Signal transmission method, signal receiving method, device and equipment
The proposed signal transmission method for OTFS systems in high-speed scenarios addresses the high PAPR issue by mapping modulation symbols into a delay-time domain, performing preset processing, and applying pulse shaping, resulting in improved power efficiency and performance.
Patent Information
- Application Number
- JP2024500382
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2021-07-05
- Filing Date
- 2022-07-04
- Publication Date
- 2025-06-05
- Estimated Expiration
- 2042-07-04
AI Technical Summary
OTFS systems face challenges in high-speed moving scenarios due to high Peak-to-Average Power Ratio (PAPR), which affects performance and power efficiency.
A signal transmission method that maps modulation symbols into a delay-time domain, performs a preset processing to obtain time domain sampling points, and applies pulse shaping before transmission, thereby reducing PAPR while maintaining performance in high-speed scenarios.
The method effectively reduces PAPR, improves power efficiency, and ensures the performance of OTFS in high-speed moving scenarios by transforming the signal processing in the delay-time domain.
Smart Images

Figure 0007689237000043 
Figure 0007689237000044 
Figure 0007689237000045
Abstract
Description
[Technical field]
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to a Chinese patent application filed on July 5, 2021, bearing application number 202110758863.5 and entitled "Signal Transmission Method, Receiving Method, Apparatus and Equipment", the entire contents of which are incorporated herein by reference.
[0002] The present application relates to the field of communications technology, and in particular to signal transmission methods, receiving methods, devices and equipment. [Background technology]
[0003] At present, Orthogonal Frequency Division Multiplexing (OFDM) technology realizes high-rate transmission while effectively combating inter-symbol interference caused by multipath channels. OFDM symbols generate low-complexity launch signals through Inverse Fast Fourier Transform (IFFT), after which all subcarrier signals are superimposed to make the time-domain waveform have a very high Peak-to-Average Power Ratio (PAPR). The high PAPR results in a reduction in the efficiency of the power amplifier in the launcher and the ratio of signal quantization noise in the digital-to-analog converter and analog-to-digital converter. Before improving the power efficiency of the subcarrier mapping in the launcher, a Discrete Fourier transform (DFT) processing module is first added to improve power efficiency, so that the resulting waveform looks like a single carrier, and this waveform is called Discrete Fourier Transform-Spread- Orthogonal frequency division multiplexing (DFT-S-OFDM) and is used in uplink Long Term Evolution (LTE) to improve power efficiency. In high-speed moving scenarios, Doppler shifts severely destroy the orthogonality between subcarriers, which leads to inter-carrier interference, which further affects the performance of OFDM in high-speed moving scenarios. For inter-carrier interference, related technologies mainly use carrier frequency offset estimation and compensation. However, as the speed constantly improves, the coherent time of the channel decreases, making it difficult to estimate and compensate for the frequency offset.
[0004] To combat the Doppler shift in high-speed moving scenarios, Orthogonal Time Frequency Space (OTFS) has recently been proposed as a new type of two-dimensional multi-carrier modulation technology. Unlike OFDM, which adopts time-frequency domain multiplexing symbols, OTFS adopts delay-Doppler domain multiplexing. The transmitted symbols are transformed into the time-frequency domain through Inverse symplectic Fourier transform (ISFFT), and in the delay-Doppler domain, the channel exhibits the characteristics of slowly varying and sparse, which can effectively combat the double spreading effect in the time-frequency domain caused by the fast time-varying channel. However, as a multi-carrier system, it also faces the high PAPR problem, and how to design a system to ensure the performance of OTFS in high-speed moving scenarios while simultaneously reducing the PAPR is currently an issue that needs to be resolved urgently. Summary of the Invention [Problem to be solved by the invention]
[0005] The embodiments of the present application provide a signal transmission method, a receiving method, an apparatus, and a device that can reduce the PAPR while ensuring the performance of OTFS in high-speed moving scenarios. [Means for solving the problem]
[0006] According to a first aspect, there is provided a method of signal transmission, the method comprising: A transmitter maps the modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix; The transmitting end performs a first preset processing on the first delay-time domain symbol matrix to obtain time domain sampling points, and transmits the time domain sampling points after pulse shaping.
[0007] According to a second aspect, there is provided a method of receiving a signal, the method comprising: The receiving end performs a second predetermined processing on the received time-domain signal to obtain a delay-time domain received signal; A receiving end performs channel estimation in a delay-Doppler domain according to a pilot sequence in a delay-time domain to obtain channel-related parameters; The receiving end performs delay-time domain symbol detection on the received signal based on the channel-related parameters.
[0008] According to a third aspect, there is provided a signal transmission device, the device comprising: a mapping unit for mapping the modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix; and a first processing unit for performing a first preset processing on the first delay-time domain symbol matrix to obtain time domain sampling points, and transmitting the time domain sampling points after pulse shaping.
[0009] According to a fourth aspect, there is provided a signal receiving apparatus, the apparatus comprising: a second processing unit for performing a second predetermined processing on the received time-domain signal to obtain a delay-time domain received signal; a channel estimation unit for performing channel estimation in a delay-Doppler domain based on a pilot sequence in a delay-time domain to obtain channel-related parameters; and a symbol detection unit for performing delay-time domain symbol detection on the received signal based on the channel-related parameters.
[0010] According to a fifth aspect there is provided a terminal comprising a processor, a memory and a program or instructions stored in the memory and operable to run on the processor, the program or instructions being operable when executed by the processor to implement the steps of a method according to the first or second aspect.
[0011] According to a sixth aspect, a terminal is provided, comprising a processor and a communication interface, wherein the processor is adapted to map modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix, perform a first preset processing on the first delay-time domain symbol matrix to obtain time domain sampling points and transmit after pulse shaping, or the processor is adapted to perform a second preset processing on a received time domain signal to obtain a delay-time domain received signal, perform channel estimation in a delay-Doppler domain based on a delay-time domain pilot sequence to obtain channel-related parameters, and perform delay-time domain symbol detection on the received signal based on the channel-related parameters.
[0012] According to a seventh aspect, there is provided a network side device comprising a processor, a memory, and a program or instructions stored in the memory and operable to run on the processor, the program or instructions, when executed by the processor, realising the steps of the method according to the first or second aspect.
[0013] According to an eighth aspect, a network side device is provided, comprising a processor and a communication interface, where the processor is adapted to map modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix, perform a first preset processing on the first delay-time domain symbol matrix to obtain time domain sampling points and transmit after pulse shaping, or the processor is adapted to perform a second preset processing on a received time domain signal to obtain a delay-time domain received signal, perform channel estimation in a delay-Doppler domain based on a delay-time domain pilot sequence to obtain channel-related parameters, and perform delay-time domain symbol detection on the received signal based on the channel-related parameters.
[0014] According to a ninth aspect, there is provided a readable storage medium having a program or instructions stored thereon, the program or instructions, when executed by a processor, performing steps of the method according to the first aspect or performing steps of the method according to the second aspect.
[0015] According to a tenth aspect, there is provided a chip, the chip including a processor and a communication interface, the communication interface coupled to the processor, the processor running a program or instructions to implement the method of the first aspect or used to implement the method of the second aspect.
[0016] According to an eleventh aspect, there is provided a computer program / program product, the computer program / program product being stored on a non-transitory storage medium, the computer program / program product being executed by at least one processor to implement the steps of the method according to the first aspect or to implement the steps of the method according to the second aspect. Effect of the Invention
[0017] In the embodiment of the present application, the modulation symbols are mapped into a delay-time domain to obtain a first delay-time domain symbol matrix, a first preset processing is performed on the first delay-time domain symbol matrix to obtain a time domain sampling point, and then pulse shaping is performed before transmission, so that the transmission process reduces the PAPR on the premise of maintaining the characteristics of a single carrier and ensuring the performance of OTFS in high-speed moving scenarios. [Brief description of the drawings]
[0018] [Figure 1] 1 is a structural diagram of a wireless communication system to which an embodiment of the present application can be applied; [Diagram 2] 2 is a flowchart of a signal transmission method according to an embodiment of the present application. [Diagram 3] 2 is a flowchart of modulation / demodulation according to an embodiment of the present application. [Figure 4] FIG. 2 is a schematic diagram of a delay-time domain pilot pattern design according to an embodiment of the present application; [Diagram 5] 2 is a flowchart of a signal receiving method according to an embodiment of the present application; [Figure 6] 2 is a signal processing flow chart according to an embodiment of the present application. [Figure 7] 1 is a structural schematic diagram of a signal transmitting device according to an embodiment of the present application; [Figure 8] 1 is a structural schematic diagram of a signal receiving device according to an embodiment of the present application; [Figure 9] 1 is a structural schematic diagram of a communication device according to an embodiment of the present application; [Figure 10] FIG. 2 is a schematic diagram of a hardware structure for implementing a terminal according to an embodiment of the present application; [Figure 11] FIG. 2 is a structural schematic diagram of a network side device according to an embodiment of the present application; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The following clearly describes the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application are all within the scope of protection of the present application.
