Method and apparatus for allocating sounding reference signal resources in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. A method for handling SRS resource allocation in a multi-TRP in a wireless network by a BS or TRP unit is provided. The method includes configuring a CS allocation to at least one port of the UE. The CS allocation uses values from a subset of the plurality of allowable CS values. In addition, the method includes receiving the SRS using the allocated CS. In embodiments, per port CS allocation provides flexibility to efficiently use CS resources to minimize inter-TRP interference. The method may be used to efficiently allocate CS and SRS resources.

Description

Technical Field

[0001] The present disclosure relates generally to wireless networks, and more particularly, to a method for handling sounding reference signal (SRS) resource allocation in multiple transmit / receive points (TRPs) in a wireless network. Background Art

[0002] 5G mobile communication technology defines a wide frequency band, making high transmission rates and new services possible, and can be realized not only in "below 6 GHz" frequency bands such as 3.5 GHz, but also in "above 6 GHz" frequency bands called mmWave including 28 GHz and 39 GHz. In addition, 6G mobile communication technology (called super 5G system) has been considered to be implemented in terahertz (THz) frequency bands (e.g., 95 GHz to 3 THz frequency bands) to achieve a transmission rate 50 times faster than 5G mobile communication technology and an ultra-low latency of one-tenth of 5G mobile communication technology.

[0003] In the early stages of 5G mobile communication technology development, in order to support services and meet performance requirements associated with enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), and massive machine type communications (mMTC), standardization has been underway on beamforming and massive MIMO for mitigating radio wave path loss and increasing radio wave transmission distance in mmWave, support for dynamic operation of parameter sets (e.g., operating multiple subcarrier spacings) and slot formats for efficient utilization of mmWave resources, initial access technology for supporting multi-beam transmission and broadband, definition and operation of bandwidth parts (BWPs), new channel coding and decoding methods (such as low-density parity-check (LDPC) codes for large amounts of data transmission and polar codes for highly reliable control information transmission), L2 preprocessing, and standardization of network slicing for providing dedicated networks dedicated to specific services.

[0004] Currently, discussions are underway on improvements and performance enhancements of initial 5G mobile communication technologies in consideration of the services that 5G mobile communication technologies will support, and there is already physical layer standardization on technologies such as Vehicle-to-Everything (V2X) for assisting driving determination of autonomous vehicles based on information about the location and status of vehicles transmitted by vehicles and for enhancing user convenience, NR-U (New Radio Unlicensed) designed for system operation to comply with various regulatory-related requirements in unlicensed frequency bands, NR UE power saving, Non-Terrestrial Network (NTN) which is UE-satellite direct communication for providing coverage in areas where communication with terrestrial networks is unavailable, and positioning.

[0005] In addition, standardization is being conducted in air interface architecture / protocols on technologies such as Industrial Internet of Things (IIoT) for supporting new services through interworking and convergence with other industries, Integrated Access and Backhaul (IAB) for providing nodes for network service area expansion by supporting wireless backhaul links and access links in an integrated manner, mobility enhancement including conditional handover and dual active protocol stack (DAPS) handover, and two-step random access (2-step RACH for NR) for simplifying the random access procedure. Standardization is also being conducted in system architecture / services on 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining network function virtualization (NFV) and software defined network (SDN) technologies, and mobile edge computing (MEC) for receiving services based on UE location.

[0006] As 5G mobile communication systems are commercialized, an exponentially increasing number of connected devices will be connected to the communication network, and therefore, it is expected that enhanced functions and performance of 5G mobile communication systems and integrated operations of connected devices will be necessary. To this end, new research is planned in relation to efficient support of extended reality (XR) such as augmented reality (AR), virtual reality (VR), mixed reality (MR), etc., 5G performance improvement and complexity reduction by utilizing artificial intelligence (AI) and machine learning (ML), AI service support, metaverse service support, and drone communication.

[0007] Furthermore, such development of 5G mobile communication systems will serve as a foundation for developing not only new waveforms for providing coverage in the terahertz band for 6G mobile communication technology, multi-antenna transmission technologies (such as full-dimensional MIMO (FD-MIMO), array antennas, and large antennas), metamaterial-based lenses and antennas for improving coverage of terahertz band signals, high-dimensional spatial multiplexing technologies using orbital angular momentum (OAM), and reconfigurable smart surfaces (RIS), but also full-duplex technologies for improving frequency efficiency of 6G mobile communication technology and improving system networks, AI-based communication technologies for achieving system optimization by utilizing satellites and artificial intelligence (AI) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technologies for achieving services of a complexity level that exceeds the limits of UE operating capabilities by utilizing ultra-high performance communication and computing resources. Summary of the invention

[0008] Solution to the problem

[0009] The present disclosure relates to a wireless communication network, and more particularly, to a terminal and a communication method thereof in a wireless communication system.

[0010] According to one aspect of the present disclosure, a method performed by a BS in a wireless network includes: sending configuration information of resource allocation to at least one port of the UE to a UE; and receiving an SRS from the UE based on the configuration information of the resource allocation. The resource allocation includes at least one of a CS allocation or a comb shift allocation, and the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

[0011] Advantageous Effects of the Invention

[0012] Aspects of the present disclosure address at least the above-mentioned problems and / or disadvantages and provide at least the advantages described below.Accordingly, one aspect of the present disclosure is to provide an efficient communication method in a wireless communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent through the following description in conjunction with the accompanying drawings, in which:

[0014] Figure 1 It is shown that SRS is transmitted on every Nth subcarrier;

[0015] Figure 2 It is shown that SRS is transmitted on every Nth subcarrier;

[0016] Figure 3 It is shown that the SRS is transmitted once per transmission comb (kTC) subcarriers in the frequency domain;

[0017] Figure 4 A 2-TRP scenario is shown in which TRP1 and TRP2 are synchronized with each other;

[0018] Figure 5 A scenario is shown in which a Fast Fourier Transform (FFT) of a transmit (Tx), a channel, and a receive (Rx) is depicted;

[0019] Figure 6 is a diagram showing the FFT of a channel at an SRS resource element (RE) due to timing offset / propagation delay;

[0020] Figure 7 is a diagram showing the FFT of the channel at the SRS RE due to timing offset / propagation delay;

[0021] Figure 8 is a diagram showing the FFT of the channel at the SRS RE due to timing offset / propagation delay;

[0022] Fig. 9is a diagram showing the FFT of the channel at the SRS RE due to timing offset / propagation delay;

[0023] Fig.10 is a diagram showing the FFT of the channel at the SRS RE due to timing offset / propagation delay;

[0024] Fig.11 is a diagram showing the FFT of the channel at the SRS RE due to timing offset / propagation delay;

[0025] Fig.12 is a diagram showing the FFT of the channel at the SRS RE;

[0026] Fig.13 is a diagram showing the FFT of the channel at the SRS RE;

[0027] Fig.14 is a diagram showing the FFT of the channel at the SRS RE;

[0028] Fig.15 is a diagram showing the FFT of the channel at the SRS RE;

[0029] Fig.16 shows the CS allocation according to existing standards;

[0030] Fig.17 A wireless network for managing SRS CS resource allocation according to an embodiment is shown;

[0031] Fig.18 shows a BS (or TRP unit) according to an embodiment;

[0032] Fig.19 is a flow chart illustrating a method for managing SRS CS resource allocation in a wireless network according to an embodiment;

[0033] Fig. 20 is a flow chart illustrating a method for channel estimation in a wireless network according to an embodiment;

[0034] Fig.21 is a flow chart illustrating a method for channel estimation in a wireless network according to an embodiment;

[0035] Fig. 22 A method of CS allocation according to an embodiment is shown;

[0036] Fig.23 A method of CS allocation according to an embodiment is shown;

[0037] Fig.24 is a diagram illustrating capacity improvement according to an embodiment;

[0038] Fig.25 shows the allocation of CS to UE according to an embodiment;

[0039] Fig.26 shows the allocation of CS to UE according to an embodiment;

[0040] Fig. 27 is a diagram illustrating the Gibbs phenomenon;

[0041] Fig.28 is a diagram illustrating a comparison of metrics according to an embodiment;

[0042] Fig.29 is a diagram illustrating a comparison of metrics according to an embodiment;

[0043] Fig.30 is a diagram illustrating a comparison of metrics according to an embodiment;

[0044] Fig.31 is a diagram showing performance comparison according to an embodiment;

[0045] Fig.32 is a diagram showing performance comparison according to an embodiment;

[0046] Fig.33 shows allowable CS divided into two subsets and CS values ​​associated with ports hopping within the subsets across orthogonal frequency division multiplexing (OFDM) symbols according to an embodiment;

[0047] Fig.34 shows the allowable CS divided into two subsets and the CS values ​​associated with the ports hopping and muting within the subsets across OFDM symbols according to an embodiment;

[0048] Fig.35 is a diagram showing a performance comparison between CS resource allocation according to an embodiment and a conventional CS resource allocation method;

[0049] Fig.36 is a diagram showing a performance comparison between CS resource allocation according to an embodiment and a conventional CS resource allocation method;

[0050] Fig.37 is a diagram showing a performance comparison between CS resource allocation according to an embodiment and a conventional CS resource allocation method;

[0051] Fig.38 A method of forming a subset from a set of allowable CS values ​​according to an embodiment is shown;

[0052] Fig.39 is a diagram illustrating a Slepian sequence-time half-bandwidth product according to an embodiment;

[0053] Fig.40 is a diagram illustrating a Slepian sequence-time half-bandwidth product according to an embodiment;

[0054] Fig.41 is a diagram showing R according to the embodiment F and R S 's picture;

[0055] Fig.42 is a diagram showing R according to the embodiment F and R S 's picture;

[0056] Fig.43 shows a 2-dimensional (2D) pilot according to an embodiment;

[0057] Fig.44 shows a BS according to an embodiment; and

[0058] Fig.45 A UE according to an embodiment is shown. DETAILED DESCRIPTION

[0059] Aspects of the present disclosure are to address at least the above-mentioned problems and / or disadvantages and provide at least the advantages described below. Therefore, one aspect of the present disclosure is to provide a terminal in a wireless communication system and a communication method thereof.

[0060] The present disclosure has been made to address the above-mentioned problems and disadvantages, and to provide at least the advantages described below.

[0061] Accordingly, an aspect of the present disclosure is to provide a method and apparatus for managing SRS Cyclic Shift (CS) resource allocation in a wireless network.

[0062] Another aspect of the present disclosure is to provide a method for processing SRS resource allocation in multiple TRPs in a wireless network.

[0063] Another aspect of the present disclosure is to provide a method for resource allocation, such as allocating CS, comb size, maximum CS and other SRS resources in a wireless network, which is configurable on a per-port basis via a radio resource control (RRC) message.

[0064] Another aspect of the present disclosure is to provide a receiver for processing multiple TRPs in a wireless network and SRS resource allocation in a single TRP in a wireless network.

[0065] Another aspect of the present disclosure is to provide an improved Orthogonal Time Frequency Space (OTFS) transmitter and receiver for use in a wireless network.

