Enhancements to UE sounding procedure with SRS port grouping

Abstract

The present invention provides a method and system for configuring Sounding Reference Signal (SRS) port grouping in a wireless communication system to eliminate vendor-specific implementation ambiguities and standardize port-to-antenna mapping. The method comprises: transmitting configuration information from a base station to a user equipment (UE) including a parameter indicating whether SRS port grouping is enabled; grouping, by the UE, a plurality of SRS ports by assigning even-numbered ports to a first group and odd-numbered ports to a second group; and associating each port group with corresponding codeword identifiers for downlink data transmission.

Description

[0001] ENHANCEMENTS TO UE SOUNDING PROCEDURE WITH SRS PORT

[0002] GROUPING

[0003] Field of the Invention

[0004] The present invention relates to wireless communication systems, and more particularly to enhancements for user equipment (UE) sounding procedures using sounding reference signal (SRS) port grouping in 5G and beyond 5G networks.

[0005] Background of the Invention

[0006] Modern cellular communication systems such as 5G New Radio (NR), 5G Advanced, and future 6G networks employ large-scale antenna arrays and multi-antenna user equipment (UE) to enhance spectral efficiency, improve coverage, and support high-capacity data transmission across diverse deployment scenarios. In such systems, sounding reference signals (SRS) transmitted in the uplink are critical for enabling the base station (gNB) to estimate the uplink channel and, by leveraging time division duplex (TDD) reciprocity, to derive accurate downlink channel state information (DL-CSI). The DL-CSI is subsequently used for link adaptation, beamforming, and scheduling decisions that directly impact overall system performance.

[0007] As the number of antennas and supported transmission points increase, the SRS configuration in NR has become more complex. The introduction of SRS port grouping in 3GPP Release 19 defines a LIE capability that allows SRS ports to be organized into logical groups. This feature is intended to reduce UE receiver complexity and facilitate antenna switching and reciprocity-based DL-CSI acquisition, particularly for low- complexity and power-constrained UEs.

[0008] However, existing 3GPP NR specifications, including TS 38.214, do not provide explicit or standardized mechanisms for mapping SRS ports to different port groups when SRS port grouping is enabled. The current definitions also lack clear guidance on numbering rules and resource associations for UEs configured with higher-order antenna settings such as 2T6R, 2T8R, or4T8R. This ambiguity results in inconsistent implementation across vendors and limits interoperability between UEs and networks.

[0009] Without well-defined RRC-controlled parameters and configuration rules, both network nodes and UEs face challenges in ensuring consistent SRS resource configuration. This leads to inefficiencies in DL-CSI acquisition, potential misalignment in port numbering, and degraded performance in multi-antenna environments. The absence of a network- controllable mechanism to signal and manage SRS port grouping also restricts the ability of operators to dynamically optimize resources based on UE capability and deployment conditions.

[0010] Accordingly, there is a clear technical need for a unified method that enable explicit network-signaled control of SRS port grouping and port numbering. Such a mechanism should allow the base station to configure SRS resources dynamically through an RRC parameter or configuration flag, enabling UEs to apply consistent grouping and ordering across all SRS resources. The present invention addresses this need by introducing a flag- controlled, network-driven SRS configuration framework that ensures accurate and flexible port grouping, thereby supporting efficient DL-CSI estimation and robust operation in advanced multi-antenna systems.

[0011] Objective of the Invention

[0012] The principal objective of the present invention is to provide a universal, network-signaled approach for configuring sounding reference signal (SRS) port grouping that enables flexible and centralized control of SRS resources in wireless communication systems, ensuring accurate and efficient downlink channel state information (DL-CSI) acquisition across user equipment (UE) with different antenna configurations and complexity levels.

[0013] Another objective of the invention is to introduce a flag-based, standards-compliant configuration method in which a single parameter or flag is used to enable or disable SRS port grouping across multiple SRS resources and resource sets, allowing seamless adaptation to current and future NR, 5G Advanced, and 6G systems.

[0014] A further objective of the invention is to provide dynamic control of SRS port-to-port group mapping and unambiguous port numbering through explicit signaling from the base station, enabling UEs of varying complexity to transmit SRSs efficiently without vendor-specific implementation or manual adjustment.

[0015] Another objective of the invention is to ensure scalability and compatibility by extending SRS port grouping to all resource types, including periodic, semi-persistent, and aperiodic configurations, and to antenna configurations such as 2T6R, 2T8R, and 4T8R, using a unified, network- controlled configuration process.

[0016] Another objective of the invention is to reduce implementation complexity and operational overhead, particularly for low-complexity UEs, by standardizing SRS port pairing, grouping, and consecutive numbering through a centrally signaled configuration flag, thereby minimizing UE-side processing and aligning with emerging wireless standards.

[0017] A further objective of the invention is to support interoperability and future standardization by defining methods, apparatuses, and computer- readable programs that enable consistent, RRC-based SRS port grouping across wireless systems, providing reliable operation and improved performance in advanced multi-antenna, TDD-based communication networks.