[0020] The terms "first," "second," etc. in the specification and claims of the present application are intended to distinguish between similar objects and are not intended to describe a particular order or sequence. It is to be understood that the terms so used are interchangeable where appropriate, such that the embodiments of the present application may be performed in an order other than that shown or described herein, and that the objects distinguished by "first" and "second" are generally of the same type and do not limit the number of objects, e.g., the first object may be one or more. It is to be noted that "and / or" in the specification and claims represents at least one of the objects connected, and the character " / " generally represents an "or" relationship between the related objects.
[0021] It should be noted that the techniques described in the embodiments of the present application are not limited to Long Term Evolution (LTE) / LTE-Advanced (LTE-A) systems, but can also be applied to other wireless communication systems, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-carrier Frequency-Division Multiple Access (SC-FDMA), and other systems. The terms "system" and "network" in the embodiments of the present application are always used interchangeably, and the techniques described may be used in the above-mentioned systems and radio technologies, or in other systems and radio technologies. Although the following description describes a New Radio (NR) system for illustrative purposes and uses NR terminology in most of the following description, these technologies may also be used in applications other than NR system applications, such as sixth generation (6G) systems. th This may be applied to a 6G (6th Generation) communication system.
[0022] 1 shows a structural diagram of a wireless communication system to which the embodiments of the present application can be applied. The wireless communication system includes a terminal 11 and a network side device 12. Here, the terminal 11 may be called a terminal device or a user terminal (User Equipment, UE), and the terminal 11 may be a terminal side device such as a mobile phone, a tablet personal computer, a laptop computer (or called a notebook computer), a personal digital assistant (PDA), a palmtop computer, a netbook, an ultra-mobile personal computer (UMPC), a mobile Internet device (MID), an augmented reality (AR) / virtual reality (VR) device, a robot, a wearable device, a vehicle-mounted equipment (VUE), a pedestrian terminal (PUE), a smart home (home equipment having a wireless communication function, such as a refrigerator, a television, a washing machine, or furniture), etc., and the wearable device includes a smart watch, a smart bracelet, a smart earphone, a smart glasses, a smart accessory (smart bracelet, a smart hand chain, a smart ring, a smart necklace, a smart ankle bracelet, a smart anklet, etc.), a smart band, a smart clothing, a game console, etc. It should be clarified that the embodiments of the present application are not limited to a specific type of terminal 11 .The network side equipment 12 may be a base station or a core network, where the base station may be called a Node B, an evolved Node B, an access point, a base transceiver station (BTS), a radio base station, a radio transceiver, a basic service set (BSS), an extended service set (ESS), a B node, an evolved B node (eNB), a home B node, a home evolved B node, a WLAN access point, a WiFi node, a transmitting receiving point (TRP), or any other suitable term in the art, and as long as the same technical effect is achieved, the base station is not limited to a specific technical term, and it should be explained that in the embodiments of this application, only a base station in an NR system is taken as an example, but the specific type of the base station is not limited.
[0023] In the following, the signal transmitting method, the signal receiving method and the device according to the embodiments of the present application will be described in detail through several embodiments and their application scenarios in conjunction with the drawings.
[0024] FIG. 2 is a flowchart of a signal transmission method according to an embodiment of the present application. As shown in FIG. 2, the method includes the following steps:
[0025] Step 200, the launch terminal maps modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix; It should be noted that the launching end may be a network side device or a terminal.
[0026] Mapping the modulation symbols in the delay-time domain means placing the modulation symbols onto a delay-time domain resource grid.
[0027] Optionally, the delay-time domain resource grid is a two-dimensional planar grid with the delay dimension as rows and the time dimension as columns.
[0028] Because OTFS multiplexes symbols in the delay-Doppler domain, in order to reduce the PAPR in high-speed moving scenarios, the launch end obtains a first delay-time domain symbol matrix by placing the modulation symbols into a delay-time domain resource grid.
[0029] Here, the embodiment of the present application does not limit the type of the modulation symbol, for example, the modulation symbol may be a Quadrature Amplitude Modulation (QAM) symbol.
[0030] Step 201, the launch end performs a first preset processing on the first delay-time domain symbol matrix to obtain time domain sampling points, which are then pulse-shaped and then transmitted.
[0031] Optionally, the first pre-defined processing includes transforming the delay-time domain symbol matrix to a delay-Doppler domain and then transforming from the delay-Doppler domain to a time-frequency domain to obtain a time-frequency domain signal, also referred to as a time-domain sampling point or a time-domain transmitted signal.
[0032] In the embodiment of the present application, the modulation symbols are mapped into a delay-time domain to obtain a first delay-time domain symbol matrix, a first preset processing is performed on the first delay-time domain symbol matrix to obtain a time domain sampling point, and then pulse shaping is performed before transmission, so that the transmission process reduces the PAPR on the premise of maintaining the characteristics of a single carrier and ensuring the performance of OTFS in high-speed moving scenarios.
[0033] Optionally, performing a first preset process on the first delay-time domain symbol matrix includes: performing a discrete Fourier transform (DFT) in a time dimension on the first delay-time domain symbol matrix to obtain a first delay-Doppler domain symbol matrix; performing a Doppler dimension extension on the first delay-Doppler domain symbol matrix to obtain a second delay-Doppler domain symbol matrix; performing an inverse discrete Fourier transform (IDFT) in a Doppler dimension on the second delay-Doppler domain symbol matrix to obtain a second delay-time domain symbol matrix; The method includes performing a vectorization process on the second delay-time domain symbol matrix to obtain time domain sampling points, and arranging the time domain sampling points, for example, by concatenating the head and tail of each column to obtain time domain sampling points.
[0034] The time domain sampling points are pulse shaped and then transmitted, that is, the launch end launches the time domain signal.
[0035] FIG. 3 is a flowchart of modulation and demodulation according to an embodiment of the present application. As shown in FIG. 3, in order to reduce the PAPR of OTFS in a high-speed moving scenario, the embodiment of the present application first maps the modulation symbols in the delay-time domain to obtain a first delay-time domain symbol matrix, then transforms the first delay-time domain symbol matrix into a delay-Doppler domain symbol matrix by DFT, and then transforms the delay-Doppler domain symbol matrix into the time-frequency domain by ISSFT, and then transforms it into the time domain, i.e., a second delay-time domain symbol matrix by Heisenberg transform, and finally performs vectorization processing on the second delay-time domain symbol matrix to obtain time domain sampling points. It should be noted that transforming a first delay-time domain symbol matrix into a delay-Doppler domain symbol matrix by DFT, then transforming the delay-Doppler domain symbol matrix into the time-frequency domain by ISSFT, and then transforming it into the time domain, i.e., into a second delay-time domain symbol matrix by Heisenberg transformation, is equivalent to transforming the first delay-time domain symbol matrix by IDFT to obtain a second delay-time domain symbol matrix.
[0036] Optionally, performing a first predetermined processing on the first delay-time domain symbol matrix to obtain time domain sampling points and transmitting after pulse shaping includes:
[0037] Step 2011, Dimension M × N 1 For the first delay-time domain symbol matrix having a length of N 1 The discrete Fourier transform DFT is performed row by row, and the dimensions are M × N 1where M represents the number of rows of the first delay-time domain symbol matrix, and N 1 represents the number of columns of the symbol matrix of the first delay-time domain, JPEG0007689237000001.jpg24170
[0038] JPEG0007689237000002.jpg51170
[0039] Step 2012, the dimension is M×N 1 Let the first delay-Doppler domain symbol matrix be of dimension M × N. 2 to a delay-Doppler domain resource grid of dimension M × N 2 Obtain a second delay-Doppler domain symbol matrix, Here, N 2 is the number of grid points in the Doppler dimension, and N 2 is N 1 An integer greater than or equal to .
[0040] JPEG0007689237000003.jpg73170
[0041] Step 2013, the dimension is M×N 2 For the second delay-Doppler domain symbol matrix with length N 2 The inverse discrete Fourier transform (IDFT) is performed row by row, and the dimensions are M × N 2 Obtain a second delay-time domain symbol matrix, TIFF0007689237000004.tif74170
[0042] JPEG0007689237000005.jpg22170
[0043] TIFF0007689237000006.tif100170
[0044] Step 2014, the dimension is M×N 2 A vectorization process is performed on the second delay-time domain symbol matrix, whose length is MN 2 and transmitting the time domain sampling points after pulse shaping the time domain sampling points; TIFF0007689237000007.tif58169Here, vec(.) represents the operation of reading a matrix column by column and converting it to a vector. Substituting equation (5) into equation (6) gives equation (7). Substituting equations (1) and (2) into equation (7) gives equation (8). Based on the properties of the Kronecker product, equation (9) is obtained. Vectorizing the delay-time domain matrix gives equation (10).
