combinations of SUL and NR bands, including the n78, n79, and SUL band combination definitions.

[0218] Figure 19B shows an example application scenario for SUL: In area A, with good TDD-NR coverage, the UE uses TDD-NR for data transmission. In area B, beyond the TDD-NR uplink coverage, the UE switches to the SUL band for data transmission.

[0219] Figure 19C shows an example of an uplink operation mode for a UE in Area A and Area B according to Figure 19B. SUL may be implemented in sub-3 GHz bands, which have better uplink coverage than TDD-NR bands, thus improving the user experience. For example, in a dense urban area where the cell-edge uplink data rate is 2 Mbps, if SUL 2.1 GHz (20 MHz bandwidth) and TDD-NR 3.5 GHz (100 MHz bandwidth) are deployed for networking, network coverage can increase by 17.8% compared to that of a TDD-NR single-carrier and SA architecture. In TDD-NR coverage areas, SUL does not affect the peak throughput of a single user because TDD-NR is used for data transmission and reception. The disadvantage of SUL is that the common 5G NR band and SUL band must be in the same cell, limiting its applicability, making them more interdependent. SUL technology improves uplink coverage by using sub-3 GHz bands for uplink transmission. SUL defines a new paired spectrum between TDD-NR and SUL, and SUL is obtained by sharing spectrum with 4G networks. Therefore, 5G may be co-sited with 4G, which limits the flexibility of 5G deployment and brings new challenges to network deployment.

[0220] As seen in the UL scenario above, commercially available UEs using a single Tx for 5G NR cannot utilize the uplink dual-stream capabilities of 5G NR, resulting in peak UL data throughput that is much lower than the achievable throughput. 3GPP Rel. 16 introduced UL Tx switching as a new feature to enhance EN-DC, UL CA, and SUL performance. UL Tx switching can maximize uplink resource utilization in relation to UE capabilities. It uses one Tx channel for either Carrier 1 or Carrier 2, and the other Tx channel only for Carrier 2.

[0221] A transmitter (Tx) of a wireless device may have / include one or more (e.g., two) antennas / Tx chains. Throughout this disclosure, the terms “antenna” and / or “Tx chain” may be used interchangeably and / or to refer to a physical antenna connector (e.g., a respective antenna unit) of a UE that can integrate hardware and software to transmit / radiate / propagate wireless signals into the air oriented as a specific beam. Here, an antenna may include an array / group of multiple antenna elements that generate signals based on beamforming and / or MIMO / mass MIMO. Throughout this disclosure, the following terms may be used interchangeably: Tx, antenna, transmit antenna, transmitter antenna, transmission antenna, Tx antenna, transmit channel, Tx channel, transmission channel, transmit chain, Tx chain, Tx RF chain, transmit chain, physical antenna port. In some embodiments, “Tx” may be used in shorthand to refer to the above concepts.

[0222] The antenna may include one or more RF components and / or an antenna array configured to transmit and / or receive wireless signals. The antenna may be coupled to a radio front-end circuit and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In some embodiments, the antenna may include one or more omnidirectional sector or panel antennas operable to transmit / receive wireless signals, for example, between 2 GHz and 66 GHz. An omnidirectional antenna may be used to transmit / receive wireless signals in any direction, a sector antenna may be used to transmit / receive wireless signals from devices within a specific area, and a panel antenna may be a line-of-sight antenna used to transmit / receive wireless signals in a relatively straight line. In some instances, the use of two or more antennas may be referred to as MIMO. In certain embodiments, the antenna may be separate from the network node or connectable to the network node via an interface or port. The RF interface may be configured to provide a communication interface to RF components such as a transmitter, receiver, and antenna.

[0223] For example, an advanced antenna system (AAS) is the combination of an AAS radio with a set of AAS features. The AAS radio consists of an antenna array tightly integrated with the hardware and software necessary to transmit and receive radio signals, as well as signal processing algorithms that support the execution of AAS functions. Compared to conventional systems, this solution offers much greater adaptability and steerability in adapting antenna radiation patterns to rapidly changing traffic and multipath radio propagation conditions. Furthermore, multiple signals can be received or transmitted simultaneously with different radiation patterns. Multiple antenna techniques, referred to herein as AAS features, include beamforming and MIMO. Applying AAS features to an AAS radio results in significant performance improvements due to the greater degrees of freedom provided by a larger number of radio chains, also known as massive MIMO.

[0224] For beamforming, a UE can control wavefront direction using multiple antennas by appropriately weighting the magnitude and phase of individual antenna signals within an array of multiple antenna elements. That is, the same signal is transmitted from multiple antennas with sufficient spacing (at least half a wavelength) between them. Thus, at any given location, the receiver receives multiple copies of the same signal. Depending on the receiver's location, the signals may be in opposite phases, destructively averaging each other, or constructively summing when different copies are in the same phase, or anything in between. By adjusting the phase and amplitude of the transmitted signals, constructive addition of the corresponding signals at the base station receiver can be achieved, which increases the received signal strength and therefore the UE's uplink throughput. The more antenna elements there are, the higher the gain.

[0225] In digital beamforming (also known as baseband beamforming or precoding), signals are pre-coded (amplitude and phase correction) in baseband processing before RF transmission. Multiple beams (one per user) can be formed simultaneously from the same set of antenna elements. In analog beamforming, the signal phase of the individual antenna signals is adjusted in the RF domain. Analog beamforming affects the radiation pattern and gain of the antenna array, thus improving coverage. Unlike digital beamforming, one beam can be formed per set of antenna elements.

[0226] Spatial multiplexing, referred to here as MIMO, is the ability to transmit multiple data streams, called layers, using the same time and frequency resources, with each data stream potentially beamformed. The goal of MIMO is to increase throughput. MIMO is built on the fundamental principle that, when the received signal quality is high, it is better to receive multiple data streams with reduced power per stream than a single stream at full power. When the received signal quality is high and the streams do not interfere with each other, the potential is large. When mutual interference between streams increases, the potential decreases. The number of layers / data streams that can be supported can be referred to as a "rank." To distinguish between UL layers, a UE must have at least as many Tx antennas as layers, e.g., two Tx antennas to support two-layer (or two-port) transmission.

[0227] An antenna port may generally be used as a general term for signal transmission under identical channel conditions. A separate logical antenna port may be defined for each operating mode (e.g., SISO vs. MIMO) where independent channels are assumed. Signals transmitted from different antenna ports may experience different "wireless channels" even when a set of antennas is located at the same site. In some cases, it is important for transmissions to share the same antenna port (e.g., quasi-colocated). OFDM symbols transmitted over the same antenna port are subject to identical channel conditions. This helps a base station estimate the channel using a reference signal (e.g., DMRS) and use that information in decoding information content on a physical channel (e.g., PUSCH / PUCCH). According to the definition in the 3GPP® specification, an antenna port is defined so that the channel on which a symbol on an antenna port is carried can be inferred from the channel on which another symbol on the same antenna port is carried. MIMO exploits this property (different wireless channels) across different antenna ports to transmit multiple parallel data streams. It is important to understand that an antenna port is an abstract concept. There is a difference between a logical antenna port and a physical antenna element. A particular transmission uses particular antenna ports, which are then mapped onto one or more physical antenna elements.

[0228] Figure 20 illustrates an example of a wireless device transmitter antenna. Logical antenna ports are mapped to physical antenna ports as shown in the figure. The mapping of antenna ports to physical antennas is controlled by specific beamforming, as signals must be transmitted on specific antenna ports to form the desired beam. Two antenna ports may be mapped to one physical antenna port, and / or a single mapped antenna port may be mapped to multiple physical antenna ports.

[0229] To determine the characteristic channel of an antenna port, the UE may perform a separate channel estimation for each antenna port. A separate reference signal suitable for estimating the respective channel may be defined for each antenna port. How these logical antenna ports are assigned to the UE's physical transmit antennas may be up to the UE and may vary between UEs of the same type (due to different operating conditions) and between UEs from different manufacturers. The UE may not explicitly notify the base station of the mapping performed; rather, the base station may automatically take this into account during demodulation.

[0230] For UL channel estimation, it depends on whether time division duplexing (TDD) or frequency division duplexing (FDD) is used. For TDD, the same frequency is used for both UL and DL transmission. Because the radio channel is reciprocal (same for UL and DL), detailed short-term channel estimates from UL transmissions of known signals can be used to determine the DL transmit beam. This is called reciprocal-based beamforming. For full channel estimation, signals should be transmitted from each UE antenna and across all frequencies. For FDD, where different frequencies are used for UL and DL, the channel is not fully reciprocal.

[0231] UE transmitter characteristics may be specified at the UE's antenna connector with single or multiple transmit antennas. For UEs with integrated antennas, a reference antenna with 0 dB gain may be assumed. Transmitter requirements for UL MIMO operation may apply when the UE transmits on two ports of the same CDM group. The UE may use a higher MPR (Maximum Power Reduction Allowed) value outside of this limit.

[0232] In the case of inter-band carrier aggregation with one uplink carrier allocated to one NR band, transmitter power requirements may apply. In the case of inter-band carrier aggregation with uplinks allocated to two NR bands, the UE maximum output power should be measured across all component carriers from the different bands. If each band has a separate antenna connector, the maximum output power is measured as the sum of the maximum output power at each UE antenna connector. The measurement period shall be at least one subframe (1 ms).

[0233] For uplink transmission, the UE may reconfigure / retune some radio frequency (RF) hardware (and / or Tx chains, e.g., filters and / or duplexers) between two carriers, e.g., from a first carrier to a second carrier or vice versa. This reconfiguration / retuning may also be referred to as moving / switching Tx chains between carriers. In effect, UL Tx switching between two carriers involves reconfiguring / retuning UL Tx chains / antennas from the center frequency of the first carrier to the center frequency of the second carrier (or vice versa). The same UL Tx chains / antennas / antenna connectors may be used for uplink transmissions via the first carrier (e.g., before switching) and the second carrier (e.g., after switching). UL Tx switching may be in response to receiving a scheduling command and / or a TDD UL symbol / slot / subframe and is therefore also referred to as dynamic UL Tx switching.

[0234] Throughout this disclosure, the following terms may be used interchangeably: Tx switching, UL switching, carrier switching, UL carrier switching, UL Tx switching, UL transmit switching, UL transmit channel switching, UL Tx chain switching, UL Tx antenna switching, Tx antenna switching, dynamic UL Tx switching.

[0235] Figure 21A shows an example of uplink Tx switching for a UE with two Txs. As shown in the figure, UL Tx switching allows for two modes of operation: Mode 1, in which one Tx channel is used for a 2.1 GHz carrier and the other for a 3.5 GHz carrier, and Mode 2, in which one Tx channel is switched to 3.5 GHz and the other remains at 3.5 GHz, allowing for TDD-NR dual-stream transmission. Uplink Tx switching is used when switching between Mode 1 and Mode 2.

[0236] Figure 21B shows example transmission options for UL Tx switching. Because UE capabilities vary from terminal to terminal, Option 1 and Option 2 are further defined in Rel-16, as shown in the figure. In Option 1, the UE can transmit data over Carrier 1 and Carrier 2 in time division mode (TDM), but not simultaneously. This option may be called a "switched uplink." In Option 2, on the terminal side, Carrier 1 and Carrier 2 can be flexibly aggregated in either TDM mode or simultaneous transmission mode. This option may be called a "dual uplink."

[0237] Figure 22A shows an example of a UE uplink operation mode with uplink Tx switching in an EN-DC scenario. In uplink Tx switching (EN-DC), in a TDD-NR uplink time slot, the Tx channel that originally supported LTE is switched to the TDD-NR frequency band, resulting in the UE using dual streams on the uplink, while in other time slots, Tx reverts to LTE. Depending on UE capabilities and radio environment factors, the UE can operate in different modes, as shown in Figure 22A. Uplink Tx switching is used to improve uplink capacity. In uplink Tx switching, in a TDD-NR uplink time slot, dual streams are maintained, while in other time slots, the UE uses the conventional EN-DC mode, resulting in an increase in uplink peak throughput of approximately 17% over that of TDD-NR with SA architecture.