[0018] Summary of the Invention

[0019] The present invention provides a universal configuration framework for sounding reference signal (SRS) resources in wireless communication systems, enabling precise and dynamic grouping of SRS ports for accurate downlink channel state information (DL-CSI) acquisition. The configuration is centrally controlled by a network node (base station or gNB) through the use of a standards-compliant, flag-based signaling mechanism, allowing the network to activate or deactivate SRS port grouping across multiple UEs and SRS resource types without requiring custom or manual UE-side grouping logic.

[0020] The system comprises an SRS-ResourceSet configured for each user equipment and incorporates a configuration flag implemented as a radio resource control (RRC) parameter that determines whether SRS port grouping is enabled. When the flag is activated, each SRS resource comprising a plurality of SRS ports is mapped to at least two distinct UE SRS port groups in accordance with network-specified port grouping rules. The assignment of consecutive and ascending port numbers within each SRS resource is enforced to standardize resource transmission and facilitate interoperability across diverse UE antenna configurations, including but not limited to 2T6R, 2T8R, and 4T8R systems.

[0021] Upon receiving the grouping configuration, the UE automatically applies the prescribed port-group mapping and numbering when transmitting SRSs, regardless of resource type (periodic, semi-persistent, or aperiodic). The configuration logic supports multiple resource sets, prevents conflicting semi-persistent activations, and ensures that each UE SRS port group is correctly mapped to antenna-port pairs for optimum reciprocity in TDD networks. The invention further features implementations via software instructions stored on a non-transitory computer-readable medium, enabling both base station and UE processors to programmatically configure, map, assign, and transmit SRS resources according to the network-controlled grouping and numbering policy.

[0022] Accordingly, the invention provides a scalable, standards-compliant, and highly efficient method, apparatus, and software framework for SRS resource configuration and port grouping. It enables real-time, dynamic grouping of SRS ports signaled from the network, unifies transmission and resource management across heterogeneous UE types and antenna counts, significantly reduces operational and receiver complexity, and enhances DL-CSI estimation performance for network planning, scheduling, and beamforming in advanced 5G / 6G wireless systems. This invention addresses the limitations of current standards and vendor-specific approaches, delivering reliable, actionable channel state information management for next-generation wireless infrastructures.

[0023] Brief description of the drawings

[0024] The figures described below depict various aspects of the system and methods disclosed herein. It should be understood that each figure depicts an embodiment of a particular aspect of the disclosed system and methods, and that each of the figures is intended to accord with a possible embodiment thereof. Further, wherever possible, the following description refers to the reference numerals included in the following figures, in which features depicted in multiple figures are designated with consistent reference numerals.

[0025] Figure 1 illustrates a conventional system block diagram (100) of a wireless communication network comprising a base station (gNB) and multiple user equipment (UEs), where the assignment of SRS ports to port groups is undefined, according to one embodiment of the present invention.

[0026] Figure 2 illustrates an enhanced system block diagram (200) of a wireless communication network comprising a base station (gNB) and a user equipment (UE), where the assignment of SRS ports to defined port groups is enabled and managed via SRS port grouping modules and RRC configuration signaling, according to one embodiment of the present invention.

[0027] Figure 3 illustrates a flow chart (300) of an example process for enabling SRS port grouping for a user equipment (UE), including configuration, flag setting, parameter transmission, port grouping, and acquisition of downlink channel state information (DL-CSI), according to one embodiment of the present invention.

[0028] Figure 4 illustrates a schematic block diagram (400) of a network (405) comprising network interference detection (410), a processor (415), storage (420), and memory (425), according to one embodiment of the present invention. Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.

[0029] Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

[0030] Detailed Description of the Invention

[0031] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0032] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0033] The terms and words used in the following description and claims are not limited to the bibliographical meanings but are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0034] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a component surface" includes reference to one or more of such surfaces.

[0035] Figures discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way that would limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged system. The terms used to describe various embodiments are exemplary. It should be understood that these are provided to merely aid the understanding of the description, and that their use and definitions, in no way limit the scope of the invention. Terms first, second, and the like are used to differentiate between objects having the same terminology and are in no way intended to represent a chronological order, unless where explicitly stated otherwise. A set is defined as a non-empty set including at least one element.

[0036] Figure 1 illustrates a conventional system block diagram (100) of a wireless communication network, representing a configuration in accordance with existing New Radio (NR) specifications prior to Release 19. The network comprises a base station (gNB) and one or more user equipments (UEs) configured to perform uplink sounding reference signal (SRS) transmission for enabling the gNB to acquire downlink channel-state information (DL-CSI). The UE includes a plurality of antenna ports, denoted as AO through A7, each associated with a corresponding SRS port that transmits an SRS signal toward the gNB.

[0037] In the conventional configuration shown in Figure 1 , the transmission paths between the UE and the gNB indicate that the relationship among the SRS ports is undefined, such that each SRS port functions independently and there is no predetermined or standardized association between the ports for uplink sounding. The gNB receives the SRS signals independently from each port and performs CSI estimation without any awareness of logical groupings among the ports.