[0045] JPEG0007689237000008.jpg17170
[0046] According to equations (6)-(10), the expression of the time domain signal transmitted by the emitter can be obtained. According to the expression, the PAPR of each frame signal can be calculated. For example, by continuously generating 100,000 frames and statistically comparing them, the final result is that the PAPR of the signal transmission method according to the embodiment of the present application in 4-QAM and 16-QAM is lower than that of the OFDM and OTFS systems, and the effect of reducing the PAPR is achieved.
[0047] Further, through a fast time-varying channel, we obtain the noise-free time-domain output as follows: JPEG0007689237000009.jpg35170Substituting (10) into equation (13) gives (14), and vectorizing the delay-time domain symbol matrix gives (15).
[0048] Optionally, the first delay-time domain symbol matrix is embedded with a delay-time domain pilot sequence, and the method includes: N 1 and N 2 Demapping the second delay-Doppler domain symbol matrix into the first delay-Doppler domain symbol matrix based on a mapping relationship between and determining a pilot sequence in the delay-time domain based on an inverse discrete Fourier transform relationship between the Doppler domain and the time domain.
[0049] Compared with the time-frequency domain and the time domain, the channel has the characteristics of slowly varying, sparse, etc. in the delay-Doppler domain. In order to ensure the accuracy of channel estimation in high-speed moving scenarios, the embodiment of the present application performs channel estimation in the delay-Doppler domain. Since the embodiment of the present application multiplexes symbols in the delay-time domain, it is necessary to perform pilot pattern design in the delay-time domain based on the pilot channel estimation algorithm to meet the demand for channel estimation in the delay-Doppler domain.
[0050] Due to the input-output relationship of two-dimensional convolution in the delay-Doppler domain, it is necessary to insert guard symbols based on the maximum delay and maximum Doppler shift of the channel to ensure that pilot symbols are not contaminated by surrounding data symbols. In a channel with a fractional Doppler shift, the Doppler domain needs to insert guard symbols, but the delay dimension only needs to reserve the maximum delay range before and after the delay where the pilot is located respectively. Considering the fractional Doppler shift, the channel estimation overhead of the delay-Doppler domain is as shown in the rightmost diagram of FIG. 4, where FIG. 4 is a schematic diagram of the delay-time domain pilot pattern design according to an embodiment of the present application. The embodiment of the present application demaps the delay-Doppler domain on the rightmost diagram of FIG. 4 into the middle area based on the mapping relationship between N1 and N2 Doppler single dimensions, and then obtains the delay-time domain pilot pattern design in the left diagram of FIG. 4 based on the inverse discrete Fourier transformation relationship between the Doppler-Doppler domain and the time domain.
[0051] Optionally, the expression of a pilot pattern obtained by mapping the pilot sequence to a delay-time domain resource grid is as follows: JPEG0007689237000010.jpg97170
[0052] JPEG0007689237000011.jpg50170
[0053] In the embodiment of the present application, based on the corresponding relationship between the delay-time domain and the delay-Doppler domain, a pilot pattern design scheme in the delay-time domain is proposed, and channel estimation can be performed in the delay-Doppler domain, which can ensure the accuracy of channel estimation in fractional Doppler shift channels without relying on integer Doppler hypotheses, and reduce the overhead of pilot patterns.
[0054] FIG. 5 is a flowchart of a signal receiving method according to an embodiment of the present application. As shown in FIG. 5, the method includes the following steps:
[0055] Step 500, the receiving end performs a second preset processing on the received time domain signal to obtain a delay-time domain received signal; It should be noted that the receiving end may be a network side device or a terminal.
[0056] Optionally, the receiving end performs a second preset processing on the received time domain signal to convert the received time domain signal into a delay-time domain.
[0057] Optionally, the second preset process is an inverse operation of the first preset process, and the second preset process comprises: This includes transforming the received time-domain signal to a delay-Doppler domain and then transforming from the delay-Doppler domain to a delay-time domain to obtain a delay-time domain received signal.
[0058] Step 501, the receiving end performs channel estimation in the delay-Doppler domain according to the pilot sequence in the delay-time domain to obtain channel-related parameters; In step 502, the receiving end performs delay-time domain symbol detection on the received signal based on the channel-related parameters.
[0059] In an embodiment of the present application, the receiving end performs a second preset processing on the received time-domain signal, obtains a received signal in a delay-time domain, and performs channel estimation in the delay-Doppler domain based on the pilot sequence in the delay-time domain to obtain channel-related parameters, and further performs symbol detection in the delay-time domain on the received signal based on the channel-related parameters, thereby reducing the PAPR, improving the accuracy of channel estimation in high-speed moving scenarios, and reducing the overhead of channel estimation, and reducing the complexity of the equalization time of the proposed system.
[0060] Optionally, the signal receiving method according to the embodiment of the present application further includes: acquiring a pilot sequence in the delay-time domain.
[0061] Optionally, the delay-time domain pilot sequence is Calculating a pilot sequence in the delay-time domain based on an index value or bitmap information, the index value or bitmap information being indicated by Downlink Control Information (DCI) or Radio Resource Control (RRC) signaling, and the index value or bitmap information being a delay-Doppler domain single-point pilot pulse with a size of M×N 1 expressing a position on the Doppler dimension in a delay-Doppler resource grid as A pilot sequence of the delay-time domain is obtained by querying a pilot index table based on a pilot sequence index, where the pilot sequence index is indicated by DCI or RRC signaling, and the pilot index table is pre-configured by a protocol or indicated by broadcast signaling.
[0062] In some alternative embodiments, DCI or RRC signaling is used to indicate one pilot sequence index, and the UE obtains the pilot sequence by looking up a pilot index table, where the pilot index table is pre-configured by the protocol.
[0063] In some alternative embodiments, a pilot sequence index is indicated by DCI or RRC signaling, and the UE acquires the pilots by looking up a pilot index table, where the pilot index table is indicated by the network side device by broadcast signaling, such as a synchronization signal block (SSB), a system information block type 1 (SIB1), etc.
[0064] Optionally, performing a second predetermined process on the received time domain signal to obtain a delay-time domain received signal includes: de-vectorizing the received time domain signal to obtain a third delay-time domain symbol matrix; performing a discrete Fourier transform (DFT) on the third delay-time domain symbol matrix to obtain a third delay-Doppler domain symbol matrix; Demapping the third delay-Doppler domain symbol matrix to obtain a fourth delay-Doppler domain symbol matrix; performing an inverse discrete Fourier transform (IDFT) on the fourth delay-Doppler domain symbol matrix row by row to obtain a fourth delay-time domain symbol matrix, wherein the fourth delay-time domain symbol matrix is the delay-time domain received signal.
[0065] Performing the second preset processing on the received time domain signal may refer to the demodulation flow shown in FIG.
[0066] Optionally, performing a second predetermined processing on the received time domain signal to obtain a delay-time domain received signal includes:
[0067] Step 5001, the received length is MN 2 Vectorize the time domain signal with dimensions M×N 2 where M represents the number of rows of the third delay-time domain symbol matrix, and N 2 represents the number of columns of the symbol matrix of the third delay-time domain, Optionally, if the received length is MN 2 If we inverse-vectorize the time-domain signal, JPEG0007689237000013.jpg21170
[0068] Step 5002, the dimension is M×N 2 A discrete Fourier transform (DFT) is performed on the symbol matrix in the third delay-time domain, 2to obtain a third delay-Doppler domain symbol matrix, Optionally, transform the third delay-time domain symbol matrix into a time-frequency domain by a Weigner transform, i.e. TIFF0007689237000014.tif109170
[0069] Step 5003, the dimension is M×N 2 Demap the third delay-Doppler domain symbol matrix, 1 We obtain a fourth delay-Doppler domain symbol matrix, Demapping converts the received signal in the delay-Doppler domain into a short-range delay-Doppler domain, i.e. JPEG0007689237000015.jpg21170
[0070] Step 5004, the dimension is M×N 1 A row-by-row inverse discrete Fourier transform (IDFT) is performed on the fourth delay-Doppler domain symbol matrix, 1 , where the dimension is M×N 1 The fourth delay-time domain symbol matrix is the received signal in the delay-time domain, Here, N 1 is the number of columns of the fourth delay-Doppler domain symbol matrix, and N 1 is N 2 The following integers:
[0071] Finally, the inverse discrete Fourier transform reduces the dimensions to M × N 1 Transform the fourth delay-Doppler domain symbol matrix to the delay-time domain, i.e. JPEG0007689237000016.jpg66170
[0072] Optionally, the performing channel estimation in the delay-Doppler domain based on the pilot sequence in the delay-time domain to obtain channel-related parameters includes:
[0073] Step 5011, calculating an impulse response in a delay-Doppler domain of the pilot sequence in the delay-time domain within a detection area; Here, the detection area is the area where the pilots and their guard bands are located, for example, the area where the asterisks and circles in FIG. 4 are located.
