CN111294306B

CN111294306B - Transmission method and device of reference signal

Info

Publication number: CN111294306B
Application number: CN201811496784.6A
Authority: CN
Inventors: 刘凤威; 陈磊
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-12-07
Filing date: 2018-12-07
Publication date: 2021-08-13
Anticipated expiration: 2038-12-07
Also published as: WO2020114317A1; CN111294306A

Abstract

Transmission method of reference signalAnd means for reducing a PAPR of the reference signal. The method comprises the following steps: the first device determines a second sequence d n]Wherein d [ n ] is]＝c[<n+n₀>_K]，n＝0、1、……、N‑1，n₀In order to be the value of the initial shift,<n+n₀>_Kdenotes n + n₀Modulo K, n₀Is a non-negative integer, c [ m ]]The sequence is a first sequence, m is 0,1, … … and K-1, K is more than or equal to N, and N, K is a positive integer; the first equipment processes the second sequence to obtain a reference signal; and the first equipment multiplexes the reference signal and a data channel and sends the multiplexed signal to the second equipment.

Description

Transmission method and device of reference signal

Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a transmission method and device of a reference signal.

Background

In a New Radio (NR) system, an Orthogonal Frequency Division Multiplexing (OFDM) waveform and a discrete fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) waveform are used in an uplink. The DFT-s-OFDM waveform has good compatibility with the OFDM waveform, and a peak-to-average power ratio (PAPR) when the DFT-s-OFDM waveform is adopted is significantly lower than a PAPR when the OFDM waveform is adopted. When the DFT-s-OFDM waveform works in the same power amplifier, the DFT-s-OFDM waveform can achieve larger output power than the OFDM waveform, and therefore the DFT-s-OFDM waveform can improve uplink coverage.

To further improve the uplink coverage, the uplink data channel is modulated with pi/2-Binary Phase Shift Keying (BPSK) and with DFT-s-OFDM waveforms. The pi/2-BPSK modulation can perform Frequency Domain Spectral Shaping (FDSS), thereby enabling a lower PAPR to be obtained. However, PAPRs of uplink reference signals generated by adopting QPSK sequences and ZC sequences and DFT-s-OFDM waveforms and adopting QPSK sequences and ZC sequences are close to those of DFT-s-OFDM waveforms modulated by QPSK, namely larger than PAPR of DFT-s-OFDM waveforms modulated by pi/2-BPSK. After the spectrum shaping is adopted, the difference of the PAPRs of the two can be further increased. In summary, when the DFT-s-OFDM waveform is adopted in the uplink, the PAPR of the uplink reference signal is larger than that of the data channel.

If the PAPR of the uplink reference signal is greater than the PAPR of the data channel, the following problems may be caused. The PAPR of the combined signal of the reference signal and the data channel is increased, so that the total output power of the signal is reduced; the power of the reference signal is backed off, so that the channel estimation precision is reduced; if the reference signal is not power backed off, the PAPR of the reference signal is higher than the PAPR of the data channel, which may cause the reference signal to have large distortion after passing through a Power Amplifier (PA), thereby affecting the channel estimation performance.

Disclosure of Invention

The embodiment of the application provides a transmission method and a transmission device of a reference signal, which are used for solving the problem that the PAPR of an uplink reference signal is larger than that of a data channel when DFT-s-OFDM waveforms are adopted in the uplink.

The embodiment of the application provides the following specific technical scheme:

in a first aspect, a method for transmitting a reference signal is provided, where an execution subject of the method is represented by a first device, and the first device may be a terminal or a network device. When the first equipment is a terminal, the second equipment is network equipment; and when the first equipment is network equipment, the second equipment is a terminal. The method is mainly realized by the following steps: the first device firstly obtains a reference signal sequence on a time domain, obtains the reference signal sequence on a frequency domain after time-frequency domain conversion, generates a reference signal and sends the reference signal. The reference signal sequence in the time domain is easier to achieve the low PAPR requirement.

In one possible design, the first device determines the second sequence d [ n ]]Wherein d [ n ]]Has a length of N, d [ N ]]＝c[<n+n₀>_K]，n＝0、1、……、N-1，n₀In order to be the value of the initial shift,<n+n₀>_Kdenotes n + n₀Modulus of K, c [ m ]]Is a first sequence, m is 0,1, … …, K-1, the c [ m]The length of (A) is K, K is more than or equal to N, N, K is a positive integer, N₀Is a non-negative integer; the first equipment processes the second sequence to obtain a reference signal; and the first equipment multiplexes the reference signal and a data channel and sends the multiplexed signal to the second equipment. The second sequence is a reference signal sequence in a time domain, and is selected from the first sequence in order to match the length of the reference signal sequence. By the above method fromAnd intercepting the second sequence from the first sequence, finally generating and sending the reference signal, so that the time domain reference signal has better frequency domain flatness after being converted into the frequency domain reference signal, thereby ensuring better channel estimation performance.

In one possible design, the first device determines the first sequence c [ m ]]And said n₀The information of (a); the first device according to said first sequence c [ m ]]And said n₀Determines the second sequence d [ n ]]。

In one possible design, the method further includes: the first device determines a sequence number, which may also be referred to as a number. The first device determines the first sequence c [ m ] indexed by the sequence number]And said n₀. In particular, each possible second sequence consists of a first sequence c [ m ]]And initial shift value n₀The information of (3) determines that the L possible second sequences are indexed by sequence numbers. The L possible second sequences are predetermined, specified by the protocol or configured for the terminal by the network device. In an optional manner, if the first device is a network device and the second device is a terminal, the first device sends the information of the sequence number to the second device; and if the first equipment is a terminal and the second equipment is network equipment, the first equipment receives the information of the sequence number from the second equipment. Therefore, the sequence with better frequency domain flatness performance can be obtained on the basis of the existing sequence.

