CN108347767B

CN108347767B - Method and device for receiving and transmitting demodulation reference signal

Info

Publication number: CN108347767B
Application number: CN201710053690.0A
Authority: CN
Inventors: 胡丽洁; 徐晓东; 侯雪颖; 夏亮
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2017-01-24
Filing date: 2017-01-24
Publication date: 2021-01-15
Anticipated expiration: 2037-01-24
Also published as: CN108347767A

Abstract

The invention provides a method and a device for receiving and transmitting demodulation reference signals. In the transceiving method, first scheduling information is sent to a terminal, wherein the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, the first DMRS pattern is one of a preset pattern set, the preset pattern set comprises a plurality of DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of a plurality of DMRS candidate positions in a preset time-frequency range; and determining the time domain and/or frequency domain position of DMRS transmission according to the first DMRS pattern, and transmitting or receiving the DMRS. The invention can realize the indication of the DMRS transmission position under the condition of sharing the DMRS, and can realize the indication of different numbers and densities of the time domain symbols of the DMRS.

Description

Method and device for receiving and transmitting demodulation reference signal

Technical Field

The present invention relates to a wireless interface physical layer of a mobile communication technology, and in particular, to a method and an apparatus for transmitting and receiving a demodulation reference signal.

Background

The Demodulation of the uplink Demodulation reference signal (DMRS), sometimes referred to as a cell discovery signal (DRS), is used for channel estimation for uplink correlation detection, and the Physical Uplink Shared Channel (PUSCH) and the Physical Uplink Control Channel (PUCCH) require the uplink reference signal for correlation Demodulation. In a related art Long Term Evolution (LTE) system, a DMRS for PUSCH demodulation is located at a 4 th single carrier frequency division multiple access (SC-FDMA) symbol of each uplink slot when a Normal cyclic prefix (Normal CP) is employed. In each subframe, there is transmission of a DMRS of two symbols, one for each slot, as shown in fig. 1, with 0-13 in fig. 1 representing one SC-FDMA symbol, respectively. For extended CP, DMRS is located on the 3 rd SC-FDMA symbol of each slot.

The downlink DMRSs are also used for channel estimation for downlink channel detection, but since the downlink is transmitted by using Orthogonal Frequency Division Multiplexing (OFDM), the downlink DMRSs may be discontinuous in time and frequency.

In the R13 and R14 versions of LTE, low latency design is performed, mainly discussing that the air interface latency is reduced by a shortened transmission time interval tti (sTTI) design, in R14, different sTTI lengths are defined, and for Frequency Division Duplex (FDD), downlink supports sTTI of 7OFDM symbols (OS, OFDM symbols) and 2 OS; uplink supports the sTTI of 7OS, 4OS and 2OS, which does not exclude the continuous reduction of the number of supportable sTTI; for Time Division Duplex (TDD), both uplink and downlink support the sTTI design of 7 OS.

For any sTTI length, DMRS design needs to be considered to demodulate traffic data. Because Resource Elements (REs) allowing transmission of the DMRS in downlink are discontinuous in time-frequency domain, the overhead of the downlink DMRS can be controlled; considering the orthogonal frequency division multiplexing multiple access (DFT-S-OFDM) with discrete fourier transform spread in the uplink of LTE, however, to maintain the single carrier characteristic, the DMRS needs to be continuous in the frequency domain, as shown in fig. 1, if the DMRS is transmitted in each sTTI, the overhead of the DMRS is increased, especially for the short sTTI, which is more serious, for example, for the sTTI of 2OS, if the DMRS occupies one OFDM symbol, the pilot overhead is 50%, which is not acceptable. Therefore, in the design of DMRS, DMRS sharing between different sTTI is supported for short sTTI lengths. One current scheme is that the sTTI of 7OS adopts the existing DMRS configuration, i.e. each sTTI has a column of DMRSs, the sTTI of 4OS is designed to use 7 symbols of one slot (slot) to divide into 2 sTTI of 4 symbols, and one shared symbol in the middle performs DMRS multiplexing transmission; for sTTI of 2OS, the current conclusion is to allow different sTTI to share DMRS, and the transmission position of DMRS is indicated by the base station.