[0238] Figure 22B shows an example of an uplink operation mode of a UE with uplink Tx switching in an inter-band CA scenario. When uplink Tx switching is activated for inter-band CA, in TDD-NR, the UE can transmit data in dual streams in the UL time slot. For example, when close to a cell tower, the UE can use inter-band CA with uplink Tx switching to further improve capacity and reduce latency. At the cell edge, the UE transmits data using the FDD frequency band while maintaining FDD and TDD carrier aggregation in the downlink, improving the user experience. Inter-band CA can flexibly support uplink Tx switching options 1 and 2. The UE functions in one of the modes shown in Figure 22B, depending on the UE capabilities and radio environment. Furthermore, 3GPP Rel-16 expands the frequency band combinations for carrier aggregation to 78. By integrating CA with uplink Tx switching, CA can improve 5G performance in coverage, capacity, and latency.

[0239] Uplink Tx switching allows a UE to simultaneously connect to both FDD and TDD carriers, even at the cell edge, solving the problem of lack of 5G access due to limited uplink capacity. For example, for TDD-NR with 3.5 GHz and 100 MHz bandwidths and the 2.1 GHz FDD-NR frequency band used for carrier aggregation, when the cell edge uplink data rate is 2 Mbps, adopting CA with uplink Tx switching can increase network capacity by 17.8% compared to a network with single-carrier TDD-NR. When a 3.5 GHz (100 MHz bandwidth) TDD-NR aggregates a 2.1 GHz (20 MHz bandwidth) FDD-NR with uplink Tx switching, the uplink peak throughput capacity is improved by 20%. Uplink Tx switching can increase uplink time slot availability to 100%, and therefore the HARQ RTT can be reduced by 25% without uplink data needing to wait for a TDD-NR uplink time slot. 3GPP Rel-15 introduced inter-band CA with simultaneous transmission on two carriers, which could result in capacity loss without dual-stream transmission of TDD-NR on the uplink. With uplink Tx switching, this limitation is eliminated by transmitting data on FDD-NR and TDD-NR carriers in TDM mode. CA with uplink Tx switching maximizes spectrum utilization in both the time and frequency domains and, combined with the power boost feature on TDD-NR carriers, maximizes spectrum utilization to achieve a better user experience.

[0240] Figure 22C shows an example of an uplink operation mode of a UE with uplink Tx switching in an SUL scenario. Uplink Tx switching allows the SUL to integrate both TDD-NR and SUL time-frequency resources into the TDD-NR coverage area, thereby increasing uplink capacity. The SUL supports Option 1 (TDM mode) with uplink Tx switching. Depending on the radio environment, the UE operates in the mode shown in Figure 22C. When close to the cell tower, the UE switches between the TDD-NR and SUL frequency bands for data transmission. At the cell edge, the SUL carrier is used to provide uplink coverage. Therefore, SUL with uplink Tx switching can improve uplink throughput, reduce latency, and improve coverage compared to SUL without uplink Tx switching. Uplink Tx switching allows the SUL's uplink time-frequency resources to be allocated to the UE, increasing single-user uplink capacity by 20%. Up to 100% of the uplink time slots can be available, reducing HARQ RTT by nearly 20%.

[0241] Some LTE-NR aggregation combinations of channels across two bands may be considered difficult to achieve because simultaneous uplink transmissions on these bands, for example, from a base station to a wireless device, result in inter-modulation (IM) products in the downlink (DL) between the bands. For example, this may occur for inter-band frequency division duplexing (FDD)-FDD and time division duplexing (TDD)-TDD combinations. This means that there are channel combinations across the two bands that are not difficult to achieve, meaning that a wireless device may support dual simultaneous uplinks for the band combination. Here, the channels may be a portion of a spectrum.

[0242] For example, for aggregation combinations that result in IM products due to simultaneous multiple uplink (UL) transmissions from a wireless device to a base station, any IM issues depend on the actual output power, power balance, allocation, desired signal level, and other interference of the UL. Different wireless device implementations will have different performance. In an ideal scenario, the BS can reliably obtain channel state information (CSI) reports and PHRs, and then take action on known band combinations if IM can be distinguished from other external interference.

[0243] A UE that supports uplink CA between carriers can be assumed to have a dedicated transmit (Tx) chain for each carrier and can therefore support CA without any restrictions. On the other hand, there may be UEs that may share some hardware (e.g., Tx antennas, power amplifiers, phase-locked loops, transmitter chain circuitry, etc.) across two carriers and therefore require special handling (e.g., via scheduling) to ensure proper operation. For example, a UE may have two Tx chains and can transmit on the uplink on two carriers, but with some restrictions. Because such a UE has two Tx chains, it cannot transmit one Tx on carrier 1 and two Tx on carrier 2 (e.g., to support two-tier multiple-input multiple-output (MIMO) on carrier 2), and therefore the UE can support either Case 1 or Case 2 for transmitting on the uplink.

[0244] A dual UL implementation is certainly possible at a higher cost in terms of additional RF components, e.g., two TX digital front ends, an additional TX phase-locked loop (PLL), an additional TX measurement receiver, power management between the two ULs (in different stacks), a multiplexer filter required after the PA (duplexer replaced by a multiplexer), and isolation between the TX paths.

[0245] A switching gap may be required to allow the UE enough time to switch between two carriers (moving / reconfiguring some hardware (or Tx chains) from carrier 1 to carrier 2 or vice versa). The network (NW) needs to provide a switching gap for one of the carriers and also needs to provide enough additional relief for the UE Physical Uplink Shared Channel (PUSCH) processing time, which is typically the time between the end of the uplink (UL) grant and the start of the PUSCH.

[0246] For example, when configuring a serving cell with an uplink carrier for dual connectivity and / or carrier aggregation, the network may send an inquiry for UE radio access capability information (e.g., UECapabilityEnquiry). If the network needs (additional) UE radio access capability information, it initiates the procedure to the UE in RRC_CONNECTED. The UE may receive the inquiry from the base station, for example, via an RRC message. The UE may configure the content of the capability information (e.g., UECapabilityInformation) message based on the request field of the inquiry message. For example, if the ue-CapabilityRAT-RequestList includes a UE-CapabilityRAT-Request with rat-Type set to nr, the UE shall include a UE-CapabilityRAT-Container of type UE-NR-Capability and rat-Type set to nr in the ue-CapabilityRAT-ContainerList. The UE may include a list of supported band combinations and feature sets (e.g., supportedBandCombinationList, featureSets, and featureSetCombinations).

[0247] The UE may transmit an RRC message including UE capability information. The UE capability information may include a list of band combinations (e.g., BandCombinationList) supported by the UE. The list of band combinations may include a list of NR CA, NR non-CA, and / or MR-DC band combinations (including DL-only or UL-only bands).

[0248] In one embodiment, the inquiry may include a request for UL Tx switching (e.g., uplinkTxSwitchRequest). In response, the UE may transmit a list of band combinations that the UE can support for UL Tx switching (e.g., BandCombination-UplinkTxSwitch). For example, the UE may include in its list of supported band combinations for UL Tx switching (e.g., supportedBandCombinationList-UplinkTxSwitch) as many NR-only / E-UTRA-NR band combinations that support UL Tx switching as possible from the list of candidate band combinations, starting from the first input.

[0249] The list of supported band combination(s) for UL Tx switching may include a list of supported band pairs(s) (e.g., supportedBandPairListNR) and / or a support option for uplink Tx switching (e.g., uplinkTxSwitching-OptionSupport). For example, the support option may indicate a "switched UL" mode (e.g., TDM transmission), or a "dual UL" mode (simultaneous transmission), or both modes. For example, the support option may indicate whether power boosting for UL Tx switching is supported (e.g., uplinkTxSwitching-PowerBoosting).

[0250] Each band pair of the supported band pairs for UL Tx switching includes a first frequency band and a second frequency band. The capability information indicates, for each band pair (e.g., ULTxSwitchingBandPair), the index of the first frequency band (e.g., bandIndexUL1) and the index of the second frequency band (e.g., bandIndexUL2) for simultaneous transmission. The capability information may also indicate, for each band pair, a switching gap / period associated with the two frequency bands of the band pair (e.g., uplinkTxSwitchingPeriod). For example, the switching gap / period may be a duration of microseconds (e.g., 35 us, 140 us, or 210 us).

[0251] The network can configure one or more cells for the UE. For example, the network may send an RRC message indicating one or more cell groups (e.g., CellGroupConfig). The RRC message may include configuration parameters for one or more serving cells, e.g., Pcell and / or SPcell and / or Scell, for the cell group (MCG and / or SCG). Each of the one or more serving cells may include one or more uplink carriers (e.g., UL (NUL) and / or SUL). The RRC message may include a parameter indicating an option, e.g., switched UL or dual UL, for UL Tx switching within the cell group (e.g., uplinkTxSwitchingOption), based on, e.g., UE capability information. The RRC message may include a parameter indicating whether power boosting is enabled for UL Tx switching within the cell group (e.g., uplinkTxSwitchingPowerBoosting).

[0252] The network may configure one or more serving cells for the UE, which may be an SpCell or SCell of an MCG or SCG. The UE may receive one or more RRC messages including configuration parameters of the one or more serving cells. The configuration parameters of the serving cell may indicate a downlink configuration and / or an uplink configuration. For example, the configuration parameters of the serving cell may indicate one or more downlink BWPs of the serving cell. For example, the configuration parameters of the serving cell may indicate at least one uplink carrier of the serving cell, e.g., UL (NUL) and / or SUL. In the case of an uplink carrier, the configuration parameters may indicate one or more UL BWPs. In the case of an uplink carrier, the configuration parameters may indicate that UL Tx switching is configured (e.g., uplinkTxSwitching).

[0253] The UL Tx switching configuration associated with a cell's uplink carrier may indicate whether the configured uplink carrier is "carrier 1" or "carrier 2" for dynamic UL Tx switching (e.g., via uplinkTxSwitchingCarrier). For example, UL "carrier 1" could be one transmit antenna connector, and UL "carrier 2" could be two transmit antenna connectors. For example, in the case of inter-band UL CA or SUL, the network configures one of the two uplink carriers involved in dynamic UL TX switching as carrier 1 and the other as carrier 2. In the case of (NG)EN-DC, the network always configures the NR carrier as carrier 2.

[0254] The UL Tx switching configuration associated with a cell's uplink carriers may indicate the location of the UL Tx switching period (e.g., via uplinkTxSwitchingPeriodLocation). For example, a Boolean parameter / field may indicate whether the location of the UL Tx switching period is configured on this respective UL carrier. In the case of inter-band UL CA or SUL, the network configures this field for one of the uplink carriers involved in dynamic UL TX switching and configures this field to FALSE on the other carriers. In the case of (NG)EN-DC, the network always configures this field for an NR carrier (i.e., in the case of (NG)EN-DC, the UL switching period always occurs on an NR carrier).

