CN115001644A

CN115001644A - Synchronization signal transmission method, device, equipment and storage medium

Info

Publication number: CN115001644A
Application number: CN202110227137.0A
Authority: CN
Inventors: 袁璞; 刘昊
Original assignee: Vivo Mobile Communication Co Ltd
Current assignee: Vivo Mobile Communication Co Ltd
Priority date: 2021-03-01
Filing date: 2021-03-01
Publication date: 2022-09-02
Also published as: WO2022183979A1

Abstract

The application discloses a synchronization signal transmission method, a synchronization signal transmission device, synchronization signal transmission equipment and a storage medium, and belongs to the technical field of communication. The method comprises the following steps: the first communication device generates a synchronization signal sequence mapped in a delay Doppler domain; and transmitting time domain sampling points of the synchronous signal sequence in a delay Doppler domain. According to the embodiment of the application, the synchronous signal sequence is used as the synchronous signal to be transmitted in the delay Doppler domain, so that the good autocorrelation and cross-correlation performance of the synchronous signal is kept, the synchronous detection step of the receiving side is simplified, the method is suitable for the implementation of simplified OTFS engineering, and the extra complexity caused by the fact that the synchronous signal is inserted in the time-frequency domain is avoided.

Description

Synchronization signal transmission method, device, equipment and storage medium

Technical Field

The present application belongs to the field of communication technologies, and in particular, to a synchronization signal transmission method, apparatus, device, and storage medium.

Background

Initial access by the terminal is typically based on a synchronization signal.

The existing synchronization technology is based on an Orthogonal Frequency Division Multiplexing (OFDM) frame structure, that is, OFDM modulation and New Radio (NR) frame structure, and when applied to a synchronization timing function of an Orthogonal Time Frequency Space (OTFS) system, the existing synchronization technology may cause that a device needs to frequently switch a modulation mode between a broadcast channel and a data channel, thereby increasing implementation complexity; in addition, the design that a Primary Synchronization Signal (PSS) -Secondary Synchronization Signal (SSS) binary architecture and a Synchronization Signal (SS) are coupled with a Primary information block (MIB) in a Synchronization Signal Block (SSB) of the existing design are redundant to the OTFS system.

Disclosure of Invention

An object of the embodiments of the present application is to provide a method, an apparatus, a device, and a storage medium for transmitting a synchronization signal, which can simplify a synchronization detection step on a receiving side after the transmission of the synchronization signal.

In a first aspect, a synchronization signal transmission method is provided, and the method includes:

the first communication device generates a synchronization signal sequence mapped in a delay Doppler domain;

the first communication device transmits time domain sampling points of the synchronization signal sequence.

In a second aspect, a synchronization signal transmission method is provided, which includes:

the second communication equipment receives a time domain sampling point of the synchronous signal sequence;

and the second communication equipment carries out synchronous timing detection on the time domain sampling point of the synchronous signal sequence.

In a third aspect, a synchronization signal transmission apparatus is provided, the apparatus including:

a first generating module, configured to generate a synchronization signal sequence mapped in a delay-doppler domain;

and the first transmission module is used for transmitting the time domain sampling points of the synchronous signal sequence.

In a fourth aspect, there is provided a synchronization signal transmission apparatus, including:

the first receiving module is used for receiving time domain sampling points of the synchronous signal sequence;

and the first detection module is used for carrying out synchronous timing detection on the time domain sampling points of the synchronous signal sequence.

In a fifth aspect, a communication device is provided, which comprises a processor, a memory and a program or instructions stored on the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps of the method according to the first aspect.

In a sixth aspect, a communication device is provided, comprising a processor, a memory and a program or instructions stored on the memory and executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the method according to the second aspect.

In a seventh aspect, there is provided a readable storage medium on which a program or instructions are stored, which program or instructions, when executed by a processor, implement the steps of the method according to the first aspect or implement the steps of the method according to the second aspect.

In an eighth aspect, a chip is provided, the chip comprising a processor and a communication interface, the communication interface being coupled to the processor, the processor being configured to execute a program or instructions 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.

In the embodiment of the application, the synchronization signal sequence is used as the synchronization signal to be transmitted in the delayed Doppler domain, so that the good autocorrelation and cross-correlation performance of the synchronization signal is maintained, the synchronization detection step of the receiving side is simplified, the method is suitable for the implementation of the simplified OTFS project, and the extra complexity caused by the insertion of the synchronization signal in the time-frequency domain is avoided.

Drawings

FIG. 1 illustrates a block diagram of a wireless communication system to which embodiments of the present application are applicable;

FIG. 2 is a schematic diagram of the inter-conversion of the delay-Doppler domain and the time-frequency plane provided by the embodiments of the present application;

fig. 3 is a schematic diagram of channel response relationships in different planes according to an embodiment of the present application;

fig. 4 is a schematic diagram of a processing flow of a transceiving end of an OTFS multi-carrier system according to an embodiment of the present application;

fig. 5 is a schematic diagram of pilot resource multiplexing in the delay-doppler domain according to an embodiment of the present application;

fig. 6 is a schematic diagram illustrating detection of a pilot sequence according to an embodiment of the present application;

FIG. 7 is a schematic diagram of a design of a synchronization signal provided in an embodiment of the present application;

fig. 8 is a schematic flowchart of a synchronization signal transmission method provided in an embodiment of the present application, and fig. 9 is a schematic diagram of an engineering implementation of an OTFS system provided in an embodiment of the present application;

FIG. 10 is a schematic diagram of the transformation of a delayed Doppler domain sequence into time domain sample points according to an embodiment of the present application;

FIG. 11 is a diagram illustrating pilot overhead provided by an implementation of the present application;

fig. 12 is a second flowchart illustrating a synchronization signal transmission method according to a second embodiment of the present application;

fig. 13 is a schematic structural diagram of a synchronization signal transmission apparatus according to an embodiment of the present application;

fig. 14 is a second schematic structural diagram of a synchronization signal transmission apparatus according to an embodiment of the present application;

fig. 15 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

fig. 16 is a schematic hardware structure diagram of a terminal provided in an embodiment of the present application;

fig. 17 is a schematic hardware structure diagram of a network-side device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described clearly below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments that can be derived from the embodiments given herein by a person of ordinary skill in the art are intended to be within the scope of the present disclosure.

The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used are interchangeable under appropriate circumstances such that embodiments of the application can be practiced in sequences other than those illustrated or described herein, and the terms "first" and "second" used herein generally do not denote any order, nor do they denote any order, for example, the first object may be one or more. In addition, "and/or" in the specification and the claims means at least one of connected objects, and a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship.

It is noted that the techniques described in the embodiments of the present application are not limited to Long Term Evolution (LTE)/LTE Evolution (LTE-Advanced) systems, but may also be used in 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 often used interchangeably, and the described techniques can be used for both the above-mentioned systems and radio technologies, as well as for other systems and radio technologies. The following description describes a New Radio (NR) system for purposes of example, and NR terminology is used in much of the description below, but the techniques may also be applied to applications other than NR system applications, such as 6th Generation (6G) communication systems.

Fig. 1 shows a block diagram of a wireless communication system to which embodiments of the present application are applicable. The wireless communication system includes a terminal 11 and a network-side device 12. Wherein, the terminal 11 may also be called as a terminal Device or a User Equipment (UE), the terminal 11 may be a Mobile phone, a Tablet Personal Computer (Tablet Personal Computer), a Laptop Computer (Laptop Computer) or a notebook Computer, a Personal Digital Assistant (PDA), a palmtop Computer, a netbook, a super-Mobile Personal Computer (UMPC), a Mobile Internet Device (MID), a Wearable Device (Wearable Device) or a vehicle-mounted Device (VUE), a pedestrian terminal (PUE), and other terminal side devices, the Wearable Device includes: bracelets, earphones, glasses and the like. It should be noted that the embodiment of the present application does not limit the specific type of the terminal 11. The network-side device 12 may be a Base Station or a core network, where the Base Station may be referred to as a node B, an enodeb, 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 node B, an evolved node B (eNB), a home node B, a home enodeb, a WLAN access Point, a WiFi node, a Transmit Receive Point (TRP), or some other suitable term in the field, as long as the same technical effect is achieved, the Base Station is not limited to a specific technical vocabulary, and it should be noted that, in the embodiment of the present application, only the Base Station in the NR system is taken as an example, but the specific type of the Base Station is not limited.

The following describes in detail a synchronization signal transmission method and apparatus provided in the embodiments of the present application with reference to the accompanying drawings.

For convenience of description, the following will be first introduced:

downlink control information, DCI;

a Physical downlink control channel, PDCCH;

a Physical Downlink Shared Channel (PDSCH);

physical resource control, Radio resource control, RRC;

physical broadcast channel, PBCH;

a Master message block, a Master information block, MIB;

system information block, SIB;

resource element, RE;

code division multiplexing, CDM;

orthogonal cover codes, OCC;

mean square error, MSE;

orthogonal frequency division multiplexing, OFDM;

bit error rate, BER;

error rate, Block error rate, BLER;

single frequency network, SFN;

a Synchronization signal block, SSB;

primary synchronization signal, PSS;

secondary synchronization signal, SSS;

demodulation reference signal, DMRS;

discrete Fourier transform, DFT;

fast Fourier transform, FFT;

inverse fast Fourier transform, IFFT;

symplectic Fourier transform, SFFT;

inverse symplectic Fourier transform, ISFFT;

linear feedback shift register, LFSR.

