OFDM-based method and apparatus for spreading and transmitting compressed data

Abstract

The disclosure relates to a communication technology and system that combines Internet of Things technology with a 5G communication system to support a higher data transmission rate than a 4G system. The disclosure can be applied to intelligent services (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail businesses, security and safety-related services, etc.) based on 5G communication technology and Internet of Things-related technology. A method of a transmitter of a communication system according to the disclosure is characterized by transmitting configuration information for signal transmission to a receiver, checking resources for signal transmission, transmitting scheduling information indicating the resources to the receiver, converting a transmission signal into a compressed signal so as to correspond to the configuration information, spreading the compressed signal to a plurality of dimensions, mapping a part of the spread compressed signal to resources corresponding to the scheduling information, converting the spread compressed signal to generate an orthogonal frequency division multiplexing (OFDM) signal, and transmitting the generated OFDM signal to the receiver.

Description

Technical Field

[0001] This invention relates to a technique for processing signals in a wireless communication system, and more specifically, to a method and apparatus for transmitting data to transmit signals in an orthogonal frequency division multiplexing (OFDM) based system. Background Technology

[0002] To meet the demands for wireless data traffic since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "beyond 4G network" communication systems or "post-LTE" systems. 5G communication systems are considered to be implemented in ultra-high frequency (mmWave) bands (e.g., the 60GHz band). To reduce radio wave propagation loss and increase transmission distance in the mmWave band, beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large-scale antenna technologies have been discussed in 5G communication systems. Furthermore, system network improvements are being developed in 5G communication systems based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multipoint (CoMP), and receiver interference cancellation. In 5G systems, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) as advanced coding and modulation (ACM), as well as filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies, have also been developed.

[0003] The internet, a human-centric network of connections where humans generate and consume information, is now evolving into the Internet of Things (IoT), in which distributed entities (such as transactions) exchange and process information without human intervention. The Internet of Everything (IoE) has emerged by combining IoT technology with big data processing technology through connections to cloud servers. As the realization of the IoT demands technological elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology, sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) have recently been researched. Such an IoT environment can provide intelligent internet technology (IT) services, creating new value for human life by collecting and analyzing data generated between connected things. Through the integration and combination of existing information technology (IT) with various industrial applications, the IoT can be applied to a wide range of fields, including smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart appliances, and advanced medical services.

[0004] According to this, various attempts have been made to apply the 5G communication system to the Internet of Things network. For example, technologies such as sensor network, machine type communication (MTC), and machine-to-machine (M2M) communication can be implemented through beamforming, MIMO, and array antennas. Application of a cloud radio access network (cloud RAN), which is the above-described big data processing technology, can also be considered as an example of convergence of the 5G technology with the Internet of Things technology.

[0005] In addition, for future communication systems, methods of transmitting signals in an ultrahigh frequency band are being researched to achieve a higher data transmission rate. SUMMARY

[0006] TECHNICAL PROBLEM

[0007] One aspect of the disclosure is to provide a method and apparatus for transmitting data robust to noise in a system in which internal noise of a transmitter and a receiver is large, such as noise in a frequency band from an ultrahigh frequency to a terahertz (THz) wave.

[0008] SOLUTION TO PROBLEM

[0009] A method of solving a problem by a transmitter in a wireless communication system according to the disclosure includes transmitting configuration information for transmitting a signal to a receiver, converting the transmitted signal into a compressed signal according to the configuration information, spreading the compressed signal to a plurality of dimensions, mapping some of the spread compressed signal to a resource corresponding to scheduling information, and multiplexing the signal with other signals to generate an OFDM signal and transmitting the generated OFDM signal.

[0010] The method can further include transmitting Doppler spread, channel spread, or profile information corresponding thereto through channel information feedback from the receiver, or causing the transmitter to recognize the information.

[0011] A method of a receiver in a wireless communication system includes receiving configuration information for receiving a signal from a transmitter, receiving scheduling information for receiving a signal from the transmitter, reconstructing the received signal based on the configuration information and the scheduling information, and decompressing the reconstructed signal to obtain transmission information.

[0012] A transmitter in a wireless communication system includes a transmitter, and a controller connected to the transceiver and configured to perform control to transmit configuration information for transmitting a signal to a receiver, generate a transmission signal based on the configuration information, transmit control information including resource allocation information indicating a signal allocation resource to the receiver, generate a transmission signal obtained by applying multi-dimensional spreading to a modulation signal to be transmitted, and transmit the generated transmission signal to the receiver in the signal allocation resource.

[0013] A receiver in a wireless communication system includes a transmitter; and a controller connected to the transceiver and configured to receive configuration information for transmitting a signal from the transmitter, store samples for signal processing for generating the transmitted signal based on the configuration information, receive control information including resource allocation information indicating a signal allocation resource from the transmitter, receive a received signal in the signal allocation resource from the transmitter, and reconstruct compressed data information in the received signal.

[0014] Advantages of the Invention

[0015] According to embodiments of the present disclosure, there is a significant signal reconstruction effect in a system having a series of internal noise, and in particular, by compressing and expanding transmission data and transmitting it to multiple dimensions, the signal is effectively reconstructed by transmitting only some of the expanded signals. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The basic structure of the time-frequency domain is shown, which is a wireless resource area in which data or control channels of a 5G system are transmitted.

[0017] Figure 2 The frame, subframe, and slot structure in the 5G system is shown.

[0018] Figure 3 An example of a resource grid in the d-D region proposed in the present disclosure is shown.

[0019] Figure 4 An example of expansion to the t-f domain proposed in the present disclosure is shown.

[0020] Figure 5 An example of allocation of t-f domain resources proposed in the present disclosure is shown.

[0021] Figure 6 The transmission operation of the transmitter proposed in the present disclosure is shown.

[0022] Figure 7 The reception operation of the receiver proposed in the present disclosure is shown.

[0023] Figure 8 The performance according to the embodiments proposed in the present disclosure is shown.

[0024] Figure 9 Another diagram showing the performance according to the example proposed in the present disclosure is shown.

[0025] Figure 10 Another diagram showing the performance according to the example proposed in the present disclosure is shown.