In one possible design, the first device is a network device, the second device is a terminal, and the first device sends the first sequence c [ m ] to the second device]And said n₀The information of (a); or, the first device sends the first sequence c [ m ] to the second device]The information of (1). In an alternative, the first device selects the first sequence c [ M ] from M candidate sequences]Selecting said n from O candidate initial shift values₀The M, O is a positive integer; the first device transmits the first sequence c [ m ]]And said n₀To the second device. Thus, the method can acquire the sequence with the existing sequenceSequences with better frequency domain flatness performance.

In one possible design, the first device is a terminal, the second device is a network device, and the first device receives the first sequence c [ m ] from the second device]The information of (a); alternatively, the first device receives the first sequence c [ m ] from the second device]And said n₀The information of (1). Therefore, the sequence with better frequency domain flatness performance can be obtained on the basis of the existing sequence.

In one possible design, the first sequence c [ m ] is a Gold sequence, and the information of the first sequence c [ m ] is an initialization parameter of c [ m ].

In one possible design, the first sequence is a binary sequence or a ternary sequence.

In one possible design, the first sequence is a binary sequence and the first device performs pi/2-binary phase shift keying BPSK modulation on the second sequence.

In one possible design, the first sequence is a ternary sequence, and the first device performs memory phase modulation on the second sequence.

In one possible design, the multiplexed signal includes one or more orthogonal frequency division multiplexing, OFDM, symbols in which the first device carries data modulation symbols and the reference signal.

In one possible design, the reference signal occupies 1/2 the length of one OFDM symbol in the one OFDM symbol^mAnd m is a non-negative integer.

In one possible design, when the terminal has the capability of supporting the reference signal sequence referred to in the present application, the terminal reports the capability to the network device, and the network device determines whether the terminal supports the capability according to the reporting of the terminal.

In one possible design, the reference signal includes a demodulation reference signal (DMRS) or a channel state information-reference signal (CSI-RS).

In one possible design, the N is related to a data channel bandwidth in one possible design.

In a second aspect, there is provided an apparatus for transmitting a reference signal, the apparatus being applied to a terminal, or the apparatus being applied to a network device, or the apparatus being a terminal, or the apparatus being a network device, the apparatus having functions of implementing the method performed by the first device in any one of the possible designs of the first aspect and the first aspect, and including means (means) corresponding to the steps or functions described for performing the aspects. The steps or functions may be implemented by software, or by hardware (e.g., a circuit), or by a combination of hardware and software.

In one possible design, the apparatus includes one or more processors and a communication unit. The one or more processors are configured to enable the transmitting device of the reference signal to perform the functions in the above-described method. For example, a second sequence d [ n ] is determined from the first sequence c [ m ], the second sequence is processed to obtain a reference signal, and the reference signal is multiplexed with a data channel. The communication unit is used for supporting the transmission device of the reference signal to communicate with other equipment, and realizing receiving and/or sending functions. For example, the multiplexed signal is transmitted.

Optionally, the apparatus may also include one or more memories for coupling with the processor that hold the necessary program instructions and/or data for the apparatus. The one or more memories may be integral with the processor or separate from the processor. The present application is not limited.

The communication unit may be a transceiver, or a transceiving circuit. Optionally, the transceiver may also be an input/output circuit or interface.

The device may also be a communication chip. The communication unit may be an input/output circuit or an interface of the communication chip.

In another possible design, the apparatus for transmitting the reference signal includes a transceiver, a processor, and a memory. The processor is configured to control the transceiver or the input/output circuit to transceive signals, the memory is configured to store a computer program, and the processor is configured to execute the computer program in the memory, so that the apparatus performs the method of the first aspect or any one of the possible designs of the first aspect.

In a third aspect, a system is provided, where the system includes a terminal and a network device, where the terminal performs the method in the first network device in the first aspect or any one of the possible designs of the first aspect; alternatively, the network device performs the method in the first network device in the first aspect or any one of the possible designs of the first aspect.

In a fourth aspect, there is provided a computer-readable storage medium storing a computer program comprising instructions for performing the first aspect or any one of the possible design methods of the first aspect.

In a fifth aspect, there is provided a computer program product comprising: computer program code for causing a computer to perform the method of the first aspect or any one of the possible designs of the first aspect, when said computer program code is run on a computer.

Drawings

FIG. 1 is a system architecture diagram according to an embodiment of the present application;

fig. 2 is a schematic flow chart illustrating a method for transmitting a reference signal according to an embodiment of the present disclosure;

FIG. 3 is a diagram illustrating a sub-sequence truncation in an embodiment of the present application;

fig. 4 is a schematic diagram of a comb-shaped DMRS pattern in an embodiment of the present application;

FIG. 5 is a diagram illustrating ternary-sequence memory-phase modulation according to an embodiment of the present application;

fig. 6a is one of schematic diagrams of multiplexing of a time-domain DMRS sequence and data in an embodiment of the present application;

fig. 6b is a second schematic diagram illustrating multiplexing of time-domain DMRS sequences and data in the embodiment of the present application;

FIG. 7 is a diagram illustrating multiplexing of a data channel and a reference signal within a single symbol according to an embodiment of the present application;

FIG. 8 is a schematic diagram of a design of a pre-DFT multiplexing receiver before DFT in an embodiment of the present application;

fig. 9 is a schematic structural diagram of a transmission apparatus for reference signals according to an embodiment of the present application;

fig. 10 is a second schematic structural diagram of a transmission apparatus for reference signals in an embodiment of the present application.

