CN113746576B

CN113746576B - Wireless channel recording method, device and medium based on 5G test signal

Info

Publication number: CN113746576B
Application number: CN202111292910.8A
Authority: CN
Inventors: 李丞
Original assignee: Beijing Jiaotong University
Current assignee: Beijing Jiaotong University
Priority date: 2021-11-03
Filing date: 2021-11-03
Publication date: 2022-07-19
Anticipated expiration: 2041-11-03
Also published as: CN113746576A

Abstract

The invention discloses a wireless channel recording method, a wireless channel recording device and a wireless channel recording medium based on a 5G test signal. The method comprises the following steps: setting the type and the test bandwidth of a test mode; generating a transmission block according to the type of the test mode and the test bandwidth; carrying out downlink shared channel processing and physical downlink shared channel processing on the transmission block to obtain a complex modulation signal; carrying out OFDM modulation on the complex modulation signal to generate a 5G test signal; and transmitting the 5G test signal. The invention uses the original base station to send the standard test mode signal, and the channel is closer to the channel experienced by the actual operation signal.

Description

Wireless channel recording method, device and medium based on 5G test signal

Technical Field

The invention relates to a wireless channel recording method based on a 5G test signal, and also relates to a base station and user equipment using the wireless channel recording method, belonging to the technical field of mobile communication.

Background

The principle of radio Channel recording is that a transmitter transmits a known training signal, a receiver stores a received signal, and estimates radio Channel information through the known transmitted signal to determine Channel Impulse Response (CIR) or Channel frequency domain Response. The transmitter and the receiver for channel measurement constitute a channel measurement system. Currently, the mainstream channel sounding signals mainly include continuous wave signals, narrow pulse signals, pseudo random signals, multi-carrier signals, and the like.

Through research, the inventor finds that the continuous wave signal is only suitable for static channel or narrow-band channel test; although the narrow pulse signal can be used for broadband channel testing, the peak average power is large, and the influence of device nonlinearity and noise is very large; the pseudo-random signal has a larger bandwidth and a lower peak-to-average power ratio, and is most widely applied to current channel detection, but the frequency domain of the pseudo-random signal is not flat enough, and the signal-to-noise ratios of different frequency components are different, so that the channel detection accuracy on different frequencies is inconsistent.

Disclosure of Invention

The invention aims to provide a wireless channel recording method based on a 5G test signal.

Another technical problem to be solved by the present invention is to provide a base station and a user equipment using the above wireless channel recording method.

Another object of the present invention is to provide a computer-readable storage medium for implementing the above wireless channel recording method.

In order to achieve the technical purpose, the invention adopts the following technical scheme:

according to a first aspect of the embodiments of the present invention, a method for recording a wireless channel based on a 5G test signal is provided, which is applied to a base station, and includes the following steps:

setting the type and the test bandwidth of a test mode signal;

generating a transmission block according to the type of the test mode signal and the test bandwidth;

performing downlink shared channel processing and physical downlink shared channel processing on the transmission block to obtain a complex modulation signal;

carrying out OFDM modulation on the complex modulation signal to generate a 5G test signal;

and transmitting the 5G test signal through a radio frequency port.

Preferably, the setting of the type and the test bandwidth of the test mode signal includes:

selecting a type of a test mode signal and determining a test bandwidth corresponding to the type of the selected test mode signal;

wherein the type of the test mode signal includes any one of: TM1.1, TM1.2, TM2, TM2a, TM3.1, TM3.1a, TM3.2, TM 3.3.

Preferably, the performing downlink shared channel processing and physical downlink shared channel processing on the transmission block to obtain a complex modulation signal specifically includes:

firstly, the downlink shared channel processing is carried out on the transmission block, and the processing comprises the following steps: sequentially performing CRC encoding, code block segmentation, LDPC encoding and rate matching on the transmission block to form a code word;

then, performing physical downlink shared channel processing to obtain a complex modulation signal, which specifically includes: and scrambling, symbol modulation and layer mapping are sequentially carried out on the code words to obtain complex modulation signals.

According to a second aspect of the embodiments of the present invention, there is provided a wireless channel recording method based on 5G test signals, which is applied to a user equipment, and includes the following steps:

OFDM demodulation in the full bandwidth is carried out on the received signal;

and performing channel estimation according to the test mode signal obtained after OFDM demodulation.