[0255] 23A and 23B show examples of UL Tx switching period positions. A time mask for switching between two uplink carriers is shown in FIG. 23A and 23B. The switching time mask may be applicable to an uplink band pair. For example, the uplink band pair may be associated with an inter-band UL CA configuration and / or SUL configuration and / or dual connectivity (e.g., NR-DC and / or EN / DC and / or NE-DC and / or MR-DC). The two uplink carriers may be in different bands with different carrier frequencies. The UL Tx switching period / gap (e.g., uplinkTxSwitchingPeriod, N TX1-TX2Capability information indicating the power boosting capability (IEpowerboostingTxSwitching) may be present for each band combination associated with two uplink carriers and / or transmitted to the network. For example, when the capability uplinkTxSwitchingPowerBoosting is present and IEpowerboostingTxSwitching is set to 1, NR UL Carrier 1 may be one transmit antenna connector and NR UL Carrier 2 may be two transmit antenna connectors, with a 3 dB boost above maximum output power. The UE may support switching between single-tier transmission with one antenna port and two-tier transmission with two antenna ports on the two uplink carriers according to scheduling commands and / or rank adaptation. In one embodiment, both single-tier and two-tier transmission with two antenna ports, and single-tier transmission with one antenna port, may be supported on NR UL Carrier 2.

[0256] The switching period shown in Figures 23A and 23B is located on either NR carrier 1 or carrier 2, as indicated in RRC signaling (e.g., uplinkTxSwitchingPeriodLocation). Figure 23A shows an example time mask for switching between UL carrier 1 and UL carrier 2, with the switching period located within carrier 1. Figure 23B shows an example time mask for switching between UL carrier 1 and UL carrier 2, with the switching period located within carrier 2. The length of the uplink switching period may be less than the value indicated by the UE capability uplinkTxSwitchingPeriod. The requirement may apply in the case of a co-located and synchronous network deployment for two uplink carriers. The requirement may apply in the case of a single TAG for two uplink carriers, e.g., the same uplink timing for the two carriers.

[0257] The UE may initiate an uplink switching gap N if one or more conditions are met and / or if the UE is configured for UL Tx switching (uplinkTxSwitching). TX1-TX2 Uplink transmissions may be omitted during the switching gap / period N TX1-TX2 is indicated by the UE capability uplinkTxSwitchingPeriod for each band combination associated with two uplink carriers. The UE may indicate its uplink switching capability using a parameter for the band combination (e.g., BandCombination-UplinkTxSwitch). For that band combination, the UE may be configured with an MCG using E-UTRA radio access and an SCG using NR radio access (EN-DC). For that band combination, the UE may be configured with uplink carrier aggregation. For that band combination, the UE may be configured with a serving cell having two uplink carriers with an upper layer parameter of supplementaryUplink (SUL). One or more conditions may exist for the switching gap / period, and the location of the switching gap may be defined as follows:

[0258] T0-T offset If uplink switching is triggered for an uplink transmission starting at T0 after T0, the UE may cancel the uplink switching and / or offset It may not be expected to trigger any other new uplink switching to occur before T0 for any other uplink transmissions scheduled after T offset is the UE procedure time defined for the uplink transmission that triggers the switch.

[0259] The UE is μ UL =max(μ UL,1, μ UL,2 ), and μ UL,1corresponds to the subcarrier spacing of the active UL BWP of one uplink carrier before the switching gap, and μ UL,2 corresponds to the subcarrier spacing of the active UL BWP of the other uplink carrier after the switching gap.

[0260] The UE may indicate uplink switching capability for a band combination (e.g., with BandCombination-UplinkTxSwitch). For that band combination, the UE may be configured with an MCG using E-UTRA radio access and an SCG using NR radio access (EN-DC). The UE may be configured with uplink switching (e.g., with the parameter uplinkTxSwitching).

[0261] The UE may be configured in switched UL transmission mode (e.g., uplinkTxSwitchingOption set to "switchedUL"). offset The UE may transmit on the uplink based on previously received DCI or based on higher layer configuration. The UE may transmit an NR uplink that follows an E-UTRA uplink on another uplink carrier. The UE may transmit an NR uplink that follows an E-UTRA uplink on another uplink carrier during a switching period / gap N of either of the two carriers. TX1-TX2 The UE may not be expected to transmit for the duration of the switching period / gap N of either of the two carriers. The UE may transmit an E-UTRA uplink that follows an NR uplink on another uplink carrier. TX1-TX2 A UE may not be expected to transmit for the duration of the NR uplink. A UE may not be expected to transmit simultaneously on the NR uplink and E-UTRA uplink. If a UE is scheduled or configured to transmit any NR uplink transmission that overlaps with an E-UTRA uplink transmission, the NR uplink transmission may be dropped.

[0262] The UE may be configured in dual UL transmission mode (e.g., uplinkTxSwitchingOption set to "dualUL"). offset The UE may transmit on the uplink based on previously received DCI or based on higher layer configuration. The UE may transmit an NR2 port uplink that follows an E-UTRA uplink on another uplink carrier. The UE may transmit an NR2 port uplink that follows an E-UTRA uplink on another uplink carrier. The UE may transmit an NR2 port uplink that follows an E-UTRA uplink on another uplink carrier during a switching period / gap N of either of the two carriers. TX1-TX2 The UE may not be expected to transmit for the duration of the NR2 port uplink on another uplink carrier. The UE may transmit an E-UTRA uplink that occurs after the NR2 port uplink on another uplink carrier. The UE may not be expected to transmit for the duration of the switching period / gap N TX1-TX2 The UE may not be expected to transmit for a duration of tdm-PatternConfig. The UE may not be expected to transmit two-port transmissions on the NR uplink and E-UTRA uplink simultaneously. In other cases, the UE may be expected to normally transmit all uplink transmissions without interruption. The UE may be configured with tdm-PatternConfig or tdm-PatternConfig2. For E-UTRA subframes designated as uplink by the configuration, the UE may assume an operating state in which it can transmit a one-port E-UTRA uplink. For E-UTRA subframes other than those designated as uplink by the configuration (e.g., downlink and / or special and / or flexible subframes / slots / symbols), the UE may assume an operating state in which it can transmit a two-port NR uplink.

[0263] The UE may indicate uplink switching capability for a band combination (e.g., with BandCombination-UplinkTxSwitch). For that band combination, the UE may be configured with uplink carrier aggregation. The UE may be configured with uplink switching (e.g., with the parameter uplinkTxSwitching). The UE may indicate uplink switching capability for a band combination (e.g., with the parameter uplinkTxSwitching). offsetThe UE may transmit on the uplink based on previously received DCI or based on higher layer configuration. The UE may transmit a two-port transmission on one uplink carrier, and the preceding uplink transmission may be a one-port transmission on another uplink carrier. The UE may transmit a switching period / gap N of either of the two carriers. TX1-TX2 The UE may not be expected to transmit for the duration of N. The UE may be transmitting a one-port transmission on one uplink carrier, and the preceding uplink transmission may be a two-port transmission on another uplink carrier. The UE may be expected to transmit for the duration of N. TX1-TX2 It cannot be expected to transmit for the duration of

[0264] For a UE configured in switched UL transmission mode (e.g., uplinkTxSwitchingOption set to "switchedUL"), when the UE sends a single-port transmission on one uplink carrier, and the previous uplink transmission was a single-port transmission on another uplink carrier, then the UE shall perform a switching period / gap N on either of the two carriers. TX1-TX2 For a UE configured in dual UL transmission mode (e.g., uplinkTxSwitchingOption is set to "dualUL"), when the UE transmits a two-port transmission on one uplink carrier, and the previous uplink transmission was a one-port transmission on the same uplink carrier, and / or the UE is in an operating state in which two-port transmission cannot be supported on the same uplink carrier, then the UE shall not be expected to transmit during the switching period / gap N on either of the two carriers. TX1-TX2For a UE configured in dual UL transmission mode (e.g., uplinkTxSwitchingOption is set to "dualUL"), when the UE transmits a single-port transmission on one uplink carrier, and the previous uplink transmission was a single-port transmission on another uplink carrier, and / or the UE is in an operating state where two-port transmission can be supported on the same uplink carrier, the UE shall not be expected to transmit during the switching period / gap N on either of the two carriers. TX1-TX2 The UE may not be expected to transmit during the period. The UE may not be expected to be scheduled and / or configured with uplink transmissions that result in simultaneous transmission on two antenna ports on one uplink carrier and any transmission on another uplink carrier. In other cases, the UE may be expected to normally transmit all uplink transmissions without interruption.

[0265] The UE may indicate uplink switching capability for a band combination (e.g., with BandCombination-UplinkTxSwitch). For that band combination, the UE may be configured with a serving cell having two uplink carriers, e.g., configured with an SUL with the higher layer parameter supplementaryUplink. The UE may be configured with uplink switching (e.g., with the parameter uplinkTxSwitching). The UE may indicate uplink switching capability for a band combination (e.g., with BandCombination-UplinkTxSwitch). For that band combination, the UE may be configured with a serving cell having two uplink carriers, e.g., configured with an SUL with the higher layer parameter supplementaryUplink. offset If the UE transmits any uplink channel or signal on a different uplink than the preceding transmission opportunity based on DCI received before switching gap N or based on higher layer configuration, then the UE shall determine whether uplink switching occurs within the switching gap N. TX1-TX2 where T0 is the start time of the first symbol of the transmission opportunity for the uplink channel or signal, and T offset is the preparation time for the transmission opportunity of the uplink channel or signal. Switching gap N TX1-TX2During this time, the UE may not be expected to transmit on either of the two uplinks. In other cases, the UE may be expected to normally transmit all uplink transmissions without interruption.

[0266] There are various emerging new consumer services that require high uplink data rates, such as HD video calls, online webcasts / sales, and augmented reality (AR), which require BMS uplink data rates of approximately 10 seconds. To increase uplink throughput and capacity for such widely applicable scenarios, it is necessary to efficiently utilize all uplink resources in multi-carrier scenarios (>2 frequency bands). In practical deployment scenarios, networks support more than two bands. Therefore, efficient utilization of these UL resources can be prioritized.

[0267] However, implementing more than two Txs in a smartphone is difficult due to increased cost, complexity, heat generation, power consumption, and intermodulation interference. Current commercially available smartphones support a maximum of two Tx RF chains, meaning they cannot transmit simultaneously on more than two bands. Implementing more Tx RF chains in a smartphone is difficult for the following reasons: Cost and complexity increase due to the need for more Tx RF chains, power modules, etc. When more than two power modules function simultaneously, size, heat generation, and power consumption also increase dramatically. More Tx RF chains also increase the number of PLLs (phase-locked loops) and LOs (local oscillators), which causes intermodulation interference and degrades downlink performance for some band combinations. Furthermore, some Tx RF resources cannot be fully utilized due to power limitations or the limited availability of UL slots on TDD bands. A high proportion of smartphones is expected in the future. This makes it very difficult for networks to fully utilize all available uplink resources / bandwidths and for smartphones to increase their uplink data rates.

[0268] Extensions for operation with more than four Tx antennas can be considered to target devices such as CPE or IoT devices without size and cost constraints. Extensions for frequency-selective precoding can be considered to provide most gains when transmission involves four MIMO layers, so such gains do not apply to 2-Tx smartphones. mTRP (multiple transmit receive point) uplink enhancements are in principle applicable to all device types and primarily provide gains for cell-edge performance in macrocell mTRP deployments, although uplink performance can be improved for smartphones that are not in coverage-limited conditions.

[0269] Many operators have deployed or are planning to deploy NR on more than two frequency bands with different bandwidths, TDD / FDD duplexing, and DL / UL configurations. To increase uplink throughput and capacity for widely applicable scenarios, it is necessary to efficiently utilize all uplink resources in multi-carrier scenarios (>2 bands) where most devices are smartphones with a limited number of Tx antennas (e.g., 2 Tx). Therefore, it is important to dynamically enable 2 Tx switching between more than two UL bands.

