CN112821995B

CN112821995B - Feedback method of channel state information, base station and terminal

Info

Publication number: CN112821995B
Application number: CN201911120242.3A
Authority: CN
Inventors: 朱昀; 刘琦
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2019-11-15
Filing date: 2019-11-15
Publication date: 2022-05-10
Anticipated expiration: 2039-11-15
Also published as: CN112821995A

Abstract

The embodiment of the invention provides a feedback method of channel state information, a base station and a terminal, wherein the method comprises the following steps: sending a demodulation reference signal (DMRS) to a terminal on the bandwidth of a Physical Downlink Shared Channel (PDSCH), wherein the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH, so that the terminal can acquire channel state information on the bandwidth of the whole PDSCH according to the received DMRS; and receiving the channel state information fed back by the terminal. The embodiment of the invention improves the accuracy of the channel state information.

Description

Feedback method of channel state information, base station and terminal

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method, a base station, and a terminal for feeding back channel state information.

Background

In the prior art, physical Channel State feedback is implemented by a Channel State Information Reference signal (CSI-RS). The specific implementation process is that firstly, a base station configures CSI-RS pilot frequency resources to terminals, at this time, because CSI-RS is pilot frequency of a cell level, N sets of the CSI-RS pilot frequency resources are assumed to be configured in one cell, the base station configures one or more sets of the CSI-RS resources to each terminal, and one set of the CSI-RS resources comprises the sending period of the CSI-RS, the positions of time-frequency domain resources and sending power information; then, the terminal receives the CSI-RS signals in each CSI-RS period, calculates channel estimation according to a certain algorithm, and further calculates channel state information including a debugging mode, a coding rate, a precoding codebook and the number of data streams; then, the terminal feeds back the result after the calculation to the base station, and then the base station sends a Physical Downlink Shared Channel (PDSCH), that is, service data, to the terminal according to the fed back Channel state information.

However, the CSI-RS is sent at a certain period, and the terminal needs to receive the CSI-RS at multiple periods for a long time to calculate and obtain stable and accurate channel state information; in addition, since the CSI-RS is configured at the cell level, and the bandwidth of the CSI-RS is not consistent with the PDSCH bandwidth of the terminal, for the feedback of one terminal, the CSI-RS bandwidth is either wasted or cannot be covered, which results in inaccurate calculation.

For 5G high-reliability Low Latency Communications (URLLC) service, an extremely Low data error rate and an extremely short transmission Latency are required, and generally, the packet size of the URLLC service is 32Bytes, and the packet error rate is required to be less than 10^-5The end-to-end interaction delay requirement is less than 1ms, which requires that the channel state feedback can follow the channel variations very quickly and the computation is very accurate. At this time, if the terminal feeds back the channel state information in the above manner, the physical channel state feedback is too slow, and the channel state feedback is inaccurate and cannot be fullThe method is sufficient for the requirement of channel state feedback of 5G URLLC service.

Disclosure of Invention

The embodiment of the invention provides a feedback method of channel state information, a base station and a terminal, which are used for improving the feedback accuracy of a physical channel state.

The embodiment of the invention provides a feedback method of channel state information, which is applied to a base station and comprises the following steps:

sending a demodulation reference signal (DMRS) to a terminal on the bandwidth of a Physical Downlink Shared Channel (PDSCH), wherein the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH, so that the terminal can acquire channel state information on the bandwidth of the whole PDSCH according to the received DMRS;

and receiving the channel state information fed back by the terminal.

The embodiment of the invention provides a feedback method of channel state information, which is applied to a terminal and comprises the following steps:

receiving a demodulation reference signal DMRS (demodulation reference signal) sent by a base station on the bandwidth of a Physical Downlink Shared Channel (PDSCH), wherein the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH;

acquiring channel state information on the whole PDSCH bandwidth according to the received DMRS;

and feeding back the channel state information to a base station.

The embodiment of the invention provides a feedback device of channel state information, which is applied to a base station and comprises the following components:

the terminal comprises a sending module and a receiving module, wherein the sending module is used for sending a demodulation reference signal (DMRS) to the terminal on the bandwidth of a Physical Downlink Shared Channel (PDSCH), and the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH so that the terminal can acquire channel state information on the whole PDSCH bandwidth according to the received DMRS;

and the receiving module is used for receiving the channel state information fed back by the terminal.

The embodiment of the invention provides a feedback device of channel state information, which is applied to a terminal and comprises the following components:

the base station comprises a receiving module and a transmitting module, wherein the receiving module is used for receiving a demodulation reference signal DMRS (demodulation reference signal) sent by the base station on the bandwidth of a Physical Downlink Shared Channel (PDSCH), and the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH;

the acquisition module is used for acquiring channel state information on the whole PDSCH bandwidth according to the received DMRS;

and the sending module is used for feeding back the channel state information to the base station.

An embodiment of the present invention provides a base station, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor implements steps of a method applied to the base station when executing the program.

An embodiment of the present invention provides a terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor implements steps of a method applied to the terminal when executing the program.

Embodiments of the present invention provide a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, performs the steps of the method described.

