TW201828755A - Method and apparatus for transmitting signals - Google Patents

Abstract

Methods and apparatus for transmitting signals are provided. In a 1-port DMRS design, two REs in a RE set are configured for DMRS and rest REs are configured for PDCCH. Alternatively, two REs in a RE set are configured for DMRS, two null REs are configured for power boosting, and the rest REs are configured for PDCCH.

Description

Method and equipment for transmitting signals

The present application relates to the field of communications, and more particularly, to a method and device for transmitting signals.

In the long term evolution (LTE) R8 (Rel-8) version, a cell-specific reference signal (CRS) is used for demodulation of a physical downlink control channel (PDCCH), and The number of CRS ports is cell-specific. In the LTE R11 (Rel-11) version, a DMRS (1-port) demodulation reference signal (DMRS) with one antenna port is dedicated to locally enhanced PDCCH (EPDCCH) demodulation DMRS with two antenna ports (for short, 2-port) is dedicated to distributed EPDCCH demodulation.

In a 5G new radio (NR, new radio) system, DMRS can be used for PDCCH decoding. Therefore, a new NR PDCCH DMRS design is needed to meet the needs of 5G NR.

In this application, DMRS is used for PDCCH decoding, and some DMRS designs are proposed for 5G NR PDCCH, such as a DMRS design with one antenna port (for short, 1-port DMRS) design and a DMRS with two antenna ports (for short, 2 -Port DMRS) design, etc. In addition, specific DMRS port configurations for user equipment (UE) are also proposed.

In one implementation, the techniques of this application include providing a method of transmitting a signal. In this method, a 1-port DMRS for an NR PDCCH may use two REs in a resource element set (RE set, resource element set) for the DMRS, and use the remaining REs for the PDCCH.

In one implementation method, the techniques of this application include providing a method of transmitting a signal. In this method, the 1-port DMRS for the NR PDCCH may use four REs in one resource element set for the DMRS, and use the remaining REs for the PDCCH.

In one implementation, the techniques of this application include providing a method of transmitting a signal. In this method, two REs in one resource element set are used for DMRS, two null REs in the resource element set are used for power boost, and the remaining REs in the resource element set are used for the PDCCH.

In one implementation, the techniques of this application include providing a method of transmitting a signal. In this method, the 2-port DMRS for the NR PDCCH can use four REs in the resource element set for the DMRS and the remaining REs in the PRB for the PDCCH.

It should be understood that the terms "system" and "network" are often used interchangeably herein. The term "and / or" in this document is only an association relationship describing related objects, which means that there can be three kinds of relationships. For example, A and / or B can mean: A alone exists, A and B exist simultaneously, and B alone three conditions. In addition, the character "/" in this article generally indicates that the related objects are an "or" relationship.

The embodiments of the present application will be described below with reference to the drawings.

FIG. 1 illustrates a wireless communication system 100 according to an embodiment of the present application. The wireless communication system 100 shown in FIG. 1 can operate in a high frequency band, which includes, but is not limited to, a long term evolution (LTE) system, a future evolution fifth-generation (5G) system, and a new radio (NR) Systems, and machine-to-machine (M2M) systems. The wireless communication system 100 shown in FIG. 1 is only used to exemplarily describe the technical solution of the embodiment of the present application, rather than to limit the scope of the embodiment of the present application. Those with ordinary knowledge in the technical field will understand that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions proposed in this article can also be used to solve similar technical problems that arise therein.

As shown in FIG. 1, the wireless communication system 100 may include one or more network devices 101, one or more terminals 103, and a core network 111.