[0038] According to Clause 6.2.1.2 of 3GPP TS 38.214, each SRS resource within an SRS-ResourceSet may comprise one or more SRS ports, and the SRS port or SRS-port pair of each resource is merely required to be associated with a different UE-antenna-port pair. However, no rule is defined for grouping, numbering, or ordering of the ports across multiple SRS resources or resource sets. Consequently, different vendors may employ distinct mappings between SRS ports and antenna ports, which leads to inconsistent and non-deterministic behavior during DL-CSI estimation. For example, in a typical 2T8R UE configuration, a conventional implementation may associate the SRS resources and antenna ports as follows: resource #0 - {0, 4}, resource #1 -> {1 , 5}, resource #2 — > {2, 6}, and resource #3 - {3, 7}. Although this mapping satisfies the legacy requirement that each SRS resource employ a different antenna-port pair, it lacks any deterministic structure across resources and does not guarantee consecutive or group-based port numbering. As a result, the same antenna ports may be interpreted differently for uplink sounding and for downlink beam management, depending on vendor-specific implementation choices. The absence of a defined association between SRS ports and port groups introduces several technical limitations. Because the gNB cannot determine which subset of antenna ports corresponds to a received SRS, reciprocity between uplink and downlink channels is weakened, resulting in uncertainty in DL-CSI derivation. For UEs employing antenna-switching architectures particularly low-complexity UEs configured for 2T6R or 2T8R operation the undefined relationship among SRS ports prevents consistent port management, causing mismatched scheduling decisions and sub-optimal beamforming at the gNB. Moreover, consecutive SRS resources may reference unrelated antenna ports, creating discontinuities in the CSI estimation process and degrading coherence across transmission intervals.

[0039] Additionally, the legacy framework does not include any higher-layer parameter that allows the network to indicate whether SRS port grouping should be applied or how SRS ports should be logically arranged. The gNB therefore performs DL-CSI estimation on a per-port basis, while the UE transmits SRS signals without any grouping awareness. This lack of coordination increases implementation complexity and leads to inconsistent performance across multi-vendor systems. In periodic, semi-persistent, and aperiodic SRS configurations, the absence of a defined port-grouping rule further results in irregular port reuse, reduced CSI accuracy, and degraded spectral efficiency.

[0040] Figure 2 illustrates an enhanced system block diagram (200) of a wireless communication system implementing a Sounding Reference Signal (SRS) port grouping mechanism for facilitating downlink channel state information (DL-CSI) acquisition according to one or more embodiments of the present invention. The system includes a base station, also referred to as a gNodeB (gNB), and a user equipment (UE), wherein the configuration, activation, and utilization of SRS port groups are enabled and managed through higher-layer signaling and port grouping control.

[0041] In the illustrated embodiment, the gNB comprises an RRC Configuration module, a Port Grouping Controller, and a Downlink Channel State Information (DL-CSI) Processor. The RRC Configuration module is responsible for generating and transmitting configuration information defining SRS resources and resource sets, including a new higher-layer parameter denoted as srsPortGrouping-r19. The parameter srsPortGrouping-r19 is included within the SRS-ResourceSet Information Element (IE) and is defined to indicate whether SRS port grouping is enabled for the corresponding SRS configuration. The parameter is applicable when the codebook configuration (codebookConfig) in the CSI- ReportConfig is set to CSI-Type-l or CSI-Type-ll, and when the reporting quantity (reportQuantity) for CSI feedback is configured as cri-RI-CQI. In some embodiments, the parameter is applicable particularly for UEs configured with antenna switching (AS) modes for xT6R or xT8R antenna configurations, where “xT” indicates the number of transmit ports and “R" the number of receive ports.

[0042] In some embodiments, a user equipment (UE) supporting the SRS port grouping feature is configured with the following aspects. The configuration comprises a new higher-layer parameter defined as srs- PortGrouping-r19, which is indicated as enabled by a base station (gNB) to inform the UE that SRS port grouping is active. The configuration further includes one or more SRS resource sets having the higher-layer parameter usage set to “antennaSwitching,” with a total of four, six, or eight ports across the resources intended respectively for xT4R, xT6R, or xT8R antenna configurations. The higher-layer parameter reportQuantity in the CSI-ReportConfig, for which the CQI is reported, is set to cri-RI-CQI.

[0043] In some embodiments realizing the SRS port grouping feature, an association between SRS port groups and downlink codewords (CWs) is defined. In one configuration, if a single codeword is scheduled, both SRS port groups may be mapped to the same codeword; in a multi-codeword scenario, such as when two CWs are scheduled, each SRS port group is associated with a distinct CW to enable coherent or non-coherent transmission. This mapping behavior is particularly relevant for low- complexity UEs equipped with four, six, or eight receive (Rx) antennas, where SRS port grouping supports CSI codebook Type-1 and Type-ll reporting structures. Different SRS ports are explicitly linked to distinct UE antenna ports to prevent overlap between groups.

[0044] According to some embodiments, realizing flexible SRS port grouping further requires providing explicit UE assumptions for CQI calculation and defining a port grouping mechanism in which SRS ports are grouped based on the SRS resource set identifier, resource identifier within the set, and port number within each resource. Such a configuration allows both explicit and implicit association of SRS port groups to distinct UE antenna ports, ensuring deterministic mapping and consistent interpretation across UE and gNB implementations.