Detailed Description

The embodiment of the application provides a method and a device for transmitting a reference signal, and the method and the device are based on the same inventive concept, and because the principles of solving the problems of the method and the device are similar, the implementation of the device and the method can be mutually referred, and repeated parts are not repeated. In the description of the embodiment of the present application, "and/or" describes an association relationship of associated objects, which means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. At least one referred to in this application means one or more; plural means two or more. In addition, it is to be understood that the terms first, second, etc. in the description of the present application are used for distinguishing between the descriptions and not necessarily for describing a sequential or chronological order.

The transmission method of the reference signal provided by the embodiment of the application can be applied to a fourth generation (4th generation, 4G) communication system, a fifth generation (5th generation, 5G) communication system or various future communication systems. Optionally, the embodiment of the present application is applicable to a communication system using single carrier waveform communication.

The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Fig. 1 shows an architecture of a possible communication system to which the reference signal transmission method provided in the embodiment of the present application is applied, and referring to fig. 1, a communication system 100 includes: a network device 101 and one or more terminals 102. When the communication system 100 includes a core network, the network device 101 may also be connected to the core network. Network device 101 may communicate with IP network 103 through a core network, for example, IP network 103 may be: the internet (internet), a private IP network, or other data network, etc. The network device 101 provides services to terminals 102 within a coverage area. For example, referring to fig. 1, a network device 101 provides wireless access to one or more terminals 102 within the coverage area of the network device 101. A plurality of network devices may be included in communication system 100, such as network device 101'. There may be areas of overlapping coverage between network devices, such as areas of overlapping coverage between network device 101 and network device 101'. The network devices may also communicate with each other, for example, network device 101 may communicate with network device 101'.

The network device 101 is a node in a Radio Access Network (RAN), which may also be referred to as a base station and may also be referred to as a RAN node (or device). Currently, some examples of network devices 101 are: a general base station (gbb), a new radio Node B (NR-NB), a Transmission and Reception Point (TRP), an evolved Node B (eNB), a Radio Network Controller (RNC), a Node B (NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved Node B, HeNB; or home Node B, HNB), a Base Band Unit (BBU), or a wireless fidelity (Wifi) access point (access point, AP), or a network side device in a 5G communication system or a future possible communication system, etc.

The terminal 102, also referred to as User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (MT), etc., is a device that provides voice or data connectivity to a user, and may also be an internet of things device. For example, the terminal 102 includes a handheld device, a vehicle-mounted device, or the like having a wireless connection function. Currently, the terminal 102 may be: mobile phone (mobile phone), tablet computer, notebook computer, palm computer, Mobile Internet Device (MID), wearable device (e.g. smart watch, smart bracelet, pedometer, etc.), vehicle-mounted device (e.g. car, bicycle, electric car, airplane, ship, train, high-speed rail, etc.), Virtual Reality (VR) device, Augmented Reality (AR) device, wireless terminal in industrial control (industrial control), smart home device (e.g. refrigerator, television, air conditioner, electric meter, etc.), smart robot, workshop device, wireless terminal in self drive (driving), wireless terminal in remote surgery (remote medical supply), wireless terminal in smart grid (smart grid), wireless terminal in transportation safety (transportation safety), wireless terminal in smart city (city), or a wireless terminal in a smart home (smart home), a flying device (e.g., a smart robot, a hot air balloon, a drone, an airplane), etc.

The data channel in NR adopts pi/2-BPSK modulation and DFT-s-OFDM waveform, so that lower PAPR can be obtained and stronger applicability is realized. Especially for high frequency band, for example, above 52.6GHz, the power amplifier has poor performance and lower output power, so the waveform with low PAPR has stronger necessity. In order to fully exert the advantages of the DFT-s-OFDM waveform under pi/2-BPSK modulation, the design of the enhanced reference signal is designed, and the PAPR of the reference signal is close to or equal to the PAPR of the DFT-s-OFDM waveform of a data channel under pi/2-BPSK modulation.

It should be noted that the DFT-s-OFDM waveform is a single-carrier waveform, and the scheme designed in the present application can be applied to other single-carrier waveforms. Such as a UW-DFT-s-OFDM, ZT-DFT-s-OFDM waveform, or a time-domain shaped single carrier waveform. The scheme related to the application is not only suitable for uplink transmission, but also suitable for downlink transmission.

Part or all of the transmission method of the reference signal provided by the embodiment of the application can be executed by the network device and also can be executed by the terminal. In the following description, the execution main body is described with a first device and a second device. When the first equipment is network equipment, the second equipment is a terminal; or, when the first device is a terminal, the second device is a network device.

Based on the above description and the system architecture shown in fig. 1, as shown in fig. 2, the following describes in detail a transmission method of a reference signal provided in an embodiment of the present application.

The basic idea of the present application is to select a subsequence from a mother sequence, the length of the subsequence being the length of the reference signal, and the subsequence being the reference signal sequence. And processing the subsequence to obtain a reference signal, multiplexing the reference signal with a data channel, and sending the multiplexed signal. The detailed procedure is as follows, and in the following description, the parent sequence is represented by the first sequence and the child sequence by the second sequence. The reference signal may take DMRS as an example.

S201, the first device determines a second sequence d [ n ].

The second sequence d [ n ] is determined from the first sequence c [ m ], where m is 0,1, … …, K-1, i.e., c [ m ] has a length K. The second sequence is represented by dn, which is N in length. N, K is a positive integer. K is larger than or equal to N, and is generally far larger than N. The method for obtaining d [ n ] from c [ m ] can be referred to formula (1).

d[n]＝c[<n+n₀>_K]Formula (1)

Wherein N is 0,1, … …, N-1, N₀In order to be the value of the initial shift,<n+n₀>_Kdenotes n + n₀Modulo K, n₀Is a non-negative integer. This equation (1) can be illustrated in fig. 3, where a second sequence is generated by sliding from the left side with a bar of length N from the first sequence. The distance from the initial value of the sliding back strip block to the initial value of the first sequence is an initial shift value n₀. It can be seen that the second sequence can be composed of the first sequence and an initial shift value n₀To be determined. When the first sequence is determined, a different n is set₀A different second sequence may be obtained.