[0074] Taking the delay-time domain pilot sequence at the origin as an example, the point-to-point correspondence in the delay-Doppler domain is as follows: JPEG0007689237000017.jpg107170
[0075] Where: JPEG0007689237000018.jpg30170, where TIFF0007689237000019.tif61152Since there is an upper bound on the maximum delay of the channel, if we place the pilot at the origin, the impulse response of the pilot sequence in the delay-Doppler domain may be expressed as: TIFF0007689237000020.tif43170
[0076] Step 5012, a correlation calculation is performed on the impulse response and the Doppler function to obtain a first correlation function; Step 5013, performing threshold detection on the amplitude of the first correlation function to obtain a threshold detection result; Optionally, threshold detection is performed based on the above equation (29) to obtain a threshold detection result.
[0077] In step 5014, channel parameters are estimated based on the threshold detection result to obtain channel-related parameters.
[0078] Based on the threshold detection result, the channel-related parameters are estimated by the following formula:
[0079] JPEG0007689237000022.jpg122170
[0080] It should be noted that the related art 1 performs threshold detection on the amplitude of the received signal in the detection area of the receiving end based on the channel estimation algorithm of the embedded pilot, and estimates the parameters corresponding to the channel based on the position and corresponding value of the pilot of the transmitting and receiving ends. This method uses the channel estimation result at the integer position to fit the effect of fractional Doppler, and has very poor performance in the channel with high speed and fractional Doppler shift. The related art 2 can solve the channel estimation at fractional Doppler shift based on the channel estimation algorithm of the correlation function, but it needs to launch a pilot alone in a single frame, and it needs to assume that the channel transmitting data in the next frame is the same as the channel through which the pilot passes, which results in low spectrum efficiency and low feasibility in the high speed movement scenario. Meanwhile, the channel estimation method according to the embodiment of the present application ensures the accuracy based on the correlation function and reduces the overhead of channel estimation at the same time, and while embedding the pilot in each frame, it does not need to insert a data symbol and make an assumption between the channel of the frame in which the pilot is located and the channel corresponding to the frame transmitting data in the next frame. The embodiment of the present application improves the practicality and accuracy of channel estimation in the high speed movement scenario.
[0081] In some alternative embodiments, performing delay-time domain symbol detection on the received signal based on the channel-related parameters comprises: Obtaining a symbol estimation result of a delay-Doppler domain according to an input-output relationship between the received signal and a delay-Doppler domain based on a minimum mean squared error (MMSE) linear equalization algorithm; and performing inverse vectorization and demapping on the delay-Doppler domain symbol estimation result to obtain a delay-time domain symbol estimation result.
[0082] Based on equation (5), we obtain: JPEG0007689237000023.jpg8170
[0083] Based on equations (17) and (18), we obtain JPEG0007689237000024.jpg7170
[0084] Further vectorization gives us the following: Here, equation (33) is obtained based on the properties of the Kronecker product, and equation (34) is obtained based on equation (13). By substituting equation (31) into equation (34), equation (35) is obtained. TIFF0007689237000026.tif36170
[0085] Furthermore, by reverse vectorization, we get the following: TIFF0007689237000027.tif11170
[0086] After demapping, we get something like this: TIFF0007689237000028.tif14142
[0087] The resulting delay-time domain symbol estimates are then transformed to the delay-time domain: TIFF0007689237000029.tif12142Further estimate the launch terminal delay-time domain symbols.
[0088] JPEG0007689237000030.jpg23170
[0089] The following provides a symbol detection algorithm based on the MP algorithm in the delay-time domain.
[0090] In some alternative embodiments, performing delay-time domain symbol detection on the received signal based on the channel-related parameters includes:
[0091] Step 5021, based on the input-output relationship of the delay-time domain, obtain a point-to-point input-output relationship in the delay-time domain; Here, point-to-point is discrete sampling point to discrete sampling point.
[0092] Step 5022, based on a Gaussian approximation to the interference term, calculate first information transferred from the factor nodes in the delay-time domain to the variable nodes in the delay-time domain, the first information including the mean and variance of the Gaussian variables; Here, a factor node is composed of a portion of the received sampling points y, a factor node may be called an observation node, and a variable node is composed of a portion of the transmitted sampling points x.
[0093] Step 5023, calculate second information transmitted from the variable nodes to the factor nodes, the second information including the symbol probability masses of the variable nodes; Step 5024, damping the symbol probability mass calculated in the current iteration with the result of the previous iteration; Step 5025, if an iteration stopping condition is met, stop the iteration and perform symbol detection on the variable node, or continue the iteration if an iteration stopping condition is not met.
[0094] In other words, the factor node outputs the "mean value and variance" as input to the variable node, and the variable node outputs the "symbol probability mass" as input to the observation node, and so on. When the values of the "mean value and variance" or "symbol probability mass" satisfy the iteration stopping condition, the loop is exited and subsequent processing is performed using the output of the last loop as the result.
[0095] In a conventional OTFS system, symbols are multiplexed into the delay-Doppler domain, and a factor graph of sparse connectivity is constructed based on the input-output relationship of the delay-Doppler domain. Since the symbols in the embodiment of the present application are multiplexed into the delay-time domain, it is necessary to derive the input-output relationship of the delay-time domain. Based on equation (10), the following is obtained: JPEG0007689237000031.jpg89170
[0096] A point-to-point input-output relationship in the delay-time domain may be described in the form: JPEG0007689237000032.jpg56170
[0097] JPEG0007689237000033.jpg87170
[0098] It should be noted that a probability mass function is for a discrete random variable and corresponds to the symbol probability density of successive sampling points.
[0099] Propagate the probability mass function of the symbol from the variable node to the factor node, and update it as follows: JPEG0007689237000034.jpg19170
[0100] JPEG0007689237000035.jpg28170
[0101] Where: JPEG0007689237000036.jpg16170
[0102] Here, the convergence rate of the iterations is controlled as follows: TIFF0007689237000037.tif17134
[0103] TIFF0007689237000038.tif68170
[0104] Finally, the verdict for each symbol was as follows: As can be seen, in the embodiment of the present application, performing symbol detection of the received signal delay-time domain based on the channel-related parameters includes: Based on the input-output relationship in the delay-time domain, i.e., equation (43), obtaining a point-to-point input-output relationship in the delay-time domain, i.e., equation (44); calculating the information transferred from the factor nodes in the delay-time domain to the variable nodes in this delay-time domain, i.e. the mean value equation (45) and the variance equation (46) of the Gaussian variables, based on a Gaussian approximation to the interference terms; Calculating the information transferred from the variable nodes to the factor nodes based on equations (49) and (52), i.e., the symbol probability masses of the delay-time domain variable nodes; Damping the symbol probability mass calculated in the current iteration based on equation (47) and the result of the previous iteration to improve convergence performance; determining whether an iteration stopping condition is met, and if not, continuing the iteration; if yes, stopping the iteration and performing symbol detection on the variable nodes based on equation (53).
[0105] The embodiments of the present application adopt a symbol detection algorithm based on the MP algorithm in the delay-time domain, adjust the linear operation relationship between the variable node and the factor node according to the input-output relationship in the delay-time domain, and change the symbol detection algorithm based on MP in the delay-Doppler domain (DD domain) to a symbol detection algorithm based on MP in the delay-time domain, thereby reducing the complexity of the equalization time.
[0106] FIG. 6 is a signal processing flow chart according to an embodiment of the present application, in which the pilot pattern design at the transmitting end is carried out first, and then the channel estimation and symbol detection are carried out at the receiving end. It should be mentioned that in the channel transmission method according to the embodiment of the present application, the execution body can be a signal transmission device or a control module for executing the channel transmission method in the signal transmission device. In the embodiment of the present application, the signal transmission device according to the embodiment of the present application is described by taking the signal transmission device executing the channel transmission method as an example.
[0107] FIG. 7 is a structural schematic diagram of a signal transmitting device 700 according to an embodiment of the present application. As shown in FIG. 7, the device includes: a mapping unit 710 and a first processing unit 720, where: The mapping unit 710 is used to map the modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix; The first processing unit 720 is used to perform a first preset processing on the first delay-time domain symbol matrix to obtain time domain sampling points, and transmit them after pulse shaping.