The existing solution is to transmit the position of the DMRS through an uplink grant (UL grant), as shown in fig. 2, the left diagram in fig. 2 corresponds to a scheme that fixes the absolute position of the DMRS, and an indication (such as 00, 01, 10, or 11) of the absolute position of the DMRS transmission corresponding to the UL grant in each sTTI is transmitted through the UL grant in each sTTI, for example, 01 indicates that the DMRS transmission of the sTTI is located at the 2 nd DMRS position of 4 DMRSs in the left diagram; the right hand diagram in fig. 2 corresponds to the position of the DMRS in a fixed sTTI (i.e. the position of the DMRS in an sTTI is fixed, e.g. both on the first symbol position in an sTTI in the right hand diagram), by sending an indication of the position of the DMRS in the UL grant in each sTTI relative to the current sTTI, e.g. for the UL grant of sTTI 4, by 01 bits, it can be indicated that its DMRS transmission is located in its previous sTTI, i.e. in sTTI 3.

In the design of a 5G new air interface (NR), different subcarrier spacing designs are supported, and a shorter slot design also exists, such as a mini-slot, which includes more than or equal to 1 OFDM symbol, and in order to reduce the overhead of pilot transmission, multi-slot pilot sharing may also be supported.

It can be seen that the above solution can only indicate that certain 1 column of DMRS is employed. Considering that as sTTI is shortened, for some users, joint scheduling may be required for multiple sTTI, and at this time, multiple columns of DMRSs may be required for demodulation, and the existing solution cannot perform indication of multiple columns of DMRSs;

disclosure of Invention

The technical problem to be solved by the embodiments of the present invention is to provide a method and an apparatus for transmitting and receiving a demodulation reference signal, which can indicate a DMRS transmission position under a condition of sharing a DMRS.

To solve the above technical problem, an embodiment of the present invention provides a method for receiving and transmitting demodulation reference signals, including:

sending first scheduling information to a terminal, wherein the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, the first DMRS pattern is one of a preset pattern set, the preset pattern set comprises a plurality of DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of a plurality of DMRS candidate positions in a preset time-frequency range;

and determining the time domain and/or frequency domain position of DMRS transmission according to the first DMRS pattern, and transmitting or receiving the DMRS.

Preferably, in the above method, before transmitting the first scheduling information, the method further includes:

and sending set configuration information for indicating the preset mode set to a terminal.

Preferably, in the above method, before sending the set configuration information, the method further includes:

determining DMRS candidate positions which are possibly provided with DMRS in a preset time frequency range, and obtaining a plurality of combinations consisting of part or all of the DMRS candidate positions;

and determining the preset mode set according to all combinations or partial combinations in the multiple combinations.

Preferably, in the above method, the DMRS candidate positions include time-domain symbol positions and/or frequency-domain subcarrier positions where DMRSs may occur.

Preferably, in the above method, the predetermined time-frequency range includes: n time slots currently scheduled for transmission and M time slots before the current time slots, where M is an integer greater than 0 and N is an integer greater than 0.

Preferably, in the above method, the predetermined time-frequency range includes: all L symbols of a slot currently scheduled for transmission and P preceding symbols thereof, where L is an integer greater than 0 and P is an integer greater than or equal to 0.

Preferably, in the above method, the predetermined time-frequency range includes: the method comprises the steps of obtaining X DMRS candidate positions in a time slot of current scheduled transmission and Y DMRS candidate positions in one or more time slots before the time slot of the current scheduled transmission, wherein X and Y are integers which are larger than or equal to 0.

Preferably, in the above method, the predetermined time-frequency range further includes 1 or more minimum frequency-domain scheduling units.

Preferably, in the above method, the predetermined time-frequency range is predefined, or determined by the network side and notified to the terminal.

Another method for receiving and transmitting demodulation reference signals provided in the embodiments of the present invention includes:

receiving first scheduling information sent by a network side, wherein the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, the first DMRS pattern is one of a preset pattern set, the preset pattern set comprises a plurality of DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of a plurality of DMRS candidate positions in a preset time-frequency range;

Preferably, in the above method, before receiving the first scheduling information, the method further includes:

and receiving set configuration information which is sent by a network side and used for indicating the preset mode set.

Preferably, in the above method, the predetermined time-frequency range is predefined or obtained by receiving from the network side.

The embodiment of the invention provides a transceiver for demodulating reference signals, which comprises:

a scheduling unit, configured to send first scheduling information to a terminal, where the first scheduling information carries a first DMRS pattern for a first demodulation reference signal corresponding to currently scheduled transmission, where the first DMRS pattern is one of a preset pattern set, the preset pattern set includes multiple DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of multiple DMRS candidate positions in a predetermined time-frequency range;

and the transceiver unit is used for determining the time domain and/or frequency domain position of DMRS transmission according to the first DMRS pattern and transmitting or receiving the DMRS.