In a complex electromagnetic wave transmission environment in a city, due to the existence of a large number of scattering, reflecting and refracting surfaces, the time when a wireless signal reaches a receiving antenna through different paths is different, namely the multipath effect of transmission. Inter Symbol Interference (ISI) occurs when a preceding symbol and a following symbol of a transmitted signal arrive at the same time via different paths, or when the following symbol arrives within the delay spread of the preceding symbol. Similarly, in the frequency domain, due to the doppler effect caused by the relative speed of the transmitting and receiving ends, the sub-carriers in which the signals are located will generate frequency offsets of different degrees, so that the sub-carriers that may be orthogonal originally overlap, i.e. inter-carrier interference (ICI) is generated. An Orthogonal Frequency Division Multiplexing (OFDM) multicarrier system used in a communication system has a better performance of ISI resistance by adding a Cyclic Prefix (CP) design. However, OFDM has a weak point that the size of the subcarrier spacing is limited, so that in a high-speed mobile scenario (such as high-speed rail), due to a large doppler shift caused by a large relative speed between the transmitting and receiving ends, orthogonality between OFDM subcarriers is destroyed, and severe ICI is generated between subcarriers.

The Orthogonal Time Frequency Space (OTFS) technique is proposed to solve the above problem in the OFDM system. The OTFS technique defines a transform between the delay-doppler domain and the time-frequency domain. The service data and the pilot frequency are mapped to the delay Doppler domain at the receiving and transmitting end for processing, the delay and Doppler characteristics of the channel are captured by designing the pilot frequency in the delay Doppler domain, and the problem of pilot frequency pollution caused by ICI in an OFDM system is avoided by designing the guard interval, so that the channel estimation is more accurate, and the receiving end is favorable for improving the success rate of data decoding.

In the OTFS technique, a guard interval is required around a pilot symbol located in a delay-doppler domain, and the size of the guard interval is related to channel characteristics. According to the method and the device, the size of the pilot symbol guard interval is dynamically adjusted according to the channel characteristics through measuring the channel, so that the pilot overhead is approximately minimized on the premise of meeting the system design, and the problem of resource waste caused by always considering the worst condition in the traditional scheme is avoided.

The delay and doppler characteristics of the channel are essentially determined by the multipath channel. The signals arriving at the receiving end through different paths have different arrival times because of the difference of propagation paths. For example two echoes s ₁ And s ₂ Each over a distance d ₁ And d ₂ When they arrive at the receiving end, the time difference of their arrival at the receiving end is:

where c is the speed of light.

Due to the echo s ₁ And s ₂ Between areThis time difference, coherent superposition of which on the receiving side, causes the observed signal amplitude jitter, i.e. fading effects. Similarly, the doppler spread of a multipath channel is also due to multipath effects.

The doppler effect is that because of the relative speed at the two transmitting and receiving ends, the incident angles of the signals arriving at the receiving end through different paths are different from the normal of the antenna, so that the relative speed difference is caused, and the doppler frequency shifts of the signals of different paths are different. Assume that the original frequency of the signal is f ₀ The relative speed of the receiving and transmitting end is Δ v, and the normal incidence angle between the signal and the receiving end antenna is θ. Then there are:

obviously, when two echoes s ₁ And s ₂ Reach the receiving end antenna through different paths and have different incident angles theta ₁ And theta ₂ Their resulting doppler shift Δ f ₁ And Δ f ₂ And also different.

In summary, the signal received by the receiving end is a superposition of component signals from different paths and having different delays and dopplers, and is integrally embodied as a received signal having fading and frequency shift relative to the original signal. And performing delay-doppler analysis on the channel helps to collect delay-doppler information for each path, thereby reflecting the delay-doppler response of the channel.

The OTFS modulation technique is known as orthogonal time-frequency-space modulation. The technique logically maps information in an M × N packet, such as Quadrature Amplitude Modulation (QAM) symbols, to an M × N lattice on a two-dimensional delay-doppler domain, i.e., the pulses within each lattice modulate a QAM symbol in the packet.

Fig. 2 is a schematic diagram of the interconversion between the delay-doppler domain and the time-frequency plane provided by the embodiment of the present application, and as shown in fig. 2, the data set on the M × N delay-doppler domain plane is transformed onto the N × M time-frequency domain plane by designing a set of orthogonal two-dimensional basis functions, and this transformation is mathematically called Inverse symplectic Fourier Transform (ISFFT). Correspondingly, the transformation from the time-frequency domain to the delay-doppler domain is called symplectic Fourier Transform (sympleic Fourier Transform). The physical meaning behind this is the delay and doppler effect of the signal, which is in fact a linear superposition of a series of echoes with different time and frequency offsets after the signal has passed through the multipath channel. In this sense, the delay-doppler analysis and the time-frequency domain analysis can be obtained by the said ISFFT and SSFT interconversion.

Thus, the OTFS technology transforms a time-varying multipath channel into a time-invariant two-dimensional delay-doppler domain channel (within a certain duration), thereby directly reflecting the channel delay-doppler response characteristics in a wireless link due to the geometrical characteristics of the relative positions of reflectors between transceivers. The advantage of this is that OTFS eliminates the difficulty of tracking time-varying fading characteristics in the conventional time-frequency domain analysis, and instead extracts all diversity characteristics of the time-frequency domain channel through delay-doppler domain analysis. In an actual system, because the number of delay paths and doppler shifts of a channel is far smaller than the number of time-domain and frequency-domain responses of the channel, a channel impulse response matrix characterized by a delay doppler domain has sparsity. The OTFS technology is utilized to analyze the sparse channel matrix in the delay Doppler domain, so that the reference signal can be more tightly and flexibly packaged, and the method is particularly favorable for supporting a large-scale antenna array in a large-scale MIMO system.

The core of the OTFS modulation is that QAM symbols defined on a delay Doppler domain are transformed to a time-frequency domain for transmission, and then a receiving end returns to the delay Doppler domain for processing. A wireless channel response analysis method on the delay-doppler domain can be introduced.

Fig. 3 is a schematic diagram of a relationship of channel responses in different planes according to an embodiment of the present application, and fig. 3 shows a relationship between expressions of channel responses in different planes when a signal passes through a linear time-varying wireless channel.

In fig. 3, the SFFT transform formula is:

h(τ,v)＝∫∫H(t,f)e ^{-j2π(vt-fτ)} dτdv； (1)

correspondingly, the transform formula of the ISFFT is:

H(t,f)＝∫∫h(τ,v)e ^j2π(vt-fτ) dτdv； (2)

when the signal passes through the linear time-varying channel, let the time domain received signal be r (t), its corresponding frequency domain received signal be R (f), and there are

r (t) can be expressed as follows:

r(t)＝s(t)*h(t)＝∫g(t,τ)s(t-τ)dv； (3)

as can be seen from the relationship of figure 3,

g(t,τ)＝∫h(v,τ)e ^j2πvt dv； (4)

substituting (4) into (3) can obtain:

r(t)＝∫∫h(v,τ)s(t-τ)e ^j2πvt dτdv； (5)

from the relationship shown in fig. 3, the classical fourier transform theory, and equation (5):

equation (6) suggests that the delay-doppler domain analysis in the OTFS system can be implemented by adding an additional signal processing procedure at the transmitting and receiving ends by relying on the existing communication framework established on the time-frequency domain. In addition, the additional signal processing only consists of Fourier transform, and can be completely realized by the existing hardware without adding a module. The good compatibility with the existing hardware system greatly facilitates the application of the OTFS system. In an actual system, the OTFS technology can be conveniently implemented as a pre-processing module and a post-processing module of a filtering OFDM system, and thus has good compatibility with the existing multi-carrier system.

When the OTFS is combined with the multi-carrier system, the implementation manner of the sending end is as follows: QAM symbols containing information to be transmitted are carried by a waveform in a delay doppler domain, converted into a waveform in a time-frequency domain plane in a conventional multicarrier system through two-dimensional Inverse Fourier Transform (ISFFT), and then converted into time-domain sampling points through symbol-level one-dimensional Inverse Fast Fourier Transform (IFFT) and serial-parallel conversion.

The receiving end of the OTFS system is roughly the inverse process of the sending end: after a time domain sampling point is received by a receiving end, the time domain sampling point is converted and subjected to one-dimensional Fast Fourier Transform (FFT) at a symbol level, the time domain sampling point is firstly converted into a waveform on a time-frequency domain plane, then the time domain sampling point is converted into a waveform on a delay doppler domain plane through two-dimensional Fourier Transform (SFFT), and then the receiving end is used for processing a QAM symbol carried by the delay doppler domain waveform: including but not limited to channel estimation and equalization, demodulation and decoding, etc.