Preferably, the performing OFDM demodulation within the full bandwidth on the received signal specifically includes:

performing serial/parallel conversion on a received signal to decompose the received signal into a plurality of code streams lower than a preset rate threshold, wherein each code stream is transmitted by a subcarrier;

removing the cyclic prefix of each code stream;

performing fast Fourier transform on the code stream without the cyclic prefix, and recovering a modulated signal;

and performing parallel/serial conversion on the modulated signal and outputting the signal.

Preferably, the channel estimation according to the test mode signal obtained after OFDM demodulation specifically includes:

and determining channel impulse response according to the test mode signal.

Preferably, the determining the channel impulse response according to the test pattern signal further includes:

obtaining a power time delay spectrum according to the channel impulse response;

and performing peak detection on the power time delay spectrum according to a preset threshold value to obtain a small-scale fading parameter.

According to a third aspect of the embodiments of the present invention, there is provided a computer-readable storage medium, in which a computer program is stored, which, when executed by a processor, implements the above-mentioned wireless channel recording method based on a 5G test signal.

According to a fourth aspect of the embodiments of the present invention, there is provided a base station using the above-mentioned wireless channel recording method, including:

a transceiver;

a memory for storing one or more programs;

a processor communicatively coupled with the transceiver and the memory, the processor configured to execute the one or more programs to:

setting the type and test bandwidth of a test mode signal;

and sending the 5G test signal through a radio frequency port.

According to a fifth aspect of the embodiments of the present invention, there is provided a user equipment using the above-mentioned wireless channel recording method, including:

a transceiver;

a memory for storing one or more programs;

OFDM demodulation in the full bandwidth is carried out on the received signal;

In the prior art, a wireless channel recording needs to install a channel measurement transmitting device and an antenna by itself, but the position of a base station cannot be completely restored due to environmental limitation, so that the recorded channel is different from the channel experienced by an actual operation signal. The embodiment of the invention provides a wireless channel recording scheme based on a detection method, which uses a 5G-test mode signal as a channel detection signal to record a channel. Since the original base station is used to transmit the standard test mode signal, the channel measurement result has better consistency with the channel experienced when the actual network operates.

Drawings

FIG. 1 is a diagram illustrating the number of slots included in a subframe according to an embodiment of the present invention;

FIG. 2 illustrates the definition of resource units and resource blocks in NR according to an embodiment of the present invention;

fig. 3A is a functional block diagram of a wireless channel recording method based on a 5G test signal in an embodiment of the present invention;

FIG. 3B is a logic diagram of the transmission and reception of the test mode signal according to the embodiment of the present invention;

FIG. 4 is a flowchart of OFDM demodulation at the receiving end according to the embodiment of the present invention;

FIG. 5 is a flow chart of the multi-path parameter extraction method in the embodiment of the present invention;

fig. 6 is a functional block diagram of a wireless channel recording apparatus 300 based on 5G test signals according to an embodiment of the present invention;

fig. 7 is a functional block diagram of a wireless channel recording apparatus 400 based on a 5G test signal according to an embodiment of the present invention.

Detailed Description

The technical contents of the invention are described in detail below with reference to the accompanying drawings and specific embodiments.

The embodiment of the invention firstly provides an improved wireless channel recording method, and a 5G TM (Test Mode) signal is used as a channel detection signal to record a channel. The recording Reference Signal Received Power (RSRP), Signal-to-Interference-plus-Noise (SINR), multipath (relative Power, number of multipath, and multipath delay), and Multiple Input Multiple Output (MIMO) channel correlation coefficients.

In the 3GPP 5G NR standard, a set of signals for conformance testing is defined. The downlink consistency waveforms have two specific types, one is a New Radio interface (NR) test mode (NR-TM) for a Base Station (BS) Radio Frequency (Radio Frequency) test, and the other is a Fixed Reference Channel (FRC) for a User Equipment (User Equipment, UE) input test. The embodiment of the invention adopts the test mode signal to carry out channel detection.