[0026] Figure 11 Another diagram showing the performance according to the example proposed in the present disclosure is shown.

[0027] Figure 12 FIG. 3 is another diagram illustrating performance according to examples presented in the disclosure.

[0028] Figure 13 FIG. 4 is a block diagram illustrating a structure of a transmitter according to an embodiment of the disclosure.

[0029] Figure 14 FIG. 5 is a block diagram illustrating a structure of a receiver according to an embodiment of the disclosure. DETAILED DESCRIPTION

[0030] Embodiments of the disclosure will be described below in detail with reference to the accompanying drawings.

[0031] In describing embodiments, descriptions related to technical contents known in the art to which the disclosure pertains and not directly related to the disclosure will be omitted. Such omission of unnecessary descriptions is to prevent obscuring the main idea of the disclosure and to more clearly convey the main idea.

[0032] For the same reason, in the drawings, some elements can be exaggerated, omitted, or schematically illustrated. Also, the size of each element does not completely reflect the actual size. In the drawings, the same or corresponding elements have the same reference numerals.

[0033] The advantages and features of the disclosure and the means for achieving them will be apparent by referring to the embodiments described below in detail in connection with the accompanying drawings. However, the disclosure is not limited to the embodiments described below, but can be implemented in various different forms. The following embodiments are provided merely to completely disclose the disclosure and to inform those skilled in the art of the scope of the disclosure, and the disclosure is limited only by the scope of the claims. Throughout the specification, the same or similar reference numerals denote the same or similar elements.

[0034] It should be understood that each of the blocks of the flowchart illustrations, and combinations of blocks in the flowchart illustrations, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart block or blocks. These computer program instructions can also be stored in a computer-usable or computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer- usable or computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks.

[0035] Furthermore, each block of the flowchart illustrations can represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions shown in the blocks can occur out of the order depicted. For example, two blocks shown in succession can in fact be executed substantially concurrently or the blocks can sometimes be executed in the reverse order, depending upon the functionality involved.

[0036] As used in the embodiments of the present disclosure, a "unit" refers to a software element or a hardware element that performs a predetermined function, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC). However, the meaning of "unit" is not limited to software or hardware. A "unit" can be constructed as a storage medium that stores software elements or as a processor that executes software elements. Thus, "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, attributes, procedures, sub-routines, program codes, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays, and parameters. Elements and functions provided by a "unit" can be either combined with fewer elements and "units" or divided into more elements and "units". In addition, elements and "units" can be implemented to reproduce one or more CPUs within a device or a secure multimedia card. Furthermore, according to some embodiments, "unit" can include one or more processors.

[0037] The working principle of the technical idea of the present disclosure will be described in detail below with reference to the accompanying drawings. In the following description of the technical idea of the present disclosure, a detailed description of known functions or configurations incorporated herein will be omitted when it is determined that such a description can unnecessarily obscure the subject matter of the present disclosure. The terms to be described below are terms defined in consideration of the functions in the present disclosure, and can be different according to users, user intentions, or customs. Therefore, the definition of the terms should be based on the content of the entire specification.

[0038] In the following description, a base station is an entity that allocates resources to a terminal, and can be at least one of a gNode B, an eNode B, and a base station (BS), a radio access unit, a base station controller, and a node on a network. The terminal can include a user equipment (UE), a mobile station (MS), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. Of course, examples of the base station and the terminal are not limited thereto. In the following description of the present disclosure, a technology in which a terminal in a wireless communication system receives broadcast information from a base station will be described. The present disclosure relates to a communication technology for converging a 5th-Generation (5G) communication system for a 5th-Generation (5G) communication system designed to support higher data transmission rates than a 4th-Generation (4G) system, and a system therefor. The present disclosure is applicable to intelligent services (e.g., smart home, smart building, smart city, smart car or connected car, health care, digital education, retail industry, security and safety-related services, etc.) based on 5G communication technology and IoT-related technology.

[0039] In the following description, for convenience, terms related to broadcast information, terms related to control information, terms related to communication coverage, terms related to state change (e.g., event), terms related to network entity, terms related to message, terms related to device elements, etc. are exemplarily used. Therefore, the present disclosure is not limited by the terms used below, and other terms having equivalent technical meanings can be used.

[0040] In the following description, for convenience of description, some terms and names defined in the 3rd Generation Partnership Project (3GPP) LTE or NR standards can be used. However, the present disclosure is not limited by these terms and names, and can be equally applied to systems conforming to other standards.

[0041] Wireless communication systems are evolving into broadband wireless communication systems using communication standards that provide high-speed and high-quality packet data services as well as typical voice-based services, such as High Speed Packet Access (HSPA) of 3GPP, LTE {Long Term Evolution or Evolved Universal Terrestrial Radio Access (E-UTRA)}, LTE-Advanced (LTE-A), LTE-Pro, High Rate Packet Data (HRPD) of 3GPP2, High Speed Packet Transmission (HSPA) of 3GPP3, Ultra Mobile Broadband (UMB), IEEE 1102.16e, etc.

[0042] As a typical example of a broadband wireless communication system, an LTE system employs an Orthogonal Frequency Division Multiplexing (OFDM) scheme in a downlink (DL) and a Single Carrier Frequency Division Multiple Access (SC-FDMA) scheme in an uplink (UL). The uplink indicates a radio link through which a user equipment (UE) {or a mobile station (MS)} transmits data or a control signal to a base station (BS) (eNode B), and the downlink indicates a radio link through which the BS transmits data or a signal to the UE. The above-described multiple access scheme separates data and control information of respective users by allocating and operating time-frequency resources for transmitting data or control information of each user so as to avoid overlapping each other, i.e., establishing orthogonality.

[0043] Since a 5G communication system, which is a post-LTE communication system, must freely reflect various requirements of users, service providers, etc., services satisfying various requirements must be supported. Services considered in the 5G communication system include enhanced mobile broadband (eMBB) communication, massive machine type communication (mMTC), ultra reliability low latency communication (URLLC), etc.