[0045] The srsPortGrouping-r19 parameter may be signaled as a one-bit enable / disable flag or as an enumerated parameter value. When enumerated, the parameter may take a value {enabled}, indicating that the SRS port grouping feature is active for the corresponding UE. Upon reception of the RRC configuration message containing the srsPortGrouping-r19 = enabled setting, the UE activates its SRS Port Grouping Module to implement the grouping logic.

[0046] The Port Grouping Controller at the gNB ensures that this configuration is consistent with the gNB’s DL transmission structure and CSI measurement framework. The gNB’s DL CSI Processor utilizes the uplink SRS signals received from the grouped SRS ports to perform channel estimation, determine beamforming vectors, and derive downlink channel quality metrics such as CQI (Channel Quality Indicator) and Rl (Rank Indication). These operations support efficient downlink scheduling and beam selection based on reciprocity principles.

[0047] At the UE side, the Antenna Array comprises multiple antenna ports, shown as A0-A7 in Figure 2, which are mapped to specific SRS ports. The SRS Port Grouping Module associates the SRS ports into two predefined port groups, Group 1 (even-numbered ports: AO, A2, A4, A6) and Group 2 (odd-numbered ports: A1 , A3, A5, A7). The mapping ensures that each group contains one half of the total configured SRS ports (PSRS / 2). This association provides a fixed and deterministic mapping that can be consistently interpreted by both UE and gNB implementations. The UE assumes that SRS Port Group #1 corresponds to codeword 0 and SRS Port Group #2 corresponds to codeword 1 for downlink data transmission.

[0048] In one embodiment, the SRS ports are indexed in an ascending order according to SRS resource ID and port number within each SRS resource. In the case of multiple aperiodic SRS resource sets, the indexing is based on SRS resource set ID, SRS resource ID within the set, and port number within each SRS resource. This indexing mechanism ensures that the mapping between antenna ports and port groups remains sequential and standardized, thereby eliminating implementation ambiguities. The SRS Port Grouping Module within the UE thereby applies the configuration to associate even-numbered PSRS / 2 ports with Group 1 and odd-numbered PSRS / 2 ports with Group 2, as shown in the figure. Each port within a group is uniquely associated with a UE antenna port, ensuring one- to-one correspondence between SRS ports and antenna ports. This explicit definition ensures that, for each SRS resource, the two ports constituting an SRS port pair belong to different SRS port groups, thereby maintaining orthogonality during simultaneous SRS transmissions.

[0049] In one example scenario, where the UE is configured for 2T8R, the legacy 3GPP NR specification (TS 38.214, Clause 6.2.1.2) defines that each SRS resource in a given set consists of two SRS ports, and that the SRS port pair of the resource is associated with a different UE antenna port pair. Under such legacy behavior, one possible interpretation is that the SRS port pairs across resources may map to antenna pairs (0,4), (1 ,5), (2,6), and (3,7). However, this interpretation leads to inconsistencies when SRS port grouping is enabled. According to the embodiments disclosed herein, the mapping is redefined such that SRS port pairs are associated with consecutive antenna port pairs for example, (0,1), (2,3), (4,5), and (6,7) ensuring that each SRS port within a pair belongs to a distinct SRS port group and preserving consecutive port numbering.

[0050] In some embodiments, interpretation of mapping in UE sounding procedure for DL CSI acquisition is possible only if x / 2 UE antenna ports among the x different UE antenna ports are associated with a different UE SRS port group than the SRS port group of the other x / 2 antenna ports and the x different antenna ports follow consecutive port numbering if the UE is configured with SRS port grouping. An alternative way to achieve the above requirement is by defining that the SRS ports are indexed in an ascending order according to SRS resource ID and port number within each SRS resource, for one SRS resource set, or according to SRS resource set ID, SRS resource ID in a set and port number within each SRS resource, for multiple aperiodic SRS resource sets.

[0051] In some embodiments, the Clause 6.2.1.2 in TS38.214 for UE sounding procedure for DL CSI acquisition may be modified when enabling the SRS port grouping feature. The disclosed changes ensure enhanced clarity and alignment with the intended behavior of SRS port grouping in Rel-19.

[0052] It may be noted that the disclosed enhancements in the NR specification eliminates vendor-specific interpretation inconsistencies in UE sounding procedure when implementing SRS port grouping feature for the SRS AS that can arise due to lack of guidance on associating antenna ports across resources and resource sets for the port groups.

[0053] In some embodiments, the predefined directive to the gNB and UE that supports SRS port grouping feature can be generalized as;

[0054] - For xTyR, SRS resource set(s) configured with resourceType in SRS- ResourceSet set to 'aperiodic', with y / x or a total of y / x resources, the x SRS ports of each resource in the set(s) are associated with different UE antenna ports, where x / 2 UE antenna ports among the x different UE antenna ports are associated with a different UE SRS port group than the SRS port group of the other x / 2 antenna ports and the x different antenna ports follow consecutive port numbering if the UE is configured with SRS port grouping.

[0055] In some embodiments, for 2T6R, if the UE is configured with SRS port grouping, then each UE antenna port in a UE antenna port pair is associated with a different UE SRS port group than the SRS port group of the other antenna port, and the UE antenna port pair follow consecutive port numbering if the UE is configured with SRS port grouping.

