WO2017027996A1

WO2017027996A1 - Method and device for transmitting downlink signal, method and device for receiving same

Info

Publication number: WO2017027996A1
Application number: PCT/CN2015/086916
Authority: WO
Inventors: 彭晶波; 张劲林
Original assignee: 华为技术有限公司
Priority date: 2015-08-14
Filing date: 2015-08-14
Publication date: 2017-02-23
Also published as: CN107852615A

Abstract

Provided by the embodiment of the present invention are a method and device for transmitting a downlink signal, and a method and device for receiving the same. The method for transmitting the downlink signal comprises: receiving, by an access network device, an uplink pilot signal transmitted by a terminal over at least one sub-carrier of a downlink band; obtaining, by the access network device, information on the state of a downlink channel of the downlink band, according to the uplink pilot signal and the channel reciprocity; determining, by the access network device, the transmission strategy of the downlink signal in the downlink band, according to the information on the state of the downlink channel; and transmitting, by the access network device, the downlink signal to the terminal over the downlink band, according to the transmission strategy of the downlink signal. The technical solution of the embodiment of the present invention can be adopted to accurately obtain information on the state the downlink channel of the downlink band with less signal overhead so as to transmit the downlink signal to the terminal by means of the accurate transmission strategy of the downlink signal.

Description

Downlink signal transmission method and device, downlink signal reception method and device

Technical field

The present invention relates to communication technologies, and in particular, to a downlink signal transmission method and apparatus, and a downlink signal reception method and apparatus.

Background technique

The Frequency Division Duplex (FDD) technology is one of the duplex communication technologies used in mobile communication systems. In the FDD system, the base station transmits the downlink signal to the terminal by using the downlink frequency band, and receives the uplink signal sent by the terminal by using the uplink frequency band. In order to obtain channel state information of the downlink frequency band, a terminal feedback mechanism is defined in The 3rd Generation Partnership Project (3GPP). The terminal obtains the state information of the instantaneous channel of the downlink frequency band by measuring the instantaneous channel of the downlink frequency band, and then quantizes the state information and feeds back to the base station.

The applicant finds that the terminal feedback mechanism has the following problems: since the terminal feedbacks the channel state information of the quantized downlink frequency band, if the feedback precision needs to be improved, the feedback signal occupies more uplink resources, thereby affecting the uplink signal transmission; If the uplink resource occupied by the feedback signal is reduced, the feedback accuracy is lowered, thereby affecting the transmission of the downlink signal.

Summary of the invention

The embodiment of the invention provides a method and a device for transmitting a downlink signal, a method and a device for receiving a downlink signal, which are used for solving the contradiction between improving the feedback precision and reducing the uplink resource occupied by the feedback signal.

The first aspect provides a method for transmitting a downlink signal, including: an access network device receiving an uplink pilot signal sent by a terminal on at least one subcarrier of a downlink frequency band; and the access network device according to the uplink pilot signal and The channel reciprocity obtains the status information of the downlink channel on the downlink frequency band; the access network device determines, according to the status information of the downlink channel, a downlink signal transmission policy on the downlink frequency band; the access network device And transmitting, according to the transmission strategy of the downlink signal, the downlink signal to the terminal on the downlink frequency band.

A second aspect provides a method for receiving a downlink signal, including: at least a terminal in a downlink frequency band Sending an uplink pilot signal to the access network device on a subcarrier, where the uplink pilot signal is used by the access network device to acquire a downlink signal transmission policy on the downlink frequency band; the terminal receives the access The downlink signal sent by the network device on the downlink frequency band according to a transmission policy of the downlink signal.

The third aspect provides a downlink signal sending apparatus, including: a receiving unit, configured to receive an uplink pilot signal sent by a terminal on at least one subcarrier of a downlink frequency band; and a processing unit, configured to use, according to the uplink pilot signal, The channel reciprocity obtains the state information of the downlink channel of the downlink frequency band, and the transmission policy for determining the downlink signal on the downlink frequency band according to the state information of the downlink channel, and the sending unit, configured to use, according to the downlink signal The sending policy sends the downlink signal to the terminal on the downlink frequency band.

A fourth aspect provides a receiving apparatus for a downlink signal, including: a sending unit, configured to send, by using an uplink pilot signal, an uplink pilot signal to the access network device on at least one subcarrier of a downlink frequency band, where the uplink pilot signal is used for the And the receiving unit is configured to receive the downlink signal that is sent by the access network device on the downlink frequency band according to the sending policy of the downlink signal.