Preferably, the above apparatus further comprises:

a first sending unit, configured to send, to a terminal, set configuration information indicating the preset mode set before sending the first scheduling information.

Preferably, the above apparatus further comprises: a set determining unit, configured to determine DMRS candidate positions, where DMRSs may occur, within a predetermined time-frequency range before transmitting the set configuration information, and obtain multiple combinations of some or all of the DMRS candidate positions; and determining the preset mode set according to all combinations or partial combinations in the multiple combinations.

Preferably, in the above apparatus, the predetermined time-frequency range is predefined, or determined by the network side and notified to the terminal.

Another receiving and transmitting apparatus for demodulation reference signals provided in an embodiment of the present invention includes:

a first receiving unit, configured to receive first scheduling information sent by a network side, where the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, where the first DMRS pattern is one of a preset pattern set, the preset pattern set includes multiple DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of multiple DMRS candidate positions in a predetermined time-frequency range;

Preferably, the above apparatus further comprises:

a first receiving unit, configured to receive, before receiving the first scheduling information, set configuration information that is sent by a network side and used for indicating the preset mode set.

Preferably, in the above apparatus, the DMRS candidate positions include time-domain symbol positions and/or frequency-domain subcarrier positions where DMRSs may occur.

Preferably, in the above apparatus, the predetermined time-frequency range includes: n time slots currently scheduled for transmission and M time slots before the current time slots, where M is an integer greater than 0 and N is an integer greater than 0.

Preferably, in the above apparatus, the predetermined time-frequency range includes: all L symbols of a slot currently scheduled for transmission and P preceding symbols thereof, where L is an integer greater than 0 and P is an integer greater than or equal to 0.

Preferably, in the above apparatus, the predetermined time-frequency range includes: the method comprises the steps of obtaining X DMRS candidate positions in a time slot of current scheduled transmission and Y DMRS candidate positions in one or more time slots before the time slot of the current scheduled transmission, wherein X and Y are integers which are larger than or equal to 0.

Preferably, in the above apparatus, the predetermined time-frequency range further includes 1 or more minimum frequency-domain scheduling units.

Preferably, in the above apparatus, the predetermined time-frequency range is predefined or obtained by receiving from a network side.

Compared with the prior art, the method and the device for receiving and transmitting the demodulation reference signal provided by the embodiment of the invention can realize the indication of the DMRS transmission position under the condition of sharing the DMRS, and can realize the indication of different numbers and densities of the time domain symbols of the DMRS.

Drawings

Fig. 1 is a schematic diagram of DMRS in LTE PUSCH of the prior art;

fig. 2 is a diagram illustrating a position of transmitting a DMRS through a UL grant according to the related art;

fig. 3 is a flowchart illustrating a method for transceiving demodulation reference signals according to an embodiment of the present invention;

fig. 4 is another flowchart illustrating a method for transceiving a demodulation reference signal according to an embodiment of the present invention;

fig. 5 is an exemplary diagram of the position of a DMRS candidate position in the time domain according to an embodiment of the present invention;

fig. 6 is an exemplary diagram of the position of a DMRS candidate position on a frequency domain according to an embodiment of the present invention;

fig. 7 is a diagram illustrating DMRS pattern indication of example 1 according to an embodiment of the present invention;

fig. 8 is a diagram illustrating DMRS pattern indication of example 2 provided in an embodiment of the present invention;

fig. 9 is a diagram illustrating a DMRS pattern indication of example 3 according to an embodiment of the present invention;

fig. 10 is another schematic diagram of DMRS pattern indication of example 3 provided by an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a transceiver apparatus for demodulating reference signals according to an embodiment of the present invention;

fig. 12 is another schematic structural diagram of a transceiver apparatus for demodulating a reference signal according to an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments. In the following description, specific details such as specific configurations and components are provided only to help the full understanding of the embodiments of the present invention. Thus, it will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

It should be appreciated that reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

In various embodiments of the present invention, it should be understood that the sequence numbers of the following processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention. In addition, the terms "system" and "network," "terminal" and "user" are often used interchangeably herein.