Fig. 4 is a schematic diagram of a processing flow at a transceiving end of an OTFS multi-carrier system according to an embodiment of the present application.

The advantages of OTFS modulation are mainly reflected in the following aspects:

1) OTFS modulation transforms a time-varying fading channel in the time-frequency domain between transceivers into a deterministic fading-free channel in the delay-doppler domain. In the delay-doppler domain, each symbol in a group of information symbols transmitted at a time experiences the same static channel response and SNR.

2) OTFS systems resolve reflectors in the physical channel by delaying the doppler image and coherently combine the energy from different reflected paths with a receive equalizer, providing in effect a static channel response without fading. By utilizing the static channel characteristics, the OTFS system does not need to introduce closed-loop channel self-adaptation to deal with the fast-changing channel like an OFDM system, thereby improving the robustness of the system and reducing the complexity of the system design.

3) Since the number of delay-doppler states in the delay-doppler domain is much smaller than the number of time-frequency states in the time-frequency domain, the channel in the OTFS system can be expressed in a very compact form. The channel estimation overhead of the OTFS system is less and more accurate.

4) Another advantageous implementation of OTFS should be on the extreme doppler channel. By analyzing the delay Doppler image under proper signal processing parameters, the Doppler characteristics of the channel can be completely presented, thereby being beneficial to signal analysis and processing under Doppler sensitive scenes (such as high-speed movement and millimeter waves).

Based on the above analysis, a completely new method can be adopted for channel estimation in the OTFS system. The transmitter maps the pilot frequency pulse on the delay Doppler domain, and the receiving end estimates the channel response h (v, tau) of the delay Doppler domain by analyzing the delay Doppler image of the pilot frequency, so that a channel response expression of the time-frequency domain can be obtained according to the relation shown in FIG. 3, and the signal analysis and processing can be conveniently carried out by applying the prior art of the time-frequency domain.

Fig. 5 is a schematic diagram of pilot resource multiplexing in the delay-doppler domain according to an embodiment of the present application; as shown in fig. 5, the pilot is a pilot sequence constructed based on a PN (pseudo random) sequence generated in a specific manner, and is mapped on a two-dimensional resource grid on the delay doppler plane according to a specific rule, i.e., a hatched portion of the diagonal lines in the figure. In this application, the resource position occupied by the pilot sequence, i.e. the diagonally shaded portion, may be referred to as a pilot resource block. The unshaded area next to the pilot resource block is a pilot guard band, consisting of blank resource elements that do not send any signals/data. Similar to the single-point pilot, a guard band is also provided around its periphery to avoid interference with data. The calculation method of the guard band width is the same as that in the single-point pilot mapping mode of fig. 5. The difference is that in the resource part mapped by the pilot sequence, the pilot signals of different ports can be generated by selecting a sequence with low correlation, the pilot signals are superposed and mapped on the same resource, and then the pilot sequence is detected at the receiving end through a specific algorithm, so as to distinguish the pilots corresponding to different antenna ports. Due to the fact that complete resource multiplexing is carried out at the sending end, pilot frequency overhead under the multi-antenna port system can be greatly reduced.

Fig. 6 is a schematic diagram of detecting a pilot sequence according to an embodiment of the present application, and as shown in fig. 6, a detection manner based on a sequence pilot is presented. At the receivingOn the other hand, due to the different delays and doppler shifts of the two paths of the channel, the received pilot signal block is shifted in the delay-doppler direction to the block position of the hatched portion (i.e., the block numbered 2 and the 8 blocks adjacent to the block, and the block numbered 3 and the 8 blocks adjacent to the block) in the figure. At this time, the sliding window detection operation is performed in the delayed Doppler domain by using the known transmitted pilot (the cross-hatched portion in the figure, i.e. the block marked with 1 and the 8 adjacent blocks). The sliding window detection operation result M (R, S) [ delta, omega ] is known]In N _P On "→ + ∞", the following property is exhibited (the probability of the following equation being established approaches 1):

wherein

C > 0 is a constant.

In the formula (delta, omega) and (delta) ₀ ,ω ₀ ) The current (center point) position of the sliding window and the position to which the pilot signal block (center point) in the received signal is shifted are respectively. As can be seen from the formula, only when (δ, ω) is (δ ═ δ ₀ ,ω ₀ ) A value around 1 can only be obtained, whereas the sliding window detection operation results in a smaller value. Thus, when the sliding window (hatched by lines, i.e. the block marked 1 and the 8 blocks adjacent to the block) coincides with the shifted pilot signal block (hatched by lines, i.e. the block marked 2 and the 8 blocks adjacent to the block, and the block marked 3 and the 8 blocks adjacent to the block), the detection opportunity calculates an energy peak, which is present in the delayed Doppler domain (delta) ₀ ,ω ₀ ) The positions of the small squares numbered 2 and 3 in the figure. By this method, as long as N is guaranteed _P With sufficient length, the receiving end can obtain the correct pilot position according to the value of M (R, S), i.e. obtain the delay and doppler information of the channel. At the same time, the user can select the desired position,amplitude values of the channel being obtained by detection operations

The values are given.

In the delay-doppler domain, a general method of constructing a pilot (or reference signal) sequence is as follows. First, a base sequence is generated. The base sequence may employ a ZC sequence or a PN sequence. Wherein the PN sequence comprises the following sequences: m sequence, Gold sequence, Kasami sequence, Barker sequence, etc. Then, the base sequence is modulated to generate a pilot sequence. Optionally, OCC may be used for the pilot sequence to further improve orthogonality.

Fig. 7 is a schematic diagram of a synchronization signal design provided in an embodiment of the present application, and as shown in fig. 7, initial access of both LTE and NR is performed by relying on synchronization signals (including PSS and SSS), where PSS is a primary synchronization signal used for finding a frame boundary (timing synchronization). SSS is a secondary synchronization signal, indicating Cell ID with PSS. The PBCH is a physical broadcast channel, in which MIB messages and DMRS convey the most important part of system messages for subsequent random access and data transmission.

The architecture of the initial access technology in NR is mainly based on the design development of SSB. The base station periodically transmits the SSBs for initial access according to a rule set by a protocol (e.g., time-frequency domain resource location, transmission period, synchronization signal generation method, etc.). The main process is as follows:

1) initial network searching: including SSB synchronization and reception of system information. Specifically, the primary synchronization information PSS may be received first, the secondary synchronization information SSS may be received, and the PBCH may be received: and acquiring the SSB index, and information in the PBCH DMRS and the MIB.

2) And receiving broadcasted System Information (SI) according to the acquired information, wherein the SI includes information required for accessing the system.

3) And carrying out random access according to the obtained information required by the system access.

The above is the initial access procedure in the NR single base station cell. The UE accepts only the SSB from the current cell, acquires system information by detecting synchronization signals (including PSS and SSS) in the SSB, and reference signals (DMRS) and data information (MIB) in the PBCH, and thereby performs further random access by transmitting an uplink message. In the above procedure, the pilots (PSS and SSS) used for synchronization are tightly coupled to the data part (content in PBCH) that implies the system messages.

In the above initial access procedure, the detection of the primary synchronization signal and the PSS, which is required to be performed first, includes:

1) the base station periodically transmits the SSB for initial access according to the principle set by the protocol (such as time-frequency domain resource position, transmission period, synchronization signal generation mode, etc.)

2) In the initial access stage, the UE does not have prior information of the frame timing boundary, so the UE needs to perform sliding window detection on the received time domain sampling point according to the SSB mapping and sending rules defined by the protocol. Specifically, the method comprises the following steps:

1) the UE buffers a sufficiently long time-domain sample point.

2) The UE generates local time domain sampling points for detection according to the synchronous signal sequence determined by the protocol

3) And the UE defines a sliding detection window and slides on the cached time domain sampling points sample by sample. And when one sampling point slides, performing correlation operation on the current cache time domain sampling point in the sliding detection window and the local time domain sampling point to obtain a correlation peak value.

4) After the sliding window traverses all the cached time domain sampling points, a group of correlation peak values are obtained. And finding the position of the sliding window corresponding to the maximum correlation peak value on the time domain sampling point of the buffer memory, namely finding the position of the synchronous signal on the time domain sampling point.

5) According to the frame structure defined by the protocol, namely the mapping position of the synchronous signal in the sub-frame/time slot, we can deduce where the frame boundary is, namely realize the synchronous timing.

Fig. 8 is a schematic flowchart of a synchronization signal transmission method according to an embodiment of the present application, and as shown in fig. 8, the method includes the following steps:

step 800, the first communication device generates a synchronization signal sequence mapped in a delay Doppler domain;

step 810, the first communication device transmits the time domain sampling point of the synchronization signal sequence.

Optionally, the embodiment of the present application may be applied to a downlink, where the first communication device may be a network side device, such as a base station, and at this time, a communication peer thereof, that is, the second communication device may be a terminal UE.

Optionally, the embodiment of the present application may be applied to a sidelink, where the first communication device may be a terminal UE, and at this time, a communication peer thereof, that is, the second communication device may be a terminal UE.

