Method and apparatus for communication

Abstract

A user equipment (UE) can perform sounding reference signal (SRS) switching by transmitting one or more SRSs using a plurality of SRS resources in a SRS resource set configured for SRS switching according to a first combination of downlink (DL) antenna ports and uplink (UL) antenna ports. The UE can turn off one or more of the DL antenna ports and the UL antenna ports for UE power saving purposes. The UE can then reconfigure the plurality of SRS resources in the SRS resource set for SRS switching according to a second combination of the DL antenna ports and the UL antenna ports. In response to a power saving message from a UE, a base station can generate SRS configuration information to configure a SRS resource set for SRS antenna switching based on active UL antenna ports at the UE and a combination of UL antenna ports, and send the SRS configuration information to the UE.

Description

TECHNICAL FIELD

[0001] The present application relates generally to wireless communication systems, and more specifically to sounding reference signal (SRS) antenna switching. BACKGROUND

[0002] Wireless mobile communication technology uses various standards and protocols to transmit data between base stations and wireless mobile devices. Wireless communication system standards and protocols can include the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) (e.g., 4G) or New Radio (NR) (e.g., 5G); the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard, which is commonly referred to as Worldwide Interoperability for Microwave Access (WiMAX); and the IEEE 802.11 standard for wireless local area networks (WLANs), which is commonly referred to as Wi-Fi. In a 3GPP radio access network (RAN) in an LTE system, base stations can comprise RAN nodes such as the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (also commonly denoted as evolved Node B, enhanced Node B, eNode B, or eNB) and / or a radio network controller (RNC) in the E-UTRAN, which communicate with wireless communication devices known as user equipment (UE). In a fifth generation (5G) wireless RAN, RAN nodes can comprise 5G nodes, NR nodes (also referred to as next generation Node Bs or g NodeBs (gNBs)).

[0003] A RAN uses a radio access technology (RAT) to communicate between RAN nodes and UEs. A RAN can comprise a global system for mobile communications (GSM), enhanced data rates for GSM evolution (EDGE) RAN (GERAN), universal terrestrial radio access network (UTRAN), and / or E-UTRAN, which provide access to communication services through a core network. Each RAN in a RAN operates according to a particular 3GPP RAT. For example, a GERAN implements GSM and / or EDGE RAT, a UTRAN implements universal mobile telecommunications system (UMTS) RAT or other 3GPP RAT, an E-UTRAN implements LTE RAT, and an NG-RAN implements 5G RAT. In certain deployments, an E-UTRAN can also implement 5G RAT.

[0004] The frequency bands of 5G NR can be split into two different frequency ranges. Frequency Range 1 (FR1) can include frequency bands that operate below 6 GHz, some of which can be used for previous standards, and can potentially be extended to cover a new spectrum product of 410- 7125 MHz. Frequency Range 2 (FR2) can include frequency bands that operate between 24.25 and 52.6 GHz. The bands in the millimeter wave (mmWave) range of FR2 can have a smaller range than the bands in FR1 but potentially a higher available bandwidth. The skilled person will recognize that these frequency ranges, provided by way of example, can vary over time or by region. BRIEF DESCRIPTION OF DRAWINGS

[0005] To easily identify discussions of any particular element or act, one or more of the highest three digits of a reference number refers to a drawing figure in which that element is first introduced.

[0006] Figure 1 An example of SRS antenna switching is shown in accordance with one embodiment.

[0007] Figure 2 An example of an exemplary UE power saving mode is shown in accordance with one embodiment.

[0008] Figure 3 An example of SRS antenna switching before and after a UE turns off downlink ports is shown in accordance with one embodiment.

[0009] Figure 4 An example of SRS antenna switching before and after a UE turns off downlink ports is shown in accordance with another embodiment.

[0010] Figure 5 An example of SRS antenna switching before and after a UE turns off downlink ports is shown in accordance with another embodiment.

[0011] Figure 6 An example of SRS antenna switching when one or more uplink ports are turned off is shown in accordance with one embodiment.

[0012] Figure 7 An example of SRS antenna switching when one or more uplink ports are turned off is shown in accordance with another embodiment.

[0013] Figure 8 A method for a UE to perform SRS switching is shown in accordance with one embodiment.

[0014] Figure 9 A method for a base station in a wireless network is shown in accordance with one embodiment.

[0015] Figure 10 A system is shown in accordance with one embodiment.

[0016] Figure 11 An exemplary service-based architecture 1100 is shown in accordance with certain embodiments.

[0017] Figure 12 A UE is shown in accordance with one embodiment.

[0018] Figure 13 A network node is shown in accordance with one embodiment.

[0019] Figure 14 A component is shown in accordance with one embodiment. DETAILED DESCRIPTION

[0020] A sounding reference signal (SRS) is a reference signal used to measure an uplink channel. A gNB or other network device can measure the uplink channel based on the SRS transmitted by a UE to determine the channel condition or quality of the uplink channel and schedule uplink resources. In some systems with channel reciprocity, the gNB can estimate the channel state information (CSI) of a downlink channel by using the CSI of the uplink channel obtained by measuring the uplink channel to schedule downlink resources. However, if the number of uplink antennas configured for the UE is less than the number of downlink antennas, the UE can need to switch multiple antennas to transmit multiple SRSs so that the gNB obtains the CSI of multiple downlink channels.

[0021] In Release 15 (Rel-15) NR or 5G networks, a UE can support antenna switching (e.g., also referred to as antenna port switching or port switching) to transmit SRS for downlink channel estimation. A UE can have different numbers of transmit (Tx) antenna ports (N_tx) and receive (Rx) antenna ports (N_rx), where N_tx can generally be lower than N_rx. To estimate downlink CSI based on uplink (UL) channel measurements, a gNB can trigger multiple SRS resources to construct a downlink (DL) channel. Certain systems support several types of antenna switching such as “xTyR,” where “T” represents Tx antenna ports or Tx chains, “R” represents Rx antenna ports or Rx chains, x = {1, 2, 4} (number of Tx antenna ports / chains), and y = {2, 4} (number of Rx antenna ports / chains). For example, for a 2T4R UE with 2 Tx chains and 4 Rx chains, the UE can transmit SRS twice (e.g., using antenna switching) on each of the 2 Tx chains to probe the channel for each of the 4 Rx chains. Similarly, for a 1T4R UE with 1 Tx chain and 4 Rx chains, the UE can transmit SRS four times (e.g., using antenna switching) on the single Tx chain to probe the channel for each of the 4 Rx chains. Those skilled in the art will recognize from the disclosure herein that other values of x and y can be used. For example, in Release 17 (Rel-17) NR or 5G networks, y can be increased to include 8.

[0022] Figure 1 An example of SRS antenna switching 100 for 1T4R is shown. In this example, a SRS resource set 102 (referred to as SRS resource set x) is configured for transmitting (e.g., broadcasting) SRS using multiple ports 104 (shown as port 0, port 1, port 2, and port 3). A SRS resource set can be configured for different types of uses, including codebook-based transmission, non-codebook-based transmission, transmission involving antenna switching, and / or transmission involving beam management, respectively. One SRS resource set can include one or more SRS resources. Figure 1 The illustrated SRS resource set 102 is configured for antenna switching use (use = “antenna switching” or use includes at least antenna switching) and includes a first SRS resource 106 for 1 port (referred to as SRS resource 0), a second SRS resource 108 for 1 port (referred to as SRS resource 1), a third SRS resource 110 for 1 port (referred to as SRS resource 2), and a fourth SRS resource 112 for 1 port (referred to as SRS resource 3).

[0023] For Figure 1For the illustrated 1T4R example, the UE transmits SRS four times on a single Tx chain using antenna switching to probe the channel for each of the 4 Rx chains. SRS resource 0 is used to transmit SRS on port 0, SRS resource 1 is used to transmit SRS on port 1, SRS resource 2 is used to transmit SRS on port 2, and SRS resource 3 is used to transmit SRS on port 3. After receiving the four SRS resources, the gNB can construct the DL channel.

[0024] In Release 16 (Rel-16) NR or 5G networks, with respect to UE power saving, a UE can turn off some UL antenna ports / DL antenna ports and report such behavior to the gNB. In certain embodiments, for example, a UE can send a preference to the gNB to use multiple UL and / or DL multiple-input multiple-output (MIMO) layers. For example, the UE can send a message to the gNB including a MaxMIMO-LayerPreference information element, such as:

[0025] MaxMIMO-LayerPreference-r16 ::= SEQUENCE {

[0026] reducedMaxMIMO-LayersFR1-r16 SEQUENCE {

[0027] reducedMIMO-LayersFR1-DL-r16 INTEGER (1..8),

[0028] reducedMIMO-LayersFR1-UL-r16 INTEGER (1..4)

[0029] } OPTIONAL,

[0030] reducedMaxMIMO-LayersFR2-r16 SEQUENCE {

[0031] reducedMIMO-LayersFR2-DL-r16 INTEGER (1..8),

[0032] reducedMIMO-LayersFR2-UL-r16 INTEGER (1..4)

[0033] } OPTIONAL

[0034] }

[0035] Figure 2An exemplary UE power saving mode 200 is shown in which the UE turns off one or more antenna ports, according to certain embodiments. In this example, the UE activates four ports 104 (referred to as port 0, port 1, port 2, and port 3). However, the UE can determine that the current conditions do not use or require four antenna ports. Accordingly, the UE reports to the gNB that the maximum number of MIMO layers is 2 (or indicates the preference for the gNB for a case of maximum 2 MIMO layers). In response, the gNB can signal to the UE to activate only 2 antenna ports 202 (shown as port 0 and new port 1). By using fewer antenna ports, the UE saves power.

[0036] To save power, the UE can turn off any number of antenna ports. However, after the UE turns off one or more antennas, the UE can need to determine how to transmit SRS for antenna switching. In certain embodiments, SRS antenna switching is reconfigured only when the UE turns off one or more DL antennas. In other embodiments, SRS antenna switching is reconfigured only when the UE turns off one or more UL antennas. In other embodiments, SRS antenna switching is reconfigured only when the UE turns off at least one DL antenna and at least one UL antenna. Turning off DL antennas, UL antennas, or both DL and UL antennas can result in y not being an integer multiple of x in a set of SRS resources of xTyR (e.g., 4T6R). Accordingly, certain embodiments reconfigure SRS antenna switching when y is not an integer multiple of x.

[0037] In certain embodiments, when turning off antenna ports, the UE can reconfigure SRS resources in a set of SRS resources for SRS switching without any further input from the gNB. In other embodiments, when turning off antenna ports, the gNB provides SRS configuration information to the UE for reconfiguring SRS resources in a set of SRS resources for SRS switching. SRS configuration (sometimes referred to as SRS resource configuration or SRS resource set configuration) can be indicated in a radio resource control (RRC) message (e.g., an RRC configuration message and an RRC reconfiguration message). The SRS configuration can indicate one or more resources included in a set of SRS resources. The resources can include time resources, frequency resources, spatial resources, etc. (e.g., slots, symbols, resource blocks, periodicity of time resources, beams, and / or spatial references). The SRS configuration can also include a mapping of SRS resources to antenna ports.

[0038] Closing one or more DL ports .

[0039] In one embodiment, if the UE turns off one or more DL ports such that xTyR becomes xTy’R (where y’ < y), the UE does not transmit SRS resources corresponding to y - y’ ports for SRS resource set antenna switching xTyR.

[0040] For example, Figure 3 An example of SRS antenna switching 300 for the SRS resource set 102 for 1T4R is shown, according to one embodiment, before and after the UE closes 2 DL ports. Figure 1 Figure 1 As described, Figure 3 The SRS resource set 102 shown is configured for antenna switching use (use = “antenna switching” or use includes at least antenna switching) and includes a first SRS resource 106 for 1 port (referred to as SRS resource 0), a second SRS resource 108 for 1 port (referred to as SRS resource 1), a third SRS resource 110 for 1 port (referred to as SRS resource 2), and a fourth SRS resource 112 for 1 port (referred to as SRS resource 3).

[0041] Before the UE closes 2 DL ports, the UE transmits SRS four times using antenna switching on a single Tx chain to probe the channel for each of the 4 Rx chains, as shown on the left side of arrow 302, with SRS resource 0 for transmitting SRS on port 0, SRS resource 1 for transmitting SRS on port 1, SRS resource 2 for transmitting SRS on port 2, and SRS resource 3 for transmitting SRS on port 3.

[0042] After the UE closes 2 DL ports (e.g., port 1 and port 3), the UE transmits SRS only on y-y’ ports (4-2 = 2 ports), as shown on the right side of arrow 302. Thus, as shown, Figure 3 When the SRS resource set 102 is triggered, the UE can transmit SRS using the first SRS resource 106 (SRS resource 0) and the second SRS resource 108 (SRS resource 1), but not the third SRS resource 110 (SRS resource 2) and the fourth SRS resource 112 (SRS resource 3), as shown. For illustrative purposes, solid lines for SRS resources indicate transmitted SRS (as shown in legend 304), and dashed lines for SRS resources indicate non-transmitted SRS (as shown in legend 306). If the non-transmitted SRS (i.e., SRS configured to be transmitted through SRS resource 2 and SRS resource 3 for 1T4R) collides with other uplink signals / channels, the other signals / channels can be transmitted.