[0270] In existing technologies, band configuration and UL capabilities for simultaneous transmission are strictly coupled. Limited by protocol design, a 2Tx UE can be configured with two UL bands, and thus 2Tx switching can be performed across the two configured UL bands. Semi-static RRC cell reconfiguration can be used to select / switch carriers among more than two bands. Introducing UL Tx switching between two configured bands for a 2Tx UE improves UL data rates by enabling 2Tx to be used for UL MIMO on either one of the two bands in a switching manner. For the uplink, the network must configure the serving cell to comply with the UE uplink capabilities derived from the FeatureSetCombination requirements, regardless of the serving cell's state, e.g., whether activated or deactivated. In other words, UE uplink capabilities, such as band configuration, activation, and simultaneous transmission, are strictly coupled in existing technologies. For example, the maximum number of configured bands, the maximum number of activated bands, and the maximum number of PUSCH uplink transmission bands are equal to each other. The maximum number of PUSCH transmission bands depends on the number of simultaneous Tx RF chains equipped on the UE. Thus, limited by protocol design, a 2Tx UE can simultaneously configure up to two UL bands with or without Tx switching, which can enable activation / deactivation on the two configured UL bands. A 2Tx UE can select or switch carriers among more than two UL bands by RRC-based cell reconfiguration, which requires much longer latency.

[0271] In existing technology, switching carriers between two or more UL bands is via RRC-based cell reconfiguration, which requires long delays, e.g., about 50 ms (Note: fast cell startup / shutdown is possible within the two configured UL bands). Dynamic UL 2Tx switching between two or more UL bands can enable much faster carrier switching, requiring much shorter delays, e.g., symbol-level delays similar to SRS carrier switching.

[0272] It is desirable to separate the band configuration and the UL capability of simultaneous transmission, e.g., maximum number of configured bands > maximum number of simultaneous transmission bands. This allows a UE with 2 Tx to be configured with more than two UL bands and therefore dynamically perform Tx switching across more than two configured UL bands, e.g., four UL bands. This allows for flexible spectrum access.

[0273] Dynamic 2Tx switching between more than two bands may be based on the traffic in each band, the TDD D / U (downlink symbols / uplink symbols) configuration, bandwidth, and channel conditions. Dynamic 2Tx switching between more than two bands may result in higher UL data rates, higher system spectrum utilization, and higher UL capacity for delay-coupled traffic due to efficient utilization of TDD UL slots, better adaptation to channel conditions, and higher trunk efficiency.

[0274] To compare the RF complexity of 2 Tx switching on more than two UL bands, the Tx switching requires several switches, but the comparison can be made with 3 Tx or 4 Tx devices, i.e., devices that support 3 UL or 4 UL simultaneous transmissions. The RF of these devices is much more complex than 2 Tx with Tx switching. The main difference is the number of power supplies and Tx RF chains required (only 2 power supplies and 2 Tx RF chains are required for simultaneous uplinks).

[0275] In 5G Evolution (Release 18), flexible spectrum access (FSA) as a flexible spectrum utilization mechanism for dual-Tx or triple-Tx UEs is an important direction for improving uplink user-perceived throughput and network throughput. For example, UE capabilities for configuration, activation, and simultaneous transmission can be decoupled. In this way, a UE can be configured and activated in more than two bands while utilizing one or two of those bands for simultaneous PUSCH transmission with two simultaneous Tx RF chains. Therefore, FSA provides a mechanism for dynamically selecting a subset of configured carriers and switching Txes accordingly for transmission based on the traffic, TDD D / U configuration, bandwidth, and channel conditions in each band. Furthermore, a UE device capable of dual-Tx switching between more than two UL bands is much less complex and costly than a UE device capable of simultaneous transmission in more than two UL bands (e.g., a triple-Tx or triple-Tx UE), the main difference stemming from the number of power sources.

[0276] By supporting dynamic UL Tx switching between more than two bands, FSA can result in higher UL data rates, higher system spectrum utilization, and higher UL capacity for delay-combined traffic.

[0277] Dynamic UL Tx switching between more than two bands enables efficient utilization of TDD UL slots. The network can dynamically schedule a UE on a band with a wider bandwidth and / or the most unscheduled RBs in a given slot. For example, for a given slot, when one of the active TDD bands / cells is downlink (D), the UE can be switched to another TDD band that is uplink (U) according to the TDD configuration, which can provide a higher UL data rate with a wider bandwidth, and when uplink slots are available on the band, the UE can be switched to the TDD band. As a result, FSA can achieve a higher UL data rate due to more UL available resources.

[0278] Dynamic UL Tx switching between more than two bands allows for better adaptation to channel conditions. The network can schedule UEs on bands with better channel conditions. Compared to legacy mechanisms, more UL bands are available for improved channel adaptation. For example, for cell-edge users, selecting the best UL carrier and RB from the more UL spectrum enabled by FSA results in better uplink coverage and higher UL system efficiency.

[0279] Dynamic UL Tx switching between two or more bands enables higher trunk efficiency. Emerging applications such as virtual reality and augmented reality impose strict latency (millisecond-level) and reliability requirements. FSA can mitigate transmission timeout issues and thus provide significant performance improvements for these applications thanks to TTI-level carrier switching and fast system load balancing. Specifically, considering that traffic arrives randomly, when a frequency band is congested with user traffic, FSA can dynamically allocate part of the traffic load to another frequency band, allowing unoccupied resources to be used as much as possible.

[0280] In existing technologies, a UE may be semi-statically configured with two carriers from two frequency bands for UL Tx switching. For example, the UE may receive higher layer signaling (e.g., an RRC message) semi-statically configuring two carriers with two frequency bands for UL Tx switching. For example, the higher layer signaling, configuring two carriers with two frequency bands for UL Tx switching, may require a long time (e.g., tens of milliseconds). To enable dynamic UL Tx switching across M (e.g., M>2) frequency bands, the UE supports M Tx antennas / chains (which incurs high cost and high power consumption). To enable dynamic UL Tx switching across M (e.g., M>2) frequency bands, for example, lower layer signaling (PDCCH (e.g., DCI) in the PHY layer and / or MAC CE in the MAC layer) mechanisms can be incorporated into UL Tx switching to help a 2Tx UE dynamically use one or more UL carriers with one or more bands switched among multiple bands (e.g., M bands). Based on existing technology, there are gaps to enable this functionality for 2Tx UEs, for example, existing UL Tx switching technology is not scalable to support more than two frequency bands.

[0281] For example, if switching between any two bands out of M (M>2) constituent bands is allowed, new Tx switching scenarios (e.g., Tx switching and / or switching of any of two Txs between the same two bands) may emerge that are not supported by current standards and / or technologies. Some of these new Tx switching scenarios may not be necessary and / or may not be essential for UL capacity increase in practical deployments.

[0282] Figure 24 shows an example of UL Tx switching for a 2-Tx UE. As shown in the figure, based on existing technology, a UE may be configured with carrier 1 in band 1 and carrier 2 in band 2, e.g., carrier 1 may be one Tx antenna and carrier 2 may be two Tx antennas. The UE may use a first Tx (e.g., Tx-1 in the figure) for uplink transmission over carrier 2 and, based on UL Tx switching, use a second Tx (e.g., Tx-2 in the figure) for uplink transmission over carrier 1 and carrier 2. If the UE is configured with more than two bands, e.g., carrier 3 in band 3 and / or carrier 4 in band 4, then different possibilities may arise depending on whether carrier 3 and carrier 4 are configured to support dual-stream UL transmission (e.g., they may be one Tx antenna or two Tx antennas).

[0283] Figure 25 shows an example of UL Tx switching for a 2-Tx UE across more than two bands. In this example, carrier 1 and carrier 3 are configured to allow one Tx antenna (e.g., supporting single-tier transmission), and carrier 2 and carrier 4 are configured to allow two Tx antennas (e.g., supporting single-tier and dual-tier transmission). As shown in the figure, if no restrictions apply, the UE can switch (move / retune / reconfigure) the Tx chains / antennas for any and / or both of the M=4 bands. For example, at time T2, a grant for carrier 2 is received, which requires the UE to switch both Tx-1 and Tx-2 from band 4 to band 2. This is a new Tx switching scenario. For example, at time T3, a first grant is received for carrier 3 and a second grant is received for carrier 4, which requires the UE to switch both Tx chains (Tx-1 from band 2 to band 3 and Tx-2 from band 2 to band 4). In another example, the UE may switch Tx-2 from Band 2 to Band 3 and Tx-1 from Band 2 to Band 4. Depending on which Tx switches from which band to which band, the resulting switching gap, and therefore the uplink transmission, may be different. A similar scenario occurs at T4. For example, at time T5, a grant is received for carrier 4, which requires the UE to switch both Tx chains (Tx-1 from Band 1 to Band 4 and Tx-2 from Band 2 to Band 4). In this scenario, the switch of each Tx chain may require different times and result in different switching gaps. It is essential for the network to know the resulting switching gaps in order to process received UL transmissions. This information also helps the network more efficiently schedule uplink transmissions across the configured UL carriers.

[0284] To avoid overly complex designs without tangible gains towards manageable and scalable dynamic multi-carrier UL operation in practical scenarios, some necessary limitations may be necessary. For example, it may not be necessary to support all possible combinations for UL Tx switching between configured bands and / or carriers. For example, there may be no motivation to support all two simultaneous bands from / across four configured bands, which would result in (4C2) = 6 different states.

[0285] Furthermore, for new Tx switching scenarios, some restrictions on UL Tx switching may be required. For example, whether both Tx chains can be switched simultaneously and / or whether at least one of them is not switched (e.g., fixed to use a specific carrier)? For example, in some scenarios, the resulting UL transmission may differ depending on which Tx chain is switched, and therefore some restrictions may be necessary to avoid uncertainty and / or overly complex designs. For example, the network may not be able to control the internal processes of all wireless devices. In these scenarios, some restrictions may be useful.

[0286] For example, in existing technology, a single switching period / gap is reported and used for a pair of bands, including a single (e.g., the same) Tx switching between the two bands. If switching between any two of the M (M>2) configured bands were allowed, new Tx switching scenarios (e.g., Tx switching and / or any switching of two Txs between the same two bands) could emerge, which are not supported by current standards. New Tx switching scenarios could result in new / different switching periods, for example, depending on the UE's RF hardware for the two Tx chains. For example, if Tx switching is left to the UE implementation, the same carrier switching could result in different Tx switching (e.g., based on the UE implementation) and therefore different switching gaps, which could affect the resulting UL transmission due to puncturing.

[0287] For successful reception of UL transmissions at the network side, it is essential to address the new Tx switching scenarios so that the UE and the network have a common understanding of the corresponding switching periods in each scenario. This information allows the network to better schedule UL transmissions across the M configured bands.

[0288] Furthermore, if the UE implementation randomly switches Tx channels and / or RF chains and antenna connectors at the TTI level based on scheduling commands, the UE power consumption of the UE will increase. To limit dynamic Tx switching scenarios, enable switching Tx decisions, and reduce power consumption, it may be desirable to define UE behavior for new scenarios.

[0289] The embodiments propose one or more dynamic Tx switching operations, as well as RRC signaling to enable new switching scenarios within the proposed operations, so that the network can control / predict the UE's UL Tx switching potential (thus enhancing UL processing / scheduling). The embodiments allow the UE to determine how to map each of two Tx chains / antennas to M (M>2) UL carriers / bands and which Tx to use for which band in new and emerging switching scenarios. The Tx chain to use / switch for each transmission may not be explicitly indicated by the network (and may remain UE implementation). The exemplary embodiments may provide some guidelines / frames to help the network and the UE have a mutual understanding of Tx switching gaps in new switching scenarios. For example, the UE may implicitly determine and switch / use Tx chains based on the embodiments.

[0290] In some embodiments, the network may configure multiple (e.g., two or more) pairs of carriers / bands (i.e., 2) of the M carriers / bands for dynamic UL Tx switching operations. For example, the network may indicate to the UE to use one pair of carriers at a time for dynamic UL Tx switching, e.g., based on carrier pair activation. The UE may change / switch the active carrier pair, e.g., deactivate the first carrier pair and activate the second carrier pair, based on some (L1 / L2) signaling and / or timer and / or indication. The pairing mechanism may be used to restrict Tx switching scenarios and band combinations. For example, the network may have the opportunity to configure carrier / band pairs where Tx switching brings visible gains. The pairing mechanism may be scalable and may enable the network and UE to reuse existing Tx switching frameworks based on one pair of (active) carriers / bands without requiring cell reconfiguration.