Optionally, in this embodiment of the present application, the first communication device may be referred to as a sending end, and the second communication device may be referred to as a receiving end.

Optionally, the first communication device may employ a sequence-based synchronization signal sequence for OTFS modulation.

Alternatively, the synchronization signal sequence is generated based on a sequence with good auto-correlation and cross-correlation performance, and after modulating the synchronization signal sequence, the first communication device may map the synchronization signal sequence onto a delay-doppler domain resource grid, and then convert the synchronization signal sequence from the delay-doppler domain to the time domain for transmission.

Alternatively, the synchronization signal sequence is transmitted through a pilot frame.

Optionally, after the synchronization signal sequence is processed by the OTFS system baseband and changed into the transmitted time-domain sampling point, good auto-correlation and cross-correlation performance can still be maintained. Therefore, the second communication device, i.e., the receiving end, can directly detect the synchronization signal based on the received time domain sampling point, and acquire the synchronization timing without an additional processing step.

FIG. 9 is a schematic diagram of an engineering implementation of an OTFS system provided by an embodiment of the present application; as shown in fig. 9, the left half is the complete flow of OTFS baseband processing, and the right half is the simplified flow of OTFS baseband processing. Taking fig. 9 as an example, in the complete flow, the data set X mapped on a 2048 × 128 delay doppler resource grid needs to undergo an ISFFT transform into the time-frequency domain, where the ISFFT consists of 2048-point FFT performed on each column of elements and 128-point IFFT performed on each row of elements. To obtainData set X of time-frequency domain _TF 。

Alternatively, X _TF The matrix expression of (a) is:

wherein F _N The DFT operator in the form of matrix, the left multiplication means that DFT is carried out on the matrix row by row, and the right multiplication means that DFT is carried out on the matrix column by column. X _TF When the time domain sampling point is sent, the conversion process needs to be converted into a time domain sampling point, namely the Heisenberg transform in FIG. 9. For a specific operation, to X _TF Performing 2048-point IFFT operation on each column, and then performing shaping filtering column by column to obtain a processed matrix S. And quantizing the S to obtain the sent time domain sampling point.

Optionally, the matrix expression of S is:

therefore, a simple input-output relationship between the actually transmitted time domain pulse sequence S and the delay Doppler domain data set X can be obtained. From this relationship, the actual engineering implementation can be simplified to the right half of fig. 9. Namely, the data set X is processed with 128-point IFFT row by row, then shaped and filtered column by column, and sent after vectorization.

Optionally, an embodiment of the present application provides a design scheme of a synchronization signal in a delay-doppler domain in an OTFS modulation system, where the design scheme is used for initial access of a UE.

Optionally, in the embodiment of the present application, a dedicated synchronization mechanism is designed for OTFS modulation, so as to better utilize the advantages of the OTFS system.

According to the method and the device, the synchronization signal sequence is adopted as the synchronization signal to be transmitted in the delay Doppler domain, so that the good self-correlation and cross-correlation performance of the synchronization signal is kept, the synchronization detection step of the receiving side is simplified, the method and the device are suitable for the realization of simplified OTFS engineering, and the extra complexity caused by the insertion of the synchronization signal in the time-frequency domain is avoided.

Optionally, the generating a synchronization signal sequence mapped in a delay-doppler domain includes:

not reserving guard bands for the synchronization signal sequences on a resource grid of the delay-Doppler domain; or reserving a guard band for the synchronization signal sequence on a resource grid of the delay-Doppler domain.

in case the synchronization signal sequence is only used for synchronization timing, no guard band is reserved for the synchronization signal sequence on the resource grid of the delay-doppler domain.

Alternatively, in the case that the synchronization signal sequence is only used for synchronization timing, that is, the pilot frame in which the synchronization signal is located only contains the pilot and is only used for finding the synchronization timing, that is, the receiving side does not need to use the pilot to perform (delay doppler domain) channel estimation. There is no need to reserve guard bands for the mapping of the synchronization signal sequences.

Alternatively, since the guard band may not need to be considered, more pilot symbols may be placed in the same size of resource, thereby enhancing detection performance; some information bits are additionally carried with pilot sequence combinations.

in case the synchronization signal sequence is used for synchronization timing and for obtaining channel quality related information, a guard band is reserved for the synchronization signal sequence on a resource grid of the delay-doppler domain.

Optionally, in the case that the synchronization signal sequence is used for synchronization timing and for acquiring channel quality related information, that is, the pilot frame in which the synchronization signal is located only contains pilots, and enough guard bands are reserved in both delay and doppler dimensions for channel estimation, a function similar to that of CSI-RS in NR is provided.

Alternatively, after finding the frame timing based on the synchronization signal sequence, channel estimation may be further performed, thereby acquiring CSI.

and reserving a guard band between a resource grid mapped by the synchronization signal sequence and a resource grid mapped by the data signal under the condition that the synchronization signal sequence is used for synchronizing timing and acquiring the channel quality related information and the pilot frame in which the synchronization signal sequence is positioned comprises the data signal.

Optionally, when the synchronization signal sequence is used for synchronizing timing and acquiring channel quality related information, and a pilot frame in which the synchronization signal sequence is located includes a data signal, that is, the pilot frame in which the synchronization signal is located includes both a pilot and data (similar to a system message in an SSB of NR).

Alternatively, after finding the frame timing based on the synchronization signal sequence, channel estimation may be further performed, thereby acquiring CSI. And demodulating the data part according to the obtained CSI to obtain system information.

Alternatively, the receiving side may first detect the frame timing using the pilot (synchronization signal sequence), and then further perform channel estimation in the delay-doppler domain using the pilot for demodulating the data portion. A guard band needs to be reserved between the pilot and data, and the data is distributed over C delay taps and D Doppler taps. The sizes of C and D mainly depend on the size of the data sampling point needing to be sent; for example, if the number of information bits to be transmitted is N, the selected code rate is a, and the selected modulation order is M-QAM, the number of samples to be transmitted is K — N/a/log _2 (M). The K QAM symbols can be mapped onto the delay-doppler domain, K ═ C × D.

Alternatively, delay tap may refer to a delay tap, i.e., a delay dimension coordinate of a delay doppler resource grid.

Alternatively, delay tap may refer to the delay dimension coordinate of some or all of the delay doppler resource bins in one doppler dimension coordinate.

Alternatively, the pilot frame may carry multiple functions: acquiring timing synchronization; obtaining accurate CSI; and serving user data demodulation in subsequent time slots (using QCL relationships); pilot resources for subsequent time slots are adapted; and after synchronous timing, recovering a delay Doppler domain resource grid, and utilizing the pilot frequency to carry out channel estimation so as to demodulate data in the frame.

and determining a resource grid mode of the synchronization signal sequence mapped to a delay Doppler domain based on the channel quality related information.

Optionally, in a case where the first communication device acquires channel quality related information, a resource grid pattern of the synchronization signal sequence mapped to a delay-doppler domain may be determined based on the channel quality related information.

Optionally, since the ISFFT operation in the OTFS baseband processing is equivalent to a two-dimensional spreading operation performed on the signal by using a DFT operator, the number of samples carrying information is increased, and thus the complexity of the receiving end detection is increased. Therefore, aiming at the characteristic of OTFS baseband signal processing, by designing a special pattern of signals mapped in a delay Doppler domain, the effect of reducing the complexity of receiver sequence detection can be achieved, and the popularization and application of the technology are facilitated.

Alternatively, a pilot sequence X may be defined on an mxn delay doppler plane for synchronization detection. The distribution of time domain sample points containing the X sequence information has a corresponding relationship with the mapping of X on the delay doppler domain.

Fig. 10 is a schematic diagram of transforming the delayed doppler domain sequence into the time domain sampling point according to the embodiment of the present application, and as shown in fig. 10, the process of transforming the delayed doppler domain sequence into the time domain sampling point is performed in two mapping manners.

Optionally, the mapping manner one: the baseband processing process is to perform IFFT on the delay doppler domain data set row by row, so that the pilot frequency X can be mapped onto the delay doppler domain plane with size of M × N row by row, that is, only onto the row corresponding to a certain delay tap, and after being converted into the delay-time domain, only the information of the pilot frequency X on the certain delay tap is recorded as X _dt And X _dt Is N. Acquired time domain acquisition after warp quantizationOn a sample point, is embodied as X _dt Evenly distributed at regular intervals over the MN × 1 transmission sample points, as shown on the left side of fig. 10.

Optionally, the mapping manner two: when the pilot frequency X is mapped on the delay Doppler plane in columns, namely only mapped on the column corresponding to a certain Doppler tap, after the progressive IFFT, the information is spread to all the sampling points of a plurality of delay taps on the delay-time domain, and the sampling points are marked as X _dt . In the extreme case shown on the right side of FIG. 10, the information for X is spread across all samples at M delay taps, i.e., X _dt Distributed over all time-domain sample points obtained after vectorization, at which time X _dt Is MN.

