WO2018028397A1

WO2018028397A1 - Resource mapping method utilized in reference signal demodulation, base station, terminal, and data storage medium

Info

Publication number: WO2018028397A1
Application number: PCT/CN2017/093412
Authority: WO
Inventors: 林祥利; 高雪娟; 潘学明
Original assignee: 电信科学技术研究院
Priority date: 2016-08-10
Filing date: 2017-07-18
Publication date: 2018-02-15
Also published as: CN107733594A; CN107733594B

Abstract

The disclosure provides a resource mapping method utilized in reference signal demodulation, a base station, a terminal, and a data storage medium. The resource mapping method comprises: selecting, in each short transmission time interval (TTI), at least one orthogonal frequency division multiplexing (OFDM) symbol containing no mapped common reference signal (CRS); and mapping, in the selected OFDM symbol, a demodulation reference signal (DMRS).

Description

Resource mapping method for demodulating reference signals, base station, terminal, and storage medium

Cross-reference to related applications

Priority is claimed on Japanese Patent Application No. 201610653706.7, filed on Jan. 10,,,,,,,,,,,,,

Technical field

The present disclosure relates to the technical field of communication applications, and in particular, to a resource mapping method for demodulating reference signals, a base station, a terminal, and a storage medium.

Background technique

With the development of mobile communication services, organizations such as the International Telecommunication Union (ITU) have defined higher user plane delay performance requirements for future mobile communication systems. One of the main ways to shorten the user's delay performance is to reduce the length of the Transmission Time Interval (TTI). In the Long Term Evolution (LTE) system, existing channel transmissions are defined with TTI = 1 ms. When the TTI length is shortened, the number of pilots available for data demodulation is reduced, and the original pilot mapping mode affects channel estimation performance. When shortened to two OFDM (Orthogonal Frequency-division multiplexing) symbols, the original DeModulation Reference Signal (DMRS) resource mapping method cannot make DMRS in each TTI, which has a serious impact on channel estimation performance. And impose restrictions on scheduling. However, for the short TTI downlink, the user-specific reference signal needs to be redesigned. Currently, there is no explicit resource mapping scheme for the downlink user-specific reference signal.

Summary of the invention

An object of the present disclosure is to provide a resource mapping method, a base station, and a terminal for demodulating a reference signal, which are used to solve the problem that when the TTI length is shortened, the original pilot mapping manner cannot include DMRS in each TTI, thereby affecting the channel. Estimate performance issues.

In order to achieve the above object, the present disclosure provides a resource mapping method for demodulating a reference signal, include:

In each short transmission time interval TTI, selecting at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS;

A demodulation reference signal DMRS is mapped in the selected OFDM symbol.

The step of selecting at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS in each short transmission time interval TTI includes:

If the length of the short TTI is the length of time corresponding to two OFDM symbols, in each of the short TTIs, one OFDM symbol of the unmapped CRS is selected.

If the length of the short TTI is the length of time corresponding to the two OFDM symbols, in each of the short TTIs, the step of selecting an OFDM symbol that does not map the CRS includes:

If each subframe includes 14 OFDM symbols, selecting a third OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a third OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.

The number of antenna ports of the DMRS is up to 4;

The step of mapping the demodulation reference signal DMRS in the selected OFDM symbol includes:

If one resource block RB or 12 subcarriers are used as a unit in the frequency domain, mapping is performed in the second subcarrier, the third subcarrier, the eighth subcarrier, and the ninth subcarrier in each selected OFDM symbol. DMRS; or

Mapping the DMRS in the second subcarrier, the fifth subcarrier, the eighth subcarrier, and the twelfth subcarrier in each selected OFDM symbol; or

The first subcarrier, the second subcarrier, and the ninth in each selected OFDM symbol The DMRS is mapped in the subcarrier and the 10th subcarrier.

The number of antenna ports of the DMRS is up to 8;

If one RB or 12 subcarriers are used as a unit in the frequency domain, the second subcarrier, the third subcarrier, the fourth subcarrier, the fifth subcarrier, and the eighth subcarrier in each selected OFDM symbol Mapping the DMRS in the carrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier; or

In the first subcarrier, the second subcarrier, the fourth subcarrier, the fifth subcarrier, the seventh subcarrier, the eighth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Map DMRS; or

In the first subcarrier, the second subcarrier, the third subcarrier, the fourth subcarrier, the ninth subcarrier, the tenth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Map DMRS.

If the length of the short TTI is the length of time corresponding to the seven OFDM symbols, at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS is selected according to the maximum value of the number of antenna ports of the DMRS.

If the length of the short TTI is the length of time corresponding to the seven OFDM symbols, the orthogonal frequency division of at least one unmapped common pilot CRS is selected according to the maximum value of the number of antenna ports of the DMRS. The steps of using OFDM symbols include:

If the number of antenna ports of the DMRS is at most 4, in each of the short TTIs, at least one OFDM symbol that does not map the common pilot CRS is selected.

If the number of antenna ports of the DMRS is at most 4, in each of the short TTIs, the step of selecting at least one OFDM symbol that does not map the common pilot CRS includes:

In each of the short TTIs, selecting a third OFDM symbol and a sixth OFDM symbol; or

In each of the short TTIs, selecting a fourth OFDM symbol and a sixth OFDM symbol; or

In each of the short TTIs, selecting a third OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, selecting a fourth OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol is selected; or

In each of the short TTIs, the 7th OFDM symbol is selected.

If the number of antenna ports of the DMRS is at most 8, in each of the short TTIs, at least two OFDM symbols not mapped with a common pilot CRS are selected.

If the number of antenna ports of the DMRS is at most 8, the step of selecting at least two OFDM symbols that do not map the common pilot CRS in each of the short TTIs includes:

In each of the short TTIs, selecting a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol and a seventh OFDM symbol are selected.

If one RB or 12 subcarriers are used as a unit in the frequency domain, two or four adjacent subcarrier mapping demodulation reference signals DMRS are selected in each selected OFDM symbol, wherein each subcarrier selected The same frequency domain position is occupied in different OFDM symbols.

The step of selecting two or four adjacent four subcarrier mapping demodulation reference signals DMRS in each selected OFDM symbol includes:

The second subcarrier, the third word carrier, the eighth subcarrier, and the ninth subcarrier mapping demodulation reference signal DMRS are selected in each selected OFDM symbol.

To solve the above technical problem, an embodiment of the present disclosure further provides a base station, including:

a first selecting module, configured to: in each short transmission time interval TTI, select at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS;

a mapping module, configured to map a demodulation reference signal DMRS in the selected OFDM symbol, and Send the DMRS.

The first selection module includes:

And a first selecting submodule, configured to select, in each of the short TTIs, an OFDM symbol that is not mapped to the CRS, if the length of the short TTI is a length of time corresponding to two OFDM symbols.

The first selecting submodule is configured to select a third OFDM symbol and a thirteenth OFDM symbol in each of the subframes if each subframe includes 14 OFDM symbols; or

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.