[0291] In some embodiments, the network may configure an anchor carrier (which can be, e.g., two Tx antennas) and multiple switched carriers across M−1 bands. The anchor carrier-based mechanism in example embodiments may extend the existing Tx switching framework by restricting Tx switching scenarios, allowing the UE to switch a single (e.g., the same) Tx chain between M (M>2) carriers / bands. The network may indicate the anchor carrier to the UE at the time for dynamic UL Tx switching, for example, based on activation of a carrier pair. The UE may change / switch the anchor carrier, e.g., stop a first anchor carrier and activate a second anchor carrier, based on some (L1 / L2) signaling and / or timer and / or indication. The anchor mechanism may be scalable and may enable more dynamic utilization of configured bands in a systematic approach.

[0292] Some embodiments may apply to UEs configured with more than two uplink carriers from more than two frequency bands. Some embodiments may apply to UEs with more than 2 Tx, e.g., 3 Tx, 4 Tx. Some embodiments may apply to UEs configured with UL carriers from several frequency bands that exceed their UL Tx capabilities.

[0293] A 2Tx UE may be a UE that has / contains two UL Tx channels / chains / antennas (but not more). A 2Tx UE may be capable of two UL Tx antenna connectors.

[0294] A 2Tx UE may not be able to switch both Tx chains / antennas simultaneously. For example, it may take a significant amount of time / duration for the UE to switch both Tx chains / antennas simultaneously. Embodiments may enable the UE to perform UL Tx switching without requiring unnecessary switching of both Tx chains / antennas simultaneously. For example, in some embodiments, the UE may not be able to switch 2Tx based on a scheduling command, but may be based on some specific switching command (e.g., via MAC-CE or a specific DCI format).

[0295] The wireless device may receive one or more messages from at least one base station. The one or more messages may include one or more RRC messages (e.g., RRCSetup and / or RRCReconfiguration) and / or SIBs (e.g., SIB1). The one or more messages may configure one or more serving cells for the UE (e.g., PCell, PScell, SPcell, and / or SCell). For example, the one or more messages may include information elements and / or configuration parameters indicating one or more serving cells.

[0296] One or more serving cells may be associated with the same TAG (Timing Advance Group). One or more serving cells may be associated with different TAGs. One or more serving cells may be associated with the same cell group (e.g., master cell group or secondary cell group). One or more serving cells may be associated with different cell groups.

[0297] A serving cell may include one or more uplink carriers, e.g., a (normal) uplink (UL or NUL) carrier and / or a complementary uplink (SUL) carrier. In one embodiment, a UE may receive one or more messages including configuration parameters indicating multiple uplink carriers for the UE. The multiple UL carriers may be associated with / are carriers of the same serving cell (e.g., NUL and SUL) or different serving cells (e.g., UL CA and / or NR-DC and / or EN-DC and / or NE-DC).

[0298] In one embodiment, a UE may be configured with multiple bands in the uplink. For example, the multiple UL carriers may be from different frequency bands. For example, each UL carrier of the multiple UL carriers may belong to a different band. For example, a first UL carrier may belong to a first band, a second UL carrier may belong to a second band, a third UL carrier may belong to a third band, and a fourth UL carrier (if present) may belong to a fourth band. For example, a UE may be configured with at least one SUL carrier. For example, a UE may be configured with multi-carrier inter-band carrier aggregation. For example, a UE may be configured with multi-carrier dual connectivity.

[0299] The UE may have / include two UL Tx chains / antennas. The UE's UL Tx chains / antennas may not be capable of supporting simultaneous UL transmissions on two (or more) different frequency bands (e.g., having two or more different center frequencies). The UE may reconfigure / retune the Tx antenna / RF chain to support simultaneous UL transmissions on two (or more) different frequency bands. For example, the UE may move / switch the UL Tx chain / antenna from a first UL carrier in a first band to a second UL carrier in a second band.

[0300] In one embodiment, a UE may be configured with multiple uplink carriers within the same frequency band (e.g., intra-band CA). The UE's UL Tx chains / antennas may support simultaneous UL transmissions on the same frequency band (e.g., same center frequency). The UE may not need to reconfigure / retune its Tx antennas / RF chains to support simultaneous UL transmissions over carriers in the same frequency band. For example, because the same UL Tx configuration may support simultaneous UL transmissions over different carriers within the same band (e.g., subject to power limitations), the UE may not move / switch its UL Tx chains / antennas between bands.

[0301] A UE (e.g., with 2Tx capability, including / having 2Tx chains / antennas) may be configured with three or more UL carriers (e.g., M UL carriers, M>2) from different frequency bands (e.g., M bands, M>2). For example, a first UL carrier may belong to a first band, a second UL carrier may belong to a second band, a third UL carrier may belong to a third band, and a fourth UL carrier (if present) may belong to the fourth band.

[0302] The UE may be configured with (dynamic) UL Tx switching between configured UL carriers. For example, one or more messages may indicate to the UE that UL Tx switching is configured / enabled / used for M (M>2) UL carriers (e.g., via uplinkTxSwitching per UL carrier).

[0303] The UE may be configured with one or more UL carrier "pairs" (e.g., pairs of UL carriers) from the M configured UL carriers. The UE may be configured with two or more UL carrier pairs for dynamic UL Tx switching. The UE may receive one or more messages (e.g., RRC messages and / or SIBs) indicating UL carrier pairs, each UL carrier pair including two UL carriers from the configured UL carriers. The one or more messages may include information elements and / or configuration parameters indicating UL carrier pairs from the multiple configured UL carriers.

[0304] A UL carrier pair (e.g., a UL carrier coupling, or a UL carrier twin, or a set of two UL carriers) may include two UL carriers. The two uplink carriers of a carrier pair may consist of a UL carrier. For example, a first UL carrier pair may include a first UL carrier and a second UL carrier. For example, one or more messages may indicate:

[0305] One or more serving cells associated with the two UL carriers of the carrier pair may or may not be activated (e.g., via one or more cell activation mechanisms). For example, at least one of the one or more serving cells may be a dormant cell.

[0306] Figure 26 shows an example of UL carrier pairs configured for dynamic UL Tx switching. As shown in Figure 26, a UE (e.g., a 2Tx UE) can be configured with four UL carriers on four different bands. The UE can be configured with four UL carrier pairs. For example, UL carrier pair #1 includes UL carrier 1 and UL carrier 2. For example, UL carrier pair #2 includes UL carrier 1 and UL carrier 3. For example, UL carrier pair #3 includes UL carrier 2 and UL carrier 4. For example, UL carrier pair #4 includes UL carrier 3 and UL carrier 4.

[0307] Note that in Figure 26, although (4C2) = 6 carrier pairs can be configured, the network limits the combinations by configuring 4 pairs (2 pairs are excluded and not configured). The 4 configured UL carrier pairs can be configured based on allowable / desired carrier switching scenarios.

[0308] At a given time, the UE may use one UL carrier pair, for example, based on UL Tx switching. For example, as shown in FIG. 26, the UE may use UL carrier pair #T1 during (T0, T1), UL carrier pair #T2 during (T1, T2), UL carrier pair #3 during (T2, T3), and UL carrier pair #4 after T3. The UE can switch the UL Tx chain / antenna between the two UL carriers of a pair (the pair in use, or active pair) during the associated time interval. The UE can switch the UL Tx chain / antenna between the two UL carriers of a pair based on the received scheduling command. For example, the UE can switch the Tx chain / antenna between UL carrier 1 and UL carrier 2 during (T0, T1) and between UL carrier 1 and UL carrier 3 during (T1, T2).

[0309] In one embodiment, one or more carrier pairs may have a common UL carrier. These pairs may be referred to as "common pairs." For example, in Figure 26, UL Carrier Pair #1 and UL Carrier Pair #2 have UL Carrier 1 in common.

[0310] In one embodiment, each UL carrier may be configured exclusively in one UL carrier pair. For example, UL carrier pairs may not have any UL carriers in common. For example, a UE may not expect to receive UL carrier configuration parameters that indicate that a UL carrier belongs to more than one UL carrier pair.

[0311] In one embodiment, a "carrier pair" may be referred to as a "band pair" based on a one-to-one mapping of an UL carrier and a band.

[0312] In one embodiment, one of the two UL carriers in a UL carrier pair is capable of 1 Tx (supports 1 Tx / one Tx antenna connector), and the other UL carrier in a UL carrier pair is capable of 2 Tx (supports 2 Tx / two Tx antenna connectors). For example, a UE may transmit a single UL transmission via a first UL carrier of a UL carrier pair capable of 1 Tx. For example, a UE may transmit a single UL transmission and / or a two-tiered UL transmission via a second UL carrier of a UL carrier pair capable of 2 Tx.

[0313] Figure 27 shows an example of signaling between a UE and a base station for carrier pair configuration. The UE may be configured with M (M>2) UL carriers. As shown in the figure, the UE may receive an RRC configuration indicating UL carrier pairs (e.g., N UL carrier pairs, N>1) (UL carrier pair #0, UL carrier pair #1, ..., UL carrier pair #N-1).

[0314] In one embodiment, each UL carrier may be configured with an UL carrier index, e.g., UplinkCarrier-Id={0, 1, ..., M-1}. For example, the RRC configuration may include a parameter indicating the UL carrier index for each configured UL carrier. The RRC configuration may include, for example, an information element for dynamic UL Tx switching, indicating N UL carrier pairs. For example, the RRC configuration may include a field indicating a first UL carrier pair with a first index (e.g., UL UplinkCarrierPair-Id=i, i=0, 1, ..., N-1) that includes a first UL carrier (e.g., UL carrier #x, x=0, 1, ..., M-1) and a second UL carrier (e.g., UL carrier #y, y=0, 1, ..., M-1, x≠y).

[0315] In one embodiment, the RRC configuration may indicate that for / in a UL carrier pair, each UL carrier supports 1 Tx or 2 Tx. For example, for UL carrier pair #i={UL carrier #x, UL carrier #y}, the RRC configuration parameters may indicate that UL carrier #x is "carrier 1," which may be, for example, a 1 Tx / 1 Tx antenna connector, and UL carrier #y is "carrier 2," which may be, for example, a 2 Tx / 2 Tx antenna connector. In one example, the RRC message may include an information field for each UL carrier pair that explicitly indicates the Tx capability of each configured UL carrier (e.g., 1 Tx or 2 Tx).

[0316] In one embodiment, the UE may determine the Tx capability of each UL carrier of a UL carrier pair. For example, the UE may receive a configuration parameter indicating a UL carrier pair #i = {UL carrier #x, UL carrier #y}. The configuration parameter may implicitly indicate the Tx capability of each UL carrier of the UL carrier pair, for example, based on a rule. The rule may be based on the order of the UL carriers in the RRC field that configures / indicates the corresponding UL carrier pair. For example, the UE may determine that the first (e.g., left) UL carrier is capable of 1 Tx (e.g., carrier #x is "carrier 1" of the pair) and the second (e.g., right) UL carrier is capable of 2 Tx (e.g., carrier #y is "carrier 2" of the pair), or vice versa. In one embodiment, the rule may be based on the index of the UL carrier within the UL carrier pair. For example, the UE may determine that the UL carrier with the smaller carrier index is capable of 1 Tx and the other UL carrier with the larger carrier index is capable of 2 Tx, or vice versa.

