Method for supporting flexible configuration of eight-port sounding reference signal, and related system and apparatus

Abstract

Systems, apparatuses, and methods are described herein for supporting sounding reference signals (SRS) on eight ports using a four-size comb or a two-size comb. A network node may transmit an SRS-resource information element that includes configuration details for an SRS for eight ports using a comb size that supports the SRS for eight ports with a first number of comb offsets and a second number of comb offsets. The UE may determine whether to use a first number of comb offsets or a second number of comb offsets for SRS transmissions from eight ports for SRS-resources.

Description

TECHNICAL FIELD

[0001] The present application relates generally to wireless communication systems, including enhancements for supporting sounding reference signals on eight ports. BACKGROUND

[0002] Wireless mobile communication technology uses various standards and protocols to transmit data between base stations and wireless communication devices. For example, wireless communication system standards and protocols can include, for example, 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) (e.g., 4G), 3GPP New Radio (NR) (e.g., 5G), and Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (commonly referred to as Wi-Fi ® ).

[0003] As contemplated by 3GPP, different wireless communication system standards and protocols can use various radio access networks (RANs) for communication between base stations (which can also be commonly referred to as RAN nodes, network nodes, or simply nodes) of the RAN and wireless communication devices referred to as user equipment (UE). A 3GPP RAN can include, for example, a Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE) RAN (GERAN), Universal Terrestrial Radio Access Network (UTRAN), Evolved Universal Terrestrial Radio Access Network (E-UTRAN), and / or Next Generation Radio Access Network (NG-RAN).

[0004] Each RAN can use one or more radio access technologies (RATs) to perform communication between base stations and UEs. 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 (sometimes referred to simply as LTE), and an NG-RAN implements NR RAT (which is sometimes referred to herein as a 5G RAT, 5G NR RAT, or simply NR). In certain deployments, an E-UTRAN can also implement NR RAT. In certain deployments, an NG-RAN can also implement LTE RAT.

[0005] A base station used by a RAN can correspond to that RAN. One example of an E-UTRAN base station is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (also commonly denoted as an Evolved Node B, Enhanced Node B, eNode B, or eNB). One example of an NG-RAN base station is a Next Generation Node B (sometimes also referred to as a gNode B or gNB).

[0006] The RAN, through its connection to the core network (CN), also provides connectivity to external entities. For example, E-UTRAN can utilize an Evolved Packet Core (EPC), while NG-RAN can utilize a 5G Core Network (5GC). BRIEF DESCRIPTION OF DRAWINGS

[0007] To easily identify discussions of any particular element or act, one or more of the highest three digits in a figure number are often omitted. Thus, discussion of a spinning element or act 10 often can be identified simply by referring to the element or act number 10.

[0008] Figure 1 An SRS sequence mapping for transmission is illustrated in accordance with some embodiments.

[0009] Figure 2 A table indicating the maximum number of cyclic shifts as a function of comb structure is illustrated in accordance with some embodiments.

[0010] Figure 3 A table with one comb offset and multiple cyclic shifts to support eight-port SRS with comb-2 is illustrated in accordance with one embodiment.

[0011] Figure 4 An SRS-resource configuration providing comb offset and cyclic shifts for comb-2 structure is illustrated in accordance with some embodiments.

[0012] Figure 5 A table in which two comb offsets and multiple cyclic shifts are used to support eight-port SRS with comb-2 structure is illustrated in accordance with some embodiments.

[0013] Figure 6 A table with multiple comb offsets to support eight-port SRS with comb-4 structure while maintaining the maximum number of cyclic shifts for comb-4 as shown in Figure 2 is illustrated in accordance with some embodiments.

[0014] Figure 7 A table with multiple comb offsets to support eight-port SRS with comb-4 structure while maintaining the maximum number of cyclic shifts for comb-4 as shown in Figure 2 is illustrated in accordance with some embodiments.

[0015] Figure 8 A configuration for implicitly determining the number of comb offsets based on a threshold associated with a comb offset value is illustrated in accordance with some embodiments.

[0016] Figure 9 A configuration for implicitly determining the number of comb offsets based on a threshold associated with a cyclic shift value is illustrated in accordance with some embodiments.

[0017] Figure 10 A flowchart of a method of a UE according to embodiments herein is illustrated.

[0018] Figure 11 A flowchart of a method for a network node according to embodiments herein is illustrated.

[0019] Figure 12 An example architecture of a wireless communication system according to embodiments disclosed herein is illustrated.

[0020] Figure 13 A system for performing signaling between a wireless device and a network device according to embodiments disclosed herein is illustrated. DETAILED DESCRIPTION

[0021] Various embodiments are described with reference to a user equipment (UE). However, references to a UE are provided for illustrative purposes only. Example embodiments can be used with any electronic component that can establish a connection with a network and is configured with hardware, software, and / or firmware for exchanging information and data with the network. Thus, a UE as described herein is used to represent any appropriate electronic component.

[0022] Many wireless communication standards provide for the use of known signals (e.g., pilots or reference signals) for a variety of purposes, such as synchronization, measurement, equalization, control, etc. For example, in cellular wireless communications, a sounding reference signal (SRS) can be used to estimate uplink channel quality. A wireless communication device or mobile device (i.e., a UE) can be able to send an SRS to a base station (e.g., an eNB for LTE and a gNB for NR). The SRS gives information about the combined effects of multipath fading, scattering, Doppler, and power loss of the transmitted signal.

[0023] Using the SRS, a base station can estimate channel quality and manage resources accordingly. For example, since a reference signal includes data known to both the transmitter and receiver, the receiver can use the reference signal to determine / identify various characteristics of the communication channel. This is often referred to as channel estimation, which is used in many high-end wireless communications such as LTE and 5G-NR communications. The known channel properties of a communication link in wireless communications are referred to as channel state information (CSI), which provides information indicative of the combined effects of, for example, scattering, fading, and power decay with distance. The CSI enables adaptation of the transmission to the current channel conditions, which can be used to enable reliable communication at high data rates in multi-antenna systems.

[0024] Generally, multiple antenna systems use precoding to improve communications. Precoding is an extension of beamforming that supports multi-stream (or multi-layer) transmission of multiple antennas for wireless communications and is used to control differences in signal properties between respective signals transmitted from multiple antennas by modifying the signals transmitted from each antenna according to a precoding matrix. In a sense, precoding can be thought of as a process of cross-coupling signals before transmission (in a closed loop operation) to equalize demodulation performance of the layers. The precoding matrix is typically selected from a codebook that defines multiple precoding matrix candidates, where the precoding matrix candidate is typically selected according to a desired level of performance based on any of a number of different factors, such as a current system configuration, a communication environment, and / or feedback information from a receiver that receives the transmitted signals.

[0025] The feedback information can be used to select a precoding matrix candidate by defining the same codebook at both the transmitter and the receiver and using the feedback information from the receiver as an indication of a preferred precoding matrix. Similarly, the feedback information can be used to select a preferred port for UE transmission.

[0026] SRS design can include symbol location, repetition, comb, and cyclic shift. In NR Release 15 (Rel-15), a design for SRS was outlined. In Rel-15, SRS can only be transmitted in the last 6 symbols of each slot. In addition, SRS can be repeated up to four symbols, and SRS supports comb 2 / 4.

[0027] NR Release 16 (Rel-16) provides enhancements to SRS for Rel-15. In Rel-16, SRS can be transmitted in any symbol in a slot. In addition, SRS supports repetition using 8 and 12 symbols.

[0028] NR Release 17 (Rel-17) provides further enhancements to SRS. For example, Rel-17 supports RB-level partial frequency sounding (RPFS). For RPFS, Rel-17 supports starting PRB location hopping. Rel-17 also supports SRS repetition with 10 / 14 symbols. In addition, Rel-17 supports comb 8. For comb 8, Rel-17 supports up to 6 cyclic shifts (CS).