The NR _ TM of FR1 is defined in TS 38.141-1, section 4.9.2, and the NR _ TM of FR2 is defined in TS 38.141-2, section 4.9.2. They can be used for a series of radio frequency tests, including: base station output power, timing offset (TAE), Adjacent Channel Leakage Ratio (ACLR). The test pattern signal has different Physical Downlink Shared Channel (PDSCH) characteristics according to the test pattern. For example: full band, single modulation scheme, or full band, multiple modulation schemes, different Physical Resource Block (PRB) allocations. Common features of all types of test pattern signals are: there is no Synchronization Signal Block (SSB) configuration, the mapping Type of the PDSCH is Type a, only one (FR 2, Frequency range 2) or two (FR 1, Frequency range 1) Demodulation Reference Signal (DM-RS) is transmitted per slot, and a Physical Downlink Control Channel (PDCCH) occupies two Orthogonal Frequency Division Multiplexing (OFDM) symbols. The NR-TM waveform length of Frequency Division Duplexing (FDD) is 10ms, and the Time Division Duplexing (TDD) waveform length is 20 ms.

In the 5G standard, resources in time and frequency are divided according to the following structure: the transmission of the NR standard consists of 10ms frames as seen in the time domain. Each frame is divided into 10 subframes of equal time length, each subframe being 1ms in duration. Each sub-frame is further divided into a number of slots, each slot consisting of 14 OFDM symbols. A slot is a basic unit of scheduling and consists of a fixed number of OFDM symbols. The length of each time slot is determined by the selected parameter set, as shown in table 1.

Table 1: time domain length corresponding to 5G NR different parameter sets

Fig. 1 shows the number of slots included in one subframe according to an embodiment of the present invention. As shown in fig. 1, the definition of frames, subframes, and slots in NR is shown.

Fig. 2 is a diagram illustrating the definition of resource units and resource blocks in NR according to an embodiment of the present invention. In the frequency domain, a Resource Element (RE) is defined as a subcarrier on one OFDM symbol and is also the smallest physical Resource in NR. The 12 consecutive subcarriers in the frequency domain are referred to as one resource block. As shown in fig. 2, in the NR standard, multiple parameter sets can be supported on one carrier, so that multiple resource grids are defined, and each resource grid corresponds to one parameter set. Although one resource block fixedly includes 12 subcarriers, actual bandwidths occupied by different parameter sets in the frequency domain are different due to different subcarrier spacing (SCS). The NR carriers configure a maximum of 275 resource blocks, i.e., 3300 subcarriers. The corresponding subcarrier spacing is 15/30/60/120kHz and the maximum carrier bandwidth is 50/100/200/400 MHz. Tables 2.1 and 2.2 show the relationship between the channel bandwidth and the number of Resource Blocks (RBs).

Table 2.1: channel bandwidth W and RB number (N)_RB) Corresponding relation 1

Table 2.2: channel bandwidth W and RB number (N)_RB) Corresponding relation two

< first embodiment >

Fig. 3A is a functional block diagram of a wireless channel recording method based on a 5G test signal in an embodiment of the present invention; fig. 3B is a logic diagram of transmitting and receiving a test mode signal according to an embodiment of the present invention. As shown in fig. 3A and 3B, the transmission and reception flow of the test mode signal includes:

the work flow of the transmitting terminal comprises the following steps:

s11, setting parameters such as the type and the test bandwidth of the test mode signal;

the generated transport block size, data fill position are related to the type of test pattern signal and test bandwidth. Types of test mode signals are defined in 3GPP 38.141 for a total of 8 types, including TM1.1, TM1.2, TM2, TM2a, TM3.1, TM3.1a, TM3.2, TM 3.3. In different test mode signals, the physical resource block PRB positions of the PDSCH are different. For example, TM1.1, whose parameter configuration table is shown in table 3:

table 3: parameter configuration table of TM1.1 signal

S12, according to the transmission flow, generating transmission block bit data with corresponding size according to the configured test bandwidth, and according to the type of the configured test mode signal, searching the initial RB position and the initial OFDM symbol position occupied by the PDSCH in the parameter configuration table (table 3) of the selected test mode signal to perform data padding.

Data padding is to put the bit data of the transport block on the corresponding OFDM symbol position.

Step S12, obtaining a transmission block, and taking the configuration of 10MHz bandwidth, the subcarrier spacing being 15KHz, and the TM1.1 mode as an example, generating the transmission block includes:

1) the number of REs in each subframe is determined.

Wherein the content of the first and second substances,

is the number of subcarriers in each RB;

is the number of symbols allocated to PDSCH per subframe, and as can be seen from table 3, the initial OFDM symbol position occupied by PDSCH is 0, i.e., the number of symbols is

。

Wherein min () represents taking the minimum value,

is the total number of PRBs occupied by PDSCH, as can be seen from table 3, in TM1.1 mode,

(available from Table 2.1).