[0044] According to some embodiments, eMBB aims to provide a higher data rate than a data rate supported by existing LTE, LTE-a, or LTE Pro. For example, in the 5G communication system, eMBB must provide a peak data rate of 20 Gbps in a downlink and a peak data rate of 10 Gbps in an uplink for a single base station. In addition, the 5G communication system must provide an increased user-perceived data rate as well as a maximum data rate to a UE. In order to meet these requirements, transmission / reception techniques including further enhanced Multiple Input Multiple Output (MIMO) transmission techniques need to be improved. In addition, the data rate required for the 5G communication system can be obtained using a bandwidth greater than 20 MHz in a frequency band of 3 to 6 GHz or more than 6 GHz, instead of transmitting a signal using a transmission bandwidth of up to 20 MHz in a 2 GHz frequency band used in LTE.

[0045] In addition, mMTC is considering support for application services such as Internet of Things (IoT) in a 5G communication system. In order to efficiently provide Internet of Things, mMTC has requirements such as support for connection of a large number of UEs in a cell, enhancement of coverage of a UE, improvement of battery time, reduction of cost of a UE, etc. Since Internet of Things provides a communication function while providing various sensors and various devices, it must support a large number of UEs (e.g., 1,000,000 UEs / km2) in a cell. In addition, a UE supporting mMTC can need a wider coverage range than other services provided by a 5G communication system because the UE can be located in a shadow area such as a basement of a building, which is not covered by a cell due to the nature of the service. A UE supporting mMTC must be configured to be inexpensive, and can need a very long battery life because it is difficult to frequently replace the battery of the UE.

[0046] Finally, URLLC is a kind of mission-critical wireless communication service based on a cell, which can be used for remote control of robots or machines, industrial automation, unmanned aerial vehicles, telemedicine, emergency alerts, etc. Therefore, URLLC must provide ultra-low latency and ultra-high reliability communication. For example, a service supporting URLLC must satisfy an air interface latency of less than 0.5 ms, and also requires a data packet error rate of 10-5 or less. Therefore, for a service supporting URLLC, a 5G system must provide a shorter transmission time interval (TTI) than other services, and also needs a design that allocates a large amount of resources in a frequency band to secure reliability of a communication link. However, the above-described mMTC, URLLC, and eMBB are only examples of different types of services, and the service types to which the present disclosure is applicable are not limited to the above-described examples.

[0047] The above-described services considered in the 5G communication system must be integrated with each other in order to be provided based on one framework. That is, in order for efficient resource management and control, each service is preferably integrated into a single system and controlled and transmitted in the integrated single system, rather than being operated separately.

[0048] Hereinafter, a framework structure of a 5G system will be described in more detail with reference to the accompanying drawings.

[0049] Figure 1 A basic structure of a time-frequency domain, which is a wireless resource area in which data or a control channel of a 5G system is transmitted, is illustrated.

[0050] Reference Figure 1 In Figure 1 , the horizontal axis represents a time domain, and the vertical axis represents a frequency domain. A basic unit of a resource in the time and frequency domains is a resource element (RE) 100, and can be defined as one OFDM symbol 110 in the time axis and one subcarrier 120 in the frequency axis. In the frequency domain, A resource block (RB) 130 can be constructed of 12 consecutive REs.

[0051] Figure 2 A frame, a subframe, and a slot structure in a 5G system are shown.

[0052] Referring to Figure 2 , an example of a structure of a frame 200, a subframe 210, and a slot 220 is shown. One frame 200 can be defined as 10 ms. One subframe 210 can be defined as 1 ms, and one frame 200 can include a total of 10 subframes 210. One slot 220 or 230 can be defined as 14 OFDM symbols (i.e., the number of symbols per slot ). One subframe 210 can include one or more slots 220 or 230, and the number of slots 220 and 230 per subframe 210 can vary according to a configuration value μ 240 or 250 of a subcarrier spacing.

[0053] In an example of Figure 2 , cases of subcarrier spacing setting values μ = 0 240 and μ = 1 250 are shown. In the case of μ = 0 240, one subframe 210 can consist of one slot 2220. In the case of μ = 1 250, one subframe 210 can consist of two slots 230. That is, the number of slots per subframe can be different according to the configuration value μ of the subcarrier spacing, and thus, the number of slots per frame can be different. The and per subcarrier spacing configuration μ can be defined as shown in [Table 1] below. [Table 1]

[0054] [Table 1]

[0055]

[0056] ​In NR, one component carrier (CC) or serving cell can include up to 250 RBs. Thus, when a UE always receives the entire serving cell bandwidth as in LTE, the power consumption of the UE can be very large, and thus, to address this issue, a BS can configure one or more bandwidth parts (BWPs) in the UE and support the UE to change the reception area within the cell. In NR, the BS can configure an "initial BWP" through a master information block (MIB), which is the bandwidth of CORESET #0 (or common search space (CSS)) in the UE. Thereafter, the BS can configure the first BWP of the UE through radio resource control (RRC) signaling and inform one or more pieces of BWP configuration information that can be indicated through downlink control information (DCI) in the future. Thus, the BS can indicate which frequency band the UE will use through the BWP ID informed through the DCI. If the UE does not receive the DCI in the currently allocated BWP for a specific time or longer, the UE can return to the default BWP and attempt to receive the DCI.

[0057] Subsequently, downlink control information (DCI) in a 5G system is described in detail.

[0058] In a 5G system, scheduling information of uplink data (or a physical uplink data channel (physical uplink shared channel (PUSCH))) or downlink data (or a physical downlink data channel (physical downlink shared channel (PDSCH))) is transmitted from a BS to a UE through DCI. The UE can monitor fallback DCI formats and non-fallback DCI formats of the PUSCH or the PDSCH. The fallback DCI format can include a fixed field that is predefined between the BS and the UE, and the non-fallback DCI format can include a configurable field.