In the embodiment of the present invention, the access network device receives the uplink pilot signal sent by the terminal on at least one subcarrier of the downlink frequency band, determines the transmission strategy of the downlink signal according to the uplink pilot signal and the channel reciprocity, and performs the downlink signal on the downlink frequency band. The terminal sends a downlink signal. The access network device does not need the terminal to feed back the channel state information of the quantized downlink frequency band, thereby avoiding the problem that the feedback signal occupies more uplink resources. The channel state information of the downlink frequency band acquired by the solution of the embodiment of the present invention is more accurate than the manner of acquiring the channel state information of the downlink frequency band by using the statistical characteristics of the channel.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings to be used in the description of the embodiments of the present invention will be briefly described below. The drawings in the following description are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

1 is a flowchart of a method for transmitting and receiving a downlink signal according to a first embodiment of the present invention;

2 is a schematic diagram of transmitting an uplink pilot signal in a downlink frequency band according to a second embodiment of the present invention;

FIG. 3 is a schematic diagram of a pilot sequence of an uplink pilot signal transmitted on one subcarrier of a downlink frequency band according to a third embodiment of the present invention;

4a to 4c are schematic diagrams showing a pilot sequence of an uplink pilot signal transmitted on one subcarrier of a downlink frequency band according to a fourth embodiment of the present invention;

FIG. 5 is a schematic diagram of a pilot sequence of an uplink pilot signal transmitted on two or more subcarriers in a downlink frequency band according to a fifth embodiment of the present invention;

FIG. 6 is a schematic diagram of a method for transmitting a downlink signal according to a sixth embodiment of the present invention;

FIG. 7 is a schematic diagram of a communication system according to a seventh embodiment of the present invention; FIG.

FIG. 8 is a schematic diagram of a communication system according to an eighth embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

The communication system involved in the embodiment of the present invention may be a second generation (2G) mobile communication system, such as a Global System for Mobile Communications (GSM), or a third generation (The Third) Generation, referred to as 3G) mobile communication system, for example, Universal Mobile Telecommunications System (UMTS), or The Fourth Generation (4G) mobile communication system, for example, Long Term Evolution (Long Term Evolution, Referred to as LTE) system. Optionally, the communication system involved in the embodiment of the present invention may also be a new generation mobile communication system, such as the fifth generation (5G) mobile communication system.

The terminal involved in the embodiment of the present invention may be a wireless terminal, and the wireless terminal may be a device that provides voice or data connectivity to the user, a handheld device with a wireless connection function, or other processing device connected to the wireless modem. The wireless terminal can communicate with one or more core networks via a radio access network (for example, a Radio Access Network, RAN for short), and the wireless terminal can be a mobile terminal, such as a mobile phone (or "cellular" phone), or A computer with a mobile terminal, such as a portable, pocket, handheld, computer built-in or in-vehicle mobile device that exchanges voice or data with a wireless access network. For example, the wireless terminal may be a personal communication service (PCS) phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, or an individual. Devices such as the Digital Assistant (PDA). A wireless terminal may also be called a system, a Subscriber Unit, a Subscriber Station, a Mobile Station, a Mobile, a Remote Station, and an Access Point. AP), Remote Terminal, Access Terminal, User Terminal, User Agent, User Device, or User Equipment (UE).

In the embodiment of the present invention, the network side device may include an access network device, for example, may be a base station controller (BSC) in a GSM system or a CDMA system, or may be a radio network controller in a WCDMA system. (Radio Network Controller, RNC for short) may also be a base station device or a centralized server in various communication systems, or may be a combination of a base station device and a controller. It should be noted that, in the GSM system, the base station device may be a Base Transceiver Station (BTS); in the UMTS system, the base station device may be a NodeB; in the LTE system, the base station device may be an evolved base station ( eNodeB). It should be understood that the network side device in the embodiment of the present invention includes the access network device in the existing communication system, and the access network device in the communication system that may occur in the future, which is not limited in the embodiment of the present invention.

In the embodiment of the present invention, the uplink signal refers to a signal sent by the terminal to the network side device (for example, the access network device), and the downlink signal refers to the network side device (for example, the access network device) sends the signal to the terminal. signal. In the embodiment of the present invention, the network side device is used as an access network device for illustration.

FIG. 1 is a flowchart of a method for transmitting and receiving a downlink signal according to a first embodiment of the present invention. As shown in FIG. 1, the method in this embodiment includes:

The terminal sends an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band, and the uplink pilot signal is used by the access network device to obtain a downlink signal transmission strategy on the downlink frequency band.

The subcarriers involved in the embodiments of the present invention refer to radio waves having a certain frequency. Optional, The subcarriers may be subcarriers in the LTE system, but are not limited to subcarriers in the LTE system; the subcarriers may also be carriers of transmitted signals in the GSM system or the UMTS system. Optionally, in the LTE system, the downlink frequency band includes multiple subcarriers, that is, the downlink frequency band corresponds to multiple subcarriers; in the GSM system or the UMTS system, the downlink frequency band includes one carrier, that is, the downlink frequency band corresponds to one carrier.