[0066] According to one aspect of the present disclosure, a method performed by a BS in a wireless network includes: sending configuration information of resource allocation to at least one port of the UE to a UE; and receiving an SRS based on the configuration information of the resource allocation from the UE. The resource allocation includes at least one of a CS allocation or a comb shift allocation, and the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

[0067] According to another aspect of the present disclosure, a method performed by a UE in a wireless network includes: receiving configuration information of resource allocation to at least one port of the UE from a BS; and sending an SRS to the BS based on the configuration information of the resource allocation. The resource allocation includes at least one of a CS allocation or a comb shift allocation, and the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

[0068] According to another aspect of the present disclosure, a BS in a wireless communication system includes: a transceiver; and a processor, which is coupled to the transceiver and configured to send configuration information of resource allocation to at least one port of the UE to a UE, and receive an SRS based on the configuration information of the resource allocation from the UE. The resource allocation includes at least one of a cyclic shift (CS) allocation or a comb shift allocation, and the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

[0069] According to another aspect of the present disclosure, a UE in a wireless communication system includes: a transceiver; and a processor, which is coupled to the transceiver and configured to receive configuration information of resource allocation to at least one port of the UE from a BS, and send an SRS to the BS based on the configuration information of the resource allocation. The resource allocation includes at least one of CS allocation or comb shift allocation, and the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

[0070] Mode for use in the present invention

[0071] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in understanding, but these details are considered to be exemplary only. Therefore, it will be appreciated by those of ordinary skill in the art that various changes and modifications may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, for the sake of clarity and conciseness, descriptions of well-known functions and structures may be omitted.

[0072] The terms and words used in the following description and claims are not limited to their bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Therefore, it is clear to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustrative purposes only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0073] Unless the context clearly dictates otherwise, singular forms such as "a," "an," and "the" include plural referents. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0074] Before the following detailed description, it may be helpful to set forth the definitions of certain words and phrases used throughout this patent document.The term "coupling" and its derivatives refer to any direct or indirect communication between two or more elements, whether or not these elements are in physical contact with each other.The terms "send", "receive" and "communication" and their derivatives cover both direct communication and indirect communication.The terms "include" and "comprise" and their derivatives refer to including but not limited to.The term "or" is inclusive, referring to and / or.The phrase "associated with..." and its derivatives refer to including, being included in, being connected to, being interconnected with, being included in, being connected to, being connected to, being coupled to, being coupled to, being coupled to, being able to communicate with, being coordinated with, being intertwined, being juxtaposed, being close to, being bound to, being bound to, having, having the property of, having a relationship to, or having a relationship with, etc.The term "controller" refers to any device, system or part thereof that controls at least one operation.Such a controller can be implemented with hardware or a combination of hardware and software and / or firmware. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely.

[0075] When used with a list of items, the phrase "at least one of" indicates that different combinations of one or more of the listed items may be used, and that only one of the items in the list may be required. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C. For example, "at least one of A, B, or C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C.

[0076] The various functions described below may be implemented or supported by one or more computer programs, each of which is formed of computer-readable program code and contained in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, related data, or a portion thereof suitable for implementation in a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disk (CD), a digital video disk (DVD), or any other type of memory.

[0077] "Non-transitory" computer-readable media do not include wired, wireless, optical, or other communications links that transmit transitory electrical or other signals. Non-transitory computer-readable media include media that can store data permanently and media that can store data and be overwritten later, such as rewritable optical disks or erasable memory devices.

[0078] The terms used herein to describe the embodiments of the present disclosure are not intended to limit and / or define the scope of the present disclosure. For example, unless otherwise defined, the technical terms or scientific terms used in the present disclosure should have the common meanings understood by ordinary technicians in the field to which the present disclosure belongs.

[0079] Ordinal terms such as “first”, “second” and the like used in the present disclosure do not denote any order, quantity or importance, but are merely used to distinguish different components.

[0080] As used herein, any reference to "one example" or "example", "one implementation" or "implementation", "one embodiment" or "embodiment" indicates that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrases "in one embodiment" or "in an example" in various places in the specification are not necessarily referring to the same embodiment.

[0081] As used herein, "a portion" of something means "at least some" of that thing, and thus may mean less than all of that thing or all of that thing. Thus, "a portion" of a thing includes the entire thing as a special case, i.e., the entire thing is an example of a portion of a thing.

[0082] As used herein, the term "set" indicates one or more. Thus, a set of items may be a single item or a cluster of two or more items.

[0083] In the present disclosure, in order to determine whether a specific condition is satisfied or reached, expressions such as "greater than" or "less than" are used as examples, and expressions such as "greater than or equal to" or "less than or equal to" are also applicable and are not excluded. For example, a condition defined with "greater than or equal to" can be replaced with "greater than" (or vice versa), a condition defined with "less than or equal to" can be replaced with "less than" (or vice versa), and the like.

[0084] The term "includes" or "comprising" indicates that the elements or objects preceding the word include the listed elements or objects following the word and their equivalents, but do not exclude other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0085] “Up,” “down,” “left,” and “right” are only used to indicate relative positional relationships, and when the absolute position of the described object changes, the relative positional relationship may change accordingly.

[0086] Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged wireless communication system. For example, although the following detailed description of the embodiments of the present disclosure will be directed to long term evolution (LTE) and / or 5G communication systems, those skilled in the art will appreciate that the gist of the present disclosure can also be applied to other communication systems with similar technical backgrounds and channel formats with slight modifications without departing from the scope of the present disclosure. The technical solutions of the embodiments of the present application can be applied to various communication systems, and for example, the communication system may include a global system for mobile communications (GSM), a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) system, a general packet radio service (GPRS) system, an LTE system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD) system, a universal mobile telecommunications system (UMTS), a global interconnection for microwave access (WiMAX) communication system, a 5G system or an NR system, etc. In addition, the technical solutions of the embodiments of the present application can be applied to future-oriented communication technologies. In addition, the technical solutions of the embodiments of the present application can be applied to future-oriented communication technologies.

[0087] In order to meet the growing demand for wireless data communication services since the deployment of 4G communication systems, efforts have been made to develop improved 5G or quasi-5G communication systems. 5G or quasi-5G communication systems may also be referred to as "super 4G networks" or "post-LTE systems."

[0088] In Release 18 of the 3rd Generation Partnership Project (3GPP), operators of wireless networks are seeking SRS enhancements to manage inter-TRP cross-SRS interference via SRS capacity enhancement and / or interference randomization, targeting TDD coherent joint transmission (CJT), with the following constraints: 1) no additional resources are consumed for SRS, 2) existing SRS comb structure is reused, and 3) no new SRS root sequence.

[0089] In Release 18, operators of wireless networks are also looking to “conduct studies and, if justified, specify the following: Two Timing Advances (TAs) for uplink (UL) multi-DCI for multi-TRP operation”. This means that the TRP knows the propagation delay of the UE to all TRPs. This also means that the user can know the leakage of the effective channel (channel + timing offset to the TRP due to propagation delay). If the UE belongs to the same TRP, the timing offset is zero (its signal arrives at the TRP synchronously), however due to the propagation delay between TRPs, its signal arrives at another TRP with a timing offset. Therefore, even with small cells, where the channel has very weak frequency selectivity, the effective channel due to the propagation delay to another TRP can be more frequency selective. In this case, it may be better to have a configurable CS per port rather than having equidistant CSs on all ports (as per existing approaches). Note that the UE m,n Indicates the nth UE associated with the mth TRP. For simplicity, the number of TRPs = 2.

[0090] Figure 1 and Figure 2 It is shown that SRS is transmitted on every Nth subcarrier.

[0091] refer to Figure 1 and Figure 2 , SRS is transmitted on every Nth subcarrier, where N can take the value 2 or 4 or 8 ("Comb-2" and "Comb-4", respectively). SRS transmissions from different devices can be frequency multiplexed in the same frequency range by being assigned different combs corresponding to different frequency offsets. For Comb-2, i.e., when SRS is transmitted on every second subcarrier, two SRS can be frequency multiplexed. In the case of Comb-4, up to four SRS can be frequency multiplexed.

[0092] Figure 3 It is shown that the SRS is transmitted once every kTC subcarriers in the frequency domain.

[0093] refer to Figure 3 , SRS is sent once per kTC subcarrier in the frequency domain. In each time slot, it has OFDM symbols, and each OFDM symbol has subcarriers in length. It has a configurable period of T time slots, and the SRS has the same value across time slots and OFDM repeats. The value of the nth subcarrier is ,in, is the Zadoff-Chu (ZC) sequence, is the CS for the pth port / user (e.g., UE) (defined in 3GPP standard document 38.211 ), and S is the period of CS (denoted by denoted by ) and can take values ​​of 8, 12 or 6 depending on kTC.

[0094] Figure 4 A 2-TRP scenario is shown in which the first TRP and the second TRP are synchronized.

[0095] refer to Figure 4 ,UE 1,1 The signal of arrives at the first TRP with a timing offset equal to 0 due to TA, and UE 2,1 The signal of arrives at the first TRP with a non-zero timing offset due to propagation delay. 2,1 The signal of arrives at the second TRP with a timing offset equal to 0 due to the TA, and the UE 1,1 The signal arrives at the second TRP with a non-zero timing offset due to propagation delay.

[0096] Figure 5 A scenario is shown where the FFTs of Tx, channel and Rx are depicted.

[0097] refer to Figure 5 , FFT refers to the user performing FFT on the SRS RE (kTC apart). The maximum CS (max CS) is given by c max express. Figure 5 The CS of the Tx signal is c. The channel has an FFT with a shift of S bins and a span of b bins. The effective channel is due to the actual channel, while the exponential rotation is due to the timing offset of the propagation delay. The FFT of the received signal is shifted by S and has a span of b.

[0098] Channel effects due to timing offset (propagation delay)

[0099] If there is a propagation delay or t offset The timing offset of the kth subcarrier channel (for a subcarrier spacing (SCS of 15e3) has f k = k.15e3) will be multiplied by .if , the effect of the timing offset is to shift the FFT of the channel by S intervals.

[0100] Figures 6 to 11 is a diagram showing the FFT of the channel at the SRS RE due to timing offset / propagation delay. Figures 6 to 11 In , the propagation delay corresponds to the distance (dist, in meters (m)).

[0101] Figures 12 to 15 is a diagram showing the FFT of a channel at an SRS RE.

[0102] Fig.16 A method of CS allocation is shown.

[0103] refer to Fig.18 , equidistant allocation of CSs between UEs is not an efficient use of resources. In this document, users may also refer to ports of UEs in the present document, and vice versa.

[0104] Embodiments described herein provide methods for processing SRS resource allocation in multiple TRPs in a wireless network. The method can be used to efficiently allocate CS and SRS resources. For example, a method includes configuring CS allocation to at least one port of a UE by a BS or TRP unit. The CS allocation uses a value from a subset of multiple allowable CS values. In addition, the method includes receiving SRS using the allocated CS by the BS or TRP unit.

[0105] If UEs of other TRPs need to be decoded by a given TRP, further processing should be done. The TRP first estimates the channel of its own UE and then cancels the estimate of the received signal of its own UE from its received signal. This signal can be called the received signal of other UEs (RSOUE). This step can be called the first interference cancellation.

[0106] The TRP then estimates the channels of the UEs from other TRPs using RSOUE. Assume that the timing offsets of the two UEs from other TRPs to the desired TRP are t 1 and t 2 , then when t 1 and t 2 When both are greater than zero, the channels of the two UEs overlap. This method can be used to multiply RSOUE by , where a=t 2 (Assuming t 1 >t 2 ), so that the dispersion of the channels of the UEs of other TRPs seen by the desired TRP is reduced. More importantly, they are now non-overlapping and both channels can be estimated.