[0029] In current NR specifications, SRS supports at most 4 ports. It can be desirable to support more than four ports. For example, embodiments herein can support 8 transmissions uplink that require SRS with 8 ports. Thus, embodiments can specify uplink (UL) demodulation reference signal (DMRS), SRS, SRS resource indicator (SRI), and transmit precoder matrix indicator (TPMI) (including codebook) enhancements to enable 8 Tx operation to support per-UE 4 and more layers in UL targeting CPE / FA / vehicle / industrial device.

[0030] For 8-port SRS resources in a SRS resource set with usage of “codebook” or “antennaSwitching,” embodiments can support the following when using legacy schemes (repetition, frequency hopping, partial sounding, or a combination thereof) to map 8 ports onto one or more OFDM symbols. For comb-2, the wireless communication system can support 1 and 2 comb offsets. For comb-4, the wireless communication system can support 2 and 4 comb offsets. For comb-8, the wireless communication system can support 4 comb offsets.

[0031] Some embodiments herein address detailed designs for supporting 8-port SRS using different number of comb offsets. The number of comb offsets within the design can include: comb-2 design, comb-4 design, and switching between different number of comb offsets.

[0032] Figure 1 SRS sequence mapping for transmission 100 is illustrated. As shown, transmission 100 includes a plurality of resource elements (REs) (e.g., first RE 102, second RE 104, third RE 106, and fourth RE 108). An RE is a frequency-time unit to which an SRS sequence is mapped. Transmission 100 also includes a plurality of physical resource blocks (PRBs) (e.g., PRB1 110 and PRB2 112) that include a plurality of contiguous REs. The SRS sequence can support a length of 6, 12, 18, 24, and any sequence greater than or equal to 36.

[0033] To support multiple ports and UEs, a comb structure for transmission 100 can be used. An SRS sequence can be mapped to frequency domain resources (e.g., first RE 102, second RE 104, third RE 106, and fourth RE 108) with a comb structure. NR currently supports comb-2, 4, and 8 for SRS. A comb-2 structure would be a case where SRS is transmitted every other RE. Figure 1A comb 4 structure is illustrated. As shown, in the comb 4 structure, the SRS sequence is transmitted every four resource elements. This provides four possible comb offsets 114. The comb offset indicates the starting frequency of the comb structure for the SRS sequence. Similarly, an 8 comb structure would have the SRS transmitted once every eight resource elements. Transmitting according to the comb structure allows for the transmission of SRS sequences from the same UE or different UEs without interfering with other SRS sequences. A comb N (N = 2 / 4 / 8) subsamples the REs by a factor of N, and different comb offsets are orthogonal because they do not overlap in frequency.

[0034] Another way to transmit SRS without interfering with other SRS transmissions is to apply multiple cyclic shift sequences on top of the same SRS sequence. Cyclic shifting allows for multiple transmissions on the same frequency REs by overlapping orthogonal sequences. Thus, a wireless communication system can use comb structures and cyclic shifting to increase its capacity. A cyclic shift sequence of length M can have M orthogonal sequences. Thus, a cyclic shift of length M can be used to create M orthogonal SRS ports using the same SRS comb offset and the same SRS sequence. The cyclic shift sequence length M can be a function of the comb size N.

[0035] Figure 2 A table 200 is illustrated that indicates the maximum number of cyclic shifts as a function of the comb structure specified by the NR standard. For each comb structure, there is a defined number of cyclic shifts in the NR standard. This determines how many SRS modes can be used. For example, for a comb 2 structure there can be eight cyclic shifts, resulting in 16 (i.e., 2 ports or UEs that can be supported. As shown, in some embodiments, comb 2 has a maximum of 8 cyclic shifts, comb 4 has a maximum of 12 cyclic shifts, and comb 8 has a maximum of 6 cyclic shifts.

[0036] However, one of the problems in supporting more than four ports is how to select the cyclic shifts currently. The cyclic shifts are selected so that the cyclic shifts have equal distance between the cyclic shifts. This requirement of equal distance can limit the support of four or more ports. For example, four ports can be supported for comb 2 and comb 4 because four can be evenly divided into the maximum number of cyclic shifts (8 and 12). However, four ports cannot be evenly divided into the six cyclic shifts in comb 8. Similarly, eight ports cannot be supported by comb 4 or comb 8 with a single comb offset.

[0037] Some embodiments herein use multiple SRS comb offsets to support more than four ports. For example, Figure 3 and Figure 5 to Figure 7 ​It is illustrated how multiple SRS comb offsets can be used to support eight ports.

[0038] Figure 3 It is illustrated a table 300 with one comb offset 302 and multiple cyclic shifts 304 that supports 8-port SRS with comb-2 according to one embodiment. The table 300 provides a mapping between SRS ports 306, cyclic shifts 304, and comb offsets 302. The port indices in the SRS port column can be arranged based on the configuration (e.g., port 7 can be aligned with the first row).

[0039] The illustrated embodiment maintains the maximum number of cyclic shifts for comb-2 (e.g., the maximum cyclic shift for comb-2 is 8) as shown. Figure 2 The variable k_TC in the comb offset column is the comb offset value from the SRS-resource configuration. Similarly, the variable n_CS in the cyclic shift column is used to define the cyclic shifts 304 and comes from the SRS-resource configuration. For example, Figure 4 It is illustrated an SRS-resource configuration 406 that provides comb offsets 402 and cyclic shifts 404 for a comb-2 structure.

[0040] Returning to Figure 3 , to support 8-port SRS, the illustrated embodiment uses one comb offset 302. For the comb offset 302, the UE transmits SRS on 8 ports. The SRS for each port is transmitted on a different cyclic shift. According to some embodiments, the cyclic shifts 304 for each port are defined in the cyclic shift column. The illustrated embodiment uses each of the cyclic shifts available for a comb-2 configuration.

[0041] As shown, the table 300 includes eight SRS ports 306 with equally spaced cyclic shifts 304 based on a comb-2 structure for one comb offset 302. Specifically, ports 1000, 1001, 1002, 1003, 1004, 1005, 1006, and 1007 can be orthogonally transmitted using cyclic shifts n_CS, (n_CS+1) mod 8, (n_CS+2) mod 8, (n_CS+3) mod 8, (n_CS+4) mod 8, (n_CS+5) mod 8, (n_CS+6) mod 8, and (n_CS+7) mod 8, respectively. In this embodiment, the SRS for each port in the two groups of four ports is uniformly sampled across the cyclic shift sequence with a step of one.

[0042] Figure 4An SRS-resource configuration 406 is illustrated in which a network node can use to provide comb offset information and cyclic shift information to a UE. The illustrated SRS-resource configuration 406 provides information for both comb 2 and comb 4. For example, the SRS-resource configuration 406 includes a comb offset 402 and a cyclic shift 404 for comb 2 and a comb offset 408 and a cyclic shift 410 for comb 4.

[0043] While the comb 2 structure is able to support eight SRS ports using one comb offset 302, it can be desirable to use two comb offsets. For example, certain channels can be frequency selective or have large delay spreads, and using each of the cyclic shift sequences without gaps can result in interference. Figure 5 An embodiment is illustrated in which both comb offsets of the comb 2 structure are used to support 8-port SRS.

[0044] Figure 5 A table 500 is illustrated in which two comb offsets 502 and multiple cyclic shifts 504 are used to support 8-port SRS with a comb 2 structure, according to some embodiments. The table 500 provides a mapping between SRS ports 506, cyclic shifts 504, and comb offsets 502. The port index in the SRS port column can be arranged based on the configuration (e.g., port 7 can be aligned with the first row).