Optionally, in the GSM system, the uplink pilot signal may be an uplink training sequence; in the UMTS system, the uplink pilot signal may be a pilot; in the LTE system, the uplink pilot signal It can be a Sounding Reference Signal (SRS).

Optionally, when at least one subcarrier is one subcarrier, the terminal sends an uplink pilot signal to the access network device on one subcarrier of the downlink frequency band.

Optionally, the terminal sends a pilot sequence of the uplink pilot signal to the access network device in n time units of one subcarrier, where n is a positive integer. Optionally, a part of the pilot sequence of the uplink pilot signal is sent in each of the n time units, and the pilot sequence sent in the n time units constitutes an uplink pilot sent on the one subcarrier. signal.

Optionally, the terminal sends a pilot sequence of the uplink pilot signal to the access network device in consecutive n time units; or the terminal sends the pilot of the uplink pilot signal to the access network device in the intermittent n time units. sequence.

Optionally, the time unit is a time slot or a symbol time. For example, in a GSM system or a UMTS system, a time unit is a time slot; in an LTE system, a time unit is a symbol time, and a symbol time is a length of time in which a symbol lasts in the time domain. Optionally, in the LTE system, a time-frequency resource corresponding to one symbol time in the time domain is a resource element (Resource Element, RE for short). Optionally, in the LTE system, the terminal sends a pilot sequence of the uplink pilot signal to the access network device in n time units of one subcarrier, that is, the terminal accesses the n REs in one subcarrier. The network device transmits a pilot sequence of the uplink pilot signal.

Optionally, when at least one subcarrier includes more than two subcarriers, the terminal sends a pilot sequence of the uplink pilot signal to the access network device on at least two subcarriers of the downlink frequency band. Optionally, the pilot sequence transmitted on different subcarriers of the two or more subcarriers constitutes an uplink pilot signal sent on the two or more subcarriers. Optionally, different subcarriers of the two or more subcarriers may be continuous or discontinuous in the frequency domain. When different subcarriers of more than two subcarriers are continuous in the frequency domain When different subcarriers have a certain guard interval in the frequency domain, it is advantageous to reduce mutual interference between pilot sequences of uplink pilot signals on different subcarriers. Optionally, the pilot sequences sent on different subcarriers of the two or more subcarriers may be identical, partially identical, or completely different. Optionally, the number of time units for transmitting the pilot sequence on different subcarriers of the two or more subcarriers may be the same, may be partially the same, or may be completely different. Optionally, the time unit for transmitting the pilot sequence on different subcarriers of the two or more subcarriers may be the time unit with the same time domain, that is, the terminal simultaneously connects on different subcarriers of the two or more subcarriers in the downlink frequency band. The pilot sequence of the uplink pilot signal is sent by the network access device; or the time unit for transmitting the pilot sequence on different subcarriers of the two or more subcarriers may also be a time unit with different time domains, that is, the terminal is in the downlink frequency band. A pilot sequence of an uplink pilot signal is not simultaneously transmitted to different access network devices on different subcarriers of two or more subcarriers.

Optionally, the terminal filters the uplink pilot signal, and the terminal sends the filtered uplink pilot signal to the access network device on at least one subcarrier of the downlink frequency band. For example, a finite-length impulse response (FIR) digital filter or an Infinite Impulse Response (IIR) digital filter can be used to filter the uplink pilot signal, thereby suppressing the uplink. The interference of the uplink pilot signal to the downlink signal to be received by the terminal after the transmission period during the frequency signal transmission period.

102. The access network device receives an uplink pilot signal sent by the terminal on at least one subcarrier of the downlink frequency band.

In this step, the content similar to that in step 101 can be referred to the detailed description in step 101, and details are not described herein again.

Optionally, the access network device receives the uplink pilot signal sent by the terminal on at least one subcarrier of the downlink frequency band.

Optionally, when at least one subcarrier is one subcarrier, the access network device receives an uplink pilot signal sent by the terminal on one subcarrier of the downlink frequency band.

Optionally, the access network device receives a pilot sequence of the uplink pilot signal sent by the terminal in n time units of one subcarrier.

Optionally, the access network device receives a pilot sequence of the uplink pilot signal sent by the terminal in consecutive n time units; or the access network device receives the uplink pilot sent by the terminal in the intermittent n time units. The pilot sequence of the signal.

Optionally, in the LTE system, the access network device receives a pilot sequence of the uplink pilot signal sent by the terminal on the n REs in one subcarrier.

Optionally, when the at least one subcarrier includes more than two subcarriers, the access network device receives a pilot sequence of the uplink pilot signal sent by the terminal on the two or more subcarriers in the downlink frequency band. Optionally, the time unit for transmitting the pilot sequence on different subcarriers of the two or more subcarriers may be the time unit with the same time domain, that is, the access network device receiving terminal simultaneously transmits on the two or more subcarriers in the downlink frequency band. The pilot sequence of the uplink pilot signal; or the time unit for transmitting the pilot sequence on different subcarriers of the two or more subcarriers may also be a time unit in which the time domain is not completely the same, that is, the access network device receiving terminal is in the downlink A pilot sequence of uplink pilot signals that are not simultaneously transmitted on more than two subcarriers of the frequency band.

