Inter-flow interference elimination method and device and storage medium

Abstract

The invention relates to an inter-flow interference elimination method and device and a storage medium. The method comprises the following steps: acquiring a least square error (LS) channel estimation result of each subcarrier on a pilot frequency; determining a phase offset estimation result according to the LS channel estimation result of each subcarrier; determining channel time delay based on a phase offset estimation result; performing phase compensation on the LS channel estimation result of each subcarrier based on the phase offset estimation result to obtain the compensated LS channel estimation result of each subcarrier; and inter-stream interference elimination is carried out based on the compensated LS channel estimation result of each subcarrier and the channel time delay. By adopting the method, the uplink signal demodulation performance can be improved.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and in particular, to an inter-stream interference cancellation method, apparatus, and storage medium. Background Art

[0002] In a 5G communication system, the performance of the base station side Physical Uplink Shared Channel (PUSCH) estimation directly affects the demodulation performance and results of the uplink signal. For example, when the channel delay is large, the channel estimation result is affected, resulting in a decrease in the uplink demodulation performance.

[0003] In traditional technologies, during the PUSCH channel estimation process, the Sounding Reference Signal (SRS) is used to calculate the Impulse Response Timing (IRT), and then the calculated IRT is used for inter-stream interference cancellation.

[0004] However, the SRS is a periodic signal, which is different from the content, frequency domain bandwidth, and time domain position of the PUSCH transmission, resulting in poor demodulation performance of the uplink signal. Summary of the Invention

[0005] Based on this, it is necessary to provide an inter-stream interference cancellation method, apparatus, and storage medium for the above technical problems.

[0006] In a first aspect, this application provides an inter-stream interference cancellation method, which includes:

[0007] Obtain the least squares (LS) channel estimation results of each subcarrier on the pilot;

[0008] Determine the phase deviation estimation result according to the LS channel estimation results of each subcarrier;

[0009] Determine the channel delay based on the phase deviation estimation result;

[0010] Perform phase compensation on the LS channel estimation result of each subcarrier based on the phase deviation estimation result to obtain the compensated LS channel estimation result of each subcarrier;

[0011] Perform inter-stream interference cancellation based on the compensated LS channel estimation results of each subcarrier and the channel delay.

[0012] In a possible implementation, the pilot includes L subcarriers, where L is a positive integer. The step of determining the phase deviation estimation result according to the LS channel estimation results of each subcarrier includes:

[0013] Determine the k-th subcarrier and the (k + δ)-th subcarrier as a pair of sampled adjacent subcarriers, where 0 ≤ k ≤ L - δ - 1, k and δ are integers, and δ represents the offset between a pair of sampled adjacent subcarriers;

[0014] Perform a conjugate multiplication operation on the LS channel estimation result of the k-th subcarrier and the LS channel estimation result of the (k + δ)-th subcarrier to obtain the conjugate multiplication result of a pair of sampled adjacent subcarriers;

[0015] Perform an accumulation operation and a normalization process on the conjugate multiplication results of each pair of sampled adjacent subcarriers to obtain the phase offset estimation result.

[0016] In a possible implementation, the method further includes:

[0017] Determine the product of the number of resource blocks on the pilot and the number of subcarriers in each resource block as the number of subcarriers on the pilot.

[0018] In a possible implementation, step of determining the channel delay based on the phase offset estimation result includes:

[0019] Determine the channel delay according to the phase offset estimation result and the preset number of sampling points.

[0020] In a possible implementation, step of determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes:

[0021] Determine the ratio of the imaginary part to the real part of the phase offset estimation result;

[0022] Multiply the preset number of sampling points by the arctangent operation result of the ratio to obtain a first product;

[0023] Determine the channel delay according to the ratio of the first product to the offset between a pair of sampled adjacent subcarriers.

[0024] In a possible implementation, step of determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes:

[0025] Determine the phase angle according to the phase offset estimation result;

[0026] Multiply the preset number of sampling points by the phase angle to obtain a second product;

[0027] Determine the channel delay according to the ratio of the second product to the offset between a pair of sampled adjacent subcarriers.

[0028] In a possible implementation, step of performing phase compensation on the LS channel estimation result of each subcarrier based on the phase offset estimation result to obtain the compensated LS channel estimation result of each subcarrier includes:

[0029] Determine the phase angle according to the phase deviation estimation result;

[0030] Perform phase compensation on the LS channel estimation result of each subcarrier using the phase angle to obtain the LS channel estimation result after compensation for each subcarrier.

[0031] In a possible implementation, performing phase compensation on the LS channel estimation result of each subcarrier using the phase angle to obtain the LS channel estimation result after compensation for each subcarrier includes:

[0032] Construct an intermediate result with the cosine value of the phase angle as the real part and the sine value of the phase angle as the imaginary part;

[0033] Multiply the LS channel estimation result of each subcarrier by the intermediate result to obtain the LS channel estimation result after compensation for each subcarrier.

[0034] In a second aspect, the present application also provides an inter-stream interference cancellation device, which includes:

[0035] An acquisition unit, configured to acquire the least squares (LS) channel estimation results of each subcarrier on the pilot;

[0036] A first determination unit, configured to determine the phase deviation estimation result according to the LS channel estimation results of each subcarrier;

[0037] A second determination unit, configured to determine the channel time delay based on the phase deviation estimation result;

[0038] A compensation unit, configured to perform phase compensation on the LS channel estimation result of each subcarrier based on the phase deviation estimation result to obtain the LS channel estimation result after compensation for each subcarrier;

[0039] An elimination unit, configured to perform inter-stream interference cancellation based on the LS channel estimation results after compensation for each subcarrier and the channel time delay.