The mapping module includes:

a first mapping sub-module, where the number of antenna ports for the DMRS is at most 4 and 1 resource block RB or 12 sub-carriers are used as a unit in the frequency domain, and then 2nd in each selected OFDM symbol Mapping DMRSs in subcarriers, 3rd subcarriers, 8th subcarriers, and 9th subcarriers; or

The DMRS is mapped in the first subcarrier, the second subcarrier, the ninth subcarrier, and the tenth subcarrier in each selected OFDM symbol.

The mapping module includes:

a second mapping submodule, where the number of antenna ports for the DMRS is at most 8 and one RB or 12 subcarriers are used as a unit in the frequency domain, and then the second subcarrier in each selected OFDM symbol Mapping the DMRS in the third subcarrier, the fourth subcarrier, the fifth subcarrier, the eighth subcarrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier; or

The first selection module includes:

a second selecting submodule, configured to: if the length of the short TTI is a length of time corresponding to seven OFDM symbols, select at least one unmapped common pilot CRS according to a maximum value of the number of antenna ports of the DMRS The frequency division is divided into OFDM symbols.

The second selection submodule includes:

The first selecting unit is configured to: if each of the short TTIs selects at least one OFDM symbol that does not map the common pilot CRS, if the number of antenna ports of the DMRS is at most 4.

The first selecting unit is configured to select a third OFDM symbol and a sixth OFDM symbol in each of the short TTIs; or

In each of the short TTIs, a sixth OFDM symbol is selected; or

In each of the short TTIs, the 7th OFDM symbol is selected.

The second selection submodule includes:

And a second selecting unit, configured to select at least two OFDM symbols that do not map the common pilot CRS in each of the short TTIs, if the number of antenna ports of the DMRS is at most 8.

The second selecting unit is configured to select, in each of the short TTIs, a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol and a seventh OFDM symbol are selected. The mapping module includes:

a third mapping submodule, configured to select one or two adjacent four subcarrier mapping demodulation reference signals DMRS in each selected OFDM symbol if one RB or 12 subcarriers are used as a unit in the frequency domain, Each of the selected subcarriers occupies the same frequency domain position in different OFDM symbols.

The third mapping submodule is configured to select a second subcarrier, a third word carrier, an eighth subcarrier, and a ninth subcarrier mapping demodulation reference signal DMRS in each selected OFDM symbol.

In order to solve the above technical problem, an embodiment of the present disclosure further provides a terminal, including:

a second selecting module, configured to: in each short transmission time interval TTI, select at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS;

And an obtaining module, configured to obtain, in the selected OFDM symbol, a demodulation reference signal DMRS sent by the base station.

The second selection module includes:

And a third selection submodule, configured to select, in each of the short TTIs, an OFDM symbol that is not mapped to the CRS, if the length of the short TTI is a length of time corresponding to two OFDM symbols.

The third selecting submodule is configured to select a third OFDM symbol and a thirteenth OFDM symbol in each of the subframes if each subframe includes 14 OFDM symbols; or

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.

The obtaining module includes:

a first obtaining submodule, where the number of antenna ports for the DMRS is up to 4 and in a frequency domain Obtaining DMRS sent by the base station in the second subcarrier, the third subcarrier, the eighth subcarrier, and the ninth subcarrier in each selected OFDM symbol by using one resource block RB or 12 subcarriers as one unit ;or

Acquiring the DMRS sent by the base station in the second subcarrier, the fifth subcarrier, the eighth subcarrier, and the twelfth subcarrier in each selected OFDM symbol; or

The DMRS sent by the base station is obtained in the first subcarrier, the second subcarrier, the ninth subcarrier, and the tenth subcarrier in each selected OFDM symbol.

The obtaining module includes:

a second obtaining submodule, where the number of antenna ports for the DMRS is at most 8 and 1 RB or 12 subcarriers are used as a unit in the frequency domain, and then the second subcarrier in each selected OFDM symbol Obtaining, by the third subcarrier, the fourth subcarrier, the fifth subcarrier, the eighth subcarrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier, a DMRS sent by the base station; or

In the first subcarrier, the second subcarrier, the fourth subcarrier, the fifth subcarrier, the seventh subcarrier, the eighth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Obtaining the DMRS sent by the base station; or

In the first subcarrier, the second subcarrier, the third subcarrier, the fourth subcarrier, the ninth subcarrier, the tenth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Obtain the DMRS sent by the base station.

The second selection module includes:

a fourth selecting submodule, configured to: if the length of the short TTI is a length of time corresponding to seven OFDM symbols, select at least one unmapped common pilot CRS according to a maximum value of the number of antenna ports of the DMRS. The frequency division is divided into OFDM symbols.

The fourth selection submodule includes:

And a third selecting unit, configured to: if each of the short TTIs selects at least one OFDM symbol that does not map the common pilot CRS, if the number of antenna ports of the DMRS is at most 4.

The third selecting unit is configured to select a third OFDM symbol and a sixth OFDM symbol in each of the short TTIs; or

In each of the short TTIs, a sixth OFDM symbol is selected; or

In each of the short TTIs, the 7th OFDM symbol is selected.

The fourth selection submodule includes:

And a fourth selecting unit, configured to: if each of the short TTIs selects at least two OFDM symbols that do not map the common pilot CRS, if the number of antenna ports of the DMRS is at most 8.

The fourth selecting unit is configured to select, in each of the short TTIs, a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol and a seventh OFDM symbol are selected. The obtaining module includes:

a third obtaining submodule, configured to: if one RB or 12 subcarriers are used as a unit in the frequency domain, select two adjacent four subcarriers in each selected OFDM symbol to obtain a demodulation reference sent by the base station A signal DMRS, wherein each of the selected subcarriers occupies the same frequency domain position in different OFDM symbols.

The third obtaining submodule is configured to select a second subcarrier, a third word carrier, an eighth subcarrier, and a ninth subcarrier in each selected OFDM symbol to obtain a demodulation reference signal DMRS sent by the base station. .

The embodiment of the present disclosure further provides a base station, including:

Processor;

a transceiver for receiving and transmitting data under the control of the processor,

The processor is configured to do the following:

In each short transmission time interval (TTI), at least one orthogonal frequency division multiplexing (OFDM) symbol that does not map a common pilot (CRS) is selected;

A demodulation reference signal (DMRS) is mapped in the selected OFDM symbol and the DMRS is transmitted.

The embodiment of the present disclosure further provides a terminal, including:

Processor;

The processor is configured to do the following:

A demodulation reference signal (DMRS) transmitted by the base station is obtained in the selected OFDM symbol.

Embodiments of the present disclosure also provide a non-transitory computer readable storage medium storing computer readable instructions executable by a processor, the computer readable instructions being executed by a processor The processor performs the following operations:

Embodiments of the present disclosure have the following beneficial effects:

In the foregoing technical solution of the embodiment of the present disclosure, in each short transmission time interval TTI, at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS is selected; and the demodulation reference signal is mapped in the selected OFDM symbol. DMRS. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure can ensure that each TTI includes DMRS, thereby greatly improving channel estimation performance.