[0056] In some other embodiments, for 2T8R, if the UE is configured with SRS port grouping, then each UE antenna port in a UE antenna port pair is associated with a different UE SRS port group than the SRS port group of the other antenna port, and the UE antenna port pair follow consecutive port numbering if the UE is configured with SRS port grouping.

[0057] In some further embodiments, for 4T8R, if the UE is configured with SRS port grouping, then the two UE antenna ports among the four different UE antenna ports are associated with a different UE SRS port group than the SRS port group of the other two antenna ports, and the four different UE antenna ports follow consecutive port numbering.

[0058] The explicit redefinition of this mapping behavior, enabled through the srsPortGrouping-r19 parameter and its associated signaling, ensures deterministic operation across gNB and UE vendors. It eliminates vendor- specific interpretation inconsistencies, enhances coverage and reciprocity alignment, and supports efficient DL CSI acquisition for both Type-1 and Type-11 codebooks.

[0059] Figure 3 illustrates a flowchart (300) depicting an example process for configuring and enabling Sounding Reference Signal (SRS) port grouping in a wireless communication system, according to one or more embodiments of the present invention. The process represents cooperative operations between a base station (gNodeB or gNB) and a user equipment (UE) for defining, signaling, and applying SRS port grouping to facilitate downlink channel state information (DL-CSI) acquisition. The disclosed method introduces a higher-layer configuration parameter for enabling port grouping, defines deterministic mapping between SRS ports and UE antenna ports, and standardizes the association of port groups to codeword identifiers to improve reciprocity-based channel estimation.

[0060] At step 305, the gNB prepares configuration information for at least one SRS-ResourceSet for the UE. The configuration is defined through higher-layer signaling and includes a usage parameter set to antennaSwitching, enabling the UE to transmit uplink SRS signals that are used for reciprocity-based downlink channel estimation. The configuration supports antenna arrangements such as xT4R, xT6R, and xT8R. The configuration is associated with a CSI-ReportConfig in which the reportQuantity parameter is set to cri-RI-CQI, thereby ensuring that the CQI (Channel Quality Indicator) and Rl (Rank Indicator) values are derived from SRS-based measurements corresponding to the configured antenna ports and SRS ports. When such a configuration is provided, the UE prepares to perform SRS-based sounding for DL-CSI acquisition under antennaswitching conditions.

[0061] At step 310, the gNB defines a higher-layer configuration parameter identified as srs-PortGrouping-r19, which is included within the SRS- ResourceSet Information Element (IE) of a radio resource control (RRC) configuration message. The parameter indicates whether the SRS port grouping feature is enabled for the corresponding UE. The parameter may be signaled either as a one-bit flag, wherein a first value indicates that SRS port grouping is enabled and a second value indicates that it is disabled, or as an enumerated parameter value such as {enabled}. When enumerated, the parameter being present in the RRC message itself serves as the enablement indication. The parameter is applicable when the codebookConfig field in CSI-ReportConfig corresponds to CSI-Type-l or CSI-Type-ll codebook reporting, and when the SRS configuration is associated with antenna-switching operation for xT6R or xT8R UEs. The gNB includes the srs-PortGrouping-r19 field within the SRS-ResourceSet IE of the RRC configuration and transmits the message to the UE. The inclusion and enablement of this parameter explicitly instruct the UE to activate the SRS port grouping behavior.

[0062] At step 315, once the SRS port grouping enablement is defined, the gNB establishes the port grouping parameters and corresponding numbering rules. These include the total number of configured SRS ports (PSRS), the number of defined SRS port groups, and the association of each port group with a subset of UE antenna ports. The SRS ports are indexed in ascending order according to the SRS Resource ID and the port number within each SRS resource. In cases where multiple aperiodic SRS resource sets are configured, the indexing is performed sequentially according to the SRS ResourceSet ID, the SRS Resource ID within the set, and the port number within each resource. For antenna-based association, the gNB defines explicit mapping rules ensuring that each SRS port within a pair is linked to a different UE antenna port, and that each SRS port pair corresponds to consecutive antenna-port numbering. This provides deterministic indexing and avoids any ambiguity in the association between antenna ports and SRS ports across implementations.

[0063] At step 320, the gNB transmits the RRC configuration message containing the SRS-ResourceSet IE and the srs-PortGrouping-r19 parameter to the UE. The message includes the mapping rules, grouping parameters, numbering scheme, and association between SRS ports and antenna ports. This message represents the explicit signaling of configuration information that enables the UE to apply the port grouping function.

[0064] At step 325, upon receiving the RRC configuration message, the UE decodes it, extracts the srs-PortGrouping-r19 parameter, and determines whether the SRS port grouping feature is enabled. If the parameter indicates disablement, the UE continues operating in a legacy mode; if the parameter indicates enablement, the UE proceeds to activate the grouping procedure.

[0065] At step 330, when the srs-PortGrouping-r19 parameter indicates enablement, the UE activates its internal SRS Port Grouping Module. This module applies the port grouping logic, manages association of SRS ports to port groups, and ensures alignment with antenna-port mapping rules defined in the configuration received from the gNB.