According to the feedback method of the channel state information, the base station and the terminal provided by the embodiment of the invention, the DMRS is sent to the terminal on the PDSCH bandwidth, the DMRS bandwidth is greater than or equal to the PDSCH bandwidth, and the channel state information on the whole PDSCH bandwidth acquired based on the DMRS is received and fed back by the terminal, so that the channel state calculation and feedback are realized by replacing CSIRS through the DMRS, and the channel state information on the whole PDSCH bandwidth can be acquired by the terminal on the basis that the DMRS bandwidth is greater than or equal to the PDSCH bandwidth, so that the terminal can more accurately feed back the channel state on the scheduling bandwidth, and the feedback accuracy of the physical channel state is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

Fig. 1 is a flowchart illustrating steps of a method for feeding back channel state information applied to a base station according to an embodiment of the present invention;

fig. 2 is a schematic diagram of transmitting DMRS at the same OFDM symbol position in each PDSCH repetition block in an embodiment of the present invention;

fig. 3 is a schematic diagram illustrating that DMRS is transmitted in a concentrated manner at OFDM symbol positions at the front end of all PDSCH repeating blocks in an embodiment of the present invention;

fig. 4 is a flowchart illustrating steps of a method for feeding back channel state information applied to a terminal according to an embodiment of the present invention;

fig. 5 is a schematic interaction diagram of a base station and a terminal in the embodiment of the present invention;

fig. 6 is a block diagram of a feedback apparatus for channel state information applied to a base station according to an embodiment of the present invention;

fig. 7 is a block diagram of a feedback apparatus for channel state information applied to a terminal in an embodiment of the present invention;

FIG. 8 is a diagram illustrating a base station according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a terminal in an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1, which is a flowchart illustrating steps of a feedback method applied to channel state information of a channel in an embodiment of the present invention, the method includes the following steps:

step 101, sending a demodulation reference signal DMRS to a terminal on a PDSCH bandwidth.

In this step, specifically, when feeding back the channel state information, the base station may send a Demodulation Reference Signal (DMRS) to the terminal over the PDSCH bandwidth, where the DMRS bandwidth is greater than or equal to the PDSCH bandwidth, so that the terminal can obtain the channel state information over the entire PDSCH bandwidth according to the received DMRS.

At this time, the DMRS is used for replacing CSIRS to calculate and feed back the channel state, and based on that the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH, the terminal can acquire the channel state information on the whole PDSCH bandwidth, so that the terminal can feed back the channel state on the scheduling bandwidth more accurately, the feedback accuracy of the physical channel state is improved, and the channel state feedback requirement of the URLLC service is met.

Of course, preferably, the DMRS bandwidth is equal to the PDSCH bandwidth, which enables the terminal to obtain the channel state information on the entire PDSCH bandwidth without wasting other bandwidths when performing channel estimation based on the DMRS.

In addition, the pilot density based on the DMRS is higher than that of the CSIRS, so that the time for obtaining the channel state information by the terminal is shorter, that is, the time delay required for calculating the channel state information is shortened, and the feedback speed of the channel state information is improved.

And 102, receiving the channel state information fed back by the terminal.

In this step, specifically, after the terminal acquires the state information on the entire PDSCH bandwidth according to the received DMRS, the acquired channel state information is fed back to the base station, and at this time, the base station receives the channel state information fed back by the terminal, so that the base station can better send downlink data to the terminal according to the channel state information.

In addition, specifically, it should be noted herein that before the base station transmits the DMRS to the terminal on the PDSCH bandwidth, the base station may further transmit semi-static configuration information to the terminal through a Radio Resource Control (RRC) message, where the semi-static configuration information includes the DMRS configured to the terminal and a bandwidth configuration relationship that the DMRS bandwidth is greater than or equal to the PDSCH bandwidth.

Specifically, the base station sends semi-static configuration information to the terminal through an RRC message, and the semi-static configuration information includes a DMRS configured by the base station to the terminal and a bandwidth configuration relationship that a DMRS bandwidth is greater than or equal to a PDSCH bandwidth, so that the bandwidth configuration relationship can have a longer effective time.

In addition, it should be noted that, before the base station sends the DMRS to the terminal on the PDSCH bandwidth, when the URLLC Downlink service needs to be scheduled, the base station may send scheduling Information to the terminal through Downlink Control Information (DCI), where the scheduling Information includes the bandwidth Information of the PDSCH, so that the terminal can perform Downlink resource scheduling according to the scheduling Information.

Specifically, the bandwidth information of the PDSCH may include channel bandwidth and resource location of the PDSCH, and configuration information such as modulation level, code rate, and beamforming of the initial PDSCH.

In addition, further, when the base station transmits the DMRS to the terminal on the PDSCH bandwidth, the transmission scheme may include any one of the following two schemes:

firstly, a PDSCH repetition block and a DMRS are transmitted to a terminal through the same beamforming on a PDSCH bandwidth.

Specifically, in this scheme, the base station transmits the PDSCH repetition block and the DMRS to the terminal through the same beamforming.

For example, the base station may transmit the PDSCH repeating block and the DMRS to the terminal through the same set of beams, thereby facilitating the terminal to receive the PDSCH repeating block and the DMRS.

And secondly, transmitting a beam forming factor corresponding to a bandwidth binding block (bundle) to the terminal, and transmitting the PDSCH repetition block and the DMRS to the terminal by using different beam forming modes with the bundle as a unit.

Specifically, in this way, the base station may set a bundle for the PDSCH bandwidth, and each bundle adopts a different beamforming manner, and then the terminal may send the PDSCH repetition block and the DMRS to the terminal in units of bundles; in addition, the beamforming factor corresponding to each bundle needs to be sent to the terminal, so that the terminal can receive the PDSCH repetition block and the DMRS according to the beamforming factor corresponding to each bundle.

For example, assuming that the PDSCH bandwidth is 10M, a 2M bandwidth is one bundle, and each bundle adopts a different beamforming manner, at this time, the base station may send a beamforming factor corresponding to each bundle to the terminal, and sequentially pass through the first bundle, the second bundle, and the fifth bundle to send the PDSCH repetition block and the DMRS to the terminal, so that the terminal can receive the PDSCH repetition block and the DMRS from each bundle based on the beamforming factor corresponding to each bundle, and further perform channel estimation.

In addition, since the scheduled PDSCH is usually transmitted in a repeated manner, for example, the same traffic data block is repeatedly transmitted 4 times, each time being called a repeated block, one repeated block occupying several Orthogonal Frequency Division Multiplexing (Orthogonal Frequency Division Multiplexing) symbols; of course, the repeated transmission may be a repetition of the transmission symbol, or a repetition of different redundancy versions.