DRAWINGS

1 is a working flowchart of a resource mapping method for demodulating a reference signal according to an embodiment of the present disclosure;

2 is still another working flowchart of a resource mapping method for demodulating a reference signal according to an embodiment of the present disclosure;

FIG. 3 is still another working flowchart of a resource mapping method for demodulating a reference signal according to an embodiment of the present disclosure;

4a is a first pilot pattern of a TTI of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

4b is a second pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

4c is a third pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

5a is a fourth pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

5b is a fifth pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmissions in an embodiment of the present disclosure;

5c is a sixth pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmissions in an embodiment of the present disclosure;

6a is a seventh pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

6b is an eighth pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

6c is a ninth pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmissions in an embodiment of the present disclosure;

7a is a tenth pilot pattern of a TTI of two OFDM symbol lengths supporting up to four layers of transmissions in an embodiment of the present disclosure;

7b is an eleventh pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

7c is a twelfth pilot pattern of TTIs of two OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

8a is a TTI of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure First pilot pattern;

8b is a second pilot pattern of a TTI of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

8c is a third pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

9a is a fourth pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

9b is a fifth pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

9c is a sixth pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmissions in an embodiment of the present disclosure;

10a is a seventh pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

10b is an eighth pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

10c is a ninth pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

11a is a tenth pilot pattern of a TTI of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

11b is an eleventh pilot pattern of a TTI of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

11c is a twelfth pilot pattern of TTIs of two OFDM symbol lengths supporting up to eight layers of transmission in an embodiment of the present disclosure;

12 is a pilot pattern of a TTI of seven OFDM symbol lengths supporting up to four layers of transmission in an embodiment of the present disclosure;

13 is a pilot pattern of a TTI of up to seven OFDM symbol lengths supporting eight layers of transmission in an embodiment of the present disclosure.

FIG. 14 is a structural block diagram of a base station according to an embodiment of the present disclosure;

FIG. 15 is a structural block diagram of a terminal according to an embodiment of the present disclosure;

16 is a block diagram showing another structure of a base station according to an embodiment of the present disclosure;

FIG. 17 is still another structural block diagram of a terminal according to an embodiment of the present disclosure.

detailed description

In order to make the technical problems, technical solutions and advantages of the present disclosure more clear, the following detailed description will be made in conjunction with the specific embodiments and the accompanying drawings.

An embodiment of the present disclosure provides a resource mapping method and a base station for demodulating a reference signal, which solves the problem that when the TTI length is shortened, the original pilot mapping manner cannot include DMRS in each TTI, thereby affecting channel estimation performance. The problem.

As shown in FIG. 1 , a resource mapping method for demodulating a reference signal according to an embodiment of the present disclosure includes:

Step 101: In each short transmission time interval TTI, select at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS.

In a specific embodiment of the present disclosure, at least one unmapped CRS OFDM symbol may be selected in each short TTI of a resource block including 14 OFDM symbols, and each OFDM symbol includes 12 subcarriers. The length of the short TTI is the length of time corresponding to the preset number of OFDM symbols, and the preset number is less than 14. Specifically, the length of the short TTI may be a length of time corresponding to two OFDM symbols or a length of time corresponding to seven OFDM symbols.

Step 102: Map the demodulation reference signal DMRS in the selected OFDM symbol.

Specifically, the demodulation reference signal DMRS is mapped in the selected OFDM symbol by using the CDM-F, where the CDM-F refers to spreading in the frequency domain by using Code Division Multiplexing (CDM). The embodiment of the present disclosure effectively avoids the DMRS and the common pilot occupying the same resource unit and the same by selecting the OFDM symbol of the unmapped common pilot CRS and using the CDM-F to map the demodulation reference signal DMRS in the selected OFDM symbol. OFDM symbols, and can guarantee that DMRS is included in each TTI.

In the resource mapping method of the demodulation reference signal of the embodiment of the present disclosure, in each short transmission time interval TTI, at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS is selected; in the selected OFDM symbol The demodulation reference signal DMRS is mapped. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure ensures that each TTI includes DMRS, which improves channel estimation performance.

As shown in FIG. 2, the resource mapping method of the demodulation reference signal in the embodiment of the present disclosure includes:

Step 201: If the length of the short TTI is the length of time corresponding to the two OFDM symbols, then in each of the short TTIs, one OFDM symbol of the unmapped CRS is selected.

In a specific embodiment of the present disclosure, one unmapped CRS OFDM symbol may be selected in each short TTI of a resource block including 14 OFDM symbols, and each OFDM symbol includes 12 subcarriers. For the case where the TTI is reduced to 2 OFDM symbols, if the control region of the resource block includes two OFDM symbols, and the CRS is mapped in both OFDM symbols in the control region, the first and last TTIs in the data region are available. Selecting one of the two OFDM symbols, selecting one OFDM symbol of the unmapped CRS in the TTI between the first TTI and the last TTI of the data region (the TTI between the first TTI and the last TTI of the data region) One of the two OFDM symbols has a mapped CRS).

Specifically, as shown in FIG. 4a, 4b, 4c, 8a, 8b, and 8c, if each subframe includes 14 OFDM symbols, a third OFDM symbol and a thirteenth OFDM are selected in each of the subframes. Symbol; or

As shown in FIGS. 6a, 6b, 6c, 10a, 10b, and 10c, a third OFDM symbol and a fourteenth OFDM symbol are selected in each of the subframes; or

As shown in FIGS. 5a, 5b, 5c, 9a, 9b, and 9c, a fourth OFDM symbol and a thirteenth OFDM symbol are selected in each of the subframes; or

As shown in FIGS. 7a, 7b, 7c, 11a, 11b, and 11c, a fourth OFDM symbol and a fourteenth OFDM symbol are selected in each of the subframes; or

Selecting a thirteenth OFDM symbol in each of the subframes (here, the case where the third OFDM symbol and the fourth OFDM symbol of each subframe are in the control region are not shown in the figure); or

A fourteenth OFDM symbol is selected in each of the subframes (here, the case where the third OFDM symbol and the fourth OFDM symbol of each subframe are in the control region, not shown in the figure).

Step 202: Map the demodulation reference signal DMRS in the selected OFDM symbol.

For the short TTI of 2 OFDM symbol lengths, when the number of antenna ports of the DMRS is at most 4 (based on the transmission with the highest supported layer number of 4), three pilot patterns for the antenna ports R7-R10 are proposed. Programmes (a), (b) and (c). For each TTI, the frequency domain is a column of 4 The reference signals on the REs are subjected to CDM multiplexing processing for frequency domain spreading, and the orthogonality between the pilot ports is ensured by frequency domain extension. Wherein, (a) the scheme is as shown in FIG. 4a, 5a, 6a, and 7a, and a column of DMRS is inserted on each TTI, occupying the resource element RE position of k=1, 2, 7, and 8 in the frequency domain, and avoiding the CRS symbol. Conflict, (b) scheme shown in Figures 4b, 5b, 6b, and 7b, on the basis of (a) scheme, let DMRS be evenly distributed in the physical resource block PRB as much as possible, (c) as shown in Figures 4c and 5c. As shown in 6c and 7c, the DMRS is distributed as much as possible on the edge of the PRB on the basis of the (a) scheme.