[0040] In a possible implementation, there are L subcarriers on the pilot, L is a positive integer, and the first determination unit is further configured to:

[0041] Determine the k-th subcarrier and the (k + δ)-th subcarrier as a pair of sampled adjacent subcarriers, where 0 ≤ k ≤ L - δ - 1, k and δ are integers, and δ represents the offset between a pair of sampled adjacent subcarriers;

[0042] Perform a conjugate multiplication operation on the LS channel estimation result of the k-th subcarrier and the LS channel estimation result of the (k + δ)-th subcarrier to obtain the conjugate multiplication result of a pair of sampled adjacent subcarriers;

[0043] Perform an accumulation operation and a normalization process on the conjugate multiplication results of each pair of sampled adjacent subcarriers to obtain the phase deviation estimation result.

[0044] In a possible implementation, the apparatus further includes:

[0045] A third determining unit, configured to determine the number of subcarriers on the pilot as the product of the number of resource blocks on the pilot and the number of subcarriers in each resource block.

[0046] In a possible implementation, the second determining unit is further configured to:

[0047] Determine the channel delay according to the phase offset estimation result and the preset number of sampling points.

[0048] In a possible implementation, determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes:

[0049] Determine the ratio of the imaginary part to the real part of the phase offset estimation result;

[0050] Multiply the preset number of sampling points by the arctangent operation result of the ratio to obtain a first product;

[0051] Determine the channel delay according to the ratio of the first product to the offset between a pair of adjacent sampled subcarriers.

[0052] In a possible implementation, determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes:

[0053] Determine the phase angle according to the phase offset estimation result;

[0054] Multiply the preset number of sampling points by the phase angle to obtain a second product;

[0055] Determine the channel delay according to the ratio of the second product to the offset between a pair of adjacent sampled subcarriers.

[0056] In a possible implementation, the compensation unit is further configured to:

[0057] Determine the phase angle according to the phase offset estimation result;

[0058] Perform phase compensation on the LS channel estimation result of each subcarrier using the phase angle to obtain the compensated LS channel estimation result of each subcarrier.

[0059] In a possible implementation, performing phase compensation on the LS channel estimation result of each subcarrier using the phase angle to obtain the compensated LS channel estimation result of each subcarrier includes:

[0060] Construct an intermediate result with the cosine value of the phase angle as the real part and the sine value of the phase angle as the imaginary part;

[0061] Multiply the LS channel estimation results of each subcarrier by the intermediate results to obtain the compensated LS channel estimation results for each subcarrier.

[0062] In a third aspect, the present application also provides an inter-stream interference cancellation device, including a memory, a transceiver, and a processor:

[0063] The memory is used to store computer programs; the transceiver is used to transmit and receive data under the control of the processor; the processor is used to read the computer programs in the memory and perform the following operations:

[0064] Obtain the least squares (LS) channel estimation results of each subcarrier on the pilot;

[0065] Determine the phase offset estimation result according to the LS channel estimation results of each subcarrier;

[0066] Determine the channel delay based on the phase offset estimation result;

[0067] Perform phase compensation on the LS channel estimation results of each subcarrier based on the phase offset estimation result to obtain the compensated LS channel estimation results for each subcarrier;

[0068] Perform inter-stream interference cancellation based on the compensated LS channel estimation results of each subcarrier and the channel delay.

[0069] In a fourth aspect, the present application also provides a processor-readable storage medium, on which a computer program is stored. When the computer program is executed by the processor, it implements any one of the inter-stream interference cancellation methods in the first aspect above.

[0070] In a fifth aspect, the present application also provides a computer program product, including a computer program. When the computer program is executed by the processor, it implements any one of the inter-stream interference cancellation methods in the first aspect above.

[0071] For the above inter-stream interference cancellation method, device, and storage medium, according to the least squares channel estimation results of each subcarrier on the pilot, determine the phase offset estimation result, perform phase compensation on the least squares channel results of each subcarrier according to the phase offset estimation result, and determine the channel delay according to the phase offset estimation result, so as to perform inter-stream interference cancellation according to the compensated least squares channel results of each subcarrier and the channel delay. In this way, on the one hand, by determining the channel delay based on the phase offset estimation result, the accuracy of the channel delay is improved; on the other hand, by combining phase offset compensation and channel delay for inter-stream interference cancellation, the anti-interference effect against large delays in the signal transmission process is enhanced. Therefore, the performance of channel estimation is strongly enhanced, thereby improving the uplink signal demodulation performance. Description of the Drawings

[0072] To more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the accompanying drawings required for the description of the embodiments or related technologies. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0073] Figure 1 It is an application environment diagram of the inter-stream interference cancellation method in an embodiment;

[0074] Figure 2 It is a schematic flowchart of the inter-stream interference cancellation method in an embodiment;

[0075] Figure 3 It shows a schematic architecture diagram of the inter-stream interference cancellation system provided by the embodiments of the present application;

[0076] Figure 4 It shows a structural block diagram of the inter-stream interference cancellation device provided by the embodiments of the present application;

[0077] Figure 5 It is an internal structure diagram of the inter-stream interference cancellation device in an embodiment. Detailed implementation manners

[0078] In the embodiments of the present invention, the term "and / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0079] In the embodiments of the present application, the term "a plurality of" means two or more, and other quantifiers are similar.

[0080] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0081] The embodiments of the present application provide an inter-stream interference cancellation method and device. On the one hand, by determining the channel delay based on the phase offset estimation result, the accuracy of the channel delay is improved; on the other hand, by combining phase offset compensation and channel delay for inter-stream interference cancellation, the performance of channel estimation is enhanced, and thus the performance of uplink signal demodulation is improved. Among them, the method and the device are based on the same inventive concept. Since the principles for solving problems by the method and the device are similar, the implementation of the device and the method can be referred to each other, and the repeated parts will not be elaborated.