[0059] The DCI can be transmitted via a physical downlink control channel (PDCCH) through channel coding and modulation processing. A cyclic redundancy check (CRC) is added to a DCI message payload and is scrambled with a radio network temporary identifier (RNTI) corresponding to the identity of the terminal. Different RNTIs are used according to the purpose of the DCI message, for example, UE-specific data transmission, a power control command, or a random access response. That is, the RNTI is not explicitly transmitted but is included in the CRC calculation process to be transmitted. If a DCI message transmitted through the PDCCH is received, the UE can identify the CRC through the allocated RNTI, and when it is determined that the CRC is correct based on the CRC identification result, the UE can identify that the corresponding message has been transmitted to the UE.

[0060] The DCI format 1_0 can be used for fallback DCI for scheduling the PDSCH, in which case the CRC can be scrambled by the C-RNTI. The DCI format 1_0 with the CRC scrambled by the C-RNTI can include, for example, the information in the following [Table 2].

[0061] [Table 2]

[0062]

[0063] The DCI format 1_1 can be used for non-fallback DCI for scheduling the PDSCH, in which case the CRC can be scrambled by the C-RNTI. The DCI format 1_1 with the CRC scrambled by the C-RNTI can include, for example, the information in the following [Table 3].

[0064] [Table 3]

[0065]

[0066]

[0067] In the 5G system, in the process of transmitting an OFDM signal, a coded symbol (or coded bit) is converted into a modulation symbol by modulation, and M modulation symbols are collected and converted into a parallel signal by a serial-to-parallel (S / P) converter. The M converted symbols are mapped to desired subcarrier positions, and then converted into an OFDM signal by applying an inverse fast Fourier transform (IFFT). The converted time samples are converted into serial time samples by a parallel-to-serial (P / S) conversion, a cyclic prefix is concatenated thereto, and then a signal is generated by a digital-to-analog converter (DAC) and a radio frequency (RF). The OFDM signal can be transmitted in a frequency band from a low band to a high band. However, when a high band is used, very high power consumption occurs due to a high sampling rate, a wide bandwidth, and low hardware efficiency, so a receiver cannot always remain in an active state and can only wake up when data is received. When the receiver wakes up for a very short time interval to receive and process data while minimizing performance degradation, there should be sufficient additional information before the signal processing of the receiver. In a conventional cellular communication system, some resources (usually 20% or more) can be used to transmit and receive a pilot signal in order to support acquisition of synchronization and channel information required for demodulation of time, frequency, and / or Doppler.

[0068] A bottleneck phenomenon occurring when a signal is processed for a short time in a high band is described below. Internal noise generated by an RF device changes a phase, which is called phase noise, and causes a serious degradation in performance of a receiver. That is, when a frequency band used for transmitting and receiving a signal is significantly high, it is more difficult to achieve the same level of reception accuracy with the same amount of pilot signal resources. For this reason, a method of minimizing the required overhead and obtaining data channel information required for a signal damaged by noise is needed.

[0069] Hereinafter, "d" denotes a delay domain of a channel, "D" denotes a Doppler domain of a channel, "t" denotes a time domain of a channel, and "f" denotes a frequency domain of a channel. "d-D" denotes a two-dimensional domain of delay and Doppler, and "t-f" denotes a two-dimensional domain of time and frequency.

[0070] According to the method proposed in the disclosure, the transmitter applies symbol mapping in a d-D resource grid (i.e., a two-dimensional grid of N d x N D ), and transmits actual data packets using a t-f resource grid (i.e., a two-dimensional grid of N F x N T ), such as an OFDM-based multicarrier signal. In order to obtain the second-order statistics of the channel between the transmitter and the receiver, i.e., the information about the Doppler spread L D (in symbol units) and the delay spread L d (in sample units), the transmitter and the receiver feed back the channel information obtained by the transmitter and the receiver based on the channel and / or signals (e.g., channel state information reference signals or CSI-RS, synchronization signals, etc.) to the receiver or the transmitter, or obtain the channel information corresponding thereto by using the channel or signals (sounding reference signals, SRS, etc.) that can be obtained. Therefore, the number of two-dimensional resources that can be used in the region d-D can be N d x N D = N F / L d x N T / L D .

[0071] Figure 3 An example of a resource grid of the region d-D is shown. The domain d-D can be represented as a two-dimensional grid 301 including N d block resources 307 indicating delay and N D block resources 303 indicating Doppler. One block 311 within the two-dimensional grid can be uniformly divided into two-dimensional d-D domain resources 305 of length L d and 309 of length L D . Such division can be performed according to the degree of time delay and Doppler spread of the channel, and information about the division can be determined by the BS based on the maximum allowed delay and the designed motion speed of the UE, or can be configured based on the channel detected through channel estimation and feedback of the channel through SRS or CSI-RS between the transmitter and the receiver, and can include at least one of the methods indicated through a higher layer signal. The divided resources can include block resources from p(1) to p(Nd,ND).

[0072] The method proposed in the present disclosure is described below. The transmitter first converts a transmission symbol (or transmission information) into binary information through sparse mapping. The binary information is a value of 0 or 1, and the sparse mapping is mapped using a transform vector in which a small number of 1s are included. There are various methods for sparse mapping, for example, a method of transforming a specific position of a transform vector to 1 can be used. In a method of transforming a 2-bit transmission symbol into a 4-bit sparse vector, 00 can be transformed into 1000, 01 can be transformed into 0100, 10 can be transformed into 0010, and 11 can be transformed into 0001. Each transformed sparse vector includes one 1, and thus the sparsity K is represented as 1.

[0073] Thereafter, the transform vector is mapped to a d-D resource grid and transformed into a signal of a t-f domain. Some signals in the domain t-f transformed according to scheduling are selected and transmitted through an OFDM signal.

[0074] The receiver first receives the OFDM symbol and converts it into a signal in the domain d-D. The receiver can use a reception algorithm based on compressed sensing (CS), and can identify whether there is information about the signal in the d-D domain for each d-D block resource in order to reconstruct the desired binary signal through CS energy detection. The reconstructed binary signal is converted into the original symbol through sparse demapping.