[0043] In another embodiment, if the UE closes one or more DL ports such that xTyR becomes xTy’R (where y’ < y), the UE transmits all SRS resources for the SRS resource set antenna switching xTyR. The SRS resources (e.g., corresponding to y-y’ Rx chains) can be remapped to other active DL ports to achieve repetition gain.​

[0044] For example, Figure 4 This illustrates, according to one implementation, the situation before and after the UE shuts down two DL ports. Figure 1 The example shown is an SRS antenna switching 400 for SRS resource set 102 of 1T4R. (See also: Regarding...) Figure 1 The above, Figure 4 The SRS resource set 102 shown is configured for antenna switching purposes (purpose = "antenna switching" or the purpose includes at least antenna switching) and includes a first SRS resource 106 (referred to as SRS resource 0) for one port, a second SRS resource 108 (referred to as SRS resource 1) for one port, a third SRS resource 110 (referred to as SRS resource 2) for one port, and a fourth SRS resource 112 (referred to as SRS resource 3) for one port.

[0045] Before the UE closes the two DL ports, as shown to the left of arrow 402, the UE uses antenna switching to transmit SRS four times on a single Tx chain to probe the channel of each of the four Rx chains, where SRS resource 0 is used to transmit SRS on port 0, SRS resource 1 is used to transmit SRS on port 1, SRS resource 2 is used to transmit SRS on port 2, and SRS resource 3 is used to transmit SRS on port 3.

[0046] After the UE disables two DL ports (e.g., port 1 and port 3), as shown to the right of arrow 402, SRS resource 1 is remapped from port 1 to port 2, SRS resource 2 is remapped from port 2 to port 0, and SRS resource 3 is remapped from port 3 to port 2. Those skilled in the art will recognize from the disclosure herein that other remapping combinations are also possible. The UE uses antenna switching to transmit SRS four times on a single Tx chain to probe the channel of each of the four Rx chains, where SRS resource 0 is used to transmit SRS on port 0, SRS resource 1 is used to transmit SRS on port 2, SRS resource 2 is used to transmit SRS on port 0, and SRS resource 3 is used to transmit SRS on port 3.

[0047] If a duplicate SRS resource conflicts with another uplink signal, the other uplink signal can be transmitted. For example, in one implementation, when a duplicate SRS resource conflicts with another uplink signal, the UE discards the entire SRS resource set 102. However, in another implementation, only the duplicate SRS resource is discarded. For example, see... Figure 4To the right of the middle arrow 402, if SRS resource 0 is used to transmit SRS on port 0 and the repeated SRS resource 3 would collide with another uplink signal, the UE can determine not to use SRS resource 3 to transmit SRS on port 0.

[0048] In one embodiment, if the UE closes one or more DL ports such that xTyR becomes xTy’R (where y’ < y) instead of transmitting the set of SRS resources configured in xTyR, the UE only transmits the set of SRS resources when it is configured in xTy’R. In other words, after closing one or more DL ports, the UE waits until the gNB configures it with a new SRS configuration.

[0049] For example, Figure 5 Figures showing, according to one embodiment, before and after the UE closes 2 DL ports, Figure 1 The example of SRS antenna switching 500 for the set of SRS resources 102 for 1T4R shown. As with the example of SRS antenna switching 400 for the set of SRS resources 102 for 2T4R shown in Figure 4, the UE transmits SRS four times using antenna switching on a single Tx chain to probe the channel for each of the 4 Rx chains. Figure 1 As described, Figure 5 The set of SRS resources 102 shown is configured for antenna switching use (use = “antenna switching” or use includes at least antenna switching) and includes a first SRS resource 106 for 1 port (referred to as SRS resource 0), a second SRS resource 108 for 1 port (referred to as SRS resource 1), a third SRS resource 110 for 1 port (referred to as SRS resource 2), and a fourth SRS resource 112 for 1 port (referred to as SRS resource 3).

[0050] Before the UE closes 2 DL ports, as shown to the left of arrow 502, the UE transmits SRS four times using antenna switching on a single Tx chain to probe the channel for each of the 4 Rx chains, with SRS resource 0 used to transmit SRS on port 0, SRS resource 1 used to transmit SRS on port 1, SRS resource 2 used to transmit SRS on port 2, and SRS resource 3 used to transmit SRS on port 3.

[0051] After the UE closes 2 DL ports, as shown to the right of arrow 502, the UE does not transmit SRS on any port 104 using any of SRS resource 0, SRS resource 1, SRS resource 2, or SRS resource 3 of the set of SRS resources 102. In certain embodiments, the gNB can reconfigure the set of SRS resources 102 with a new SRS configuration based on xTy’R. The UE can then transmit SRS using the set of SRS resources 102 configured based on xTy’R.

[0052] Closing one or more UL ports .

[0053] In one implementation, if the UE closes one or more UL ports such that xTyR becomes x'TyR (where x' < x), the UE does not transmit the SRS resource set configured with xTyR regardless of whether the SRS resource set is triggered or not. In certain such implementations, the UE only transmits the SRS resource set for antenna switching when it is configured with x'TyR.

[0054] For example, Figure 6 An example of SRS antenna switching 600 when one or more UL ports are closed is shown, according to one implementation. In this example, a SRS resource set 602 configured for antenna switching use (use = "antenna switching" or use includes at least antenna switching) includes a first SRS resource 604 for 2 ports (referred to as SRS resource 0) and a second SRS resource 606 for 2 ports (referred to as SRS resource 1).

[0055] Before the UL ports are closed, the UE transmits SRS four times using antenna switching on one or more Tx chains to probe the channel for each of the 4 Rx chains, as shown on the left side of arrow 608. SRS resource 0 is used to transmit SRS on port 0 and port 1. SRS resource 1 is used to transmit SRS on port 2 and port 3.

[0056] After the UE closes 1 UL port, the UE does not transmit SRS on any port 104 using SRS resource 0 or SRS resource 1 of SRS resource set 602, as shown on the right side of arrow 608. In certain implementations, the gNB can reconfigure SRS resource set 602 with a new SRS configuration based on x'TyR. The UE can then transmit SRS using SRS resource set 602 configured based on x'TyR.

[0057] In one implementation, if the UE closes one or more UL ports such that xTyR becomes x'TyR (where x' < x), the UE repeatedly transmits the SRS resource set configured with xTyR until the number of SRS resources is greater than ceil(y / x'), where "ceil()" is a mathematical function that rounds a number up to the next largest whole or integer number. For each SRS resource, the UE can only need to transmit SRS from x' ports.

[0058] For example, Figure 7 An example of SRS antenna switching 700 when one or more UL ports are closed is shown, according to one implementation. Before the UL ports are closed, similar to Figure 6, the SRS resource set 602 includes a first SRS resource 604 for 2 ports (referred to as SRS resource 0) and a second SRS resource 606 for 2 ports (referred to as SRS resource 1). The UE transmits SRS four times on one or more Tx chains using antenna switching to probe the channels of each of the 4 Rx chains. SRS resource 0 is used to transmit SRS on ports 0 and port 1. SRS resource 1 is used to transmit SRS on ports 2 and port 3.

[0059] After the UE closes 1 UL port, as shown on the right side of arrow 702, the UE uses a first SRS resource 704 for 1 port (referred to as SRS resource 0) and a second SRS resource 706 for 1 port (referred to as SRS resource 1) to transmit SRS at two different transmission occasions of the SRS resource set 602. At the first transmission occasion (x), the UE uses SRS resource 0 on port 0 and SRS resource 1 on port 1 to transmit SRS. At the second transmission occasion (x + 1), the UE uses SRS resource 0 on port 2 and SRS resource 1 on port 3 to transmit SRS. Thus, even after closing one UL port, the UE continues to use antenna switching to transmit SRS four times to probe the channels of each of the 4 Rx chains.

[0060] Closing at least one UL port and at least one DL port .

[0061] In one embodiment, if the UE closes at least one UL port and at least one DL port such that xTyR becomes x'Ty'R (where x' < x and y' < y), the UE does not transmit the SRS resource set configured with xTyR, regardless of whether the SRS resource set is triggered. In some such embodiments, the UE may only transmit the SRS resource set for antenna switching when it is configured with x'Ty'R. After the gNB reconfigures the SRS resource set with a new SRS configuration based on x'Ty'R, the UE can use the SRS resource set configured with x'Ty'R to transmit SRS.

[0062] In another embodiment, if the UE closes at least one UL port and at least one DL port such that xTyR becomes x'Ty'R (where x' < x and y' < y), and if ceil(y' / x') is greater than ceil(y / x'), which means more SRS resources are needed, the UE repeatedly transmits the SRS resource set configured with xTyR until the number of SRS resources is greater than ceil(y' / x'), as described with respect to Figure 7 above. For each SRS resource, the UE may only need to transmit SRS from x' ports.

[0063] In another embodiment, if the UE turns off at least one UL port and at least one DL port such that xTyR becomes x'Ty'R (where x' < x and y' < y), and if ceil(y' / x') is less than ceil(y / x), which means some SRS resources are redundant, then the UE does not transmit the SRS resources corresponding to the y - y' ports for the SRS resource set antenna switch xTyR, as described with respect to Figure 3 above.

[0064] In another embodiment, if the UE turns off at least one UL port and at least one DL port such that xTyR becomes x'Ty'R (where x' < x and y' < y), and if ceil(y' / x') is less than ceil(y / x), which means some SRS resources are redundant, then the UE transmits all the SRS resources for the SRS resource set antenna switch xTyR and the SRS resources (e.g., corresponding to y - y' Rx chains) can be remapped to other active DL ports to achieve a repetition gain, as described with respect to Figure 4 above. For example, if the UE retreats from 2T4R to 1T2R, the UE can maintain the same SRS transmission behavior but with an updated port mapping. Additionally or in other embodiments, the UE can transmit SRS for a subset of ports. For example, if the UE does not need to transmit SRS from two ports, the UE transmits SRS from one port for each SRS resource.

[0065] In another embodiment, if the UE turns off at least one UL port and at least one DL port such that xTyR becomes x'Ty'R (where x' < x and y' < y), then the UE can set ceil(y' / x') = C and use antenna switching on SRS resource c, where c ∈ 0,..., C - 2, and x' Tx chains are used. The x' Tx chains are mapped to the downlink ports c·X', c·X'+1,..., X'+X'-1. Then, the UE can use antenna switching on SRS resource c - 1 and use (y' - (C - 1)x') Tx chains, which are mapped to the downlink ports c·X', c·X'+1,..., y' - 1, for c = C - 2. In one example, if the UE changes from 4T8R to 2T6R in SRS resource 1, the UE transmits 2 ports mapped to DL antennas 1 and 2. In SRS resource 2, the UE transmits 2 ports mapped to antennas 3 and 4. In this example, antennas 5 and 6 are not probed.

[0066] When y is not an integer multiple of x .

[0067] In one implementation, for an SRS resource set configured for antenna switching for xTyR, when y is not an integer multiple of x (e.g., 4T6R), the gNB can configure different SRS resources with different antenna ports in the resource set configured for antenna switching. In one example, for 4T6R, the gNB can configure a 4-port SRS and a 2-port SRS.

[0068] In another implementation, for an SRS resource set configured for antenna switching for xTyR, when y is not an integer multiple of x (e.g., 4T6R), the gNB may configure the same number of antenna ports for all SRS resources in the resource set configured for antenna switching. In some such implementations, the last SRS resource may be mapped to the remaining ports and / or some previous ports to achieve repetition gain. In one example, for 4T6R, the gNB may configure two 4-port SRS resources: SRS resource 1 is mapped to ports {1,2,3,4}, and SRS resource 2 is mapped to ports {5,6,1,2}.

[0069] UE reporting .

[0070] For some implementations disclosed herein, the UE may report whether it supports the new antenna configuration for x'Ty'R via UE capability message transmission. If the UE does not support the new antenna configuration x'Ty'R, the UE does not transmit the SRS resource set for antenna switching when the maximum layer number becomes associated with x'Ty'R.

[0071] In addition, or in other implementations, similar to reporting the maximum number of preferred UL and / or DL ​​layers, the UE may report its preferred SRS antenna switching configuration. In one example, for a UE previously configured with 2T8R, when the UE decides to disable one UL antenna and two DL antennas, the UE may report its preference for a 1T6R SRS antenna switching configuration. Such reports may be carried, for example, via Radio Resource Control (RRC) signaling, Media Access Control (MAC) control element (CE), or Physical Uplink Control Channel (PUCCH).

[0072] Figure 8This is a flowchart of a method 800 for a UE to perform SRS handover according to one embodiment. In block 802, the UE transmits one or more SRSs using multiple SRS resources in an SRS resource set configured for SRS handover, based on a first combination of downlink (DL) antenna ports and uplink (UL) antenna ports. In block 804, for UE power saving purposes, the UE disables one or more of the DL antenna ports and UL antenna ports. In block 806, the UE reconfigures multiple SRS resources in the SRS resource set for SRS handover based on a second combination of DL antenna ports and UL antenna ports.