The network device 101 may be a base station, which may communicate with one or more terminals, and may also communicate with a base station having a terminal function. In the 5G NR system, the base station may be gNB (g-Node B). The terminals 103 may be distributed in the wireless communication system 100. The terminal 103 may be a static ground or a mobile ground. In some embodiments, the terminal 103 may be a mobile device, a mobile station, a mobile unit, an M2M terminal, a wireless unit, a remote unit, a user agent, a mobile client, and so on. The network device 101 can communicate with the terminal 103 under the control of the controller. To simplify the description, the controller is not labeled in the drawing. In some embodiments, the controller may be part of the core network 111. In another embodiment, the controller may be integrated into the network device 101. The network devices 101 can communicate through a backhaul interface 107 such as an X2 interface. The network device 101 may be used to transmit control information or user data to the core network 111 through a backhaul interface 109 such as an S1 interface. The terminal 103 may be located within the coverage of one or more cells 105.

FIG. 2 illustrates a terminal 200. The terminal 200 may include one or more processors 201 or microprocessors 201, memory 202, communication interface 203, transmitter 205, receiver 206, coupler 207, antenna 208, user interface 209, input / output device 210, etc. . The above components may be connected through the bus 204. The terminal 200 can communicate with other communication devices such as a network device through the communication interface 203. The transmitter 205 may be used to transmit a signal output from the processor 201. The input / output device 210 may be used to implement interaction between the terminal 200 and an external environment. The memory 202 is coupled to the processor 201 and is used to store various computer-readable instructions or program code. The terminal processor 201 may be configured to read and execute the foregoing instructions or program codes stored in the terminal memory 202 to implement related functions or operations described in the embodiments of the present application.

FIG. 3 illustrates a network device 300. The network device 300 may be a gNB. The network device 300 may include at least one processor 301, a memory 302, a communication interface 303, a transmitter 305, and a receiver 306. The aforementioned components may be connected through a bus 304. In addition, as shown in FIG. 3, the network device 300 may further include a coupler 307 and an antenna 308 connected to the coupler 307. The communication interface 303 can be used for the network device 300 to communicate with other communication devices. For example, other communication devices may be other network devices or terminal devices. The transmitter 305 may be used to transmit a signal from the processor 301 to the outside. The processor 301 may be used for wireless signal management, communication link establishment, and cell switching control of users in the control area. The processor 301 is configured to read an instruction or program code stored in the memory 302 to perform related operations and implement related functions provided in the embodiments of the present application.

FIG. 4 shows a PDCCH cell-specific reference signal (CRS) design in an LTE system. As shown in FIG. 4, in the LTE system, the PDCCH is transmitted on the first several orthogonal frequency division multiplexing (OFDM) symbols located across the entire system bandwidth at the beginning of the subframe. It can be seen from FIG. 4 that, for example, the time length of the PDCCH may be three symbols. A physical resource block (PRB) occupies twelve subcarriers in the frequency domain. Among them, two REs in one resource element set are used for CRS port # 0, and two REs are used for CRS port # 1. CRS is used to demodulate the PDCCH and supports 2-port CRS and 4-port CRS, where "port" refers to "antenna port". In the LTE system, the CRS port is cell-specific. Therefore, the CRS port does not change based on a single user equipment (UE, user equipment). In the LTE R11 version, 1-port DMRS is dedicated to centralized EPDCCH demodulation, and 2-port DMRS is dedicated to distributed EPDCCH demodulation.

In a 5G NR system, DMRS can be used for PDCCH decoding and can support 1-port DMRS and / or 2-port DMRS. The technical solutions provided by the embodiments of the present application include a 1-port DMRS design and a 2-port DMRS design and a UE-specific DMRS port configuration for 5G NR, which can meet the requirements in a 5G NR system. The technical solution of the embodiment of the present application can be used for transmitting signals and the like.

Since the DMRS is used for the PDCCH and can be embedded and transmitted in the PRB carrying the PDCCH, the number of DMRS ports can be UE-specific and can be semi-statically configured by using higher layer signals or signals based on the UE. For example, if the UE is in the center of the cell and therefore does not need transmission diversity to improve its PDCCH performance, the UE can be configured with a 1-port DMRS, and the exemplary DMRS design shown in any of Figures 5 to 8 can be used PDCCH demodulation for the UE. For another UE located at the cell edge, it may need transmission diversity to improve its PDCCH performance or increase coverage. For this UE, a 2-port DMRS can be configured and the exemplary DMRS design shown in FIG. 9 can be used.