S202, the first equipment processes the second sequence to obtain a reference signal.

And S203, the first device multiplexes the reference signal and the data channel.

And S204, the first equipment sends the multiplexed signal to the second equipment.

In order to make the reference signal sequence closer to the frequency-domain constant modulus or flat sequence in the frequency domain, some existing sequences with better performance can be selected as the first sequence. Optionally, the first sequence is a Gold sequence.

When the reference signal is DMRS, the DMRS sequence length N in NR is related to the bandwidth used by the data channel. The data channels use different bandwidths, and the sequence lengths required for DMRSs are also different. In NR, a physical uplink/downlink shared channel (PUSCH/PDSCH) generally occupies a bandwidth of T Resource Blocks (RBs), and 1 RB includes 12 subcarriers. The number of sub-carriers occupied by the data channel is 12T, and T is a positive integer. For DMRS configuration of type 1(type 1), Resource Elements (REs) occupied by DMRSs are arranged in a comb shape in a frequency domain, the comb is 2, and a frequency domain pattern is shown in fig. 4. Wherein, the DMRS may be arranged at position 0 or position 1. Under DMRS configuration type 1, the DMRS sequence length is 6 × T, i.e., N — 6 × T. Of course, the DMRS may also adopt other configurations, and the length of the DMRS may also be other lengths, for example, 2T, 3T, or 12T.

The second sequence is obtained from the first sequence in order to match the length of the reference signal sequence. Since the length of the first sequence is generally not equal to the length of the second sequence. For example, a Gold sequence typically has a length of 2^ q-1, is odd in value, and cannot equal 6 ^ T.

In NR, the generation formula of Gold sequence is shown in formula (2).

In NR, Nc 1600, where x₁(n) has an initial value of x₁(0)＝1,x₁(n)＝0,n＝1,2,...,30，x₂(n) initialization parameters of

Random sequence c [ m ]]From an initialization parameter c_initDetermine, i.e. know, c_initA Gold sequence can be obtained.

At a known initialization parameter c_initWhile setting different initial shift values n₀A different second sequence is obtainedd[n]。

The first sequence may be a binary sequence, such as {0,1 }; the first sequence may also be a ternary sequence, such as 0,1, -1.

If the first sequence is a binary sequence, the second sequence obtained in S201 is also a binary sequence. In S202, the first device performs pi/2-BPSK modulation on the second sequence d [ N ] to obtain a time-domain reference signal sequence t [ N ] with a length of N.

If the second sequence is a ternary sequence, the second sequence obtained in S201 is also a ternary sequence. In S202, the first device performs memory phase modulation on the second sequence d [ N ], to obtain a time-domain reference signal sequence t [ N ] with a length N.

Specifically, the ternary sequence d [ n ] is converted to t [ n ] in the following manner:

t[0]is exp (-j theta0 d [0]]) Where theta0 is the initial phase and j is an imaginary symbol, i.e.

And t [ n ] ═ t [ n-1 ]. exp (-j. theta 1. d [ n ]), wherein theta1 is the transition unit phase.

As shown in FIG. 5, a simple example is that theta1 is pi/2. When d [ n ] is 0, t [ n ] is equal to t [ n-1 ]; when d [ n ] is 1, t [ n ] is obtained by rotating t [ n-1] by pi/2; and when d [ n ] ═ 1, t [ n ] is obtained by rotating t [ n-1] by-pi/2.

The maximum phase change of the ternary sequence is pi/2, so that the PAPR performance can be good. The phase theta0 d0 has no influence on the PAPR and frequency domain flatness, so the product of the two can be made to take an arbitrary value. For example, the protocol specifies theta0 ═ 0, d [0] ═ 1, theta0 ═ d [0] ═ pi/2, and the like. When theta0 × d [0] is defined as pi/2, theta0 varies with d [0 ].

In one possible design (denoted as design 1), after a time-domain reference signal sequence t [ n ] is obtained, DFT transformation is performed on t [ n ] to obtain a frequency-domain reference signal sequence f [ n ], and further a reference signal is obtained. The reference signal is multiplexed with the data channel in S203, and the multiplexed signal is transmitted after a series of processes. The series of processing may include frequency domain resource mapping, Inverse Fast Fourier Transformation (IFFT), Cyclic Prefix (CP) addition, Digital Analog Converter (DAC), and the like. The manner of obtaining the time-domain reference signal sequence t [ n ] may include the above two modulation and/or processing methods.

In another possible design (denoted as design 2), after obtaining the time-domain reference signal sequence t [ n ], multiplexing a reference signal obtained by the time-domain reference signal sequence t [ n ] with a data channel, and sending the multiplexed signal after a series of processing, where the series of processing may include performing DFT transform, frequency-domain resource mapping, IFFT, adding CP or DAC on the multiplexed signal, and the like. The method for obtaining the time-domain reference signal sequence t [ n ] may include the above two modulation methods.

Under a specific application scenario, the possible flows in the above two designs are shown in fig. 6a and 6 b.

As shown in fig. 6a, after being modulated, the coded data bits are DFT-transformed, multiplexed with the DFT-transformed reference signal sequence, and then sent after being subjected to frequency domain resource mapping, IFFT, CP addition, and DAC addition.

As shown in fig. 6b, the encoded data bits are modulated, multiplexed with the reference signal sequence, and then sent after DFT conversion, frequency domain resource mapping, IFFT, CP and DAC addition after multiplexing.