[0073] In some embodiments of method 800, shutting down one or more of the DL antenna ports and UL antenna ports includes disabling at least one DL antenna port in a first combination of the DL antenna ports and UL antenna ports, and reconfiguring multiple SRS resources includes using a subset of the multiple SRS resources to transmit one or more SRSs based on a second combination of the DL antenna ports and UL antenna ports.

[0074] In some embodiments of method 800, disabling one or more of the DL antenna ports and UL antenna ports includes disabling at least one DL antenna port in a first combination of DL antenna ports and UL antenna ports, and reconfiguring the plurality of SRS resources includes remapping a subset of the plurality of SRS resources to one or more active DL ports in a second combination of DL antenna ports and UL antenna ports to provide repetitive gain for one or more SRSs. In some embodiments, method 800 further includes discarding all of the plurality of SRS resources in the SRS resource set in response to determining that a repetitive SRS resource on one or more active DL ports conflicts with another UL signal. In other embodiments, method 800 further includes discarding only the repetitive SRS resources in the SRS resource set in response to determining that a repetitive SRS resource on one or more active DL ports conflicts with another UL signal.

[0075] In some embodiments of method 800, shutting down one or more of the DL antenna ports and UL antenna ports includes disabling at least one DL antenna port in a first combination of the DL antenna ports and UL antenna ports, and reconfiguring multiple SRS resources includes waiting to use multiple SRS resources to transmit one or more SRSs until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of the DL antenna ports and UL antenna ports.

[0076] In some embodiments of method 800, shutting down one or more of the DL antenna ports and UL antenna ports includes disabling at least one UL antenna port in a first combination of the DL antenna ports and UL antenna ports, and reconfiguring multiple SRS resources includes waiting to use multiple SRS resources to transmit one or more SRSs until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of the DL antenna ports and UL antenna ports.

[0077] In some embodiments of method 800, shutting down one or more of the DL antenna ports and UL antenna ports includes disabling at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports, and reconfiguring multiple SRS resources includes repeatedly transmitting a set of SRS resources at different transmission times according to the first combination of DL antenna ports and UL antenna ports until the number of SRS resources transmitted is greater than the ratio of active DL antenna ports to active UL antenna ports.

[0078] In some embodiments of method 800, shutting down one or more of the DL antenna ports and UL antenna ports includes disabling at least one DL antenna port and at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports, and reconfiguring multiple SRS resources includes waiting to use the multiple SRS resources to transmit one or more SRSs, regardless of whether the multiple SRS resources are triggered, until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of DL antenna ports and UL antenna ports.

[0079] In certain embodiments of method 800, turning off one or more of the DL antenna ports and UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), where corresponding to the first combination of DL antenna ports and UL antenna ports, x represents a first number of transmit (T) chains and y represents a first number of receive (R) chains, and where corresponding to the second combination of DL antenna ports and UL antenna ports, x' represents a second number of T chains and y' represents a second number of R chains. If ceil(y' / x') is greater than ceil(y / x), such that more SRS resources will be used, the UE repeatedly transmits the set of SRS resources configured with xTyR until the number of SRS resources is greater than ceil(y' / x'). If ceil(y' / x') is less than ceil(y / x), such that some SRS resources are redundant, the UE does not transmit the SRS resources corresponding to the y - y' ports for the SRS resource set antenna switch xTyR, or the UE transmits all of the SRS resources for the SRS resource set antenna switch xTyR and the SRS resources corresponding to the y - y' receive chains are remapped to other active DL ports to achieve a diversity gain. If ceil(y' / x') is the same as ceil(y / x), the UE changes the port mapping and the transmitted ports for each SRS resource and transmits the entire SRS resource set.

[0080] In certain embodiments of method 800, turning off one or more of the DL antenna ports and UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), where corresponding to the first combination of DL antenna ports and UL antenna ports, x represents a first number of transmit (T) chains and y represents a first number of receive (R) chains, where corresponding to the second combination of DL antenna ports and UL antenna ports, x' represents a second number of T chains and y' represents a second number of R chains, and where ceil(y' / x') = C. The UE uses antenna switching on SRS resource c for c ∈ 0,..., C - 2 and uses x' transmit chains, where the x' transmit chains are mapped to downlink ports c·X', c·X' + 1,..., c·X' + X' - 1. The UE uses antenna switching on SRS resource c - 1 and uses (y' - (C - 1)x') transmit chains, which are mapped to downlink ports c·X', c·X' + 1,..., y' - 1, for c = C - 2.

[0081] Figure 9This is a flowchart of method 900 for a base station (e.g., gNB or other network device) in a wireless network according to one embodiment. In block 902, the base station receives a power-saving message from the user equipment indicating a preference for reducing the number of MIMO layers. In block 904, in response to the power-saving message, the base station generates SRS configuration information to configure the SRS resource set for SRS antenna switching based on the combination of active downlink (DL) antenna ports and uplink (UL) antenna ports at the UE. In block 906, the base station sends the SRS configuration information to the UE.

[0082] Some embodiments of method 900 also include determining that the number of active DL antenna ports is not an integer multiple of the number of active UL antenna ports, and configuring different SRS resources with different antenna ports in an SRS resource set configured with SRS antenna switching.

[0083] Some embodiments of method 900 also include determining that the number of active DL antenna ports is not an integer multiple of the number of active UL antenna ports, and configuring the same number of antenna ports for all SRS resources in an SRS resource set configured with SRS antenna switching.

[0084] Some implementations of method 900 also include mapping the last SRS resource in the SRS resource set to a previously used port to achieve repetition gain.

[0085] Figure 10 An exemplary architecture of a system 1000 for a network according to various implementations is shown. The following description is provided for an example system 1000 operating in combination with LTE system standards and 5G or NR system standards provided by 3GPP technical specifications. However, the exemplary implementations are not limited in this respect, and the implementations can be applied to other networks that benefit from the principles described herein, such as future 3GPP systems (e.g., sixth generation (6G)) systems, IEEE 802.16 protocols (e.g., WMAN, WiMAX, etc.), etc.

[0086] like Figure 10As shown, system 1000 includes UE 1002 and UE 1004. In this example, UE 1002 and UE 1004 are shown as smartphones (e.g., handheld touchscreen mobile computing devices that can connect to one or more cellular networks), but may also include any mobile or non-mobile computing device, such as consumer electronics devices, mobile phones, smartphones, feature phones, tablets, wearable computing devices, personal digital assistants (PDAs), pagers, wireless handheld devices, desktop computers, laptops, in-vehicle infotainment (IVI), in-vehicle entertainment (ICE) devices, instrument clusters (ICs), head-up displays (HUDs), onboard diagnostics (OBD) devices, dashtop mobile equipment (DME), mobile data terminals (MDTs), electronic engine management systems (EEMS), electronic / engine electronic control units (ECUs), electronic / engine electronic control modules (ECMs), embedded systems, microcontrollers, control modules, engine management systems (EMS), connected or “smart” appliances, MTC devices, M2M, IoT devices, etc.

[0087] In some implementations, UE 1002 and / or UE 1004 may be IoT UEs, which may include a network access layer designed to utilize low-power IoT applications with short-lived UE connections. IoT UEs may utilize technologies such as M2M or MTC to exchange data with MTC servers or devices via PLMN, ProSe or D2D communication, sensor networks, or IoT networks. M2M or MTC data exchange may be machine-initiated data exchange. An IoT network describes interconnected IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure) with short-lived connections. IoT UEs may execute background applications (e.g., keeping track of activity messages, status updates, etc.) to facilitate connectivity within the IoT network.

[0088] UE 1002 and UE 1004 can be configured to connect to an access node or radio access node (shown as (R)AN1016), for example, through communication coupling. In implementations, (R)AN 1016 can be an NG RAN or SG RAN, E-UTRAN, or a legacy RAN such as UTRAN or GERAN. As used herein, the term "NG RAN," etc., can refer to (R)AN 1016 operating in an NR or SG system, and the term "E-UTRAN," etc., can refer to (R)AN 1016 operating in an LTE or 4G system. UE 1002 and UE 1004 utilize connections (or channels) (shown as connection 1006 and connection 1008, respectively), each connection including a physical communication interface or layer (discussed in further detail below).

[0089] In this example, connections 1006 and 1008 are air interfaces for communication coupling and are compatible with cellular communication protocols such as GSM, CDMA, PTT, POC, UMTS, 3GPP LTE, SG, NR, and / or any other communication protocols discussed herein. In an implementation, UE 1002 and UE 1004 may also exchange communication data directly via ProSe interface 1010. ProSe interface 1010 may alternatively be referred to as sidelink (SL) interface 110 and may include one or more logical channels, including but not limited to PSCCH, PSSCH, PSDCH, and PSBCH.

[0090] UE 1004 is shown configured to access AP 1012 (also known as a "WLAN node", "WLAN", "WLAN terminal", "WT", etc.) via connection 1014. Connection 1014 may include a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, where AP 1012 will include Wireless Fibre. Router. In this example, AP 1012 is connected to the Internet but not to the core network of the wireless system (described in further detail below). In various implementations, UE 1004, (R)AN 1016, and AP 1012 can be configured to utilize LWA operation and / or LWIP operation. LWA operation may involve UE 1004 in RRC_CONNECTED configured by RAN node 1018 or RAN node 1020 to utilize the radio resources of LTE and WLAN. LWIP operation may involve UE 1004 using WLAN radio resources (e.g., connection 1014) via IPsec protocol tunneling to authenticate and encrypt packets (e.g., IP packets) transmitted through connection 1014. IPsec tunneling may include encapsulating the entire original IP packet and adding a new packet header to protect the original header of the IP packet.

[0091] (R)AN 1016 may include one or more AN nodes, such as RAN node 1018 and RAN node 1020, that implement connection 1006 and connection 1008. As used herein, the terms “access node,” “access point,” etc., can describe equipment that provides radio baseband functionality for data and / or voice connections between the network and one or more users. These access nodes may be referred to as BS, gNB, RAN node, eNB, NodeB, RSU, TRxP, or TRP, etc., and may include ground stations (e.g., terrestrial access points) or satellite stations that provide coverage within a geographic area (e.g., a cell). As used herein, the terms “NG RAN node,” etc., can refer to a RAN node (e.g., gNB) operating in an NR or SG system, while the terms “E-UT RAN node,” etc., can refer to a RAN node (e.g., eNB) operating in an LTE or 4G system 1000. According to various implementation schemes, RAN node 1018 or RAN node 1020 may be implemented as one or more of dedicated physical devices such as macro cell base stations and / or low-power (LP) base stations for providing smaller coverage areas, smaller user capacity or higher bandwidth compared to macro cells.

[0092] In some implementations, all or part of RAN node 1018 or RAN node 1020 may be implemented as one or more software entities running on a server computer as part of a virtual network, which may be referred to as CRAN and / or Virtual Baseband Unit Pool (vBBUP). In these implementations, CRAN or vBBUP may implement RAN function partitioning, such as PDCP partitioning, where the RRC and PDCP layers are operated by CRAN / vBBUP, while other L2 protocol entities are operated by individual RAN nodes (e.g., RAN node 1018 or RAN node 1020); MAC / PHY partitioning, where the RRC, PDCP, RLC, and MAC layers are operated by CRAN / vBBUP, and the PHY layer is operated by individual RAN nodes (e.g., RAN node 1018 or RAN node 1020); or “lower PHY” partitioning, where the upper portion of the RRC, PDCP, RLC, MAC, and PHY layers is operated by CRAN / vBBUP, and the lower portion of the PHY layer is operated by individual RAN nodes. This virtualization framework allows idle processor cores of RAN node 1018 or RAN node 1020 to execute other virtualized applications. In some specific implementations, a single RAN node can be represented via a separate F1 interface ( Figure 10(Not shown) A separate gNB-DU connected to the gNB-CU. In these specific implementations, the gNB-DU may include one or more remote radio head units or RFEMs, and the gNB-CU may be operated by a server (not shown) located in (R)AN 1016 or by a server pool in a manner similar to CRAN / vBBUP. Alternatively, one or more of RAN nodes 1018 or RAN nodes 1020 may be next-generation eNBs (ng-eNBs), which are RAN nodes that provide E-UTRA user plane and control plane protocol terminals to UE 1002 and UE 1004 and are connected to the SGC via an NG interface (discussed below). In V2X scenarios, one or more of RAN nodes 1018 or RAN nodes 1020 may be RSUs or act as RSUs.

[0093] The term "roadside unit" or "RSU" can refer to any traffic infrastructure entity used for V2X communication. An RSU can be implemented in or by a suitable RAN node or a stationary (or relatively stationary) UE, wherein an RSU implemented in or by a UE can be referred to as a "UE-type RSU," an RSU implemented in or by an eNB can be referred to as an "eNB-type RSU," an RSU implemented in or by a gNB can be referred to as a "gNB-type RSU," and so on. In one example, an RSU is a computing device coupled to radio frequency circuitry located on the roadside that provides connectivity support to passing vehicle UEs (vUEs). An RSU may also include internal data storage circuitry for storing intersection map geometry, traffic statistics, media, and applications / software for sensing and controlling ongoing vehicle and pedestrian traffic. An RSU can operate on the 5.9 GHz Direct Near Range Communication (DSRC) band to provide extremely low-latency communication required for high-speed events, such as collision avoidance and traffic warnings. Alternatively or in addition to this, the RSU may operate on a cellular V2X band to provide the aforementioned low-latency communications and other cellular communication services. Alternatively or in addition to this, the RSU may operate as a Wi-Fi hotspot (2.4 GHz band) and / or provide connectivity to one or more cellular networks to provide uplink and downlink communications. Some or all of the computing device and the RSU's radio frequency circuitry may be packaged in a weather-resistant package suitable for outdoor installation and may include a network interface controller to provide wired connectivity (e.g., Ethernet) to traffic signal controllers and / or backhaul networks.