[0082] In an exemplary embodiment, the inter-stream interference cancellation method provided by the embodiments of the present application can be applied to an application environment as Figure 1 shown. Among them, data communication is performed between the terminal device 100 and the network device 200 through a wireless system.

[0083] The technical solutions provided by the embodiments of the present application can be applicable to a variety of systems. For example, the applicable systems can be a Long Term Evolution (LTE) system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD) system, a Long Term Evolution Advanced (LTE-A) system, a Universal Mobile Telecommunications System (UMTS), a Worldwide Interoperability for Microwave Access (WiMAX) system, a 5G New Radio (NR) system and its evolved communication systems, etc. These various systems may include terminal devices and network devices. The system may also include a core network part, such as an Evolved Packet System (EPS), a 5G System (5GS), etc.

[0084] The terminal device involved in the embodiments of the present application can be a device that provides voice and / or data connectivity to users, such as a handheld device with wireless connection capabilities, or other processing devices connected to a wireless modem, etc. In different systems, the name of the terminal device may also be different. For example, in a 5G system, the terminal device can be called a User Equipment (UE). The wireless terminal device can be a USB storage device, other personal computer memory devices, and dongles, and can also communicate with one or more core networks (CN) via a Radio Access Network (RAN). The wireless terminal device can be a mobile terminal device, such as a mobile phone (or a "cellular" phone) and a computer with a mobile terminal device. For example, it can be a portable, pocket-sized, handheld, computer-integrated, or vehicle-mounted mobile device that exchanges voice and / or data with the wireless access network. For example, devices such as Personal Communication Service (PCS) phones, cordless phones, Session Initiated Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDA), personal computers, tablets, Machine-type Communication (MTC) terminal devices, etc. The wireless terminal device can also be called a system, subscriber unit, subscriber station, mobile station, mobile, remote station, access point, remote terminal, access terminal, user terminal, user agent, user device, and wireless access points and routers / modems that meet the limitations of this definition, etc., which are not limited in the embodiments of the present application.

[0085] The network device involved in the embodiments of the present application may be a base station, which may include multiple cells that provide services to terminal devices. Depending on the specific application scenario, the base station may also be referred to as an access point, or may be a device in the access network that communicates with wireless terminal devices through one or more sectors over the air interface, or other names. The network device can be used to mutually replace the received air frames and Internet Protocol (IP) packets, and act as a router between the wireless terminal device and the rest of the access network, where the rest of the access network may include an IP communication network. The network device can also coordinate the management of the attributes of the air interface. For example, the network device involved in the embodiments of the present application may be an evolved network device (eNB or e-NodeB) in a Long Term Evolution (LTE) system, a 5G base station (gNB) in a 5G network architecture (next generation system), etc., or may also be a Home evolved Node B (HeNB), a relay node, a femto, a pico, a network test device, etc. The embodiments of the present application do not limit this. In some network architectures, the network device may include a centralized unit (CU) node and a distributed unit (DU) node, and the centralized unit and the distributed unit may also be geographically separated.

[0086] The network device and the terminal device can each use one or more antennas for multiple-input multiple-output (MIMO) transmission. The MIMO transmission can be single-user MIMO or multi-user MIMO. Depending on the form and quantity of the combined root antennas, the MIMO transmission can be 2D-MIMO, 3D-MIMO, FD-MIMO, or massive-MIMO, or can also be diversity transmission, precoding transmission, beamforming transmission, etc.

[0087] In the embodiments of the present application, when the terminal device sends relevant information or a similar description to the network device, it only indicates that the relevant information is sent in the form of a wireless signal, and the intended recipient is the network device. The network device can obtain the relevant information by receiving the wireless signal.

[0088] In an exemplary embodiment, as Figure 2 shown, a method for inter-stream interference cancellation is provided, and this method is described by taking its application to a base station as an example. As Figure 2 shown, the method for inter-stream interference cancellation may include:

[0089] Step S201: Obtain the LS channel estimation results of each subcarrier on the pilot.

[0090] The pilot is data known to both the terminal device and the base station. The pilot does not carry information. Inserting the pilot into the signal can perform channel estimation when receiving the signal. There can be multiple pilots. Here, a column of pilots is taken as an example to illustrate the inter-stream interference cancellation method provided by the embodiments of the present application, and other columns of pilots will not be elaborated.

[0091] The pilot can include multiple subcarriers. The base station can obtain the LS (Least Square Error) channel estimation results of each subcarrier. The LS channel estimation result of a subcarrier is the channel estimation result of the subcarrier obtained by using the least squares method. In one example, the channel estimation module of the base station can output the LS channel results of each subcarrier on the pilot. The channel estimation module can refer to the related technology and will not be elaborated here.

[0092] In a possible implementation manner, the product of the number of resource blocks (RBs) on the pilot and the number of subcarriers in each resource block can be determined as the number of subcarriers on the pilot.

[0093] Among them, the number of resource blocks on the pilot can be configured as needed. For example, it can be 8, 9, 10, 11, 12, 13, 14, 15, or 16, etc. The number of subcarriers in each resource block can be determined according to the configuration type. For example, the number of subcarriers in each resource block is 6 under configuration type 1, and the number of subcarriers in each resource block is 4 under configuration type 2, etc. For example, if the configuration type is 1, the number of subcarriers on the pilot is If the configuration type is 2, the number of subcarriers on the pilot is It should be noted that the number of resource blocks on the pilot and the number of subcarriers in each resource block are pre-configured. In the embodiments of the present application, neither the configuration method nor the configuration result is limited.

[0094] Step S202: Determine the phase offset estimation result according to the LS channel estimation results of each subcarrier.

[0095] After the base station obtains the LS channel estimation results of each subcarrier, it can determine the phase offset estimation result according to the LS channel estimation results of each subcarrier. This phase offset estimation result can characterize the phase offset situation of the channel.