The "resources" referred to herein are time-frequency resources, including time-domain resources and frequency-domain resources. The form of the resource may generally be, but not limited to, a resource element (RE), a resource block (RB), a symbol, a carrier (subcarrier), a transmission time interval (TTI, transmission time interval), and the like. For those with ordinary knowledge in the technical field, the definition of concepts such as resource particles and resource blocks can refer to the LTE standard. However, the embodiments of the present application are not limited to the LTE standard. The definitions of various resource forms involved in the embodiments of the present application may change in future communication standards, but this does not affect the essence of the embodiments of the present application. In the following description, a physical resource block (PRB) and a RE are used as examples for illustration. It should be noted that the terms and words used herein are merely exemplary, and are not intended to limit the embodiments of the present application in any way.

PRB: PRB is a time-frequency resource occupying twelve subcarriers in the frequency domain and fourteen OFDM symbols in the time domain.

RE: RE is a time-frequency resource that occupies one subcarrier in the frequency domain and one symbol in the time domain. One PRB consists of twelve REs.

In one embodiment, the number of DMRS ports (referred to as DMRS ports) used for the NR PDCCH may be configured semi-statically based on each UE, for example, configured by higher layer signals. For example, the DMRS port configuration for the NR PDCCH may be performed in combination with the DMRS port configuration for the PDSCH, or may be performed separately. Specifically, the DMRS port configuration for the downlink (DL, downlink) PDCCH may be combined with the DMRS configuration for data (the data may be transmitted on a physical downlink shared channel (PDSCH)). For example, although the DMRS port index for PDCCH and PDSCH may vary with the pattern and density of DMRS, both PDCCH and PDSCH can be configured with 1-port DMRS. Another alternative is that the number of DMRS ports used for the PDCCH can be configured as one port, and the number of DMRS ports used for the PDSCH can be configured as two to eight ports, which is not limited in the embodiments of the present application.

A 1-port DMRS design and a 2-port DMRS design for the PDCCH will be described below.

Used for 5G NR systematic 1- port DMRS design

In FIGS. 5 to 8, DMRS port # 0 is taken as an example for description.

Embodiment 1

Figure 5 shows a 1-port DMRS design for the PDCCH. In the example shown, two REs in a resource element set can be used for DMRS (dark blocks in FIG. 5, hereinafter, simply referred to as "REs for DMRS"), and the remaining ten REs are used For the PDCCH (the light-colored blocks in FIG. 5 are hereinafter simply referred to as "REs for the PDCCH"). Accordingly, in the method for transmitting a signal, two REs in the resource element set are used to transmit the DMRS, and the remaining ten REs in the PRB are used to transmit the PDCCH. A "resource element set" refers to a resource element in a physical resource block (PRB) of an OFDM symbol.

The positions of two REs for DMRS, in other words, the number of REs for PDCCH between two REs for DMRS can be flexibly configured. In the example shown in FIG. 5, between two REs for DMRS, there are an even number (ie, six) of REs for PDCCH; while in the example shown in FIG. 6, between two Between REs used for DMRS, there are an odd number (ie, three) of REs used for PDCCH. Any other similar configuration may be adopted, and the embodiment of the present application has no limitation on this. As an implementation manner, the position of the RE used for the DMRS may consider DMRS density, gaps in channel estimation, and the like. Considering the channel response, REs for DMRS in a resource element set (in other words, a physical resource block) can be evenly and discretely distributed on the PRB to obtain a more accurate channel estimation result in the PRB.

Compared to the LTE CRS design shown in FIG. 4, the 1-port DMRS design for PDCCH shown in FIG. 5 or FIG. 6 can provide a frequency gap / density similar to LTE. Therefore, it can provide similar LTE Channel estimation performance.