[0045] The illustrated embodiment maintains the maximum number of cyclic shifts for comb 2 (e.g., the maximum cyclic shift for comb 2 is 8) as shown. Figure 2 The variable k TC in the comb offset column is the comb offset value from the SRS-resource configuration. Similarly, the variable n CS in the cyclic shift column is used to define the cyclic shifts 504 and comes from the SRS-resource configuration.

[0046] To support 8-port SRS, the illustrated embodiment uses two comb offsets 502, and for each comb offset, the UE transmits SRS on 4 ports. In this embodiment, the SRS for each of the two sets of four ports is uniformly sampled across the cyclic shift sequence in steps of two.

[0047] For example, as shown, table 500 includes eight SRS ports 506 with equidistantly spaced cyclic shifts 504 of two comb offsets 502 using a comb-2 structure. Specifically, ports 1000, 1002, 1004, and 1006 are located in comb offset k TC. Further, ports 0, 2, 4, and 6 can be transmitted orthogonally using cyclic shifts n CS, (n CS+2) mod 8, (n CS+4) mod 8, and (n CS+6) mod 8, respectively. The remaining four ports can be transmitted in different comb offsets to avoid interference. For example, in the illustrated embodiment, ports 1001, 1003, 1005, and 1007 are located in comb offset (k TC+1) mod 2. Further, ports 1001, 1003, 1005, and 1007 can be transmitted orthogonally using cyclic shifts n CS, (n CS+2) mod 8, (n CS+4) mod 8, and (n CS+6) mod 8, respectively.

[0048] Figure 6 Table 600 is illustrated with multiple comb offsets 602 for supporting 8-port SRS with a comb-4 structure while maintaining the maximum number of cyclic shifts for comb-4 (e.g., the maximum cyclic shift for comb-4 is 12) as shown. Figure 2 The variable K TC in the comb offset 602 column is the comb offset from the SRS-ResourceConfig. Similarly, the variable n CS in the cyclic shift 604 column is the cyclic shift from the SRS-ResourceConfig. For example, Figure 4 An SRS-ResourceConfig 406 is illustrated that provides comb offsets 408 and cyclic shifts 410 of a comb-4 structure. The port indices in the SRS ports 606 column can be arranged based on the configuration (e.g., port 1007 can be aligned with the first row).

[0049] To support 8-port SRS, the illustrated embodiment uses two comb offsets 602 and, for each comb offset, the UE transmits SRS on 4 ports. Thus, while the maximum 12 cyclic shifts for comb-4 (from table 200) cannot be evenly divisible by 8 ports, the embodiment splits the ports into two comb offsets 602 to form two groups of 4 ports that can evenly divide the 12 cyclic shifts.

[0050] As shown in the figure, Table 600 includes eight SRS ports 606 with equidistant cyclic shifts 604 using two comb offsets 602 employing a comb tooth 4 structure. Specifically, ports 1000, 1002, 1004, and 1006 are located in comb offset k_TC. Furthermore, ports 1000, 1002, 1004, and 1006 can be transmitted orthogonally using cyclic shifts (n_CS+0) mod 12, (n_CS+3) mod 12, (n_CS+6) mod 12, and (n_CS+9) mod 12, respectively. The remaining four ports can be transmitted in different comb offsets to avoid interference. In some embodiments, the comb offset is selected such that the transmissions are evenly spaced along the available frequency resource elements. For example, in the illustrated embodiment, ports 1001, 1003, 1005, and 1007 are located in comb offset (k_TC + 2) mod 4. In addition, cyclic shifts (n_CS+0) mod 12, (n_CS+3) mod 12, (n_CS+6) mod 12 and (n_CS+9) mod 12 can be used to transmit ports 1001, 1003, 1005 and 1007 orthogonally.

[0051] In this implementation, the SRS for each of the four ports in two groups is uniformly sampled with a step-size three-span cyclic shift sequence. Furthermore, the two groups have a uniform distance between the comb shifts (e.g., these groups are shifted with a coefficient of two).

[0052] Figure 7 Table 700 is illustrated with multiple comb offsets 702, which are used to support an 8-port SRS with a comb tooth 4 structure, while maintaining... Figure 2 The maximum number of cyclic shifts for comb tooth 4 is shown (e.g., the maximum cyclic shift for comb tooth 4 is 12). The variable K_TC in column 702 is the comb offset from the SRS-resource configuration. Similarly, the variable n_CS in column 704 is the cyclic shift from the SRS-resource configuration. The port indices in column 706 of the SRS ports can be arranged based on the configuration (e.g., port 1007 can be aligned with the first row).

[0053] To support 8-port SRS, the illustrated implementation uses four comb offsets 702, and for each comb offset, the UE transmits SRS on 2 ports. Therefore, although the maximum 12 cyclic shifts of the comb teeth 4 (from Table 200) cannot be evenly divided among the 8 ports, the implementation splits the ports into four comb offsets 702 to form four groups of 2 ports that can be evenly divided into 12 cyclic shifts.

[0054] As shown, the table 700 includes eight SRS ports 706 with equidistantly spaced cyclic shifts 704 of four comb offsets 702 using a comb-4 structure. Specifically, ports 1000 and 1004 are located in comb offset k TC. Further, ports 1000 and 1004 are transmitted orthogonally using cyclic shifts n CS and (n CS + 6) mod 12, respectively. In the illustrated embodiment, ports 1001 and 1005 are located in comb offset (k TC + 1) mod 4. Further, ports 1001 and 1005 are transmitted orthogonally using cyclic shifts n CS and (n CS + 6) mod 12, respectively. In the illustrated embodiment, ports 1002 and 1006 are located in comb offset (k TC + 2) mod 4. Further, ports 1002 and 1006 are transmitted orthogonally using cyclic shifts n CS and (n CS + 6) mod 12, respectively. In the illustrated embodiment, ports 1003 and 1007 are located in comb offset (k TC + 3) mod 4. Further, ports 1003 and 1007 are transmitted orthogonally using cyclic shifts n CS and (n CS + 6) mod 12, respectively. In this embodiment, the SRS for each port in the four groups of two ports are uniformly sampled across the cyclic shift sequence with a step size of three.

[0055] In some embodiments, for 8-port SRS, multiple comb designs can be supported. For example, a wireless communication system can support two of the designs shown in Figure 3 and Figure 5 to support 8-port SRS with comb-2. Further, a wireless communication system can support two of the designs shown in Figure 6 and Figure 7 to support 8-port SRS with comb-4. Thus, in such embodiments, a UE determines which 8-port SRS configuration to use for SRS transmission.

[0056] To support 8-port SRS, when a particular comb size (e.g., comb-2 / 4) can utilize different numbers of comb offsets to support 8-port SRS, the following are options for configuring the actual number of comb offsets for 8-port SRS. In some embodiments, a network node can explicitly configure a UE which 8-port SRS configuration to use. For example, a network node can explicitly configure the number of comb offsets through radio resource control (RRC).

[0057] For example, a network node can transmit an SRS-ResourceConfig to a UE. Within the SRS-ResourceConfig information element, the network node can define the comb offset values and the cyclic shift values as shown in Figure 4As shown. Additionally, the SRS-Resource Configuration Information element may include an indication of which 8-port SRS design is intended for comb teeth 2 and 4. For example, the SRS-Resource Configuration Information element may include the actual number of comb offsets to be used for the 8-port SRSs used for comb teeth 2 and 4.

[0058] In some implementations, the number of comb offsets used for 8-port SRS may not be explicitly defined by the network node. In these implementations, the UE can determine the number of comb offsets to use for 8-port SRS based on implicit rules. For example, the UE can determine the number of comb offsets based on the comb offsets configured in the SRS-resource configuration (i.e., combOffset). For example, for comb tooth 2, if the comb offset value is below a threshold, the UE can use a two-comb-offset design (e.g., ...). Figure 5 (See Table 500), otherwise if the comb offset value is higher than the threshold, the UE can use a comb offset design (e.g., Figure 3 (See Table 300). Similarly, in some implementations, the UE can determine the number of comb offsets based on the configured cyclic shift (i.e., cyclicShift).