[0317] In one embodiment, the Tx capability of a UL carrier may be the same across multiple UL carrier pairs (e.g., carrier-specific parameters). For example, UL carrier #x may be capable of 1 Tx (or 2 Tx) regardless of the UL carrier pair. For example, if a first UL carrier pair and a second UL carrier pair include UL carrier #x, the Tx capability of UL carrier #x is the same across both UL carrier pairs.

[0318] In one embodiment, the Tx capability of an UL carrier may differ among the multiple UL carrier pairs to which it belongs (e.g., carrier pair-specific parameters). For example, UL carrier #x may be capable of 1 Tx (or 2 Tx) depending on the UL carrier pair configuration. For example, if a first UL carrier pair and a second UL carrier pair include UL carrier #x, the Tx capability of UL carrier #x in the first UL carrier pair may be 1 Tx, and the Tx capability of UL carrier #x in the second UL carrier pair may be 2 Tx.

[0319] In one embodiment, for each configured UL carrier, a field / parameter may indicate the UL carrier pair to which this UL carrier belongs. For example, it may be a bitmap with a maximum size of N=(M_select2), where each bit indicates whether the corresponding pair is defined using the configured UL carrier. For example, bit #0=0 means that UL carrier pair #0 does not include this UL carrier, bit #1=0 means that UL carrier pair #1 does not include this UL carrier, and bit #2=1 means that UL carrier pair #2 includes this UL carrier. In one embodiment, for each carrier, there are a maximum of M-1 pairs for UL Tx switching, e.g., the sum of the bitmap may be less than or equal to M-1. In one embodiment, for each carrier, there is one pair for UL Tx switching, e.g., the sum of the bitmap may be equal to 1.

[0320] In one embodiment, a one-to-one mapping may be defined between configured UL carriers. For example, RRC may indicate whether each UL carrier is 1Tx capable or 2Tx capable. RRC may indicate a one-to-one mapping between 1Tx UL carriers and 2Tx UL carriers. For example, each one-to-one mapping may indicate a UL carrier pair. In one embodiment, the mapping may be explicitly indicated by an RRC field / parameter. In one embodiment, the mapping may be implicit, for example, based on a common configuration between two UL carriers and / or based on the UL carrier index of the UL carrier. For example, RRC may tag each 1Tx UL carrier with an index from a first set and each 2Tx UL carrier with an index from a second set, and a mapping may be defined between the indexes of the first set and the indexes of the second set. For example, {UL carrier #1, UL carrier #3} may be configured as a 1 Tx carrier and may be tagged with indices {1,2}, and {UL carrier #2, UL carrier #4} may be configured as a 2 Tx carrier and may be tagged with indices {1,2}. The UE may determine the first UL carrier pair as {UL carrier #1, UL carrier #2} and the second UL carrier pair as {UL carrier #3, UL carrier #4} (e.g., index 1:1 and index 2:2).

[0321] In one embodiment, when a 2Tx carrier is switched, the corresponding 1Tx carrier is also switched based on the configuration of the UL carrier pair.

[0322] As shown in Figure 27, the UE may receive an indication of activation of a UL carrier pair from a base station. For example, the UE may receive DCI and / or MAC-CE (e.g., L1 / L2 signaling via MAC-CE or a specific DCI format indicating a switching / activation command) indicating activation of the UL carrier pair. For example, downlink signaling may indicate that UL carrier pair #i = {UL carrier #x, UL carrier #y} has been activated.

[0323] When a UL carrier pair is activated, the UE may use two uplink carriers of the activated UL carrier pair for UL transmission, e.g., based on UL Tx switching. For example, the UE's UL transmissions (e.g., excluding SRS) may be limited to the two UL carriers of the activated UL carrier pair (e.g., UL carrier #x and UL carrier #y). In one embodiment, the UE may not expect to receive scheduling commands (e.g., UL grants for PUSCH and / or PUCCH and / or PRACH and / or one or more reference signals) for UL carriers outside / not belonging to the active UL carrier pair. In one embodiment, the UE may not monitor a core set / search space associated with a UL carrier not belonging to the active UL carrier pair. In one embodiment, the UE may stop semi-static UL transmissions (e.g., configured grant type 1 and / or configured grant type 2) on UL carriers (e.g., excluding SRS) not belonging to the active UL carrier pair.

[0324] At a given time, a single UL carrier pair may be activated. For example, the UE may activate the first UL carrier pair in response to, for example, an indication of activation of the first UL carrier pair. In one embodiment, the RRC configuration may include a field / parameter indicating a default / initial / primary UL carrier pair (e.g., firstActiveCarrierPair and / or defaultPair and / or initialPair). For example, the default / initial UL carrier pair may be activated upon receiving an RRC configuration, and the RRC configuration may indicate that UL Tx switching is configured. For example, the two UL carriers of the first UL carrier pair may be associated with the active serving cell.

[0325] In one embodiment, the UE may receive an indication to change / switch the UL carrier pair, for example, via DCI / MAC-CE. Upon receiving the UL carrier pair switching indication, the UE may deactivate the first UL carrier pair (which is active) and activate the second UL carrier pair. For example, the DCI / MAC-CE containing the UL carrier pair switching command may indicate the second UL carrier pair. For example, one UL carrier pair out of N configured carrier pairs may be active at a given time.

[0326] In one embodiment, the UE may decide to activate the default / initial UL carrier pair in response to PCell / PScell ​​activation.

[0327] In one embodiment, the UE may decide to activate the UL carrier pair in response to activation of one or more serving cells associated with at least one UL carrier of the UL carrier pair.

[0328] In one embodiment, the UE may decide to switch to a default / initial UL carrier pair in response to an outage of one or more serving cells associated with at least one UL carrier of an active UL carrier pair.

[0329] In one embodiment, the UE can decide to switch to a default / initial UL carrier pair in response to expiration of a timer. For example, the RRC message may configure the UL carrier pair switching timer and / or indicate the timer's duration. The timer can help avoid excessive UL carrier pair changes when not necessary (e.g., insufficient UL grants are received based on Tx switching). For example, the timer can be reset in response to receiving a scheduling command (e.g., a UL grant) for any of the UL carriers of the active UL carrier pair.

[0330] Embodiments enable the use of L1 / L2 and / or automatic decisions (e.g., based on timers) to change the configured UL carrier pair instead of RRC signaling, thus significantly reducing dynamic Tx switching delays. Based on embodiments, a UE can perform dynamic UL Tx switching between two UL carriers of an active UL carrier pair using existing switching frameworks. For example, the UE can switch one Tx between carrier 1 and carrier 2 in / of an active carrier pair based on a scheduling command. RRC signaling may indicate UL Tx switching parameters per UL carrier pair. The RRC signaling may indicate which carriers in the carrier pair are capable of 1 Tx and which are capable of 2 Tx. For example, the RRC configuration may indicate, for each configured UL carrier pair, the first UL carrier as carrier 1 (e.g., capable of 1 Tx) and the second uplink carrier as carrier 2 (e.g., capable of 2 Tx). The UE may use one Tx chain / antenna for UL transmission over the second carrier (i.e., carrier 2 of the pair) and / or switch another Tx chain / antenna between the first and second UL carriers of the pair. The UE may apply respective Tx switching gaps based on the two UL carriers of the active UL carrier pair and based on the respective band combinations.

[0331] When switching UL carrier pairs, common band switching may be allowed / defined to reduce startup delays. For example, one of the carriers may be common between the new pair and the old pair (before and after the switch). For example, the first carrier of the new pair and the second carrier of the old pair may belong to the same / common frequency band. In one embodiment, the common carrier and / or carrier associated with the common band may be capable of 1 Tx (i.e., "carrier 1"). In one embodiment, the common carrier and / or carrier associated with the common band may be capable of 2 Tx (i.e., "carrier 2").

[0332] Figure 28 shows an example of UL carrier pairs configured for dynamic UL Tx switching. In this example, carrier pair switching based on common bands and / or common carriers is illustrated. As shown in the figure, each carrier pair switch involves a single carrier switch, such as carrier 2 switching to carrier 4 on T1 (carrier 1 / band 1 is common) and carrier 1 switching to carrier 3 on T2 (carrier 4 / band 4 is common). The figure proposes a method for assigning Tx chains / antennas to UL carriers based on a pairing mechanism. As shown in the figure, Tx-1 is used for the 2-Tx carrier (carrier that can be two Tx antenna connectors) of each UL carrier pair, and Tx-2 (shown in gray) switches between the 1-Tx carrier and the 2-Tx carrier of the UL carrier pair.

[0333] In one embodiment, the wireless device may receive one or more messages including configuration parameters indicating multiple uplink carriers for the UE. The multiple UL carriers may be associated with / associated with the same serving cell (e.g., NUL and SUL) or different serving cells (e.g., UL CA and / or NR-DC and / or EN-DC and / or NE-DC).

[0334] In one embodiment, a UE may be configured with multiple bands in the uplink. For example, the multiple UL carriers may be from different frequency bands. For example, each UL carrier of the multiple UL carriers may belong to a different band. For example, a first UL carrier may belong to a first band, a second UL carrier may belong to a second band, a third UL carrier may belong to a third band, and a fourth UL carrier (if present) may belong to a fourth band. For example, a UE may be configured with at least one SUL carrier. For example, a UE may be configured with multi-carrier inter-band carrier aggregation. For example, a UE may be configured with multi-carrier dual connectivity.

[0335] The UE may be configured with (dynamic) UL Tx switching between configured UL carriers. For example, one or more messages may indicate to the UE that UL Tx switching is configured / enabled / used for M (M>2) UL carriers (e.g., via uplinkTxSwitching per UL carrier).

[0336] The UE may receive one or more messages (e.g., RRC messages and / or SIBs) indicating one or more "anchor" UL carriers. The anchor UL carrier may be a UL carrier that can be two transmit antenna connectors (e.g., a 2-Tx carrier). A UE (e.g., a 2-Tx UE, or a UE with two Tx chains / antennas) may use one (e.g., the first) Tx chain / antenna for the anchor UL carrier. For example, the first Tx chain / antenna may not be switched between UL carriers in dynamic UL Tx switching. For example, the first Tx chain / antenna may be fixed / tuned / configured to the anchor UL carrier frequency.

[0337] In one embodiment, the anchor UL carrier may be a UL carrier that can be one transmit antenna connector (e.g., 1 Tx carrier). A UE (e.g., a 2 Tx UE, or a UE with two Tx chains / antennas) may use one (e.g., the first) Tx chain / antenna for the anchor UL carrier. For example, the first Tx chain / antenna may be switched between UL carriers in dynamic UL Tx switching.

[0338] In one embodiment, the first Tx chain may be fixed / tuned / configured to the UL carrier of the frequency band to which the anchor carrier belongs.

[0339] In one embodiment, the "anchor" UL carrier may be referred to as a default UL carrier, or an active UL carrier, or a common UL carrier, or a primary UL carrier, etc.

[0340] In one embodiment, an anchor UL carrier may be activated. For example, the UE may receive downlink signaling (e.g., RRC and / or DCI and / or MAC-CE signaling) indicating that a first UL carrier is activated as the anchor / active / common / default UL carrier.

[0341] The anchor UL carrier may be associated with a set / group of second UL carriers. For example, one or more messages may include configuration parameters indicating one or more sets / groups of second UL carriers. In one embodiment, the group of second UL carriers may include one or more UL carriers, each of which may be a single transmit antenna connector (e.g., one Tx carrier). A UE (e.g., a 2Tx UE, or a UE with two Tx chains / antennas) may use one (e.g., a first) Tx chain / antenna for the anchor UL carrier and may move / switch another (e.g., a second) Tx chain / antenna between the second UL carrier and / or the group of anchor UL carriers. For example, the second Tx chain / antenna may be switched based on dynamic Tx switching across UL carriers, including the anchor UL carrier and one or more second UL carriers associated with the anchor UL carrier.