[0075] Hereinafter, the proposed transmission method will be described in more detail. When a binary transmission vector (i.e., one or more transmission symbols) transmitted in a delay-Doppler domain is s, a sparse vector p can be acquired through a function f(s; b; M; K). That is, a stream corresponding to each bit of each binary transmission vector s is mapped to an M-dimensional sparse vector (here, for example, M = bN d N D / N s , N s is the length of s) through a mapper having sparsity K. As a result, the maximum number of resources in the d-D domain is N d xN D blocks, and data (0 or 1) is mapped to each block. Accordingly, the mapped p can be expressed as the following sparse matrix P.

[0076] [Equation 1]

[0077]

[0078] 1 LDxLd is the (L D / 2)th value and the (L d / 2)th value are 1 and the remaining values are 0. When the sparse matrix P is expanded in the t-f domain, a two-dimensional transmission signal X can be generated through the following [Equation 2].

[0079] [Formula 2]

[0080]

[0081] AoB is a Hadamard product between A and B matrices.F NF is a Fourier transform matrix of size N, Φ is a selection matrix that selects m columns in the t-f domain, and Φ' is a matrix obtained by replacing Φ in the d-D domain. Φ is used to select a frequency band, and the transmitter performs additional compression in the frequency domain in order to configure a guard band for managing user multiplexing or / and potential interference between adjacent channels based on Φ.

[0082] Through the above process, a total of 2-step compression is applied to the transmission of the vector s, where the first compression is a sparse compression in the d-D domain, and the second compression corresponds to a compression by frequency band mapping in the t-f domain.

[0083] Figure 4 An example of the extension to the t-f domain proposed in the present disclosure is shown. That is, Figure 3 The p blocks configured in Figure 4 are extended in two dimensions of time 403 and frequency 405 in . Since the transformation to the t-f domain is performed by the size of the FFT, information about all p blocks is uniformly extended to the two-dimensional resource 401. However, it can not be possible to actually transmit all the information in the communication system. It is necessary to transmit a signal through a specific frequency resource in the communication system to construct multiplexing and / or a guard band with other users.

[0084] Figure 5 An example of the allocation of t-f domain resources proposed in the present disclosure is shown. As Figure 5 shown, information about the extended P blocks is transmitted in some regions 507 in the frequency band of time 503 and frequency 505. At this time, the method is determined by a high layer signal in the first compression (sparse compression in the d-D domain) or a pre-defined rule, and the transmitter transmits the position and length of the frequency band in which the signal is transmitted using a control channel or a high layer signal in the second compression (signal transmission in some regions of the t-f domain). Specifically, the information for the first compression can include at least one of the length L d and / or L D , the number N d and / or N D , the number N F and / or N T , the length of the sparse vector, the method of sparse mapping rule, and sparsity K, and in addition, the information for the second compression can include information about the frequency band in which the signal is transmitted, the position of the subcarrier, the frequency resource and / or the time resource expressed in a predetermined or pre-configured unit, and the position of the time symbol.

[0085] The transmitted signal can be received by the receiver via a channel and represented as a vector, such that the received vector y n may be represented as [Equation 3].

[0086] [Equation 3]

[0087]

[0088] G n is a channel matrix, x n is the nth column vector of the matrix X, and z is a noise vector indicating the addition of white Gaussian noise. The channel matrix G can be decomposed as [Equation 4].

[0089] [Equation 4]

[0090]

[0091] The matrix Λ n represents the frequency channel values in a diagonal form. That is, when the frequency channel vector is h n , and by applying [Equation 4] to [Equation 3], the following [Equation 5] can be obtained.

[0092] [Equation 5]

[0093]

[0094] Since the compressed signal in the d-D domain is transmitted to N T symbols, a matrix T of N symbols can be represented as the following [Equation 6].

[0095] [Equation 6]

[0096]

[0097] The received signal is transformed to the d-D domain. U corresponds to and the d-D channel response, and [Equation 6] can be simply represented as [Equation 7].

[0098] [Equation 7]

[0099]

[0100]

[0101] In order to reconstruct the received signal using the CS algorithm, [Equation 7] is divided into a sub-matrix form, and by applying this, [Equation 8] is obtained.

[0102] [Equation 8]

[0103]

[0104] The transform symbol means a transform as shown in [Equation 9].

[0105] [Equation 9]

[0106]

[0107] The finally transformed [Equation 9] can be expressed as follows.

[0108] [Equation 10]

[0109]

[0110]

[0111] G is a d-D domain channel response, and is the same for all d-D domain resource blocks due to the two-dimensional cyclic correlation property between the t-f and d-D domains. The receiver can select the resource blocks in order from the highest energy according to each resource block for [Equation 10]. This is expressed by [Equation 11] below.

[0112] [Equation 11]

[0113]

[0114] Since the matrix P includes 0 and 1, the operation of the receiver is the same as the energy of the resource block to which 1 is mapped by the d-D channel. Therefore, the receiver that does not need to use a pilot signal can reconstruct the transmission signal by observing the d-D region in which the energy of the entire channel is received. In addition, since one data symbol is allocated to several t-f resources without being mapped to a specific resource of the t-f domain, robustness to interference generated due to phase noise can be achieved. The received signal is the same as performing two-dimensional convolution of the channel impulse response using a sparse vector in the d-D domain. As a result, information is transmitted according to whether there is a signal in a specific resource block of the d-D domain resource grid.

[0115] Figure 6 The transmission operation of the transmitter proposed in the present disclosure is shown. Referring to Figure 6 , in operation 601, the transmitter configures configuration information for compressed transmission of the method proposed in the present disclosure and transmits the configuration information to the receiver through a layer signal. The configuration information for the compressed transmission can include information on the length L d and / or L D , the number N d and / or N D , the number N F and / or NT , at least one piece of information on the length of the sparse vector, the method or rule of sparse mapping, sparsity K, and some information can be predetermined, so it can not be transmitted. Thereafter, the transmitter determines detailed scheduling information, particularly allocation information on the frequency axis, and transmits the information to the receiver through a control channel or high layer signaling in operation 603. The scheduling information can include information on frequency band resources and / or time resources for transmitting the converted signal through the method proposed in the disclosure, which corresponds to the information for the second compression as described above.