In this case, when the base station transmits the DMRS to the terminal on the PDSCH bandwidth for the PDSCH repeated block that is repeatedly transmitted, the transmission scheme may include any one of the following two schemes:

first, multiple PDSCH repeated blocks are transmitted to a terminal over a PDSCH bandwidth, and a DMRS is transmitted at the same OFDM symbol position in each PDSCH repeated block.

Specifically, in this scheme, when the base station transmits PDSCH repeated blocks to the terminal over the PDSCH bandwidth, the base station transmits DMRS to the terminal by transmitting DMRS at the same OFDM symbol position in each PDSCH repeated block.

For example, as shown in fig. 2, assuming that there are 4 PDSCH repeating blocks in total, the base station transmits DMRSs at the same OFDM symbol positions of PDSCH repeating block #1, PDSCH repeating block #2, PDSCH repeating block #3, and PDSCH repeating block #4, that is, DMRSs are distributed at the same positions in each PDSCH repeating block.

Secondly, a plurality of PDSCH repeating blocks are transmitted to the terminal on the PDSCH bandwidth, and the DMRS is transmitted in a centralized manner on OFDM symbol positions at the front ends of all the PDSCH repeating blocks.

Specifically, in this manner, when the base station transmits the PDSCH repeated blocks to the terminal over the PDSCH bandwidth, the base station transmits the DMRS to the terminal by intensively transmitting the DMRSs at the OFDM symbol positions at the front ends of all the PDSCH repeated blocks, that is, by centralizing the DMRSs originally dispersed in each time slot to the foremost OFDM symbol, so that the terminal can receive all the DMRSs first when receiving service data (PDSCH repeated blocks), and thus the terminal can calculate and feed back channel state information earlier, thereby improving the feedback speed of the channel state information.

For example, as shown in fig. 3, assuming that there are 4 PDSCH repeating blocks in total, the base station transmits DMRS collectively at the foremost OFDM symbol positions of PDSCH repeating block #1, PDSCH repeating block #2, PDSCH repeating block #3, and PDSCH repeating block #4, thereby enabling the terminal to perform calculation and feedback of channel state information at an earlier time; in addition, even if the PDSCH reception procedure of the terminal is ended in advance, the calculation of the channel state information is not affected at this time based on having received all DMRSs.

In this way, the base station in this embodiment sends the DMRS to the terminal on the PDSCH bandwidth, where the DMRS bandwidth is greater than or equal to the PDSCH bandwidth, and then receives the channel state information on the entire PDSCH bandwidth, which is fed back by the terminal and acquired based on the DMRS, so that the channel state is calculated and fed back by using the DMRS instead of the CSIRS, and based on the DMRS bandwidth being greater than or equal to the PDSCH bandwidth, the terminal can acquire the channel state information on the entire PDSCH bandwidth, so that the terminal can more accurately feed back the channel state on its scheduling bandwidth, the feedback accuracy of the physical channel state is improved, and the channel state feedback requirement of the URLLC service is satisfied.

In addition, as shown in fig. 4, a flowchart of the steps of the feedback method for channel state information applied to a terminal in the embodiment of the present invention is shown, where the method includes the following steps:

step 401: receiving the DMRS transmitted by the base station on the PDSCH bandwidth.

Specifically, the DMRS bandwidth is greater than or equal to the PDSCH bandwidth.

In this step, specifically, the terminal receives a DMRS, which is transmitted by the base station on the PDSCH bandwidth and has a bandwidth greater than or equal to the PDSCH bandwidth.

The terminal can acquire the channel state information on the whole PDSCH bandwidth when calculating the channel state information through the DMRS by receiving the DMRS of which the bandwidth is greater than or equal to the PDSCH bandwidth, so that the terminal can more accurately feed back the channel state on the scheduling bandwidth of the terminal, and the feedback accuracy of the physical channel state is improved.

Step 402: and acquiring channel state information on the whole PDSCH bandwidth according to the received DMRS.

In this step, specifically, the terminal acquires the channel state information on the whole PDSCH bandwidth according to the received DMRS, so that the terminal can more accurately feed back the channel state on its scheduling bandwidth.

Step 403: and feeding back the channel state information to the base station.

In this step, specifically, after acquiring the channel state information on the entire PDSCH bandwidth, the terminal sends the acquired channel state information to the base station.

At this time, the channel state information is the channel state information on the whole PDSCH bandwidth, and has higher calculation accuracy, so that the base station can better send downlink data to the terminal according to the received channel state information.

In addition, specifically, before receiving the DMRS sent by the base station on the PDSCH bandwidth, the terminal may further receive semi-static configuration information sent by the base station through an RRC message, where the semi-static configuration information includes a DMRS configured by the base station to the terminal, and a bandwidth configuration relationship that the DMRS bandwidth is greater than or equal to the PDSCH bandwidth.

It should be noted that the semi-static configuration information is the same as the semi-static configuration information in the base station side embodiment, and detailed description of the semi-static configuration information is not repeated here.

In addition, specifically, before receiving the DMRS sent by the base station on the PDSCH bandwidth, the terminal may also receive scheduling information sent by the base station through the DCI, where the scheduling information includes bandwidth information of the PDSCH.

It should be noted that the scheduling information is the same as the scheduling information in the foregoing embodiment of the base station side, and details of the scheduling information are not described herein again.

Furthermore, in this embodiment, when receiving the DMRS transmitted by the base station on the PDSCH bandwidth, the terminal may receive the DMRS in any one of the following two manners:

firstly, receiving a part or all of PDSCH repeated blocks transmitted by a base station on a PDSCH bandwidth, and receiving a DMRS transmitted on the same OFDM symbol position of each PDSCH repeated block in the part or all of PDSCH repeated blocks.

Specifically, when the base station transmits the DMRS at the same OFDM symbol position in the PDSCH repetition block, the terminal receives a part or all of the PDSCH repetition block transmitted by the base station over the PDSCH bandwidth and receives the DMRS transmitted at the same OFDM symbol position of each PDSCH repetition block in the part or all of the PDSCH repetition block.