[0096] In a possible implementation, step S202 may include: determining the k-th subcarrier and the (k + δ)-th subcarrier as a pair of sampled adjacent subcarriers; performing a conjugate multiplication operation on the LS channel estimation result of the k-th subcarrier and the LS channel estimation result of the (k + δ)-th subcarrier to obtain the conjugate multiplication result of the pair of sampled adjacent subcarriers; performing an accumulation operation and a normalization process on the conjugate multiplication results of each pair of sampled adjacent subcarriers to obtain the phase offset estimation result.

[0097] Wherein, δ may represent the offset between a pair of sampled adjacent subcarriers. δ can be set as needed, for example, it can be 1 or 2, etc. If L represents the number of subcarriers included in the pilot, that is, there are L subcarriers in the pilot, then 0 ≤ k ≤ L - δ - 1. L, k, and δ are integers. Taking L = 4 and δ = 1 as an example, the values of k are 0, 1, and 2. At this time, there are 4 subcarriers in the pilot, that is, the 0-th subcarrier to the 3-th subcarrier; three pairs of sampled adjacent subcarriers are determined, that is, a pair of sampled adjacent subcarriers composed of the 0-th subcarrier and the 1-th subcarrier, a pair of sampled adjacent subcarriers composed of the 1-th subcarrier and the 2-th subcarrier, and a pair of sampled adjacent subcarriers composed of the 2-th subcarrier and the 3-th subcarrier. Taking L = 4 and δ = 2 as an example, the values of k are 0 and 1. At this time, there are 4 subcarriers in the pilot, that is, the 0-th subcarrier to the 3-th subcarrier; two pairs of sampled adjacent subcarriers are determined, that is, a pair of sampled adjacent subcarriers composed of the 0-th subcarrier and the 2-th subcarrier, and a pair of sampled adjacent subcarriers composed of the 1-th subcarrier and the 3-th subcarrier.

[0098] After determining each pair of sampled adjacent subcarriers, the conjugate multiplication result of each pair of sampled adjacent subcarriers can be calculated. The conjugate multiplication result of a pair of sampled adjacent subcarriers can characterize the phase offset between the two subcarriers it includes. Therefore, by performing an accumulation operation and a normalization process on the conjugate multiplication results of each pair of sampled adjacent subcarriers, the phase offset estimation result of the pilot can be obtained.

[0099] In one example, the phase offset estimation result can be obtained using Equation 1.

[0100]

[0101] Wherein, represents the phase offset estimation result. H(k) represents the LS channel estimation result of the k-th subcarrier. H(k + δ) represents the channel estimation result of the (k + δ)-th subcarrier. H * (k + δ) represents the conjugate of the channel estimation result of the (k + δ)-th subcarrier. H(k)H * (k + δ) represents the conjugate multiplication result of the channel estimation results of the k-th subcarrier and the (k + δ)-th subcarrier.

[0102] Step S203: Determine the channel delay based on the phase deviation estimation result.

[0103] The phase offset that occurs in the subcarriers of the pilot can reflect the channel delay condition. Therefore, the base station can determine the channel delay based on the phase deviation estimation result.

[0104] In a possible implementation, step S203 may include: determining the channel delay according to the phase deviation estimation result and the preset number of sampling points.

[0105] Among them, the preset number of sampling points represents the number of sampling points of the Fast Fourier Transform (FFT) under the current bandwidth. It can be understood that the preset number of sampling points has an associated relationship with the bandwidth. In the case of a larger bandwidth, the preset number of sampling points can be larger; in the case of a smaller bandwidth, the preset number of sampling points can be smaller. In one example, the preset number of sampling points can be 2048 under a 20M bandwidth and a 30M bandwidth; in the case of a bandwidth greater than 30M, the preset number of sampling points can be set to a value of 4096; in the case of a bandwidth less than 20M, the preset number of sampling points can be set to a value of 1024. The embodiments of the present application do not limit the preset number of sampling points.

[0106] In one example, the step of determining the channel delay according to the phase deviation estimation result and the preset number of sampling points may include: determining the ratio of the imaginary part to the real part of the phase deviation estimation result; multiplying the preset number of sampling points by the arctangent operation result of this ratio to obtain a first product; determining the channel delay according to the ratio of the first product to the offset between a pair of adjacent sampled subcarriers. For example, the channel delay can be determined using formula two:

[0107]

[0108] Among them, irt represents the channel delay, represents the phase deviation estimation result, represents the imaginary part of the phase deviation estimation result, represents the real part of the phase deviation estimation result, N represents the preset number of sampling points, and δ represents the offset between a pair of adjacent sampled subcarriers.

[0109] Formula two is obtained based on formula one. The derivation process from formula one to formula two is as follows:

[0110]

[0111] Let irt = Δt, then

[0112] In one example, the steps of determining the channel delay according to the phase deviation estimation result and the preset number of sampling points may include: determining the phase angle according to the phase deviation estimation result; multiplying the preset number of sampling points by the phase angle to obtain a second product; determining the channel delay according to the ratio of the second product to the offset between a pair of adjacent sampled subcarriers. For example, the channel delay can be determined using Equation 3:

[0113]

[0114] where irt represents the channel delay, represents the phase angle, can be determined using Equation 4. N represents the preset number of sampling points, and δ represents the offset between a pair of adjacent sampled subcarriers. Among them, 15000, that is, 15KHz, can be expressed as 15K, that is, 15KHz. 15KHz is the subcarrier spacing adopted in the Frequency Division Duplexing (FDD) mode of the NR system.