[0094] RAN node 1018 and / or RAN node 1020 may terminate the air interface protocol and may be the first point of contact for UE 1002 and UE 1004. In some implementations, RAN node 1018 and / or RAN node 1020 may perform various logical functions of (R)AN 1016, including but not limited to the functions of the Radio Network Controller (RNC), such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management.

[0095] In the implementation, UE 1002 and UE 1004 may be configured to communicate with each other or with RAN node 1018 and / or RAN node 1020 on a multi-carrier communication channel using OFDM communication signals according to various communication technologies, such as, but not limited to, OFDMA communication technology (e.g., for downlink communication) or SC-FDMA communication technology (e.g., for uplink and ProSe or sidelink communication), although the scope of the implementation is not limited in this respect. The OFDM signal may include multiple orthogonal subcarriers.

[0096] In some implementations, the downlink resource grid can be used for downlink transmissions from RAN node 1018 and / or RAN node 1020 to UE 1002 and UE 1004, while uplink transmissions can utilize similar techniques. The grid can be a time-frequency grid, referred to as a resource grid or time-frequency resource grid, which represents the physical resources in the downlink within each time slot. This time-frequency plane representation is common practice for OFDM systems, making radio resource allocation intuitive. Each column and row of the resource grid corresponds to an OFDM symbol and an OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to a time slot in a radio frame. The smallest time-frequency unit in the resource grid is represented as a resource element. Each resource grid comprises multiple resource blocks that describe the mapping of certain physical channels to resource elements. Each resource block comprises a set of resource elements; in the frequency domain, this can represent the minimum amount of resources currently available for allocation. Such resource blocks are used to transmit several different physical downlink channels.

[0097] According to various implementations, UE 1002 and UE 1004, as well as RAN node 1018 and / or RAN node 1020, transmit data (e.g., transmit and receive data) through licensed media (also referred to as “licensed spectrum” and / or “licensed band”) and unlicensed shared media (also referred to as “unlicensed spectrum” and / or “unlicensed band”). Licensed spectrum may include channels operating in the frequency range of approximately 400 MHz to approximately 3.8 GHz, while unlicensed spectrum may include a 5 GHz band.

[0098] To operate in unlicensed spectrum, UEs 1002 and 1004, along with RAN node 1018 or RAN node 1020, may use LAA, eLAA, and / or feLAA mechanisms. In these specific implementations, UEs 1002 and 1004, along with RAN node 1018 or RAN node 1020, may perform one or more known media sensing and / or carrier sensing operations to determine whether one or more channels in the unlicensed spectrum are unavailable or otherwise occupied before transmission in the unlicensed spectrum. Media / carrier sensing operations may be performed according to a Listen-After-Speak (LBT) protocol.

[0099] LBT is a mechanism that equipment (e.g., UE 1002 and UE 1004, RAN node 1018 or RAN node 1020, etc.) uses to sense a medium (e.g., a channel or carrier frequency) and transmit when the medium is sensed to be idle (or when a specific channel in the medium is sensed to be unoccupied). The medium sensing operation may include CCA, which utilizes at least ED to determine the presence of other signals on the channel in order to determine whether the channel is occupied or idle. This LBT mechanism allows cellular / LAA networks to coexist with existing systems in unlicensed spectrum and with other LAA networks. ED may include sensing RF energy in the intended transmission band over a period of time and comparing the sensed RF energy with a predefined or configured threshold.

[0100] Typically, existing systems in the 5GHz band are WLANs based on IEEE 802.11 technology. WLANs employ a contention-based channel access mechanism known as CSMA / CA. Here, when a WLAN node (e.g., a mobile station (MS) such as UE 1002, AP1012, etc.) intends to transmit, the WLAN node can first perform CCA before transmitting. Additionally, in cases where more than one WLAN node senses the channel as idle and transmits simultaneously, a backoff mechanism is used to avoid collisions. This backoff mechanism can be a counter randomly introduced within the CWS, which increases exponentially upon collision and resets to a minimum value upon successful transmission. The LBT mechanism designed for LAA is somewhat similar to WLAN's CSMA / CA. In some specific implementations, the LBT process for DL ​​or UL transmission bursts (including PDSCH or PUSCH transmissions) can have a variable-length LAA contention window between slots X and Y, where X and Y are the minimum and maximum values ​​of the LAA's CWS. In one example, the minimum CWS for LAA transmission can be 9 microseconds (μs); however, the size of the CWS and MCOT (e.g., transmission burst) can be based on government regulatory requirements.

[0101] The LAA mechanism is built upon the CA technology of LTE-Advanced systems. In CA, each aggregated carrier is called a CC. A CC can have a bandwidth of 1.4, 3, 5, 10, 15, or 20 MHz, and a maximum of five CCs can be aggregated, thus the maximum aggregated bandwidth is 100 MHz. In FDD systems, the number of aggregated carriers can differ for DL ​​and UL, where the number of UL CCs is equal to or less than the number of DL component carriers. In some cases, individual CCs can have different bandwidths than the other CCs. In TDD systems, the number of CCs and the bandwidth of each CC are usually the same for DL ​​and UL.

[0102] The CA also includes individual serving cells to provide individual CCs. The coverage of serving cells can differ, for example, because CCs on different frequency bands will experience different path losses. The primary serving cell, or PCell, provides PCCs for both UL and DL and handles activities related to RRC and NAS. Other serving cells are called SCells, and each SCell provides individual SCCs for both UL and DL. SCCs can be added and removed as needed, while changing the PCC may require UE 1002 to undergo a handover. In LAA, eLAA, and feLAA, some or all of the SCells can operate in unlicensed spectrum (referred to as "LAA SCells"), and LAA SCells are assisted by PCells operating in licensed spectrum. When a UE is configured to have more than one LAA SCell, the UE can receive UL grants on the configured LAA SCells, indicating different PUSCH start positions within the same subframe.

[0103] The PDSCH carries user data and higher-layer signaling to UE 1002 and UE 1004. Among other information, the PDCCH carries information about the transmission format and resource allocation related to the PDSCH channel. It also informs UE 1002 and UE 1004 about the transmission format, resource allocation, and HARQ information related to the uplink shared channel. Typically, downlink scheduling (allocating control and shared channel resource blocks to UE 1004 within the cell) can be performed at either RAN node 1018 or RAN node 1020 based on channel quality information fed back from either UE 1002 or UE 1004. Downlink resource allocation information can be transmitted on the PDCCH used (e.g., allocated to) each of UE 1002 and UE 1004.

[0104] PDCCH uses CCEs to transmit control information. Before being mapped to resource elements, the complex-valued symbols of the PDCCH can first be organized into quadruplets, which can then be arranged using a sub-block interleaver for rate matching. One or more of these CCEs can be used to transmit each PDCCH, where each CCE can correspond to nine sets, called REGs, each with four physical resource elements. Four Quadrature Phase Shift Keying (QPSK) symbols can be mapped to each REG. Depending on the DCI size and channel conditions, one or more CCEs can be used to transmit the PDCCH. Four or more different PDCCH formats defined in LTE with different numbers of CCEs (e.g., aggregation level, L = 1, 2, 4, or 8) can exist.

[0105] Some implementations may use the concept of resource allocation for control channel information, which is an extension of the above concept. For example, some implementations may utilize EPDCCH, which uses PDSCH resources for control information transmission. One or more ECCEs may be used to transmit EPDCCH. Similarly, each ECCE may correspond to a set of nine, each consisting of four physical resource elements, called EREG. In some cases, an ECCE may have a different number of EREGs.

[0106] RAN node 1018 or RAN node 1020 may be configured to communicate with each other via interface 1022. In implementations where system 1000 is an LTE system (e.g., when CN 1030 is an EPC), interface 1022 may be an X2 interface. The X2 interface may be defined between two or more RAN nodes connected to the EPC (e.g., two or more eNBs, etc.), and / or between two eNBs connected to the EPC. In some specific implementations, the X2 interface may include an X2 user plane interface (X2-U) and an X2 control plane interface (X2-C). X2-U may provide flow control mechanisms for user packets transmitted via the X2 interface and may be used to transmit information about the delivery of user data between eNBs. For example, X2-U may provide specific sequence number information about user data transmitted from a MeNB to a SeNB; information about the successful in-order delivery of PDCP PDUs from the SeNB to UE 1002 for user data; information about PDCP PDUs not delivered to UE 1002; information about the current minimum expected buffer size at the SeNB for transmitting user data to the UE; and so on. The X2-C provides LTE intra-eNB access mobility functions, including context transmission from the source eNB to the destination eNB, user plane transmission control, load management functions, and inter-cell interference coordination functions.

[0107] In implementations where system 1000 is an SG or NR system (e.g., when CN 1030 is an SGC), interface 1022 may be an Xn interface. The Xn interface is defined between two or more RAN nodes connected to the SGC (e.g., two or more gNBs, etc.), between a RAN node 1018 (e.g., a gNB) connected to the SGC and an eNB, and / or between two eNBs connected to the 5GC (e.g., CN 1030). In some specific implementations, the Xn interface may include an Xn user plane (Xn-U) interface and an Xn control plane (Xn-C) interface. Xn-U provides non-guaranteed delivery of user plane PDUs and supports / provides data forwarding and flow control functions. Xn-C provides management and error handling functions for managing the functionality of the Xn-C interface; mobility support for UE 1002 in connected modes (e.g., CM-CONNECTED) includes functions for managing UE mobility in connected modes between one or more RAN nodes 1018 or RAN nodes 1020. Mobility support may include context transfer from the old (source) serving RAN node 1018 to the new (target) serving RAN node 1020, and control of the user plane tunnel between the old (source) serving RAN node 1018 and the new (target) serving RAN node 1020. The Xn-U protocol stack may include a transport network layer built on top of the Internet Protocol (IP) transport layer, and a GTP-U layer on top of the UDP and / or IP layers for carrying user plane PDUs. The Xn-C protocol stack may include an application layer signaling protocol (referred to as the Xn Application Protocol (Xn-AP)) and a transport network layer built on top of SCTP. SCTP may be on top of the IP layer and provides guaranteed delivery of application layer messages. In the transport IP layer, point-to-point transmission is used to deliver signaling PDUs. In other specific implementations, the Xn-U protocol stack and / or the Xn-C protocol stack may be the same as or similar to the user plane and / or control plane protocol stacks shown and described herein.

[0108] (R)AN 1016 is shown as communicatively coupled to the core network, in which embodiment, communicatively coupled to CN1030. CN1030 may include one or more network elements 1032 configured to provide various data and telecommunications services to customers / subscribers (e.g., users of UE 1002 and UE 1004) connected to CN1030 via (R)AN 1016. Components of CN1030 may be implemented in a single physical node or in separate physical nodes, including components for reading and executing instructions from machine-readable or computer-readable media (e.g., non-transitory machine-readable storage media). In some embodiments, NFV may be used to virtualize any or all of the aforementioned network node functions via executable instructions stored in one or more computer-readable storage media (described in further detail below). A logical instance of CN1030 may be referred to as a network slice, and a logical instance of a portion of CN1030 may be referred to as a network subslice. NFV architectures and infrastructure can be used to virtualize one or more network functions onto physical resources that include a combination of industry-standard server hardware, storage hardware, or switches (or alternatively, proprietary hardware). In other words, NFV systems can be used to perform virtual or reconfigurable concrete implementations of one or more EPC components / functions.

[0109] Generally, application server 1034 can be a component that provides IP bearer resources for use with the core network (e.g., UMTS PS domain, LTE PS data service, etc.). Application server 1034 can also be configured to support one or more communication services (e.g., VoIP sessions, PTT sessions, group communication sessions, social networking services, etc.) for UE 1002 and UE 1004 via EPC. Application server 1034 can communicate with CN 1030 through IP communication interface 1036.

[0110] In this implementation, CN 1030 may be an SGC, and (R)AN 116 may be connected to CN 1030 via NG interface 1024. In this implementation, NG interface 1024 may be divided into two parts: an NG user plane (NG-U) interface 1026, which carries traffic data between RAN node 1018 or RAN node 1020 and the UPF; and an S1 control plane (NG-C) interface 1028, which is the signaling interface between RAN node 1018 or RAN node 1020 and the AMF.

[0111] In one implementation, CN 1030 may be an SG CN, while in other implementations, CN 1030 may be an EPC. When CN 1030 is an EPC, (R)AN 116 may be connected to CN 1030 via S1 interface 1024. In one implementation, S1 interface 1024 may be divided into two parts: an S1 user plane (S1-U) interface 1026, which carries traffic data between RAN node 1018 or RAN node 1020 and the S-GW; and an S1-MME interface 1028, which is the signaling interface between RAN node 1018 or RAN node 1020 and the MME.