Specifically, as shown in FIG. 4a, 5a, 6a, and 7a, the number of antenna ports of the DMRS is at most 4, and if one resource block RB or 12 subcarriers are used as a unit in the frequency domain, each of the selected ones Mapping the DMRS in the second subcarrier, the third subcarrier, the eighth subcarrier, and the ninth subcarrier in the OFDM symbol; or

As shown in FIG. 4b, 5b, 6b, and 7b, mapping the DMRS in the second subcarrier, the fifth subcarrier, the eighth subcarrier, and the twelfth subcarrier in each selected OFDM symbol; or

As shown in FIGS. 4c, 5c, 6c, and 7c, the DMRS is mapped in the first subcarrier, the second subcarrier, the ninth subcarrier, and the tenth subcarrier in each selected OFDM symbol.

In the embodiment of the present disclosure, for a short TTI of 2 OFDM symbol lengths, and the number of antenna ports of the DMRS is at most 8 (based on a transmission with a maximum supported layer number of 8), three pilot pattern schemes are proposed. For each TTI, antenna ports R7, R8, R11, and R13 are a group of CDM groups, and antenna ports R9, R10, R12, and R14 are another group of CDM groups, and different CDM groups are distinguished by frequency division.

Specifically, as shown in FIG. 8a, 9a, 10a, and 11a, the number of antenna ports of the DMRS is at most 8. If one RB or 12 subcarriers are used as a unit in the frequency domain, then each selected OFDM is selected. Mapping the DMRS in the second subcarrier, the third subcarrier, the fourth subcarrier, the fifth subcarrier, the eighth subcarrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier in the symbol; or

As shown in FIG. 8b, 9b, 10b, and 11b, the first subcarrier, the second subcarrier, the fourth subcarrier, the fifth subcarrier, the seventh subcarrier, and the eighth subcarrier in each selected OFDM symbol Mapping the DMRS in the carrier, the 11th subcarrier, and the 12th subcarrier; or

As shown in FIGS. 8c, 9c, 10c, and 11c, the first subcarrier, the second subcarrier, the third subcarrier, the fourth subcarrier, the ninth subcarrier, and the tenth in each selected OFDM symbol The DMRS is mapped in the subcarriers, the 11th subcarrier, and the 12th subcarrier.

A resource mapping method for demodulating reference signals according to an embodiment of the present disclosure, for each short transmission time interval TTI, for each short transmission time interval TTI, an orthogonal frequency division multiplexing OFDM with unmapped common pilot CRS is selected. Symbol; mapping the demodulation reference signal DMRS in the selected OFDM symbol. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure ensures that each TTI includes DMRS, which improves channel estimation performance.

As shown in FIG. 3, the resource mapping method of the demodulation reference signal in the embodiment of the present disclosure includes:

Step 301: If the length of the short TTI is the length of time corresponding to the seven OFDM symbols, select at least one orthogonal frequency division multiplexing with unmapped common pilot CRS according to the maximum number of antenna ports of the DMRS. OFDM symbol.

In a specific embodiment of the present disclosure, at least one unmapped CRS OFDM symbol may be selected in each short TTI of a resource block including 14 OFDM symbols, and each OFDM symbol includes 12 subcarriers. For the short TTI of 7 OFDM symbol lengths in the disclosed embodiment, the pilot resource mapping can also be performed using the CDM-F method. For each TTI, two or four columns of pilots can be inserted, all belonging to the same CDM group. Under the premise of not cooperating with the CRS symbol, the position of the pilot in the frequency domain is distributed on 4 REs, wherein the two REs are divided into two groups, and the two groups of REs are separated by a certain distance; The column pilots are also separated by a certain distance. Figures 12 and 13 are two pilot patterns that support up to 4 layers of transmission and up to 8 layers of transmission, respectively. Figure 12 shows the pilot pattern of the antenna ports R7-R10 based on the maximum supported 4-layer transmission. The pilot occupied positions in the frequency domain are k = 1, 2, 7, and 8, and the occupied position in the time domain is 1 = 2,5; Figure 13 shows the pilot pattern of the antenna port R7-R14 based on the maximum support of 8 layers of transmission, the pilot occupied position in the frequency domain is k = 1, 2, 7, 8, occupied in the time domain The position is 1=2, 3, 5, 6.

For the case where the TTI is reduced to 7 OFDM symbols, at least one or at least two OFDM symbols may be selected according to the maximum number of antenna ports of the DMRS.

Specifically, if the number of antenna ports of the DMRS is at most 4, at least one OFDM symbol that does not map the common pilot CRS is selected in each short TTI. Further, as shown in FIG. 12, in each short TTI, a third OFDM symbol and a sixth OFDM symbol are selected; or

In each short TTI, the 4th OFDM symbol and the 6th OFDM symbol are selected; or

In each short TTI, the 3rd OFDM symbol and the 7th OFDM symbol are selected; or

In each short TTI, the 4th OFDM symbol and the 7th OFDM symbol are selected; or

In each short TTI, the 6th OFDM symbol is selected (here, the case where the third OFDM symbol and the fourth OFDM symbol of each subframe are in the control region are not shown in the figure); or

In each short TTI, the 7th OFDM symbol is selected (here, the case where the third OFDM symbol and the fourth OFDM symbol of each subframe are in the control region, not shown in the figure).

If the number of antenna ports of the DMRS is at most 8, in each short TTI, at least two OFDM symbols not mapped to the common pilot CRS are selected. Further, as shown in FIG. 13, in each short TTI, a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol are selected; or

In each short TTI, the 6th OFDM symbol and the 7th OFDM symbol are selected (here, the case where the third OFDM symbol and the fourth OFDM symbol of each subframe are in the control region are not shown in the figure).

Step 302: Map the demodulation reference signal DMRS in the selected OFDM symbol.

Specifically, as shown in FIG. 12 and FIG. 13 , if one RB or 12 subcarriers are used as a unit in the frequency domain, two or four adjacent subcarrier mapping demodulation references are selected in each selected OFDM symbol. A signal DMRS, wherein each of the selected subcarriers occupies the same frequency domain position in different OFDM symbols.

Further, as shown in FIGS. 12 and 13, the second subcarrier, the third word carrier, the eighth word subcarrier, and the ninth subcarrier mapping demodulation reference signal DMRS are selected in each selected OFDM symbol.

A resource mapping method for demodulating reference signals according to an embodiment of the present disclosure, for each short transmission time interval TTI, selecting a plurality of orthogonal frequency division multiplexing of unmapped common pilot CRSs for a short TTI of 7 OFDM symbol lengths OFDM symbol; the demodulation reference signal DMRS is mapped in the selected OFDM symbol. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure ensures that each TTI includes DMRS, which improves channel estimation performance.