[0107] Then multiply the estimated channel by Here, a can be a generic value for channel estimation at the desired / own TRP for any set of UEs from interfering / other TRPs.

[0108] This method can be used to assign all UEs of a TRP in a continuous manner in the CS domain, followed by a gap, followed by all UEs of another TRP, etc., followed by another gap, etc., until all CS are exhausted. The gap of CS is a function of some additional propagation distance for the signal from the UEs of one TRP to the other TRPs. The gap can optionally be zero.

[0109] The CS domain can be divided into multiple areas. Every two areas are separated by a protection band. Areas (TRP1 and TRP2) are allocated to UEs of TRP1 and TRP2 respectively. CS allocation per port configuration can also be performed as follows. The method allocates TRP1 to UEs belonging to TRP1 and TRP2 to UEs belonging to TRP2. This can be done via RRC messages. Within each area, the ports of the UE can be allocated equidistantly. Only signaling notification starts. If necessary, the area wraps around. Alternatively, the method can set the starting position and increment to cover all ports of the UE.

[0110] The method can also be used for resource allocation. The method includes defining all UEs associated with a TRP as a UE group (UEG). A UEG can have multiple resource groups (RGs). Each RG uses the same comb, the same c max .

[0111] Furthermore, the method includes determining a maximum value of a desired bandwidth (BW) for each UE. Furthermore, the method includes determining an interference BW for all UEs.

[0112] The method includes arranging the UEs in the UEG in descending order of their distances to other TRPs. In addition, the method includes assigning all UEs in the UEG (preferring the UE with the largest distance to other TRPs) to a comb such that the difference in CS between two UEs is less than the maximum value of the expected BW of the UEs in the comb. This is done for all UEGs.

[0113] In addition, the method includes using an appropriate comb length or C max. For the remaining UEs in UEG of different TRPs, the method accommodates them in the same comb with appropriate guard bands. Such a comb may be referred to as a mixed-comb. The comb will also have UEs belonging to other TRPs. In a mixed-comb, the guard band may be less than half of the difference between the interfering BW and the desired BW. In this case, the method employs CS hopping and / or comb hopping to reduce interference. CS hopping: The CS of some or all or only edge UEs hops between themselves.

[0114] Comb hopping: Resource groups in a comb or across all combs hop to reduce interference. This method is at a time instant. This method can also be run for various time instances to multiplex multiple UEGs / UEs in time.

[0115] Therefore, the embodiments of this invention also provide a receiver for SRS. In the receiver, the same time-frequency resource is used for N U Here, the channel vector of the ith user is given by vector express, is a basis matrix (Slepian, polynomial, discrete Fourier transform (DFT), oversampled DFT, discrete cosine transform (DCT), Karhunen-Loeve, or any other basis matrix), the subscript M indicates the choice of method, and the basis coefficient vector of the i-th user Depend on Definition ,in, is the concatenation of the basis coefficient vectors of all UEs, which is ,in, is the reference sequence (ZC sequence and CS index) of the i-th user along the diagonal Diagonal matrix.

[0116] In the receiver, the user of the BS has And will Estimated .according to , the proposed method can be used to calculate and estimate as well as .

[0117] The method according to the embodiment provides performance improvement for the receiver and / or capacity improvement in the system.The method can be used to allocate CS, maximum CS, comb size for each SRS port using RRC message, thereby efficiently allocating SRS resources.

[0118] The method shows the advantage of configuring CS and maximum CS for each port. This becomes important because in mTRP, SRS from different TRPs will have different timing advance (TA) (or timing offset) compared to the SRS from own TRP. Users of the network studied this effect in detail and showed how configuring CS for each port can provide advantages. It is proposed in the existing method that if the TA offset between SRS at a TRP is small relative to the cyclic prefix (CP) length, it may not be a big problem, even if all SRS with some arrival timing difference are used for channel estimation.

[0119] This method can be used to configure a subset of comb offsets when comb offset hopping is configured, and to configure a subset of CS when CS hopping is configured. The subset configuration applies to all ports in the SRS resource, and all ports in the SRS resource have the same hopping offset value on the OFDM symbol. .

[0120] The method may be used to manage inter-TRP cross-SRS interference targeting TDDC JT via SRS interference randomization and / or capacity enhancement using CS hopping.

[0121] The method provides randomized code domain resource mapping for SRS transmission by introducing CS hopping / randomization to SRS resources.

[0122] Fig.17 A wireless network for managing SRS CS resource allocation according to an embodiment is shown.

[0123] refer to Fig.17 , the wireless network can be a 4th generation (4G) network, a 5G network, a 6G network, and an open radio access network (ORAN).

[0124] The wireless network includes a UE (or transmitter) 1710 and a BS (or TRP unit) 1720 (receiver). The UE includes a plurality of UEs (1710a-1710n). The BS 1720 may be a gNB, an eNB, or an NR transceiver. The UE 1710 may be a laptop, a smart phone, a desktop computer, a notebook, a device-to-device (D2D) device, a V2X device, a foldable phone, a smart television (TV), a tablet computer, an immersive device, or an Internet of Things (IoT) device.

[0125] BS 1720 configures CS allocation to at least one port of UE 100. The CS allocation uses a value from a subset of a plurality of allowable CS values.

[0126] BS 1720 distributes a plurality of allowable CS values ​​in a first subset of CS values ​​and a second subset of CS values, and so on, into a plurality of subsets. The first subset of CS values ​​is provided as a set of continuous CS values, and the second subset of CS resources is provided in another set of continuous CS values. In addition, BS 1720 allocates guard bands between the subsets of CS values. CS from these guard bands will not be allocated to any UE. Optionally, the guard band may be zero or non-existent.

[0127] In addition, BS 1720 assigns a CS from each subset of CS values ​​to at least one port of UE 1710. Assigning a CS value from the subset of CS values ​​is explicit for all ports of UE 1710. Alternatively, assigning a CS value from the subset of CS values ​​is for all ports of UE 1710 such that the CS values ​​are equidistant from each other over the subset of CS values.

[0128] UE 1710 is served by a TRP assigned to one subset and by another TRP assigned to another subset. UE 1710 may be a single-port UE. UE 1710 may be a single-port UE and the CS value assigned to UE 1710 does not hop across OFDM symbols. CS allocation to at least one port of UE 1710 may be configured through an RRC message. In addition, BS 1720 causes the assigned CS value to hop to at least one port of UE 1710 within a subset through different OFDM symbols. Hopping across OFDM symbols. Subsets and CS are RRC configured or configured through a medium access control (MAC)-control element (CE) or through downlink control information (DCI).

[0129] BS 1720 may distribute the plurality of allowable CS values ​​into a first subset of CS values ​​and a second subset of CS values, and so on, into a plurality of subsets. Each subset of CS values ​​may be divided into a plurality of subset parts. The number of subset parts is M, and k=cmax / Nap, where cmax is the maximum value of CS or the maximum number of allowable CS, and Nap is the number of ports of UE 1710 that will use the subset. All subset parts will have an equal number of CS values, where CS value a 1 、a 1 +k, ..., a 1 + (Nap-1)*k In the first subset, a 2 、a 2 +k, ..., a 2 + (Nap-1)*k in the second subset, ..., a M 、a M +k, ..., a M+ (Nap-1)*k in the Mth subset part, where M is greater than or equal to 1, where a 1 、a 2 ,……,a M Some, all, or none of the are continuous, and the "+" operation is performed modulo cmax. The combinations of (cmax, Nap) are (12,4), (12,2), (12,1), (8,8), (8,4), (8,2), (8,1), (6,2), (6,1) ... The Nap ports of UE 1710 are assigned values ​​from a subset portion of the subset in any OFDM symbol, for example, Fig.38 The subset and CS can be configured through RRC, MAC-CE or DCI.

[0130] The CS values ​​of Nap ports of UE 1710 may hop within the same subset portion of a given subset across OFDM symbols, or the CS values ​​of Nap ports of UE 1710 may all be within one subset portion of a given subset in a given OFDM symbol, and hop across different subset portions of the same given subset across different OFDM symbols. Alternatively, the CS values ​​of Nap ports of UE 1710 may all be within one subset portion of a given subset in a given OFDM symbol, and hop across different subset portions of different subsets across different OFDM symbols.

[0131] BS 1720 distributes the plurality of allowable CS values ​​into a first subset of CS values ​​and a second subset of CS values, and so on, into a plurality of subsets such that the union of all these subsets is the set of all allowable CS values. The subsets and CS may be configured through RRC, MAC-CE, or DCI.

[0132] The CS value of at least one port of the UE 1710 may hop across OFDM symbols such that each port has a CS value from one subset. The CS value of at least one port of the UE 1710 may hop across OFDM symbols such that each port has a CS value from one subset in some OFDM symbols and a CS value from another subset in other OFDM symbols, etc. The CS value of the port basically hops within different subsets, and these subsets vary in different OFDM symbols.

[0133] The subset may have at least one set of Nap CS values ​​equidistant in the range of 0, ..., cmax-1, where cmax is the maximum number of CS values ​​or the maximum number of allowable CS values, where Nap is the number of ports of the UE, where the CS values ​​of Nap ports of the UE are assigned from one such set from the subset, where the CS values ​​of the ports of the UE jump within the set across OFDM symbols, and where if the subset has more than one such set, the sets may be the same or different across OFDM symbols.

[0134] The CS value assigned to a port may hop within one or more sets of one or more subsets across OFDM symbols. The CS value of at least one port of UE 1710 does not hop across OFDM symbols, and each port has a CS value from one subset. A single-port UE obtains a CS value from one subset and hops within the subset across OFDM symbols.

[0135] A single-port UE may obtain a CS value from one subset and hop between different subsets across OFDM symbols. Alternatively, a single-port UE may obtain a CS value from one subset and not hop across OFDM symbols. For example, consider cmax=12, Nap=2, and the allowable CS is 0-11. In addition, subset 1=CS 0, 6, subset 2=CS 1, 7, 2, 8, subset 3=CS 3, 9, 4, 10, and subset 4=CS 5, 11. In one embodiment, there are four SRS OFDM symbols, and in the first OFDM symbol, CS 1, 7 are assigned to two ports of the UE. In the second OFDM symbol, CS 7, 1 are assigned to the port. In the third OFDM symbol, CS 1, 7 are assigned to two ports of the UE. In the fourth OFDM symbol, CS 7, 1 are assigned to the port.

[0136] In another embodiment, there are four SRS OFDM symbols, and in the first OFDM symbol, CS 1, 7 are assigned to two ports of the UE. In the second OFDM symbol, CS 7, 1 are assigned to ports. In the third OFDM symbol, CS 2, 8 are assigned to two ports of the UE. In the fourth OFDM symbol, CS 8, 2 are assigned to ports.

[0137] In another embodiment, there are four SRS OFDM symbols, and in the first OFDM symbol, CS 1, 7 are assigned to two ports of the UE. In the second OFDM symbol, CS 9, 3 are assigned to ports. In the third OFDM symbol, CS 2, 8 are assigned to two ports of the UE. In the fourth OFDM symbol, CS 10, 4 are assigned to ports.

[0138] In a single-port UE, for example, consider cmax=12, Nap=2, and the allowable CS is 0-11. There are three subsets. Subset 1 - CS 0, 3, 4, 10, 11. Subset 2 = CS 1, 5, 6, Subset 3 = CS 2, 7, 8, 9.