It should be noted that the DMRS distribution manner in this manner may refer to the DMRS distribution manner in this transmission manner in the base station side embodiment, and details of the same contents are not repeated here.

And secondly, receiving partial or all PDSCH repeating blocks transmitted by the base station on the PDSCH bandwidth, and receiving the DMRS transmitted in a centralized manner on OFDM symbol positions at the front ends of all PDSCH repeating blocks.

Specifically, when the base station transmits the DMRS at the OFDM symbol positions at the front ends of all the PDSCH repeating blocks, the terminal receives part or all of the PDSCH repeating blocks transmitted by the base station over the PDSCH bandwidth and receives the DMRS that is transmitted in a concentrated manner at the OFDM symbol positions at the front ends of all the PDSCH repeating blocks.

At this time, based on that the terminal firstly receives all DMRSs when receiving the PDSCH repeating block, under an optimal condition, the terminal can perform channel estimation on all PDSCH bandwidths by only receiving a plurality of front-end OFDM symbols, and then obtain and feed back channel state information to the base station, thereby realizing that the terminal can perform calculation and feedback of the channel state information at an earlier time; in addition, even if the PDSCH receiving process of the terminal is ended in advance, the calculation of the channel state information is not influenced, and the accuracy of the channel state information is ensured.

In addition, specifically, when receiving a part or all of the PDSCH repeated blocks transmitted by the base station on the PDSCH bandwidth, the terminal may detect whether the currently received PDSCH repeated block can be correctly decoded, so as to determine whether to receive the part or all of the PDSCH repeated blocks.

At this time, when the currently received PDSCH repeated block can be correctly decoded, the reception of the remaining PDSCH repeated blocks is stopped; of course, when the currently received PDSCH repeated block cannot be correctly decoded, the remaining PDSCH repeated blocks continue to be received until the currently received PDSCH repeated block can be correctly decoded or all PDSCH repeated blocks are completely received.

For example, referring to fig. 2 or fig. 3, when receiving consecutive PDSCH repeated blocks, the terminal needs to demodulate the received PDSCH repeated blocks one by one, and at this time, as long as one of the PDSCH repeated blocks can contend for decoding, the terminal may stop receiving, for example, when receiving PDSCH repeated block #2 and being able to decode correctly, the terminal may not receive subsequent PDSCH repeated block #3 and PDSCH repeated block #4 any more, so as to enable to respond to the base station in advance, and save end-to-end delay.

It should be noted that, in the case of receiving the partial PDSCH repeating block, the above-mentioned method of receiving DMRSs that are transmitted in a concentrated manner at OFDM symbol positions at the front end of all PDSCH repeating blocks can ensure that all DMRSs are received and applied to the calculation of channel state information, that is, the channel state information obtained by this method is more accurate than that obtained by another method.

In addition, further, when receiving the DMRS transmitted by the base station on the PDSCH bandwidth, the terminal in this embodiment may include any one of the following two manners:

the first method is as follows: and the receiving base station forms the transmitted PDSCH repeated block and the DMRS through the same wave beam on the PDSCH bandwidth.

In this manner, specifically, when the base station transmits the PDSCH repetition block and the DMRS to the terminal through the same beamforming on the PDSCH bandwidth, the terminal receives the PDSCH repetition block and the DMRS transmitted by the base station through the same beamforming on the PDSCH bandwidth.

It should be noted that, in this manner, reference may be made to a manner in which the PDSCH repetition block and the DMRS are sent to the terminal through the same beamforming in the embodiment on the base station side, and details of the same contents are not repeated here.

In addition, specifically, in this manner, when the terminal acquires the channel state information on the entire PDSCH bandwidth according to the received DMRS, the terminal may perform frequency domain filtering channel estimation on the entire PDSCH bandwidth according to the received DMRS to obtain a first channel estimation result of the entire PDSCH bandwidth, and obtain the channel state information according to the first channel estimation result.

At this time, when the first channel estimation result is obtained, any one of the following two ways may be used:

1) calculating a zero forcing result on each Resource Block (RB) corresponding to the DMRS according to the received DMRS, and carrying out average operation on the calculated zero forcing results to obtain an average value; and performing frequency domain filtering channel estimation on the whole PDSCH bandwidth according to the average value to obtain a first channel estimation result.

2) Calculating a zero forcing result on each RB corresponding to the DMRS according to the received DMRS, and performing frequency domain filtering channel estimation on each RB according to the zero forcing result of each RB to obtain a frequency domain filtering channel estimation result corresponding to each RB; and then carrying out average operation on the frequency domain filtering channel estimation result obtained by calculation to obtain a first channel estimation result.

That is, in this embodiment, the frequency domain filtering channel estimation may be performed on the entire PDSCH bandwidth based on the received DMRS in any manner described above, so as to obtain the first channel estimation result of the entire PDSCH bandwidth.

The second method comprises the following steps: and receiving a beam forming factor corresponding to the bundle sent by the base station, and receiving the PDSCH repeated block and the DMRS sent by the base station by using different beam forming modes with the bundle as a unit according to the beam forming factor.

In this manner, specifically, when the base station uses a bundle as a unit to transmit the PDSCH repetition block and the DMRS to the terminal in different beamforming manners, the terminal may receive the PDSCH repetition block and the DMRS transmitted by the base station in different beamforming manners using a bundle as a unit according to a beamforming factor corresponding to the bundle.

It should be noted that, in this manner, reference may be made to a manner in which different beamforming manners are used in a base station side embodiment by taking a bundle as a unit to transmit a PDSCH repetition block and a DMRS to a terminal, and details of the same contents are not repeated here.

In addition, specifically, in this manner, when the terminal acquires the channel state information on the whole PDSCH bandwidth according to the received DMRS, the terminal may perform frequency domain filtering channel estimation on each bundle according to the received DMRS to obtain a second channel estimation result corresponding to each bundle; and then obtaining a third channel estimation result of the whole PDSCH bandwidth according to the second channel estimation result corresponding to each bundle, and obtaining channel state information according to the third channel estimation result.