In the embodiment of the present invention, the Base Station may be a Macro Base Station (Macro Base Station), a micro Base Station (Pico Base Station), a Node B (the name of a 3G mobile Base Station), an enhanced Base Station (eNB), a Home enhanced Base Station (Femto eNB or Home eNode B or Home eNB or HeNB), a relay Station, an access point, a Remote Radio Unit (RRU), a Remote Radio Head (RRH) Head, a network side Node in a 5G mobile communication system, such as a Central Unit (CU, Central Unit), a Distributed Unit (DU, Distributed Unit), and the like. The terminal may be a mobile phone (or handset), or other device capable of sending or receiving wireless signals, including a User Equipment (UE), a Personal Digital Assistant (PDA), a wireless modem, a wireless communicator, a handheld device, a laptop computer, a cordless phone, a Wireless Local Loop (WLL) station, a CPE (Customer Premise Equipment) or mobile smart hotspot capable of converting mobile signals to WiFi signals, a smart appliance, or other device capable of autonomously communicating with a mobile communication network without human operation, etc.

An embodiment of the present invention provides a method for transceiving a demodulation reference signal (DMRS), as shown in fig. 3, where the method is applied to a network side, such as a base station, and may include:

step 31, sending first scheduling information to a terminal, where the first scheduling information carries indication information of a first DMRS pattern corresponding to currently scheduled transmission, where the first DMRS pattern is one of a preset pattern set, the preset pattern set includes multiple DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of multiple DMRS candidate positions in a predetermined time-frequency range.

Here, the currently scheduled transmission refers to a currently scheduled time-frequency unit, which may be one TTI, one sTTI, one slot, or one mini-slot, or may be multiple TTIs, multiple sttis, multiple slots, or multiple mini-slots, and the number of OFDM symbols included in each scheduled time-frequency unit is not necessarily the same. The currently scheduled transmission may be a joint schedule of multiple time slots. The indication information of the first DMRS pattern may be an index of the first DMRS pattern in the preset pattern set.

And step 32, determining the time domain and/or frequency domain position of DMRS transmission according to the first DMRS pattern, and transmitting or receiving the DMRS.

Here, when the currently scheduled transmission is downlink transmission, the base station may transmit the first scheduling information and the DMRS corresponding to the first DMRS pattern in the currently scheduled transmission; when the currently scheduled transmission is uplink transmission, the base station may receive the DMRS sent by the terminal according to the position of the DMRS corresponding to the first DMRS pattern.

From the above steps, it can be seen that the embodiments of the present invention can be applied to the reception of the uplink DMRS and the transmission processing of the downlink DMRS. In step 31, the network performs transmission scheduling on the terminal through the first scheduling information, and the first scheduling information also carries a DMRS pattern corresponding to the currently scheduled transmission. Specifically, each DMRS pattern defines a combination of some or all of the plurality of DMRS candidate positions, that is, the combination may include only one DMRS candidate position or may include a plurality of DMRS candidate positions.

Through the steps, the embodiment of the invention can indicate the DMRS transmission position in the scene of sharing the DMRS, and can indicate different numbers and densities of time domain symbols aiming at the DMRS.

Of course, the preset mode set may also be determined by the network side and notified to the terminal through a high-level signaling or a system message, at this time, before step 31, the network side may also send set configuration information for indicating the preset mode set to the terminal, so that the terminal receives the set configuration information and configures the preset mode set locally. In addition, before transmitting the set configuration information, the network side may determine DMRS candidate positions in a predetermined time-frequency range, where DMRSs may occur, to obtain multiple combinations composed of part or all of the DMRS candidate positions, where any one combination may include only one DMRS candidate position, or may include more than 1 DMRS candidate positions, and then the network side determines the preset pattern set according to all combinations or part of the multiple combinations. To simplify the processing, only partial combinations may be extracted from the above-described plural combinations as a preset pattern set.

Referring to fig. 4, the method for transceiving a demodulation reference signal according to the embodiment of the present invention, when being applied to a terminal, may include:

step 41, receiving first scheduling information sent by a network side, where the first scheduling information carries a first demodulation reference signal DMRS pattern corresponding to currently scheduled transmission, the first DMRS pattern is one of a preset pattern set, the preset pattern set includes a plurality of DMRS patterns, and each DMRS pattern corresponds to a combination of part or all of a plurality of DMRS candidate positions within a predetermined time-frequency range.

And step 42, determining the time domain and/or frequency domain position of DMRS transmission according to the first DMRS pattern, and transmitting or receiving the DMRS.

Through the steps, the terminal can receive the scheduling information sent by the network side, and obtain the DMRS mode corresponding to the currently scheduled transmission according to the scheduling information, so as to determine the time domain and/or frequency domain position of the DMRS transmission according to the DMRS mode, and send or receive the DMRS.