[0342] In one embodiment, the group of second UL carriers may include one or more UL carriers that can be two transmit antenna connectors (e.g., two Tx carriers). A UE (e.g., a two Tx UE, or a UE with two Tx chains / antennas) may move / switch two (e.g., first and second) Tx chains / antennas between the group of second UL carriers and / or anchor UL carriers. For example, the two Tx chains / antennas may be switched based on dynamic Tx switching across one or more second UL carriers associated with the anchor UL carrier. For example, one of the two (e.g., first) Tx chains / antennas may be switched based on dynamic Tx switching across UL carriers that include the anchor UL carrier and one or more second UL carriers associated with the anchor UL carrier.

[0343] In one embodiment, one or more secondary UL carriers associated with the anchor UL carrier may be activated in response to activation of the primary / anchor UL carrier (e.g., may be used for dynamic UL Tx switching). In one embodiment, the anchor UL carrier may be activated. In one embodiment, at least one secondary UL carrier of the one or more secondary UL carriers associated with the primary / anchor UL carrier may be activated. The first / anchor UL carrier and the at least one secondary UL carrier may be used for dynamic UL Tx switching.

[0344] Throughout this disclosure, when two or more UL carriers are used for dynamic UL Tx switching, the UE may move one or more Tx chains / antennas across the two or more UL carriers based on the dynamic UL Tx switching. For example, the UE may send UL transmissions using two or more UL carriers based on the dynamic UL Tx switching, e.g., based on scheduling commands and / or received UL grants and / or semi-static UL grants. In one embodiment, the dynamic UL Tx switching may be responsive to a TDD configuration and / or slot format indicating uplink "U" slots / symbols / subframes of the UL carriers.

[0345] In one embodiment, the RRC message may configure one or more sets / groups / lists of UL carriers. For example, the set of UL carriers may include an anchor UL carrier and one or more secondary UL carriers (e.g., switched UL carriers). The UE may activate and / or decide to activate a first set of UL carriers among the set of one or more UL carriers. For example, the UE may receive an indication of activation of the first UL carrier set (or the first UL carrier set). The UE may use the first set of UL carriers for dynamic UL Tx switching. For example, the UE may send UL transmissions using the first set of UL carriers based on dynamic UL Tx switching, e.g., based on a scheduling command and / or a received UL grant and / or semi-static UL grant.

[0346] In one embodiment, the UE may be configured with multiple anchor UL carriers, e.g., a set / group / list of anchor UL carriers. The set / group / list of anchor UL carriers may include UL carriers that can be dual Tx antenna connectors. The UE may receive downlink signaling (e.g., RRC / DCI / MAC-CE, e.g., a specific DCI format including MAC-CE or an activation / switching command) that includes an indication to change / switch the anchor UL carrier. For example, the UE may decide to switch / change the anchor UL carrier in response to expiration of a first timer, e.g., a UL Tx switching timer.

[0347] For example, the RRC message may indicate the value / duration of the UL Tx switching timer. The first time scale for first / anchor carrier switching may be larger than the second time scale for second carrier switching (e.g., based on a scheduling command). This may help reduce the power consumption and delay / gap required for Tx switching (e.g., a 2Tx switching scenario). The network may use the UL Tx switching timer to manage the time scale. For example, the anchor carrier may not change while the UL Tx switching timer is running. For example, the second carrier may change / switch between sets of UL carriers while the UL Tx switching timer is running. For example, upon expiration of the timer, the anchor UL carrier may switch / change between sets / lists of anchor UL carriers.

[0348] The UE may activate a first anchor UL carrier. The first anchor UL carrier may be associated with a PCell / PScell. The first anchor UL carrier may be associated with a cell having a smallest cell index. The first anchor UL carrier may have a smallest UL carrier index among the anchor UL carriers and / or multiple configured UL carriers. In one embodiment, the first anchor UL carrier may be capable of being one Tx antenna connector. In one embodiment, the first anchor UL carrier may be capable of being two Tx antenna connectors.

[0349] The UE may switch / change the anchor / active UL carrier from the first anchor UL carrier to the second anchor UL carrier. For example, the UE may stop the first anchor UL carrier and / or start the second anchor UL carrier. For example, downlink signaling (e.g., RRC / DCI / MAC-CE) may indicate the second anchor UL carrier.

[0350] Each anchor UL carrier may be configured with an associated set of secondary UL carriers. For example, a set of secondary UL carriers may be one Tx antenna connector. In one embodiment, a set of secondary UL carriers may be two Tx antenna connectors.

[0351] In one embodiment, the UE may activate a first set of second UL carriers associated with a first anchor UL carrier. The UE may switch / change from the first set of second UL carriers to a second set of second UL carriers. For example, the UE may stop the first set of second UL carriers and / or activate the second set of second UL carriers. For example, the second set of second UL carriers may be associated with a second anchor UL carrier. For example, the second anchor UL carrier may be activated.

[0352] The UE may switch / change an active set of UL carriers including an active anchor UL carrier and / or an anchor UL carrier and a set of second UL carriers associated with the anchor UL carrier. For example, the UE may change / switch from a first anchor UL carrier to a second anchor UL carrier as the active anchor UL carrier. For example, the UE may change / switch from a first set of UL carriers to a second set of UL carriers as the active set of UL carriers. In one embodiment, the switching may be in response to receiving an indication of switching via downlink signaling (e.g., RRC and / or MAC-CE and / or DCI). In one embodiment, the switching may be in response to expiration of a first timer, e.g., a carrier / UL Tx switching timer.

[0353] The UE may use the active anchor UL carrier and one or more active secondary UL carriers associated with the active anchor UL carrier to send UL transmissions based on the dynamic UL Tx switching. The UE may use an active set of UL carriers to send UL transmissions based on the dynamic UL Tx switching.

[0354] Figure 29 shows an example of dynamic UL Tx switching across four UL carriers in four different bands. In this example, a UE is configured with a set of four UL carriers: UL carrier 1, UL carrier 2, UL carrier 3, and UL carrier 4. The UE may determine that UL carrier 4 is the anchor UL carrier of the set. For example, UL carrier 4 may be configured via RRC signaling as the anchor UL carrier. The UE may determine that UL carrier 1, UL carrier 2, and UL carrier 3 are secondary UL carriers associated with the anchor UL carrier (UL carrier 4). For example, the RRC signaling may indicate the association. The UE may activate anchor UL carrier 4. The UE may activate the set of UL carriers that includes / associates with UL carrier 4.

[0355] In the example shown in FIG. 29, the UE uses one Tx chain / antenna (Tx-1) for UL transmission over UL carrier 4 (anchor UL carrier) and / or switches the other Tx chain / antenna (Tx-2) among / across a set of UL carriers (UL carrier 1 and UL carrier 2 and UL carrier 3 and UL carrier 4). For example, at time T0, the UE may transmit one UL transmission using Tx-1 over UL carrier 4 and / or one UL transmission using Tx-2 over UL carrier 3. The UE may receive a UL grant for UL carrier 4 at T1. The UL grant may include a two-tiered UL grant. For example, the UE may switch Tx-2 to UL carrier 4. The UE transmits two-tiered UL transmission over UL carrier 4 using Tx-1 and Tx-2. The UE may switch Tx-2 to UL carrier 1 at T2, e.g., for a single-tier UL transmission via UL carrier 1 and / or in response to a TDD configuration and / or slot format indicating uplink "U" slots / symbols / subframes of UL carrier 1. The UE may receive a UL grant for UL carrier 4 at T3. The UL grant may include a two-tiered UL grant. For example, the UE may switch Tx-2 to UL carrier 4. The UE transmits a two-tiered UL transmission via UL carrier 4 using Tx-1 and Tx-2.

[0356] In one example, the UE may receive an indication (e.g., a switching command) to switch the anchor UL carrier from carrier 4 to carrier 2. For example, the UE may receive a MAC-CE / DCI including the indication. The UE may use one Tx chain / antenna (Tx-1) for UL transmission over UL carrier 2 (anchor UL carrier) and / or can switch the other Tx chain / antenna (Tx-2) among / across the set of UL carriers (UL carrier 1 and UL carrier 2 and UL carrier 3 and UL carrier 4).

[0357] The UE may expect to be scheduled with two-port / two-tier UL transmission to the (active) anchor UL carrier.

[0358] In one embodiment, the RRC configuration of the anchor UL carrier or UL carrier pair may be responsive to UE capabilities. For example, the UE may transmit capability information including a field indicating that the UE is incapable of simultaneous switching of two Tx chains / antennas. For example, the UE may not anticipate simultaneous switching of both Tx chains / antennas, which may not be based on a scheduling command but may be based on a specific switching / activation command indicated by the MAC-CE and / or a specific DCI format, for example, for UL carrier pair switching and / or anchor UL carrier switching / activation.

[0359] Throughout this disclosure, "carrier" may be replaced by "band," eg, UL band pair, and / or anchor band, and / or band switching, etc.

[0360] In one embodiment, the UE may receive an RRC message including a configuration parameter indicating each configured UL carrier as either Carrier 1 (capable of 1 Tx) or Carrier 2 (capable of 2 Tx). The network may configure two sets / groups of UL carriers, e.g., a first group of UL carriers (capable of 1 Tx) as Carrier 1 and a second group of UL carriers (capable of 2 Tx) as Carrier 2. In one example, the first half / portion of configured UL carriers that include a first half / portion of carrier indexes with lower values ​​may comprise the first group, and the second half / portion of configured UL carriers that include a second half / portion of carrier indexes with higher values ​​may comprise the second group, or vice versa.

[0361] In one embodiment, which carriers are allowed to be switched between may be predefined / configured. For example, switching between carriers of the same / opposite Tx capabilities may be allowed. In one embodiment, at a given time, a UE is not expected to be performing dynamic Tx switching using two carriers with the same Tx capabilities, e.g., one carrier supporting 1Tx and the other supporting 2Tx. In one embodiment, if at a given time, a UE uses two carriers supporting 2Tx, the UE is not expected to simultaneously transmit two-port transmissions on two UL carriers.

[0362] Figure 30 shows an example of dynamic UL Tx switching according to an embodiment. In this example, received RRC signaling may indicate that UL Carrier 2 and UL Carrier 3 can be two UL Tx antenna connectors, and UL Carrier 1 can be one UL Tx antenna connector. In this example, the UE switches both Tx chains / antennas from UL Carrier 2 to UL Carrier 3 at time T1. For example, the UE may transmit a two-port UL transmission using both Tx chains / antennas via UL Carrier 3. A previous UL transmission may be another two-port UL transmission using both Tx chains / antennas via UL Carrier 2. Respective switching gaps for switching both Txs associated with band combinations including Band 2 and Band 3 may be applied, during which the UE may not be expected to transmit on the (two) UL carriers.

[0363] 30, UL Carrier 1 may be an anchor UL carrier, and UL Carrier 2 and UL Carrier 3 may be secondary UL carriers associated with UL Carrier 1.

[0364] Figure 31 shows an example of dynamic UL Tx switching. In this example, the UE is not capable of dual UL transmission. This embodiment may be referred to as a switched UL transmission mode (e.g., TDM). For example, received RRC signaling may indicate / configure UL Carrier 2 and UL Carrier 3 as switched UL carriers.

[0365] The wireless device may receive one or more messages including configuration parameters for one or more cells. The wireless device may receive one or more Radio Resource Control (RRC) messages indicating multiple uplink carrier pairs, each uplink carrier pair including two uplink carriers to which a transmit antenna may switch. The wireless device may switch a first transmit antenna from a first uplink carrier of the first uplink carrier pair to a second uplink carrier of the first uplink carrier pair. The first uplink carrier pair may be selected from the multiple uplink carrier pairs. The wireless device may send an uplink transmission using the first transmit antenna over the second uplink carrier.