[0115]

[0116] Among them, Equation 3 can be obtained based on Equation 2, and the derivation process from Equation 2 to Equation 3 is as follows:

[0117] Let Then Convert irt to the unit of 16T C where, Then

[0118] In the application process, _mm512_atan2_ps, that is, the arctangent function, can be used to implement Equation 4. _mm512_atan2_ps has two input parameters, namely and The output of _mm512_atan2_ps is the phase angle

[0119] In the embodiments of the present application, determining the channel delay based on the LS channel estimation result of the subcarrier is actually calculating the channel delay based on the PUSCH signal itself. Compared with calculating the channel delay using the SRS signal in the related art, the channel delay calculated in the embodiments of the present application has higher real-time performance and accuracy, and has stronger ability to resist the delay in the signal transmission process.

[0120] Step S204, based on the phase deviation estimation result, perform phase compensation on the LS channel estimation result of each subcarrier to obtain the compensated LS channel estimation result of each subcarrier.

[0121] In an embodiment of the present application, the base station may also perform phase compensation on the LS channel estimation result of the subcarrier based on the phase deviation estimation result, so as to perform inter-stream interference cancellation based on the LS channel estimation result after subcarrier compensation subsequently, and further improve the channel estimation performance.

[0122] In a possible implementation manner, step S204 may include: determining a phase angle according to the phase deviation estimation result; and performing phase compensation on the LS channel estimation result of each subcarrier by using the phase angle to obtain the LS channel estimation result after compensation for each subcarrier.

[0123] The base station may first use Equation 4 to determine the phase angle according to the phase deviation estimation result; and then perform phase compensation on the LS channel result of each subcarrier by using the phase angle.

[0124] In an example, the base station may construct an intermediate result with the cosine value of the phase angle as the real part and the sine value of the phase angle as the imaginary part, and multiply the LS channel estimation result of each subcarrier by the intermediate result to obtain the LS channel estimation result after compensation for each subcarrier. For example, the LS channel estimation result after compensation for each subcarrier may be obtained by using Equation 5:

[0125]

[0126] where H’(p) represents the LS channel estimation result after compensation for the p-th subcarrier, and H(p) represents the LS channel estimation result of the p-th subcarrier, represents the phase angle, 0 ≤ p ≤ L - 1, and p is an integer.

[0127] Step S205, perform inter-stream interference cancellation based on the LS channel estimation results after compensation for each subcarrier and the channel time delay.

[0128] The main function of inter-stream interference cancellation is to suppress the mutual interference generated by the received signals on two ports due to the channel time delay, so as to improve the receiving performance. The base station may subtract the phase generated by multiplying the channel estimation result on one subcarrier by the channel time delay from the channel estimation result on another subcarrier, so as to cancel the inter-stream interference.

[0129] The above inter-stream interference cancellation method determines the phase offset estimation result based on the minimum mean square error channel estimation results of each subcarrier on the pilot, and performs phase compensation on the minimum mean square error channel estimation results of each subcarrier according to the phase offset estimation result, and determines the channel delay according to the phase offset estimation result, so as to perform inter-stream interference cancellation according to the minimum mean square error channel results and the channel delay after compensation of each subcarrier. In this way, on the one hand, by determining the channel delay based on the phase offset estimation result, the accuracy of the channel delay is improved; on the other hand, by combining phase offset compensation and channel delay for inter-stream interference cancellation, the anti-interference effect against large delays in the signal transmission process is enhanced. Therefore, the performance of channel estimation is strongly enhanced, thereby improving the uplink signal demodulation performance.

[0130] Figure 3 Fig. shows a schematic structural diagram of an inter-stream interference cancellation system provided by an embodiment of the present application. This system can be set on a base station. As Figure 3 shown, the system may include: a channel estimation module, a phase offset estimation and compensation module, and an inter-stream interference cancellation module. Among them, the input port of the phase offset estimation and compensation module is connected to the output port of the channel estimation module, and the output port of the phase offset estimation and compensation module is connected to the input port of the inter-stream interference cancellation module.

[0131] The channel estimation module can output the LS estimation result on the r-th receiving antenna and the p-th port on the l-th column of pilots

[0132] The phase offset estimation and compensation module receives the LS estimation results on each port of each receiving antenna on each column of pilots, and determines the channel delay on each port and the LS channel estimation result after subcarrier compensation on each port. Among them, the method for determining the channel delay and compensating the LS channel estimation result can refer to the inter-stream interference cancellation method provided by the embodiment of the present application, which will not be elaborated here. In one example, irt (l，r，p) represents the channel delay on the r-th receiving antenna and the p-th port on the l-th column of pilots.

[0133] After receiving the channel delay of each port and the LS channel estimation result after subcarrier compensation of each port, the inter-stream interference cancellation module performs inter-stream interference cancellation, thereby improving the receiving performance.

[0134] It can be understood that the phase offset estimation and compensation module and the inter-stream interference cancellation module can be two independent modules, or can be integrated into one module. For example, the phase offset estimation and compensation module can be set in the inter-stream interference cancellation module, and the inter-stream interference cancellation module first determines the channel delay and the LS channel estimation result after subcarrier compensation, as well as inter-stream interference cancellation. In the embodiment of the present application, the setting manner of the phase offset estimation and compensation module and the inter-stream interference cancellation module is not limited.

[0135] The process of inter-stream interference cancellation requires two input parameters, one is the LS channel estimation result and the other is the channel time delay. In the embodiment of the present application, on the one hand, the LS channel estimation result after subcarrier compensation is used to replace the LS channel estimation result output by the channel estimation module; on the other hand, the channel time delay calculated using the phase deviation estimation result is used to replace the channel time delay calculated using SRS. In this way, the anti-interference effect against large time delays during signal transmission is improved. Therefore, the performance of channel estimation is strongly improved, thereby improving the uplink signal demodulation performance.