Before step 41, the terminal may further receive set configuration information sent by the network side and used for indicating the preset mode set, so as to configure the preset mode set locally. Of course, as another way, the preset mode set at the terminal side may be configured in advance.

In the embodiment of the present invention, the preset mode set may be defined and configured by both the network side and the terminal side, for example, defined by a relevant standard.

In the embodiment of the invention, the DMRS candidate position refers to a time domain symbol position and/or a frequency domain subcarrier position where the DMRS is likely to occur. Specifically, the DMRS candidate position may be predefined, for example, defined by a relevant standard, or determined by the network side and notified to the terminal through higher layer signaling or system message. For example, for all time slots with DMRS candidate positions, the DMRS candidate positions are located on the first OFDM symbol of the time slot, so that a user can receive the DMRS first to perform channel estimation, which is helpful for reducing the time delay; or for all time slots with the candidate positions of the DMRS, the candidate positions of the DMRS are all positioned on the last OFDM symbol of the time slot, so that the delay of the channel obtained by the estimation of the DMRS when the channel is applied to the subsequent time slot is small, and the channel estimation error can be reduced. When the number of OFDM symbols included in the time slot is more than 2, the OFDM symbols may also be located on the middle OFDM symbol, so as to obtain the compromise between the delay and the shared channel estimation performance.

In an embodiment of the present invention, each DMRS pattern corresponds to a combination of some or all of the plurality of DMRS candidate locations within a predetermined time-frequency range. The predetermined time-frequency range is predefined, for example, defined by a relevant standard, or determined by the network side and notified to the terminal through a high-level signaling or a system message.

The frequency domain position where the DMRS may occur may be a predefined fixed position, and the fixed position may be defined by a relevant standard, or determined by the network side and notified to the terminal through a higher layer signaling or a system message, and then the time domain position of the DMRS candidate position is mainly concerned at this time.

As an implementation manner, at this time, the predetermined time-frequency range may include: the predetermined time frequency range comprises: n time slots currently scheduled for transmission and M time slots before the current time slots, where M is an integer greater than 0 and N is an integer greater than 0. The first M time slots here refer to M time slots adjacent to and before the currently scheduled time slot. For example, if the currently scheduled timeslots are timeslots 8 to 9, when M is 2, the first M timeslots refer to timeslots 6 to 7. When the number of the time slots scheduled at one time is different, the corresponding M value and N value may also be different, and M and N may be predefined according to the number of the scheduled time slots, or notified by a network side through a high-level signaling.

For example, in terms of time domain, it is assumed that each slot includes one possible DMRS candidate position, and if M + N is 4, as shown in fig. 5, there are DMRS candidate positions of 4 slots, which are a to D, and all combinations of time domains where they may appear are 15 groups, respectively:

when there are only 1 columns of DMRSs, there are 4 possibilities: a; b; c; d;

with two columns of DMRS, there are 6 possibilities: a + B; a + C; a + D; b + C; b + D; c + D;

with 3 columns of DMRS, there are 4 possibilities: a + B + C; a + B + D; a + C + D; b + C + D;

when all of the 4 columns of DMRSs are needed for demodulation of current data, there are only 1 possibility: a + B + C + D;

considering certain principles, such as reducing processing complexity, it is possible to take only a part of the above 15 combinations as a preset pattern set and then indicate the DMRS pattern in real time by bits. For example, when scheduling in a single time slot, only 1 column of DMRS patterns need to be considered; when multi-slot scheduling is carried out, when the number of scheduled slots is 2, assuming that only 1 column of DMRS is allowed to appear, only 1 column of DMRS modes are considered and indication is carried out; when the number of scheduled slots is 3 or 4, it is assumed that only 2 columns of DMRS patterns need to be considered. By the above limitation, the number of bits of the indication information of the DMRS pattern can be reduced.

In addition, in the embodiment of the present invention, the M value and the N value corresponding to different users may also be different, that is, the channel change of some users is slow, and the time slot capable of sharing the DMRS transmission position may be larger than the scheduled time slot, that is, the N value may be larger; for some users, the channel changes faster, and the value of N may be smaller. The network side can configure the M and N values for the user through high-layer signaling.

In addition, the reference starting positions of the counts of M and N can also be flexibly handled, for example, the count of M includes the first scheduled time slot, the count of N starts from the 2 nd scheduled time slot, or the total count value giving only one reference point at a certain time is calculated.