That is, in this embodiment, for different receiving manners of DMRSs, the channel state information may be acquired in a corresponding manner.

In this way, the terminal in this embodiment receives the DMRS sent by the base station on the PDSCH bandwidth, and the DMRS bandwidth is greater than or equal to the PDSCH bandwidth, so that the terminal can obtain the channel state information on the entire PDSCH bandwidth according to the received DMRS, thereby ensuring that the terminal can more accurately feed back the channel state on its scheduling bandwidth, and making the channel state feedback mode in this embodiment better than the existing CSIRS feedback mode.

The following describes an interaction process in the present embodiment by way of example.

Referring to fig. 5, first, a base station transmits semi-static configuration information to a terminal, where the semi-static configuration information includes a DMRS configured to the terminal and a bandwidth configuration relationship that a DMRS bandwidth is greater than or equal to a PDSCH bandwidth;

then, when URLLC downlink service needs to be scheduled, the base station sends scheduling information to the terminal through DCI, wherein the scheduling information comprises bandwidth information of a PDSCH, and the bandwidth information comprises channel bandwidth and resource position of the PDSCH, and configuration information such as initial PDSCH modulation level, code rate, shaping and the like;

then, the base station sends the PDSCH repetition block and the DMRS to the terminal; the method comprises two transmission modes: firstly, as shown in fig. 2, DMRS is distributed at the same OFDM symbol position in each PDSCH repeating block, and at this time, the terminal receives a plurality of PDSCH repeating blocks in sequence, merges the subsequently received PDSCH repeating blocks with the previously received PDSCH repeating blocks, demodulates and decodes the PDSCH repeating blocks; secondly, as shown in fig. 3, DMRS is concentrated at the foremost position of all PDSCH repeated blocks, which is beneficial for the terminal to perform channel estimation and calculation of channel state at an earlier time; in addition, when the terminal receives the continuous PDSCH repeated blocks, the DMRS is received firstly, combined channel estimation is carried out by using the DMRS for multiple times, then the PDSCH repeated blocks are demodulated one by one, and the reception is stopped as long as one PDSCH repeated block can be decoded correctly, so that the terminal can respond to the base station in advance, and the end-to-end time delay is saved;

then, the terminal calculates information state information on the PDSCH bandwidth according to the received DMRS;

then, the terminal feeds back the calculated channel state information to the base station, and at this time, as described above, since the terminal may feed back after correctly decoding the previous PDSCH repeated blocks, the method of fig. 3 can ensure that all DMRSs can be received and applied to the calculation of the channel state information, that is, the channel state information obtained by the method is more accurate;

and then, after receiving the channel state information of the terminal, the base station continuously schedules subsequent PDSCH data information according to the channel state information and transmits the DMRS, wherein the DMRS comprises the steps of updating a modulation mode, a shaped vector, the number of the number streams and the like.

In this way, as the DMRS is used for feeding back the channel state information, and the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH, the terminal can feed back the channel state on the scheduling bandwidth more accurately, the adaptation degree is higher than that of the existing CSIRS feedback method, and the pilot density of the DMRS is higher than that of the CSIRS, so that the accuracy of the obtained channel state information is higher, and the time delay required for calculation is shorter.

In addition, as shown in fig. 6, a block diagram of a feedback apparatus for channel state information applied to a base station in an embodiment of the present invention is shown, where the apparatus includes:

a sending module 601, configured to send a demodulation reference signal DMRS to a terminal on a PDSCH bandwidth of a physical downlink shared channel, where the DMRS bandwidth is greater than or equal to the PDSCH bandwidth, so that the terminal obtains channel state information on the entire PDSCH bandwidth according to the received DMRS;

a receiving module 602, configured to receive the channel state information fed back by the terminal.

Optionally, the sending module 601 includes:

a first transmitting unit, configured to transmit, to a terminal, a PDSCH repetition block and a DMRS through the same beamforming on the PDSCH bandwidth; or,

and a second sending unit, configured to send a beamforming factor corresponding to the bandwidth bonding block bundle to the terminal, and send the PDSCH repetition block and the DMRS to the terminal in different beamforming manners with the bundle as a unit.

Optionally, the sending module 601 includes:

a third transmitting unit, configured to transmit a plurality of PDSCH repeating blocks to the terminal over the PDSCH bandwidth, and to transmit a DMRS at a same orthogonal frequency division multiplexing, OFDM, symbol position in each PDSCH repeating block; or,

and a fourth transmitting unit, configured to transmit a plurality of PDSCH repeated blocks to the terminal over the PDSCH bandwidth, and transmit the DMRS collectively at OFDM symbol positions at front ends of all PDSCH repeated blocks.

It should be noted that the apparatus in this embodiment can implement all the method steps of the method embodiment on the base station side, and can implement the same technical effect, and the description of the same parts in this embodiment and the method embodiment is not repeated here.

In addition, as shown in fig. 7, a block diagram of a feedback apparatus for channel state information applied to a terminal in an embodiment of the present invention is shown, where the apparatus includes:

a receiving module 701, configured to receive a demodulation reference signal DMRS sent by a base station on a PDSCH bandwidth of a physical downlink shared channel, where the DMRS bandwidth is greater than or equal to the PDSCH bandwidth;

an obtaining module 702, configured to obtain channel state information on a whole PDSCH bandwidth according to the received DMRS;

a sending module 703, configured to feed back the channel state information to the base station.

Optionally, the receiving module 701 includes:

a first receiving unit, configured to receive part or all of PDSCH repeating blocks transmitted by the base station on the PDSCH bandwidth, and receive a DMRS transmitted at a same orthogonal frequency division multiplexing, OFDM, symbol position of each PDSCH repeating block in the part or all of PDSCH repeating blocks; or,

and a second receiving unit, configured to receive a part or all of the PDSCH repeated blocks sent by the base station over the PDSCH bandwidth, and receive the DMRS that is sent in a centralized manner at OFDM symbol positions at the front ends of all the PDSCH repeated blocks.