As shown in FIG. 14, an embodiment of the present disclosure further provides a base station, including:

The first selecting module 141 is configured to select, in each short transmission time interval TTI, at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS;

The mapping module 142 is configured to map the demodulation reference signal DMRS in the selected OFDM symbol, And sending the DMRS.

In the base station of the embodiment of the present disclosure, the first selection module 141 includes:

The first selection sub-module 1411 is configured to select, in each of the short TTIs, an OFDM symbol that is not mapped to the CRS, if the length of the short TTI is a length of time corresponding to two OFDM symbols.

In the base station of the embodiment of the present disclosure, the first selecting sub-module 1411 is configured to: when each subframe includes 14 OFDM symbols, select a third OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.

The base station of the embodiment of the present disclosure, the mapping module 142 includes:

The first mapping sub-module 1421, the number of antenna ports for the DMRS is up to 4, and one resource block RB or 12 sub-carriers are one unit in the frequency domain, and then the first in each selected OFDM symbol Mapping DMRS in 2 subcarriers, 3rd subcarrier, 8th subcarrier, and 9th subcarrier; or

a second mapping sub-module 1422, where the number of antenna ports for the DMRS is at most 8 and one RB or 12 sub-carriers are used as a unit in the frequency domain, and then the second sub-input of each selected OFDM symbol Carrier, 3rd subcarrier, 4th subcarrier, 5th subcarrier, 8th Mapping DMRS in subcarrier, ninth subcarrier, tenth subcarrier, and eleventh subcarrier; or

a second selection sub-module 1412, configured to select at least one unmapped common pilot CRS according to a maximum value of the number of antenna ports of the DMRS, if the length of the short TTI is a length of time corresponding to seven OFDM symbols Orthogonal Frequency Division Multiplexing (OFDM) symbols.

The base station of the embodiment of the present disclosure, the second selection sub-module 1412 includes:

The first selecting unit 14121 is configured to: if each of the short TTIs selects at least one OFDM symbol that does not map the common pilot CRS, if the number of antenna ports of the DMRS is at most 4.

In the base station of the embodiment of the present disclosure, the first selecting unit is configured to select a third OFDM symbol and a sixth OFDM symbol in each short TTI; or

In each short TTI, the 4th OFDM symbol and the 6th OFDM symbol are selected; or

In each short TTI, the 3rd OFDM symbol and the 7th OFDM symbol are selected; or

In each short TTI, the 4th OFDM symbol and the 7th OFDM symbol are selected; or

In each short TTI, the sixth OFDM symbol is selected; or

In each short TTI, the 7th OFDM symbol is selected.

The second selecting unit 14122 is configured to select at least two OFDM symbols that do not map the common pilot CRS in each short TTI if the number of antenna ports of the DMRS is at most 8.

In the base station of the embodiment of the present disclosure, the second selecting unit is configured to select, in each short TTI, a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol; or

In each short TTI, the 6th OFDM symbol and the 7th OFDM symbol are selected.

The third mapping sub-module 1423 is configured to: if there are 1 RB or 12 sub-carriers as a unit in the frequency domain, select two adjacent two sub-carrier mapping demodulation reference signals DMRS in each selected OFDM symbol. Wherein each of the selected subcarriers occupies the same frequency domain position in different OFDM symbols.

In the base station of the embodiment of the present disclosure, the third mapping sub-module 1423 is configured to select a second subcarrier, a third word carrier, an eighth subcarrier, and a ninth subcarrier mapping demodulation in each selected OFDM symbol. Reference signal DMRS.

It should be noted that the base station is a base station corresponding to the foregoing method embodiment. All the implementation manners in the foregoing method embodiments are applicable to the embodiment of the base station, and the same technical effects can be achieved.

The base station according to the embodiment of the present disclosure selects at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS in each short transmission time interval TTI; and maps the demodulation reference signal DMRS in the selected OFDM symbol. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure can ensure that each TTI includes DMRS, thereby greatly improving channel estimation performance.

An embodiment of the present disclosure further provides a terminal, as shown in FIG. 15, including:

The second selecting module 151 is configured to select, in each short transmission time interval TTI, at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS;

The obtaining module 152 is configured to obtain, in the selected OFDM symbol, a demodulation reference signal DMRS sent by the base station.

The terminal of the embodiment of the present disclosure, the second selection module 151 includes:

The third selection sub-module 1511 is configured to select, in each of the short TTIs, an OFDM symbol that is not mapped to the CRS, if the length of the short TTI is a length of time corresponding to two OFDM symbols.

In the terminal of the embodiment of the present disclosure, the third selecting sub-module 1511 is configured to: when each subframe includes 14 OFDM symbols, select a third OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or By

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.

The terminal of the embodiment of the present disclosure, the obtaining module 152 includes:

a first obtaining sub-module 1521, where the number of antenna ports used in the DMRS is at most 4 and 1 resource block RB or 12 sub-carriers in a frequency domain is a unit, and then in each selected OFDM symbol Acquiring the DMRS sent by the base station in the 2 subcarriers, the 3rd subcarrier, the 8th subcarrier, and the ninth subcarrier; or

a second obtaining sub-module 1522, wherein the number of antenna ports for the DMRS is at most 8 and one RB or 12 subcarriers are used as a unit in the frequency domain, and then the second sub-input of each selected OFDM symbol Acquiring the DMRS sent by the base station in the carrier, the third subcarrier, the fourth subcarrier, the fifth subcarrier, the eighth subcarrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier; or

The fourth selection sub-module 1512 is configured to select at least one of the maximum length of the number of antenna ports of the DMRS if the length of the short TTI is the length of time corresponding to the seven OFDM symbols. Orthogonal Frequency Division Multiplexing OFDM symbols that do not map the common pilot CRS.

The terminal of the embodiment of the present disclosure, the fourth selection sub-module 1512 includes:

The third selecting unit 15121 is configured to: if each of the short TTIs selects at least one OFDM symbol that does not map the common pilot CRS, if the number of antenna ports of the DMRS is at most 4.

In the terminal of the embodiment of the present disclosure, the third selecting unit 15121 is configured to select a third OFDM symbol and a sixth OFDM symbol in each short TTI; or

In each short TTI, the 4th OFDM symbol and the 6th OFDM symbol are selected; or

In each short TTI, the 3rd OFDM symbol and the 7th OFDM symbol are selected; or

In each short TTI, the 4th OFDM symbol and the 7th OFDM symbol are selected; or

In each short TTI, the sixth OFDM symbol is selected; or

In each short TTI, the 7th OFDM symbol is selected.

The fourth selecting unit 15122 is configured to: if each of the short TTIs selects at least two OFDM symbols that do not map the common pilot CRS, if the number of antenna ports of the DMRS is at most 8.