2) By passing

Obtaining information bit intermediate numbers

。

Wherein the content of the first and second substances,

in order to obtain the number of REs per subframe obtained in step 1, R is a code rate, R is 0.4785, Qm is a modulation order, and TM1.1 mode modulation scheme is QPSK, Qm is 2.

If it is used

Calculating the size of the transmission block through the step 3; if it is not

The transport block size is calculated by step 4.

3) When in use

The transport block size calculation steps are as follows.

Information bit quantized intermediate number

：

Wherein the content of the first and second substances,

looking up table 4, find a close but not less than

TBS (transport block size).

Table 4 transport block size

4) When in use

The transport block size calculation steps are as follows.

Information bit quantized intermediate number

：

Wherein the content of the first and second substances,

round means rounding down.

Transport block size TBS:

according to the obtained TBS, corresponding '0' and '1' bit data are generated, and data padding is performed according to the initial RB position and the initial OFDM symbol position occupied by the PDSCH in the table 3.

S13, performs DLSCH (Downlink Shared Channel) processing and PDSCH (Physical Downlink Shared Channel) processing on the transport block. The DLSCH channel processing includes CRC (Cyclic Redundancy Check) coding, Code block segmentation, LDPC (Low Density Parity Check Code) coding, and rate matching. The number of data segments and CRC additions depends on the size of the transport block. And each transmission block forms a code word after being respectively subjected to LDPC coding and rate matching. The code words are processed by a physical downlink shared channel, including scrambling, symbol modulation and layer mapping to form complex modulation signals.

CRC encoding: CRC, a cyclic redundancy check code, is a commonly used error detection check code for checking whether an error occurs during data transmission. The basic idea is to add a check code after the data frame to be transmitted, to generate a new frame and transmit it to the receiving end. The additional check code enables the new frame to be generated that is divisible by a certain number (modulo-2 division) selected jointly by the transmitting and receiving ends.

Code block segmentation: code block segmentation may ensure that the length of a code block entering an LDPC encoder is not greater than the size of the largest code block. Segmenting the input block into a plurality of smaller code blocks if the input block length is greater than the maximum code block; if the input block length is less than or equal to the maximum code block, segmentation is not required.

LDPC coding: the LDPC code is a linear block error correction code with sparse property of the check matrix first proposed by Gallager in 1962. The LDPC code has excellent performance approaching to Shannon capacity limit, relatively low decoding complexity and flexible construction, and is widely applied to systems such as 5G and the like.

Rate matching: rate matching means that bits on a transport channel are repeated or punctured to match the carrying capacity of the physical channel to achieve the bit rate required by the transport format. The puncturing means that the current bit is deleted and the following bits are sequentially moved forward by one bit; repetition is the insertion of the current bit once between the current bit and the next bit.

Scrambling: the encoded data may have continuous "0" or continuous "1", which breaks the balance between the "0" code and the "1" code and affects the establishment of synchronization. Scrambling avoids the occurrence of successive "0" or "1" by scrambling the encoded data with a pseudorandom sequence.

And (3) symbol modulation: the bits in the codeword are mapped to complex modulation symbols.

Layer mapping: the method is used for solving the problem that the code word is not matched with the number of the antennas.

Since the number of codewords is not consistent with the number of transmit antennas, the stream of codewords needs to be mapped to different transmit antennas, and thus layer mapping is used to map the complex modulation symbols in the codewords to one or more layers (see table 5). Wherein

Is the firstqThe complex modulation symbols of a single code word,

is as followsqThe number of complex modulation symbols of a single codeword,

is a symbol mapped onto a layer or layers,vis the number of layers,

is the number of symbols per layer.

Table 5 layer mapping correspondence table

S14, OFDM-modulates the generated complex modulation signal to generate a 5G test signal.

And S15, sending the 5G test signal through the hardware radio frequency port.

The working process of the receiving end comprises the following steps:

and S21, OFDM demodulation in the full bandwidth is carried out on the received signal.

Fig. 4 is a flowchart of OFDM demodulation at the receiving end according to the embodiment of the present invention. As shown in fig. 4, the OFDM demodulation process includes the following steps:

s211, performing serial/parallel conversion:

in the OFDM system, a high-speed data stream of a user is decomposed into a plurality of low-rate code streams after serial/parallel conversion, and each code stream can be transmitted by one subcarrier. This greatly increases the transmission period of each code element, which is far greater than the delay spread caused by multipath effect, reduces the inter-symbol interference, and simplifies the channel equalization operation of the receiving end.