[0136] It should be understood that although the steps in the flowcharts involved in the above-described embodiments are sequentially shown according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise clearly stated in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least some of the steps in the flowcharts involved in the above-described embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least some of the steps or stages in other steps or other steps.

[0137] Based on the same inventive concept, the embodiment of the present application also provides an inter-stream interference cancellation device for implementing the above-mentioned inter-stream interference cancellation method. The solution provided by this device to solve the problem is similar to the solution described in the above method. Therefore, the specific limitations in one or more embodiments of the inter-stream interference cancellation device provided below can refer to the limitations on the inter-stream interference cancellation method in the above text, and will not be repeated here.

[0138] In an exemplary embodiment, Figure 4 shows a structural block diagram of the inter-stream interference cancellation device provided by the embodiment of the present application. As Figure 4 shown, the inter-stream interference cancellation device 400 may include: an acquisition unit 401, a first determination unit 402, a second determination unit 403, a compensation unit 404, and an elimination unit 405, where:

[0139] The acquisition unit is used to acquire the least square error (LS) channel estimation result of each subcarrier on the pilot;

[0140] The first determination unit is used to determine the phase deviation estimation result according to the LS channel estimation result of each subcarrier;

[0141] The second determination unit is used to determine the channel time delay based on the phase deviation estimation result;

[0142] A compensation unit, configured to perform phase compensation on the LS channel estimation results of each subcarrier based on the phase offset estimation result, so as to obtain the compensated LS channel estimation results of each subcarrier;

[0143] An interference cancellation unit, configured to perform inter-stream interference cancellation based on the compensated LS channel estimation results of each subcarrier and the channel delay.

[0144] In a possible implementation, the pilot includes L subcarriers, where L is a positive integer, and the first determination unit is further configured to:

[0145] Determine the k-th subcarrier and the (k + δ)-th subcarrier as a pair of sampled adjacent subcarriers, where 0 ≤ k ≤ L - δ - 1, k and δ are integers, and δ represents the offset between a pair of sampled adjacent subcarriers;

[0146] Perform a conjugate multiplication operation on the LS channel estimation result of the k-th subcarrier and the LS channel estimation result of the (k + δ)-th subcarrier to obtain the conjugate multiplication result of a pair of sampled adjacent subcarriers;

[0147] Perform an accumulation operation and a normalization process on the conjugate multiplication results of each pair of sampled adjacent subcarriers to obtain the phase offset estimation result.

[0148] In a possible implementation, the inter-stream interference cancellation device further includes:

[0149] A third determination unit, configured to determine the product of the number of resource blocks on the pilot and the number of subcarriers in each resource block as the number of subcarriers on the pilot.

[0150] In a possible implementation, the second determination unit is further configured to:

[0151] Determine the channel delay according to the phase offset estimation result and the preset number of sampling points.

[0152] In a possible implementation, determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes:

[0153] Determine the ratio of the imaginary part to the real part of the phase offset estimation result;

[0154] Multiply the preset number of sampling points by the arctangent operation result of the ratio to obtain a first product;

[0155] Determine the channel delay according to the ratio of the first product to the offset between a pair of sampled adjacent subcarriers.

[0156] In a possible implementation, determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes:

[0157] Determine the phase angle according to the phase offset estimation result;

[0158] Multiply the preset number of sampling points by the phase angle to obtain a second product;

[0159] Determine the channel delay according to the ratio of the second product to the offset between a pair of adjacent sampled subcarriers.

[0160] In a possible implementation manner, the compensation unit is further configured to:

[0161] Determine the phase angle according to the phase deviation estimation result;

[0162] Perform phase compensation on the LS channel estimation result of each subcarrier by using the phase angle to obtain the LS channel estimation result after compensation for each subcarrier.

[0163] In a possible implementation manner, performing phase compensation on the LS channel estimation result of each subcarrier by using the phase angle to obtain the LS channel estimation result after compensation for each subcarrier includes: constructing an intermediate result with the cosine value of the phase angle as the real part and the sine value of the phase angle as the imaginary part; multiplying the LS channel estimation result of each subcarrier by the intermediate result to obtain the LS channel estimation result after compensation for each subcarrier.

[0164] It should be noted that the division of units in the embodiments of the present application is illustrative, and is only a logical function division. In actual implementation, there may be other division methods. In addition, in each embodiment of the present application, each functional unit may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit. The above integrated units may be implemented in the form of hardware or in the form of software functional units.

[0165] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a processor-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, may be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the methods in the embodiments of the present application.

[0166] It should be noted here that the above device provided in the embodiments of the present invention can implement all the method steps implemented in the above method embodiments, and can achieve the same technical effects. The same parts and beneficial effects as those in the method embodiments will not be specifically described in this embodiment.

[0167] In an exemplary embodiment, a cross-stream interference cancellation device is provided. The cross-stream interference cancellation device may be a network device, and its internal structure may be as shown in Figure 5 The cross-stream interference cancellation device includes a memory 1120, a transceiver 1110, and a processor 1100.

[0168] The transceiver is configured to receive and send data under the control of the processor.

[0169] Among them, in Figure 5 , the bus architecture may include any number of interconnected buses and bridges, specifically various circuits of one or more processors represented by the processor and the memory represented by the memory are linked together. The bus architecture can also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art, and thus will not be further described herein. The bus interface provides an interface. The transceiver may be multiple elements, that is, including a transmitter and a receiver, and provides a unit for communicating with various other devices on a transmission medium, and these transmission mediums include wireless channels, wired channels, optical fiber cables, and other transmission mediums. The processor is responsible for managing the bus architecture and general processing, and the memory may store data used by the processor when executing operations.

[0170] The processor may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor may also adopt a multi-core architecture.