[0139] In one embodiment, a single-port UE has CS 0, 4, 3, 11 in the first four OFDM symbols. In another embodiment, a single-port UE has CS 0, 10, 11 in the first three OFDM symbols, and CS 6 in the fourth OFDM symbol, and CS 7, 2 in the following OFDM symbols.

[0140] In another embodiment, BS 1720 defines multiple UEs 1710 associated with the TRP unit as UEG. UEG includes multiple RGs, and each RG uses the same comb and maximum CS value. In addition, BS 1720 determines the maximum value of the expected BW of each UE according to UEG. BS 1720 determines the interference BW of multiple UEs 1710.

[0141] In addition, BS 1720 sorts multiple UEs 1710 in UEG belonging to one TRP unit in descending order of the maximum value of their distances to other TRPs. BS 1720 allocates multiple sorted UEs 1710 in UEG and allocates them to one comb starting from the first UE in the sorted group. The allocated UEs 1710 hop across different combs in different OFDM symbols.

[0142] In addition, BS 1720 collects the remaining UEs from UEG across TRPs after allocation and assigns the remaining UEs to the same comb, so that the UEs of each TRP are allocated different subsets of continuous CS resource values ​​and the CS values ​​of these UEs jump within the subset of CS resource values ​​across different OFDM symbols.

[0143] By using the allocated CS, the BS 1720 receives the SRS.

[0144] BS 1720 may perform CS hopping within a subset of allowable CS. The subset is formed by the entire allowable CS value. BS 1720 determines that the CS value for a given port of UE 1710 at a given OFDM symbol is at the edge of the CS-TRP-R. In addition, BS 1720 silences or does not send SRS for the port of UE 1710 at the OFDM symbol. In addition, when it is determined that UE 1710 is a multi-port UE, BS 1720 transfers the transmission power of the port of UE 1710 to other ports of the same UE.

[0145] BS 1720 may mute SRS transmission. BS 1720 may allocate CS values ​​to UE 1710 in different combs and the same OFDM symbol. BS 1720 may allocate CS resources to UE 1710 in the same comb and OFDM symbol.

[0146] BS 1720 may configure at least one of the plurality of transmitters and at least one port of the plurality of transmitters to transmit pilots on at least one of the same frequency and time resources. In addition, BS 1720 may determine a number of transmitters or ports of the transmitters. BS 1720 calculates the subcarriers and pilots used in a rectangular grid of pilot subcarriers for transmission. In addition, BS 1720 calculates the pseudo-inverse of an all-user (e.g., UE) vectorized basis matrix. In addition, BS 1720 calculates the product of the calculated pseudo-inverse of the all-user vectorized basis matrix and the vector of received values ​​on the pilot subcarriers, or the product of the pre-stored pseudo-inverse of the all-user vectorized basis matrix and the vector of received values ​​on the pilot subcarriers to obtain an estimate of an all-user basis coefficient vector. BS 1720 extracts a user basis coefficient vector for each UE from the estimated all-user basis coefficient vector. In addition, BS 1720 determines an estimate of the channel on a rectangular grid of subcarriers for each transmitter based on the user basis coefficient vectors and the estimated full user basis coefficient vectors.

[0147] BS 1720 may determine the number of UEs corresponding to the SRS. Based on the determination, BS 1720 calculates the number of SRS subcarriers. BS 1720 generates a reference sequence matrix corresponding to the UE using the ZC sequence and the CS value. The reference sequence matrix corresponding to the UE is generated by selecting at least one of the Slepian technique, the polynomial technique, the DFT technique, or any other basis (such as DCT, oversampled DFT, Karhunen-Loeve, etc.).

[0148] In addition, BS 1720 monitors the vector value of the reference sequence matrix on at least one SRS subcarrier. BS 1720 calculates the pseudo-inverse of the concatenated matrix. BS 1720 calculates a predefined SRS vector and the calculated pseudo-inverse of the concatenated basis matrix or one of the pre-stored pseudo-inverses of the concatenated basis matrix to obtain an estimate of the concatenated basis coefficient vector. BS 1720 extracts the user basis coefficient vector of each UE from the estimated concatenated basis coefficient vector. In addition, BS 1720 determines a channel estimate for each UE based on the user basis coefficient vector and the estimated concatenated basis coefficient vector.

[0149] Fig.18 A BS (or TRP unit) according to an embodiment is shown.

[0150] refer to Fig.18 , the BS includes a processor 1810, a communicator 1820, a memory 1830, and an SRS resource allocation controller 1840. The processor 1810 is coupled to the communicator 1820, the memory 1830, and the SRS resource allocation controller 1840. However, the components of the BS are not limited thereto. For example, the BS may include Fig.18 More or fewer components than those shown.

[0151] The SRS resource allocation controller 1840 configures a CS allocation to at least one port of the UE. The CS allocation uses a value from a subset of a plurality of allowable CS values.

[0152] The SRS resource allocation controller 1840 distributes a plurality of allowable CS values ​​in a first subset of CS values ​​and a second subset of CS values. The first subset of CS values ​​is provided as continuous CS values, and the second subset of CS resources is provided as different continuous CS values. In addition, the SRS resource allocation controller 1840 allocates guard bands between subsets of CS values. The SRS resource allocation controller 1840 allocates CS to at least one port of the UE from each subset of CS values. The allocation of CS values ​​from a subset of CS values ​​may be explicit for all ports of the UE, or the allocation of CS values ​​from a subset of CS values ​​is for all ports of the UE, so that these CS values ​​are equidistant from each other on the subset of CS values. The UE is served by a TRP assigned to one subset and by another TRP assigned to another subset.

[0153] The UE may be a single-port UE, and the CS value assigned to the UE does not hop across OFDM symbols. The CS allocation to at least one port of the UE may be configured through an RRC message.

[0154] In addition, the SRS resource allocation controller 1840 causes the assigned CS value to hop to at least one port of the UE within the subset. The hopping spans across OFDM symbols.

[0155] The BS distributes the plurality of allowable CS values ​​into a first subset of CS values ​​and a second subset of CS values, and so on, into a plurality of subsets. Each subset of CS values ​​may be divided into a plurality of subset parts. The number of subset parts is M, and k=cmax / Nap, where cmax is the maximum value of CS or the maximum number of allowable CS, and where Nap is the number of ports of UEs that will use the subset. All subset parts will have an equal number of CS values, where CS value a 1 、a 1 +k, ..., a 1+ (Nap-1)*k in the first subset, a2, a2+k, ..., a2+ (Nap-1)*k in the second subset, ..., a M 、a M +k, ..., a M + (Nap-1)*k in the Mth subset part, where M is greater than or equal to 1, where a 1 、a 2 ,……,a M Some, all, or none of them are continuous, and the "+" operation is performed modulo cmax. The combinations of (cmax, Nap) are (12,4), (12,2), (12,1), (8,8), (8,4), (8,2), (8,1), (6,2), (6,1)... The Nap ports of the UE are assigned a value from a subset portion of the subset in any OFDM symbol. The subset and CS can be configured by RRC, MAC-CE or DCI.

[0156] The CS values ​​of Nap ports of the UE may hop within the same subset portion of a given subset across OFDM symbols. The CS values ​​of Nap ports of the UE may all be within a subset portion of a given subset in a given OFDM symbol, and hop across different subset portions of a given subset across different OFDM symbols. The CS values ​​of Nap ports of the UE may all be within a subset portion of a given subset in a given OFDM symbol, and hop across different subset portions of different subsets across different OFDM symbols.

[0157] The BS distributes a plurality of allowable CS values ​​in a first subset of CS values ​​and a second subset of CS values, and so on, into a plurality of subsets such that the union of all these subsets is a set of all allowable CS values. The CS value of at least one port of the UE hops across OFDM symbols such that all ports have CS values ​​from one subset. Alternatively, the subset has at least one set of Nap CS values ​​equidistant in the range of 0, ..., cmax-1, where cmax is the maximum number of CS values ​​or the maximum number of allowable CS values, where Nap is the number of ports of the UE, where the CS values ​​of Nap ports of the UE are assigned from one such set from the subset, where the CS values ​​of the ports of the UE hop within the set across OFDM symbols, and where if the subset has more than one such set, the sets may be the same or different across OFDM symbols.

[0158] The CS value assigned to a port can hop within one or more sets of one or more subsets across OFDM symbols. The CS value of at least one port of the UE does not hop across OFDM symbols, and each port has a CS value from a subset. A single-port UE obtains a CS value from a subset and hops within the subset across OFDM symbols. Alternatively, a single-port UE obtains a CS value from a subset and hops between different subsets across OFDM symbols.

[0159] A single-port UE can obtain a CS value from a subset and does not jump across OFDM symbols. For example, consider cmax=12, Nap=2, and the allowable CS is 0-11. In addition, subset 1=CS 0, 6, subset 2=CS 1, 7, 2, 8, subset 3=CS 3, 9, 4, 10 and subset 4=CS 4, 11. In one embodiment, there are four SRS OFDM symbols, and in the first OFDM symbol, CS 1, 7 are assigned to the two ports of the UE. In the second OFDM symbol, CS 7, 1 are assigned to the port. In the third OFDM symbol, CS 1, 7 are assigned to the two ports of the UE. In the fourth OFDM symbol, CS 7, 1 are assigned to the port.

[0160] In another embodiment, there are four SRS OFDM symbols, and in the first OFDM symbol, CS 1, 7 are assigned to two ports of the UE. In the second OFDM symbol, CS 7, 1 are assigned to ports. In the third OFDM symbol, CS 2, 8 are assigned to two ports of the UE. In the fourth OFDM symbol, CS 8, 2 are assigned to ports.

[0161] In another embodiment, there are four SRS OFDM symbols, and in the first OFDM symbol, CS 1, 7 are assigned to two ports of the UE. In the second OFDM symbol, CS 9, 3 are assigned to ports. In the third OFDM symbol, CS 2, 8 are assigned to two ports of the UE. In the fourth OFDM symbol, CS 10, 4 are assigned to ports.

[0162] The SRS resource allocation controller 1840 defines multiple UEs associated with a TRP unit as a UEG. The UEG includes multiple RGs, and each RG uses the same comb and maximum CS value. In addition, the SRS resource allocation controller 1840 determines the maximum value of the expected BW of each UE based on the UEG. In addition, the SRS resource allocation controller 1840 determines the interference BW of multiple UEs. The SRS resource allocation controller 1840 sorts multiple UEs in the UEG belonging to one TRP unit in descending order of the maximum value of their distances to other TRPs. The SRS resource allocation controller 1840 allocates multiple sorted UEs in the UEG and allocates them to one comb starting from the first UE in the sorted group. The allocated UEs jump across different combs in different OFDM symbols.

[0163] In addition, the SRS resource allocation controller 1840 collects the remaining UEs from the UEG across TRPs after allocation and assigns the remaining UEs to the same comb, so that the UEs of each TRP are allocated different subsets of continuous CS resource values, and the CS values ​​of these UEs jump within the subset of CS resource values ​​across different OFDM symbols.

[0164] By using the allocated CS, the SRS resource allocation controller 1840 receives the SRS.

[0165] The SRS resource allocation controller 1840 performs CS hopping within a subset of the allowable CS. A subset is provided over the entire allowable CS value. The SRS resource allocation controller 1840 determines that the CS value for a given port of the UE at a given OFDM symbol is at the edge of the CS-TRP-R. In addition, the SRS resource allocation controller 1840 silences or does not send SRS for the port of the UE at the OFDM symbol. When it is determined that the UE is a multi-port UE, the SRS resource allocation controller 1840 transfers the transmission power of the port of the UE to other ports of the same UE.