103. The access network device acquires state information of the downlink channel of the downlink frequency band according to the uplink pilot signal and the channel reciprocity.

The channel reciprocity in the embodiment of the present invention means that when the uplink signal and the downlink signal are transmitted in the same frequency band, the fading of the uplink instantaneous channel and the downlink instantaneous channel may be considered to be substantially the same, that is, the uplink instantaneous channel and the downlink instantaneous channel. Has channel reciprocity. In this embodiment and subsequent embodiments, the uplink instantaneous channel in the downlink frequency band may also be referred to as an uplink channel, and the downlink instantaneous channel in the downlink frequency band may also be referred to as a downlink channel.

Optionally, the status information of the downlink channel includes at least one of a channel quality indicator (CQI), a channel coefficient, and a rank of the channel. The rank of the channel may also be referred to as the degree of freedom of the channel. Optionally, the channel coefficients include quantized channel coefficients or unquantized channel coefficients.

Optionally, when at least one subcarrier is one subcarrier, the access network device acquires the downlink frequency band according to the pilot sequence and channel reciprocity of the uplink pilot signal sent by the terminal in n time units of one subcarrier. Status information of the downlink channel.

Optionally, the access network device acquires state information of the downlink channel of the downlink frequency band according to the pilot sequence and the channel reciprocity of the uplink pilot signal sent by the terminal on the partial subcarriers of the two or more subcarriers. For example, the access network device may obtain the state information of the downlink channel of the downlink frequency band according to the pilot sequence and channel reciprocity of the uplink pilot signal sent by the terminal on one of the two or more subcarriers; the access network device Uplink pilots may also be sent according to the terminal transmitting on multiple subcarriers (for example, two subcarriers, or three subcarriers, or three or more subcarriers) of two or more subcarriers. The pilot sequence of the signal and the channel reciprocity obtain state information of the downlink channel of the downlink frequency band. Optionally, the access network device acquires state information of the downlink channel of the downlink frequency band according to the pilot sequence and the channel reciprocity of the uplink pilot signal sent by the terminal on all the subcarriers of the two or more subcarriers.

Optionally, the access network device acquires state information of the uplink channel of the downlink frequency band according to the uplink pilot signal; the access network device acquires state information of the downlink channel according to the state information of the uplink channel and the channel reciprocity. For example, the access network device uses the status information of the uplink channel as the status information of the downlink channel according to the channel reciprocity; or the access network device processes the status information of the uplink channel, and after processing according to the channel reciprocity, The status information of the uplink channel is used as status information of the downlink channel. Optionally, the processing performed by the access network device on the status information of the uplink channel may be a smooth filtering process or a weighting process, and the embodiment does not limit the specific implementation of the state information of the uplink channel by the access network device. the way.

Optionally, the access network device performs interference cancellation on the uplink pilot signal; the access network device acquires state information of the downlink channel in the downlink frequency band according to the uplink pilot signal and the channel reciprocity after the interference cancellation. For example, the interference cancellation (Interference Cancellation, IC for short) can be used to cancel the interference of the uplink pilot signal, so that the access network device can transmit the signal to the receiving uplink pilot before receiving the uplink pilot signal. Signal interference. Among them, interference cancellation can also be called interference cancellation.

104. The access network device determines, according to the status information of the downlink channel, a downlink signal transmission policy on the downlink frequency band.

Optionally, the transmission strategy of the downlink signal includes at least one of a transmission weight of the downlink signal, a transmission mode of the downlink signal, and a resource allocation of the downlink signal.

Optionally, the sending weight of the downlink signal includes a single user sending weight or a multi-user sending weight. Optionally, when the downlink is transmitted by multiple antennas, the access network device may perform weighting on the antenna dimensions of different terminals by determining a transmission weight of the downlink signal, so as to suppress interference between the terminals at the transmitting end. At each transmission time, the weighted optimal weight may be determined according to status information of the downlink channel between the access network device and the terminal. Optionally, the transmission mode of the downlink signal includes a transmit diversity transmission mode or a beamforming transmission mode. Optionally, the resource allocation of the downlink signal is determined according to at least one of a signal size, an interference size, a historical rate, and a user priority. Optionally, the signal size or the interference size may be determined according to status information of the downlink channel.

Optionally, the access network device can also directly obtain the uplink pilot signal and channel reciprocity. The transmission strategy of the downlink signal on the line frequency band.

105. The access network device sends a downlink signal to the terminal in a downlink frequency band according to a transmission strategy of the downlink signal.