S212, removing the cyclic prefix of the OFDM symbol:

cyclic Prefix (CP) refers to a symbol Prefix, which is repeated at the end of the OFDM symbol, and the receiving end is usually configured to discard the Cyclic Prefix. The CP may be used to block multipath delay spread.

S213, performing fast Fourier transform on the OFDM symbols:

strict mutual orthogonality between subcarriers is required in the OFDM system. Theoretically, it has been proved that the receiving end can better realize the orthogonal transformation by using the Fast Fourier Transform (FFT) technique.

At the transmitting end, an IFFT (Inverse Fast Fourier Transform) module may be used to map and superimpose the multiple subcarriers, and after IFFT, the frequency domain signal is converted into a time domain signal.

S214, performing parallel/serial conversion:

at the receiving end, the modulated signal is recovered by FFT conversion and then output by P/S conversion, i.e., parallel/serial conversion.

And S22, performing channel estimation by using the test mode signal.

According to the transmitted known 5G test signal and the received signal, the channel impulse response is calculated, and the power delay spectrum (PDP), Doppler spread and other related wireless channel parameters of the channel can be obtained through the channel impulse response.

In a wireless communication system, the performance of the system is mainly limited by the wireless channel. The propagation path between the base station and the receiver is complex and variable, and the propagation path is from simple line-of-sight transmission to propagation influenced by reflection, refraction and scattering of obstacles. In a wireless transmission environment, a received signal has multipath delay, time-selective fading and frequency domain offset, so that a channel needs to be estimated and further compensated. The quality of the signal estimation performance directly affects the demodulation result of the received signal.

The embodiment of the invention utilizes the test mode signal to carry out channel estimation and calculate the channel impulse response. The power delay spectrum is obtained by channel impulse response. After the power delay spectrum is obtained, peak detection can be carried out to obtain small-scale fading parameters including multipath distribution, time delay, power and Doppler frequency shift. As shown in fig. 5, the method comprises the following steps:

taking SISO system as an example, let the transmitted frequency domain test pattern signal be

The frequency domain test pattern signal after OFDM demodulation is

Then the channel frequency domain transfer function is

：

（1）

To reduce the side lobe of time domain, improve the resolution of multipath time delay and obtain complete multipath condition as far as possible, the transmission function of channel frequency domain

And carrying out windowing treatment. The Hanning window is a low complexity and fast sidelobe dropping window function. The channel frequency domain transfer function after adding the Hanning window is as follows:

（2）

wherein the content of the first and second substances,

，nthe length of the Hanning window.

Will be provided with

The channel impulse response can be obtained by fast Inverse Fourier transform (IFFT)

：

（3）

The power delay profile of the channel is:

（4）

will be provided with

Obtaining the Doppler spectrum through autocorrelation operation:

（5）

the discrete multipath information distribution condition can be obtained by carrying out peak value detection on the power time delay spectrum. In order to ensure the accuracy of the extracted multipath information, a power time delay spectrum threshold is set during peak detection, and the multipath with the peak power above the threshold is extracted as an effective path. And obtaining the time delay and the Doppler frequency shift corresponding to the position of the path according to the peak power position of the multipath, thus obtaining the small-scale fading characteristic parameters of the path.

The following describes the wireless channel recording method provided by the present invention with reference to an actual application scenario:

in this practical application scenario, wireless channel recording is performed in a high-speed railway environment.

The base station transmitter is configured in a test mode to continuously transmit a test mode signal.

The receiver is placed on a high-speed train, the transmitter and the receiver need to ensure synchronization and consistent speed, a received signal from a radio frequency front end can be converted into a digital baseband signal through a mixer, a low-pass filter, an analog-to-digital converter (ADC) and a digital down converter in sequence, and then the digital baseband signal is processed.

The method comprises the steps of carrying out synchronization and OFDM demodulation on transmission information received by a receiving end, mapping a transmission block to a baseband, then calculating channel impulse response on the received signal, obtaining related wireless channel parameters such as power delay spectrum, Doppler frequency shift and the like of a channel through the channel impulse response, and analyzing channel characteristics such as path loss, shadow fading and the like under the condition of known transmitting power.