Embodiment 2

Figure 7 shows another 1-port DMRS design for the PDCCH. In this design, based on the DMRS design of FIG. 5, in the resource element set, two empty REs are created (ie, used) for power boosting. An empty RE refers to an RE that is neither used for DMRS nor for PDCCH. As shown in FIG. 7, the empty RE (blank block in FIG. 7) may be adjacent to the RE for DMRS (dark block in FIG. 7), for example, the empty RE may be located to the left or right of the RE for DMRS . In this case, eight REs (light blocks in FIG. 7) remain for the PDCCH. Accordingly, in the method for transmitting signals, two REs in the resource element set are configured for transmitting DMRS, two empty REs are configured for power boost, and the remaining eight REs in the resource element set are configured for PDCCH transmission.

Embodiment 3

FIG. 8 shows another 1-port DMRS design for the PDCCH, where four REs in the resource element set can be used for the DMRS, and the remaining REs can be used for the PDCCH. As shown in FIG. 8, all four dark-colored REs in the PRB can be used to carry the 1-port DMRS, so the same power boosting effect as shown in FIG. 7 can be achieved. These four REs for DMRS can be divided into two pairs, and each pair of REs includes two adjacent REs to achieve multiplexing and obtain diversity gain. Orthogonal coverage codes can be added to the top reference signals sent on each adjacent pair of REs, which can mitigate interference from DMRS (assuming they use the same RE pair) from other cells.

Compared with the design shown in FIG. 5 or FIG. 6, although this change shown in FIG. 7 or FIG. 8 reduces the number of REs used for PDCCH in resource elements from ten to eight, because An empty RE or an adjacent RE borrows power, so power improvement can also be achieved, thereby improving channel estimation accuracy.

Used for 5G NR systematic 2- port DMRS design

FIG. 9 shows an example of a 2-port DMRS for a PDCCH. In FIG. 9, DMRS port # 0 and DMRS port # 1 are taken as an example for description. In the example shown in FIG. 9, in the resource element set, two pairs of REs (dark blocks in FIG. 9) are configured for DMRS, and the remaining eight REs are configured for PDCCH. Each pair of REs includes two adjacent REs.

For each pair of REs used for DMRS, frequency division multiplexing (FDM) or code division multiplexing (CDM) can be applied to obtain 2-port DMRS. The density and gap between each pair of REs takes into account channel estimates. Compared to the case of 1-port DMRS, in this 2-port DMRS design, for the location of the RE, in addition to the DMRS density and gap of the channel estimate, the application of transmission diversity (such as space-frequency block code (SFBC Space-frequency block code)). Based on this, as shown in FIG. 9, between two pairs of REs for DMRS, there may be an even number of REs for PDCCH.

Similarly, the number of DMRS ports for the NR PDCCH can be configured semi-statically on a per UE basis, that is, configured by higher layer signals or signals. As an implementation manner, the number of DMRS ports used for the NR PDCCH may be configured in combination with the DMRS port configuration used for the PDSCH, or may be configured separately.

Compared to the LTE CRS design shown in FIG. 4, the 2-port DMRS design for PDCCH shown in FIG. 9 can provide a frequency gap / density similar to LTE, and thus can provide channel estimation performance similar to LTE.

Used for 1- port DMRS or 2- port DMRS Unified design

The 1-port DMRS configuration shown in FIGS. 7 and 8 can generate the same RE mapping as the 2-port DMRS configuration shown in FIG. 9, so the same number of RE configurations can be used for the PDCCH in each PRB (As mentioned above, it is also referred to as a resource element group (REG) or resource element set for a PDCCH), without having to consider the number of DMRS antenna ports, which can facilitate the unified design of the PDCCH. In other words, regardless of whether it is a 1-port DMRS or a 2-port DMRS, eight REs are configured for the PDCCH.