[0171] It should be noted here that the above device provided by the embodiments of the present invention can implement all the method steps implemented by the above method embodiments, and can achieve the same technical effects. The same parts and beneficial effects as those in the method embodiments will not be specifically described in this embodiment.

[0172] In an exemplary embodiment, a cross-stream interference cancellation device is provided, including a memory, a transceiver, and a processor:

[0173] The memory is configured to store a computer program; the transceiver is configured to receive and send data under the control of the processor; the processor is configured to read the computer program in the memory and perform the following operations:

[0174] Obtain the least squares error (LS) channel estimation results of each subcarrier on the pilot;

[0175] Determine the phase offset estimation result according to the LS channel estimation results of each subcarrier;

[0176] Determine the channel delay based on the phase offset estimation result;

[0177] Perform phase compensation on the LS channel estimation result of each subcarrier based on the phase offset estimation result to obtain the compensated LS channel estimation result of each subcarrier;

[0178] Perform interference cancellation between streams based on the compensated LS channel estimation results of each subcarrier and the channel delay.

[0179] In one embodiment, there are L subcarriers on the pilot, where L is a positive integer. When the processor executes the computer program, the following steps are also performed:

[0180] Determine the k-th subcarrier and the (k + δ)-th subcarrier as a pair of sampled adjacent subcarriers, where 0 ≤ k ≤ L - δ - 1, k and δ are integers, and δ represents the offset between a pair of sampled adjacent subcarriers;

[0181] Perform conjugate multiplication on the LS channel estimation result of the k-th subcarrier and the LS channel estimation result of the (k + δ)-th subcarrier to obtain the conjugate multiplication result of a pair of sampled adjacent subcarriers;

[0182] Perform accumulation operation and normalization processing on the conjugate multiplication results of each pair of sampled adjacent subcarriers to obtain the phase offset estimation result.

[0183] In one embodiment, when the processor executes the computer program, the following steps are also performed:

[0184] Determine the product of the number of resource blocks on the pilot and the number of subcarriers in each resource block as the number of subcarriers on the pilot.

[0185] In one embodiment, when the processor executes the computer program, the following steps are also performed:

[0186] Determine the channel delay according to the phase offset estimation result and the preset number of sampling points.

[0187] In one embodiment, when the processor executes the computer program, the following steps are also performed:

[0188] Determine the ratio of the imaginary part to the real part of the phase offset estimation result;

[0189] Multiply the preset number of sampling points by the arctangent operation result of the ratio to obtain the first product;

[0190] Determine the channel delay according to the ratio of the first product to the offset between a pair of sampled adjacent subcarriers.

[0191] In one embodiment, when the processor executes the computer program, the following steps are also performed:

[0192] Determine the phase angle according to the phase offset estimation result;

[0193] Multiply the preset number of sampling points by the phase angle to obtain a second product;

[0194] Determine the channel delay according to the ratio of the second product to the offset between a pair of adjacent sampled subcarriers.

[0195] In one embodiment, when the processor executes the computer program, the following steps are further performed:

[0196] Determine the phase angle according to the phase offset estimation result;

[0197] Perform phase compensation on the LS channel estimation result of each subcarrier by using the phase angle to obtain the LS channel estimation result after compensation for each subcarrier.

[0198] In one embodiment, when the processor executes the computer program, the following steps are further performed:

[0199] Construct an intermediate result with the cosine value of the phase angle as the real part and the sine value of the phase angle as the imaginary part;

[0200] Multiply the LS channel estimation result of each subcarrier by the intermediate result to obtain the LS channel estimation result after compensation for each subcarrier.

[0201] In an exemplary embodiment, a processor-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by the processor, the following steps are implemented:

[0202] Obtain the least squares (LS) channel estimation results of each subcarrier on the pilot;

[0203] Determine the phase offset estimation result according to the LS channel estimation results of each subcarrier;

[0204] Determine the channel delay based on the phase offset estimation result;

[0205] Perform phase compensation on the LS channel estimation result of each subcarrier based on the phase offset estimation result to obtain the LS channel estimation result after compensation for each subcarrier;

[0206] Perform inter-stream interference cancellation based on the LS channel estimation results after compensation for each subcarrier and the channel delay.

[0207] In one embodiment, the pilot includes L subcarriers, where L is a positive integer. When the computer program is executed by the processor, the following steps are further implemented:

[0208] Determine the k-th subcarrier and the (k + δ)-th subcarrier as a pair of sampled adjacent subcarriers, where 0 ≤ k ≤ L - δ - 1, k and δ are integers, and δ represents the offset between a pair of sampled adjacent subcarriers;

[0209] Perform a conjugate multiplication operation on the LS channel estimation result of the k-th subcarrier and the LS channel estimation result of the (k + δ)-th subcarrier to obtain the conjugate multiplication result of a pair of sampled adjacent subcarriers;

[0210] Perform an accumulation operation and a normalization process on the conjugate multiplication results of each pair of sampled adjacent subcarriers to obtain the phase offset estimation result.

[0211] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0212] Determine the product of the number of resource blocks on the pilot and the number of subcarriers in each resource block as the number of subcarriers on the pilot.

[0213] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0214] Determine the channel delay according to the phase offset estimation result and the preset number of sampling points.

[0215] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0216] Determine the ratio of the imaginary part to the real part of the phase offset estimation result;

[0217] Multiply the preset number of sampling points by the arctangent operation result of the ratio to obtain a first product;

[0218] Determine the channel delay according to the ratio of the first product to the offset between a pair of sampled adjacent subcarriers.

[0219] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0220] Determine the phase angle according to the phase offset estimation result;

[0221] Multiply the preset number of sampling points by the phase angle to obtain a second product;

[0222] Determine the channel delay according to the ratio of the second product to the offset between a pair of sampled adjacent subcarriers.