[0166] The SRS resource allocation controller 1840 mutes SRS transmission. Alternatively, the SRS resource allocation controller 1840 allocates CS values ​​to UEs in different combs and the same OFDM symbol. The SRS resource allocation controller 1840 allocates CS resources to UEs in the same comb and OFDM symbol.

[0167] The pilot receiver 1850 configures at least one of the multiple transmitters and at least one port of the multiple transmitters to transmit a pilot on at least one of the same frequency and time resources. The pilot receiver 1850 determines the multiple transmitters or the ports of the transmitters. The pilot receiver 1850 calculates the subcarriers and pilots used in the rectangular grid of pilot subcarriers for transmission. The pilot receiver 1850 calculates the pseudo-inverse of the full UE vectorization basis matrix. The pilot receiver 1850 calculates the product of the calculated pseudo-inverse of the full user vectorization basis matrix and the vector of the received values ​​on the pilot subcarriers, or the product of the pre-stored pseudo-inverse of the full user vectorization basis matrix and the vector of the received values ​​on the pilot subcarriers to obtain an estimate of the full user basis coefficient vector. The pilot receiver 1850 extracts the user basis coefficient vector of each UE from the estimated full user basis coefficient vector. In addition, the pilot receiver 1850 determines an estimate of the channel on the rectangular grid of the subcarriers of each transmitter based on the user basis coefficient vector and the estimated full user basis coefficient vector.

[0168] At least one of the configured multiple transmitters and at least one port of the transmitter sends a pilot on the configured time and frequency resources, so that the index of the mg-vector (mg-vector) used as the exponential complex sequence in the frequency domain for various transmitters and / or ports of the transmitter is a, a-2b and a-4b, where a is 0, an integer, a fraction, or a fraction plus an integer, and b is the perceived bandwidth of the channel of the receiver in the frequency domain.

[0169] The indices of the mg vector used as the exponential complex sequence in the time domain for the various transmitters and / or ports of the transmitter are a, a-2b, and a-4b, where a is 0, an integer, a fraction, or a fraction plus an integer, and b is the perceived bandwidth of the channel in the time domain at the receiver. The perceived bandwidth of the channel in both the frequency and time domains is based on the channel estimation module of the receiver.

[0170] The full user vectorized basis matrix may be generated by using one of a Slepian sequence, a polynomial sequence, and a DFT-based sequence.

[0171] The pilot receiver 1850 determines the number of UEs corresponding to the SRS. Based on the determination, the pilot receiver 1850 calculates the number of SRS subcarriers. The pilot receiver 1850 generates a reference sequence matrix corresponding to the UE using the ZC sequence and the CS value. The reference sequence matrix corresponding to the UE is generated by selecting at least one of the Slepian technique, the polynomial technique, the DFT technique, or any other basis (such as DCT, oversampled DFT, Karhunen-Loeve, etc.).

[0172] In addition, the pilot receiver 1850 monitors the vector value of the reference sequence matrix on at least one SRS subcarrier. The pilot receiver 1850 calculates the pseudo-inverse of the splicing matrix. The pilot receiver 1850 calculates the predefined SRS vector and the calculated pseudo-inverse matrix of the splicing basis matrix or one of the pre-stored pseudo-inverse matrices of the splicing basis matrix to obtain an estimate of the splicing basis coefficient vector. The pilot receiver 1850 extracts the user basis coefficient vector of each UE from the estimated splicing basis coefficient vector. The pilot receiver 1850 determines the channel estimate of each UE based on the user basis coefficient vector and the estimated splicing basis coefficient vector.

[0173] The SRS resource allocation controller 1840 may be implemented by analog and / or digital circuits (such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hard-wired circuits, etc.) and may optionally be driven by firmware.

[0174] The pilot receiver 1850 may be implemented by analog and / or digital circuits (such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hard-wired circuits, etc.) and may optionally be driven by firmware.

[0175] The processor 1810 may include one or more processors. The one or more processors may include a general-purpose processor (such as a central processing unit (CPU), an application processor (AP), etc.), a graphics processing unit (such as a graphics processing unit (GPU), a visual processing unit (VPU)), and / or an AI-specific processor (such as a neural processing unit (NPU)). The processor 1810 may include multiple cores and is configured to execute instructions stored in the memory 1820.

[0176] The processor 1810 may be configured to execute instructions stored in the memory 1830 and perform various processes.

[0177] The communicator 1820 may be configured for internal communication between internal hardware components and with external devices via one or more networks.

[0178] Memory 1830 may store instructions to be executed by processor 1810. Memory 1830 may include non-volatile storage elements, such as a magnetic hard disk, an optical disk, a floppy disk, a flash memory, or an electrically programmable memory (EPROM) or an electrically erasable programmable (EEPROM) memory. In addition, memory 1830 may be considered a non-transitory storage medium. The term "non-transitory" may indicate that the storage medium is not embodied in a carrier wave or a propagating signal. However, the term "non-transitory" should not be interpreted to mean that memory 1830 is non-removable. Non-transitory storage media may store data that may change over time (e.g., in RAM or cache).

[0179] although Fig.18 Various hardware components of the BS are shown, but other embodiments are not limited thereto. For example, the BS may include fewer or more components. In addition, the labels or names of the components are only for illustrative purposes and do not limit the scope of the present disclosure. One or more components may be combined together to perform the same or substantially similar functions in the BS. The BS may also include an SRS receiver or an OTFS receiver for receiving a pilot such as an SRS / DMRS or any pilot set on a rectangular time-frequency grid.

[0180] Fig.19 is a flow chart illustrating a method for managing SRS CS resource allocation in a wireless network according to an embodiment.

[0181] refer to Fig.19 In step 1902, the BS configures CS allocation to at least one port of at least one UE. The CS allocation uses a value from a subset of multiple allowable CS values, and the CS allocated to at least one port of at least one UE hops within the subset of CS values ​​for each OFDM symbol.

[0182] In step 1904, the BS receives the SRS using the allocated CS.

[0183] Fig. 20 is a flow chart illustrating a method for channel estimation in a wireless network according to an embodiment.

[0184] refer to Fig. 20 In step 2002, the BS configures at least one of the plurality of transmitters and at least one port of the plurality of transmitters to transmit a pilot on at least one of the same frequency and time resources.

[0185] In step 2004, the BS determines a plurality of transmitters or ports of transmitters.

[0186] In step 2006, the BS calculates subcarriers and pilots used in a rectangular grid of pilot subcarriers for transmission.

[0187] In step 2008, the BS calculates the pseudo-inverse of the full-user quantization basis matrix.

[0188] In step 2010, the BS calculates the product of the calculated pseudo-inverse of the full-user quantization basis matrix and the vector of received values ​​on the pilot subcarriers, or the product of the pre-stored pseudo-inverse of the full-user quantization basis matrix and the vector of received values ​​on the pilot subcarriers to obtain an estimate of the full-user basis coefficient vector.

[0189] In step 2012, the BS extracts a user basis coefficient vector for each UE from the estimated full user basis coefficient vector.

[0190] In step 2014, the BS determines an estimate of the channel on a rectangular grid of subcarriers for each transmitter based on the user basis coefficient vectors and the estimated full user basis coefficient vectors.

[0191] Fig.21 is a flow chart illustrating a method for channel estimation in a wireless network according to an embodiment.

[0192] refer to Fig.21 , in step 2102, the BS determines the number of UEs corresponding to the SRS.

[0193] In step 2104, the BS calculates the number of SRS subcarriers based on the determination.

[0194] In step 2106, the BS generates a reference sequence matrix corresponding to the plurality of UEs using the ZC sequence and the CS value of each UE.

[0195] In step 2108, the BS monitors the vector value of the reference sequence matrix on at least one SRS subcarrier. In step 2110, the BS calculates the pseudo-inverse of the concatenated basis matrix. In step 2112, the BS calculates the product of the calculated pseudo-inverse of the concatenated basis matrix and the SRS vector of the received SRS value, or the product of the pre-stored pseudo-inverse of the concatenated basis matrix and the SRS vector of the received SRS value to obtain an estimate of the concatenated basis coefficient vector.

[0196] In step 2114, the BS extracts the user basis coefficient vector of each UE from the estimated concatenated basis coefficient vector.

[0197] In step 2116, the BS determines a channel estimate for each UE based on the user basis coefficient vector and the estimated concatenated basis coefficient vector.

[0198] Fig. 22 A method of CS allocation according to an embodiment is shown.

[0199] refer to Fig. 22,Per-port CS allocation gives the flexibility to efficiently use CS resources to minimize inter-TRP interference.

[0200] Fig.23 A method of CS allocation according to an embodiment is shown.

[0201] refer to Fig.23 , if the UE of another TRP needs to be decoded by the given TRP, further processing should be performed. The first TRP estimates the channel of its own UE and then cancels the estimate of the received signal of its own UE from its received signal. This signal can be called RSOUE. This process can be called first interference cancellation. The first TRP then uses RSOUE to estimate the channel of the UE from the other TRP. Assume that the timing offset of the two UEs from the other TRP to the desired TRP is t 1 and t 2 , and when t 1 and t 2 When both are greater than zero, the channels of the two UEs overlap, and TRP multiplies RSOUE by where a=t 2 (Assuming t 1 >t 2 ), so that the dispersion of the channels seen by the desired TRP of the UE of the other TRP is reduced. More importantly, the two channels are now non-overlapping and can be estimated. The estimated channel is then multiplied by to obtain the desired channel estimate, where a can be a universal value for channel estimation for any set of UEs from interfering / other TRPs at the desired / own TRP.

[0202] In another embodiment, assume that there are x UEs per TRP and there are two TRPs. The FFT BW seen by the UE's own TRP is a, and the FFT BW seen by the other TRP is b. If the UEs should not interfere with each other and are allocated according to the traditional equidistant CS, the total BW is L BW =xa+xb<=c max .

[0203] In the case where CS is configured per port, the total BW is P BW =2xa+2(ba)<=c max . Note that L BW -P BW >0, because L BW -P BW =(x-2)(ba) and x>2, b>a. Therefore, the proposed method utilizes resources efficiently.

[0204] Fig.24 is a graph showing the improvement in the capacity of the receiver.

[0205] refer to Fig.24 , capacity improvement is also one of the goals for SRS [Reference: RP-213591, "New WID: MIMO Evolution for Downlink and Uplink"]. The number of UEs using the same time-frequency resources is a function of the delay spread of the channel. In existing standards, the number of UEs is a function of the comb size or kTC. If kTC=2, there are four UEs. According to existing standards, there may be only four UEs, but advanced receivers can accommodate 6 UEs, so there should be provisions in the standard to do so, such as Fig.24 shown.

[0206] For kTC = 2, (combsize) c max (Maximum CS) is 8, but when the maximum CS is 8, the 6 UEs cannot be evenly distributed among the CSs. Without even distribution of CSs, there is a performance loss. Therefore, the maximum CS c max It should also be configurable. Therefore, there should also be a mechanism, for example, via RRC messages, for configuring the value of the maximum CS independently of the kTC.

[0207] Fig.25 The allocation of CS to UE according to an embodiment is shown.

[0208] refer to Fig.25 , the technique consists of assigning all UEs of a TRP in a continuous manner, followed by a gap, followed by all UEs of another TRP, and so on, followed by another gap, and so on, until all CSs are exhausted.