Optionally, the access network device filters the downlink signal, and the access network device sends the filtered downlink signal to the terminal in the downlink frequency band according to the downlink signal transmission policy. For example, the downlink signal may be filtered by using an FIR digital filter or an IIR digital filter, so that the uplink pilot signal reception period and the interference of the downlink signal to the uplink pilot signal may be suppressed.

Optionally, the downlink signal includes at least one of downlink signaling, downlink data, and downlink reference signal. The downlink reference signal may be used to assist in acquiring state information of the downlink channel in the downlink frequency band.

Optionally, the access network device receives the uplink pilot signal sent by the terminal on the at least one subcarrier of the downlink frequency band in the first time period; and the access network device sends the uplink pilot signal according to the terminal in the first time period. The channel reciprocity obtains the status information of the downlink channel in the downlink time band in the first time period; the access network device obtains the downlink information in the downlink time band in the second time period according to the state information of the downlink channel in the downlink time band in the first time period. The status information of the channel, wherein the second time period is later than the first time period; the access network device determines the downlink signal transmission policy according to the downlink channel state information of the downlink frequency band in the second time period; the access network device is in the The downlink signal is sent to the terminal in the downlink frequency band according to the transmission strategy of the downlink signal in the second time period.

Optionally, the uplink pilot signal and the downlink signal may have a certain guard interval in the time domain, thereby facilitating reducing mutual interference between the uplink pilot signal and the downlink signal.

106. The terminal receives, by the access network device, a downlink signal that is sent on a downlink frequency band according to a transmission strategy of the downlink signal.

In this step, the content similar to that in step 105 can be referred to the detailed description in step 105, and details are not described herein again.

Optionally, the terminal sends an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band in the first time period, where the uplink pilot signal is used by the access network device to obtain a downlink signal transmission strategy on the downlink frequency band. The terminal receives the downlink signal sent by the access network device on the downlink frequency band according to the transmission strategy of the downlink signal in the second time period.

Optionally, in this embodiment and subsequent embodiments, the pilot sequence of the uplink pilot signal includes an orthogonal sequence or a pseudo orthogonal sequence. Optionally, the orthogonal sequence includes an Orthogonal Variable Spreading Factor (OVSF) sequence, Zadev-Zhu At least one of the (Zadoff-Chu, abbreviated as ZC) sequences. Optionally, the pseudo orthogonal sequence comprises at least one of a maximum length linear shift register sequence m sequence, a Golden sequence, and a Walsh sequence.

In this embodiment, the access network device receives the uplink pilot signal sent by the terminal on at least one subcarrier of the downlink frequency band, determines a transmission strategy of the downlink signal according to the uplink pilot signal and channel reciprocity, and provides the terminal to the terminal in the downlink frequency band. Send a downlink signal. The access network device in this embodiment does not need the terminal to feed back the channel state information of the quantized downlink frequency band, thereby avoiding the problem that the feedback signal occupies more uplink resources. The channel state information of the downlink frequency band acquired by the method in this embodiment is more accurate than the manner in which the channel state information of the downlink frequency band is obtained by using the statistical characteristics of the channel.

Further, the terminal may send the uplink pilot signal to the access network device on at least one subcarrier of the downlink frequency band, or even send the uplink pilot signal to the access network device in n time units of one subcarrier of the downlink frequency band. Pilot sequence. Therefore, the method in this embodiment can transmit a pilot sequence of a small number of uplink pilot signals to the access network device by using the terminal in the downlink frequency band, thereby reducing the overhead generated by the access network device by sending a large number of reference signals to the terminal, and occupying Less down resources.

The following is an example of the application scenario of the GSM system or the UMTS system. As described above, in various embodiments applied to the GSM system or the UMTS system, the subcarrier refers to the carrier of the transmitted signal in the GSM system or the UMTS system. In these embodiments, the downlink frequency band includes only one carrier, that is, the downlink frequency band corresponds to one carrier.

FIG. 2 is a schematic diagram of an uplink pilot signal transmitted on a downlink frequency band according to a second embodiment of the present invention. For the same or similar content as the first embodiment, refer to the detailed description in the first embodiment, and details are not described herein again.