In the base station of the embodiment of the present disclosure, the fourth selecting unit is configured to select, in each short TTI, a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol; or

In each short TTI, the 6th OFDM symbol and the 7th OFDM symbol are selected.

The third obtaining sub-module 1523 is configured to: if one RB or 12 sub-carriers are used as one unit in the frequency domain, select two adjacent four sub-carriers in each selected OFDM symbol to obtain demodulation sent by the base station. The reference signal DMRS, wherein each of the selected subcarriers occupies the same frequency domain position in different OFDM symbols.

In the terminal of the embodiment of the present disclosure, the third obtaining sub-module 1523 is configured to select a second subcarrier, a third word carrier, an eighth subcarrier, and a ninth subcarrier to obtain a base station to send in each selected OFDM symbol. Demodulation reference signal DMRS.

It should be noted that the terminal is a terminal corresponding to the foregoing method embodiment. All the implementation manners in the foregoing method embodiments are applicable to the embodiment of the terminal, and the same technical effects can be achieved.

The terminal of the embodiment of the present disclosure selects at least one not in each short transmission time interval TTI. And mapping orthogonal OFDM OFDM symbols of the common pilot CRS; acquiring a demodulation reference signal DMRS sent by the base station in the selected OFDM symbol. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure can ensure that each TTI includes DMRS, thereby greatly improving channel estimation performance.

In order to better achieve the above object, as shown in FIG. 16, an embodiment of the present disclosure further provides a base station, where the base station includes: a processor 1600; a memory 1620 connected to the processor 1600 through a bus interface, and a transceiver 1610 coupled to the processor 1600 via a bus interface; the memory 1620 for storing programs and data used by the processor in performing operations; transmitting data information or pilots through the transceiver 1610, The uplink control channel is received by the transceiver 1610; when the processor 1600 calls and executes the program and data stored in the memory 1620, the following functional modules are implemented:

And a mapping module, configured to map the demodulation reference signal DMRS in the selected OFDM symbol, and send the DMRS.

The processor 1600 is configured to read the program in the memory 1620, and perform the following process: in each short transmission time interval TTI, select at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS, in the selected The demodulation reference signal DMRS is mapped in the OFDM symbol and transmitted by the transceiver 1610.

The transceiver 1610 is configured to receive and transmit data under the control of the processor 1600.

In FIG. 16, the bus architecture may include any number of interconnected buses and bridges, specifically linked by one or more processors represented by processor 1600 and various circuits of memory represented by memory 1620. The bus architecture can also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and, therefore, will not be further described herein. The bus interface provides an interface. The transceiver 1610 can be a plurality of components, including a transmitter and a transceiver, providing means for communicating with various other devices on a transmission medium. The processor 1600 is responsible for managing the bus architecture and general processing, and the memory 1620 can store data used by the processor 1600 in performing operations.

The base station of the embodiment of the present disclosure, the processor 1600 is configured to use, in each short transmission time interval TTI, And selecting at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS; mapping the demodulation reference signal DMRS in the selected OFDM symbol. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure can ensure that each TTI includes DMRS, thereby greatly improving channel estimation performance.

In order to achieve the above objective, as shown in FIG. 17, an embodiment of the present disclosure further provides a terminal, where the terminal includes: a processor 1700; a memory 1720 connected to the processor 1700 through a bus interface, and a transceiver 1710 coupled to the processor 1700; the memory for storing programs and data used by the processor in performing operations; receiving, by the transceiver 1710, a downlink control channel; when the processor 1700 is invoked When the program and data stored in the memory 1720 are executed, the following functional modules are implemented:

The processor 1700 is configured to read a program in the memory 1720, and perform the following process: in each short transmission time interval TTI, select at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS, and pass the transceiver. 1710: Obtain a demodulation reference signal DMRS sent by the base station in the selected OFDM symbol.

The transceiver 1710 is configured to receive and transmit data under the control of the processor 1700.

Here, in FIG. 17, the bus architecture may include any number of interconnected buses and bridges, specifically linked by one or more processors represented by processor 1700 and various circuits of memory represented by memory 1520. The bus architecture can also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and, therefore, will not be further described herein. The bus interface provides an interface. Transceiver 1710 can be a plurality of components, including a transmitter and a receiver, providing means for communicating with various other devices on a transmission medium. For different user equipments, the user interface 1730 may also be an interface capable of externally connecting the required devices, including but not limited to a keypad, a display, a speaker, a microphone, a joystick, and the like.

The processor 1700 is responsible for managing the bus architecture and general processing, and the memory 1720 can store data used by the processor 1700 in performing operations.

In the terminal of the embodiment of the present disclosure, the processor 1700 is configured to: in each short transmission time interval TTI, select at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS; acquire the base station in the selected OFDM symbol. The demodulation reference signal DMRS is transmitted. When performing resource mapping of the demodulation reference signal, the embodiment of the present disclosure can ensure that each TTI includes DMRS, thereby greatly improving channel estimation performance.

The above description is only for the optional embodiments of the present disclosure, and is not intended to limit the disclosure. Any modifications, equivalents, improvements, etc., which are within the scope of the present disclosure, should be included in the scope of the present disclosure. within.

Claims

A resource mapping method for demodulating a reference signal, comprising:

In each short transmission time interval (TTI), at least one orthogonal frequency division multiplexing (OFDM) symbol that does not map a common pilot (CRS) is selected;

A demodulation reference signal (DMRS) is mapped in the selected OFDM symbol.
The resource mapping method of demodulation reference signals according to claim 1, wherein said orthogonal frequency division multiplexing of at least one unmapped common pilot (CRS) is selected in each short transmission time interval (TTI) The steps of the (OFDM) symbol include:

If the length of the short TTI is the length of time corresponding to two OFDM symbols, in each of the short TTIs, one OFDM symbol of the unmapped CRS is selected.
The method for resource mapping of a demodulation reference signal according to claim 2, wherein if the length of the short TTI is a length of time corresponding to two OFDM symbols, in each of the short TTIs, A step of not mapping CRS OFDM symbols includes:

If each subframe includes 14 OFDM symbols, selecting a third OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a third OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.
The resource mapping method for demodulating reference signals according to claim 2, wherein the number of antenna ports of the DMRS is at most 4;

The step of mapping the demodulation reference signal DMRS in the selected OFDM symbol includes:

If one resource block (RB) or 12 subcarriers is used as a unit in the frequency domain, the second subcarrier, the third subcarrier, the eighth subcarrier, and the ninth in each selected OFDM symbol Mapping DMRS in subcarriers; or

Mapping the DMRS in the second subcarrier, the fifth subcarrier, the eighth subcarrier, and the twelfth subcarrier in each selected OFDM symbol; or

The DMRS is mapped in the first subcarrier, the second subcarrier, the ninth subcarrier, and the tenth subcarrier in each selected OFDM symbol.
The resource mapping method for demodulating reference signals according to claim 2, wherein the number of antenna ports of the DMRS is at most 8;