[0116] The transmitter converts the transmission signal into a sparse vector through the above-described method in operation 605 and maps it to a pre-configured d-D domain block resource in operation 607. The transmitter converts the mapped signal into a t-f domain signal through the above-described method in operation 609 and allocates it to a t-f domain resource based on the scheduling information such as frequency allocation determined in operation 603. At this time, the transmitter can multiplex the converted signal with other signals. Thereafter, in operation 613, the transmitter converts the converted signal into an OFDM signal and transmits it to the receiver.

[0117] Figure 7 The reception operation of the receiver proposed in the disclosure is illustrated. Referring to Figure 7 , the receiver receives configuration information for compressed transmission such as sparse vector compression, mapping rule, resource configuration information of d-D domain from the transmitter through high layer signaling in operation 701. The configuration information for compressed transmission can include at least one piece of information on the length L d and / or L D , the number N d and / or N D , the number N F and / or N T , the length of the sparse vector, the method or rule of sparse mapping, and sparsity K, and some information can be predetermined, so it can not be transmitted. Thereafter, in operation 703, the receiver receives scheduling information in the actual t-f domain (i.e., OFDM signal allocation information) through high layer signaling or a control channel. The scheduling information can include information on frequency band resources and / or time resources for transmitting the converted signal proposed in the disclosure, which is information for the second compression as described above. The receiver receives the OFDM signal according to the scheduling information received in operation 703. Thereafter, in order to reconstruct the original signal, the receiver can reconstruct the sparse vector of the d-D domain transmitted by the method of measuring the energy size of each d-D domain block resource by the signal processing proposed in the disclosure, and reconstruct the original signal by performing sparse vector demapping on the reconstructed sparse vector.

[0118] Figure 8is a graph showing performance according to the embodiment proposed in the present disclosure. Figure 8 Performance is shown in a case where the symbol length is variable for data transmission.

[0119] In Figure 8 , when the number of symbols N t for 20, 40, 60, and 80, packet error rate (PER) performance is shown according to signal-to-noise ratio (SNR). This means that transmission is made with d-D domain resource blocks of constant size, not variable length L D is performed. Based on the result, it can be observed that the influence of interference between blocks in the d-D domain according to constant Doppler spread. According to Figure 8 , when N t = 60 and 80 for SNR = -6.5 and -9 dB, 0.001 PER can be achieved. On the other hand, when N t is small such as 20 to 40, performance deteriorates even with high SNR, and PER becomes poor. This is because errors occur due to interference between resource blocks generated in the d-D domain, which is a phenomenon similar to interference between symbols in the t-f domain. That is, in order to effectively perform the method proposed in the present disclosure, it is important to properly configure d = -D domain block resources (L D and the size of L d ) based on the Doppler spread statistics of the channel to avoid interference. For this, the transmitter and receiver can acquire the channel state before performing the present disclosure, as proposed in the present disclosure.

[0120] Figure 9 is another graph showing performance according to the example proposed in the present disclosure. Figure 9 Performance is shown when the size of the frequency band is changed at various Doppler speeds.

[0121] Figure 9 It is shown that the technology proposed in the present disclosure is sensitive to the Doppler frequency (fD) in the frequency axis and the compression rate m (%) in the frequency axis. As shown in the result of Figure 9 , when an appropriate Doppler domain block distance LD is configured for the Doppler frequency, 0.1 PER (a general data transmission requirement in a cellular network) can be achieved even if transmission is performed using only about 40% of the frequency resources compared to the bandwidth. When the Doppler frequency is further reduced (when the UE speed is reduced), data transmission requirements can be achieved even if only about 10% of the subcarriers compared to the bandwidth are used. Therefore, the proposed method can show that a high level of frequency region compression is possible.

[0122] Figure 10 is another graph showing performance according to the example proposed in the present disclosure. Figure 10Performance is shown when the degree of sparsity and the size of time symbol used for transmission are changed.

[0123] Figure 10 Performance is shown when the number of time symbols N t PER performance results according to the sparsity of d-D region when the number of time symbols N t is changed. Here, sparsity rate a is used to compare sparsity, which means the number of blocks actually used for transmission among all M blocks. When N t is very large (e.g., N t = 80), 0.1 PER can be achieved even if a > 0.5, but as N t becomes smaller, PER is more sensitive to sparsity rate a. For example, in the case of N max = 40, 0.01 PER cannot be achieved even if signals are transmitted to only one or two blocks.

[0124] Figure 11 is another graph showing performance according to the example proposed in the present disclosure. Figure 11 Performance of the proposed method is shown under various channel conditions.

[0125] In Figure 11 , PER performance according to channel characteristics such as maximum delay spread (D tap ) and the number of channel taps (N tap ) is shown according to SNR. When N max = 20, D tap = 70, and 20 taps are uniformly and randomly distributed over 70 taps to generate a channel having high selectivity in the frequency domain. It is observed that as N max decreases with the same D max , the average delay interval between taps increases, and the final channel selectivity further increases. On the other hand, when D tap decreases, the channel selectivity decreases. As a result, as the channel selectivity increases, the SNR required to receive at 0.01 PER can be reduced, but the effect of the channel in the t-f domain channel is small. This means that the proposed method is not sensitive to phase noise added in the t-f domain.

[0126] Figure 12 Performance is shown according to the fifth embodiment proposed in the present disclosure. Figure 12 Performance is shown in comparison with various conventional schemes.