As another implementation manner, the predetermined time-frequency range may include: all L symbols of a slot currently scheduled for transmission and P preceding symbols thereof, where L is an integer greater than 0 and P is an integer greater than or equal to 0. The first P symbols here refer to P slots adjacent to and before the currently scheduled slot. For example, assume that each slot includes 2 symbols, the currently scheduled slot is slots 8-9, the scheduled slots 8-9 include symbols 15-18, and when P is 4, the first P symbols refer to symbols 11-14 in slots 6-7. When the number of the time slots scheduled at one time is different, the corresponding L value and P value may also be different, and L and P may be predefined according to the number of the scheduled time slots, or notified by a network side through a high-level signaling.

As another implementation manner, the predetermined time-frequency range may include: the method comprises the steps of obtaining X DMRS candidate positions in a time slot of current scheduled transmission and Y DMRS candidate positions in one or more time slots before the time slot of the current scheduled transmission, wherein X and Y are integers which are larger than or equal to 0. Here, the previous one or more time slots of the time slot currently scheduled for transmission refer to one or more time slots adjacent to and prior to the currently scheduled time slot. When the number of the time slots scheduled at one time is different, the corresponding X value and Y value may also be different, and the X value and the Y value may be predefined according to the number of the scheduled time slots, or notified by a network side through a high-level signaling.

The time domain position where the DMRS may occur may be a predefined fixed position, and the fixed position may be defined by a relevant standard, or determined by the network side and notified to the terminal through a high layer signaling or a system message, and then the frequency domain position of the DMRS candidate position is mainly concerned at this time. Specifically, the predetermined time-frequency range may include 1 or more minimum frequency-domain scheduling units, such as one or more Resource Blocks (RBs).

The frequency domain location of the DMRS candidate location may also be indicated in a similar manner to the time domain location. For example, as shown in fig. 6, it is assumed that there are DMRS candidate positions on slot 0 and slot 2 of 4 slots (slots) defined in advance. In the frequency domain, there are 4 frequency domain positions a to d in each minimum frequency domain scheduling unit (here, RB is taken as an example for explanation), and through different combinations of the frequency domain positions, a preset mode set composed of the different combinations is obtained, and then in step 31, indication of a corresponding mode is performed, and indication of the frequency domain position can also be achieved.

Taking fig. 6 as an example:

if there is DMRS on only one subcarrier per RB, there are 4 possibilities: a; b; c; d;

if there can be DMRS on 2 subcarriers, there are 6 possibilities: a + b; a + c; a + d; b + c; b + d; c + d;

if DMRS can be transmitted on 3 subcarriers, there are 4 possibilities: a + b + c; a + b + d; a + c + d; b + c + d;

DMRS is transmitted fully on 4 carriers, 1 possible: a + b + c + d;

similarly, a part of all combinations may be taken as a preset pattern set for indication.

The predetermined time-frequency range of the embodiment of the present invention may include: time domain location and frequency domain location. Specifically, the time domain position may be any one of the above 3 implementation manners, and the frequency domain position may be a minimum frequency domain scheduling unit. At this time, the predetermined time-frequency range may be predefined according to the number of scheduled time slots, or notified by the network side through a high-level signaling. Of course, the predetermined time-frequency range may also be represented in other ways, which are limited to space, and are not illustrated here.

In the following, specific examples of DMRS pattern indication are described with reference to the drawings, and in the following examples, specific DMRS patterns are indicated by the network side through control information. Each rectangular box in fig. 7 to 10 represents a slot, and each slot includes 2 time domain symbols:

example 1

By supporting N greater than 1, DMRSs within other transmission elements (e.g., slots) may be supported, as shown in fig. 7, assuming that N is 3 and M is 1, by indicating that the DMRS pattern is DMRS pattern a, DMRS transmission representing the last scheduled slot in fig. 7 is transmitted in the 3 rd slot before the last scheduled slot.

Example 2

Through the DMRS pattern, simultaneous sharing of multiple DMRSs can be supported, as shown in fig. 8, the DMRS is scheduled to 2 slots at a time, and DMRSs sharing the first 1 and the first 3 slots of the scheduled slot can be supported by indicating a DMRS pattern k corresponding to the 2 columns of DMRS candidate positions in fig. 8.

Example 3

When multiple slots are scheduled, the sending density of the DMRS can be adjusted through the DMRS pattern; as shown in fig. 9 and 10, different DMRS patterns correspond to different DMRS densities. In addition, when multiple columns of DMRS candidate positions exist in a single slot, the density of DMRS scheduled by the single slot can be adjusted through the DMRS mode.