As can be seen from the above, the reference signal sequence in the time domain is obtained first, the reference signal sequence in the frequency domain is obtained after the time-frequency domain conversion, and the reference signal is generated and sent. The reference signal sequence in the time domain is easier to achieve the low PAPR requirement. For example, the same PAPR as data modulated by pi/2-BPSK can be obtained by pi/2-BPSK modulation of the binary sequence {0,1} reference signal sequence as described above.

Furthermore, in order to enable the time domain reference signal to have better frequency domain flatness after being converted into the frequency domain reference signal, and thus to ensure better channel estimation performance, the method for obtaining the sequence with better frequency domain flatness performance is designed on the basis of selecting some existing sequences such as Gold sequences. The specific method is as follows.

As can be seen from the above description, when the length N of the second sequence is known, the second sequence is determined by the first sequence (mother sequence) and the initial shift value. The set of sequences whose frequency domain is flat can be searched out by a computer. The search optimization criteria is not limited in this application, and for example, the search may be performed by using a criterion that maximizes the lowest power in the frequency domain. The search may be performed in such a manner that the first sequence is fixed and the initial shift is transformed, or in such a manner that both the first sequence and the initial shift are transformed. For different lengths N, a search is performed. In one possible design, there are several candidate sequences and several candidate initial shift values, for example, there are M candidate sequences and O candidate initial shift values, M, O being positive integers. The network device selects a first sequence c M from the M candidate sequences]An initial shift value n0 is selected from the O candidate initial shift values. The network device selects a first sequence c m]And information of selecting the initial shift value n0 is transmitted to the terminal. In the flow shown in fig. 2, in a scenario where the first device is a network device and the second device is a terminal, the first device executes an operation of the network device; and when the first device is a terminal and the second device is a network device, the first device executes the operation of the terminal. Optionally, c [ m ]]Information that c [ m ] can be decided]Any of (1). For example, c [ m ]]For a Gold sequence, as shown in equation (2), a Gold random sequence c [ m ]]From an initialization parameter c_initDetermine, then c [ m ]]May be the initialization parameter c_init. The terminal can be based on the initialization parameter c_initTo determine a first sequence c m]. In NR, there are

Thus c_initHas a value range of 0,1,2, …,2³¹-1. In one implementation, the network device notifies c directly to the terminal_init. In another possible implementation, the network device informs the terminal of a parameter, from which the terminal deduces c, based on rules defined by the protocol_init. For example, protocol specification c_init＝<c0+c1>_ZWherein Z is 2³¹C0 is a general terminalThe values obtained by the protocol specification rules, and c1 are the values configured by the network device for the terminal. Optionally, c the network device can notify_initThe range being less than its maximum possible value, e.g. c, which specifies that the network device can notify_initOr c1 is selected from the range of 0,1,2, …, Z1, wherein Z1 is<2³¹-1。

Initial shift value n₀Is used to indicate the initial shift value n₀. For example, the network device indicates n directly₀Is given by the value of (a), wherein n₀Is in the range of 0,1,2, …, K-1, wherein K is c [ m ]]Length of (d). Optionally, n that the network device can notify₀The range being less than its maximum possible value, e.g. n, which a network device can notify₀Has a value range of 0,1,2, …, K1, wherein K1<K. Optionally, n₀The DMRS sequence may be fixed value, e.g., 0, i.e., the network device and/or protocol selects the DMRS sequence only through initialization parameters.

Optionally, when the lengths of the second sequences are different, the network device notifies the terminal of different information of the first sequence and information of the initial shift value. In one possible implementation, the network device notifies information of the corresponding first sequence and information of the initial shift value under a plurality of N values. For example, the value of notification N may be 36, 48, 60, or 72. Optionally, the value of N should satisfy the condition N ═ 6 × 2^α2*3^α3*5^α5Wherein, alpha 2, alpha 3 and alpha 5 are nonnegative integers. The value of N is limited because the number of distributable PRBs of DFT-s-OFDM waveform in NR needs to be equal to 2^α2*3^α3*5^α5. In one possible implementation, the network device does not configure the information of the first sequence and the information of the initial shift value for all possible N values. For example, when N is 120, that is, when the corresponding bandwidth is 20RB, the network device does not configure the information of the corresponding first sequence and the information of the initial shift value. There are two options at this time: 1. the terminal does not want to be configured with DFT-s-OFDM waveform and pi/2-BPSK modulation when scheduling 20 RBs; 2. when the above scheduling occurs, the terminal assumes that the DMRS sequence employs a ZC sequence or the remaining sequences.

The information of the first sequence and the information of the initial shift value may be notified by the network device through RRC or MAC CE signaling. In one possible implementation, if the terminal adopts an existing ZC sequence as the DMRS sequence before the terminal receives no configuration as described above.

The initialization parameter and the initial shift configuration method of the present invention are specifically described below with reference to the initialization parameter of the NR existing DMRS. In NR, the initialization parameters of DMRS are:

wherein the content of the first and second substances,

indicates the number of symbols in one slot,

is the slot number within the radio frame, l is the symbol number within OFDM, n_SCID∈{0,1}，n_SCIDThe specific value of (a) is determined by a Downlink Control Information (DCI) format and/or DCI content.

There are many possible values, e.g.

May be equal to the physical cell ID, or to the RRC configuration value (scramblingID 0 and scramblingID1, respectively, corresponding to different n_SCIDValue taking). In equation (3) (. g) mod2³¹For modular operation, as described above

And equivalence. Although existing DMRS sequences may be part of the initialization parameters configured by RRC signaling (i.e.

) However, since the initialization parameter also includes the timeslot and symbol number, the initialization parameter changes at different timesIn (1). If the existing generation method of the initialization parameters is applied to the generation of the pi/2-BPSK time domain DMRS, the DMRS sequences are different at different moments, and the DMRS sequences at some moments have poor frequency domain flatness, so that the demodulation performance is reduced.