In this embodiment, on the uplink frequency band, the base station receives the uplink signal sent by the terminal; in the downlink frequency band, the base station receives the uplink pilot signal sent by the terminal and sends the downlink signal to the terminal. For example, at times t ₁ to t ₂ and t ₃ to t ₄ , the terminal transmits an uplink pilot signal to the access network device on the downlink frequency band, and correspondingly, the access network device is at t ₁ t t ₂ and t ₃ t t _At time _{4, the} receiving terminal transmits the uplink pilot signal on the downlink frequency band; at time t ₂ to t ₃ and t ₄ to t ₅ , the access network device sends the downlink signal to the terminal in the downlink frequency band, correspondingly, the terminal is at t ₂ ~ t ₃ and time t ₄ ~ t ₅ receives access network device transmits a downlink signal in the downlink frequency band. Optionally, the access network device obtains, according to the uplink pilot signal sent by the terminal at time t ₁ to t ₂ and the channel reciprocity, state information of the downlink channel in the downlink frequency band from t ₁ to t ₂ . Optionally, the access network device acquires state information of the downlink channel in the downlink frequency band from t ₂ to t ₃ according to the state information of the downlink channel in the downlink frequency band at times t ₁ to t ₂ . Alternatively, the access network device determines downlink signal transmission policy at t ₂ ~ t ₃ time t in the downlink band downlink channel ₂ ~ t ₃ time status information. Optionally, the terminal sends an uplink pilot signal to the access network device in the downlink frequency band from time t ₁ to time t ₂ , and the terminal receives the access network device according to the downlink signal transmission policy on the downlink frequency band at time t ₂ to t ₃ . The downlink signal sent.

It should be noted that the labeling of the uplink pilot signal in FIG. 2 does not mean that all signals transmitted during the time period are all uplink pilot signals. Optionally, between t ₁ and t ₂ or between t ₃ and t ₄ , the transmitted signals may all be uplink pilot signals, or may be part of an uplink pilot signal, and the other part is a downlink signal. See the third embodiment, and details are not described herein again.

On the basis of the second embodiment, FIG. 3 is a schematic diagram of a pilot sequence of an uplink pilot signal transmitted on one subcarrier of a downlink frequency band according to a third embodiment of the present invention. In Figures 3a to 3c, the upstream band is not shown. For the same or similar content in the first embodiment and the second embodiment, reference may be made to the detailed description in the first and second embodiments, and details are not described herein again.

In this embodiment, the time period (for example, t ₃ to t ₄ time period) for transmitting the uplink pilot signal includes 15 time units, and 5 time units are used for transmitting the pilot sequence as an example for description. Optionally, in this embodiment, the time unit is a time slot. Optionally, in the UMTS system, the 15 time units are 15 time slots, and the 15 time slots constitute one frame. The five time units may be any five of the 15 time units. For example, as shown in FIG. 3a, the five time units are consecutive five time units; as shown in FIG. 3b, the five time units are partially consecutive 5 time units; as shown in FIG. 3c, the five The time unit is 5 time units that are completely discontinuous.

The LTE system is used as an application scenario for example. As described above, in various embodiments applied to the LTE system, the downlink frequency band includes multiple subcarriers, that is, the downlink frequency band corresponds to multiple subcarriers in the LTE system.

When the terminal transmits the uplink pilot signal on one of the plurality of subcarriers in the downlink frequency band, the method for transmitting the uplink pilot signal on the downlink frequency band is similar to the method in the second or third embodiment. An example will be described below in conjunction with Figures 4a to 4c. 4a to 4c are schematic diagrams showing a pilot sequence of an uplink pilot signal transmitted on one subcarrier of a downlink frequency band according to a fourth embodiment of the present invention. In Figures 4a to 4c, the upstream band is not shown. In this embodiment, the same or similar content as the first to third embodiments can be referred to the detailed description in the first to third embodiments, and details are not described herein again.

Alternatively, in the present embodiment, FIGS. 4a to 4c illustrate an uplink pilot signal transmission between a time period (e.g., t ₃ ~ t ₄ time period) within a downlink frequency band. In this embodiment, the following frequency band includes 12 subcarriers, and the time period for transmitting the uplink pilot signal includes 14 time units, and 5 time units are used for transmitting the pilot sequence as an example for description. In this embodiment, one subcarrier that transmits the uplink pilot signal may be any one of the 12 subcarriers. The five time units may be any five of the 14 time units. For example, as shown in FIG. 4a, the five time units are consecutive five time units; as shown in FIG. 4b, the five time units are partially consecutive five time units; as shown in FIG. 4c, the five The time unit is 5 time units that are completely discontinuous.

Optionally, the time unit is a symbol time. In the LTE system, one frequency carrier corresponds to one subcarrier, and the time-frequency resource corresponding to one symbol time in the time domain is RE. 4a to 4c show two Resource Blocks (RBs) in an LTE system, where one RB corresponds to 12 subcarriers in the frequency domain and 7 symbol times in the time domain. In an LTE system, two RBs constitute one RB Pair.

FIG. 5 is a schematic diagram of a pilot sequence of an uplink pilot signal transmitted on two or more subcarriers in a downlink frequency band according to a fifth embodiment of the present invention. In Figures 5a to 5j, the upstream frequency band is not shown. In the present embodiment, the same or similar contents as the first to fourth embodiments can be referred to the detailed description in the first to fourth embodiments, and details are not described herein again.