[0059] It may be desirable to change which 8-port SRS design to use based on the dynamic distribution of the wireless communication system. In some implementations, to support 8-port SRS, network nodes can explicitly configure the number of comb offsets used for 8-port SRS when a particular comb size (e.g., 2 / 4 comb teeth) can utilize different numbers of comb offsets to support 8-port SRS. For example, a Media Access Control (MAC) element (CE) or a Downlink Control Indicator (DCI) can be used to change the comb offset. The MAC CE can be used to update the number of comb offsets. The DCI can be used to indicate the number of comb offsets. For example, the DCI can be used to indicate the number of comb offsets used for aperiodic SRS resources.

[0060] Network nodes can dynamically change the number of comb offsets based on channel distribution. For example, if the channel delay distribution is large, the network node can be configured with a larger number of comb offsets. If the channel delay distribution is small, the network node can use a smaller number of comb offsets.

[0061] Figure 8 An example of a possible implementation for implicitly determining the number of comb offsets based on a threshold associated with the comb offset value is illustrated. The comb offset value can be set using the `combOffset` field in the SRS-resource configuration. The threshold can be used to implicitly switch between using different numbers of comb offsets for an 8-port SRS. For example, the threshold can be used to determine whether a first comb design 802 should be used or whether a second comb design 804 should be used.

[0062] To support 8-port SRS, when a particular comb size (e.g., comb-2 / 4) can utilize different numbers of comb offsets to support 8-port SRS, if an implicit configuration of the number of comb offsets is used for 8-port SRS, the UE can determine the number of comb offsets based on a threshold. If combOffset is used, a threshold can be defined for combOffset. The threshold can be denoted as X. When configured as combOffset < X, a first number of comb offsets can be used. When configured as combOffset >= X, another number of comb offsets can be used. When comb-2 is used and the system supports both 1 comb offset and 2 comb offsets for 8-port SRS, X can be set to one.

[0063] In the illustrated embodiment, the threshold is set to one. If the comb offset value is less than the threshold (e.g., combOffset = 0), a first comb design 802 is used. The first comb design 802 uses one comb offset and eight cyclic shifts, as discussed with reference to FIG. 2. Figure 3 If the comb offset value is greater than or equal to the threshold (e.g., combOffset = 1), a second comb design 802 is used. The second comb design 802 uses two comb offsets and four cyclic shifts, as discussed with reference to FIG. 2. Figure 5

[0064] In the illustrated embodiment, the comb size is two. However, a similar threshold can be used to support a comb size of four. For example, the threshold can be set to two. If the comb offset value is less than two, the comb design described with reference to FIG. 2 can be used. If the comb offset value is greater than or equal to two, the comb design described with reference to FIG. 3 can be used. Figure 6 Figure 7

[0065] Figure 9 One possible embodiment for implicitly determining the number of comb offsets based on a threshold associated with a cyclic shift value is illustrated. The cyclic shift value can be set using the cyclicShift field in the SRS-ResourceConfig. The threshold can be used to implicitly switch between using different numbers of comb offsets for 8-port SRS. For example, the threshold can be used to determine whether a first comb design 902 should be used or whether a second comb design 904 should be used.

[0066] ​​​To support 8-port SRS, when a particular comb size (e.g., comb-2 / 4) can utilize different numbers of comb offsets to support 8-port SRS, if an implicit configuration of the number of comb offsets is used for 8-port SRS, the UE can determine the number of comb offsets based on a threshold. The threshold can be defined for cyclicShift if cyclicShift is used. The threshold can be denoted as X. When configured as cyclicShift < X, a first number of comb offsets can be used. When configured as cyclicShift >= X, another number of comb offsets can be used. When comb-2 is used and the system supports both 1 comb offset and 2 comb offsets for 8-port SRS, X can be set to four.

[0067] In the illustrated embodiment, the threshold is set to four for comb-2. If the cyclic shift value is less than the threshold (e.g., cyclicShift = 0, 1, 2, or 3), a first comb design 902 is used. The first comb design 902 uses one comb offset and eight cyclic shifts, as discussed with reference to FIG. 6. Figure 3 If the cyclic shift value is greater than or equal to the threshold (e.g., cyclicShift = 4, 5, 6, or 7), a second comb design 902 is used. The second comb design 902 uses two comb offsets and four cyclic shifts, as discussed with reference to FIG. 7. Figure 5

[0068] In the illustrated embodiment, the comb size is two. However, a similar threshold can be used to support a comb size of four. For example, the threshold can be set to six. If the cyclic shift value is less than six, the comb design described with reference to FIG. 6 can be used. Figure 6 If the cyclic shift value is greater than or equal to six, the comb design described with reference to FIG. 7 can be used. Figure 7

[0069] ​​In some embodiments, when the system utilizes multiple numbers of comb offsets to support 8-port SRS, a restriction can be configured. The restriction can simplify implementation and make the number of comb offsets for SRS resources more uniform. In some embodiments, all of the SRS resources in the same SRS-resource set can have the same number of comb offsets to support 8-ports. For example, if a first SRS-resource is configured to use one comb offset, all other SRS-resources in the same SRS-resource set will use one comb offset. In some embodiments, all SRS-resources in the same active uplink (UL) bandwidth part (BWP) can have the same number of comb offsets to support 8-ports. In such embodiments, even if the SRS-resources are in different sets, if they are on the same active UL BWP, the SRS-resources will use the same number of comb offsets to support 8-port SRS. In some embodiments, all SRS-resources in the same serving cell can have the same number of comb offsets to support 8-ports.

[0070] Figure 10 A flowchart of a method 1000 of a UE according to embodiments herein is illustrated. The method 1000 comprises receiving 1002, from a network node, an SRS-resource comprising configuration details for SRS for eight ports using a comb size, the comb size utilizing a first number of comb offsets and a second number of comb offsets to support SRS for eight ports.

[0071] The method 1000 further comprises determining 1004 whether to use the first number of comb offsets or the second number of comb offsets for SRS transmission from the eight ports for the SRS-resource.

[0072] The method 1000 further comprises transmitting 1006, to the network node, SRS transmission via the eight ports using the determined first number of comb offsets or the second number of comb offsets.

[0073] In some embodiments of the method 1000, the SRS-resource comprises a field indicating a number of comb offsets that the UE is to use for SRS for the comb size, and determining whether to use the first number of comb offsets or the second number of comb offsets is based on the field. Some such embodiments further comprise receiving a MAC-CE or DCI comprising an update to the number of comb offsets.

[0074] In some embodiments of the method 1000, the SRS-resource includes a comb offset value and a cyclic shift value, where determining whether to use the first number of comb offsets or the second number of comb offsets includes comparing the comb offset value or the cyclic shift value to a threshold, where the second number of comb offsets is used when the comb offset value or the cyclic shift value is less than the threshold, and the second number of comb offsets is used when the comb offset value or the cyclic shift value is greater than or equal to the threshold.

[0075] In some embodiments of the method 1000, for a comb size of two, the first number of comb offsets is one comb offset and the second number of comb offsets is two comb offsets, where for one comb offset, eight cyclic shifts are used for transmitting the SRS transmission, each cyclic shift corresponding to one of the eight ports, and where for two comb offsets, four cyclic shifts are used for transmitting the SRS transmission per comb offset, where the eight ports are evenly divided between the two comb offsets.