It should be noted that the apparatus in this embodiment can implement all the method steps of the method embodiment at the terminal side and can implement the same technical effect, and the description of the same parts in this embodiment and the method embodiment is not repeated here.

In addition, as shown in fig. 8, an entity structure diagram of a base station provided in the embodiment of the present invention is shown, where the base station may include: a processor (processor)810, a transceiver (Communications Interface)820, a memory (memory)830 and a communication bus 840, wherein the processor 810, the transceiver 820 and the memory 830 communicate with each other via the communication bus 840. The processor 810 may invoke a computer program stored on the memory 830 and executable on the processor 810 to perform the following steps:

sending a demodulation reference signal (DMRS) to a terminal on the bandwidth of a Physical Downlink Shared Channel (PDSCH), wherein the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH, so that the terminal can acquire channel state information on the bandwidth of the whole PDSCH according to the received DMRS; and receiving the channel state information fed back by the terminal.

Optionally, the sending, to the terminal, a demodulation reference signal DMRS on a bandwidth of a physical downlink shared channel PDSCH includes: transmitting a PDSCH repetition block and a DMRS to a terminal through the same beamforming on the PDSCH bandwidth; or, a beam forming factor corresponding to a bandwidth binding block bundle is sent to the terminal, and a PDSCH repetition block and a DMRS are sent to the terminal by using the bundle as a unit and using different beam forming modes.

Optionally, the sending, to the terminal, a demodulation reference signal DMRS on a bandwidth of a physical downlink shared channel PDSCH includes: transmitting a plurality of PDSCH repeating blocks to the terminal over the PDSCH bandwidth, and transmitting a DMRS at the same Orthogonal Frequency Division Multiplexing (OFDM) symbol position in each PDSCH repeating block; or, transmitting a plurality of PDSCH repeating blocks to the terminal on the PDSCH bandwidth, and transmitting the DMRS in a centralized manner on OFDM symbol positions at the front ends of all the PDSCH repeating blocks.

Optionally, before the sending the demodulation reference signal DMRS to the terminal on the bandwidth of the physical downlink shared channel PDSCH, the method further includes: sending semi-static configuration information to a terminal through a Radio Resource Control (RRC) message, wherein the semi-static configuration information comprises a DMRS configured to the terminal and a bandwidth configuration relation that the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH.

Optionally, before the sending the demodulation reference signal DMRS to the terminal on the bandwidth of the physical downlink shared channel PDSCH, the method further includes: and when a high-reliability low-delay URLLC downlink service needs to be scheduled, sending scheduling information to the terminal through downlink control information DCI, wherein the scheduling information comprises the bandwidth information of the PDSCH.

In addition, the logic instructions in the memory 830 may be implemented in software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk, and various media capable of storing program codes.

In addition, as shown in fig. 9, an entity structure diagram of a terminal provided in the embodiment of the present invention is shown, where the terminal may include: a processor (processor)910, a transceiver (Communications Interface)920, a memory (memory)930, and a communication bus 940, wherein the processor 910, the transceiver 920, and the memory 930 communicate with each other via the communication bus 940. The processor 910 may invoke a computer program stored on the memory 930 and executable on the processor 910 to perform the steps of:

receiving a demodulation reference signal DMRS (demodulation reference signal) sent by a base station on the bandwidth of a Physical Downlink Shared Channel (PDSCH), wherein the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH; acquiring channel state information on the whole PDSCH bandwidth according to the received DMRS; and feeding back the channel state information to a base station.

Optionally, the receiving a demodulation reference signal DMRS sent by a base station on a bandwidth of a physical downlink shared channel PDSCH includes: receiving a part or all of PDSCH repeated blocks transmitted by the base station on the PDSCH bandwidth, and receiving a DMRS transmitted on the same Orthogonal Frequency Division Multiplexing (OFDM) symbol position of each PDSCH repeated block in the part or all of PDSCH repeated blocks; or receiving part or all of the PDSCH repeating blocks transmitted by the base station on the PDSCH bandwidth, and receiving the DMRS transmitted in a centralized manner at OFDM symbol positions at the front ends of all the PDSCH repeating blocks.

Optionally, the receiving a part or all of the PDSCH repeated blocks transmitted by the base station on the PDSCH bandwidth includes: when the currently received PDSCH repeated block can be correctly decoded, stopping receiving the rest PDSCH repeated blocks; and when the currently received PDSCH repeated block can not be correctly decoded, continuously receiving the rest PDSCH repeated blocks until the currently received PDSCH repeated block can be correctly decoded or all PDSCH repeated blocks are completely received.

Optionally, the receiving a demodulation reference signal DMRS sent by a base station on a bandwidth of a physical downlink shared channel PDSCH includes: receiving a PDSCH repeating block and a DMRS which are sent by the base station through the same beamforming on the PDSCH bandwidth; or receiving a beam forming factor corresponding to a bandwidth binding block bundle sent by the base station, and receiving a PDSCH repetition block and a DMRS sent by the base station by using the bundle as a unit and adopting different beam forming modes according to the beam forming factor.

Optionally, the acquiring channel state information over the entire PDSCH bandwidth according to the received DMRS includes: when receiving a PDSCH repeating block and a DMRS which are sent by the base station through the same beamforming on the PDSCH bandwidth, performing frequency domain filtering channel estimation on the whole PDSCH bandwidth according to the received DMRS to obtain a first channel estimation result of the whole PDSCH bandwidth, and obtaining the channel state information according to the first channel estimation result; or, when receiving the PDSCH repetition block and the DMRS which are sent by the base station by using different beamforming modes with the bundle as a unit, performing frequency domain filtering channel estimation on each bundle according to the received DMRS to obtain a second channel estimation result corresponding to each bundle; and obtaining a third channel estimation result of the whole PDSCH bandwidth according to the second channel estimation result corresponding to each bundle, and obtaining the channel state information according to the third channel estimation result.