Optionally, when the mapping mode is one, the receiving side only needs to extract a small number of sampling points at a proper position for detection when detecting the number of received sampling points; when the mapping method two is adopted, the receiving side needs to detect more sampling points.

Alternatively, if the mapping of the pilot frequency X in the delay-doppler domain only exists on Q delay taps, the number of sampling points that the receiving side needs to detect is QN. And the sampling point interval of the sampling points at the receiving side is M-Q.

Alternatively, assuming that the origin of coordinates in the delayed doppler domain is the vertex of the upper left corner of the resource grid in the delayed doppler domain, the pilot X may be mapped from the pth delay tap, and then X _dt The starting position appearing in MN × 1 time-domain sample points of the current time slot is P.

Alternatively, when the pilot mapping is known, the receiver side can obtain X _dt Prior information on the location of the received time-domain sample points, i.e. X _dt Coordinate positions in all time domain sampling points of the current time slot are as follows:

[P,P+(M-Q+1),…,P+(N-1)(M-Q+1)]；

in addition, the overhead of pilot design is considered, which includes the overhead of the pilot sequence itself and the overhead of the pilot sequence guard band.

Fig. 11 is a schematic diagram of pilot overhead provided in the present application, and as shown in fig. 11, the pilots may be mapped on a resource grid of the delay-doppler domain by a rectangular pattern, and only the pilots exist on the resource grid and do not include data.

Optionally, the total length of the pilot is L, and the pilot exists in Q delay taps, it is easy to know that the pilot exists in

And at Doppler tap. Assuming that the width of the pilot guard band in the delay dimension is a and the width in the Doppler dimension is B, the total overhead of the pilot is:

therefore, minimizing the pilot overhead is equivalent to solving the minimization problem as follows:

therefore, the currently optimized pilot mapping can be determined, that is:

wherein Q is the side length of the mapped resource block;

alternatively, since the number of samples to be detected at the receiver side is QN,

round down to X _dt The receiver side detection complexity can be reduced by occupying as few delay taps as possible.

Alternatively, it may be that when the first communication device, such as a base station, has a priori information of the channel, i.e. (τ) _max ,v _max ) (A, B) can be determined on the basis of this, and then countedAnd calculating better Q and determining the mapping mode of the pilot signal.

For example, when the first communications device is a base station, it may be when the base station has a priori information of the channel, i.e. (τ) _max ,v _max ) Then, (a, B) can be determined first, so as to calculate the better Q, and determine the mapping mode of the pilot signal.

Alternatively, only the pilot is contained in the pilot frame and used only to find the synchronization timing, i.e. the receiver side does not need to use the pilot for (delay-doppler domain) channel estimation. So that no guard band needs to be reserved. The design criteria of the pilot mapping scheme are as follows:

alternatively, both pilot (synchronization signal sequence) and data (similar to the system message in the NR's SSB) are contained in the pilot frame used for synchronization. The receiving side can detect the frame timing using the pilot and then further perform channel estimation in the delay-doppler domain using the pilot for demodulation of the data portion. A guard band needs to be reserved between the pilot and data, and the data is distributed over C delay taps and D Doppler taps. Accordingly, minimizing pilot overhead is equivalent to solving a minimization problem,

wherein, the first and the second end of the pipe are connected with each other,

optionally, the determining, based on the channel quality related information, a resource grid pattern of the synchronization signal sequence mapped to a delay-doppler domain includes:

determining a resource grid mode of the synchronization signal sequence mapped to a delay Doppler domain based on one piece of recently acquired channel quality related information; or

Determining a resource grid mode of the synchronization signal sequence mapped to a delay Doppler domain based on the maximum channel quality related information in the obtained at least two pieces of channel quality related information; or

And determining a resource grid pattern of the synchronization signal sequence mapped to a delay Doppler domain based on the average value of the obtained at least two pieces of channel quality related information.

Optionally, when determining the resource grid pattern mapped to the delay-doppler domain by the synchronization signal sequence based on the channel quality related information, the first communication device may determine the resource grid pattern mapped to the delay-doppler domain by the synchronization signal sequence based on a most recently acquired channel quality related information.

For example, (tau) measured using the kth synchronization pilot _max ,v _max ) And determining the size of a pilot guard band used by the k < th > to the (k +1) th pilot frames, namely calculating Q.

Optionally, when determining that the synchronization signal sequence is mapped to the resource grid pattern of the delay doppler domain based on the channel quality related information, the first communication device may determine that the synchronization signal sequence is mapped to the resource grid pattern of the delay doppler domain based on the largest channel quality related information of the obtained at least two pieces of channel quality related information;

for example, several sets (τ) of simultaneous pilot measurements can be made in succession _max ,v _max ) Then, based on the maximum value, the resource grid pattern of the synchronization signal sequence mapped to the delay-doppler domain is determined, i.e. Q is calculated.

Optionally, when determining the resource grid pattern mapped to the delay-doppler domain by the synchronization signal sequence based on the channel quality related information, the first communication device may determine the resource grid pattern mapped to the delay-doppler domain by the synchronization signal sequence based on an average value of at least two obtained channel quality related information.

For example, canIn groups (tau) measured on a plurality of consecutive synchronisation pilots _max ,v _max ) Taking an average value, and determining a resource grid pattern of the synchronization signal sequence mapped to the delay-doppler domain based on the average value, namely calculating Q.

Optionally, in this embodiment of the present application, information about signal quality obtained after performing channel estimation on one or more pilots (e.g., synchronization signal sequences) may be used for pilot resource adaptation in a subsequent time slot, for example, as a priori knowledge, the first communication device determines a pilot mapping pattern; i.e. using the maximum delay and maximum doppler information in the CSI information, i.e. (τ) _max ,v _max ) And determining a pilot guard band mode in the subsequent time slot.

Alternatively, the guard band pattern may include the size of the guard band and may also include the shape of the guard band.

and mapping the synchronous signal sequence to a row corresponding to any delay tap on a resource grid of a delay Doppler domain.

Optionally, in a case that the first communication device does not acquire the channel quality related information, the synchronization signal sequence is mapped to a row corresponding to any delay tap on a resource grid of a delay-doppler domain.

Optionally, when the base station does not have the prior information of the channel, the first mapping method or the second mapping method in fig. 10 is directly adopted.

Alternatively, from the perspective of reducing the complexity of receiver detection, the mapping manner one in fig. 10 may be adopted, that is, the synchronization signal sequence is mapped onto a row corresponding to any delay tap on the resource grid of the delay-doppler domain.

based on a PN sequence, a synchronization signal sequence associated with the physical layer identification is generated.

Alternatively, the synchronization signal sequence may be generated based on a PN sequence;

alternatively, the synchronization signal sequence associated with the physical layer identifier may be generated based on a PN sequence, which is associated with the physical layer identifier.

Optionally, the embodiments of the present application may be applied to a downlink, where the first communication device is a network side device, the second communication device is a terminal, and the physical layer identifier may be a Cell identifier Cell ID.

Optionally, the embodiments of the present application may be applied to a Sidelink, where the first communication device is a terminal, and the second communication device is a terminal, and the physical layer identifier may be a Sidelink ID or a UE ID.

based on the at least two PN sequences, a synchronization signal sequence associated with the physical layer identity is generated.

Alternatively, a synchronization signal sequence associated with the physical layer identity may be generated based on the at least two PN sequences.

For example, the synchronization signal sequence may be generated by two or three PN sequences, and the PN sequences collectively indicate a Cell ID or collectively indicate a Sidelink ID or a UE ID.

Optionally, a partial synchronization signal sequence generated by each of the at least two PN sequences is respectively associated with a part of the physical layer identifiers.

Alternatively, the corresponding part of the synchronization signal sequence generated by each of the at least two PN sequences may be associated with a part of the physical layer identity.

Alternatively, each of the plurality of PN sequences that generate the synchronization signal sequence may be associated with a portion of the physical layer identity.

For example, each of the plurality of PN sequences that generate the synchronization signal sequence may be associated with a portion of the Cell ID.

For example, each PN sequence of the plurality of PN sequences that generate the synchronization signal sequence may be associated with a portion of the Sidelink ID or the UE ID.

Optionally, the generating a synchronization signal sequence associated with a physical layer identity based on at least two PN sequences includes:

the at least two PN sequences are placed in an interleaving mode, wherein the interleaving mode of the at least one PN sequence is associated with a physical layer identifier or a part of the physical layer identifier; or

The at least two PN sequences are placed end to end.

Optionally, when generating the synchronization signal sequence associated with the physical layer identifier based on at least two PN sequences, the synchronization signal sequence may be generated by interleaving multiple PN sequences, where the interleaving manner is associated with the physical layer identifier or part of the physical layer identifier.

Alternatively, when generating the synchronization signal sequence associated with the physical layer identifier based on at least two PN sequences, the synchronization signal sequence may be generated by interleaving or sequentially connecting a plurality of PN sequences according to a fixed rule.

Optionally, when generating the synchronization signal sequence associated with the physical layer identifier based on at least two PN sequences, the at least two PN sequences may be placed end to generate the synchronization signal sequence.

Optionally, the partial synchronization signal generated by each of the at least two PN sequences is associated with a physical layer identity.