The step of mapping the demodulation reference signal DMRS in the selected OFDM symbol includes:

If one RB or 12 subcarriers are used as a unit in the frequency domain, the second subcarrier, the third subcarrier, the fourth subcarrier, the fifth subcarrier, and the eighth subcarrier in each selected OFDM symbol Mapping the DMRS in the carrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier; or

In the first subcarrier, the second subcarrier, the fourth subcarrier, the fifth subcarrier, the seventh subcarrier, the eighth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Map DMRS; or

In the first subcarrier, the second subcarrier, the third subcarrier, the fourth subcarrier, the ninth subcarrier, the tenth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Map DMRS.
The resource mapping method of demodulation reference signals according to claim 1, wherein said orthogonal frequency division multiplexing of at least one unmapped common pilot (CRS) is selected in each short transmission time interval (TTI) The steps of the (OFDM) symbol include:

If the length of the short TTI is the length of time corresponding to the seven OFDM symbols, at least one orthogonal frequency division multiplexing OFDM symbol that does not map the common pilot CRS is selected according to the maximum value of the number of antenna ports of the DMRS.
The resource mapping method for demodulating reference signals according to claim 6, wherein if the length of the short TTI is a length of time corresponding to seven OFDM symbols, the maximum number of antenna ports according to the DMRS is used. The step of selecting at least one Orthogonal Frequency Division Multiplexing (OFDM) symbol that does not map the Common Pilot (CRS) includes:

If the number of antenna ports of the DMRS is at most 4, in each of the short TTIs, One less OFDM symbol that does not map the common pilot CRS.
The resource mapping method for demodulating reference signals according to claim 7, wherein if the number of antenna ports of the DMRS is at most 4, at least one unmapped common pilot is selected in each of the short TTIs ( The steps of the OFDM symbol of CRS) include:

In each of the short TTIs, selecting a third OFDM symbol and a sixth OFDM symbol; or

In each of the short TTIs, selecting a fourth OFDM symbol and a sixth OFDM symbol; or

In each of the short TTIs, selecting a third OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, selecting a fourth OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol is selected; or

In each of the short TTIs, the 7th OFDM symbol is selected.
The resource mapping method for demodulating reference signals according to claim 6, wherein if the length of the short TTI is a length of time corresponding to seven OFDM symbols, the maximum number of antenna ports according to the DMRS is used. The step of selecting at least one Orthogonal Frequency Division Multiplexing (OFDM) symbol that does not map the Common Pilot (CRS) includes:

If the number of antenna ports of the DMRS is at most 8, in each of the short TTIs, at least two OFDM symbols of unmapped CRS are selected.
The resource mapping method for demodulating reference signals according to claim 9, wherein if the number of antenna ports of the DMRS is at most 8, at least two unmapped common pilots are selected in each of the short TTIs. The steps of the (CRS) OFDM symbol include:

In each of the short TTIs, selecting a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol and a seventh OFDM symbol are selected.
The resource mapping method for demodulating a reference signal according to claim 7 or 9, wherein the step of mapping a demodulation reference signal (DMRS) in the selected OFDM symbol comprises:

If one RB or 12 subcarriers are used as a unit in the frequency domain, then each selected OFDM is selected. The symbol selects two adjacent two subcarrier mapping DMRSs, wherein each selected subcarrier occupies the same frequency domain position in different OFDM symbols.
The resource mapping method for demodulating reference signals according to claim 11, wherein the step of selecting two adjacent two subcarrier mapping DMRSs in each selected OFDM symbol comprises:

The second subcarrier, the third word carrier, the eighth subcarrier, and the ninth subcarrier mapping DMRS are selected in each selected OFDM symbol.
A base station comprising:

a first selecting module, configured to select at least one Orthogonal Frequency Division Multiplexing (OFDM) symbol that does not map a common pilot (CRS) in each short transmission time interval (TTI);

And a mapping module, configured to map a demodulation reference signal (DMRS) in the selected OFDM symbol, and send the DMRS.
The base station according to claim 13, wherein the first selection module comprises:

And a first selecting submodule, configured to select, in each of the short TTIs, an OFDM symbol that is not mapped to the CRS, if the length of the short TTI is a length of time corresponding to two OFDM symbols.
The base station according to claim 14, wherein the first selection submodule is configured to select a third OFDM symbol and a thirteenth in each of the subframes if each subframe includes 14 OFDM symbols OFDM symbol; or

Selecting a third OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.
The base station according to claim 14, wherein the mapping module comprises:

a first mapping submodule, where the number of antenna ports for the DMRS is up to 4 and in the frequency domain Mapping the DMRS in the second subcarrier, the third subcarrier, the eighth subcarrier, and the ninth subcarrier in each selected OFDM symbol by using one resource block RB or 12 subcarriers as one unit; or

Mapping the DMRS in the second subcarrier, the fifth subcarrier, the eighth subcarrier, and the twelfth subcarrier in each selected OFDM symbol; or

The DMRS is mapped in the first subcarrier, the second subcarrier, the ninth subcarrier, and the tenth subcarrier in each selected OFDM symbol.
The base station according to claim 14, wherein the mapping module comprises:

a second mapping submodule, where the number of antenna ports for the DMRS is at most 8 and one RB or 12 subcarriers are used as a unit in the frequency domain, and then the second subcarrier in each selected OFDM symbol Mapping the DMRS in the third subcarrier, the fourth subcarrier, the fifth subcarrier, the eighth subcarrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier; or

In the first subcarrier, the second subcarrier, the fourth subcarrier, the fifth subcarrier, the seventh subcarrier, the eighth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Map DMRS; or

In the first subcarrier, the second subcarrier, the third subcarrier, the fourth subcarrier, the ninth subcarrier, the tenth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Map DMRS.
The base station according to claim 13, wherein the first selection module comprises:

And a second selection submodule, configured to select at least one OFDM symbol of the unmapped CRS according to a maximum value of the number of antenna ports of the DMRS, if the length of the short TTI is a length of time corresponding to the seven OFDM symbols.
The base station according to claim 18, wherein the second selection submodule comprises:

The first selecting unit is configured to: if each of the short TTIs selects at least one OFDM symbol that is not mapped to the CRS, if the number of antenna ports of the DMRS is at most 4.
The base station according to claim 19, wherein the first selecting unit is configured to select a third OFDM symbol and a sixth OFDM symbol in each of the short TTIs; or

In each of the short TTIs, selecting a fourth OFDM symbol and a sixth OFDM symbol; or

In each of the short TTIs, selecting a third OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, selecting a fourth OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol is selected; or

In each of the short TTIs, the 7th OFDM symbol is selected.
The base station according to claim 18, wherein the second selection submodule comprises:

And a second selecting unit, configured to: if each of the short TTIs selects at least two OFDM symbols that are not mapped to the CRS, if the number of antenna ports of the DMRS is at most 8.
The base station according to claim 21, wherein the second selecting unit is configured to select, in each of the short TTIs, a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol. ;or