[0076] In some embodiments of the method 1000, for a comb size of four, the first number of comb offsets is two comb offsets and the second number of comb offsets is four comb offsets, where for two comb offsets, four cyclic shifts are used for transmitting the SRS transmission per comb offset, where the eight ports are evenly divided between the two comb offsets, and where for four comb offsets, two cyclic shifts are used for transmitting the SRS transmission per comb offset, where the eight ports are evenly divided between the four comb offsets.

[0077] In some embodiments of the method 1000, all SRS resources in the same SRS-resource set use the same number of comb offsets to support SRS for the eight ports.

[0078] In some embodiments of the method 1000, all SRS resources in the same active UL BWP use the same number of comb offsets to support SRS for the eight ports.

[0079] In some embodiments of the method 1000, all SRS resources in the same serving cell should use the same number of comb offsets to support SRS for the eight ports.

[0080] Embodiments contemplated herein include an apparatus comprising means for performing one or more elements of the method 1000. The apparatus can be, for example, an apparatus of a UE (such as the wireless device 1302 (UE), as described herein).

[0081] Embodiments contemplated herein include one or more non-transitory computer- readable media comprising instructions for causing an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of the method 1000. Such non-transitory computer-readable media can be, for example, a memory of a UE (such as the memory 1306 of the wireless device 1302 (UE), as described herein).

[0082] Embodiments contemplated herein include an apparatus comprising logic, modules, or circuitry to perform one or more elements of the method 1000. The apparatus can be, for example, an apparatus of a UE (such as the wireless device 1302 (UE), as described herein).

[0083] Embodiments contemplated herein include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of the method 1000. The apparatus can be, for example, an apparatus of a UE (such as the wireless device 1302 (UE), as described herein).

[0084] Embodiments contemplated herein include a signal as described in or related to one or more elements of the method 1000.

[0085] Embodiments contemplated herein include a computer program or computer program product comprising instructions that, when executed by a processor, will cause the processor to perform one or more elements of the method 1000. The processor can be a processor of a UE (such as the processor 1304 of the wireless device 1302 (UE), as described herein). The instructions can be, for example, located in the processor and / or on a memory of the UE (such as the memory 1306 of the wireless device 1302 (UE), as described herein).

[0086] Figure 11 A flow diagram of a method 1100 of a network node in accordance with embodiments herein is illustrated. The method 1100 includes encoding 1102 an SRS-resource comprising configuration details for eight ports of a UE using a comb size of SRS, the comb size supporting SRS for the eight ports with a first number of comb offsets and a second number of comb offsets, and the SRS-SRS-resource comprising an indication of whether the UE is to use the first number of comb offsets or the second number of comb offsets for SRS transmissions from the eight ports for the SRS-resource.

[0087] The method 1100 also includes transmitting 1104, to the UE, an SRS-resource and triggering SRS transmission.

[0088] The method 1100 also includes receiving 1106, from the UE, SRS transmission via eight ports using the determined first number of comb offsets or the second number of comb offsets.

[0089] In some embodiments of the method 1100, the SRS-resource includes a field that explicitly indicates a number of comb offsets that the UE is to use for SRS for a comb size. Some such embodiments also include transmitting a MAC-CE or DCI that includes an update to the number of comb offsets.

[0090] In some embodiments of the method 1100, the SRS-resource includes a comb offset value and a cyclic shift value, where an indication of whether the UE is to use a first number of comb offsets or a second number of comb offsets is based on a comparison of the comb offset value or the cyclic shift value to a threshold, the first number of comb offsets is used when the comb offset value or the cyclic shift value is less than the threshold, and the second number of comb offsets is used when the comb offset value or the cyclic shift value is greater than or equal to the threshold.

[0091] In some embodiments of the method 1100, for a comb size of two, the first number of comb offsets is one comb offset and the second number of comb offsets is two comb offsets, where for one comb offset eight cyclic shifts are used for SRS transmission, each cyclic shift corresponding to one of the eight ports, and where for two comb offsets four cyclic shifts are used for SRS transmission per comb offset, where the eight ports are evenly divided between the two comb offsets.

[0092] In some embodiments of the method 1100, for a comb size of four, the first number of comb offsets is two comb offsets and the second number of comb offsets is four comb offsets, where for two comb offsets four cyclic shifts are used for SRS transmission per comb offset, where the eight ports are evenly divided between the two comb offsets, and where for four comb offsets two cyclic shifts are used for SRS transmission per comb offset, where the eight ports are evenly divided between the four comb offsets.

[0093] In some embodiments of the method 1100, all SRS resources in a same SRS-resource set use a same number of comb offsets to support SRS for the eight ports.

[0094] In some embodiments of the method 1100, all SRS resources in a same active UL BWP use a same number of comb offsets to support SRS for the eight ports.

[0095] In some embodiments of the method 1100, all SRS resources in the same serving cell should use the same number of comb offsets to support SRS for eight ports.

[0096] Embodiments contemplated herein include an apparatus comprising means for performing one or more elements of the method 1100. The apparatus can be, for example, an apparatus of a base station, such as the network equipment 1318 (base station), as described herein.

[0097] Embodiments contemplated herein include one or more non-transitory computer- readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of the method 1100. The non-transitory computer-readable medium can be, for example, a memory of a base station, such as the memory 1322 of the network equipment 1318 (base station), as described herein.

[0098] Embodiments contemplated herein include an apparatus comprising logic, modules, or circuitry for performing one or more elements of the method 1100. The apparatus can be, for example, an apparatus of a base station, such as the network equipment 1318 (base station), as described herein.

[0099] Embodiments contemplated herein include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions, which, when executed by the one or more processors, cause the one or more processors to perform one or more elements of the method 1100. The apparatus can be, for example, an apparatus of a base station, such as the network equipment 1318 (base station), as described herein.

[0100] Embodiments contemplated herein include a signal as described in or related to one or more elements of the method 1100.

[0101] Embodiments contemplated herein include a computer program or computer program product that comprises instructions, wherein execution of the program by a processing element will cause the processing element to perform one or more elements of the method 1100. The processing element can be a processor of a base station, such as the processor 1320 of the network equipment 1318 (base station), as described herein. The instructions can be, for example, located in the processor and / or the memory of the base station, such as the memory 1122 of the network equipment 1118 (base station), as described herein.

[0102] Figure 12An example architecture of a wireless communication system 1200 according to embodiments disclosed herein is illustrated. The following description is provided for an example wireless communication system 1200 that operates in connection with LTE system standards and / or 5G or NR system standards provided by 3GPP Technical Specifications.

[0103] As shown, the wireless communication system 1200 includes UE 1202 and UE 1204 (although an arbitrary number of UEs can be used). In this example, the UE 1202 and the UE 1204 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connected to one or more cellular networks) but can also include any mobile or non-mobile computing devices configured for wireless communication. Figure 12

[0104] The UE 1202 and the UE 1204 can be configured to communicatively couple with a RAN 1206. In embodiments, the RAN 1206 can be an NG-RAN, an E-UTRAN, etc. The UE 1202 and the UE 1204 utilize connections (or channels) with the RAN 1206, illustrated as connections 1208 and 1210, respectively, where each connection (or channel) includes a physical communications interface. The RAN 1206 can include one or more base stations (such as base stations 1212 and 1214) that implement the connections 1208 and 1210.

[0105] In this example, the connections 1208 and 1210 are air interfaces that implement the wireless communication coupling between the UEs 1202 and 1204 and the RAN 1206, and can be implemented using any suitable wireless communication technology.

[0106] In some embodiments, the UEs 1202 and 1204 can also communicate directly using a sidelink interface 1216. The UE 1204 is shown to be configured to access an access point (shown as AP 1218) via connection 1220. In turn, the AP 1218 can provide connectivity to a wider area network (WAN), such as the Internet, via a CN 1224. The connection 1220 can be a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, according to an embodiment. In another embodiment, the connection 1220 can be a physical connection, such as a cable. ® In this example, the AP 1218 can not be connected to another network (e.g., the Internet) through the CN 1224.