Optionally, when the synchronization signal sequence associated with the physical layer identifier is generated based on at least two PN sequences, each of the at least two PN sequences is associated with all physical layer identifiers.

Alternatively, the LFSRs used to generate the synchronization signal sequence may be the same or different.

the at least two PN sequences are arranged in an interleaving mode, wherein the interleaving mode of the at least one PN sequence is associated with a physical layer identifier or a part of the physical layer identifier; or

Starting from a preset row of resource grids, the at least two PN sequences are sequentially mapped on at least two rows of resource grids behind the row of resource grids, and each resource grid in the at least two rows of resource grids maps one PN sequence in the at least two PN sequences, wherein the position of the preset row of resource grids is associated with the communication opposite terminal.

Optionally, when generating the synchronization signal sequence associated with the physical layer identifier based on at least two PN sequences, each of the at least two PN sequences is associated with all physical layer identifiers, wherein a plurality of PN sequences may be interleaved and their interleaving is associated with the physical layer identifier.

Optionally, when generating the synchronization signal sequence associated with the physical layer identifier based on at least two PN sequences, each of the at least two PN sequences is associated with all physical layer identifiers, where at least two PN sequences may be sequentially mapped on at least two rows of resource grids following the row of resource grids starting from a preset row of resource grids, and at least two rows of resource grids sequentially map the at least two PN sequences, where the preset row of resource grids may be associated with the corresponding end of communication, for example, may be started from delay tap k, and two or three PN sequences are respectively mapped on delay tap (k, k +1) or (k, k +1, k + 2). Where k is associated with the physical layer identity.

Optionally, the synchronization signal is divided into a first part and a second part;

the first part is used for synchronous timing as a synchronous signal;

the second portion is for indicating a physical layer identification.

Alternatively, only a part of the synchronization signal sequences generated by one or more PN sequences can be used as timing blind detection; another part is used for detection of information bits after finding the synchronization timing, e.g. for indicating the physical layer identity.

According to the embodiment of the application, the synchronous signal sequence is used as the synchronous signal to be transmitted in the delay Doppler domain, so that the good autocorrelation and cross-correlation performance of the synchronous signal is kept, the synchronous detection step of the receiving side is simplified, the method is suitable for the implementation of simplified OTFS engineering, and the extra complexity caused by the fact that the synchronous signal is inserted in the time-frequency domain is avoided.

Fig. 12 is a second flowchart of a synchronization signal transmission method according to an embodiment of the present application, and as shown in fig. 12, the method includes the following steps:

step 1200, the second communication device receives a time domain sampling point of a synchronization signal sequence;

and 1210, performing synchronous timing detection on the time domain sampling points of the synchronization signal sequence.

Optionally, the embodiment of the present application may be applied to a downlink, where the first communication device may be a network side device, such as a base station, and the second communication device may be a terminal UE.

Optionally, the embodiment of the present application may be applied to a sidelink, where the first communication device may be a terminal UE, and the second communication device may be a terminal UE.

Optionally, the first communication device may employ a sequence-based synchronization signal sequence for OTFS modulation, and send the synchronization signal sequence to the second communication device in the delay doppler domain, and after the second communication device receives the synchronization signal sequence in the delay doppler domain, the second communication device may perform synchronous timing detection on a time domain sampling point of the synchronization signal sequence.

Alternatively, the synchronization signal sequence is generated based on a sequence with good auto-correlation and cross-correlation performance, and after modulating the synchronization signal sequence, the first communication device may map the synchronization signal sequence onto a delay doppler domain resource grid for transmission.

Optionally, the synchronization signal sequence is transmitted over a pilot frame.

Optionally, after the synchronization signal sequence is processed by the OTFS system baseband and changed into the transmitted time-domain sampling point, good auto-correlation and cross-correlation performance can still be maintained. Therefore, the second communication device, i.e. the receiving end, can directly detect the synchronization signal based on the received time domain sampling point, and acquire the synchronization timing without additional processing steps.

Optionally, in the embodiments of the present application, an exclusive synchronization mechanism is designed for OTFS modulation, so as to better utilize the advantages of an OTFS system.

Optionally, the performing synchronous timing detection on the time domain sampling points of the synchronization signal sequence includes:

under the condition that the second communication equipment has pilot frequency mapping relevant information, sampling the synchronous signal sequence based on the pilot frequency mapping relevant information to obtain the time domain sampling point;

and carrying out synchronous timing detection on the time domain sampling points.

Optionally, when the second communication device, such as the UE, has the pilot mapping related information, the second communication device may extract the time domain sampling point with the total length QN of the specific location for detection.

Alternatively, the synchronization signal sequence may be sampled based on pilot mapping related information to obtain sampling points.

Optionally, the pilot mapping related information may be pilot mapping prior information;

optionally, the second communication device may have pilot mapping related information in case:

1) the system may support only one type of pilot mapping information or there may be a known default mapping of pilots for synchronization.

2) The system may support several pilot mapping schemes and the second communication device may perform a traversal search.

3) The second communication device may have a priori information of the first communication device pilot mapping configuration. For example, a second communication device may have previously connected to a first communication device and later be in an idle state, and now need to be synchronously re-established, while retaining the last configuration information.

and under the condition that the second communication equipment does not have pilot frequency mapping related information, performing synchronous timing detection on all time domain sampling points of the synchronous signal sequence.

Optionally, the second communication device, such as the UE, may detect a time domain sampling point with a length of MN when having pilot mapping related information.

Alternatively, all time domain sampling points of the synchronization signal sequence may be subjected to synchronization timing detection based on the pilot mapping correlation information.

Alternatively, the second communication device may not have pilot mapping related information in the following cases: the second communication equipment is started up and is accessed into the first communication equipment for the first time without any prior information.

Optionally, the method further comprises:

determining channel quality related information based on the synchronization signal sequence if the synchronization signal sequence is used for synchronization timing and for acquiring channel quality related information.

Alternatively, in the case where a synchronization signal sequence is used for synchronization timing and for acquiring channel quality related information, the channel quality related information may be determined based on the synchronization signal sequence.

Alternatively, in the case that the synchronization signal sequence is used for synchronizing timing and for acquiring channel quality related information, and the pilot frame in which the synchronization signal sequence is located further includes data, the channel quality related information may be determined based on the synchronization signal sequence.

Optionally, the method further comprises:

and when the pilot frame in which the synchronization signal sequence is positioned comprises a data signal, demodulating the data signal based on the channel quality related information.

Alternatively, in the case where the synchronization signal sequence is used for synchronizing timing and for acquiring channel quality related information, and the pilot frame in which the synchronization signal sequence is located further includes data, the channel quality related information may be determined based on the synchronization signal sequence.

Alternatively, the pilot frame may carry multiple functions: acquiring timing synchronization; obtaining accurate CSI; and serving user data demodulation (using QCL relationships) in subsequent time slots; pilot resources for subsequent time slots are adapted; and after synchronous timing, recovering a delay Doppler domain resource grid, and utilizing the pilot frequency to carry out channel estimation so as to demodulate data in the frame.

It should be noted that, in the synchronization signal transmission method provided in the embodiment of the present application, the execution main body may be a synchronization signal transmission apparatus, or a control module in the synchronization signal transmission apparatus for executing the synchronization signal transmission method. In the embodiment of the present application, a method for executing a synchronization signal transmission by a synchronization signal transmission apparatus is taken as an example to describe the synchronization signal transmission apparatus provided in the embodiment of the present application.

Fig. 13 is a schematic structural diagram of a synchronization signal transmission apparatus according to an embodiment of the present application, and as shown in fig. 13, the apparatus includes: a first generation module 1310, and a first transmission module 1320; wherein:

the first generating module 1310 is configured to generate a synchronization signal sequence mapped in a delayed doppler domain by the first communication device;

the first transmission module 1320 is used for the first communication device to transmit the time domain sampling point of the synchronization signal sequence.

Alternatively, the synchronization signal transmission apparatus may generate the synchronization signal sequence mapped in the delayed doppler domain by the first generation module 1310; the time domain sampling points of the synchronization signal sequence may then be transmitted by the first transmission module 1320.

Optionally, the first generating module is configured to:

determining a resource grid pattern of the synchronization signal sequence mapped to a delay-Doppler domain based on the channel quality related information.

Optionally, the first generating module is configured to:

a synchronization signal sequence associated with a physical layer identity is generated based on the at least two PN sequences.

Optionally, the first generating module is configured to:

the at least two PN sequences are placed in an interleaving mode, wherein the interleaving mode of the at least one PN sequence is associated with the physical layer identification or part of the physical layer identification of the communication opposite end; or

The at least two PN sequences are placed end to end.

Optionally, the partial synchronization signal generated by each of the at least two PN sequences is associated with the physical layer identity.

Optionally, the first generating module is configured to:

the at least two PN sequences are arranged in an interleaving mode, wherein the interleaving mode of the at least one PN sequence is associated with the physical layer identifier or part of the physical layer identifier; or

the first part is used for synchronous timing as a synchronous signal;

the second portion is for indicating a physical layer identification.