[0108] In the embodiment of the present application, the modulation symbols are mapped into a delay-time domain to obtain a first delay-time domain symbol matrix, a first preset processing is performed on the first delay-time domain symbol matrix to obtain a time domain sampling point, and then pulse shaping is performed before transmission, so that the transmission process reduces the PAPR on the premise of maintaining the characteristics of a single carrier and ensuring the performance of OTFS in high-speed moving scenarios.
[0109] Optionally, the launcher performs a first preset process on the first delay-time domain symbol matrix, performing a discrete Fourier transform (DFT) in a time dimension on the first delay-time domain symbol matrix to obtain a first delay-Doppler domain symbol matrix; performing a Doppler dimension extension on the first delay-Doppler domain symbol matrix to obtain a second delay-Doppler domain symbol matrix; performing an inverse discrete Fourier transform (IDFT) in a Doppler dimension on the second delay-Doppler domain symbol matrix to obtain a second delay-time domain symbol matrix; The method further includes performing a vectorization process on the second delay-time domain symbol matrix to obtain time domain sampling points, and transmitting the time domain sampling points after pulse shaping.
[0110] Optionally, the first processing unit comprises: Dimension is M×N 1 For the first delay-time domain symbol matrix having a length of N 1 The discrete Fourier transform DFT is performed row by row, and the dimensions are M × N 1to obtain a first delay-Doppler domain symbol matrix, where M represents the number of rows of the first delay-time domain symbol matrix, and N 1 represents the number of columns of the first delay-time domain symbol matrix; The dimension is M×N 1 Let the first delay-Doppler domain symbol matrix be of dimension M × N. 2 to a delay-Doppler domain resource grid of dimension M × N 2 obtaining a second delay-Doppler domain symbol matrix, The dimension is M×N 2 For the second delay-Doppler domain symbol matrix with length N 2 The inverse discrete Fourier transform (IDFT) is performed row by row, and the dimensions are M × N 2 obtaining a second delay-time domain symbol matrix, The dimension is M×N 2 A vectorization process is performed on the second delay-time domain symbol matrix, whose length is MN 2 and transmitting the time domain sampling points after pulse shaping the time domain sampling points; Here, N 2 is the number of columns of the symbol matrix in the second delay-Doppler domain, and N 2 is N 1 An integer greater than or equal to .
[0111] Optionally, the first delay-time domain symbol matrix is embedded with a delay-time domain pilot sequence, and the device: N 1 and N 2a demapping unit for demapping the second delay-Doppler domain symbol matrix into the first delay-Doppler domain symbol matrix based on a mapping relationship between and a pilot determining unit for determining a pilot sequence in the delay-time domain based on an inverse discrete Fourier transform relationship between the Doppler domain and the time domain.
[0112] Optionally, the expression of a pilot pattern obtained by mapping the pilot sequence to a delay-time domain resource grid is as follows: JPEG0007689237000040.jpg98170
[0113] In the embodiment of the present application, based on the corresponding relationship between the delay-time domain and the delay-Doppler domain, a pilot pattern design scheme in the delay-time domain is proposed, and channel estimation can be performed in the delay-Doppler domain, which can ensure the accuracy of channel estimation in fractional Doppler shift channels without relying on integer Doppler hypotheses, and reduce the overhead of pilot patterns.
[0114] The signal transmission device in the embodiment of the present application may be a device, a device having an operating system, or an electronic device, and may be a component, an integrated circuit, or a chip in a terminal. The device or electronic device may be a mobile terminal or a non-mobile terminal. Exemplarily, the mobile terminal may include, but is not limited to, the types of terminals 11 listed above, and the non-mobile terminal may be a server, a network attached storage (NAS), a personal computer (PC), a television (TV), a deposit payment machine, or a self-service machine, and the embodiment of the present application is not specifically limited thereto.
[0115] The signal transmitting device according to the embodiment of the present application can realize each process realized by the method embodiments of Figures 2 to 4 and achieve the same technical effects, and will not be further described here to avoid repetition of description.
[0116] It should be noted that the execution body of the channel receiving method according to the embodiment of the present application may be a signal receiving device or a control module for executing the channel receiving method in the signal receiving device. In the embodiment of the present application, the signal receiving device according to the embodiment of the present application is described by taking the signal receiving device executing the channel receiving method as an example.
[0117] FIG. 8 is a structural schematic diagram of a signal receiving device 800 according to an embodiment of the present application. As shown in FIG. 8, the device includes: a second processing unit 810, a channel estimation unit 820 and a symbol detection unit 830, where: The second processing unit 810 is used to perform a second pre-configured processing on the received time-domain signal to obtain a delay-time domain received signal; The channel estimation unit 820 is used to perform channel estimation in the delay-Doppler domain based on the pilot sequence in the delay-time domain to obtain channel-related parameters; The symbol detection unit 830 is used for performing delay-time domain symbol detection on the received signal based on the channel-related parameters.
[0118] In the embodiment of the present application, a second preset processing is performed on the received time-domain signal to obtain a delay-time domain received signal, and channel estimation is performed based on the pilot sequence in the delay-time domain to obtain channel-related parameters, and then delay-time domain symbol detection is performed on the received signal based on the channel-related parameters, thereby reducing the PAPR, improving the accuracy of channel estimation in high-speed moving scenarios, and reducing the overhead of channel estimation, and reducing the complexity of the equalization time of the proposed system.
[0119] Optionally, the delay-time domain pilot sequence is Calculating a pilot sequence in the delay-time domain based on an index value or bitmap information, the index value or bitmap information being indicated by downlink control information (DCI) or radio resource control (RRC) signaling, and the index value or bitmap information being a delay-Doppler domain single-point pilot pulse with a size of M×N 1 expressing a position on the Doppler dimension in a delay-Doppler resource grid as A pilot sequence of the delay-time domain is obtained by querying a pilot index table based on a pilot sequence index, where the pilot sequence index is indicated by DCI or RRC signaling, and the pilot index table is pre-configured by a protocol or indicated by broadcast signaling.
[0120] Optionally, performing a second predetermined processing on the received time domain signal further comprises: de-vectorizing the received time domain signal to obtain a third delay-time domain symbol matrix; performing a discrete Fourier transform (DFT) on the third delay-time domain symbol matrix to obtain a third delay-Doppler domain symbol matrix; Demapping the third delay-Doppler domain symbol matrix to obtain a fourth delay-Doppler domain symbol matrix; and performing an inverse discrete Fourier transform (IDFT) on the fourth delay-Doppler domain symbol matrix row-by-row.
[0121] Optionally, the second processing unit further comprises: Received length is MN 2 Vectorize the time domain signal with dimensions M×N 2 to obtain a third delay-time domain symbol matrix, where M represents the number of rows of the third delay-time domain symbol matrix, and N 2 represents the number of columns of the third delay-time domain symbol matrix; The dimension is M×N 2 A discrete Fourier transform (DFT) is performed on the symbol matrix in the third delay-time domain, 2 obtaining a third delay-Doppler domain symbol matrix, The dimension is M×N 2 Demap the third delay-Doppler domain symbol matrix, 1 obtaining a fourth delay-Doppler domain symbol matrix, The dimension is M×N 1 A row-by-row inverse discrete Fourier transform (IDFT) is performed on the fourth delay-Doppler domain symbol matrix, 1 and obtaining a fourth delay-time domain symbol matrix having a dimension of M×N. 1a fourth delay-time domain symbol matrix, Here, N 1 is the number of columns of the fourth delay-Doppler domain symbol matrix, and N 1 is N 2 The following integers:
[0122] Optionally, the channel estimation unit comprises: calculating an impulse response in a delay-Doppler domain of the delay-time domain pilot sequence within a detection area; performing a correlation calculation on the impulse response and a Doppler function to obtain a first correlation function; performing threshold detection on the amplitude of the first correlation function to obtain a threshold detection result; Based on the threshold detection result, a channel parameter is estimated and a channel-related parameter is obtained.
[0123] Embodiments of the present application improve the practicality and accuracy of channel estimation in high speed mobile scenarios.
[0124] Optionally, the symbol detection unit comprises: obtaining a point-to-point input-output relationship in the delay-time domain based on the input-output relationship in the delay-time domain; Calculating first information to be transferred from factor nodes in the delay-time domain to variable nodes in the delay-time domain based on a Gaussian approximation to an interference term, the first information including a mean and a variance of a Gaussian variable; calculating second information transmitted from the variable nodes to the factor nodes, the second information including symbol probability masses of the variable nodes; a decay control of the symbol probability masses calculated in the current iteration and the results of the previous iteration; It is used to stop the iteration and perform symbol detection on the variable node if the iteration stopping condition is met, or to continue the iteration if the iteration stopping condition is not met.