The advantages of the above technical scheme include:

1. in the standard 5G signal, only a demodulation reference signal (DMRS) occupying a small part of a resource grid is used as a training sequence for channel estimation, other signal resources are wasted, and the measurement precision is limited. In the embodiment of the invention, the test mode signals are distributed in the full frequency band, the interval of one subcarrier at intervals is 15kHz in the frequency domain, the maximum measurable multipath time delay is 1/15kHz and is approximately equal to 66.6 mu s, and the measurement range of the multipath time delay is expanded. In addition, the test mode signal distributed in the full frequency band has more data to calculate the channel impulse response, so that more details can be seen, and the channel characteristics can be described more accurately.

2. The Test Mode (TM) signal is a standard signal for the radio frequency conformance test of the base station, and is defined differently for different radio frequency indicators, such as the base station transmit power, frequency Error, phase Error, EVM (Error Vector Magnitude), and the like. The standard test mode signal is used for channel recording, and performance verification and comparison are easy to perform.

3. The traditional wireless channel recording needs to install a channel measuring and transmitting device and an antenna by itself, but the position of a base station in an actual network cannot be completely restored due to the limitation of installation conditions, so that the recorded channel is different from the channel experienced by an actual operation signal. The embodiment of the invention uses the original base station to send the standard test mode signal, and the channel is closer to the actually operated channel.

4. The traditional wireless channel recording needs to build and install channel recording transmitting equipment (including an antenna feeder), the equipment is complex and high in cost, potential safety hazards exist, the implementation difficulty is high, and particularly in special scenes such as a high-speed railway and the like, the approval of an operation department is difficult to obtain. The embodiment of the invention records the channel by using the deployed 5G operation network, does not need to build and install channel measurement transmitting equipment (including an antenna feeder), has lower cost, does not need to change the original base station equipment, only needs to coordinate with a network operation unit, configures the 5G base station in the test area into a TM mode, and obviously reduces the overall implementation difficulty.

< second embodiment >

As shown in fig. 6, the present embodiment provides a wireless channel recording apparatus 300 based on 5G test signals, where the apparatus 300 is disposed on a base station, and includes:

a setting module 310, configured to set a type and a test bandwidth of the test mode signal;

a transmission block generating module 320, configured to generate a transmission block according to the type of the test mode signal and the test bandwidth;

a transmission block processing module 330, configured to perform downlink shared channel processing and physical downlink shared channel processing on the transmission block to obtain a complex modulation signal;

an OFDM modulation module 340, configured to perform OFDM modulation on the complex modulation signal to generate a 5G test signal;

a sending module 350, configured to send the 5G test signal through a radio frequency port.

< third embodiment >

As shown in fig. 7, the present embodiment provides a wireless channel recording apparatus 400 based on a 5G test signal, where the apparatus 400 is disposed on a user equipment, and includes:

an OFDM demodulation module 410, configured to perform OFDM demodulation within a full bandwidth on a received signal;

and a channel estimation module 420, configured to perform channel estimation according to the test mode signal obtained after OFDM demodulation.

< fourth embodiment >

The present embodiment provides a computer-readable storage medium in which a computer program is stored, which when executed by a processor implements any one of the wireless channel recording methods based on a 5G test signal of the first embodiment.

< fifth embodiment >

The present embodiment provides a base station, including:

a transceiver;

a memory for storing one or more programs;

setting the type and the test bandwidth of a test mode signal;

and transmitting the 5G test signal through a radio frequency port.

In one possible design, during the processing of the processor, the setting of the type of the test mode and the test bandwidth includes:

selecting a type of a test mode signal and determining a test bandwidth corresponding to the type of the selected test mode signal; wherein the type of the test mode signal includes any one of: TM1.1, TM1.2, TM2, TM2a, TM3.1, TM3.1a, TM3.2, TM 3.3.

In a possible design, in a processing process of the processor, the performing downlink shared channel processing and physical downlink shared channel processing on the transmission block to obtain a complex modulation signal specifically includes:

firstly, the downlink shared channel processing is carried out on the transmission block, and the method comprises the following steps: sequentially performing CRC encoding, code block segmentation, LDPC encoding and rate matching on the transmission block to form a code word;

< sixth embodiment >

The present embodiment provides a user equipment, including:

a transceiver;

a memory for storing one or more programs;

OFDM demodulation in the full bandwidth is carried out on the received signal;

In a possible design, in the processing process of the processor, the performing OFDM demodulation within the full bandwidth on the received signal specifically includes:

performing serial/parallel conversion on a received signal to decompose the received signal into a plurality of code streams lower than a preset rate threshold, each code stream being transmitted by one subcarrier;

removing the cyclic prefix of each code stream;

In a possible design, in the processing process of the processor, performing channel estimation according to a test mode signal obtained after OFDM demodulation specifically includes:

and determining channel impulse response according to the test mode signal.