In order to solve the above problem, in the solution of the present application, the initialization parameter does not include a timeslot number and a symbol number, so the network device may select a sequence with better performance and send the initialization parameter or a part of the initialization parameter to the terminal, and the initialization parameter may also be associated with a physical cell ID, so that the initialization parameter configurable for different cells can be associated, thereby achieving the purpose of randomizing interference. For DMRS sequences of different lengths, there are the following options, all implemented by configuration or by protocol definition: 1. different length DMRS sequences are configured with different initialization parameters, and the initial shift values are the same; 2. configuring the same initialization parameters and different initial shift values for the DMRS sequences with different lengths; 3. different length DMRS sequences are configured with different initialization parameters and different initial shift values.

In another possible design, L possible second sequences are pre-selected for a plurality of N, i.e. for a plurality of possible DMRS sequence lengths, L being a positive integer, e.g. L ═ 30. Each possible second sequence consists of a first sequence c m]And initial shift value n₀The information of (3) determines that the L possible second sequences are indexed by sequence numbers. The L possible second sequences are predetermined, specified by the protocol or configured for the terminal by the network device. If the L possible sequences are configured by the network device, the configuration process is as described above. Thus, both the network device and the terminal can determine the sequence number first and obtain the indexed first sequence c [ m ] according to the sequence number]And an initial shift value n₀。

L first sequences c [ m ]]And L initial shift values n₀Has a one-to-one correspondence relationship. Sequence numbering, c [ m ] for a bandwidth or a reference signal sequence length N]And n₀The relationship of (a) can be illustrated by table 1. Sequence numbers 0, …, L, first sequence c [ m]Is represented by X (0), …, X (L-1), the initial shift n₀N for information of₀(0)、…、n₀(L-1). Some other optional parameters related to the sequence, denoted by Y (0), …, Y (L-1), may also be included in the table.

TABLE 1

Sequence numbering	Information of the first sequence	Information of initial shift	Others (optional)
				0	X(0)	n₀(0)	Y(0)
…	…	…	…
				L-1	X(L-1)	n₀(L-1)	Y(L-1)

Assume that the second sequence of length N has 30 possibilities, 30 first sequences c m]And 30 initial shift values n₀Has one-to-one correspondence relationship, sequence number, c [ m ]]And n₀The relationship of (c) can be illustrated by table 2. Sequence numbers 0, …L, a first sequence c [ m ]]Is c [ m ] as information of]Initialization parameter c of_init. 30 pieces of c [ m ]]Is represented by X (0), …, X29), 30 initial shifts n₀N for information of₀(0)、…、n₀(29) To indicate. Some other optional parameters related to the sequence, denoted Y (0), …, Y (29), may also be included in the table.

TABLE 2

Sequence numbering	Parent sequence identification	Initial shift (n)₀)	Others (optional)
				0	c_init(0)	n₀(0)	Y(0)
…	…	…	…
				L-1	c_init(29)	n₀(29)	Y(29)

Table 1 and table 2 show sequence parameters for one bandwidth or one reference signal sequence length. In practical applications, sequence parameters under various bandwidths or various reference signal sequence lengths can be represented by one table, or sequence parameters under various bandwidths or various reference signal sequence lengths can be represented by a plurality of tables.

When the terminal has the capability of supporting the reference signal sequence related to the application, the terminal reports the capability to the network equipment, and the network equipment determines whether the terminal supports the capability according to the report of the terminal.

When the scheme of the embodiment is applied to uplink, the terminal transmits the DMRS of the PUSCH or the PUCCH by using the second sequence. When the scheme of this embodiment is applied to downlink, the terminal receives the DMRS of the PDSCH or the PDCCH by using the second sequence.

It should be noted that although the embodiments of the present application take demodulation reference signals (DMRS) as an example for description, the scheme may also be used for other reference signals, such as channel state information-reference signals (CSI-RS).

In S203, the first device multiplexes the reference signal and the data channel, and optionally, a multiplexing method is further designed in this application.

Usually, the reference signal symbol and the data modulation symbol are independent symbols, and in some cases, the load of the data channel is small enough not to support transmission of one slot, for example, the data amount of the terminal only supports 1 or 2 symbols. When the data volume of the terminal supports 1 symbol, the data cannot be transmitted; when the data amount of the terminal supports 2 symbols, 1 symbol is a reference signal symbol, and 1 symbol is a data modulation symbol, a separate reference signal will cause excessive overhead. In order to support the transmission of a single-carrier symbol in a single symbol provided by the application, the application relates to a multiplexing method of a data channel and a reference signal in the single symbol.

As shown in FIG. 7, the single symbol may be referred to as a single OFDM or DFT-s-OFDM symbol that includes both reference signal symbols and data modulation symbols. The reference signal may be a DMRS, and the DMRS symbol may be understood as a self-contained DMRS (self-contained DMRS).

The multiplexing method is suitable for the design 2 above, i.e. the process of multiplexing and then performing DFT transform. Optionally, the flow of fig. 6b may be referred to.

For design 2 of the transmitting end, as shown in fig. 8, the present application also designs a receiver scheme. The receiver demaps the reference signal before FFT and then performs FFT independently. The FFT is followed by channel estimation, equalization, and Inverse Discrete Fourier Transform (IDFT).

In order to make the reference signal FFT power-of-2 independent, design 2 reference signal length is 1/2 of one OFDM or DFT-s-OFDM symbol length^mAnd m is a non-negative integer. For example, the reference signal length for design 2 is 1/2, 1/4, 1/8, etc., of one OFDM or DFT-s-OFDM symbol length. Here, neither the reference signal length nor the OFDM or DFT-s-OFDM symbol length includes the CP length. For DFT-s-OFDM waveform, assuming that the DFT order at the transmitting end is Nsc, the length of the reference signal before DFT is Nsc/2^mFor example, when the DFT order is 1200(100 RBs), the length of the reference signal may be 600 or 300. It should be noted that the length of the above-mentioned reference signal does not include a possible prefix or suffix length. Optionally, before DFT, a time domain start position of the DMRS in the OFDM or DFT-s-OFDM symbol is k × Nsc/2^m. Wherein k is 0,1, …,2^m-1.