[0066] At step 335, the UE performs grouping and numbering of SRS ports and corresponding antenna ports in accordance with the received configuration. In one exemplary embodiment, the UE divides the configured SRS ports into two SRS port groups, where even-numbered SRS ports (0, 2, 4, 6) are assigned to Group 1 , and odd-numbered SRS ports (1 , 3, 5, 7) are assigned to Group 2. Each port group corresponds to a distinct subset of UE antenna ports having consecutive numbering, such as (0, 1), (2, 3), (4, 5), and (6, 7). The UE assumes a definitive association such that SRS Port Group #1 corresponds to codeword 0, and SRS Port Group #2 corresponds to codeword 1. This association is used by the UE for deriving CQI and Rl values applicable for downlink data transmission. The fixed mapping of port groups to codewords ensures consistent behavior between the UE and gNB during channel reporting and DL scheduling. The grouping may also support configurations with four, six, or eight total SRS ports corresponding respectively to xT4R, xT6R, orxT8R antenna arrangements. In certain implementations, the number of port groups may be extended beyond two, as determined by network configuration.

[0067] At step 340, the UE transmits SRS resources according to the configured SRS-ResourceSet and the established port-to-antenna mapping. Each SRS resource may include one or more SRS ports, and the ports within each resource are associated with different SRS port groups and distinct antenna ports to preserve orthogonality during simultaneous transmissions. The gNB receives the SRS signals and derives uplink channel estimates corresponding to each port group and antenna association. These estimates are used to determine appropriate downlink beam selection, precoding, and resource scheduling based on reciprocity principles. The disclosed configuration is applicable across periodic, semi- persistent, and aperiodic SRS resource sets to ensure unified port grouping behavior regardless of transmission periodicity

[0068] At step 345, the gNB, using its Downlink CSI Processor, derives downlink CSI parameters such as CQI, Rl, and precoding matrix indicator (PMI) based on the received SRS signals and the defined port-to-antenna mapping. The resulting CSI parameters are applied to optimize downlink beamforming, power allocation, and resource scheduling for the UE. This configuration enhances reciprocity-based DL CSI accuracy while reducing receiver complexity, particularly for low-complexity UEs configured with multiple receive antennas. In other embodiments, the sequence illustrated in Figure 3 represents a method for configuring and enabling Sounding Reference Signal (SRS) port grouping in a wireless communication system. In such embodiments, configuration information is provided by a network node, such as a base station or gNB, to a user equipment (UE) for one or more SRS resource sets having a usage parameter set to antennaSwitching. The configuration further comprises signaling of a higher-layer parameter, for example, srs-PortGrouping-r19, which indicates whether the SRS port grouping feature is enabled for the corresponding UE configuration. Upon receiving and decoding the configuration, the UE identifies the enablement of SRS port grouping and accordingly divides a plurality of SRS ports into at least two SRS port groups. In one example, even-numbered SRS ports are assigned to a first port group and odd-numbered SRS ports are assigned to a second port group. Each port group is associated with a distinct codeword identifier or transmission entity for use in downlink data transmission or channel state information reporting.

[0069] In some embodiments, the SRS ports may be indexed in ascending order according to SRS resource identifiers and port numbers, or sequentially according to SRS resource set identifiers, SRS resource identifiers within a set, and port numbers within each resource. This ordered indexing facilitates deterministic mapping between SRS ports and UE antenna ports, ensuring consistent correspondence across configurations. Each SRS port group may be mapped to a unique subset of antenna ports having consecutive numbering, thereby maintaining a structured and nonoverlapping association between SRS resources and antenna elements.

[0070] In certain embodiments, the configuration information indicating the enablement of SRS port grouping is signaled as a one-bit flag or as an enumerated parameter value, for instance, a field indicating a value of enabled. The configuration may also support dynamic grouping arrangements wherein more than two port groups are defined based on network or deployment requirements.

[0071] In some other embodiments, the network node utilizes the grouped SRS transmissions from the UE to estimate uplink channel characteristics and derive downlink channel state information (DL-CSI) parameters such as the channel quality indicator (CQI), rank indicator (Rl), and precoding matrix indicator (PMI). The derived parameters are then applied fordownlink beamforming, power allocation, and scheduling decisions.

[0072] Through the use of the described configuration and signaling, these embodiments provide an explicit and standardized framework for SRS based sounding and DL-CSI acquisition. The introduction of the higher-layer signaling parameter and deterministic mapping between SRS ports, antenna ports, and codeword identifiers eliminates ambiguity present in legacy specifications and ensures consistent interpretation between the gNB and UE. This results in improved reciprocity-based CSI estimation accuracy, efficient downlink beam management, and enhanced system performance in multi-antenna configurations, particularly for UEs configured with multiple receive antennas in next-generation wireless systems such as 5G NR Release 19 and beyond.

[0073] Figure 4 illustrates a block diagram (400) of an example architecture for implementing Sounding Reference Signal (SRS) port grouping in a wireless communication system, according to one or more embodiments of the present invention. The illustrated embodiment represents a network entity (405), which may correspond to a user equipment (UE), a base station (gNodeB or gNB), or another wireless node configured to perform SRS configuration, grouping, and channel state information (CSI) processing operations.