The synchronization signal transmission apparatus in the embodiment of the present application may be an apparatus or an electronic device having an operating system, or may be a component, an integrated circuit, or a chip in a terminal. The device can be a mobile terminal or a non-mobile terminal. By way of example, the mobile terminal may include, but is not limited to, the above-listed type of terminal 11, and the non-mobile terminal may be a server, a Network Attached Storage (NAS), a Personal Computer (PC), a Television (TV), a teller machine, a kiosk, or the like, and the embodiments of the present application are not limited in particular.

The synchronization signal transmission apparatus provided in the embodiment of the present application can implement each process implemented by the method embodiments of fig. 9 to fig. 11, and achieve the same technical effect, and is not described herein again to avoid repetition.

Fig. 14 is a second schematic structural diagram of a synchronization signal transmission apparatus according to an embodiment of the present application, and as shown in fig. 14, the apparatus includes: a first receiving module 1410 and a first detecting module 1420, wherein:

the first receiving module 1410 is configured to receive, by the second communications device, time-domain sampling points of a synchronization signal sequence;

the first detection module 1420 is configured to perform synchronous timing detection on the time domain sampling points of the synchronization signal sequence by the second communication device.

Alternatively, the synchronization signal transmission apparatus may receive the time domain sampling point of the synchronization signal sequence through the first receiving module 1410; the time domain samples of the synchronization signal sequence may then be detected for synchronization timing by the first detection module 1420.

Optionally, the first detection module is configured to:

under the condition that the second communication equipment has pilot frequency mapping related information, sampling the synchronous signal sequence based on the pilot frequency mapping related information to obtain the time domain sampling point;

Optionally, the first detecting module is configured to:

Optionally, the apparatus further comprises:

the first determination is not for determining the channel quality related information based on the synchronization signal sequence in a case where the synchronization signal sequence is used for synchronization timing and for acquiring the channel quality related information.

Optionally, the apparatus further comprises:

a first demodulation module, configured to demodulate a data signal based on the channel quality related information when a pilot frame in which the synchronization signal sequence is located includes the data signal.

The synchronization signal transmission device in the embodiment of the present application may be a device, and may also be a component, an integrated circuit, or a chip in a terminal. The device can be a mobile terminal or a non-mobile terminal. By way of example, the mobile terminal may include, but is not limited to, the above-listed type of terminal 11, and the non-mobile terminal may be a server, a Network Attached Storage (NAS), a Personal Computer (PC), a Television (TV), a teller machine, a kiosk, or the like, and the embodiments of the present application are not limited in particular.

The synchronization signal transmission device in the embodiment of the present application may be a device having an operating system. The operating system may be an Android (Android) operating system, an ios operating system, or other possible operating systems, and embodiments of the present application are not limited specifically.

The synchronization signal transmission apparatus provided in the embodiment of the present application can implement each process implemented in the method embodiment of fig. 12, and achieve the same technical effect, and is not described here again to avoid repetition.

Optionally, fig. 15 is a schematic structural diagram of a communication device according to an embodiment of the present application, and as shown in fig. 15, the communication device 1500 includes a processor 1501, a memory 1502, and a program or an instruction stored in the memory 1502 and executable on the processor 1501, for example, when the communication device 1500 is a terminal, the program or the instruction is executed by the processor 1501 to implement the processes of the foregoing method embodiments, and the same technical effect can be achieved. When the communication device 1500 is a network-side device, the program or the instructions are executed by the processor 1501 to implement the processes of the method embodiments described above, and the same technical effects can be achieved.

Optionally, the second communication device may be a terminal, and the first communication device may be a network side device;

alternatively, the first communication device may be a terminal and the second communication device may be a terminal.

Fig. 16 is a schematic hardware structure diagram of a terminal according to an embodiment of the present application.

The terminal 1600 includes, but is not limited to: at least some of the components of the radio frequency unit 1601, the network module 1602, the audio output unit 1603, the input unit 1604, the sensor 1605, the display unit 1606, the user input unit 1607, the interface unit 1608, the memory 1609, and the processor 1610.

Those skilled in the art will appreciate that terminal 1600 may also include a power supply (e.g., a battery) for powering the various components, which may be logically coupled to processor 1610 via a power management system to perform the functions of managing charging, discharging, and power consumption via the power management system. The terminal structure shown in fig. 16 does not constitute a limitation of the terminal, and the terminal may include more or less components than those shown, or combine some components, or have a different arrangement of components, and will not be described again.

It should be understood that in the embodiment of the present application, the input Unit 1604 may include a Graphics Processing Unit (GPU) 16041 and a microphone 16042, and the Graphics processor 16041 processes image data of still pictures or videos obtained by an image capturing device (such as a camera) in a video capturing mode or an image capturing mode. The display unit 1606 may include a display panel 16061, and the display panel 16061 may be configured in the form of a liquid crystal display, an organic light emitting diode, or the like. The user input unit 1607 includes a touch panel 16071 and other input devices 16072. The touch panel 16071 is also called a touch screen. The touch panel 16071 may include two parts of a touch detection device and a touch controller. Other input devices 16072 may include, but are not limited to, a physical keyboard, function keys (e.g., volume control keys, switch keys, etc.), a trackball, a mouse, and a joystick, which are not described in detail herein.

In the embodiment of the present application, the radio frequency unit 1601 receives information from a communication peer and then processes the information to the processor 1610; and in addition, the information to be transmitted is sent to the opposite communication terminal. In general, the radio frequency unit 1601 includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like.

The memory 1609 may be used to store software programs or instructions as well as various data. The memory 1609 may mainly include a stored program or instruction area and a stored data area, wherein the stored program or instruction area may store an operating system, an application program or instruction (such as a sound playing function, an image playing function, etc.) required for at least one function, and the like. In addition, the Memory 1609 may include a high-speed random access Memory, and may also include a nonvolatile Memory, which may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable Programmable PROM (EPROM), an Electrically Erasable Programmable ROM (EEPROM), or a flash Memory. Such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device.

Processor 1610 may include one or more processing units; alternatively, processor 1610 may integrate an application processor, which handles primarily the operating system, user interface, and applications or instructions, and a modem processor, which handles primarily wireless communications, such as a baseband processor. It is to be appreciated that the modem processor described above may not be integrated into processor 1610.

Wherein, the processor 1610 is configured to:

generating a synchronous signal sequence mapped in a delay Doppler domain;

and transmitting the time domain sampling point of the synchronous signal sequence.

Optionally, processor 1610 is configured to:

the transmitting the synchronization signal sequence in the delay-doppler domain includes:

Optionally, processor 1610 is configured to:

And determining a resource grid mode of the synchronization signal sequence mapped to a delay-Doppler domain based on the average value of the obtained at least two pieces of channel quality related information.

Optionally, processor 1610 is configured to:

the at least two PN sequences are arranged in an interleaving mode, wherein the interleaving mode of the at least one PN sequence is associated with the physical layer identification or part of the physical layer identification of the communication opposite end; or

The at least two PN sequences are placed end to end.

Optionally, the partial synchronization signal generated by each of the at least two PN sequences is associated with the physical layer identifier.

Optionally, processor 1610 is configured to:

the at least two PN sequences are arranged in an interleaving mode, wherein the interleaving mode of the at least one PN sequence is associated with the physical layer identification or part of the physical layer identification; or

the first part is used for synchronous timing as a synchronous signal;

the second portion is for indicating a physical layer identification.

Alternatively, the first and second electrodes may be,

optionally, processor 1610 is configured to:

receiving a time domain sampling point of a synchronous signal sequence;

and carrying out synchronous timing detection on the time domain sampling points of the synchronous signal sequence.

Optionally, processor 1610 is configured to:

and when the pilot frame in which the synchronization signal sequence is positioned comprises a data signal, demodulating the data signal based on the channel quality related information. According to the embodiment of the application, the synchronous signal sequence is used as the synchronous signal to be transmitted in the delay Doppler domain, so that the good autocorrelation and cross-correlation performance of the synchronous signal is kept, the synchronous detection step of the receiving side is simplified, the method is suitable for the implementation of simplified OTFS engineering, and the extra complexity caused by the fact that the synchronous signal is inserted in the time-frequency domain is avoided.

The terminal embodiment in the embodiment of the present application is a product embodiment corresponding to the method embodiment, and all implementation manners in the method embodiment are applicable to the terminal embodiment, and may also achieve the same or similar technical effects, so that details are not repeated herein.

As shown in fig. 17, the network-side device 1700 includes: antenna 1701, radio frequency device 1702, baseband device 1703. An antenna 1701 is coupled to the radio frequency device 1702. In the uplink direction, rf device 1702 receives information via antenna 1701 and sends the received information to baseband device 1703 for processing. In the downlink direction, the baseband device 1703 processes information to be transmitted and transmits the processed information to the rf device 1702, and the rf device 1702 processes the received information and transmits the processed information via the antenna 1701.