For example, when the FFT length of the data is 2048 and the reference signal length is 1/4 of one OFDM symbol length, the FFT length of the reference signal is 512. The reference signal of design 2 may have a prefix and/or a suffix of the sequence, as shown in fig. 7. The length of the prefix and/or suffix may not be fixed, for example, there may be a plurality of choices, and the upper node configures one of the lengths. In a possible implementation manner, the terminal reports the prefix and/or suffix length required by the terminal, and the network device performs prefix and suffix length configuration according to the reported value. Wherein the prefix and suffix include a cyclic prefix and a cyclic suffix.

Based on the same inventive concept, as shown in fig. 9, an embodiment of the present application further provides a reference signal transmission apparatus 900, where the reference signal transmission apparatus 900 is applicable to the communication system shown in fig. 1, and performs the function of the first device in the above method embodiment. When the first device is a terminal, the transmission apparatus 900 for the reference signal is applied to the terminal or is the terminal; when the first device is a network device, the apparatus 900 for transmitting the reference signal is applied to the network device or the network device.

The apparatus 900 for transmitting reference signals includes a processing unit 901 and a transmitting unit 902. The processing unit 901 is configured to determine a second sequence d [ n ], process the second sequence to obtain a reference signal, and multiplex the reference signal with a data channel. A sending unit 902, configured to send the signal multiplexed by the processing unit 901 to the second device.

Optionally, the processing unit 901 is further configured to determine a first sequence c [ m ]]And n is₀The information of (1). After determining the second sequence d [ n ]]The processing unit 901 is specifically configured to perform the processing according to a first sequence c m]And n is₀Determines the second sequence d [ n ]]。

The processing unit 901 is further configured to determine a sequence number (which may be simply referred to as a number), and determine a first sequence c [ m ] indexed by the sequence number]And n₀。

When the transmission apparatus 900 of the reference signal is a network device and the second device is a terminal, the sending unit 902 is further configured to send the first sequence c [ m ] to the second device]And n is₀The information of (a); alternatively, the first device sends a first sequence c [ m ] to the second device]The information of (a); or the first device sends information of the number to the second device, wherein the number is used for indicating the first sequence c [ m ]]And n is₀The information of (1).

Specifically, the processing unit 901 selects a first sequence c [ M ] from the M candidate sequences]Selecting n from the O candidate initial shift values₀M, O is a positive integer; transmitting section 902 transmits first sequence c m]And n is₀Is sent to the second device.

When the apparatus 900 for transmitting a reference signal is a terminal and the second device is a network device, the apparatus for transmitting a reference signal further includes: a receiving unit 903 for receiving the data from the secondThe device receives a first sequence c m]And n is₀The information of (a); alternatively, the first device receives the first sequence c [ m ] from the second device]The information of (a); alternatively, the first device receives information of a number indicating the first sequence c m from the second device]And n is₀The information of (1).

The processing unit 901 is further configured to carry the data modulation symbols and the reference signal in OFDM symbols.

Based on the same inventive concept as the above communication method, as shown in fig. 10, an embodiment of the present application further provides a transmission apparatus 1000 for a reference signal, where the communication apparatus 1000 includes: transceiver 1001, processor 1002, memory 1003. The memory 1003 is optional. The memory 1003 is used for storing programs executed by the processor 1002. When the communication apparatus 1000 is used to implement the operations performed by the first device in the above method embodiments, the processor 1002 is configured to call a set of programs, and when the programs are executed, the processor 1002 is configured to perform the operations performed by the first device in the above method embodiments. The functional modules in fig. 9, the transmitting unit 902 and the receiving unit 903, may be implemented by a transceiver 1001, and the processing unit 901 may be implemented by a processor 1002.

The processor 1002 may be a Central Processing Unit (CPU), a Network Processor (NP), or a combination of the CPU and the NP.

The processor 1002 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a Programmable Logic Device (PLD), or a combination thereof. The PLD may be a Complex Programmable Logic Device (CPLD), a field-programmable gate array (FPGA), a General Array Logic (GAL), or any combination thereof.

The memory 1003 may include a volatile memory (volatile memory), such as a random-access memory (RAM); the memory 1003 may also include a non-volatile memory (non-volatile memory), such as a flash memory (flash memory), a Hard Disk Drive (HDD) or a solid-state drive (SSD); the memory 1003 may also include a combination of the above types of memories.

In the transmission method of the reference signal provided in the above embodiments of the present application, some or all of the operations and functions performed by the first device and the second device described above may be implemented by a chip or an integrated circuit.

In order to implement the functions of the apparatus described in fig. 9 or fig. 10, an embodiment of the present application further provides a chip, which includes a processor, and the transmission apparatus 900 for supporting the reference signal and the transmission apparatus 1000 for the reference signal implement the functions related to the terminal and the network device in the method provided in the foregoing embodiment. In one possible design, the chip is connected to or includes a memory for storing the necessary program instructions and data for the device.

The embodiment of the application provides a computer storage medium, which stores a computer program, wherein the computer program comprises instructions for executing the transmission method of the reference signal provided by the embodiment.

The embodiments of the present application provide a computer program product containing instructions, which when run on a computer, cause the computer to execute the transmission method of the reference signal provided by the above embodiments.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While the preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various changes and modifications may be made in the embodiments of the present application without departing from the spirit and scope of the embodiments of the present application. Thus, if such modifications and variations of the embodiments of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to encompass such modifications and variations.