[0366] The one or more RRC messages may further indicate that uplink transmission switching is configured for the wireless device using an uplink carrier pair of the multiple uplink carrier pairs. The wireless device may select a first uplink carrier pair from the multiple uplink carrier pairs. The first uplink carrier may be configured in a first frequency band. The second uplink carrier may be configured in a second frequency band. The first uplink carrier and the second uplink carrier may be configured for dual connectivity. The first uplink carrier and the second uplink carrier may be configured for carrier aggregation. The carrier aggregation may be inter-band carrier aggregation. One of the first uplink carrier and the second uplink carrier may be configured for a complementary uplink. The transmitter of the wireless device may include a first transmit antenna and a second transmit antenna. The number of transmit antennas of the wireless device may be two. The first transmit antenna may be switched between the first uplink carrier and the second uplink carrier. The second transmit antenna may be used for uplink transmission via the first uplink carrier. The switching may be responsive to receiving a scheduling command for the second uplink carrier, the scheduling command may indicate a one-port uplink transmission.

[0367] The wireless device may switch the first transmit antenna from the second uplink carrier to the first uplink carrier. For example, switching the first transmit antenna from the second uplink carrier to the first uplink carrier includes (re)configuring the first transmit antenna to be used for transmissions scheduled over the first uplink carrier. For example, switching the first transmit antenna from the second uplink carrier to the first uplink carrier includes (re)configuring the first transmit antenna to not be used for the second uplink carrier. The switching may be responsive to receiving a second scheduling command for the first uplink carrier. The second scheduling command may indicate a two-port uplink transmission. The wireless device may transmit a two-port (e.g., dual) uplink transmission over the first uplink carrier using the first transmit antenna and the second transmit antenna. The wireless device may support a two-port (e.g., dual) uplink transmission using the first transmit antenna and the second transmit antenna. The wireless device may receive configuration parameters for a cell group. The cell group may include a first uplink carrier and a second uplink carrier indicating that two-port (e.g., dual) uplink transmission is enabled via the first uplink carrier. The wireless device may select a first uplink carrier pair from among multiple uplink carrier pairs based on receiving an indication of activation of the first uplink carrier pair. One or more RRC messages may include an indication of activation of the first uplink carrier. The wireless device may receive a downlink signal including an indication of activation of the first uplink carrier. The downlink signal may be downlink control information (DCI) based on a first format. The downlink signal may be a medium access control element (MAC-CE) including an indication of activation of the first uplink carrier. The indication of activation of the first uplink carrier may be in response to expiration of a timer at a higher layer.

[0368] The one or more RRC messages may further indicate to the wireless device a configuration of a plurality of cells including a plurality of uplink carriers, including two uplink carriers of a first uplink carrier pair. Each uplink carrier of the plurality of uplink carriers may be associated with a respective frequency band. For each uplink carrier pair, the one or more RRC messages may include respective parameters for uplink transmission switching. The respective parameters for uplink transmission switching for each uplink carrier pair may include an indication that one of the two uplink carriers of the respective uplink carrier pair can be one transmit antenna connector and another of the two uplink carriers can be two transmit antenna connectors. The respective parameters for uplink transmission switching for each uplink carrier pair may include an indication of an uplink transmission switching option (e.g., including Option 1 and / or Option 2 in an exemplary embodiment). The uplink transmission switching option may include switched uplink (e.g., Option 1 in an exemplary embodiment) or dual uplink (e.g., Option 2 in an exemplary embodiment). The parameters for uplink transmission switching may include an indication of a position of an uplink transmission switching period. The wireless device may transmit wireless device capability information indicating supported band combinations, including a first frequency band to which the first uplink carrier belongs and a second frequency band to which the second uplink carrier belongs. The capability information may further indicate an uplink transmission switching period associated with switching the first transmit antenna from the first uplink carrier to the second uplink carrier.

[0369] The wireless device may receive one or more radio resource control (RRC) messages indicating multiple uplink carrier pairs, each uplink carrier pair including two uplink carriers for uplink transmit antenna switching. The wireless device may determine to switch one of the uplink transmit antennas between two uplink carriers of a first uplink carrier pair from among the multiple uplink carrier pairs. The wireless device may transmit an uplink transmission using the uplink transmit antenna via the first uplink carrier pair.

[0370] The wireless device may receive one or more radio resource control (RRC) messages indicating a configuration of uplink carriers, each uplink carrier associated with a respective frequency band, first parameters for uplink transmission switching using a first carrier pair including a first uplink carrier and a second uplink carrier of the uplink carriers, and second parameters for uplink transmission switching using a second carrier pair including a third uplink carrier and a fourth uplink carrier of the uplink carriers. The wireless device may determine to switch between the first uplink carrier and the second uplink carrier in response to activation of the first carrier pair. The wireless device may transmit uplink transmissions via the first uplink carrier and the second uplink carrier based on the first parameters.

[0371] The wireless device may receive one or more radio resource control (RRC) messages indicating multiple uplink carriers, including a first uplink carrier associated with a first frequency band that can be transmitted using two transmit antennas and two or more second uplink carriers associated with a second frequency band different from the first frequency band that can be transmitted using one transmit antenna. The wireless device may switch the uplink transmit antenna between two uplink carriers of the multiple uplink carriers. Based on the switching, the wireless device may transmit an uplink transmission over the multiple uplink carriers.

[0372] The wireless device may transmit a two-port uplink transmission via a first uplink carrier and using the transmit antenna and the second transmit antenna. The wireless device may switch the uplink transmit antenna from the first uplink carrier to a second uplink carrier from two or more second uplink carriers. The wireless device may transmit a one-port uplink transmission via the second uplink carrier and using the transmit antenna. The wireless device may transmit a one-port uplink transmission via the first uplink carrier and using the second transmit antenna. The one or more RRC messages may further indicate two or more first uplink carriers, including a first uplink carrier that can be transmitted using two transmit antennas. The wireless device may switch the second transmit antenna from the first uplink carrier to a third uplink carrier, the third uplink carrier being selected from the two or more first uplink carriers. The wireless device may transmit a two-port uplink transmission via the third uplink carrier and using the transmit antenna and the second transmit antenna. The switching may be in response to an indication of activation of the third uplink carrier. The wireless device may receive a second RRC message including a parameter indicating that a third uplink carrier has been activated. The second RRC message may indicate that the first uplink carrier has been deactivated. The wireless device may receive a downlink signal including an indication of activation. The downlink signal may be downlink control information (DCI) based on the first format. The downlink signal may be a medium access control element (MAC-CE) including a transport block indicating activation. The indication may be in response to expiration of a timer at a higher layer.

Claims

1. A wireless device, one or more processors; Memory to store instructions and Equipped with The instructions, when executed by the one or more processors, receiving a radio resource control (RRC) reconfiguration or setup message including configuration parameters for at least one cell including a plurality of uplink carriers, the configuration parameters including: uplink switching using three or more uplink bands, wherein each uplink carrier of the plurality of uplink carriers is within a respective one of the three or more uplink bands; A plurality of uplink band pairs from the three or more uplink bands for the uplink switching, wherein the configuration parameters include, for each uplink band pair of the plurality of uplink band pairs, Uplink switching based on dual uplink, or Uplink switching based on switched uplink Multiple uplink band pairs, including individual parameters indicating whether they are configured with and based on a first uplink band pair of the plurality of uplink band pairs configured with uplink switching based on the dual uplink; a first uplink transmission on a first uplink band of the first uplink band pair; and a second uplink transmission on a second uplink band of the first uplink band pair. Sending and The wireless device causes the wireless device to perform the above.

2. The wireless device of claim 1, further comprising simultaneously transmitting the first uplink transmission and the second uplink transmission based on the first uplink band pair being configured with uplink switching based on the dual uplink.

3. The wireless device of claim 1, wherein the first uplink transmission is a first one-port physical uplink shared channel (PUSCH) transmission on a first uplink carrier of the plurality of uplink carriers on the first uplink band.

4. The wireless device of claim 1, further comprising transmitting capability information of the wireless device indicating a combination of supported bands including the first uplink band and the second uplink band.

5. A base station, one or more processors; Memory to store instructions and Equipped with The instructions, when executed by the one or more processors, transmitting a radio resource control (RRC) reconfiguration or setup message including configuration parameters of at least one cell including a plurality of uplink carriers, the configuration parameters including: uplink switching using three or more uplink bands, wherein each uplink carrier of the plurality of uplink carriers is within a respective one of the three or more uplink bands; A plurality of uplink band pairs from the three or more uplink bands for the uplink switching, wherein the configuration parameters include, for each uplink band pair of the plurality of uplink band pairs, Uplink switching based on dual uplink, or Uplink switching based on switched uplink Multiple uplink band pairs, including individual parameters indicating whether they are configured with and based on a first uplink band pair of the plurality of uplink band pairs configured with uplink switching based on the dual uplink; a first uplink transmission on a first uplink band of the first uplink band pair; and a second uplink transmission on a second uplink band of the first uplink band pair. Receiving and The base station causes the base station to perform the above.

6. The base station described in claim 5, further comprising simultaneously receiving the first uplink transmission and the second uplink transmission based on the first uplink band pair being configured with uplink switching based on the dual uplink.

7. A base station as described in claim 5, wherein the first uplink transmission is a first one-port physical uplink shared channel (PUSCH) transmission on a first uplink carrier of the plurality of uplink carriers on the first uplink band.

8. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors of a wireless device, receiving a radio resource control (RRC) reconfiguration or setup message including configuration parameters for at least one cell including a plurality of uplink carriers, the configuration parameters including: uplink switching using three or more uplink bands, wherein each uplink carrier of the plurality of uplink carriers is within a respective one of the three or more uplink bands; A plurality of uplink band pairs from the three or more uplink bands for the uplink switching, wherein the configuration parameters include, for each uplink band pair of the plurality of uplink band pairs, Uplink switching based on dual uplink, or Uplink switching based on switched uplink Multiple uplink band pairs, including individual parameters indicating whether they are configured with and based on a first uplink band pair of the plurality of uplink band pairs configured with uplink switching based on the dual uplink; a first uplink transmission on a first uplink band of the first uplink band pair; and a second uplink transmission on a second uplink band of the first uplink band pair. Sending and a non-transitory computer-readable medium for causing the wireless device to perform the steps of:

9. The non-transitory computer-readable medium of claim 8, further comprising simultaneously transmitting the first uplink transmission and the second uplink transmission based on the first uplink band pair being configured with uplink switching based on the dual uplink.

10. The non-transitory computer-readable medium of claim 8, wherein the first uplink transmission is a first one-port physical uplink shared channel (PUSCH) transmission on a first uplink carrier of the plurality of uplink carriers on the first uplink band.

11. The non-transitory computer-readable medium of claim 8, further comprising transmitting capability information of the wireless device indicating a supported band combination including the first uplink band and the second uplink band.

12. The wireless device of claim 1, wherein the configuration parameters further indicate at least one uplink carrier of the plurality of uplink carriers associated with each cell of the at least one cell.

13. The wireless device of claim 1, wherein the configuration parameters further indicate, for each uplink carrier of the plurality of uplink carriers, an individual frequency domain location within a frequency range of an individual band of the three or more uplink bands.

14. The wireless device of claim 1, wherein the second uplink transmission is a second one-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

15. The wireless device of claim 1, wherein the second uplink transmission is a second two-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

16. The base station of claim 5, wherein the configuration parameters further indicate at least one uplink carrier of the plurality of uplink carriers associated with each cell of the at least one cell.

17. The base station described in claim 5, wherein the configuration parameters further indicate, for each uplink carrier of the plurality of uplink carriers, an individual frequency domain location within a frequency range of an individual band of the three or more uplink bands.

18. The base station described in claim 5, wherein the second uplink transmission is a second one-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

19. The base station described in claim 5, wherein the second uplink transmission is a second two-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

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