[0107] ​In embodiments, the UEs 1202 and 1204 can be configured to communicate using orthogonal frequency division multiplexing (OFDM) communication signals with each other or with the base stations 1212 and / or 1214 over a multicarrier communication channel in accordance with various communication techniques, such as, but not limited to, an orthogonal frequency division multiple access (OFDMA) communication technique (e.g., for downlink communications) or a single carrier frequency division multiple access (SC-FDMA) communication technique (e.g., for uplink and ProSe or sidelink communications), although the scope of the embodiments is not limited in this respect. The OFDM signals can comprise a plurality of orthogonal subcarriers.

[0108] In some embodiments, all or a portion of base station 1212 or base station 1214 can be implemented as one or more software entities running on a server computer(s) as part of a virtual network. Additionally, or in other embodiments, base station 1212 or base station 1214 can be configured to communicate with each other via interface 1222. In embodiments where the wireless communication system 1200 is an LTE system (e.g., where CN 1224 is an EPC), interface 1222 can be an X2 interface. The X2 interface can be defined between two or more base stations (e.g., two or more eNBs, etc.) that connect to the EPC or between two eNBs that connect to the EPC. In embodiments where the wireless communication system 1200 is a NR system (e.g., where CN 1224 is a 5GC), interface 1222 can be an Xn interface. The Xn interface is defined between two or more base stations (e.g., two or more gNBs, etc.) that connect to the 5GC, between a base station 1212 (e.g., gNB) and an eNB that connect to the 5GC, and / or between two eNBs that connect to the 5GC (e.g., CN 1224).

[0109] The RAN 1206 is shown to be communicably coupled to a CN 1224. The CN 1224 can include one or more network elements 1226 that are configured to provide various data and telecommunications services to customers / subscribers (e.g., users of UEs 1202 and 1204) who are connected to the CN 1224 via the RAN 1206. The components of the CN 1224 can be implemented in one physical device or separate physical devices including components to read and execute instructions from a machine- or computer-readable medium (e.g., a non-transitory machine-readable storage medium).

[0110] In embodiments, the CN 1224 can be an EPC and the RAN 1206 can be connected with the CN 1224 via an S1 interface 1228. In embodiments, the S1 interface 1228 can be split into two parts, an S1 user plane (S1-U) interface, which carries traffic data between the base stations 1212, 1214 and the serving gateway (S-GW), and the S1-MME, which is a signaling interface between the base stations 1212, 1214 and the mobile management entity (MME).

[0111] In embodiments, the CN 1224 can be a 5GC and the RAN 1206 can be connected with the CN 1224 via an NG interface 1228. In embodiments, the NG interface 1228 can be split into two parts, an NG user plane (NG-U) interface, which carries traffic data between the base stations 1212, 1214 and user plane functions (UPFs), and the S1 control plane (NG-C) interface, which is a signaling interface between the base stations 1212, 1214 and the access and mobility management function (AMF).

[0112] Generally, the application server 1230 can be an element offering applications that use Internet Protocol (IP) bearer resources with the CN 1224. The application server 1230 can also be configured to support one or more communication services (e.g., VoIP sessions, group communication sessions, etc.) for UEs 1202 and 1204 via the CN 1224. The application server 1230 can communicate with the CN 1224 through the IP communication interface 1232.

[0113] Figure 13 A system 1300 for performing signaling 1334 between a wireless device 1302 and a network device 1318 is illustrated in accordance with the embodiments disclosed herein. The system 1300 can be a portion of a wireless communications system as described herein. The wireless device 1302 can be, for example, a UE of the wireless communications system. The network device 1318 can be, for example, a base station (e.g., an eNB or gNB) of the wireless communications system.

[0114] The wireless device 1302 can include one or more processors 1304. The processors 1304 can execute instructions to perform various operations of the wireless device 1302, as described herein. The processors 1304 can include one or more baseband processors that are implemented using, for example, a central processing unit (CPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

[0115] The wireless device 1302 can include memory 1306. The memory 1306 can be a non-transitory computer-readable storage medium that stores instructions 1308 (which can include, for example, instructions for execution by the processors 1304). The instructions 1308 can also be referred to as program code or computer programs. The memory 1306 can also store data used by the processors 1304 and results produced by the processors.

[0116] The wireless device 1302 can include one or more transceivers 1310 that can include radio frequency (RF) transmitter circuits and / or receiver circuits that use antennas 1312 of the wireless device 1302 to facilitate signaling (e.g., signaling 1334) to and / or from the wireless device 1302 with other devices (e.g., network devices 1318) in accordance with a corresponding RAT.

[0117] The wireless device 1302 can include one or more antennas 1312 (e.g., one, two, four, or more). For embodiments with multiple antennas 1312, the wireless device 1302 can take advantage of spatial diversity of these multiple antennas 1312 to transmit and / or receive multiple different data streams on the same time-frequency resources. This behavior can be referred to as, for example, multiple-input multiple-output (MIMO) behavior (referring to the multiple antennas used at each of the transmitting device and the receiving device to implement this aspect). MIMO transmission by the wireless device 1302 can be implemented according to precoding (or digital beamforming) applied to the wireless device 1302 that multiplexes data streams between the antennas 1312 according to known or assumed channel characteristics such that each data stream is at an appropriate signal strength relative to other streams and is received at a desired location in space (e.g., the location of the receiver associated with that data stream). Certain embodiments can use single-user MIMO (SU-MIMO) methods (where data streams are all directed to a single receiver) and / or multi-user MIMO (MU-MIMO) methods (where separate data streams can be directed to separate (different) receivers in different locations in space).

[0118] In some implementations with multiple antennas, wireless device 1302 may implement analog beamforming technology, whereby the phase of the signal transmitted by antenna 1312 is relatively adjusted so that the (joint) transmission of antenna 1312 can be directed (this is sometimes referred to as beam control).

[0119] Wireless device 1302 may include one or more interfaces 1314. Interface 1314 can be used to provide input to or from wireless device 1302. For example, wireless device 1302 (UE) may include interface 1314, such as a microphone, speaker, touchscreen, and buttons, to allow users of the UE to input to and / or output to the UE. Other interfaces of such a UE may consist of transmitters, receivers, and other circuitry (e.g., in addition to the transceiver 1310 / antenna 1312 already described), allowing communication between the UE and other devices, and can be configured according to known protocols (e.g., Wi-Fi). ® ,Bluetooth ® (etc.) to perform the operation.

[0120] Wireless device 1302 may include SRS module 1316. SRS module 1316 may be implemented via hardware, software, or a combination thereof. For example, SRS module 1316 may be implemented as a processor, circuitry, and / or instructions 1308 stored in memory 1306 and executed by processor 1304. In some examples, SRS module 1316 may be integrated within processor 1304 and / or transceiver 1310. For example, SRS module 1316 may be implemented via a combination of software components (e.g., software components executed by a DSP or general-purpose processor) and hardware components (e.g., logic gates and circuitry) within processor 1304 or transceiver 1310.

[0121] SRS module 1316 can be used in various aspects of this disclosure, for example, Figure 2 to Figure 10 All aspects. The SRS module 1316 is configured to configure the wireless device 1302 to transmit SRS. The configuration includes determining the number of comb offsets to use when transmitting SRS.

[0122] Network device 1318 may include one or more processors 1320. Processor 1320 is executable instructions to perform various operations of network device 1318 as described herein. Processor 1320 may include one or more baseband processors, which are implemented using, for example, a CPU, DSP, ASIC, controller, FPGA device, another hardware device, firmware device, or any combination thereof configured to perform the operations described herein.