[0125] Optionally, the symbol detection unit comprises: Obtaining a delay-Doppler domain symbol estimation result according to an input / output relationship between the received signal and a delay-Doppler domain based on an MMSE linear equalization algorithm; The delay-Doppler domain symbol estimation result is subjected to inverse vectorization and demapping to obtain a delay-time domain symbol estimation result.
[0126] The embodiments of the present application adopt a symbol detection algorithm based on the MP algorithm in the delay-time domain, adjust the linear operation relationship between the variable node and the factor node according to the input-output relationship in the delay-time domain, and change the symbol detection algorithm based on MP in the delay-Doppler domain (DD domain) to a symbol detection algorithm based on MP in the delay-time domain, thereby reducing the complexity of the equalization time.
[0127] The signal receiving device in the embodiment of the present application may be a device, a device having an operating system, or an electronic device, and may be a component, an integrated circuit, or a chip in a terminal. The device or electronic device may be a mobile terminal or a non-mobile terminal. Exemplarily, the mobile terminal may include, but is not limited to, the types of terminals 11 listed above, and the non-mobile terminal may be a server, a network attached storage (NAS), a personal computer (PC), a television (TV), a deposit payment machine, or a self-service machine, and the embodiment of the present application is not specifically limited thereto.
[0128] The signal receiving device according to the embodiment of the present application can realize each process realized by the method embodiments of Figures 5 to 6 and achieve the same technical effects, and will not be further described here to avoid repetition of description.
[0129] Optionally, as shown in Fig. 9, an embodiment of the present application further provides a communication device 900, including a processor 901, a memory 902, and a program or instruction stored in the memory 902 and operable on the processor 901, for example, when the communication device 900 is a terminal, when the program or instruction is executed by the processor 901, each process of the embodiment of the channel transmission method or the channel reception method can be realized, and the same technical effect can be achieved. When the communication device 900 is a network side device, when the program or instruction is executed by the processor 901, each process of the embodiment of the channel transmission method or the channel reception method can be realized, and the same technical effect can be achieved. In order to avoid repetition, no further description will be given here.
[0130] The embodiment of the present application further provides a terminal, including a processor and a communication interface, the processor is used for mapping modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix, performing a first preset processing on the first delay-time domain symbol matrix to obtain a time domain sampling point, and transmitting after pulse shaping. Or the processor is used for performing a second preset processing on a received time domain signal to obtain a delay-time domain received signal, performing channel estimation in a delay-Doppler domain based on a pilot sequence in the delay-time domain to obtain a channel-related parameter, and performing delay-time domain symbol detection on the received signal based on the channel-related parameter. The embodiment of the terminal corresponds to the embodiment of the above method, and each implementation process and realization manner of the embodiment of the above method can be applied to the embodiment of the terminal, and the same technical effect can be achieved. Specifically, FIG. 10 is a schematic diagram of a hardware structure for realizing a terminal of the embodiment of the present application.
[0131] The terminal 1000 includes at least some of the following components, but is not limited to: a radio frequency unit 1001, a network module 1002, an audio output unit 1003, an input unit 1004, a sensor 1005, a display unit 1006, a user input unit 1007, an interface unit 1008, a memory 1009, and a processor 1010.
[0132] As can be understood by those skilled in the art, the terminal 1000 may further include a power source (e.g., a battery) for powering each component, and the power source may be logically connected to the processor 1010 by a power management system, so that the power management system can realize functions such as charge / discharge management and power consumption management. The terminal structure shown in FIG. 10 does not constitute a limitation on the terminal, and the terminal may include more or less components than the number of components shown, or a combination of some components, or a different arrangement of components, and will not be further described here.
[0133] It should be understood that in the embodiment of the present application, the input unit 1004 may include a graphics processor (Graphics Processing Unit, GPU) 10041 and a microphone 10042, and the graphics processor 10041 processes image data of still or video images obtained by an image capture device (e.g., a camera) in a video capture mode or an image capture mode. The display unit 1006 may include a display panel 10061, and the display panel 10061 may be configured in the form of a liquid crystal display, an organic light emitting diode, etc. The user input unit 1007 includes a touch panel 10071 and other input devices 10072. The touch panel 10071 is also called a touch screen. The touch panel 10071 may include two parts: a touch detection device and a touch controller. The other input devices 10072 may include, but are not limited to, a physical keyboard, function keys (e.g., volume control buttons, switch buttons, etc.), a trackball, a mouse, and an operation lever, which will not be described further herein.
[0134] In the embodiment of the present application, the radio frequency unit 1001 receives downlink data from the network side device, and then causes the processor 1010 to process the data, and transmits uplink data to the network side device. In general, the radio frequency unit 1001 includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, etc.
[0135] The memory 1009 may be used to store software programs or instructions and various data. The memory 1009 may mainly include a program or instruction storage domain and a data storage domain, where the program or instruction storage domain can store an operating system, an application program or instruction required for at least one function (e.g., a sound playback function, an image playback function, etc.), etc. In addition, the memory 1009 may include a high-speed random access memory, and may include a non-volatile memory, where the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. For example, it may be at least one magnetic disk memory device, a flash memory device, or other non-volatile solid-state memory device.
[0136] The processor 1010 may include one or more processing units. Optionally, the processor 1010 may integrate an application processor and a modem processor, where the application processor mainly processes an operating system, a user interface, and application programs or instructions, and the modem processor mainly processes wireless communication, such as a baseband processor. As can be understood, the modem processor does not have to be integrated into the processor 1010.
[0137] Wherein, the processor 1010 maps the modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix; The first delay-time domain symbol matrix is subjected to a first preset processing to obtain a time domain sampling point, which is then pulse-shaped and then transmitted.
[0138] In the embodiment of the present application, the modulation symbols are mapped into a delay-time domain to obtain a first delay-time domain symbol matrix, a first preset processing is performed on the first delay-time domain symbol matrix to obtain a time domain sampling point, and then pulse shaping is performed before transmission, so that the transmission process reduces the PAPR on the premise of maintaining the characteristics of a single carrier and ensuring the performance of OTFS in high-speed moving scenarios.
[0139] Optionally, the launcher performs a first preset process on the first delay-time domain symbol matrix, performing a discrete Fourier transform (DFT) in a time dimension on the first delay-time domain symbol matrix to obtain a first delay-Doppler domain symbol matrix; performing a Doppler dimension extension on the first delay-Doppler domain symbol matrix to obtain a second delay-Doppler domain symbol matrix; performing an inverse discrete Fourier transform (IDFT) in a Doppler dimension on the second delay-Doppler domain symbol matrix to obtain a second delay-time domain symbol matrix; and performing a vectorization process on the second delay-time domain symbol matrix.
[0140] Optionally, the step of performing a first preset process on the first delay-time domain symbol matrix to obtain time domain sampling points and transmit the time domain sampling points after pulse shaping includes: Dimension is M×N1 For the first delay-time domain symbol matrix having a length of N 1 The discrete Fourier transform DFT is performed row by row, and the dimensions are M × N 1 to obtain a first delay-Doppler domain symbol matrix, where M represents the number of rows of the first delay-time domain symbol matrix, and N 1 represents the number of columns of the first delay-time domain symbol matrix; The dimension is M×N 1 Let the first delay-Doppler domain symbol matrix be of dimension M × N. 2 to a delay-Doppler domain resource grid of dimension M × N 2 obtaining a second delay-Doppler domain symbol matrix, The dimension is M×N 2 For the second delay-Doppler domain symbol matrix with length N 2 The inverse discrete Fourier transform (IDFT) is performed row by row, and the dimensions are M × N 2 obtaining a second delay-time domain symbol matrix, The dimension is M×N 2 A vectorization process is performed on the second delay-time domain symbol matrix, whose length is MN 2 and transmitting the time domain sampling points after pulse shaping the time domain sampling points; Here, N 2 is the number of columns of the symbol matrix in the second delay-Doppler domain, and N 2 is N 1 An integer greater than or equal to .
[0141] Optionally, the first delay-time domain symbol matrix is embedded with a delay-time domain pilot sequence, and the processor 1010 further comprises: N 1 and N 2 Demapping the second delay-Doppler domain symbol matrix into the first delay-Doppler domain symbol matrix based on a mapping relationship between and determining the delay-time domain pilot sequence based on the inverse discrete Fourier transform relationship between the Doppler domain and the time domain.
[0142] Optionally, the expression of a pilot pattern obtained by mapping the pilot sequence to a delay-time domain resource grid is as follows: JPEG0007689237000041.jpg98170
[0143] In the embodiment of the present application, based on the corresponding relationship between the delay-time domain and the delay-Doppler domain, a pilot pattern design scheme in the delay-time domain is proposed, and channel estimation can be performed in the delay-Doppler domain, which can ensure the accuracy of channel estimation in fractional Doppler shift channels without relying on integer Doppler hypotheses, and reduce the overhead of pilot patterns.