In one possible design, the determining, during processing by the processor, a channel impulse response from the test pattern signal further includes:

The user equipment may further comprise a communication bus, a transceiver, a memory and a processor, wherein communication with each other is accomplished via the communication bus. The communication bus may be a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The communication bus may be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, only one thick line is shown, but this does not mean that there is only one bus or one type of bus. The communication interface is used for communication between the electronic equipment and other equipment.

The bus includes hardware, software, or both to couple the above components to each other. For example, a bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an infiniband interconnect, a Low Pin Count (LPC) bus, a memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a video electronics standards association local (VLB) bus, or other suitable bus or a combination of two or more of these. A bus may include one or more buses, where appropriate. Although specific buses have been described and shown in the embodiments of the invention, any suitable buses or interconnects are contemplated by the invention.

The Memory may include a Random Access Memory (RAM) or a Non-Volatile Memory (NVM), such as at least one disk Memory. Optionally, the memory may also be at least one memory device located remotely from the processor.

The memory may include mass storage for data or instructions. By way of example, and not limitation, memory may include a Hard Disk Drive (HDD), floppy Disk Drive, flash memory, optical Disk, magneto-optical Disk, magnetic tape, or Universal Serial Bus (USB) Drive or a combination of two or more of these. Memory may include removable or non-removable (or fixed) media, where appropriate. In a particular embodiment, the memory is non-volatile solid-state memory. In a particular embodiment, the memory includes Read Only Memory (ROM). Where appropriate, the ROM may be mask-programmed ROM, Programmable ROM (PROM), Erasable PROM (EPROM), Electrically Erasable PROM (EEPROM), electrically rewritable ROM (EAROM), or flash memory or a combination of two or more of these.

The processor may be a general-purpose processor including a Central Processing Unit (CPU), a Network Processor (NP), etc.; but may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, etc.

The wireless channel recording method, apparatus and medium based on 5G test signal provided by the present invention have been described in detail. It will be apparent to those skilled in the art that any obvious modifications thereof can be made without departing from the spirit of the invention, which infringes the patent right of the invention and bears the corresponding legal responsibility.

Claims

1. A wireless channel recording method based on 5G test signals is applied to user equipment and is characterized by comprising the following steps:

OFDM demodulation in the full bandwidth is carried out on received signals, the received signals are transmission block bit data with corresponding size generated by a base station according to configured test bandwidth, initial RB positions and initial OFDM symbol positions occupied by PDSCH in a parameter configuration table of selected test mode signals are searched for carrying out data filling, the bit data of the transmission blocks are placed on the corresponding OFDM symbol positions, and then LDPC coding and rate matching are carried out on each transmission block to form a code word; then, PDSCH processing is carried out on the code words to form complex modulation signals, and finally, signals obtained by carrying out OFDM modulation on the complex modulation signals are sent through a radio frequency port and then received;

2. the method for wireless channel recording according to claim 1, wherein the performing OFDM demodulation within the full bandwidth on the received signal specifically comprises:

performing serial/parallel conversion on a received signal to decompose the received signal into a plurality of code streams lower than a preset rate threshold, each code stream being transmitted by one subcarrier; removing the cyclic prefix of each code stream; performing fast Fourier transform on the code stream without the cyclic prefix, and recovering a modulated signal; and performing parallel/serial conversion on the modulated signal and outputting the signal.

3. The wireless channel recording method of claim 2, wherein determining a channel impulse response based on the test pattern signal, further comprises:

4. A computer-readable storage medium, in which a computer program is stored, which, when being executed by a processor, carries out a method for wireless channel recording based on a 5G test signal according to any one of claims 1 to 3.

5. A user equipment, comprising:

a transceiver;

a memory for storing one or more programs;

a processor communicatively coupled with the transceiver and the memory, the processor configured to execute the one or more programs to implement the method of 5G test signal based wireless channel recording of any of claims 1-3.