The indication information of the DMRS mode in the embodiment of the invention can be indicated through a specific mode index. Another way of the above indication information is to allocate a corresponding bit (bit) to each DMRS candidate position that may occur within a predetermined time-frequency range, and indicate a DMRS pattern in the form of a bitmap (bitmap). For example, for fig. 9, DMRSs are indicated to be located in 1 st and 3 rd slots by a bitmap "1010", and for fig. 10, DMRSs are indicated to be transmitted in each slot by a bitmap "1111".

In the embodiment of the invention, the bit number required by mode indication can be reduced by selecting part of DMRS modes to form the preset mode set.

The above describes a method for transmitting and receiving demodulation reference signals according to an embodiment of the present invention, and the following further describes an apparatus for implementing the method.

Referring to fig. 11, an embodiment of the present invention provides a transceiver for demodulating reference signals, which may be disposed on a network side, such as a base station, and as shown in fig. 11, the transceiver specifically includes:

the scheduling unit 111 is configured to send first scheduling information to a terminal, where the first scheduling information carries a first DMRS pattern for a first demodulation reference signal corresponding to currently scheduled transmission, where the first DMRS pattern is one of a preset pattern set, the preset pattern set includes multiple DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of multiple DMRS candidate positions in a predetermined time-frequency range.

A transceiver unit 112, configured to determine a time domain and/or a frequency domain position of DMRS transmission according to the first DMRS pattern, and perform sending or receiving of the DMRS.

As a preferable mode, the above apparatus may further include:

A set determining unit, configured to determine DMRS candidate positions, where DMRSs may occur, within a predetermined time-frequency range before transmitting the set configuration information, and obtain multiple combinations of some or all of the DMRS candidate positions; and determining the preset mode set according to all combinations or partial combinations in the multiple combinations.

In the above apparatus, the predetermined time-frequency range is predefined, or determined by the network side and notified to the terminal.

In the above apparatus, the DMRS candidate positions include time-domain symbol positions and/or frequency-domain subcarrier positions where DMRSs may occur.

In the above apparatus, the predetermined time-frequency range includes: n time slots currently scheduled for transmission and M time slots before the current time slots, where M is an integer greater than 0 and N is an integer greater than 0.

In the above apparatus, the predetermined time-frequency range includes: all L symbols of a slot currently scheduled for transmission and P preceding symbols thereof, where L is an integer greater than 0 and P is an integer greater than or equal to 0.

In the above apparatus, the predetermined time-frequency range includes: the method comprises the steps of obtaining X DMRS candidate positions in a time slot of current scheduled transmission and Y DMRS candidate positions in one or more time slots before the time slot of the current scheduled transmission, wherein X and Y are integers which are larger than or equal to 0.

In the above apparatus, the predetermined time-frequency range further includes 1 or more minimum frequency-domain scheduling units.

In the above apparatus, the predetermined time-frequency range is predefined or obtained by receiving from the network side.

Referring to fig. 12, an embodiment of the present invention provides a transceiver apparatus for demodulating reference signals, which may be disposed at a terminal side, such as a base station, and as shown in fig. 12, the apparatus specifically includes:

a first receiving unit 121, configured to receive first scheduling information sent by a network side, where the first scheduling information carries a first demodulation reference signal DMRS pattern corresponding to currently scheduled transmission, where the first DMRS pattern is one of a preset pattern set, the preset pattern set includes multiple DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of multiple DMRS candidate positions in a predetermined time-frequency range.

A transceiver unit 122, configured to determine, according to the first DMRS pattern, a time-domain and/or frequency-domain position of DMRS transmission, and perform sending or receiving of the DMRS.

Preferably, the above apparatus further comprises:

In summary, the method and the apparatus for transceiving demodulation reference signals according to the embodiments of the present invention can implement the indication of DMRS transmission positions under the condition of sharing DMRSs, and can implement the indication of different numbers and densities of time domain symbols of DMRSs.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for transceiving demodulation reference signals, comprising:

sending first scheduling information to a terminal, wherein the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, the first DMRS pattern is one of a preset pattern set, the preset pattern set comprises a plurality of DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of a plurality of DMRS candidate positions in a preset time-frequency range; the predetermined time-frequency range comprises: n time slots and the first M time slots of a currently scheduled transmission, where M is an integer greater than 0 and N is an integer greater than 0, or all L symbols and the first P symbols of a time slot of a currently scheduled transmission, where L is an integer greater than 0 and P is an integer greater than 0, or X DMRS candidate positions in a time slot of a currently scheduled transmission and Y DMRS candidate positions in one or more time slots before a time slot of a currently scheduled transmission, where X is an integer greater than 0 and Y is an integer greater than 0;

2. The method of claim 1, wherein prior to transmitting the first scheduling information, the method further comprises:

3. The method of claim 2, wherein prior to sending the set configuration information, the method further comprises:

4. The method of claim 1,

the DMRS candidate positions include time domain symbol positions and/or frequency domain subcarrier positions where DMRSs may occur.