[0112] Exemplary system architecture

[0113] In some implementations, the 5G system architecture supports data connectivity and services, enabling deployment using technologies such as network function virtualization and software-defined networking. The 5G system architecture can leverage service-based interactions between control plane network functions. Separating user plane functions from control plane functions allows for independent scalability, evolution, and flexible deployment (e.g., centralized or distributed (remote) locations). Modular function design allows for function reuse and enables flexible and efficient network slicing. Network functions and their network function services can interact directly or indirectly with another NF and its network function services via a service communication broker. Another intermediate function helps route control plane messages. This architecture minimizes dependencies between the AN and CN. The architecture may include an aggregated core network with a common AN-CN interface integrating different access types (e.g., 3GPP access and non-3GPP access). The architecture also supports a unified authentication framework, stateless NFs that decouple compute and storage resources, capability exposure, concurrent access to local and centralized services (to support low-latency services and access to local data networks, with user plane functions deployed near the AN), and / or roaming in the visited PLMN using both home-routed traffic and local breakout traffic.

[0114] A 5G architecture can be defined as service-based, and interactions between network functions can include service-based representations, where a network function within the control plane (e.g., an AMF) enables other authorized network functions to access its services. Service-based representations can also include point-to-point reference points. Reference point representations can also be used to illustrate interactions between NF services within network functions described by point-to-point reference points (e.g., N11) between any two network functions (e.g., AMF and SMF).

[0115] Figure 11A service-based architecture 1100 in 5GS according to one implementation is shown. As described in 3GPP TS23.501, the service-based architecture 1100 includes NFs such as NSSF 1102, NEF 1104, NRF 1106, PCF 1108, UDM 1110, AUSF 1112, AMF 1114, and SMF 1116 for communicating with UE 1120, (R)AN 1122, UPF 1124, and DN 1126. NFs and NF services can communicate directly (referred to as direct communication) or indirectly via SCP 1118 (referred to as indirect communication). Figure 11 It also shows the corresponding service-based interfaces including Nutm, Naf, Nudm, Npcf, Nsmf, Nnrf, Namf, Nnef, Nnssf, and Nausf, as well as reference points N1, N2, N3, N4, and N6. The following describes the... Figure 11 Some exemplary functions provided by NF are shown in the figure.

[0116] NSSF 1102 supports functions such as: selecting the set of network slice instances serving the UE; determining the allowed NSSAIs and, if necessary, the mapping to subscribed S-NSSAIs; determining the configured NSSAIs and, if necessary, the mapping to subscribed S-NSSAIs; and / or determining the set of AMFs to be used to serve the UE, or, based on the configuration, possibly by querying the NRF to determine a list of candidate AMFs.

[0117] The NEF 1104 supports the exposure of capabilities and events. NF capabilities and events can be securely exposed by the NEF 1104 (e.g., for third-party, application functions, and / or edge computing). The NEF 1104 can use a standardized interface (Nudr) to the UDR to store / retrieve information as structured data. The NEF 1104 can also securely provide information from external applications to the 3GPP network and can provide application functions to securely provide information to the 3GPP network (e.g., anticipated UE behavior, 5GLAN group information, and service-specific information), where the NEF 1104 can authenticate and authorize and help restrict application functions. The NEF 1104 can provide internal-external information translation by translating information exchanged with the AF and information exchanged with internal network functions. For example, the NEF 1104 translates between the AF service identifier and internal 5G core information (such as DNN and S-NSSAI). The NEF 1104 can handle the masking of network and user-sensitive information to external AFs according to network policies. The NEF 1104 can receive information from other network functions (based on their exposure capabilities) and uses a standardized interface with the UDR to store the received information as structured data. The stored information can be accessed by the NEF 1104 and re-exposed to other network and application functions, and used for other purposes such as analysis. For external exposure of services related to a specific UE, the NEF 1104 can reside in the HPLMN. Depending on the operator agreement, the NEF 1104 in the HPLMN can have an interface with the NF in the VPLMN. When the UE is able to switch between EPC and 5GC, SCEF+NEF can be used for service exposure.

[0118] NRF 1106 supports service discovery by receiving NF discovery requests from NF instances or SCPs and providing information about discovered NF instances to the NF instances or SCPs. NRF 1106 also supports P-CSCF discovery (a special case of SMF discovery of AFs), maintaining NF profiles of available NF instances and their supported services, and / or notifying subscribed NF service consumers or SCPs of newly registered / updated / deregistered NF instances along with their NF services. In the context of network slicing, multiple NRFs can be deployed at different levels depending on the network implementation, such as PLMN level (NRFs configured with information about the entire PLMN), shared slice level (NRFs configured with information about the network slice set), and / or slice-specific level (NRFs configured with information about the S-NSSAI). In the context of roaming, multiple NRFs can be deployed in different networks, where the NRF in the visited PLMN (referred to as vNRF) is configured with information about the visited PLMN, and the NRF in the home PLMN (referred to as hNRF) is configured with information about the home PLMN, referenced by the vNRF via the N27 interface.

[0119] PCF 1108 supports a unified policy framework for managing network behavior. PCF 1108 provides policy rules for control plane functions to enforce them. PCF 1108 accesses subscription information related to policy decisions in the Unified Data Repository (UDR). PCF 1108 can access the UDR located in the same PLMN as PCF.

[0120] The UDM 1110 supports the generation of 3GPP AKA authentication credentials, user identification processing (e.g., storage and management of SUPI for each subscriber in a 5G system), de-hiding of privacy-preserving subscription identifiers (SUCI), access authorization based on subscription data (e.g., roaming restrictions), UE service NF registration management (e.g., storing AMF for UE storage services, storing SMF for UE PDU sessions), service / session continuity (e.g., maintaining SMF / DNN allocation for ongoing sessions), MT-SMS delivery, lawful interception functionality (especially in outbound roaming scenarios where the UDM is the only contact point of the LI), subscription management, SMS management, 5GLAN group management processing, and / or external parameter configuration (expected UE behavior parameters or network configuration parameters). To provide these functions, the UDM 1110 uses subscription data (including authentication data) that can be stored in the UDR. In this case, the UDM implements application logic and may not require internal user data storage, and several different UDMs can provide services to the same user in different transactions. The UDM 1110 can reside in the HPLMN of its subscribers and can access information from the UDR located in the same PLMN.

[0121] AF 1128 interacts with the core network to provide services such as: application-driven traffic routing; access to NEF 1104; interaction with policy frameworks used for policy control; and / or interaction between IMS and 5GC. Based on operator deployment, application functions trusted by the operator may be allowed to interact directly with relevant network functions. Application functions that the operator does not allow direct access to network functions may interact with relevant network functions via an external exposure framework through NEF 1104.

[0122] AUSF 1112 supports authentication for 3GPP access and untrusted non-3GPP access. AUSF 1112 also provides support for network slicing-specific authentication and authorization.

[0123] AMF 1114 supports the termination of the RAN CP interface (N2), the termination of the NAS (N1) for NAS encryption and integrity protection, registration management, connection management, reachability management, mobility management, lawful interception (for AMF events and interfaces to the LI system), transmission of SM messages between the UE and SMF, transparent proxy for routing SM messages, access authentication, access authorization, transmission of SMS messages between the UE and SMSF, SEAF, location service management for regulated services, transmission of location service messages between the UE and LMF and between the RAN and LMF, EPS bearer ID allocation for interoperability with EPS, UE mobility event notification, control plane CIoT 5GS optimization, user plane CIoT 5GS optimization, configuration of external parameters (expected UE behavior parameters or network configuration parameters) and / or network slice-specific authentication and authorization. Some or all of the AMF functions can be supported in a single instance of AMF 1114. Regardless of the number of network functions, in some implementations, only one NAS interface instance per access network between the UE and the CN terminates with one of the network functions that implements at least NAS security and mobility management. AMF 1114 may also include policy-related functions.

[0124] In addition to the functions described above, AMF 1114 may also include the following functions supporting non-3GPP access networks: support for the N2 interface with N3IWF / TNGF, on which some information (e.g., 3GPP cell identifier) ​​and procedures (e.g., handover-related) defined on 3GPP access may not be applicable, and non-3GPP access-specific information not applicable to 3GPP access can be applied; support for NAS signaling by UE via N3IWF / TNGF, where some procedures supported by NAS signaling on 3GPP access may not be applicable to untrusted non-3GPP (e.g., paging) access; support for authentication of UEs connected via N3IWF / TNGF; management of mobility, authentication, and separate security context states for UEs connected via non-3GPP access or simultaneously via 3GPP access or non-3GPP access; support for effective coordination of RM management contexts on both 3GPP and non-3GPP access; and / or support for dedicated CM management contexts for UEs connecting via non-3GPP access. Support for all of the above functions may not be required in network slicing instances.

[0125] SMF 1116 supports session management (e.g., session establishment, modification, and publication, including tunnel maintenance between UPF and AN nodes), UE IP address allocation and management (including optional authorization) (where UE IP addresses can be received from the UPF or from an external data network), DHCPv4 (server and client) and DHCPv6 (server and client) functions, the ability to respond to Address Resolution Protocol (ARP) requests and / or IPv6 neighbor request requests with local cached information based on Ethernet PDUs (e.g., the SMF responds to ARP and / or IPv6 neighbor request requests by providing the MAC address corresponding to the IP address sent in the request), selection and control of user plane functions (including controlling the UPF to proxy ARP or IPv6 neighbor discovery or forwarding all ARP / IPv6 neighbor request traffic to the SMF for Ethernet PDU sessions), traffic-directing configuration at the UPF to route traffic to the appropriate destination, and 5G VN group management (e.g., maintaining the topology of the involved PSA UPF, in the PSA...). Establish and publish N19 tunnels between UPFs, configure traffic forwarding at the UPF to apply local handover, and / or N6-based or N19-based forwarding, terminate the interface for policy control functions, lawful interception (for SM events and interfaces to the LI system), charge for data collection and support the billing interface, control and coordinate billing data collection at the UPF, terminate the SM portion of NAS messages, downlink data notification, initiator of AN-specific SM information sent to the AN via the AMF through N2, determination of the SSC mode of the session, control plane CIoT 5GS optimization, header compression, act as an I-SMF in the deployment of insertable / removable / repositionable I-SMFs, configure external parameters (expected UE behavior parameters or network configuration parameters), P-CSCF discovery for IMS services, roaming functions (e.g., handling local implementation to apply QoS). SLA (VPLMN), charging data collection and charging interface (VPLMN) and / or lawful interception (in the VPLMN for SM events and interfaces to LI systems), interaction with external DNs to transmit signaling for PDU session authentication / authorization for external DNs and / or instructing UPF and NG-RAN to perform redundant transmissions on N3 / N9 interfaces. Some or all of the SMF functions may be supported in a single instance of the SMF. However, in some implementations, not all functions need to be supported in instances of network slices. In addition to functionality, SMF 1116 may include policy-related functions.

[0126] SCP 1118 includes one or more of the following functions: indirect communication; delegated discovery; message forwarding and routing to the destination NF / NF service; communication security (e.g., authorization for NF service consumers to access NF service manufacturer APIs), load balancing, monitoring, overload control, etc.; and / or optionally, interaction with a UDR to resolve UDM group ID / UDR group ID / AUSF group ID / PCF group ID / CHF group ID / HSS group ID based on UE identity (e.g., SUPI or IMPI / IMPU). Some or all of the SCP functions may be supported in a single instance of the SCP. In some implementations, SCP 1118 may be deployed in a distributed manner and / or more than one SCP may exist in the communication path between NF services. SCPs may be deployed at the PLMN level, shared slice level, and slice-specific level. Carrier deployments may be left to ensure that the SCP can communicate with the relevant NRF.

[0127] UE 1120 may include devices with radio communication capabilities. For example, UE 1120 may include a smartphone (e.g., a handheld touchscreen mobile computing device that can connect to one or more cellular networks). UE 1120 may also include any mobile or non-mobile computing device, such as a personal data assistant (PDA), pager, laptop computer, desktop computer, wireless phone, or any computing device that includes a wireless communication interface. UE is also referred to as a client, mobile phone, mobile device, mobile terminal, user terminal, mobile unit, mobile station, mobile user, subscriber, user, remote station, access agent, user agent, receiver, radio equipment, reconfigurable radio equipment, or reconfigurable mobile device. UE 1120 may include an IoT UE, which may include a network access layer designed to utilize low-power IoT applications with short-lived UE connections. The IoT UE may exchange data with an MTC server or device via a PLMN, other UEs using ProSe or D2D communication, sensor networks, or IoT networks using technologies such as M2M, MTC, or mMTC. M2M or MTC data exchange may be machine-initiated data exchange. An IoT network describes interconnected IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure). IoT UEs may execute background applications (e.g., keeping track of activity messages, status updates, etc.) to facilitate connectivity within the IoT network.