[0127] Figure 12The PER performance of the multi-dimensional sparse vector compression (M-PVS) according to the present disclosure is shown in comparison with conventional techniques, such as OFDM [1], SVC

[22] , and PL-SVC [3] ([1] Zaidi, Ali, et al. "5G Physical Layer: principles, models and technology components," Academic Press, 2018 [2] H. Ji et al., "Sparse Vector Coding of Control Channel for Ultra-Reliable and Low Latency Communications," IEEE Trans. Wireless Commun., 2017 [3] H. Ji, et al., "Pilot-Less Sparse Vector Coding for Short Packet Transmission," IEEE Commun. Lett., vol. 8, no. 4, 2019). The OFDM scheme uses 30% of the resources for transmitting a signal as an overhead for two-dimensional pilot signal transmission. In the case of sparse vector coding (SVC), the decoding requires a pilot symbol, but the transmission is performed without the pilot symbol, and the resources for the SVC and the pilot-less sparse vector coding are the same. As a result, the performance of the SVC is the lowest since the SVC cannot be effectively performed without the pilot symbol. In the case of the PL-SVC, the main assumption of the decoding algorithm is that the channel coefficients are almost constant during the data transmission interval. Therefore, even in a high SNR, the performance deterioration due to the channel variation caused by the Doppler is observed. The method proposed in the present disclosure (M-SVC) has a lower spectral efficiency compared to the OFDM, but can obtain better PER performance without the overhead of the pilot signal in the t-f domain, i.e., without channel estimation. This is useful for a system in which the energy efficiency is more important than the spectral efficiency, such as a data network with a very large millimeter wave or Terra Hertz spectrum having a significantly large frequency band resource. In addition, each performance operation according to the proposed M-SVC can be quickly processed by the software of the transceiver without adding hardware.

[0128] To implement the above-described embodiments, the transceiver, memory, and processor of the UE and the UB are shown in Figure 13 and Figure 14 respectively.

[0129] Figure 13 is a block diagram showing the structure of a transmitter according to an embodiment of the present disclosure. The transmitter can be a BS or a UE.

[0130] Reference Figure 13 The transmitter can include a data signal generator 1300, a multiplexer 1310, a control signal generator 1320, an RF signal generator 1330, and a memory / controller 1340. However, elements of the transmitter are not limited thereto, for example, the UE can include more or less elements than those described above. Also, the data signal generator 1300, the multiplexer 1310, the control signal generator 1320, the RF signal generator 1330, and the memory / controller 1340 can be implemented in the form of one chip.

[0131] According to an embodiment of the disclosure, the data signal generator 1300 is a device for modulating a transmission symbol to generate a transmission sample. The control signal generator 1320 is a device for modulating control information and generating a transmission sample. The multiplexer 1310 is a device for multiplexing the generated data and control signals. The RF signal generator 1330 is a device for converting a digital signal into an analog signal, up-converting the analog signal to an RF signal, and transmitting the generated signal to an antenna, and the signal can include control information and data. Also, the RF signal generator 1330 can be referred to as a transmitter, a transceiver, or the like.

[0132] According to an embodiment of the disclosure, the memory / controller 1340 can store programs and data required for the operation of the BS. Also, the memory / controller 1340 can store control information or data included in a signal transmitted by the transmitter. The memory / controller 1340 can be configured by a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media. Also, the memory / controller 1340 can be configured by a plurality of memories and processors. According to an embodiment of the disclosure, the memory / controller 1340 can store information for fast data processing, data, and programs. Also, operations performed by the multiplexer 1310, the control signal generator 1320, and the data signal generator 1300 can be performed by the memory / controller 1340.

[0133] According to an embodiment of the disclosure, the memory / controller 1340 can control a series of processes based on the operation of the transmitter according to an embodiment of the disclosure.

[0134] Figure 14 is a block diagram illustrating a structure of a receiver according to an embodiment of the disclosure. The receiver can be a UE or a BS.

[0135] Reference Figure 14The UE can include an RF signal receiver 1430, a data signal receiver 1400, a demultiplexer 1410, a control signal receiver 1420, and a memory / controller 1440. However, the elements of the UE are not limited thereto, and for example, the UE can include more or less elements than those described above. Also, the RF signal receiver 1430, the data signal receiver 1400, the demultiplexer 1410, the control signal receiver 1420, and the memory / controller 1440 can be implemented in the form of one chip.

[0136] According to an embodiment of the disclosure, the RF signal receiver 1430 can receive a signal of the transmitter. The signal can include control information and data. To this end, the RF signal receiver 1430 can be configured by an RF receiver for down-converting and amplifying a frequency of a received signal. Also, the RF signal receiver 1430 can be referred to as a receiver, a transceiver, or the like. Also, the signal is transmitted to a corresponding receiver, that is, a control channel is transmitted to the control signal receiver 1420, a data channel is transmitted to the data signal receiver 1400 through the demultiplexer 1410, and the data signal can be reconstructed by the memory / controller 1440 based on a reconstruction command from the control channel.

[0137] According to an embodiment of the disclosure, the memory / controller 1440 can store a program and data required for the operation of the receiver. Also, the memory / controller 1440 can store control information or data included in a signal transmitted by the transmitter. The memory / controller 1440 can be configured by a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media. Also, the memory / controller 1440 can be configured by a plurality of memories. According to an embodiment of the disclosure, the memory / controller 1440 can store information, data, and a program for fast data signal processing. Also, operations performed by the demultiplexer 1410, the control signal receiver 1420, and the data signal receiver 1400 can be performed by the memory / controller 1440.

[0138] According to an embodiment of the disclosure, the memory / controller 1440 can control a series of processes so that the BS can operate according to an embodiment of the disclosure.

[0139] The method according to various embodiments described in the claims or the disclosure can be implemented by hardware, software, or a combination of hardware and software.

[0140] When the method is implemented in software, a computer-readable storage medium may be provided for storing one or more programs (software modules). The one or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors within an electronic device. At least one program may include instructions causing the electronic device to perform the methods as defined in the appended claims and / or as disclosed herein according to various embodiments of this disclosure.

[0141] The program (software module or software) can be stored in non-volatile memory, including random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), disk storage devices, optical disc ROM (CD-ROM), digital multifunction disc (DVD), or other types of optical storage devices or magnetic tape. Optionally, any combination of some or all of these can form the memory storing the program. Furthermore, an electronic device may include multiple such memories.

[0142] Furthermore, the program can be stored on a connectable storage device that can be accessed by the electronic device via a communication network such as the Internet, intranet, local area network (LAN), wide area network (WLAN), and storage area network (SAN), or a combination thereof. This storage device can access the electronic device via an external port. Additionally, a separate storage device on the communication network can access portable electronic devices.