[0209] Fig.26 The allocation of CS to UE according to an embodiment is shown.

[0210] refer to Fig.26 , the CS domain is divided into multiple regions. Every two regions are separated by a guard band, which can optionally have a zero CS value. The regions (TRP1 and TRP2) are assigned to UEs of TRP1 and TRP2 respectively. CS allocation per port configuration can also be performed as follows. The method assigns TRP1 to UEs belonging to TRP1 and TRP2 to UEs belonging to TRP2. For example, this can be done via an RRC message. Within each region, the ports of the UE can be allocated equidistantly. Only signaling notifies the start. If necessary, the region wraps around. The UE of the network can set the starting position and increment to cover all ports of the UE.

[0211] The following techniques can be performed for resource allocation:

[0212] a) Define all UEs associated with a TRP as UEGs.

[0213] b) A UEG can have multiple RGs.

[0214] c) Each RG uses the same comb, the same c max .

[0215] d) Determine the maximum value of the expected BW for each UEG.

[0216] e) Determine the interference BW of all UEs.

[0217] f) Arrange the UEs in UEG in descending order of their distances to other TRPs.

[0218] g) Assign all UEs in a UEG (preferring the UE with the largest distance to other TRPs) to a comb such that the difference in CS between two UEs is less than the maximum value of the expected BW of the UEs in that comb. Repeat this process for all UEGs. Use an appropriate comb length or C max .

[0219] h) For the remaining UEs in UEG of different TRPs, the method accommodates them in the same comb with appropriate guard bands. Such a comb is called a hybrid comb. This comb will have UEs belonging to other TRPs.

[0220] i) In hybrid comb, the guard band can be less than half the difference between the interference BW and the desired BW. In this case, the method includes CS hopping and / or comb hopping to reduce interference.

[0221] j) For CS hopping, the CSs of some, all or only edge UEs hop among themselves.

[0222] k) For comb hopping, RG hops within one comb or across all combs to reduce interference.

[0223] l) The above algorithm is for one instant in time. The algorithm can also be run for various time instances to multiplex multiple UEGs / UEs in time.

[0224] In addition, conventional SRS receivers are based on a Fourier basis, similar to that described in [“DMRS Design and Channel Estimation for LTE-Advanced MIMO Uplink”, IEEE 2009 Vehicular Technology Conference]. Conventional receivers based on the Fourier basis exhibit the Gibbs problem. However, a good basis can approximate the channel with less error and fewer basis coefficients. Therefore, the Fourier basis is not the best in this case. For example, there are better bases such as polynomials or Slepian.

[0225] make for Observe the SRS vector (the values ​​observed on the N SRS subcarriers or SRS REs). Let us consider Basis Matrix and Basis coefficient vector The UE of the BS can observe the channel vector Approximations are made as follows.

[0226] Fourier and Slepian

[0227] and .

[0228] Notice, is a unitary matrix, that is, (the identity matrix), and It is estimated to be .

[0229] Polynomial

[0230] E and .

[0231] here, is not a unitary matrix. It is estimated to be For example, if Yes 24 ,but Cannot be greater than 6 to ensure The good condition number.

[0232] instruct Before columns and subscripts Denotes F, P, S (Fourier, Slepian, and polynomial basis).

[0233] Likewise, instruct Before elements and subscripts Denotes F, P, S (Fourier, Slepian, and polynomial basis).

[0234] The channel reconstruction error for each of the bases (Fourier, Polynomial, and Slepian) can be defined as shown in equation (1).

[0235]

[0236] … (1)

[0237] As will be described below, the UE of the BS requires more basis coefficients at a higher reconstruction error than the Fourier basis of the polynomial and Slepian basis. < have < .

[0238] quantity < ) may also be important in other ways. Small values ​​may help improve capacity. UEs are using the same time-frequency SRS RE, then . Therefore, if the complexity is the same as the Fourier basis, other bases can be considered for performance / capacity improvement.

[0239] For the Fourier and Slepian bases, ,because is a unitary matrix. For a polynomial basis, , because from is not a unitary matrix.

[0240] To model the channel well, for small values ​​of R, the UE of the BS may wish to For capacity improvement, smaller values ​​may be preferred because the UE has .

[0241] Therefore, UE defines the quantity .

[0242] if For small R values ​​up to 1, it is a good choice of basis.

[0243] In summary, the following two points are important for the basis.

[0244] a) For small R values ​​it reaches 1.

[0245] b) For smaller R values ​​it is small.

[0246] Basis Matrix

[0247] a) Fourier- Elements by Given.

[0248] b) Polynomial- Elements by Given.

[0249] c) The Slepian-Slepian sequence is given by Characterization, is the time half-bandwidth product.

[0250] Slepian Method : The Slepian sequence has the smallest leakage among all the sequences based on Tables 1 and 2 below.

[0251]

[0252] Table 1

[0253]

[0254] Table 2

[0255] Slepian (DPSS) base

[0256] a) yes matrix( orthogonal columns), which can be obtained by matlab dpss( , thbw, ) function. The generated length is (First parameter) (Third parameter) sequence. thbw is called time half bandwidth (time_halfbandwidth).

[0257] Fig. 27 is a diagram showing the Gibbs phenomenon.

[0258] refer to Fig. 27 , the Fourier basis means there are more errors at the edges, which is called the Gibbs phenomenon. There is no such problem for the Slepain and polynomial basis.

[0259] Figures 28 to 30is a diagram illustrating a comparison of metrics according to an embodiment.

[0260] refer to Figures 28 to 30 , for a given R, compared to the Fourier basis, Slepain and polynomial basis Smaller. For a given , Slepain and polynomial bases have smaller R than Fourier bases. For Slepian and polynomial bases, Get there faster.

[0261] Fig.31 and Fig.32 is a graph showing performance comparison according to an embodiment.

[0262] The proposed receiver :against The channel estimation of each SRS UE uses the same time-frequency resource. Let the channel vector of the i-th UE be given by Vector representation.

[0263]

[0264] … (2)

[0265] In equation (2), is the basis matrix, the subscript M indicates the choice of method, and the basis coefficient vector of the i-th UE is Depend on Denotes , which is called the i-th UE basis coefficient vector.

[0266] The concatenated basis matrix is ​​expressed as ,in, is the concatenation of the basis coefficient vectors of all UEs, which is called the concatenated basis coefficient vector, ,in, is the reference sequence (ZC sequence and CS index) of the i-th user along the diagonal Diagonal matrix.

[0267] generally, , ……, The ZC components in are the same. Here, z is a diagonal matrix with ZC sequences on the diagonal. Definition and .Notice, , ……, In A, if constructed without the ZC sequence but only with the index CS, it becomes .

[0268] In the receiver, the UE has And will Estimated If the ZC component is the same in all UEs, then and .

[0269] according to , this method can be used to calculate and estimate as well as .

[0270] Complexity

[0271] a) Consider the maximum CS of eight and four UEs.

[0272] b) Case 1: CS=0, 2, 4, 6.

[0273] c) Case 2: CS=1, 3, 5, 7.

[0274] d) This method assumes equidistant CSs, although this need not be the case, as long as the differences between the CSs are the same.

[0275] e) Order and is the A matrix for Case 1 and Case 2 above.

[0276] f) This method can be observed and are identical and can be pre-computed and stored, and furthermore do not depend on the ZC sequence.

[0277] g) ,in, is a diagonal matrix with the exponential sequence corresponding to the CS differences (in this case the identity sequence).

[0278] h) can be precomputed and can be calculated.

[0279] i) The method can be easily implemented. Similar analysis applies to .

[0280] This method can be used to extend to any Rx of any channel, not just SRS receiver. This method can also be used for physical downlink shared channel (PDSCH) receiver / physical uplink shared channel (PUSCH) receiver. Base matrix Can be from any basis like Slepian, Polynomial, DFT, Oversampled DFT, DCT, Karhunen-Loeve or any other basis.

[0281] Fig.33The allowable CS divided into two subsets and the CS values ​​associated with the ports hopping within the subsets across OFDM symbols are shown according to an embodiment.

[0282] refer to Fig.33 , the UEs of each TRP may be given a continuous non-overlapping region of CS, e.g. a CS-TRP-Region (or CS-TRP-R). Only UEs associated with a CS at the right edge of the CS-TRP-R experience interference from UEs of other TRPs. UEs associated with a CS not at the right edge of the CS-TRP-R do not experience interference from UEs of other TRPs. Fig.33 In FIG, the non-highlighted blocks represent UEs with CS without interference from other TRPs. The highlighted blocks are the edges of CS-TRP-R.

[0283] Fig.34 The allowable CS divided into two subsets and the CS values ​​associated with the ports hopping and muting within the subsets across OFDM symbols are shown according to an embodiment.

[0284] refer to Fig.34 , the CS of the UE jumps within the CS-TRP-R. In this way, all UEs share the interference equally. When the CS of a user is at the edge of the CS-TRP-R, it is muted and not transmitted in that OFDM symbol. In this way, the performance almost reaches the case of a single TRP (no interference from mTRP), and almost all interference is removed.

[0285] Each TRP has two UEs. The desired CS of the UEs in a TRP is denoted by d 1 and d 2 The CS of the UE in the interfering TRP is represented by i 1 、i 2 The signal from the UE interfering with the TRP travels an additional propagation distance of 300 m, as shown in Tables 3 to 7 below.

[0286] Table 3

[0287]

[0288] Table 4: CS allocation of traditional scheme

[0289]

[0290] Table 5: Proposed per-port solutions

[0291]

[0292] Table 6: Proposed per-port solutions

[0293]

[0294] Table 7: Results

[0295]

[0296] In Table 4 above, legacy CS allocation (hopping) is an example of CS values ​​assigned to ports of a UE, and these CS values ​​are taken from a subset of allowable CS values ​​and hop across OFDM symbols. Although one hopping pattern is provided as an example, other hopping patterns are possible.

[0297] The table in Table 7 below can be a Figure 35 to Figure 37 The per-port CS transitions and silences can be considered as a simplified time division multiplexing (TDM) as follows.

[0298] Consider four UEs sharing 12 CSs in each of four OFDM symbols, which results in interference to half of the UEs in any OFDM symbol. 1 =0,d 2 =3,i 1 =3,i 2 =6.d 2 and i 2 Each UE has power P. Therefore, only d 1 =0 and i 1 = 6 with power 2P, and in the next two OFDM symbols d 2 =0 and i 2 =6 has power 2P, thus avoiding interference completely because the CS is separated by six cells. The reduced processing gain due to each UE being present in only half of the OFDM symbols is well compensated by increasing the power to twice the usual. This is an alternative view of per-port CS with hopping and muting. Note that the TD-OCC scheme (if any) will fail due to muting / dropping of SRS in one of the OFDM symbols.

[0299] Only the UE whose CS is at the right edge of the CS-TRP-R is muted. It is muted at the left edge of the CS-TRP-R, and can also be muted at both edges of the CS-TRP-R.

[0300] The kTC may be configured independently. The maximum CS may also be configured independently (i.e., not dependent on the kTC according to existing standards). A fixed or random hopping pattern may be used. The random hopping pattern may be based on a pseudo-random sequence, a network-configured identifier (ID) with a UE-specific implementation, etc. Different UEs may also indicate different antenna ports for a single UE, and vice versa.