[0128] UE 1120 can be configured to connect or communicatively couple with (R)AN 1122 via radio interface 1130. This radio interface can be a physical communication interface or layer configured to operate using cellular communication protocols such as GSM, CDMA network protocols, keyless to reach (PTT), cellular PTT (POC), UMTS, 3GPP LTE, 5G, NR, etc. For example, UE 1120 and (R)AN 1122 can use a Uu interface (e.g., an LTE-Uu interface) to exchange control plane data via a protocol stack including PHY, MAC, RLC, PDCP, and RRC layers. DL transmissions can be made from (R)AN 1122 to UE 1120, and UL transmissions can be made from UE 1120 to (R)AN 1122. UE 1120 can also use a sidelink to communicate directly with another UE (not shown) for D2D, P2P, and / or ProSe communication. For example, the ProSe interface may include one or more logical channels, including but not limited to the Physical Side Link Control Channel (PSCCH), Physical Side Link Shared Channel (PSSCH), Physical Side Link Discovery Channel (PSDCH), and Physical Side Link Broadcast Channel (PSBCH).

[0129] (R)AN 1122 may include one or more access nodes, which may be referred to as a base station (BS), node B, evolved Node B (eNB), next-generation Node B (gNB), RAN node, controller, transport receiving point (TRP), etc., and may include ground stations (e.g., terrestrial access points) or satellite stations that provide coverage within a geographic area (e.g., a cellular base station). (R)AN 1122 may include one or more RAN nodes for providing macrocells, picocells, femtocells, or other types of cells. Macrocells may cover a relatively large geographic area (e.g., with a radius of several kilometers) and may allow UEs to have unrestricted access with a service subscription. Picocells may cover a relatively small geographic area and may allow UEs to have unrestricted access with a service subscription. Femtocells may cover a relatively small geographic area (e.g., a home) and may allow restricted access for UEs associated with a femtocell (e.g., a UE in a closed subscriber group (CSG), a UE of a user in a home, etc.).

[0130] Although not shown, multiple RAN nodes (such as (R)AN 1122) may be used, with Xn interfaces defined between two or more nodes. In some specific implementations, the Xn interface may include an Xn user plane (Xn-U) interface and an Xn control plane (Xn-C) interface. Xn-U provides non-guaranteed delivery of user plane PDUs and supports / provides data forwarding and flow control functions. Xn-C provides management and error handling functions for managing the functionality of the Xn-C interface; mobility support for UE 1120 in connected modes (e.g., CM-CONNECTED) includes functions for managing UE mobility in connected modes between one or more (R)AN nodes. This mobility support may include context transfer from the old (source) serving (R)AN node to the new (target) serving (R)AN node; and control of user plane tunnels between the old (source) serving (R)AN node and the new (target) serving (R)AN node.

[0131] The UPF 1124 can serve as an anchor point for mobility within and between RATs, an external PDU session point interconnected with the DN 1126, and a branch point supporting multi-donor PDU sessions. The UPF 1124 can also perform packet routing and forwarding, packet inspection, user plane portion enforcement of policy rules, lawful packet interception (UP collection), traffic usage reporting, QoS processing on the user plane (e.g., packet filtering, gating, UL / DL rate enforcement), uplink traffic authentication (e.g., SDF-to-QoS flow mapping), transport-level packet marking in uplink and downlink, and downlink packet buffering and downlink data notification triggering. The UPF 1124 may include an uplink classifier to support routing traffic flows to the data network. The DN 1126 may represent various network operator services, Internet access, or third-party services. The DN 1126 may include, for example, an application server.

[0132] Figure 12 This is a block diagram of a configurable exemplary UE 1200 according to various embodiments of the present disclosure, including instructions executed on a computer-readable medium corresponding to any of the exemplary methods and / or processes described herein. UE 1200 includes one or more processors 1202, transceiver 1204, memory 1206, user interface 1208, and control interface 1210.

[0133] One or more processors 1202 may include, for example, an application processor, an audio digital signal processor, a central processing unit, and / or one or more baseband processors. Each of the one or more processors 1202 may include internal memory and / or may include an interface for communicating with external memory (including memory 1206). The internal or external memory may store software code, programs, and / or instructions executable by one or more processors 1202 to configure and / or facilitate the UE 1200 to perform various operations, including those described herein. For example, the execution of instructions may configure the UE 1200 to communicate using one or more wired or wireless communication protocols (including one or more wireless communication protocols standardized by 3GPP, such as those commonly referred to as 5G / NR, LTE, LTE-A, UMTS, HSPA, GSM, GPRS, EDGE, etc.) or any other current or future protocols that can be used in conjunction with one or more transceivers 1204, user interface 1208, and / or control interface 1210. For example, one or more processors 1202 may execute program code stored in memory 1206 or other memory corresponding to the MAC, RLC, PDCP, and RRC layer protocols standardized by 3GPP (e.g., for NR and / or LTE). Alternatively, processor 1202 may execute program code stored in memory 1206 or other memory that, together with one or more transceivers 1204, implements corresponding PHY layer protocols, such as Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), and Single Carrier Frequency Division Multiple Access (SC-FDMA).

[0134] Memory 1206 may include memory regions for one or more processors 1202 to store variables used in the protocols, configurations, controls, and other functions of UE 1200 (including operations corresponding to or including any of the exemplary methods and / or processes described herein). Furthermore, memory 1206 may include non-volatile memory (e.g., flash memory), volatile memory (e.g., static or dynamic RAM), or combinations thereof. Additionally, memory 1206 may interact with memory time slots through which one or more removable memory cards of various formats (e.g., SD cards, Memory Sticks, Compact Flash, etc.) can be inserted and removed.

[0135] One or more transceivers 1204 may include radio frequency transmitter and / or receiver circuitry that facilitates communication between the UE 1200 and other equipment supporting similar wireless communication standards and / or protocols. For example, one or more transceivers 1204 may include switches, mixer circuitry, amplifier circuitry, filter circuitry, and synthesizer circuitry. Such RF circuitry systems may include a receive signal path having circuitry for down-converting RF signals received from a front-end module (FEM) and providing baseband signals to one or more processors 1202. The RF circuitry may also include a transmit signal path that may include circuitry for up-converting the baseband signals provided by the baseband processor and providing an RF output signal for transmission to the FEM. The FEM may include a receive signal path that may include circuitry configured to operate on RF signals received from one or more antennas, amplify the received signals, and provide an amplified version of the received signals to the RF circuitry for further processing. The FEM may also include a transmit signal path that may include circuitry configured to amplify transmit signals provided by the RF circuitry for transmission by one or more antennas. In various implementations, amplification along the transmit or receive signal path can be performed only in the RF circuitry, only in the FEM, or in both the RF and FEM circuitries. In some implementations, the FEM circuitry may include a TX / RX switch to switch between transmit and receive mode operation.

[0136] In some exemplary embodiments, one or more transceivers 1204 include transmitters and receivers that enable device 1200 to communicate with various 5G / NR networks according to various protocols and / or methods proposed for standardization by 3GPP and / or other standards bodies. For example, such functionality may operate cooperatively with one or more processors 1202 to implement a PHY layer based on OFDM, OFDMA, and / or SC-FDMA technologies, as described herein with reference to other figures.

[0137] User interface 1208 may take various forms depending on the specific implementation, or may not be present in UE 1200. In some implementations, user interface 1208 includes a microphone, speaker, slide button, pressable button, display, touchscreen display, mechanical or virtual keypad, mechanical or virtual keyboard, and / or any other user interface features typically present on a mobile phone. In other implementations, UE 1200 may include a tablet computing device with a large touchscreen display. In such implementations, one or more of the mechanical features of user interface 1208 may be replaced by equivalent or functionally equivalent virtual user interface features (e.g., virtual keypad, virtual buttons, etc.) implemented using a touchscreen display, as is well known to those skilled in the art. In other implementations, UE 1200 may be a digital computing device, such as a laptop computer, desktop computer, workstation, etc., which includes a mechanical keyboard that can be integrated, detached, or removable according to a particular exemplary implementation. Such digital computing devices may also include a touchscreen display. Many example implementations of the UE 1200 with a touchscreen display are capable of receiving user input, such as input related to exemplary methods and / or processes described herein or known to those skilled in the art.

[0138] In some exemplary embodiments of this disclosure, UE 1200 includes an orientation sensor that can be used in various ways by features and functions of UE 1200. For example, UE 1200 can use the output of the orientation sensor to determine when a user has changed the physical orientation of the touchscreen display of UE 1200. An indication signal from the orientation sensor can be used by any application executing on UE 1200 to automatically change the orientation of the screen display (e.g., from portrait to landscape) when the indication signal indicates a change of approximately 90 degrees in the physical orientation of the device. Thus, the application is able to maintain the screen display in a user-readable manner regardless of the physical orientation of the device. Additionally, the output of the orientation sensor can be used in conjunction with various exemplary embodiments of this disclosure.

[0139] The control interface 1210 may take various forms depending on the specific implementation. For example, the control interface 1210 may include an RS-232 interface, an RS-485 interface, a USB interface, an HDMI interface, a Bluetooth interface, an IEEE (“FireWire”) interface, and an I / O interface. 2 Interfaces include C-type interfaces, PCMCIA interfaces, etc. In some exemplary embodiments of this disclosure, control interface 1260 may include an IEEE 802.3 Ethernet interface, as described above. In some embodiments of this disclosure, control interface 1210 may include analog interface circuitry, including, for example, one or more digital-to-analog (D / A) converters and / or analog-to-digital (A / D) converters.

[0140] Those skilled in the art will recognize that the list of features, interfaces, and radio frequency communication standards above is merely exemplary and not limited to the scope of this disclosure. In other words, UE 1200 may include more than Figure 12 Further functionalities are shown, including, for example, a video and / or still image camera, a microphone, a media player, and / or a recorder. Additionally, one or more transceivers 1204 may include circuitry for communicating using additional radio frequency communication standards, including Bluetooth, GPS, and / or others. Furthermore, one or more processors 1202 may execute software code stored in memory 1206 to control such additional functionalities. For example, directional velocity and / or position estimates output from a GPS receiver can be used by any application executing on the UE 1200, including various exemplary methods and / or computer-readable media according to various exemplary embodiments of this disclosure.

[0141] Figure 13 This is a block diagram of a configurable exemplary network node 1300 according to various embodiments of the present disclosure, including instructions executed on a computer-readable medium corresponding to any of the example methods and / or processes described herein.

[0142] Network node 1300 includes one or more processors 1302, a radio network interface 1304, a memory 1306, a core network interface 1308, and other interfaces 1310. Network node 1300 may include, for example, a base station, an eNB, a gNB, an access node, or components thereof.

[0143] One or more processors 1302 may include any type of processor or processing circuitry and may be configured to perform one of the methods or processes disclosed herein. Memory 1306 may store software code, programs, and / or instructions executable by one or more processors 1302 to configure network node 1300 to perform various operations, including those described herein. For example, execution of such stored instructions may configure network node 1300 to communicate with one or more other devices using protocols (including one or more methods and / or processes described above) according to various embodiments of this disclosure. Furthermore, execution of such stored instructions may configure and / or facilitate network node 1300 to communicate with one or more other devices using other protocols or protocol layers (such as one or more of the PHY, MAC, RLC, PDCP, and RRC layer protocols standardized by 3GPP for LTE, LTE-A, and / or NR, or any other higher-level protocol used in conjunction with radio network interface 1304 and core network interface 1308). By way of example, and not limitation, the core network interface 1308 includes an S1 interface, and the radio network interface 1304 may include a Uu interface, such as those standardized by 3GPP. The memory 1306 may also store variables used in the protocols, configurations, control, and other functions of the network node 1300. Therefore, the memory 1306 may include non-volatile memory (e.g., flash memory, hard disk, etc.), volatile memory (e.g., static or dynamic RAM), network-based (e.g., “cloud”) storage devices, or combinations thereof.

[0144] The radio network interface 1304 may include a transmitter, receiver, signal processor, ASIC, antenna, beamforming unit, and other circuitry enabling the network node 1300 to communicate with other equipment (in some embodiments, such as multiple compatible user equipment (UEs)). In some embodiments, the network node 1300 may include various protocols or protocol layers, such as the PHY, MAC, RLC, PDCP, and RRC layer protocols standardized by 3GPP for LTE, LTE-A, and / or 5G / NR. According to further embodiments of this disclosure, the radio network interface 1304 may include a PHY layer based on OFDM, OFDMA, and / or SC-FDMA technologies. In some embodiments, the functionality of such a PHY layer may be provided collaboratively by the radio network interface 1304 and one or more processors 1302.

[0145] The core network interface 1308 may include a transmitter, a receiver, and other circuitry enabling the network node 1300 to communicate with other equipment in the core network (in some embodiments, such as a circuit-switched (CS) and / or packet-switched (PS) core network). In some embodiments, the core network interface 1308 may include an S1 interface standardized by 3GPP. In some embodiments, the core network interface 1308 may include one or more interfaces to one or more SGW, MME, SGSN, GGSN, and other physical devices, including functions known to those skilled in the art in GERAN, UTRAN, E-UTRAN, and CDMA2000 core networks. In some embodiments, these one or more interfaces may be multiplexed together on a single physical interface. In some embodiments, the lower layers of the core network interface 1308 may include one or more of Asynchronous Transfer Mode (ATM), Internet Protocol over Ethernet (IP), SDH over fiber, T1 / E1 / PDH over copper, microwave radio, or other wired or wireless transmission technologies known to those skilled in the art.