[0143] In the detailed embodiments of this disclosure described above, elements included in this disclosure are represented in a singular or plural form according to the presented detailed embodiments. However, for ease of description, singular or plural forms have been suitably chosen as presented, and this disclosure is not limited to elements represented in a singular or plural form. Thus, an element represented in a plural form may also include a single element, or an element represented in a singular form may also include multiple elements.

[0144] The embodiments of this disclosure described and illustrated in the specification and accompanying drawings are merely specific examples presented to facilitate the explanation of the technical content of this disclosure and to aid in understanding it, and are not intended to limit the scope of this disclosure. That is, it will be apparent to those skilled in the art that other variations based on the technical ideas of this disclosure can be implemented. Furthermore, the various embodiments described above can be combined as needed. For example, a portion of one embodiment of this disclosure can be combined with a portion of another embodiment to operate a base station and a terminal. Furthermore, the embodiments of this disclosure can be applied to other communication systems, and other variations based on the technical ideas of the embodiments can be implemented. For example, these embodiments can also be applied to LTE, 5G, or NR systems.

Claims

1. A method performed by a transmitter in a communication system, the method comprising: Send configuration information for transmitting signals to the receiver; Determine the frequency resources to be used for transmitting signals, and send scheduling information indicating the frequency resources to the receiver; The signal is converted into a sparse vector by mapping the information included in the signal to be transmitted onto the corresponding sparse vector, according to the configuration information. Map the sparse vector to the delayed Doppler domain; Convert the sparse vector of the delayed Doppler domain mapping into a signal in the time-frequency domain; Mapping a portion of the time-frequency domain signal to the frequency resource corresponding to the scheduling information; and The time-frequency domain signal is converted into an orthogonal frequency division multiplexing (OFDM) signal, and the generated OFDM signal is sent to the receiver. Sparse vectors correspond to vectors that contain a very small number of 1s and the rest are 0s.

2. The method according to claim 1, wherein, The configuration information includes at least one of information about the configuration of the delayed Doppler domain or sparse mapping rule information related to the mapping between information and sparse vectors.

3. The method according to claim 2, wherein, Information regarding the configuration of the delay-Doppler domain includes at least one of the following: the number of resources on the delay axis, the number of resources on the Doppler axis, the sign units of the delay axis, or the sample units of the Doppler axis.

4. The method according to claim 1, wherein, The mapping from sparse vectors to the delayed Doppler domain also includes: The corresponding bits of the sparse vector are mapped to resource blocks included in the delayed Doppler domain.

5. A method performed by a receiver in a communication system, the method comprising: Receive configuration information from the transmitter for receiving signals; Receive from the transmitter scheduling information for receiving signals, the scheduling information indicating frequency resources for the signals; Receive an orthogonal frequency division multiplexing (OFDM) signal from the frequency resource from the transmitter; convert the received OFDM signal into a delayed Doppler domain signal; Compressed sensing is used to determine whether the delayed Doppler domain signal is located in the corresponding resource block, and a sparse vector corresponding to the information included in the reconstructed and received OFDM signal is constructed based on this determination; and The information is obtained by applying sparse vector mapping to the reconstructed sparse vector. Sparse vectors correspond to vectors that contain a very small number of 1s and the rest are 0s.

6. The method according to claim 5, wherein, The configuration information includes at least one of information about the configuration of the delayed Doppler domain or sparse mapping rule information related to the mapping between information and sparse vectors.

7. The method of claim 6, wherein the information regarding the configuration of the delayed Doppler domain includes at least one of the number of resources on the delay axis, the number of resources on the Doppler axis, the sign unit of the delay axis, or the sample unit of the Doppler axis.

8. A transmitter in a communication system, the transmitter comprising: transceiver; as well as The controller is configured as follows: Send configuration information for transmitting signals to the receiver; Determine the frequency resources to be used for transmitting signals, and send scheduling information indicating the frequency resources to the receiver; The signal is converted into a sparse vector by mapping the information included in the signal to be transmitted onto the corresponding sparse vector, according to the configuration information. Map the sparse vector to the delayed Doppler domain; Convert the sparse vector of the delayed Doppler domain mapping into a signal in the time-frequency domain; Mapping a portion of the time-frequency domain signal to the frequency resource corresponding to the scheduling information; and The time-frequency domain signal is converted into an orthogonal frequency division multiplexing (OFDM) signal, and the generated OFDM signal is sent to the receiver. Sparse vectors correspond to vectors that contain a very small number of 1s and the rest are 0s.

9. The transmitter according to claim 8, wherein, The configuration information includes at least one of information about the configuration of the delayed Doppler domain or sparse mapping rule information related to the mapping between information and sparse vectors.

10. The transmitter according to claim 9, wherein, Information regarding the configuration of the delay-Doppler domain includes at least one of the following: the number of resources on the delay axis, the number of resources on the Doppler axis, the sign units of the delay axis, or the sample units of the Doppler axis.

11. The transmitter according to claim 8, wherein, The controller is further configured to map the corresponding bits of the sparse vector to resource blocks included in the delayed Doppler domain.

12. A receiver in a communication system, the receiver comprising: Transmitter; as well as The controller is configured as follows: Receive configuration information from the transmitter for receiving signals; Receive from the transmitter scheduling information for receiving signals, the scheduling information indicating frequency resources for the signals; Receive orthogonal frequency division multiplexing (OFDM) signals from the frequency resources from the transmitter; The received OFDM signal is converted into a delayed Doppler domain signal; Compressed sensing is used to determine whether the delayed Doppler domain signal is located in the corresponding resource block, and a sparse vector corresponding to the information included in the reconstructed and received OFDM signal is constructed based on this determination; and The information is obtained by applying sparse vector mapping to the reconstructed sparse vector. Sparse vectors correspond to vectors that contain a very small number of 1s and the rest are 0s.

13. The receiver according to claim 12, wherein, The configuration information includes at least one of information about the configuration of the delayed Doppler domain or sparse mapping rule information related to the mapping between information and sparse vectors.

14. The receiver according to claim 13, wherein, Information regarding the configuration of the delay-Doppler domain includes at least one of the following: the number of resources on the delay axis, the number of resources on the Doppler axis, the sign units of the delay axis, or the sample units of the Doppler axis.

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