[0301] exist Fig.34 In the example, only UEs associated with the CS at the right edge of the CS-TRP-R experience interference from UEs of other TRPs. UEs associated with the CS not at the right edge of the CS-TRP-R do not experience interference from UEs of other TRPs.

[0302] Figure 35 to Figure 37 is a diagram showing a performance comparison between a CS resource allocation method according to an embodiment and a conventional CS resource allocation method.

[0303] refer to Figure 35 to Figure 37 , muting refers to CS hopping across OFDM symbols for UEs, which are dropped or not sent in OFDM symbols where CS is at the edge of CS-TRP-R. However, muting does not need to be implemented as the gNB can choose to ignore SRS in this case. However, by muting, additional power is delivered to other UEs, which improves performance. Fig.37 In the example, per-port CS with hopping improves the performance. Per-port CS with hopping and silence further improves the performance and achieves the lower bound of a single TRP (no interference case).

[0304] Fig.38 A method of forming a subset from a set of allowable CS values ​​according to an embodiment is shown.

[0305] refer to Fig.38 , hopping and traditional CS outperform traditional CS without hopping. In addition, hopping and per-port CS outperform per-port CS without hopping. Hopping always improves performance independently of traditional CS or per-port CS.

[0306] Per-port CS with hopping and silence almost achieves the lower limit of the single TRP and no-interference case.

[0307] ZC sequence, CS and exponential sequence:

[0308]

[0309] … (3)

[0310] In equation (3), is the Hadamard product or element-wise multiplication operation, yes Zadoff chu sequence vector, and is the exponential complex sequence vector given by equation (4).

[0311]

[0312] … (4)

[0313] In equation (4), .here, is called CS, although the 3GPP standard It is called CS. UE uses As N. Note that It is called the maximum CS or the maximum number of CS allowed.

[0314] Timing offset compensation:

[0315] If there is a timing offset (It may be different for different UEs, but is the same for all ports. If a UE is involved, the UE uses one value which is either the maximum or an intermediate value for all possible UEs).

[0316] Therefore, the kth RE (resource element) will thereby undergo a phase change which is ,in, is the subcarrier spacing. The compensated timing offset vector It is constructed as shown in equation (5).

[0317]

[0318] … (5)

[0319] The received signal vector y is pre-compensated as y=diag( , as a first step before further processing in the SRS receiver. Diag(x) is a diagonal matrix with the vector x along the main diagonal.

[0320] Slepian sequence-time half-bandwidth product

[0321] Consider a discrete signal And let its discrete time Fourier transform (DTFT) be expressed by equation (6).

[0322]

[0323] … (6)

[0324] In equation (6), That is, the signal is bandwidth-limited to and In this case, the UE can consider Located by In the subspace spanned by the Slepian (discrete prolate spheroidal sequence) basis, for different n, each basis is composed of modulation.

[0325] Consider multiple multipaths, the first one is t 1 , the last one is t 2 The channel of the kth SRS subcarrier among the N SRS subcarriers is given by (for simplicity, assuming kTC=1) equation (7).

[0326]

[0327] … (7)

[0328] In equation (7), is the subcarrier spacing and the signal Limited by bandwidth and Between. Definition , , Along the main diagonal The diagonal matrix of .Then, Located in Dimension The time half-bandwidth product is , and the parameter NW is in the matlab function dpss. Here, is called the mg vector and g is the index into the mg vector.

[0329] Perceived Bandwidth

[0330] Channel With bandwidth If the method is DTFT, Perceptual Bandwidth (PBW) will be greater than ,For example, This is because of the window effect and the finite size N. As N increases, , but for small N, Therefore, the number of multiple users that make the DTFTs non-overlapping (this method uses CS or exponential sequences to shift and ensure that the DTFTs of the UEs do not overlap) is .

[0331] Ideally, By definition, a Slepian sequence of length N is in the frequency domain to The sequence with the largest energy concentration in . Therefore, by projecting on the Slepian basis , the projected vector will have a value very close to of And achieve Alternatively, the method is known from the previous discussion and , so for the Slepian basis, can be determined as in equation (8).

[0332]

[0333] … (8)

[0334] In any basis, The estimate of For the Slepian basis, each of the bases has And therefore The estimate also has .

[0335] CS and timing offset compensation.

[0336] For simplicity, assume The timing offset compensation and assignment of the CS of the exponential complex sequence should be such that the DTFT of all UEs should be non-overlapping and This can be dispatched in one of three ways.

[0337] ● and CS such that the exponential complex sequence of UE is , ,etc.

[0338] ● Without timing offset compensation and CS, the exponential complex sequence of all UEs is , ,wait.

[0339] ● Without timing offset compensation and CS, the exponential complex sequence of all UEs is , , etc. Here, a can be an integer or a fraction or both. For fractions, it is extracted from the columns of the oversampled DFT matrix.

[0340] here, Can be the smallest integer greater than or equal to half the perceived bandwidth.

[0341] Fig.39 and Fig.40 is a diagram illustrating a Slepian sequence-time half-bandwidth product according to an embodiment.

[0342] refer to Fig.39 and Fig.40, 13 sinusoid or exponential waves are generated and added together to produce a sequence of length N. The sinusoids are selected from the range - to Therefore, it is expected that R s =2A.

[0343] Fig.39 and Fig.40 It is shown that if a signal of N samples is band-limited between x and -x, then the signal lies in the subspace spanned by 2NX Slepian bases.

[0344] Fig.41 and Fig.42 is a diagram showing R according to the embodiment F and R S .

[0345] refer to Fig.41 and Fig.42 , the parameters used are The figure shows how the SRS channel in the frequency domain can be modeled with much fewer Slepian basis coefficients than DFT basis coefficients.

[0346] So far, the UE processes and presents SRS with exponential complex sequences and ZC sequences spanning only SRS subcarriers in any OFDM symbol and repeating across SRS OFDM symbols. The above embodiments can also be applied to OTFS transmitters and receivers when SRS subcarriers use complex exponential sequences in both time and frequency.

[0347] Fig.43 A 2D pilot according to an embodiment is shown.

[0348] refer to Fig.43 , this method assumes a rectangular area of ​​the pilot, which can be derived from any configuration (Scheme 1 / Scheme 2 / Scheme 3).

[0349] Let the rectangular time-frequency grid of the pilot be (M frequency values ​​and N time symbols).

[0350] This method assumes that N U UEs use the same time-frequency resources. The i-th UE sends a pilot signal S through a rectangular time-frequency grid. i (the i-th UE pilot matrix), as shown in equation (9).

[0351]

[0352] … (9)

[0353] In equation (9), yes The a-th column vector of the IFFT matrix, The IFFT matrix Elements by Given, where is the Hadamard product or element-wise multiplication of matrices, and is a 2D sequence in the time and frequency domains, and as a special case, can be an all-unity sequence. is called the i-th Z-user pilot matrix and It is called the i-th R-user pilot matrix.

[0354] Throughout this disclosure, a UE may refer to a port, and a port may also refer to a UE.

[0355] This arrangement of 2D pilots can also be applied to the OTFS transmitter.

[0356] 2D Channel : The 2D channel is given by equation (10).

[0357]

[0358] … (10)

[0359] In equation (10), is a 2D basis matrix, and there are MN such matrices, and Mtd represents the choice of basis (and will be discarded later). The choice of basis can be Slepian, polynomial, DCT, DFT, oversampled DFT, Karhunen-Loeve, etc., and x is the basis coefficient of the i-th user associated with the corresponding basis matrix.

[0360] The i-th UE channel matrix can be approximated as shown in equation (11).

[0361]

[0362] … (11)

[0363] In equation (11), F and T are subsets of {0,...,M-1} and {0,...,N-1}, respectively.

[0364] Using vectorized operations on matrices, the i-th channel vector can be determined using equation (12).

[0365]

[0366] … (12)

[0367] In equation (12), the basis vectors are .

[0368] Define the vectorized basis matrix and ,in, , . The total number of elements in F and T is R. The dimension is The received signal matrix on the rectangular time-frequency grid is shown in equation (13).

[0369] ... (13)

[0371] Using vectorized operations on matrices, the method forms a vector of received values ​​on the pilot subcarriers as shown in equation (14).

[0372]

[0373] … (14)

[0374] In equation (14), A is the full user vectorization basis matrix, is the full user basis coefficient vector, and is the diagonalized and vectorized version of the i-th UE pilot matrix. A diagonal matrix X with column vectors x along the main diagonal is denoted by X=diag(x). The dimension of A is .here, is the i-th user basis coefficient vector, and is the full user basis coefficient vector, as shown in equation (15).

[0375]

[0376] ... (15)

[0378] definition As each of its elements is The inverse matrix of the corresponding element. It will be referred to as the i-th UEzbar pilot matrix.

[0379] If all UE / ports have the same sequence , then this method can be used To represent this sequence, and use To represent the corresponding matrix. In this case, define and .

[0380] Using vectorized operations on matrices, this method forms the received vector into .also, .

[0381] 2D Receiver

[0382] here, .

[0383] Will Estimated .

[0384] If the Z-user pilot matrix is ​​the same for all UEs, then and .according to , is extracted and can be obtained The estimate is .

[0385] Complexity

[0386] a) Consider 12 SRS subcarriers in frequency and 12 SRS OFDM symbols in time slot. Total 16 UEs. Four CS in time domain and four CS in frequency domain. Assume Same for all UEs / ports.

[0387] b) Case 1: In both time and frequency domains, CS = 0, 3, 6, 9. For all 16 UEs, , so that

[0388] c) Case 2: In both time and frequency domains, CS = 1, 4, 7, 10. For all 16 UEs, , so that

[0389] d) Order and is the A matrix for Case 1 and Case 2 above.

[0390] e) This method can see and are the same and can be precomputed and stored, and furthermore do not depend on Z.

[0391] f) ,in, Along the diagonal line The diagonal matrix of .

[0392] g) can be precomputed and can be easily calculated.

[0393] h) Therefore, new algorithms can be easily implemented. Similar analysis applies to . Basis Matrix Can be from any basis like Slepian, Polynomial, DFT, Oversampled DFT, DCT, Karhunen-Loeve or any other basis.

[0394] Timing and frequency offset compensation

[0395] If there is a timing offset (which may be different for different UEs, but is the same for all ports), if a UE is involved, the UE uses a value which is either the maximum or an intermediate value for all possible UEs). Therefore, the kth RE (resource element) will thus experience a phase change of ,in, is the subcarrier spacing. The compensated timing offset vector It is constructed as shown in equation (16).

[0396] .

[0397] … (16)

[0398] If there is a frequency offset (in Hz) (which may be different for different UEs, but is the same for all ports), if a UE is involved, the UE uses a value that is either a maximum or an intermediate value for all possible UEs). Therefore, all REs in the nth OFDM symbol will thus experience a phase change of ,in, is the OFDM symbol duration in seconds including the CP. The compensated frequency offset vector It is constructed as shown in equation (17).

[0399]

[0400] … (17)

[0401] The received signal vector Y is pre-compensated as Y=diag( diag( , as a first step before further processing in a 2D-SRS or OTFS receiver.

[0402] CS and exponential complex sequences

[0403] The pilot matrix of the i-th R user is given as .here, are exponential complex sequences in the frequency and time domains, with CS a and b, respectively. Let the channel in frequency For any a (time) and i (user) with of perceived bandwidth and is limited by bandwidth and Similarly, let the channel in time For any b (frequency) and i (user) with of perceived bandwidth and is limited by bandwidth and between.