[0144] Or, the processor 1010 performing a second predetermined process on the received time domain signal to obtain a delay-time domain received signal; performing channel estimation in a delay-Doppler domain based on a pilot sequence in the delay-time domain to obtain channel-related parameters; The method is used to perform delay-time domain symbol detection on the received signal based on the channel-related parameters.
[0145] In the embodiment of the present application, a second preset processing is performed on the received time-domain signal to obtain a delay-time domain received signal, and channel estimation is performed based on the pilot sequence in the delay-time domain to obtain channel-related parameters, and then delay-time domain symbol detection is performed on the received signal based on the channel-related parameters, thereby reducing the PAPR, improving the accuracy of channel estimation in high-speed moving scenarios, and reducing the overhead of channel estimation, and reducing the complexity of the equalization time of the proposed system.
[0146] Optionally, the delay-time domain pilot sequence is Calculating a pilot sequence in the delay-time domain based on an index value or bitmap information, the index value or bitmap information being indicated by downlink control information (DCI) or radio resource control (RRC) signaling, and the index value or bitmap information being a delay-Doppler domain single-point pilot pulse with a size of M×N 1 expressing a position on the Doppler dimension in a delay-Doppler resource grid as A pilot sequence of the delay-time domain is obtained by querying a pilot index table based on a pilot sequence index, where the pilot sequence index is indicated by DCI or RRC signaling, and the pilot index table is pre-configured by a protocol or indicated by broadcast signaling.
[0147] Optionally, performing a second predetermined processing on the received time domain signal further comprises: de-vectorizing the received time domain signal to obtain a third delay-time domain symbol matrix; performing a discrete Fourier transform (DFT) on the third delay-time domain symbol matrix to obtain a third delay-Doppler domain symbol matrix; Demapping the third delay-Doppler domain symbol matrix to obtain a fourth delay-Doppler domain symbol matrix; and performing an inverse discrete Fourier transform (IDFT) on the fourth delay-Doppler domain symbol matrix row-by-row.
[0148] Optionally, performing a second predetermined process on the received time domain signal to obtain a delay-time domain received signal includes: Received length is MN 2 Vectorize the time domain signal with dimensions M×N 2 to obtain a third delay-time domain symbol matrix, where M represents the number of rows of the third delay-time domain symbol matrix, and N 2 represents the number of columns of the third delay-time domain symbol matrix; The dimension is M×N 2 A discrete Fourier transform (DFT) is performed on the symbol matrix in the third delay-time domain, 2 obtaining a third delay-Doppler domain symbol matrix, The dimension is M×N 2 Demap the third delay-Doppler domain symbol matrix, 1 obtaining a fourth delay-Doppler domain symbol matrix, The dimension is M×N 1 A row-by-row inverse discrete Fourier transform (IDFT) is performed on the fourth delay-Doppler domain symbol matrix, 1and obtaining a fourth delay-time domain symbol matrix having a dimension of M×N. 1 a fourth delay-time domain symbol matrix, Here, N 1 is the number of columns of the fourth delay-Doppler domain symbol matrix, and N 1 is N 2 The following integers:
[0149] Optionally, the step of performing channel estimation in a delay-Doppler domain based on a pilot sequence in a delay-time domain to obtain a channel-related parameter includes: calculating an impulse response in a delay-Doppler domain of the delay-time domain pilot sequence within a detection area; performing a correlation calculation on the impulse response and a Doppler function to obtain a first correlation function; performing threshold detection on the amplitude of the first correlation function to obtain a threshold detection result; and estimating channel parameters based on the threshold detection result to obtain channel-related parameters.
[0150] Optionally, performing delay-time domain symbol detection on the received signal based on the channel-related parameters further comprises: obtaining a point-to-point input-output relationship in the delay-time domain based on the input-output relationship in the delay-time domain; Calculating first information to be transferred from factor nodes in the delay-time domain to variable nodes in the delay-time domain based on a Gaussian approximation to an interference term, the first information including a mean and a variance of a Gaussian variable; calculating second information transmitted from the variable nodes to the factor nodes, the second information including symbol probability masses of the variable nodes; a decay control of the symbol probability masses calculated in the current iteration and the results of the previous iteration; Stopping the iteration and performing symbol detection on the variable nodes if an iteration stopping condition is met, or continuing the iteration if an iteration stopping condition is not met.
[0151] Optionally, performing delay-time domain symbol detection on the received signal based on the channel-related parameters further comprises: Obtaining a delay-Doppler domain symbol estimation result according to an input / output relationship between the received signal and a delay-Doppler domain based on an MMSE linear equalization algorithm; and performing inverse vectorization and demapping on the delay-Doppler domain symbol estimation result to obtain a delay-time domain symbol estimation result.
[0152] The embodiments of the present application adopt a symbol detection algorithm based on the MP algorithm in the delay-time domain, adjust the linear operation relationship between the variable node and the factor node according to the input-output relationship in the delay-time domain, and change the symbol detection algorithm based on MP in the delay-Doppler domain (DD domain) to a symbol detection algorithm based on MP in the delay-time domain, thereby reducing the complexity of the equalization time.
[0153] An embodiment of the present application further provides a network side device, including a processor and a communication interface, the processor is used for mapping modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix, performing a first preset processing on the first delay-time domain symbol matrix to obtain a time domain sampling point, and transmitting after pulse shaping. Or the processor is used for performing a second preset processing on a received time domain signal to obtain a delay-time domain received signal, performing channel estimation in a delay-Doppler domain based on a pilot sequence in the delay-time domain to obtain a channel-related parameter, and performing delay-time domain symbol detection on the received signal based on the channel-related parameter. This embodiment of the network side device corresponds to the embodiment of the above method, and each implementation process and realization manner of the above method embodiment can be applied to this embodiment of the network side device, and the same technical effects can be achieved.
[0154] Specifically, an embodiment of the present application further provides a network side device. As shown in Fig. 11, the network side device 1100 includes an antenna 1101, a radio frequency device 1102, and a baseband device 1103. The antenna 1101 and the radio frequency device 1102 are connected. In the uplink direction, the radio frequency device 1102 receives information through the antenna 1101, and transmits the received information to the baseband device 1103 for processing. In the downlink direction, the baseband device 1103 processes the information to be transmitted and transmits it to the radio frequency device 1102, and the radio frequency device 1102 processes the received information and then sends it out through the antenna 1101.
[0155] The above frequency band processing device may be located in a baseband device 1103, and the method performed by the network side equipment in the above embodiments may be implemented in the baseband device 1103, which includes a processor 1104 and a memory 1105.
[0156] The baseband device 1103 may include, for example, at least one baseband board, on which multiple chips are installed, and as shown in FIG. 11, one of the chips is, for example, a processor 1104, which is connected to a memory 1105, calls a program in the memory 1105, and performs the network side equipment operations shown in the above method embodiments.
[0157] The baseband device 1103 may further include a network interface 1106, which is used to exchange information with the radio frequency device 1102, and this interface is, for example, a common public radio interface (abbreviated as CPRI).
[0158] Specifically, the network side equipment of an embodiment of the present invention further includes instructions or programs stored in memory 1105 and capable of running on processor 1104, and processor 1104 can call instructions or programs in memory 1105 to execute the methods performed by each module shown in FIG. 7 or FIG. 8, and achieve the same technical effects, which will not be described further here in order to avoid repetition.
[0159] The embodiments of the present application further provide a readable storage medium, in which a program or instruction is stored, and when the program or instruction is executed by a processor, each process of the above-mentioned signal transmitting method or signal receiving method embodiment can be realized and the same technical effect can be achieved. In order to avoid repetition, no further description will be given here.
[0160] Wherein, the processor is the processor in the terminal described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.
[0161] The embodiments of the present application further provide a chip, the chip includes a processor and a communication interface, the communication interface is coupled to the processor, the processor is used to run a program or instruction to realize each process of the embodiments of the signal transmitting method or the signal receiving method, and can achieve the same technical effect. In order to avoid repetition, no further description will be given here.
[0162] It should be understood that the chips referred to in the embodiments of the present application may be referred to as system level chips, system chips, chip systems, or systems on chips.
[0163] It should be explained that in this specification, the terms "comprise", "include", or any other variants thereof are intended to cover the non-exclusive "comprise", whereby a process, method, article, or apparatus that includes a set of elements includes not only those elements, but also other elements not expressly listed or inherent to such process, method, article, or apparatus. In the absence of further limitations, an element limited by the phrase "comprises a" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes this element. It should be pointed out that the scope of the method and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may include performing functions in an essentially simultaneous manner or in reverse order based on the functions involved, for example, the described method can be performed in a different order than described, and various steps can be added, omitted, or combined. Also, features described with reference to some examples can be combined in other examples.