[0074] As shown, the network (405) includes a network interface (410), a processor (415), a storage unit (420), and a memory (425), which are operatively coupled to exchange control and data information. The network interface (410) facilitates communication with other network elements and, in the context of the UE, functions as a transceiver configured to receive configuration information for one or more SRS resource sets transmitted by the base station. The configuration information includes a higher-layer parameter, such as srs-PortGrouping-r19, indicating whether SRS port grouping is enabled. The interface may also transmit signaling indicative of the association between grouped SRS ports and codewords for use in downlink transmission and CSI reporting.

[0075] The processor (415) executes stored instructions to control SRS port grouping operations. Upon reception of configuration information, the processor determines whether SRS port grouping is enabled and, when enabled, groups a plurality of SRS ports into distinct port groups. In one embodiment, even-numbered SRS ports are assigned to a first port group and odd-numbered ports are assigned to a second port group. Each port group is associated with a corresponding codeword identifier, enabling codeword-based downlink transmission. The processor may further index SRS ports in ascending order according to SRS resource and port identifiers, ensuring deterministic mapping across configurations. The processor may also support grouping configurations for four, six, or eight total SRS ports corresponding to xT4R, xT6R, or xT8R antenna configurations, and may map each port group to a unique subset of UE antenna ports having consecutive numbering.

[0076] In certain embodiments, the processor implements hierarchical, nested, or adaptive grouping logic, dynamically modifying port grouping based on real-time network feedback or channel conditions. The processor may also support CSI codebook Type-1 or Type-11 reporting schemes for port group mapping. The storage (420) and memory (425) store configuration data, lookup tables, and executable instructions that, when executed by the processor, cause performance of operations such as grouping of SRS ports, determining port-to-antenna mapping, and transmitting signaling information.

[0077] In some embodiments, the components of Figure 4 represent a user equipment (UE) comprising a transceiver (410) and a processor (415) configured to receive configuration information for at least one SRS resource set, determine SRS port grouping enablement, group the ports into even-numbered and odd-numbered groups, associate each group with a codeword identifier, and transmit signaling indicative of the association to the base station. In other embodiments, Figure 4 represents a base station (gNB) configured to transmit SRS port grouping configuration to the UE, where the grouping parameter is defined as srs-PortGrouping-r19, applicable when antenna switching and reportQuantity = cri-RI-CQI are present. The base station and UE may dynamically or statically assign codeword mappings for downlink transmission based on grouped SRS ports, with mapping defined explicitly or implicitly to avoid vendor-specific interpretation inconsistencies.

[0078] In yet another embodiment, the architecture of Figure 4 may be implemented through a non-transitory computer-readable medium storing instructions that, when executed by one or more processors of the base station or UE, cause operations including transmitting configuration information for one or more SRS resource sets, determining enablement of SRS port grouping, grouping SRS ports into two or more groups, associating each port group with a codeword identifier, and transmitting the corresponding signaling to the network node. The instructions may further cause dynamic or adaptive division of SRS ports into multiple groups based on network feedback or operational requirements. A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.

Claims

We Claim:

1. A method for configuring sounding reference signal (SRS) port grouping in a wireless communication system, the method comprising: transmitting, by a base station, configuration information to a user equipment (UE) for at least one SRS resource set having usage set to antenna switching, the configuration information including a parameter indicating whether SRS port grouping is enabled; grouping, by the UE, upon enabling SRS port grouping, a plurality of SRS ports into two SRS port groups, wherein the grouping comprises assigning even-numbered SRS ports to a first SRS port group and odd- numbered SRS ports to a second SRS port group; and associating each SRS port group with a corresponding codeword identifier and transmitting signaling indicative of the association to the base station for use in downlink data transmission.

2. The method as claimed in claim 1 , wherein transmitting signaling indicative of the association to the base station comprises the UE assuming the definite association for the purpose of deriving channel quality indicator (CQI) index and rank indicator (Rl) for use in downlink data transmission.

3. The method as claimed in claim 1 , wherein the parameter is defined as srs-PortGrouping-r19.

4. The method as claimed in claim 1 , wherein the configuration information supports grouping of four, six, or eight SRS ports corresponding respectively to antenna configurations of xT4R, xT6R, or xT8R.

5. The method as claimed in claim 1 , wherein SRS port grouping is enabled when an associated reportQuantity parameter in CSI-ReportConfig is set to cri-RI-CQI.

6. The method as claimed in claim 1 , further comprising indexing the SRS ports in ascending order according to SRS resource identifier and port number for one SRS resource set, or sequentially according to SRS resource set identifier, SRS resource identifier in the set, and port number for multiple SRS resource sets.

7. The method as claimed in claim 1 , further comprising mapping each SRS port group to a unique subset of UE antenna ports with consecutive numbering, wherein the mapping is based on an association predefined by the network, the UE, or both.