[0146] Other interfaces 1310 may include transmitters, receivers, and other circuitry that enables network node 1300 to communicate with external networks, computers, databases, etc., for the operation, management, and maintenance of network node 1300 or other network equipment operatively connected thereto.

[0147] Figure 14 This is a block diagram illustrating a component 1400, according to some exemplary embodiments, capable of reading instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and capable of executing any or more of the methods discussed herein. Specifically, Figure 14 A schematic representation of hardware resources 1402 is shown, including one or more processors 1412 (or processor cores), one or more memory / storage devices 1418, and one or more communication resources 1420, each of which is communicatively coupled via bus 1422. For implementations utilizing node virtualization (e.g., NFV), an executable hypervisor 1404 provides an execution environment for enabling one or more network slices / subslices to utilize hardware resources 1402.

[0148] Processor 1412 (e.g., a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a complex instruction set computing (CISC) processor, a graphics processing unit (GPU), a digital signal processor (DSP) (such as a baseband processor), an application-specific integrated circuit (ASIC), a radio frequency integrated circuit (RFIC), another processor, or any suitable combination thereof) may include, for example, processor 1414 and processor 1416.

[0149] The memory / storage device 1418 may include main memory, disk storage, or any suitable combination thereof. The memory / storage device 1418 may include, but is not limited to, any type of volatile or non-volatile memory, such as dynamic random access memory (DRAM), static random access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state storage devices, etc.

[0150] Communication resource 1420 may include interconnect or network interface components or other suitable devices for communicating with one or more peripheral devices 1406 or one or more databases 1408 via network 1410. For example, communication resource 1420 may include wired communication components (e.g., for coupling via Universal Serial Bus (USB), cellular communication components, NFC components, etc. Components (e.g.) (low power consumption) Components and other communication components.

[0151] Instructions 1424 may include software, programs, applications, applets, or other executable code for causing at least one processor in processor 1412 to perform any or more of the methods discussed herein. Instructions 1424 may reside wholly or partially within processor 1412 (e.g., within the processor's cache), memory / storage device 1418, or any suitable combination thereof. Furthermore, any portion of instructions 1424 may be transferred to hardware resource 1402 from any combination of peripheral device 1406 or database 1408. Therefore, the memory of processor 1412, memory / storage device 1418, peripheral device 1406, and database 1408 are examples of computer-readable and machine-readable media.

[0152] For one or more embodiments, at least one of the components shown in one or more of the foregoing figures may be configured to perform one or more operations, techniques, processes, and / or methods described in the Embodiments section below. For example, the baseband circuitry described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples below. As another example, circuitry associated with the UE, base station, network element, etc., described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples shown in the Examples section below.

[0153] Embodiment section

[0154] The following examples relate to other implementation schemes.

[0155] Example 1 is an apparatus for a user equipment (UE) to perform Sound Reference Signal (SRS) handover. The apparatus includes a transceiver and a processor (e.g., a baseband processor). The processor is configured to transmit one or more SRS signals to a base station via the transceiver using multiple SRS resources in a set of SRS resources configured for SRS handover, based on a first combination of downlink (DL) and uplink (UL) antenna ports. For UE power saving purposes, the processor is also configured to disable one or more of the DL and UL antenna ports. The processor is further configured to reconfigure multiple SRS resources in the set of SRS resources for SRS handover based on a second combination of the DL and UL antenna ports.

[0156] Example 2 includes the apparatus according to Example 1, wherein disabling one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes using a subset of the multiple SRS resources to transmit one or more SRSs based on a second combination of the DL antenna ports and UL antenna ports.

[0157] Example 3 includes the apparatus according to Example 1, wherein disabling one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring the plurality of SRS resources includes remapping a subset of the plurality of SRS resources to one or more active DL ports in a second combination of the DL antenna ports and UL antenna ports to provide repetitive gain for one or more SRSs.

[0158] Example 4 includes the apparatus according to Example 3, wherein the processor is further configured to discard all multiple SRS resources in the SRS resource set in response to determining that a duplicate SRS resource on one or more active DL ports conflicts with another UL signal.

[0159] Example 5 includes the apparatus according to Example 3, wherein the processor is further configured to discard only the duplicate SRS resources in the SRS resource set in response to determining that a duplicate SRS resource on one or more active DL ports conflicts with another UL signal.

[0160] Example 6 includes the apparatus according to Example 1, wherein disabling one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes waiting to use the multiple SRS resources to transmit one or more SRSs until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of the DL antenna ports and UL antenna ports.

[0161] Example 7 includes the apparatus according to Example 1, wherein disabling one or more of the DL antenna port and UL antenna port includes at least one UL antenna port in a first combination of disabling the DL antenna port and UL antenna port, and wherein reconfiguring multiple SRS resources includes waiting to use multiple SRS resources to transmit one or more SRS until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of the DL antenna port and UL antenna port.

[0162] Example 8 includes the apparatus according to Example 1, wherein shutting down one or more of the DL antenna ports and UL antenna ports includes at least one UL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes repeatedly transmitting a set of SRS resources at different transmission times according to the first combination of the DL antenna ports and UL antenna ports until the number of SRS resources transmitted is greater than the ratio of active DL antenna ports to active UL antenna ports.

[0163] Example 9 includes the apparatus according to Example 1, wherein disabling one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port and at least one UL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes waiting to use the multiple SRS resources to transmit one or more SRSs, regardless of whether the multiple SRS resources are triggered, until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of the DL antenna ports and UL antenna ports.

[0164] Embodiment 10 includes the apparatus according to Embodiment 1, wherein shutting down one or more of the DL antenna ports and the UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in a first combination of the DL antenna ports and the UL antenna ports so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), wherein corresponding to the first combination of the DL antenna ports and the UL antenna ports, x represents a first number of transmit (T) chains and y represents a first number of receive (R) chains, wherein corresponding to the second combination of the DL antenna ports and the UL antenna ports, x' represents a second number of T chains and y' represents a second number of R chains, and wherein: if ceil(y' / x') is greater than ceil(y / x), such that more SRS resources will be used, the UE repeatedly transmits a set of SRS resources configured with xTyR until the number of SRS resources is greater than ceil(y' / x'); if ceil(y' / x') is less than ceil(y / x), such that some SRS resources are redundant, the UE does not transmit the SRS resources corresponding to the y - y' ports for the SRS resource set antenna switch xTyR, or the UE transmits all the SRS resources for the SRS resource set antenna switch xTyR and the SRS resources corresponding to the y - y' receive chains are remapped to other active DL ports to achieve repetition gain; or if ceil(y' / x') is the same as ceil(y / x), the UE changes the port mapping and the transmitted ports for each SRS resource and transmits the entire SRS resource set.

[0165] Embodiment 11 includes the apparatus according to Embodiment 1, wherein shutting down one or more of the DL antenna ports and the UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in a first combination of the DL antenna ports and the UL antenna ports so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), wherein corresponding to the first combination of the DL antenna ports and the UL antenna ports, x represents a first number of transmit (T) chains and y represents a first number of receive (R) chains, wherein corresponding to the second combination of the DL antenna ports and the UL antenna ports, x' represents a second number of T chains and y' represents a second number of R chains, wherein ceil(y' / x') = C, wherein the UE uses antenna switching on SRS resource c for c ∈ 0,..., C - 2 and uses x' transmit chains, and the x' transmit chains are mapped to downlink ports c·X', c·X' + 1,..., c·X' + X' - 1, and wherein the UE uses antenna switching on SRS resource c - 1 and uses (y' - (C - 1)x') transmit chains, and these transmit chains are mapped to downlink ports c·X', c·X' + 1,..., y' - 1, c = C - 2.

[0166] Example 12 is a method for a user equipment (UE) to perform a Sound Reference Signal (SRS) handover. The method includes transmitting one or more SRSs using multiple SRS resources in a set of SRS resources configured for SRS handover, based on a first combination of downlink (DL) antenna ports and uplink (UL) antenna ports. The method also includes disabling one or more of the DL and UL antenna ports for UE power saving purposes. The method further includes reconfiguring multiple SRS resources in the set of SRS resources for SRS handover based on a second combination of the DL and UL antenna ports.

[0167] Example 13 includes the method according to Example 12, wherein disabling one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring the plurality of SRS resources includes using a subset of the plurality of SRS resources to transmit one or more SRS based on a second combination of the DL antenna ports and UL antenna ports.

[0168] Example 14 includes the method according to Example 12, wherein shutting down one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring the plurality of SRS resources includes remapping a subset of the plurality of SRS resources to one or more active DL ports in a second combination of the DL antenna ports and UL antenna ports to provide repetitive gain for one or more SRSs.

[0169] Example 15 includes the method according to Example 14, further comprising, in response to determining that a duplicate SRS resource on one or more active DL ports conflicts with another UL signal, discarding all multiple SRS resources in the SRS resource set.

[0170] Example 16 includes the method according to Example 14, further comprising, in response to determining that a duplicate SRS resource on one or more active DL ports conflicts with another UL signal, discarding only the duplicate SRS resource in the SRS resource set.

[0171] Example 17 includes the method according to Example 12, wherein shutting down one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes waiting to use multiple SRS resources to transmit one or more SRSs until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of the DL antenna ports and UL antenna ports.

[0172] Example 18 includes the method according to Example 12, wherein shutting down one or more of the DL antenna ports and UL antenna ports includes at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes waiting to use multiple SRS resources to transmit one or more SRSs until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of DL antenna ports and UL antenna ports.

[0173] Example 19 includes the method according to Example 12, wherein shutting down one or more of the DL antenna ports and UL antenna ports includes at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes repeatedly transmitting a set of SRS resources at different transmission times according to the first combination of DL antenna ports and UL antenna ports until the number of SRS resources transmitted is greater than the ratio of active DL antenna ports to active UL antenna ports.

[0174] Example 20 includes the method according to Example 12, wherein disabling one or more of the DL antenna ports and UL antenna ports includes at least one DL antenna port and at least one UL antenna port in a first combination of disabling the DL antenna ports and UL antenna ports, and wherein reconfiguring multiple SRS resources includes waiting to use the multiple SRS resources to transmit one or more SRSs, regardless of whether the multiple SRSs are triggered, until an SRS configuration is received from the network device to configure the SRS resource set based on a second combination of the DL antenna ports and UL antenna ports.

[0175] Embodiment 21 includes the method according to Embodiment 12, wherein closing one or more of the DL antenna ports and UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), where corresponding to the first combination of DL antenna ports and UL antenna ports, x represents the first number of transmit (T) chains and y represents the first number of receive (R) chains, where corresponding to the second combination of DL antenna ports and UL antenna ports, x' represents the second number of T chains and y' represents the second number of R chains, and wherein: if ceil(y' / x') is greater than ceil(y / x), such that more SRS resources will be used, the UE repeatedly transmits the SRS resource set configured with xTyR until the number of SRS resources is greater than ceil(y' / x'); if ceil(y' / x') is less than ceil(y / x), such that some SRS resources are redundant, the UE does not transmit the SRS resources corresponding to the y - y' ports for the SRS resource set antenna switch xTyR, or the UE transmits all the SRS resources for the SRS resource set antenna switch xTyR and the SRS resources corresponding to the y - y' receive chains are remapped to other active DL ports to achieve repetition gain; or if ceil(y' / x') is the same as ceil(y / x), the UE changes the port mapping and the transmitted ports for each SRS resource and transmits the entire SRS resource set.

[0176] Embodiment 22 includes the method according to Embodiment 12, wherein closing one or more of the DL antenna ports and UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in a first combination of DL antenna ports and UL antenna ports so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), where corresponding to the first combination of DL antenna ports and UL antenna ports, x represents the first number of transmit (T) chains and y represents the first number of receive (R) chains, where corresponding to the second combination of DL antenna ports and UL antenna ports, x' represents the second number of T chains and y' represents the second number of R chains, where ceil(y' / x') = C, wherein the UE uses antenna switching on SRS resource c for c ∈ 0,..., C - 2 and uses x' transmit chains, and the x' transmit chains are mapped to downlink ports c·X', c·X'+1,..., c·X'+X'-1, and wherein the UE uses antenna switching on SRS resource c - 1 and uses (y' - (C - 1)x') transmit chains, and these transmit chains are mapped to downlink ports c·X', c·X'+1,..., y' - 1, c = C - 2.

[0177] Example 23 is a method for a base station in a wireless network. The method includes receiving, at the base station, a power-saving message from a user equipment (UE) indicating a preference for reducing the number of multiple-input multiple-output (MIMO) layers. The method also includes generating Sounding Reference Signal (SRS) configuration information in response to the power-saving message to configure an SRS resource set for SRS antenna handover based on a combination of active downlink (DL) antenna ports and active uplink (UL) antenna ports at the UE. The method further includes sending the SRS configuration information to the UE.

[0178] Example 24 includes the method according to Example 23, and further includes: determining that the number of active DL antenna ports is not an integer multiple of the number of active UL antenna ports; and configuring different SRS resources with different antenna ports in an SRS resource set configured with SRS antenna switching.

[0179] Example 25 includes the method according to Example 23, further comprising: determining that the number of active DL antenna ports is not an integer multiple of the number of active UL antenna ports; and configuring the same number of antenna ports for all SRS resources in the SRS resource set configured with SRS antenna switching.