[0123] The network device 1318 can include a memory 1322. The memory 1322 can be a non-transitory computer-readable storage medium that stores instructions 1324 (which can include, for example, computer program instructions, software modules, or embedded logic) that can be executed by the processor 1320. The instructions 1324 can also be referred to as program code or computer programs. The memory 1322 can also store data used by the processor 1320, as well as results (e.g., messages) produced by the processor.

[0124] The network device 1318 can include one or more transceivers 1326 that can include RF transmitter and / or receiver circuits that use the antennas 1328 of the network device 1318 to facilitate signaling (e.g., signaling 1334) to and / or from the network device 1318 with other devices (e.g., the wireless device 1302) in accordance with the corresponding RAT.

[0125] The network device 1318 can include one or more antennas 1328 (e.g., one, two, four, or more). In embodiments with multiple antennas 1328, the network device 1318 can perform MIMO, digital beamforming, analog beamforming, beam steering, etc., as has been described.

[0126] The network device 1318 can include one or more interfaces 1330. The interface 1330 can be used to provide input to and to receive output from the network device 1318. For example, the network device 1318 being a base station can include an interface 1330 consisting of a transmitter, receiver, and other circuitry (e.g., in addition to the transceiver 1326 / antenna 1328 already described) that enables the base station to communicate with other equipment in the core network, and / or to communicate with external networks, computers, databases, etc. for the purpose of operating, managing, and maintaining the base station or other equipment with which the base station is in operable connection.

[0127] The network device 1318 can include an SRS configuration module 1332. The SRS configuration module 1332 can be implemented via hardware, software, or combinations thereof. For example, the SRS configuration module 1332 can be implemented as a processor, circuit, and / or instructions 1324 stored in the memory 1322 and executed by the processor 1320. In some examples, the SRS configuration module 1332 can be integrated within the processor 1320 and / or the transceiver 1326. For example, the SRS configuration module 1332 can be implemented by a combination of software components (e.g., executed by a DSP or a general purpose processor) and hardware components (e.g., logic gates and circuitry) within the processor 1320 or the transceiver 1326.

[0128] The SRS configuration module 1332 can be used in various aspects of the disclosure, for example Figure 2 to Figure 9 andFigure 11 Aspects of the SRS configuration module 1332 are configured to encode and transmit configuration details for SRS.

[0129] For one or more embodiments, at least one of the components set forth in one or more of the preceding figures can be configured to perform one or more operations, techniques, processes, and / or methods as set forth herein. For example, a baseband processor as described herein in connection with one or more of the preceding figures can be configured to operate in accordance with one or more of the examples set forth herein. For another example, circuitry associated with a UE, base station, network element, etc. as described above in connection with one or more of the preceding figures can be configured to operate in accordance with one or more of the examples set forth herein.

[0130] Any of the above-described embodiments can be combined with any other embodiment (or combination of embodiments) unless explicitly stated otherwise. The foregoing description of implementations has provided a few aspects in accordance with the present disclosure. For the purpose of a convenience and adaption for the reader, this description has divided the system and method into sections. However, the reader should be aware that the described aspects can be combined or divided into further aspects. Further, the disclosure can be implemented in a wide variety of ways.

[0131] Embodiments and implementations of the systems and methods described herein can include various operations, which can be embodied in machine-executable instructions to be executed by a computer system. The computer system can include one or more general-purpose or special-purpose computers (or other electronic devices). The computer system can include hardware components, including specific logic for performing the operations; or can include a combination of hardware, software, and / or firmware.

[0132] It will be recognized that the systems described herein include the description of the embodiments. The embodiments can be combined into a single system, partially combined into other systems, divided into multiple systems, or otherwise divided or combined. Further, it is contemplated that parameters, attributes, aspects, etc. of one embodiment can be used in another embodiment. For clarity, these parameters, attributes, aspects, etc. are described in one or more embodiments only and it will be recognized that these parameters, attributes, aspects, etc. can be combined with or substituted for parameters, attributes, aspects, etc. of another embodiment unless specifically stated otherwise.

[0133] It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled in a way to minimize risk of unintentional or unauthorized access or use, and the nature of authorization should be clearly expressed to the users.

[0134] While the foregoing has been described in some detail for purposes of clarity, it will be apparent that certain changes and modifications can be made without departing from the principles thereof. It should be noted that there are many alternative ways of implementing both the processes and apparatuses described herein. Accordingly, the embodiments of the application are to be considered illustrative and not restrictive, and the description is not to be limited to the details given herein, but can be modified within the scope and equivalents of the appended claims.

Claims

1. A method for a user equipment (UE), the method comprising: receiving, from a network node, a sounding reference signal resource (SRS-resource) comprising configuration details for SRS for eight ports using a comb size, the comb size supporting the SRS for the eight ports with a first number of comb offsets and a second number of comb offsets, determining whether to use the first number of comb offsets or the second number of comb offsets for SRS transmissions from the eight ports for the SRS-resource; and transmitting, to the network node, the SRS transmissions via the eight ports using the determined first number of comb offsets or the second number of comb offsets.

2. The method of claim 1, wherein the SRS-resource comprises a field indicating a number of comb offsets the UE is to use for SRS for the comb size; and wherein determining whether to use the first number of comb offsets or the second number of comb offsets is based on the field. receiving a medium access control (MAC) control element (CE) or a downlink control indicator (DCI) comprising an update to a current number of comb offsets.

3. The method of claim 2, further comprising:

4. The method of claim 1, wherein the SRS-resource comprises a comb offset value and a cyclic shift value, wherein determining whether to use the first number of comb offsets or the second number of comb offsets comprises: comparing the comb offset value or the cyclic shift value to a threshold value, wherein the first number of comb offsets is used when the comb offset value or the cyclic shift value is less than the threshold value and the second number of comb offsets is used when the comb offset value or the cyclic shift value is greater than or equal to the threshold value.

5. The method of claim 1, wherein for comb size two, the first number of comb offsets is one comb offset and the second number of comb offsets is two comb offsets, wherein for the one comb offset, eight cyclic shifts are used to transmit the SRS transmissions, each cyclic shift corresponding to one of the eight ports; and wherein for the two comb offsets, four cyclic shifts are used to transmit the SRS transmissions per comb offset, wherein the eight ports are evenly divided between the two comb offsets.

6. The method of claim 1, wherein for comb size four, the first number of comb offsets is two comb offsets and the second number of comb offsets is four comb offsets, wherein for the two comb offsets, four cyclic shifts are used to transmit the SRS transmissions per comb offset, wherein the eight ports are evenly divided between the two comb offsets; and wherein for the four comb offsets, two cyclic shifts are used to transmit the SRS transmissions per comb offset, wherein the eight ports are evenly divided between the four comb offsets. ​ 7. The method of claim 1, wherein all SRS resources in a same SRS-resource set use a same number of comb offsets to support the SRS for the eight ports.

8. The method of claim 1, wherein all SRS resources in a same active uplink (UL) bandwidth part (BWP) use a same number of comb offsets to support the SRS for the eight ports.

9. The method of claim 1, wherein all SRS resources in a same serving cell shall use a same number of comb offsets to support the SRS for the eight ports.

10. An apparatus of a user equipment (UE), the apparatus comprising: a processor; and a memory storing instructions that, when executed by the processor, configure the UE to: receive, from a network node, a sounding reference signal resource (SRS-resource) comprising configuration details for SRS for eight ports using a comb size, the comb size utilizing a first number of comb offsets and a second number of comb offsets to support the SRS for the eight ports, determine whether to use the first number of comb offsets or the second number of comb offsets for SRS transmissions from the eight ports for the SRS-resource; and transmit, to the network node via the eight ports, the SRS transmissions using the determined first number of comb offsets or the second number of comb offsets.