[0404] Furthermore, when discussing in the context of the frequency domain, let , because there are M pilots per OFDM symbol in the frequency domain, and in the context of the time domain, let , because there are N pilots per subcarrier in the time domain. Here is called the mg vector and g is the index into the mg vector.

[0405] CS and frequency offset compensation.

[0406] For exponential complex sequences and frequency offset compensation in the time domain:

[0407] a) and CS make the exponential complex sequence of all UEs in the time domain , ,wait.

[0408] b) Without frequency offset compensation and CS, the exponential complex sequence of all UEs in the time domain is , ,wait.

[0409] c) There is no frequency offset compensation and CS, so that the exponential complex sequence of all UEs in the time domain is , , etc. Here, a can be an integer or a fraction or both. For fractions, it is extracted from the columns of the oversampled DFT matrix.

[0410] d) In one embodiment, In a)-c) above, y may be the smallest integer greater than or equal to half of the perceptual bandwidth of the channel in the time domain.

[0411] CS and timing offset compensation: For exponential complex sequences and timing offset compensation in the frequency domain:

[0412] a) and CS make the exponential complex sequence of all UEs in the frequency domain be , ,wait.

[0413] b) Without timing offset compensation and CS, the exponential complex sequence of all UEs in the frequency domain is , ,wait.

[0414] c) There is no timing offset compensation and CS, so the exponential complex sequence of all UEs in the frequency domain is , , etc. Here, a can be an integer or a fraction or both. For fractions, it is extracted from the columns of the oversampled DFT matrix.

[0415] d) In one embodiment, In the above a)-c) it can be the smallest integer greater than or equal to half of the perceptual bandwidth of the channel in the frequency domain.

[0416] This method can be used to extend to any Rx of any channel, not just SRS receiver. This method can also be used for PDSCH receiver / PUSCH receiver.

[0417] Fig.44 A BS according to an embodiment is shown.

[0418] refer to Fig.44 , the BS includes a transceiver 4410, a memory 4420, and a processor 4430. The transceiver 4410, the memory 4420, and the processor 4430 of the BS may operate according to the communication method of the above-mentioned BS. However, the components of the BS are not limited thereto. For example, the BS may include more or less components than the above-mentioned components. In addition, the processor 4430, the transceiver 4410, and the memory 4420 may be implemented as a single chip. The processor 4430 may include at least one processor.

[0419] The transceiver 4410 collectively refers to a receiver and a transmitter, and can send / receive signals to / from a terminal (or UE) or a network entity. The signals sent to or received from a terminal or a network entity may include control information and data. The transceiver 4410 may include a radio frequency (RF) transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for amplifying low noise and down-converting the frequency of a received signal. However, this is only an example of the transceiver 4410, and the components of the transceiver 4410 are not limited to the RF transmitter and the RF receiver.

[0420] The transceiver 4410 may receive a signal through a wireless channel and output a signal to the processor 4430 , and transmit a signal output from the processor 4430 through a wireless channel.

[0421] The memory 4420 may store programs and data required for the operation of the BS. The memory 4420 may store control information or data included in a signal obtained by the BS. The memory 4420 may be a storage medium such as a ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media.

[0422] The processor 4430 may control a series of processes so that the BS operates as described above. For example, the transceiver 4410 may receive a data signal including a control signal transmitted by a terminal, and the processor 4430 may determine a result of receiving the control signal and the data signal transmitted by the terminal.

[0423] Fig.45 A UE according to an embodiment is shown.

[0424] refer to Fig.45 , the UE includes a transceiver 4510, a memory 4520, and a processor 4530. The transceiver 4510, the memory 4520, and the processor 4530 of the UE may operate according to the communication method of the UE described above. However, the components of the UE are not limited thereto. For example, the UE may include more or fewer components than the above components. In addition, the processor 4530, the transceiver 4510, and the memory 4520 may be implemented as a single chip. The processor 4530 may include at least one processor.

[0425] The transceiver 4510 collectively refers to a receiver and a transmitter, and can send / receive signals to / from a BS or a network entity. The signals sent to or received from the BS or a network entity may include control information and data. The transceiver 4510 may include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for amplifying the low noise and down-converting the frequency of the received signal. However, this is only an example of the transceiver 4510, and the components of the transceiver 4510 are not limited to the RF transmitter and the RF receiver.

[0426] The transceiver 4510 may receive a signal through a wireless channel and output a signal to the processor 4530 , and transmit a signal output from the processor 4530 through a wireless channel.

[0427] The memory 4520 may store programs and data required for the operation of the UE. The memory 4520 may store control information or data included in a signal obtained by the UE. The memory 4520 may be a storage medium such as a ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media.

[0428] The processor 4530 may control a series of processes so that the UE operates as described above. For example, the transceiver 4510 may receive a data signal including a control signal sent by a BS or a network entity, and the processor 4530 may determine a result of receiving the control signal and the data signal sent by the BS or the network entity.

[0429] Those skilled in the art will appreciate that the various illustrative logic blocks, modules, circuits and steps described in the present application can be implemented as hardware, software or a combination of the two. In order to clearly illustrate this interchangeability between hardware and software, various illustrative components, blocks, modules, circuits and steps are generally described above in the form of their function sets. Whether such function sets are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. Technicians can implement the described function sets in different ways for each specific application, but such design decisions should not be interpreted as causing departure from the scope of the present application.

[0430] In the above-mentioned embodiments of the present disclosure, all operations and messages may be selectively performed or omitted. In addition, the operations in each embodiment do not need to be performed sequentially, and the order of operations may be different. Messages do not need to be sent in order, and the order in which messages are sent may be changed. The transmission of each operation and each message may be performed independently.

[0431] Although the drawings show different examples of UEs, various changes may be made to the drawings. For example, the UE may include any number of each component in any suitable arrangement. In general, the drawings do not limit the scope of the present disclosure to any particular configuration. In addition, although the drawings show operating environments in which various UE features disclosed in this patent document may be used, these features may be used in any other suitable system.

[0432] The various illustrative logic blocks, modules, and circuits described in this application may be implemented or executed by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in cooperation with a DSP core, or any other such configuration.

[0433] The steps of the method or algorithm described in this application can be directly embodied in hardware, in a software module executed by a processor, or in a combination thereof. The software module can reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, or any other form of storage medium known in the art. The storage medium is coupled to the processor so that the processor can read information from the storage medium / write information to the storage medium. Alternatively, the storage medium can be integrated into the processor. The processor and the storage medium can reside in an ASIC. The ASIC can reside in a terminal. Alternatively, the processor and the storage medium can reside in a terminal as discrete components.

[0434] In one or more designs, the functions may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, each function may be stored on or transmitted through a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, the latter including any media that facilitates the transfer of computer programs from one location to another. Storage media may be any available media that can be accessed by a general or special purpose computer.

[0435] While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

Claims

1. A method performed by a base station (BS) in a wireless network, the method comprising: Sending, to a user equipment (UE), configuration information for resource allocation to at least one port of the UE; and Based on the resource allocation configuration information, receive a sounding reference signal (SRS) from the UE, wherein the resource allocation comprises at least one of cyclic shift (CS) allocation or comb shift allocation, and Therein, the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

2. The method according to claim 1, wherein: The configuration information for sending resource allocation includes: distributing the set of allowable CS values ​​into a first subset of CS values ​​and a second subset of CS values, wherein the first subset of CS values ​​is provided as first consecutive CS values ​​and the second subset of CS values ​​is provided as second consecutive CS values; assigning a CS from the first subset and the second subset of CS values ​​to the at least one port of the UE; and causing the allocated CS value to jump to the at least one port of the UE within the first subset or the second subset, The hopping is performed across Orthogonal Frequency Division Multiplexing (OFDM) symbols.

3. The method according to claim 2, wherein: A guard band of unused CS values ​​is created between the first subset and the second subset of CS values.

4. The method according to claim 2, wherein: Assigning a CS from the first subset and the second subset of CS values ​​is performed explicitly for all ports of the UE.

5. A method performed by a user equipment (UE) in a wireless network, the method comprising: receiving, from a base station (BS), configuration information for resource allocation to at least one port of a UE; and Based on the resource allocation configuration information, a sounding reference signal (SRS) is sent to the BS. wherein the resource allocation comprises at least one of cyclic shift (CS) allocation or comb shift allocation, and Therein, the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

6. The method according to claim 5, in, The set of allowable CS values ​​is distributed among a first subset of CS values ​​and a second subset of CS values, wherein the first subset of CS values ​​is provided as first consecutive CS values ​​and the second subset of CS values ​​is provided as second consecutive CS values, wherein a CS from the first subset and the second subset of CS values ​​is assigned to the at least one port of the UE, The allocated CS value jumps to the at least one port of the UE within the first subset or the second subset, and The hopping is performed across Orthogonal Frequency Division Multiplexing (OFDM) symbols.

7. The method according to claim 6, wherein: A guard band of unused CS values ​​is created between the first subset and the second subset of CS values.

8. The method according to claim 6, wherein: CS values ​​from the first subset and the second subset of CS values ​​are explicitly assigned to all ports of the UE.

9. A base station (BS) in a wireless communication system, the BS comprising: Transceiver; and a processor coupled to the transceiver and configured to: Sending to a user equipment (UE) configuration information for resource allocation to at least one port of the UE, and Based on the resource allocation configuration information, receive a sounding reference signal (SRS) from the UE, wherein the resource allocation comprises at least one of cyclic shift (CS) allocation or comb shift allocation, and Therein, the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

10. The BS according to claim 9, wherein the processor is further configured to: The set of permissible CS values ​​is distributed among a first subset of CS values ​​and a second subset of CS values, wherein, The first subset of CS values ​​is provided as first consecutive CS values ​​and the second subset of CS values ​​is provided as second consecutive CS values, assigning a CS from the first subset and the second subset of CS values ​​to the at least one port of the UE, and causing the allocated CS value to jump to the at least one port of the UE within the first subset or the second subset, The hopping is performed across Orthogonal Frequency Division Multiplexing (OFDM) symbols.

11. The BS according to claim 10, wherein: A guard band of unused CS values ​​is created between the first subset and the second subset of CS values.

12. The BS according to claim 10, wherein: CS values ​​from the first subset and the second subset of CS values ​​are explicitly assigned to all ports of the UE.

13. A user equipment (UE) in a wireless communication system, the UE comprising: Transceiver; and a processor coupled to the transceiver and configured to: receiving configuration information of resource allocation for at least one port of the UE from a base station (BS), and Based on the resource allocation configuration information, a sounding reference signal (SRS) is sent to the BS. wherein the resource allocation comprises at least one of cyclic shift (CS) allocation or comb shift allocation, and Therein, the resource allocation is based on values ​​from one or more subsets of a set of allowable CS values ​​or allowable comb shift values.

14. The UE according to claim 13, wherein: The set of allowable CS values ​​is distributed among a first subset of CS values ​​and a second subset of CS values, wherein the first subset of CS values ​​is provided as first consecutive CS values ​​and the second subset of CS values ​​is provided as second consecutive CS values, wherein a CS from the first subset and the second subset of CS values ​​is assigned to the at least one port of the UE, The allocated CS value jumps to the at least one port of the UE within the first subset or the second subset, and The hopping is performed across Orthogonal Frequency Division Multiplexing (OFDM) symbols.

15. The UE according to claim 14, wherein: A guard band of unused CS values ​​is created between the first subset and the second subset of CS values.

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