[0180] Example 26 includes the method according to Example 25, further comprising mapping the last SRS resource in the SRS resource set to a previously used port to achieve repetition gain.

[0181] Example 27 may include an apparatus comprising one or more elements for performing any of the methods described or associated with any of the above embodiments or any other methods or processes described herein.

[0182] Example 28 may include one or more non-transitory computer-readable media, the one or more non-transitory computer-readable media including instructions that, when executed by one or more processors of an electronic device, cause the electronic device to perform one or more elements of the method or any other method or process described herein as described or associated with any of the above embodiments.

[0183] Example 29 may include an apparatus comprising logic components, modules, or circuitry for performing one or more elements of the methods described or associated with any of the above embodiments or any other methods or processes described herein.

[0184] Example 30 may include any of the methods, techniques, or processes described or related to any of the above examples, or a portion or component thereof.

[0185] Example 31 may include an apparatus comprising: one or more processors and one or more computer-readable media, the one or more computer-readable media including instructions that, when executed by the one or more processors, cause the one or more processors to perform any of the methods, techniques or processes or portions thereof described or associated with any of the above embodiments.

[0186] Example 32 may include any of the signals or parts or components described or associated with any of the above examples.

[0187] Example 33 may include any datagram, packet, frame, segment, protocol data unit (PDU) or message or part or component thereof described or associated with any of the above examples, or otherwise described in this disclosure.

[0188] Example 34 may include a data-encoded signal or part or component thereof described or associated with any of the above examples, or otherwise described in this disclosure.

[0189] Example 35 may include a signal or part or component thereof encoded as a datagram, packet, frame, segment, PDU or message as described or associated with any of the above examples, or otherwise described in this disclosure.

[0190] Example 36 may include an electromagnetic signal carrying computer-readable instructions, wherein execution of the computer-readable instructions by one or more processors will cause the one or more processors to perform any of the methods, techniques or processes or portions thereof described or associated with any of the above embodiments.

[0191] Example 37 may include a computer program comprising instructions, wherein execution of the program by a processing element causes the processing element to perform any of the methods, techniques, or processes or portions thereof described or associated with any of the above embodiments.

[0192] Example 38 may include signals in a wireless network as shown and described herein.

[0193] Example 39 may include methods for communicating in a wireless network as shown and described herein.

[0194] Example 40 may include a system for providing wireless communication as shown and described herein.

[0195] Example 41 may include a device for providing wireless communication as shown and described herein.

[0196] Unless otherwise expressly stated, any of the above embodiments may be combined with any other embodiment (or combination of embodiments). The foregoing description of one or more specific embodiments provides illustration and description, but is not intended to be exhaustive or to limit the scope of the embodiments to the precise forms disclosed. In view of the teachings above, modifications and variations are possible, or modifications and variations may be obtained from the practice of various embodiments.

[0197] Implementations and specific embodiments of the systems and methods described herein may include various operations embodied in machine-executable instructions to be executed by a computer system. The computer system may include one or more general-purpose or special-purpose computers (or other electronic devices). The computer system may include hardware components, including specific logical components for performing the operations, or may include a combination of hardware, software, and / or firmware.

[0198] It should be recognized that the systems described herein include descriptions of specific implementations. These implementations may be combined into a single system, partially integrated into other systems, divided into multiple systems, or otherwise partitioned or combined. Furthermore, it is conceivable to use parameters, attributes, aspects, etc., of one implementation in another implementation. For clarity, these parameters, attributes, aspects, etc., are described only in one or more implementations, and it should be recognized that unless specifically stated herein, these parameters, attributes, aspects, etc., may be combined with or substituted for parameters, attributes, aspects, etc., of another implementation.

[0199] As is widely recognized, the use of personally identifiable information should comply with privacy policies and practices that are generally accepted to meet or exceed industry or governmental requirements for protecting user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly explained to users.

[0200] Although the foregoing has been described in considerable detail for clarity, it will be apparent that certain changes and modifications can be made without departing from the principles of the invention. It should be noted that many alternative ways exist to implement both the processes and apparatus described herein. Therefore, embodiments of the invention should be considered illustrative rather than restrictive, and this specification is not limited to the details given herein, but can be modified within the scope of the appended claims and their equivalents.

Claims

1. An apparatus for a user equipment (UE) to perform a Sound Reference Signal (SRS) handover, the apparatus comprising: transceiver; as well as Processor, the processor being configured to: Using a first combination of downlink DL antenna ports and uplink UL antenna ports, multiple SRS resources in an SRS resource set configured for SRS handover are used to transmit one or more SRS to the base station via the transceiver. For UE power saving purposes, one or more of the DL antenna ports and the UL antenna ports are turned off, wherein turning off one or more of the DL antenna ports and the UL antenna ports includes disabling at least one DL antenna port in the first combination of the DL antenna port and the UL antenna port; and In response to deactivating at least one DL antenna port in the first combination of the DL antenna port and the UL antenna port, the plurality of SRS resources in the SRS resource set for SRS handover are reconfigured according to a second combination of the DL antenna port and the UL antenna port, wherein reconfiguring the plurality of SRS resources includes using a subset of the plurality of SRS resources to transmit the one or more SRSs based on the second combination of the DL antenna port and the UL antenna port.

2. The apparatus of claim 1, wherein reconfiguring the plurality of SRS resources includes remapping a subset of the plurality of SRS resources to one or more active DL ports in the second combination of DL antenna ports and UL antenna ports to provide repetitive gain for the one or more SRSs.

3. The apparatus of claim 2, wherein the processor is further configured to discard all of the plurality of SRS resources in the SRS resource set in response to determining that a duplicate SRS resource on one or more active DL ports conflicts with another UL signal.

4. The apparatus of claim 2, wherein the processor is further configured to discard only the repeated SRS resources in the SRS resource set in response to determining that a repeated SRS resource on one or more active DL ports conflicts with another UL signal.

5. The apparatus of claim 1, wherein reconfiguring the plurality of SRS resources includes waiting to use the plurality of SRS resources to transmit the one or more SRS until an SRS configuration is received from the network device to configure the SRS resource set based on the second combination of the DL antenna port and the UL antenna port.

6. The apparatus of claim 1, wherein shutting down one or more of the DL antenna ports and the UL antenna ports further includes disabling at least one UL antenna port in the first combination of the DL antenna ports and the UL antenna ports, and wherein reconfiguring the plurality of SRS resources includes waiting to use the plurality of SRS resources to transmit the one or more SRSs until an SRS configuration is received from the network device to configure the SRS resource set based on the second combination of the DL antenna ports and the UL antenna ports.

7. The apparatus according to claim 1, wherein closing one or more of the DL antenna ports and the UL antenna ports further comprises deactivating at least one UL antenna port in the first combination of the DL antenna port and the UL antenna port, and wherein reconfiguring the plurality of SRS resources comprises repeating transmission of the set of SRS resources at different transmission opportunities according to the first combination of the DL antenna port and the UL antenna port until the number of the transmitted SRS resources is greater than the ratio of the active DL antenna ports to the active UL antenna ports.

8. The apparatus according to claim 1, wherein closing one or more of the DL antenna ports and the UL antenna ports further comprises deactivating at least one DL antenna port and at least one UL antenna port in the first combination of the DL antenna port and the UL antenna port, and wherein reconfiguring the plurality of SRS resources comprises waiting to transmit the one or more SRSs using the plurality of SRS resources, regardless of whether the plurality of SRS resources are triggered, until an SRS configuration is received from a network device to configure the set of SRS resources based on the second combination of the DL antenna port and the UL antenna port.

9. The apparatus according to claim 1, wherein closing one or more of the DL antenna ports and the UL antenna ports further comprises deactivating at least one DL antenna port and at least one UL antenna port in the first combination of the DL antenna port and the UL antenna port so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), where corresponding to the first combination of the DL antenna port and the UL antenna port, x represents the first number of transmit T chains and y represents the first number of receive R chains, and where corresponding to the second combination of the DL antenna port and the UL antenna port, x' represents the second number of T chains and y' represents the second number of R chains, and wherein: If ceil(y' / x') is greater than ceil(y / x), such that more SRS resources will be used, the UE repeatedly transmits the set of SRS resources configured with xTyR until the number of SRS resources is greater than ceil(y' / x'); If ceil(y' / x') is less than ceil(y / x), such that some SRS resources are redundant, the UE does not transmit the SRS resources corresponding to the y - y' ports for the SRS resource set antenna switch xTyR, or the UE transmits all the SRS resources for the SRS resource set antenna switch xTyR and the SRS resources corresponding to the y - y' receive chains are remapped to other active DL ports to achieve repetition gain; or If ceil(y' / x') is the same as ceil(y / x), the UE changes the port mapping and the transmitted ports for each SRS resource and transmits the entire set of SRS resources.

10. A method for a user equipment UE to perform sounding reference signal SRS switching, the method comprising: One or more SRSs are transmitted using multiple SRS resources in an SRS resource set configured for SRS handover, based on a first combination of downlink DL antenna ports and uplink UL antenna ports. For UE power saving purposes, one or more of the DL antenna ports and the UL antenna ports are turned off, wherein turning off one or more of the DL antenna ports and the UL antenna ports includes disabling at least one DL antenna port in the first combination of the DL antenna port and the UL antenna port; and In response to deactivating at least one DL antenna port in the first combination of the DL antenna port and the UL antenna port, the plurality of SRS resources in the SRS resource set for SRS handover are reconfigured according to a second combination of the DL antenna port and the UL antenna port, wherein reconfiguring the plurality of SRS resources includes using a subset of the plurality of SRS resources to transmit the one or more SRSs based on the second combination of the DL antenna port and the UL antenna port.

11. The method of claim 10, wherein reconfiguring the plurality of SRS resources includes remapping a subset of the plurality of SRS resources to one or more active DL ports in the second combination of DL antenna ports and UL antenna ports to provide repetitive gain for the one or more SRSs.

12. The method of claim 11, further comprising, in response to determining that a duplicate SRS resource on one or more active DL ports conflicts with another UL signal, discarding all of the plurality of SRS resources in the SRS resource set.

13. The method of claim 11, further comprising, in response to determining that a duplicate SRS resource on one or more active DL ports conflicts with another UL signal, discarding only the duplicate SRS resource in the SRS resource set.

14. The method of claim 10, wherein reconfiguring the plurality of SRS resources further comprises waiting to use the plurality of SRS resources to transmit the one or more SRS until an SRS configuration is received from the network device to configure the SRS resource set based on the second combination of the DL antenna port and the UL antenna port.

15. The method of claim 10, wherein disabling one or more of the DL antenna ports and UL antenna ports further includes disabling at least one UL antenna port in the first combination of the DL antenna ports and UL antenna ports, and wherein reconfiguring the plurality of SRS resources includes waiting to use the plurality of SRS resources to transmit the one or more SRSs until an SRS configuration is received from the network device to configure the SRS resource set based on the second combination of the DL antenna ports and the UL antenna ports.

16. The method according to claim 10, wherein closing one or more of the DL antenna ports and the UL antenna ports includes deactivating at least one UL antenna port in the first combination of the DL antenna port and the UL antenna port, and wherein reconfiguring the plurality of SRS resources includes repeating the transmission of the SRS resource set at different transmission opportunities according to the first combination of the DL antenna port and the UL antenna port until the number of transmitted SRS resources is greater than the ratio of the active DL antenna ports to the active UL antenna ports.

17. The method according to claim 10, wherein closing one or more of the DL antenna ports and the UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in the first combination of the DL antenna port and the UL antenna port, and wherein reconfiguring the plurality of SRS resources includes waiting to use the plurality of SRS resources to transmit the one or more SRSs, regardless of whether the plurality of SRS resources are triggered, until an SRS configuration is received from a network device to configure the SRS resource set based on the second combination of the DL antenna port and the UL antenna port.

18. The method according to claim 10, wherein closing one or more of the DL antenna ports and the UL antenna ports includes deactivating at least one DL antenna port and at least one UL antenna port in the first combination of the DL antenna port and the UL antenna port so as to change from an xTyR antenna switch to an x'Ty'R antenna switch (x' < x, y' < y), where corresponding to the first combination of the DL antenna port and the UL antenna port, x represents the first number of transmit T chains and y represents the first number of receive R chains, and where corresponding to the second combination of the DL antenna port and the UL antenna port, x' represents the second number of T chains and y' represents the second number of R chains, and wherein: if ceil(y' / x') is greater than ceil(y / x), such that more SRS resources will be used, the UE repeatedly transmits the SRS resource set configured with xTyR until the number of SRS resources is greater than ceil(y' / x'); if ceil(y' / x') is less than ceil(y / x), such that some SRS resources are redundant, the UE does not transmit the SRS resources corresponding to the y - y' ports for the SRS resource set antenna switch xTyR, or the UE transmits all the SRS resources for the SRS resource set antenna switch xTyR and the SRS resources corresponding to the y - y' receive chains are remapped to other active DL ports to achieve repetition gain; or if ceil(y' / x') is the same as ceil(y / x), the UE changes the port mapping and the transmitted ports for each SRS resource and transmits the entire SRS resource set.

Images