Claims

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

the first device determines a second sequence d n]Wherein, in the step (A),

，n=0、1、……、N-1，n₀in order to be the value of the initial shift,

to represent

Modulo K, n₀Is a non-negative integer, c [ m ]]Is a first sequence, said first sequence c [ m ]]The sequence is a Gold sequence, m =0, 1, … … and K-1, K is more than or equal to N, and N, K is a positive integer;

the first equipment processes the second sequence to obtain a reference signal;

and the first equipment multiplexes the reference signal and a data channel and sends the multiplexed signal to the second equipment.

2. The method of claim 1, wherein the method further comprises: the first device determines the first sequence c [ m ]]And said n₀The information of (a);

said first device determining said second sequence d [ n ], comprising:

the first device according to the first sequence c [ m ]]And said n₀Determines the second sequence d [ n ]]。

3. The method of claim 2, wherein the first device is a network device and the second device is a terminal, the method further comprising:

the first device sends the first sequence c [ m ] to the second device]And said n₀The information of (a); alternatively, the first and second electrodes may be,

the first device sending information of the first sequence c [ m ] to the second device; alternatively, the first and second electrodes may be,

the first device sends information of a number to the second device, wherein the number is used for indicating the first sequence c [ m ]]And said n₀The information of (1).

4. The method of claim 2, wherein the first device is a terminal and the second device is a network device, the method further comprising:

the first device receives the first sequence c [ m ] from the second device]And said n₀The information of (a); alternatively, the first and second electrodes may be,

the first device receiving the first sequence of information c [ m ] from the second device; alternatively, the first and second electrodes may be,

the first device receives information of a number indicating the first sequence c [ m ] from the second device]And said n₀The information of (1).

5. A method according to any of claims 2 to 4, wherein the information of the first sequence c [ m ] is an initialization parameter of c [ m ].

6. The method of any one of claims 1 to 4, wherein the first sequence is a binary sequence or a ternary sequence.

7. The method of any of claims 1 to 4, wherein the first device processes the second sequence, comprising:

the first sequence is a binary sequence, and the first device performs pi/2-binary phase shift keying BPSK modulation on the second sequence; alternatively, the first and second electrodes may be,

the first sequence is a ternary sequence, and the first device performs memory phase modulation on the second sequence.

8. The method of any of claims 1-4, wherein the first device multiplexing the reference signal with a data channel, comprises:

the first device carries data modulation symbols and the reference signal in OFDM symbols.

9. The method of claim 8, wherein the reference signal occupies 1/2 the length of one of the OFDM symbols^mAnd m is a non-negative integer.

10. A method according to any one of claims 1 to 4, wherein N is related to the data channel bandwidth.

11. An apparatus for transmitting a reference signal, comprising:

a processing unit for determining a second sequence d [ n ]]Wherein, in the step (A),

，n=0、1、……、N-1，n₀in order to be the value of the initial shift,

to represent

the processing unit is further configured to process the second sequence to obtain a reference signal; and for multiplexing the reference signal with a data channel;

and the sending unit is used for sending the signal multiplexed by the processing unit to the second equipment.

12. The apparatus as recited in claim 11, said processing unit to further: determining the first sequence c [ m ]]And said n₀The information of (a);

after determining the second sequence d [ n ]]The processing unit is configured to: according to said first sequence c [ m ]]And said n₀Determines the second sequence d [ n ]]。

13. The apparatus of claim 12, wherein the apparatus is a network device and the second device is a terminal;

the transmitting unit is further configured to transmit the first sequence c [ m ] to the second device]And said n₀The information of (a); alternatively, the first and second electrodes may be,

sending information of the first sequence c [ m ] to the second device; alternatively, the first and second electrodes may be,

sending information of a number to the second device, the number indicating the first sequence c [ m ]]And said n₀The information of (1).

14. The apparatus of claim 12, wherein the apparatus is a terminal, wherein the second device is a network device, and wherein the apparatus further comprises a receiving unit configured to:

receiving the first sequence c [ m ] from the second device]And said n₀The information of (a); alternatively, the first and second electrodes may be,

receiving information of the first sequence c [ m ] from the second device; alternatively, the first and second electrodes may be,

receiving information of a number indicating the first sequence c [ m ] from the second device]And said n₀The information of (1).

15. The apparatus according to any one of claims 12 to 14, wherein the information of the first sequence c [ m ] is an initialization parameter of c [ m ].

16. The apparatus of any one of claims 11 to 14, wherein the first sequence is a binary sequence or a ternary sequence.

17. The apparatus according to any of claims 11 to 14, wherein the first sequence is a binary sequence, and the processing unit is configured to perform pi/2-binary phase shift keying BPSK modulation on the second sequence; alternatively, the first and second electrodes may be,

the first sequence is a ternary sequence, and the processing unit is used for carrying out memory phase modulation on the second sequence.

18. The apparatus of any of claims 11-14, wherein the processing unit is further configured to carry data modulation symbols and the reference signal in the OFDM symbol.

19. The apparatus of claim 18, wherein the reference signal occupies 1/2 a length of the one OFDM symbol in the one OFDM symbol^mAnd m is a non-negative integer.

20. The apparatus of any of claims 11-14, wherein N is related to a data channel bandwidth.

21. An apparatus for transmitting a reference signal, comprising:

a memory for storing a program;

a processor for executing the program stored in the memory, the processor being configured to perform the method of any of claims 1-10 when the program is executed.

22. The apparatus of claim 21, wherein the means for transmitting the reference signal is a chip or an integrated circuit.

23. A computer-readable storage medium having computer-readable instructions stored thereon which, when read and executed by a computer, cause the computer to perform the method of any one of claims 1-10.