In each of the short TTIs, a sixth OFDM symbol and a seventh OFDM symbol are selected.
The base station according to claim 19 or 21, wherein the mapping module comprises:

a third mapping submodule, configured to select one or two adjacent four subcarrier mapping DMRSs in each selected OFDM symbol if one RB or 12 subcarriers are used as a unit in the frequency domain, where selected Each subcarrier occupies the same frequency domain position in different OFDM symbols.
The base station according to claim 23, wherein the third mapping submodule is configured to select a second subcarrier, a third word carrier, an 8th subcarrier, and a ninth subcarrier in each selected OFDM symbol. Map DMRS.
A terminal comprising:

a second selecting module, configured to select at least one Orthogonal Frequency Division Multiplexing (OFDM) symbol that does not map a common pilot (CRS) in each short transmission time interval (TTI);

And an obtaining module, configured to obtain, in the selected OFDM symbol, a demodulation reference signal (DMRS) sent by the base station.
The terminal of claim 25, wherein the second selection module comprises:

And a third selection submodule, configured to select, in each of the short TTIs, an OFDM symbol that is not mapped to the CRS, if the length of the short TTI is a length of time corresponding to two OFDM symbols.
The terminal according to claim 26, wherein the third selecting submodule is configured to select a third OFDM symbol and a thirteenth in each of the subframes if each subframe includes 14 OFDM symbols OFDM symbol; or

Selecting a third OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a thirteenth OFDM symbol in each of the subframes; or

Selecting a fourth OFDM symbol and a fourteenth OFDM symbol in each of the subframes; or

Selecting a thirteenth OFDM symbol in each of the subframes; or

A fourteenth OFDM symbol is selected in each of the subframes.
The terminal of claim 26, wherein the obtaining module comprises:

a first obtaining submodule, where the number of antenna ports for the DMRS is at most 4 and 1 resource block RB or 12 subcarriers are used as a unit in the frequency domain, and then 2nd in each selected OFDM symbol Acquiring the DMRS sent by the base station in the subcarrier, the third subcarrier, the 8th subcarrier, and the ninth subcarrier; or

Acquiring the DMRS sent by the base station in the second subcarrier, the fifth subcarrier, the eighth subcarrier, and the twelfth subcarrier in each selected OFDM symbol; or

The DMRS sent by the base station is obtained in the first subcarrier, the second subcarrier, the ninth subcarrier, and the tenth subcarrier in each selected OFDM symbol.
The terminal of claim 26, wherein the obtaining module comprises:

a second obtaining submodule, where the number of antenna ports for the DMRS is at most 8 and 1 RB or 12 subcarriers are used as a unit in the frequency domain, and then the second subcarrier in each selected OFDM symbol Obtaining, by the third subcarrier, the fourth subcarrier, the fifth subcarrier, the eighth subcarrier, the ninth subcarrier, the tenth subcarrier, and the eleventh subcarrier, a DMRS sent by the base station; or

In the first subcarrier, the second subcarrier, the fourth subcarrier, the fifth subcarrier, the seventh subcarrier, the eighth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Obtaining the DMRS sent by the base station; or

In the first subcarrier, the second subcarrier, the third subcarrier, the fourth subcarrier, the ninth subcarrier, the tenth subcarrier, the eleventh subcarrier, and the twelfth subcarrier in each selected OFDM symbol Obtain the DMRS sent by the base station.
The terminal of claim 25, wherein the second selection module comprises:

And a fourth selecting submodule, configured to select at least one OFDM symbol of the unmapped CRS according to a maximum value of the number of antenna ports of the DMRS, if the length of the short TTI is a length of time corresponding to the seven OFDM symbols.
The terminal according to claim 30, wherein the fourth selection submodule comprises:

And a third selecting unit, configured to: if each of the short TTIs selects at least one OFDM symbol that is not mapped to the CRS, if the number of antenna ports of the DMRS is at most 4.
The terminal according to claim 31, wherein the third selecting unit is configured to select a third OFDM symbol and a sixth OFDM symbol in each of the short TTIs; or

In each of the short TTIs, selecting a fourth OFDM symbol and a sixth OFDM symbol; or

In each of the short TTIs, selecting a third OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, selecting a fourth OFDM symbol and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol is selected; or

In each of the short TTIs, the 7th OFDM symbol is selected.
The terminal according to claim 30, wherein the fourth selection submodule comprises:

And a fourth selecting unit, configured to: if each of the short TTIs selects at least two OFDM symbols that are not mapped to the CRS, if the number of the antenna ports of the DMRS is at most 8.
The terminal according to claim 33, wherein the fourth selecting unit is configured to select, in each of the short TTIs, a third OFDM symbol, a fourth OFDM symbol, a sixth OFDM symbol, and a seventh OFDM symbol; or

In each of the short TTIs, a sixth OFDM symbol and a seventh OFDM symbol are selected.
The terminal according to claim 31 or 33, wherein the obtaining module comprises:

a third obtaining submodule, configured to use one RB or 12 subcarriers as a unit in the frequency domain, Then, the DMRSs sent by the base station are obtained by selecting two adjacent four subcarriers in each selected OFDM symbol, where each selected subcarrier occupies the same frequency domain position in different OFDM symbols.
The terminal according to claim 35, wherein the third obtaining submodule is configured to select a second subcarrier, a third word carrier, an 8th subcarrier, and a 9th subcarrier in each selected OFDM symbol. Obtain the DMRS sent by the base station.
A base station comprising:

Processor;

a transceiver for receiving and transmitting data under the control of the processor,

The processor is configured to do the following:

In each short transmission time interval (TTI), at least one orthogonal frequency division multiplexing (OFDM) symbol that does not map a common pilot (CRS) is selected;

A demodulation reference signal (DMRS) is mapped in the selected OFDM symbol and the DMRS is transmitted.
A terminal comprising:

Processor;

a transceiver for receiving and transmitting data under the control of the processor,

The processor is configured to do the following:

In each short transmission time interval (TTI), at least one orthogonal frequency division multiplexing (OFDM) symbol that does not map a common pilot (CRS) is selected;

A demodulation reference signal (DMRS) transmitted by the base station is obtained in the selected OFDM symbol.
A non-transitory computer readable storage medium storing computer readable instructions executable by a processor, the processor executing when the computer readable instructions are executed by a processor The following operations:

In each short transmission time interval (TTI), at least one orthogonal frequency division multiplexing (OFDM) symbol that does not map a common pilot (CRS) is selected;

A demodulation reference signal (DMRS) is mapped in the selected OFDM symbol and the DMRS is transmitted.
A non-transitory computer readable storage medium, the computer readable storage medium There are stored computer readable instructions executable by the processor, the processor performing the following operations when the computer readable instructions are executed by the processor:

In each short transmission time interval (TTI), at least one orthogonal frequency division multiplexing (OFDM) symbol that does not map a common pilot (CRS) is selected;

A demodulation reference signal (DMRS) transmitted by the base station is obtained in the selected OFDM symbol.