5a-5j illustrate transmitting uplink pilot signals for a time period (e.g., t ₃ ~ t ₄ time period) within a downlink frequency band. In this embodiment, the following frequency band includes 12 subcarriers, and the number of subcarriers used for transmitting the pilot sequence of the uplink pilot signal is 5. For convenience of description, the five subcarriers may be labeled as subcarrier A, subcarrier B, subcarrier C, subcarrier D, and subcarrier E. In this embodiment, the five subcarriers may be any five subcarriers in the downlink frequency band. For example, as shown in FIG. 5b, FIG. 5e, and FIG. 5h, the five subcarriers may be five subcarriers that are consecutive in the frequency domain in the downlink frequency band; as shown in FIG. 5c, FIG. 5f, and FIG. 5i, the five subcarriers are also The five subcarriers that are partially contiguous in the frequency domain in the downlink frequency band, as shown in FIG. 5d, FIG. 5g, and FIG. 5j, may also be five subcarriers in the downlink frequency band that are completely discontinuous in the frequency domain.

The number of time units for transmitting pilot sequences on each of the five subcarriers may be identical, partially identical, or completely different. For example, as shown in FIG. 5b to FIG. 5j, the number of time units for transmitting a pilot sequence on each of the five subcarriers is the same; as shown in FIG. 5a, pilots are transmitted on each of the five subcarriers. The number of time units of the sequence is partially the same.

The number of time units for transmitting a pilot sequence on each of the five subcarriers may be one. It can also be multiple (for example, two, three or more). For example, as shown in FIG. 5a, the number of time units for transmitting a pilot sequence on subcarrier E is one, and the number of time units for transmitting a pilot sequence on subcarrier A to subcarrier D is plural.

When the time unit of transmitting the pilot sequence on one of the five subcarriers is a plurality of time units, the plurality of time units may be consecutive multiple time units, or may be intermittent multiple time units. For example, as shown in FIG. 5a, a plurality of time units in which a pilot sequence is transmitted in subcarrier C is a plurality of consecutive time units, and a plurality of time units of a pilot sequence are transmitted in subcarrier A, subcarrier B, and subcarrier D. Multiple time units that are intermittent. The method of transmitting the pilot sequence on one subcarrier is similar to the method in the second to fourth embodiments, and details are not described herein again.

The time unit for transmitting the pilot sequence on each of the five subcarriers may be the same time unit in the time domain, or may be a time unit with different time domains. For example, as shown in FIG. 5b to FIG. 5d, the five time units of the pilot sequence transmitted on the subcarrier A to the subcarrier E are the same five time units in the time domain, that is, the terminal accesses the access network on the five subcarriers. The device simultaneously transmits a pilot sequence of the uplink pilot signal, and correspondingly, the access network device receives the pilot sequence of the uplink pilot signal that the terminal simultaneously transmits on the five subcarriers; as shown in FIG. 5e to FIG. 5j, the subcarrier The five time units of the pilot sequence transmitted from A to subcarrier E are five time units with different time domains, that is, the pilot sequence of the uplink pilot signal is not simultaneously transmitted by the terminal to the access network device on the five subcarriers. Correspondingly, the access network device receives a pilot sequence of the uplink pilot signal that the terminal does not simultaneously transmit on the five subcarriers.

FIG. 6 is a schematic diagram of a method for transmitting a downlink signal according to a sixth embodiment of the present invention. This embodiment describes a multi-antenna processing flow in an LTE system as an example. In this embodiment, the access network device may be an eNodeB in the LTE system. As shown in FIG. 6, after the downlink signal is subjected to channel coding, scrambling, modulation, and codeword to layer mapping, the eNodeB is further determined according to the foregoing embodiments. The downlink signal transmission strategy processes the downlink signal in a pre-coding module, and then transmits the processed downlink signal to the terminal. Optionally, the transmission strategy of the downlink signal includes at least one of a transmission weight of the downlink signal, a transmission mode of the downlink signal, and a resource allocation of the downlink signal. This embodiment will be described below by taking the transmission weight of the following line signals as an example.

The precoding module modulates the data that needs to be sent to different terminals to different transmitting antennas according to the weight of the transmission of the downlink signal by the weighting of the antenna dimension. Assuming that the eNodeB has M transmit antennas, a total of N terminals are scheduled, where M and N are integers greater than one. In this embodiment, each terminal has one receiving antenna as an example. The case where each terminal has multiple receiving antennas can be analogized according to the description in this embodiment. The mth antenna represents a certain transmit antenna of the eNodeB, where 1 ≤ m ≤ M and m is an integer. The nth terminal represents one of the N terminals, where 1≤n≤N and n is an integer. s _n represents the downlink signal sent by the eNodeB that the nth terminal needs to receive. w _mn represents the transmission weight of the mth antenna transmitting the downlink signal to the nth terminal, and w _n represents the total transmission weight of the eNodeB transmitting the downlink signal to the nth terminal, where w _n =(w _1n , w _2n ,...,w _mn ,...,w _Mn ). x _n represents the downlink signal sent by the eNodeB to the nth terminal, and x represents the total downlink signal sent by the eNodeB to the N terminals, where x={x ₁ , x ₂ , . . . , x _n , . x _N }. h _i represents state information of a downlink channel between the eNodeB and the i th terminal, where 1 ≤ i ≤ N and i is an integer. y _i represents the downlink signal received by the ith terminal. then