Optionally, the performing, by the received DMRS, frequency-domain filtering channel estimation on the entire PDSCH bandwidth to obtain a first channel estimation result of the entire PDSCH bandwidth includes:

calculating a zero forcing result on each resource block RB corresponding to the DMRS according to the received DMRS, and carrying out average operation on the calculated zero forcing results to obtain an average value; performing frequency domain filtering channel estimation on the whole PDSCH bandwidth according to the average value to obtain the first channel estimation result; or calculating a zero forcing result on each RB corresponding to the DMRS according to the received DMRS, and performing frequency domain filtering channel estimation on each RB according to the zero forcing result of each RB to obtain a frequency domain filtering channel estimation result corresponding to each RB; and carrying out average operation on the frequency domain filtering channel estimation result obtained by calculation to obtain the first channel estimation result.

Optionally, before the receiving the DMRS sent by the base station on the bandwidth of the physical downlink shared channel PDSCH, the method further includes: receiving semi-static configuration information sent by the base station through a Radio Resource Control (RRC) message, wherein the semi-static configuration information comprises a DMRS configured by the base station to the terminal, and a bandwidth configuration relation that the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH.

Optionally, before the receiving the DMRS sent by the base station on the bandwidth of the physical downlink shared channel PDSCH, the method further includes: and receiving scheduling information sent by the base station through Downlink Control Information (DCI), wherein the scheduling information comprises bandwidth information of the PDSCH.

Furthermore, the logic instructions in the memory 930 may be implemented in software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

Embodiments of the present invention also provide a non-transitory computer-readable storage medium, on which a computer program is stored, and the computer program, when executed by a processor, implements the methods provided by the above embodiments.

It should be noted that, the non-transitory computer-readable storage medium in this embodiment can implement all the method steps of the above method embodiments, and can implement the same technical effects, and the description of the same parts in this embodiment and the method embodiments is not repeated here.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment may be implemented by software plus a necessary general hardware platform, and may also be implemented by hardware. Based on the understanding, the above technical solutions substantially or otherwise contributing to the prior art may be embodied in the form of a software product, which may be stored in a computer-readable storage medium, such as ROM/RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method according to the various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A feedback method of channel state information is applied to a base station, and is characterized by comprising the following steps:

and receiving the channel state information fed back by the terminal.

2. The method for feeding back channel state information according to claim 1, wherein the sending a demodulation reference signal (DMRS) to the terminal on a bandwidth of a Physical Downlink Shared Channel (PDSCH) comprises:

transmitting a PDSCH repetition block and a DMRS to a terminal through the same beamforming on the PDSCH bandwidth; or,

and sending a beam forming factor corresponding to the bandwidth binding block bundle to the terminal, and sending the PDSCH repetition block and the DMRS to the terminal by using the bundle as a unit and adopting different beam forming modes.

3. The method for feeding back channel state information according to claim 1, wherein the sending a demodulation reference signal DMRS to a terminal on a physical downlink shared channel PDSCH bandwidth comprises:

transmitting a plurality of PDSCH repeating blocks to the terminal over the PDSCH bandwidth, and transmitting a DMRS at the same Orthogonal Frequency Division Multiplexing (OFDM) symbol position in each PDSCH repeating block; or,

and transmitting a plurality of PDSCH repeated blocks to the terminal on the PDSCH bandwidth, and transmitting the DMRS in a centralized manner on OFDM symbol positions at the front ends of all the PDSCH repeated blocks.

4. The method for feeding back channel state information according to claim 1, wherein before the sending a demodulation reference signal DMRS to a terminal on a physical downlink shared channel PDSCH bandwidth, the method further comprises:

sending semi-static configuration information to a terminal through a Radio Resource Control (RRC) message, wherein the semi-static configuration information comprises a DMRS configured to the terminal and a bandwidth configuration relation that the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH.

5. The method for feeding back channel state information according to claim 1, wherein before the sending a demodulation reference signal DMRS to a terminal on a physical downlink shared channel PDSCH bandwidth, the method further comprises:

and when a high-reliability low-delay URLLC downlink service needs to be scheduled, sending scheduling information to the terminal through downlink control information DCI, wherein the scheduling information comprises the bandwidth information of the PDSCH.

6. A feedback method of channel state information is applied to a terminal, and is characterized by comprising the following steps:

and feeding back the channel state information to a base station.

7. The method for feeding back channel state information according to claim 6, wherein the receiving of the DMRS transmitted by the base station on the bandwidth of the PDSCH comprises:

receiving a part or all of PDSCH repeated blocks transmitted by the base station on the PDSCH bandwidth, and receiving a DMRS transmitted on the same Orthogonal Frequency Division Multiplexing (OFDM) symbol position of each PDSCH repeated block in the part or all of PDSCH repeated blocks; or,

and receiving part or all of PDSCH repeated blocks transmitted by the base station on the PDSCH bandwidth, and receiving the DMRS transmitted in a centralized manner at OFDM symbol positions at the front ends of all the PDSCH repeated blocks.

8. The method of claim 7, wherein the receiving of the part or all of the PDSCH repeated blocks transmitted by the base station on the PDSCH bandwidth comprises:

when the currently received PDSCH repeated block can be correctly decoded, stopping receiving the rest PDSCH repeated blocks;

and when the currently received PDSCH repeated block can not be correctly decoded, continuously receiving the rest PDSCH repeated blocks until the currently received PDSCH repeated block can be correctly decoded or all PDSCH repeated blocks are completely received.