8. The method as claimed in claim 1 , wherein transmitting the configuration information as a higher layer parameter comprises signaling a one-bit flag, the one-bit flag being set to a first value to indicate to the user equipment that SRS port grouping is enabled, and set to a second value to indicate to the user equipment that SRS port grouping is disabled.

9. The method as claimed in claim 1 , wherein the configuration information further comprises signaling an enumerated parameter, the enumerated parameter being signaled only when SRS port grouping is enabled, to indicate to the user equipment that SRS port grouping is enabled.

10. The method as claimed in claim 1 , further comprising transmitting the parameter as configuration information, by a base station, to the user equipment as a higher layer parameter included in an SRS-ResourceSet information element (IE) within a radio resource control (RRC) configuration message.

11. The method as claimed in claim 1 , further comprising reducing receiver complexity and improving channel reciprocity-based downlink channel state information (DL-CSI) estimation for low-complexity UEs by enabling SRS port grouping.

12. The method as claimed in claim 1 , wherein grouping of the SRS ports comprises dividing the ports into more than two port groups as specified by dynamic network configuration.

13. A user equipment (UE) configured for sounding reference signal (SRS) port grouping in a wireless communication system, the UE comprising:a transceiver configured to receive configuration information for at least one SRS resource set including a parameter indicating whether SRS port grouping is enabled; and a processor configured to: determine enablement of SRS port grouping from the received configuration information; group a plurality of SRS ports into even-numbered and odd- numbered SRS port groups; and associate each SRS port group with a corresponding codeword identifier and transmit signaling indicative of the association to a base station for use in downlink data transmission.

14. The UE as claimed in claim 13, wherein the SRS ports are indexed in ascending order according to configuration parameters.

15. The UE as claimed in claim 13, wherein the total of four, six, or eight SRS ports are grouped for xT4R, xT6R, or xT8R antenna configurations, respectively.

16. The user equipment (UE) as claimed in claim 13, wherein the processor is configured to receive configuration information comprising a higher layer parameter indicative of an enablement state of sounding reference signal (SRS) port grouping, the higher layer parameter being signaled as one of:a one-bit flag, wherein a first value of the flag indicates to the LIE that SRS port grouping is enabled and a second value of the flag indicates to the UE that SRS port grouping is disabled; or an enumerated parameter, the enumerated parameter being signaled only when SRS port grouping is enabled, to thereby indicate to the UE that SRS port grouping is enabled.

17. The UE as claimed in claim 13, wherein the processor is further configured to map each port group to a unique UE antenna port subset with consecutive numbering.

18. The UE as claimed in claim 13, wherein the processor is further configured to implement hierarchical or nested grouping logic and adapt the grouping dynamically based on network feedback.

19. The UE as claimed in claim 13, wherein the configuration enables channel state information (CSI) codebook Type I or Type II reporting for port group mapping.

20. A wireless communication system comprising: a base station configured to transmit sounding reference signal (SRS) port grouping configuration including a grouping parameter and grouping information; anda user equipment configured to receive, process, and apply the SRS port grouping configuration for codeword association and channel state information (CSI) reporting.21 . The system as claimed in claim 20, wherein the grouping parameter is defined as srs-PortGrouping-r19 and is applicable when antenna switching and a reporting quantity cri-RI-CQI are present.

22. The system as claimed in claim 20, wherein the base station is configured to transmit a higher layer parameter signaled as: a one-bit flag, the one-bit flag being set to a first value to indicate to the UE that SRS port grouping is enabled, and set to a second value to indicate to the UE that SRS port grouping is disabled; or an enumerated parameter, the enumerated parameter being signaled only when SRS port grouping is enabled, to indicate to the UE that SRS port grouping is enabled.

23. The system as claimed in claim 20, wherein the base station and the user equipment are configured to dynamically or statically assign codeword mapping for downlink transmission based on grouped SRS ports.

24. The system as claimed in claim 20, wherein mapping of the SRS port groups to antenna ports comprises both explicit and implicit mapping so as to avoid vendor-specific interpretation inconsistencies.

25. The system as claimed in claim 20, wherein the codeword and antenna mappings are adaptable to support future or proprietary communication standards.

26. The system as claimed in claim 20, wherein the base station and the user equipment are further configured for multi-resource and aperiodic SRS resource sets and flexible grouping configurations.

27. A non-transitory computer-readable medium storing instructions that, when executed by one or more processors of a base station or a user equipment (UE) in a wireless communication system, cause the one or more processors to perform operations comprising: transmitting, by the base station, configuration information for at least one sounding reference signal (SRS) resource set to the UE, the configuration information including a parameter indicating whether SRS port grouping is enabled; grouping, by the UE, upon determining that SRS port grouping is enabled, a plurality of SRS ports into two or more SRS port groups according to the configuration information; and associating each SRS port group with a distinct codeword identifier and transmitting signaling indicative of the association to the base station for use in downlink data transmission.

28. The computer-readable medium as claimed in claim 27, wherein the instructions further cause the one or more processors to enable dynamicdivision of the SRS ports into more than two SRS port groups based on network configuration parameters.

29. The computer-readable medium as claimed in claim 27, wherein the instructions further cause the one or more processors to implement hierarchical, nested, or adaptive grouping of SRS ports based on real-time network feedback.

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