11. The apparatus of claim 10, wherein the SRS-resource comprises a field indicating a number of comb offsets the UE is to use for SRS for the comb size; and wherein determining whether to use the first number of comb offsets or the second number of comb offsets is based on the field.

12. The apparatus of claim 11, wherein the instructions further configure the UE to receive a medium access control (MAC) control element (CE) or a downlink control indicator (DCI) comprising an update to a current number of comb offsets.

13. The apparatus of claim 10, wherein the SRS-resource comprises a comb offset value and a cyclic shift value, compare the comb offset value or the cyclic shift value to a threshold value, wherein the first number of comb offsets is used when the comb offset value or the cyclic shift value is less than the threshold value, and the second number of comb offsets is used when the comb offset value or the cyclic shift value is greater than or equal to the threshold value. wherein determining whether to use the first number of comb offsets or the second number of comb offsets comprises:

14. The apparatus of claim 10, wherein for a comb size of two, the first number of comb offsets is one comb offset and the second number of comb offsets is two comb offsets, wherein for the one comb offset, eight cyclic shifts are used to transmit the SRS transmissions, each cyclic shift corresponding to one of the eight ports; and wherein for the two comb offsets, four cyclic shifts are used to transmit the SRS transmissions, each cyclic shift corresponding to two of the eight ports. ​ wherein for the two comb offsets, four cyclic shifts per comb offset are used to transmit the SRS transmissions, wherein the eight ports are evenly divided between the two comb offsets.

15. The apparatus of claim 10, wherein for a comb size four, the first number of comb offsets is two comb offsets and the second number of comb offsets is four comb offsets, wherein for the two comb offsets, four cyclic shifts per comb offset are used to transmit the SRS transmissions, wherein the eight ports are evenly divided between the two comb offsets; and wherein for the four comb offsets, two cyclic shifts per comb offset are used to transmit the SRS transmissions, wherein the eight ports are evenly divided between the four comb offsets.

16. The apparatus of claim 10, wherein all SRS resources in a same SRS- resource set use a same number of comb offsets to support the SRS for the eight ports.

17. The apparatus of claim 10, wherein all SRS resources in a same active uplink (UL) bandwidth part (BWP) use a same number of comb offsets to support the SRS for the eight ports.

18. The apparatus of claim 10, wherein all SRS resources in a same serving cell shall use a same number of comb offsets to support the SRS for the eight ports.

19. A method for a network node, the method comprising: encoding a sounding reference signal resource (SRS-resource) including configuration details for a sounding reference signal (SRS) for eight ports of a user equipment (UE) using a comb size, the comb size supporting the SRS for the eight ports with a first number of comb offsets and a second number of comb offsets, wherein the SRS-resource includes an indication of whether the UE is to use the first number of comb offsets or the second number of comb offsets for SRS transmissions from the eight ports for the SRS-resource; transmitting the SRS-resource to the UE and triggering the SRS transmissions; and receiving the SRS transmissions from the UE via the eight ports using the determined first number of comb offsets or the second number of comb offsets.

20. The method of claim 19, wherein the SRS-resource includes a field explicitly indicating a number of comb offsets the UE is to use for SRS for the comb size.

21. The method of claim 20, further comprising: transmitting a medium access control (MAC) control element (CE) or a downlink control indicator (DCI) including an update to a current number of comb offsets.

22. The method of claim 19, wherein the SRS-resource includes a comb offset value and a cyclic shift value, wherein the indication of whether the UE is to use the first number of comb offsets or the second number of comb offsets is based on a comparison of the comb offset value or the cyclic shift value to a threshold value, wherein the first number of comb offsets is used when the comb offset value or the cyclic shift value is less than the threshold value, and the second number of comb offsets is used when the comb offset value or the cyclic shift value is greater than or equal to the threshold value.

23. The method of claim 19, wherein for a comb size of two, the first number of comb offsets is one comb offset and the second number of comb offsets is two comb offsets, wherein for the one comb offset, eight cyclic shifts are used for the SRS transmission, each cyclic shift corresponding to one of the eight ports; and wherein for the two comb offsets, four cyclic shifts are used for the SRS transmission per comb offset, wherein the eight ports are evenly divided between the two comb offsets.

24. The method of claim 19, wherein for a comb size of four, the first number of comb offsets is two comb offsets and the second number of comb offsets is four comb offsets, wherein for the two comb offsets, four cyclic shifts are used for the SRS transmission per comb offset, wherein the eight ports are evenly divided between the two comb offsets; and wherein for the four comb offsets, two cyclic shifts are used for the SRS transmission per comb offset, wherein the eight ports are evenly divided between the four comb offsets.

25. The method of claim 19, wherein all SRS resources in a same SRS-resource set use a same number of comb offsets to support the SRS for the eight ports.

26. The method of claim 19, wherein all SRS resources in a same active uplink (UL) bandwidth part (BWP) use a same number of comb offsets to support the SRS for the eight ports.

27. The method of claim 19, wherein all SRS resources in a same serving cell shall use a same number of comb offsets to support the SRS for the eight ports.

28. A network node, the network node comprising: a processor; and a memory storing instructions that, when executed by the processor, configure the network node to: encode a sounding reference signal resource (SRS-resource) comprising configuration details for a sounding reference signal (SRS) for eight ports of a user equipment (UE) using a comb size, the comb size supporting the SRS for the eight ports with a first number of comb offsets and a second number of comb offsets, wherein the SRS-resource comprises an indication of whether the UE is to use the first number of comb offsets or the second number of comb offsets for an SRS transmission from the eight ports for the SRS-resource; transmit the SRS-resource to the UE and trigger the SRS transmission; and receive the SRS transmission from the UE via the eight ports using the determined first number of comb offsets or the second number of comb offsets.

29. The network node of claim 28, wherein the SRS-resource comprises a field explicitly indicating a number of comb offsets that the UE is to use for SRS for the comb size.

30. The network node of claim 29, wherein the instructions further configure the network node to transmit a medium access control (MAC) control element (CE) or a downlink control indicator (DCI) comprising an update to a current number of comb offsets.

31. The network node of claim 28, wherein the SRS-resource comprises a comb offset value and a cyclic shift value, wherein the indication of whether the UE is to use the first number of comb offsets or the second number of comb offsets is based on a comparison of the comb offset value or the cyclic shift value to a threshold, wherein the first number of comb offsets is used when the comb offset value or the cyclic shift value is less than the threshold, and the second number of comb offsets is used when the comb offset value or the cyclic shift value is greater than or equal to the threshold.

32. The network node of claim 28, wherein for comb size two, the first number of comb offsets is one comb offset and the second number of comb offsets is two comb offsets, wherein for the one comb offset, eight cyclic shifts are used for the SRS transmission, each cyclic shift corresponding to one of the eight ports; and wherein for the two comb offsets, four cyclic shifts are used for the SRS transmission per comb offset, wherein the eight ports are evenly divided between the two comb offsets.

33. The network node of claim 28, wherein for comb size four, the first number of comb offsets is two comb offsets and the second number of comb offsets is four comb offsets, wherein for the two comb offsets, four cyclic shifts are used for the SRS transmission per comb offset, wherein the eight ports are evenly divided between the two comb offsets; and wherein for the four comb offsets, two cyclic shifts are used for the SRS transmission per comb offset, wherein the eight ports are evenly divided between the four comb offsets.

34. The network node of claim 28, wherein all SRS resources in a same SRS-resource set use a same number of comb offsets to support the SRS for the eight ports.

35. The network node of claim 28, wherein all SRS resources in a same active uplink (UL) bandwidth part (BWP) use a same number of comb offsets to support the SRS for the eight ports.

36. The network node of claim 28, wherein all SRS resources in a same serving cell are to use a same number of comb offsets to support the SRS for the eight ports.

Images