9. The method for feeding back channel state information according to claim 6, wherein the receiving of the DMRS transmitted by the base station on the bandwidth of the PDSCH comprises:

receiving a PDSCH repeating block and a DMRS which are sent by the base station through the same beamforming on the PDSCH bandwidth; or,

and receiving a beam forming factor corresponding to a bandwidth binding block bundle sent by the base station, and receiving a PDSCH repetition block and a DMRS which are sent by the base station in different beam forming modes by taking the bundle as a unit according to the beam forming factor.

10. The method for feeding back channel state information according to claim 9, wherein the obtaining channel state information over the entire PDSCH bandwidth according to the received DMRS comprises:

when receiving a PDSCH repeating block and a DMRS which are sent by the base station through the same beamforming on the PDSCH bandwidth, performing frequency domain filtering channel estimation on the whole PDSCH bandwidth according to the received DMRS to obtain a first channel estimation result of the whole PDSCH bandwidth, and obtaining the channel state information according to the first channel estimation result; or,

when receiving a PDSCH repetition block and a DMRS which are sent by the base station by using different beamforming modes with the bundle as a unit, performing frequency domain filtering channel estimation on each bundle according to the received DMRS to obtain a second channel estimation result corresponding to each bundle;

and obtaining a third channel estimation result of the whole PDSCH bandwidth according to the second channel estimation result corresponding to each bundle, and obtaining the channel state information according to the third channel estimation result.

11. The method of claim 10, wherein the performing frequency-domain filtering channel estimation on the entire PDSCH bandwidth through the received DMRS to obtain a first channel estimation result of the entire PDSCH bandwidth comprises:

calculating a zero forcing result on each resource block RB corresponding to the DMRS according to the received DMRS, and carrying out average operation on the calculated zero forcing results to obtain an average value;

performing frequency domain filtering channel estimation on the whole PDSCH bandwidth according to the average value to obtain the first channel estimation result;

or,

calculating a zero forcing result on each RB corresponding to the DMRS according to the received DMRS, and performing frequency domain filtering channel estimation on each RB according to the zero forcing result of each RB to obtain a frequency domain filtering channel estimation result corresponding to each RB;

and carrying out average operation on the frequency domain filtering channel estimation result obtained by calculation to obtain the first channel estimation result.

12. The method for feeding back channel state information according to claim 6, wherein the receiving base station further includes, before the demodulation reference signal DMRS that is transmitted on the physical downlink shared channel PDSCH bandwidth:

receiving semi-static configuration information sent by the base station through a Radio Resource Control (RRC) message, wherein the semi-static configuration information comprises a DMRS configured by the base station to the terminal, and a bandwidth configuration relation that the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH.

13. The method for feeding back channel state information according to claim 6, wherein the receiving base station further includes, before the demodulation reference signal DMRS that is transmitted on the physical downlink shared channel PDSCH bandwidth:

and receiving scheduling information sent by the base station through Downlink Control Information (DCI), wherein the scheduling information comprises bandwidth information of the PDSCH.

14. A feedback device of channel state information is applied to a base station, and is characterized by comprising:

15. A feedback device of channel state information is applied to a terminal, and is characterized by comprising:

the base station comprises a receiving module and a processing module, wherein the receiving module is used for receiving a demodulation reference signal DMRS (demodulation reference signal) sent by the base station on the bandwidth of a Physical Downlink Shared Channel (PDSCH), and the bandwidth of the DMRS is greater than or equal to the bandwidth of the PDSCH;

16. A base station comprising a memory, a processor, and a program stored on the memory and executable on the processor, wherein the processor when executing the program performs the steps of:

and receiving the channel state information fed back by the terminal.

17. The base station of claim 16, wherein the transmitting a demodulation reference signal (DMRS) to a terminal on a bandwidth of a Physical Downlink Shared Channel (PDSCH) comprises:

18. The base station of claim 16, wherein the transmitting a demodulation reference signal (DMRS) to the terminal on a bandwidth of a Physical Downlink Shared Channel (PDSCH) comprises:

19. The base station of claim 16, wherein before the sending of the demodulation reference signal DMRS to the terminal on the physical downlink shared channel PDSCH bandwidth, the processor executes the program to further implement the following steps:

20. The base station of claim 16, wherein before the sending of the demodulation reference signal DMRS to the terminal on the physical downlink shared channel PDSCH bandwidth, the processor executes the program to further implement the following steps:

21. A terminal comprising a memory, a processor, and a program stored on the memory and executable on the processor, wherein the processor when executing the program performs the steps of:

and feeding back the channel state information to a base station.

22. The terminal of claim 21, wherein the receiving of the DMRS transmitted by the base station on the physical downlink shared channel PDSCH bandwidth comprises:

23. The terminal of claim 22, wherein the receiving of some or all of the PDSCH repeating blocks transmitted by the base station over the PDSCH bandwidth comprises:

24. The terminal of claim 21, wherein the receiving of the DMRS transmitted by the base station on the physical downlink shared channel PDSCH bandwidth comprises:

25. The terminal of claim 24, wherein the obtaining channel state information over the entire PDSCH bandwidth based on the received DMRS comprises:

when receiving PDSCH repeating blocks and DMRS which are sent by the base station by using different beam forming modes with bundle as a unit, performing frequency domain filtering channel estimation on each bundle according to the received DMRS to obtain a second channel estimation result corresponding to each bundle;

26. The terminal of claim 25, wherein the performing frequency domain filtering channel estimation on the entire PDSCH bandwidth through the received DMRS to obtain a first channel estimation result for the entire PDSCH bandwidth comprises:

or,

27. The terminal of claim 21, wherein the processor executes the program to further implement the following steps before the base station receives a DMRS transmitted on a Physical Downlink Shared Channel (PDSCH) bandwidth by the base station:

28. The terminal of claim 21, wherein the processor executes the program to further implement the following steps before the base station receives a DMRS transmitted on a Physical Downlink Shared Channel (PDSCH) bandwidth by the base station:

29. A non-transitory computer readable storage medium, having stored thereon a computer program, which, when being executed by a processor, implements the steps of the method for feedback of channel state information according to any one of claims 1 to 13.