According to an embodiment of the present application, a device for transmitting a signal is also provided. In a specific implementation, the device may use the DMRS design described above, and may be configured to perform the method for transmitting signals described above.

FIG. 10 is a block diagram for transmitting a signal according to an embodiment of the present application. As shown in FIG. 10, a device 40 may include a configuration unit 42 and a transmission unit 44. The device 40 may be configured on the gNB side and may communicate with the user equipment. The configuration unit 42 may be a processor integrated with a resource configuration function. The transmission unit 44 may be a transmitter, a receiver, an antenna, a wireless transmission device, or any other device integrated with a transmission function.

In the process of transmitting signals, the configuration unit 42 may be configured to configure resources for carrying DMRS. Among them, the resources for carrying DMRS are two REs for 1-port DMRS or 2-port DMRS, and may also be four. RE. The configuration of resources can be performed based on one or more of DMRS density, channel estimation gap, and transmit diversity.

As an implementation manner, for a 1-port DMRS, the resources configured for the DMRS may be two REs or four REs. In the case of two REs, the configuration unit 42 may distribute the two REs uniformly or discretely on the PRB to obtain a more accurate channel estimation result of the PRB. In the case of four REs, the configuration unit 42 may allocate the four REs as two pairs of REs, where each pair of REs includes two adjacent REs. For the 2-port DMRS, the resources configured by the configuration unit 42 for the DMRS are four REs, and similar to the case of the 1-port DMRS, these four REs can be allocated as two pairs of REs, where each pair of REs includes two Neighboring RE to achieve multiplexing and diversity gain.

As another implementation manner, in a case where two REs are configured for 1-port DMRS, the configuration unit 42 may also configure two empty REs for power boosting. Each of the two empty REs is adjacent to one of the two REs for the DMRS, and an even number of REs for the PDCCH may be separated between the two empty REs. For details of the configuration, reference may be made to the above description in conjunction with FIG. 7.

In the process of transmitting a signal, the transmission unit 44 may be configured to transmit a DMRS on a resource configured by the configuration unit 42.

The details described in the foregoing embodiments of the method for transmitting signals are also applicable to the device for transmitting signals according to the embodiments of the present application, and therefore will not be repeated.

Certain aspects of the technical solutions provided by the embodiments of the present application may be implemented as computer program toads or software. Specific examples include, but are not limited to, a computer-readable storage medium or a non-volatile machine-readable medium storing instructions and the like. The instructions may be used to program a computer system (or other electronic device) or processor to perform processing according to embodiments of the present application. Non-volatile machine-readable media include any mechanism for storing information in a form readable by a machine (eg, a computer) (eg, software, processing applications). The forms of non-volatile machine-readable media include, but are not limited to, magnetic storage media, optical storage media (eg, CD-ROM), magneto-optical storage media, ROM (read only memory), and random access memory ( RAM, random access memory), erasable programmable memory, flash memory, etc.

Based on this, FIG. 11 shows a device 50 having a processor 52 and one or more interfaces 56, such as a general purpose input / output (GPIO). The one or more interfaces 56 are connected to the processor 52 via a bus 54.

The processor 52 may be used to read and execute computer-readable instructions. In one embodiment, the processor 52 may include a controller, an operator, and a register. The hardware architecture of the processor 52 may be an application specific integrated circuit (ASIC) architecture, a microprocessor, a network processor, or the like.

The interface 56 may be used to input data to be processed to the processor 52 or output a processing result of the processor 52 to the outside. The interface 56 can be connected to peripheral devices such as a display, a camera, a radio frequency antenna, and the like.

With reference to the technical solution of the embodiment of the present application, the processor 52 may call a program for a method for transmitting signals from a memory, and execute instructions included in the program to implement a corresponding operation, such as the resource allocation operation described above. The interface 56 can be used to output the result of resource configuration, so that the transmitter or transceiver can transmit signals on the configured resource.