[0164] From the above description of the embodiments, it is clear to those skilled in the art that the methods of the above embodiments can be realized in the form of software and a necessary general-purpose hardware platform. Of course, they can also be realized in hardware, but in many cases the former is a more preferred embodiment. In light of this understanding, the technical proposal of the present application may be substantially or the part that contributes to the prior art may be embodied in the form of a computer software product, which is stored in a storage medium (e.g., ROM / RAM, magnetic disk, optical disk) and includes some instructions for causing a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in each embodiment of the present application.
[0165] The above describes the embodiments of the present application in conjunction with the drawings, but the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not limiting. Those skilled in the art can take the suggestions of this application and make many forms without departing from the spirit and scope of the claims of this application, all of which belong to the protection scope of this application.
Claims
1. 1. A method for transmitting a signal, comprising: A launching end maps the modulation symbols in a delay-time domain to obtain a first delay-time domain symbol matrix; The transmitting end performs a first preset processing on the first delay-time domain symbol matrix to obtain a time domain sampling point, and transmits the time domain sampling point after pulse shaping; The launcher performs a first preset process on a symbol matrix of the first delay-time domain, performing a discrete Fourier transform (DFT) in a time dimension on the first delay-time domain symbol matrix to obtain a first delay-Doppler domain symbol matrix; performing a Doppler dimension expansion on the first delay-Doppler domain symbol matrix to obtain a second delay-Doppler domain symbol matrix; performing an inverse discrete Fourier transform (IDFT) in a Doppler dimension on the second delay-Doppler domain symbol matrix to obtain a second delay-time domain symbol matrix; performing a vectorization process on the second delay-time domain symbol matrix to obtain time domain sampling points, and transmitting the time domain sampling points after pulse shaping; Signal transmission method.
2. The step of performing a first preset process on the first delay-time domain symbol matrix to obtain time domain sampling points and transmit the obtained time domain sampling points after pulse shaping includes: Dimension is M x N 1 For the first delay-time domain symbol matrix having a length of N 1 A discrete Fourier transform DFT is performed row by row, and the dimensions are M × N 1 to obtain a first delay-Doppler domain symbol matrix, where M represents the number of rows of the first delay-time domain symbol matrix, and N 1 represents the number of columns of the symbol matrix of the first delay-time domain; The dimension is M×N 1 A first delay-Doppler domain symbol matrix having dimensions M×N 2 and map it to a delay-Doppler domain resource grid with dimensions M×N 2 obtaining a second delay-Doppler domain symbol matrix, The dimension is M×N 2 For a second delay-Doppler domain symbol matrix with length N 2 The inverse discrete Fourier transform (IDFT) is performed row by row, and the dimensions are M × N 2 obtaining a second delay-time domain symbol matrix, The dimension is M×N 2 A vectorization process is performed on the symbol matrix of the second delay-time domain, 2 and transmitting the time domain sampling points after pulse shaping the time domain sampling points; Here, N 2 is the number of columns of the symbol matrix in the second delay-Doppler domain, and N 2 is N 1 The signal transmission method according to claim 1 , wherein the first integer is equal to or greater than the first integer.
3. The first delay-time domain symbol matrix has a delay-time domain pilot sequence embedded therein, and the method includes: N 1 and N 2 Demapping the second delay-Doppler domain symbol matrix into the first delay-Doppler domain symbol matrix based on a mapping relationship between 3. The signal transmission method of claim 2, further comprising: determining a pilot sequence in the delay-time domain based on an inverse discrete Fourier transform relationship between a Doppler domain and a time domain.
4. The expression of the pilot pattern obtained by mapping the pilot sequence to the delay-time domain resource grid is as follows: The signal transmission method according to claim 3.
5. 1. A method for receiving a signal, comprising: The receiving end performs a second preset processing on the received time-domain signal to obtain a delay-time domain received signal; A receiving end performs channel estimation in a delay-Doppler domain according to a pilot sequence in a delay-time domain to obtain channel-related parameters; The receiving end performs delay-time domain symbol detection on the received signal based on the channel-related parameters; performing a second predetermined processing on the received time domain signal, de-vectorizing the received time domain signal to obtain a third delay-time domain symbol matrix; performing a discrete Fourier transform (DFT) on the third delay-time domain symbol matrix to obtain a third delay-Doppler domain symbol matrix; Demapping the third delay-Doppler domain symbol matrix to obtain a fourth delay-Doppler domain symbol matrix; performing an inverse discrete Fourier transform (IDFT) on the fourth delay-Doppler domain symbol matrix row-wise; Signal reception method.
6. The pilot sequence of the delay-time domain is Calculating a pilot sequence of the delay-time domain based on an index value or bitmap information, the index value or bitmap information being indicated by downlink control information (DCI) or radio resource control (RRC) signaling, and the index value or bitmap information being a delay-Doppler domain single-point pilot pulse with a size of M×N 1 expressing a position on the Doppler dimension in a delay-Doppler resource grid where 6. The signal receiving method according to claim 5, further comprising: obtaining a pilot sequence of the delay-time domain by querying a pilot index table based on a pilot sequence index, the pilot sequence index being indicated by DCI or RRC signaling, and the pilot index table being pre-configured by a protocol or indicated by broadcast signaling.
7. performing second predetermined processing on the received time domain signal to obtain a delay-time domain received signal; The received length is MN 2 , which is a time domain signal of dimension M × N 2 and obtaining a third delay-time domain symbol matrix, where M represents the number of rows of the third delay-time domain symbol matrix, and N 2 represents the number of columns of the symbol matrix of the third delay-time domain; The dimension is M×N 2 A discrete Fourier transform (DFT) is performed on a symbol matrix in a third delay-time domain, the symbol matrix having dimensions M×N 2 obtaining a third delay-Doppler domain symbol matrix, The dimension is M×N 2 Demap the third delay-Doppler domain symbol matrix, 1 obtaining a fourth delay-Doppler domain symbol matrix, The dimension is M×N 1 A row-by-row inverse discrete Fourier transform (IDFT) is performed on the fourth delay-Doppler domain symbol matrix, 1 a fourth delay-time domain symbol matrix having a dimension M×N 1 a fourth delay-time domain symbol matrix, Here, N 1 is the number of columns of the fourth delay-Doppler domain symbol matrix, and N 1 is N 2 6. The signal receiving method according to claim 5, wherein:
8. The above-mentioned method of performing channel estimation in the delay-Doppler domain based on the pilot sequence in the delay-time domain to obtain channel-related parameters includes the steps of: calculating an impulse response in a delay-Doppler domain of said delay-time domain pilot sequence within a detection area; performing a correlation calculation on the impulse response and a Doppler function to obtain a first correlation function; performing threshold detection on the amplitude of the first correlation function to obtain a threshold detection result; The method of claim 5, further comprising: estimating channel parameters based on the threshold detection result to obtain channel-related parameters.
9. performing delay-time domain symbol detection on the received signal based on the channel-related parameters, obtaining a point-to-point input-output relationship in the delay-time domain based on the input-output relationship of the delay-time domain; Calculating first information to be transferred from factor nodes in the delay-time domain to variable nodes in the delay-time domain based on a Gaussian approximation to an interference term, the first information including means and variances of Gaussian variables; calculating second information transmitted from the variable nodes to the factor nodes, the second information including symbol probability masses of the variable nodes; a decay control of the symbol probability masses calculated in the current iteration and the results of the previous iteration; The method of claim 5, further comprising: stopping the iteration and performing symbol detection on the variable nodes if an iteration stopping condition is met; or continuing the iteration if an iteration stopping condition is not met.
10. performing delay-time domain symbol detection on the received signal based on the channel-related parameters, Obtaining a delay-Doppler domain symbol estimation result according to an input / output relationship between the received signal and a delay-Doppler domain based on an MMSE linear equalization algorithm; The method of claim 5, further comprising: performing inverse vectorization and demapping on the delay-Doppler domain symbol estimation result to obtain a delay-time domain symbol estimation result.
11. A terminal comprising a processor, a memory, and a program or instructions stored in the memory and operable on the processor, the terminal implementing the steps of a signal transmission method according to any one of claims 1 to 4, or implementing the steps of a signal reception method according to any one of claims 5 to 10, when the program or instructions are executed by the processor.
12. A network side device comprising a processor, a memory, and a program or instructions stored in the memory and operable on the processor, the network side device realizing the steps of a signal transmission method according to any one of claims 1 to 4, or the steps of a signal reception method according to any one of claims 5 to 10, when the program or instructions are executed by the processor.
13. A readable storage medium having a program or instructions stored therein, the program or instructions, when executed by a processor, implementing the steps of a signal transmission method according to any one of claims 1 to 4, or implementing the steps of a signal reception method according to any one of claims 5 to 10.
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