The above band processing apparatus may be located in the baseband apparatus 1703, and the method performed by the network side device in the above embodiment may be implemented in the baseband apparatus 1703, where the baseband apparatus 1703 includes a processor 1704 and a memory 1705.

The baseband device 1703 may include, for example, at least one baseband board on which a plurality of chips are disposed, as shown in fig. 17, where one of the chips, for example, the processor 1704, is connected to the memory 1705 to call up a program in the memory 1705 to perform the network device operations shown in the above method embodiments.

The baseband device 1703 may further include a network interface 1706, such as a Common Public Radio Interface (CPRI), for exchanging information with the radio frequency device 1702.

Specifically, the network side device in the embodiment of the present application further includes: the instructions or programs stored in the memory 1705 and executable on the processor 1704 call the instructions or programs in the memory 1705 to execute the method executed by each module shown in fig. 13, and achieve the same technical effect, and are not described herein in detail to avoid repetition.

Wherein the processor 1704 is configured to:

generating a synchronous signal sequence mapped in a delay Doppler domain;

Optionally, the processor 1704 is configured to:

and mapping the synchronous signal sequence to a line corresponding to any delay tap on a resource grid of a delay Doppler domain.

Optionally, the processor 1704 is configured to:

The at least two PN sequences are placed end to end.

Optionally, the processor 1704 is configured to:

the first part is used for synchronous timing as a synchronous signal;

the second portion is for indicating a physical layer identification.

The network side device embodiment in the embodiment of the present application is a product embodiment corresponding to the above method embodiment, and all implementation manners in the above method embodiment are applicable to the terminal embodiment, and may also achieve the same or similar technical effects, so that details are not described herein again.

The embodiment of the present application further provides a readable storage medium, where a program or an instruction is stored on the readable storage medium, and when the program or the instruction is executed by a processor, the program or the instruction implements each process of the above-mentioned synchronization signal transmission method embodiment, and can achieve the same technical effect, and in order to avoid repetition, details are not repeated here.

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 Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and so on.

The embodiment of the present application further provides a chip, where the chip includes a processor and a communication interface, the communication interface is coupled to the processor, and the processor is configured to run a network-side device program or an instruction, so as to implement each process of the above embodiment of the synchronization signal transmission method, and achieve the same technical effect, and in order to avoid repetition, the description is omitted here.

It should be understood that the chips mentioned in the embodiments of the present application may also be referred to as a system-on-chip, a system-on-chip or a system-on-chip, etc.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other elements in a process, method, article, or apparatus that comprises the element. Further, it should be noted that the scope of the methods and apparatuses in the embodiments of the present application is not limited to performing the functions in the order illustrated or discussed, but may include performing the functions in a substantially simultaneous manner or in a reverse order based on the functions recited, e.g., the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solutions of the present application may be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal (such as a mobile phone, a computer, a server, or a network device) to execute the method according to the embodiments of the present application.

While the present embodiments have been described with reference to the accompanying drawings, it is to be understood that the present embodiments are not limited to those precise embodiments, which are intended to be illustrative rather than restrictive, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope of the appended claims.

Claims

1. A method for transmitting a synchronization signal, comprising:

and the first communication equipment transmits the time domain sampling point of the synchronous signal sequence.

2. The method of claim 1, wherein the generating the synchronization signal sequence mapped to the delay-doppler domain comprises:

3. The method of claim 2, wherein the generating the synchronization signal sequence mapped to the delay-doppler domain comprises:

4. The method of claim 2, wherein the generating the synchronization signal sequence mapped to the delay-doppler domain comprises:

5. The method of claim 2, wherein the generating the synchronization signal sequence mapped to the delay-doppler domain comprises:

6. The method for transmitting the synchronization signal according to any one of claims 1 to 5, wherein the generating the synchronization signal sequence mapped to the delay-Doppler domain comprises:

7. The method according to claim 6, wherein the determining the resource grid pattern of the synchronization signal sequence mapped to the delay-Doppler domain based on the channel quality related information comprises:

8. The method for transmitting the synchronization signal according to any one of claims 1 to 5, wherein the generating the synchronization signal sequence mapped to the delay-Doppler domain comprises:

and mapping the synchronous signal sequence to a row corresponding to the delay dimension coordinate delay tap of any delay Doppler resource grid on the resource grids of the delay Doppler domain.

9. The method for transmitting the synchronization signal according to any one of claims 1 to 5, wherein the generating the synchronization signal sequence mapped to the delay-Doppler domain comprises:

10. The method for transmitting the synchronization signal according to any one of claims 1 to 5, wherein the generating the synchronization signal sequence mapped to the delay-Doppler domain comprises:

11. The method of claim 10, wherein a partial synchronization signal sequence generated by each of the at least two PN sequences is associated with a part of the physical layer id.

12. The method of claim 11, wherein the generating the synchronization signal sequence associated with the physical layer identity based on the at least two PN sequences comprises:

The at least two PN sequences are placed end to end.

13. The method of claim 10, wherein the partial synchronization signal generated by each of the at least two PN sequences is associated with the physical layer id.

14. The method of claim 13, wherein the generating the synchronization signal sequence associated with the physical layer identity based on the at least two PN sequences comprises:

15. The synchronization signal transmission method according to any one of claims 10 to 13, wherein the synchronization signal is divided into a first part and a second part;

the first part is used for synchronous timing as a synchronous signal;

the second portion is for indicating a physical layer identification.

16. A method for transmitting a synchronization signal, comprising:

the second communication equipment receives time domain sampling points of the synchronous signal sequence;

17. The method according to claim 16, wherein the performing synchronization timing detection on the time domain sampling points of the synchronization signal sequence comprises:

18. The method according to claim 16, wherein the performing synchronization timing detection on the time domain sampling points of the synchronization signal sequence comprises:

19. The synchronization signal transmission method according to any one of claims 16 to 18, wherein the method further comprises:

in case the synchronization signal sequence is used for synchronizing timing and for acquiring channel quality related information, channel quality related information is determined based on the synchronization signal sequence.

20. The method of claim 19, further comprising:

21. A synchronization signal transmission apparatus, comprising:

22. The synchronization signal transmission apparatus of claim 21, wherein the first generating module is configured to:

23. The apparatus for transmitting synchronization signals according to claim 22, wherein said first generating module is configured to:

24. The apparatus for transmitting synchronization signals according to claim 22, wherein said first generating module is configured to:

in the case that the synchronization signal sequence is used for synchronization timing and for acquiring channel quality related information, a guard band is reserved for the synchronization signal sequence on a resource grid of the delay-doppler domain.

25. The apparatus for transmitting synchronization signals according to claim 22, wherein said first generating module is configured to:

26. The synchronization signal transmission apparatus according to any one of claims 21 to 25, wherein the first generation module is configured to:

27. The synchronization signal transmission apparatus of claim 26, wherein the first generation module is configured to:

28. The synchronization signal transmission apparatus according to any one of claims 21 to 25, wherein the first generation module is configured to:

29. The synchronization signal transmission apparatus according to any one of claims 21 to 25, wherein the first generation module is configured to:

30. The synchronization signal transmission apparatus according to any one of claims 21 to 25, wherein the first generation module is configured to:

31. The apparatus of claim 30, wherein a partial synchronization signal sequence generated by each of the at least two PN sequences is respectively associated with a portion of the physical layer identifiers.

32. The synchronization signal transmission apparatus of claim 31, wherein the first generating module is configured to:

The at least two PN sequences are placed end to end.

33. The apparatus of claim 30, wherein the partial synchronization signal generated by each of the at least two PN sequences is associated with the physical layer identity.

34. The synchronization signal transmission apparatus of claim 33, wherein the first generation module is configured to:

35. The synchronization signal transmission apparatus of any one of claims 30 to 33, wherein the synchronization signal is divided into a first part and a second part;

the first part is used for synchronous timing as a synchronous signal;

the second portion is for indicating a physical layer identity.

36. A synchronization signal transmission apparatus, comprising:

37. The apparatus for transmitting synchronization signals according to claim 36, wherein said first detecting module is configured to:

38. The apparatus for transmitting synchronization signal according to claim 36, wherein the first detecting module is configured to:

39. The synchronization signal transmission apparatus of any one of claims 36 to 38, further comprising:

a first determining module, configured to determine channel quality related information based on the synchronization signal sequence if the synchronization signal sequence is used for synchronization timing and for acquiring channel quality related information.

40. The synchronization signal transmission apparatus of claim 39, wherein the apparatus further comprises:

41. A communication device comprising a processor, a memory and a program or instructions stored on the memory and executable on the processor, the program or instructions when executed by the processor implementing the steps of the synchronization signal transmission method according to any one of claims 1 to 15.

42. A communication device comprising a processor, a memory and a program or instructions stored on the memory and executable on the processor, the program or instructions when executed by the processor implementing the steps of the synchronization signal transmission method according to any one of claims 16 to 20.

43. A readable storage medium, characterized in that a program or instructions are stored thereon, which program or instructions, when executed by the processor, carry out the steps of the synchronization signal transmission method according to any one of claims 1 to 15, or carry out the steps of the synchronization signal transmission method according to any one of claims 16 to 20.