By means of the technical solution provided by the embodiments of the present application, a new NR PDCCH DMRS is provided to meet the requirements of the 5G NR system.

The above is only a specific implementation of the present application, but the scope of protection of the present application is not limited to this. Any person in the technical field who has common sense can easily think of changes or replacements within the technical scope disclosed in this application. All should be covered by the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the patent application scope.

100‧‧‧Wireless communication system

105‧‧‧Community

107, 109‧‧‧backhaul interface

111‧‧‧ Core Network

103, 200‧‧‧ terminal

201, 301, 52‧‧‧ processors

202, 302‧‧‧Memory

203, 303‧‧‧communication interface

204, 304, 54‧‧‧ bus

205, 305‧‧‧ launchers

206, 306‧‧‧ receiver

207, 307‧‧‧ coupler

208, 308‧‧‧ antenna

209‧‧‧user interface

210‧‧‧ input / output devices

101, 300‧‧‧ network equipment

40, 50‧‧‧ equipment

42‧‧‧Configuration Unit

44‧‧‧Transmission Unit

56‧‧‧Interface

This application will be better understood from the following description taken in conjunction with the drawings. In the scheme:

FIG. 1 illustrates a wireless communication system.

Figure 2 shows a terminal.

Figure 3 shows a network device.

Figure 4 shows a PDCCH CRS design for LTE.

FIG. 5 is a schematic diagram illustrating a PDCCH 1-port DMRS design for a 5G NR according to an embodiment of the present application.

FIG. 6 is a schematic diagram illustrating another PDCCH 1-port DMRS design for 5G NR according to an embodiment of the present application.

FIG. 7 is a schematic diagram showing yet another PDCCH 1-port DMRS design for 5G NR according to an embodiment of the present application.

FIG. 8 is a schematic diagram showing yet another PDCCH 1-port DMRS design for 5G NR according to an embodiment of the present application.

FIG. 9 is a schematic diagram illustrating a PDCCH 2-port DMRS design for 5G NR according to an embodiment of the present application.

FIG. 10 is a block diagram showing a structure of a device for transmitting a signal according to an embodiment of the present application.

FIG. 11 is a block diagram of a device according to an embodiment of the present invention.

Claims (10)

A method for transmitting a signal, comprising: using two resource elements (RE) in a resource element set to transmit a demodulation reference signal (DMRS) for a physical downlink control channel (PDCCH) reference signal), wherein the DMRS is a 1-port DMRS, and the resource element set is an RE in a physical resource block (PRB) of an orthogonal frequency division multiplexing symbol. The method according to item 1 of the scope of patent application, wherein the method further comprises: configuring two empty REs in the resource element set. The method according to item 2 of the scope of the patent application, wherein each resource element in the two empty REs is adjacent to one of the two REs for transmitting DMRS, respectively. The method according to item 3 of the scope of patent application, wherein an odd number of REs for transmitting a PDCCH are inserted between the two empty REs. The method according to item 2 of the scope of patent application, wherein the method further comprises: using a remaining RE in the resource element set to transmit a PDCCH, wherein the remaining RE refers to removing the PRB for transmitting a DMRS The two REs and REs other than the two empty REs. The method according to any one of claims 1 to 5, wherein the RE used for transmitting DMRS is configured based on a user equipment. The method according to any one of claims 1 to 5, wherein the REs used to transmit DMRS are configured by higher layer signals. The method according to any one of claims 1 to 5, wherein a location of the RE for transmitting DMRS is determined based on at least one of a DMRS density and a channel estimation gap. The method according to any one of claims 1 to 5, wherein the number of ports is configured by at least one of the following: based on a user equipment and configured via a higher-layer signal; and DMRS port configuration for physical downlink shared channel (PDSCH). A device for transmitting signals, comprising: a memory for storing machine-executable instructions; and a processor coupled to the memory and for invoking the machine-executable instructions stored in the memory to execute The method according to any one of claims 1 to 9 of the scope of patent application.