5. The method of claim 1, wherein the predetermined time-frequency range further comprises 1 or more minimum frequency-domain scheduling units.

6. The method of claim 1, wherein the predetermined time-frequency range is predefined or determined by a network side and notified to a terminal.

7. A method for transceiving demodulation reference signals, comprising:

receiving first scheduling information sent by a network side, wherein the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, the first DMRS pattern is one of a preset pattern set, the preset pattern set comprises a plurality of DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of a plurality of DMRS candidate positions in a preset time-frequency range; the predetermined time-frequency range comprises: n time slots and the first M time slots of a currently scheduled transmission, where M is an integer greater than 0 and N is an integer greater than 0, or all L symbols and the first P symbols of a time slot of a currently scheduled transmission, where L is an integer greater than 0 and P is an integer greater than 0, or X DMRS candidate positions in a time slot of a currently scheduled transmission and Y DMRS candidate positions in one or more time slots before a time slot of a currently scheduled transmission, where X is an integer greater than 0 and Y is an integer greater than 0;

8. The method of claim 7, wherein prior to receiving the first scheduling information, the method further comprises:

9. The method of claim 7,

10. The method according to any of claim 7, wherein the predetermined time-frequency range further comprises 1 or more minimum frequency-domain scheduling units.

11. The method of claim 7, wherein the predetermined time-frequency range is predefined or received from a network side.

12. A transceiver apparatus for demodulating a reference signal, comprising:

the scheduling unit is used for sending first scheduling information to a terminal, wherein the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, the first DMRS pattern is one of a preset pattern set, the preset pattern set comprises a plurality of DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of a plurality of DMRS candidate positions in a preset time-frequency range; the predetermined time-frequency range comprises: n time slots and the first M time slots of a currently scheduled transmission, where M is an integer greater than 0 and N is an integer greater than 0, or all L symbols and the first P symbols of a time slot of a currently scheduled transmission, where L is an integer greater than 0 and P is an integer greater than 0, or X DMRS candidate positions in a time slot of a currently scheduled transmission and Y DMRS candidate positions in one or more time slots before a time slot of a currently scheduled transmission, where X is an integer greater than 0 and Y is an integer greater than 0;

13. The transceiver apparatus of claim 12, further comprising:

14. The transceiver apparatus of claim 13, further comprising:

15. The transceiver apparatus as claimed in claim 12, wherein the predetermined time-frequency range is predefined or determined by the network side and notified to the terminal.

16. A transceiver apparatus for demodulating a reference signal, comprising:

a first receiving unit, configured to receive first scheduling information sent by a network side, where the first scheduling information carries a first demodulation reference signal (DMRS) pattern corresponding to currently scheduled transmission, and the first DMRS pattern is one of a preset pattern set, where the preset pattern set includes multiple DMRS patterns, and each DMRS pattern corresponds to one combination of part or all of multiple DMRS candidate positions in a predetermined time-frequency range; the predetermined time-frequency range comprises: n time slots and the first M time slots of a currently scheduled transmission, where M is an integer greater than 0 and N is an integer greater than 0, or all L symbols and the first P symbols of a time slot of a currently scheduled transmission, where L is an integer greater than 0 and P is an integer greater than 0, or X DMRS candidate positions in a time slot of a currently scheduled transmission and Y DMRS candidate positions in one or more time slots before a time slot of a currently scheduled transmission, where X is an integer greater than 0 and Y is an integer greater than 0;

17. The transceiver apparatus of claim 16, further comprising:

18. Transceiver apparatus according to claim 12 or 16,

19. The transceiver apparatus of claim 12 or 16, wherein the predetermined time-frequency range further comprises 1 or more minimum frequency-domain scheduling units.

20. The transceiver apparatus as claimed in claim 16, wherein the predetermined time-frequency range is predefined or obtained from network side reception.