[0223] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0224] Determine the phase angle according to the phase offset estimation result;

[0225] Perform phase compensation on the LS channel estimation results of each subcarrier using the phase angle to obtain the LS channel estimation results after compensation for each subcarrier.

[0226] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0227] Construct an intermediate result with the cosine value of the phase angle as the real part and the sine value of the phase angle as the imaginary part;

[0228] Multiply the LS channel estimation result of each subcarrier by the intermediate result to obtain the LS channel estimation result after compensation for each subcarrier.

[0229] The processor-readable storage medium can be any available medium or data storage device accessible by the processor, including but not limited to magnetic memories (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO), etc.), optical memories (such as CDs, DVDs, BDs, HVDs, etc.), and semiconductor memories (such as ROM, EPROM, EEPROM, non-volatile memories (NAND FLASH), solid-state drives (SSD)).

[0230] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0231] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories and optical memories, etc.) containing computer-usable program code.

[0232] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as the combination of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0233] These computer-executable instructions may also be stored in a processor-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 a manufacture including instruction means embodying the function specified in the flowchart Figure 1 a flowchart or multiple flowcharts and / or blocks Figure 1 a block or multiple blocks.

[0234] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

Claims

1. A method for inter-stream interference cancellation, characterized in that, the method includes: obtaining the least squares (LS) channel estimation results of each subcarrier on the pilot; determining the phase offset estimation result according to the LS channel estimation results of each subcarrier; determining the channel delay based on the phase offset estimation result; performing phase compensation on the LS channel estimation result of each subcarrier based on the phase offset estimation result to obtain the compensated LS channel estimation result of each subcarrier; performing inter-stream interference cancellation based on the compensated LS channel estimation results of each subcarrier and the channel delay.

2. The method according to claim 1, characterized in that, there are L subcarriers on the pilot, L being a positive integer, and the step of determining the phase offset estimation result according to the LS channel estimation results of each subcarrier includes: determining the k-th subcarrier and the (k + δ)-th subcarrier as a pair of adjacent sampled subcarriers, where 0 ≤ k ≤ L - δ - 1, k and δ are integers, and δ represents the offset between a pair of adjacent sampled subcarriers; performing conjugate multiplication on the LS channel estimation result of the k-th subcarrier and the LS channel estimation result of the (k + δ)-th subcarrier to obtain the conjugate multiplication result of a pair of adjacent sampled subcarriers; performing accumulation and normalization processing on the conjugate multiplication results of each pair of adjacent sampled subcarriers to obtain the phase offset estimation result.

3. The method according to claim 1 or 2, characterized in that, the method further includes: determining the product of the number of resource blocks on the pilot and the number of subcarriers in each resource block as the number of subcarriers on the pilot.

4. The method according to claim 1, characterized in that, the step of determining the channel delay based on the phase offset estimation result includes: determining the channel delay according to the phase offset estimation result and the preset number of sampling points.

5. The method according to claim 4, characterized in that, the step of determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes: determining the ratio of the imaginary part to the real part of the phase offset estimation result; multiplying the preset number of sampling points by the arctangent operation result of the ratio to obtain a first product; determining the channel delay according to the ratio of the first product to the offset between a pair of adjacent sampled subcarriers.

6. The method according to claim 4, characterized in that, the step of determining the channel delay according to the phase offset estimation result and the preset number of sampling points includes: determining the phase angle according to the phase offset estimation result; multiplying the preset number of sampling points by the phase angle to obtain a second product; determining the channel delay according to the ratio of the second product to the offset between a pair of adjacent sampled subcarriers.

7. The method according to claim 1, characterized in that, the step of performing phase compensation on the LS channel estimation result of each subcarrier based on the phase offset estimation result to obtain the compensated LS channel estimation result of each subcarrier includes: determining the phase angle according to the phase offset estimation result; performing phase compensation on the LS channel estimation result of each subcarrier using the phase angle to obtain the compensated LS channel estimation result of each subcarrier.

8. The method according to claim 7, wherein, said using the phase angle to perform phase compensation on the LS channel estimation results of each subcarrier to obtain the LS channel estimation results after compensation for each subcarrier, includes: constructing an intermediate result with the cosine value of the phase angle as the real part and the sine value of the phase angle as the imaginary part; multiplying the LS channel estimation result of each subcarrier by the intermediate result to obtain the LS channel estimation result after compensation for each subcarrier.

9. An inter-stream interference cancellation device, wherein, it includes a memory, a transceiver, and a processor: The memory is used to store computer programs; the transceiver is used to transmit and receive data under the control of the processor; the processor is used to read the computer programs in the memory and perform the following operations: obtaining the least squares (LS) channel estimation results of each subcarrier on the pilot; determining a phase offset estimation result according to the LS channel estimation results of each subcarrier; determining a channel delay based on the phase offset estimation result; performing phase compensation on the LS channel estimation results of each subcarrier based on the phase offset estimation result to obtain the LS channel estimation results after compensation for each subcarrier; performing inter-stream interference cancellation based on the LS channel estimation results after compensation for each subcarrier and the channel delay.

10. An inter-stream interference cancellation device, wherein, it includes: an acquisition unit for obtaining the least squares (LS) channel estimation results of each subcarrier on the pilot; a first determination unit for determining a phase offset estimation result according to the LS channel estimation results of each subcarrier; a second determination unit for determining a channel delay based on the phase offset estimation result; a compensation unit for performing phase compensation on the LS channel estimation results of each subcarrier based on the phase offset estimation result to obtain the LS channel estimation results after compensation for each subcarrier; an elimination unit for performing inter-stream interference cancellation based on the LS channel estimation results after compensation for each subcarrier and the channel delay.

11. A processor-readable storage medium, wherein, the processor-readable storage medium stores a program, and the program is used to cause the processor to execute the method according to any one of claims 1 to 8.

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