The downlink signal sent by the eNodeB to the nth terminal:

x _n =(w _1n s _n ,w _2n s _n ,...,w _mn s _n ,...,w _Mn s _n )=w _n s _n

The total downlink signal sent by the eNodeB to N terminals:

When calculating the downlink signal received by the ith terminal, that is, n=i, the downlink signal received by the ith terminal:

Therefore, in order to make each of the N terminals receive as many downlink signals as possible, the eNodeB needs to determine w ₁ , w ₂ , according to the values of h ₁ , h ₂ , . . . , h _N . ., the value of w _N , so that for any ith terminal, the value of h _i ·w _i ·s _i is as large as possible, at the same time

The value is as small as possible. Optionally, the eNodeB may obtain status information of the downlink channel according to the method in the foregoing embodiments to determine the downlink signal transmission weight in this embodiment.

FIG. 7 is a schematic diagram of a communication system according to a seventh embodiment of the present invention. For the content of the first embodiment to the sixth embodiment, reference may be made to the detailed description in the first embodiment, and details are not described herein again. As shown in FIG. 7, the communication system provided in this embodiment includes a downlink signal transmitting apparatus 700 and a downlink signal receiving apparatus 710, wherein the downlink signal transmitting apparatus 700 and the downlink signal receiving apparatus 710 communicate with each other.

In this embodiment, the downlink signal sending apparatus 700 may be an access network device, for example, various Base station equipment in a communication system. For example, in the GSM system, the base station device can be a BTS; in the UMTS system, the base station device can be a NodeB; in the LTE system, the base station device can be an eNodeB. The receiving device 710 of the downlink signal may be a terminal, such as a UE.

In this embodiment, the sending device 700 of the following line signal is the access network device 700, and the receiving device 710 of the downlink signal is the terminal 710, which is illustrated by way of example.

As shown in FIG. 7, in the embodiment, the access network device 700 includes: a receiving unit 701, a processing unit 702, and a sending unit 703. The terminal 710 includes a transmitting unit 711 and a receiving unit 712. Optionally, the terminal 710 further includes a processing unit 712.

The sending unit 711 of the terminal 710 is configured to send an uplink pilot signal to the access network device 700 on at least one subcarrier of the downlink frequency band, where the uplink pilot signal is used by the access network device 700 to obtain a transmission strategy of the downlink signal.

Optionally, the sending unit 711 is specifically configured to send an uplink pilot signal to the access network device 700 on one subcarrier of the downlink frequency band.

Optionally, the sending unit 711 is specifically configured to send a pilot sequence of the uplink pilot signal to the access network device 700 in n time units of one subcarrier of the downlink frequency band.

Optionally, the sending unit 711 is specifically configured to send a pilot sequence of the uplink pilot signal to the access network device 700 in consecutive n time units or specifically, to send to the access network device 700 in the intermittent n time units. The pilot sequence of the uplink pilot signal.

Optionally, the time unit is a time slot or a symbol time. For example, in an LTE system, the time unit is symbol time. The sending unit 711 is specifically configured to send, in the LTE system, a pilot sequence of the uplink pilot signal to the access network device 700 on the n REs in one subcarrier.

Optionally, the sending unit 711 is specifically configured to send a pilot sequence of the uplink pilot signal to the access network device 700 on the two or more subcarriers of the downlink frequency band. Optionally, the sending unit 711 is specifically configured to send a pilot sequence of the uplink pilot signal to the access network device 700 on two or more consecutive sub-carriers in the frequency domain of the downlink frequency band; or, the sending unit 711 is specifically configured to be used in the downlink. The pilot sequence of the uplink pilot signal is transmitted to the access network device 700 on more than two subcarriers in the frequency domain of the frequency band. Optionally, the sending unit 711 is specifically configured to send the identical pilot sequence to the access network device 700 on different ones of the two or more subcarriers; or, the sending unit 711 is specifically configured to use the two or more subcarriers. Sending a part of the same pilot sequence to the access network device 700 on different subcarriers; or, the sending unit 711 is specifically configured to use different subcarriers of the two or more subcarriers. A completely different pilot sequence is transmitted to the access network device 700 on the wave. Optionally, the sending unit 711 is specifically configured to send, by using the same number of time units of different subcarriers of the two or more subcarriers, a pilot sequence of the uplink pilot signal to the access network device 700; or, the sending unit 711 is specifically used. A pilot sequence of an uplink pilot signal is transmitted to the access network device 700 in a different number of time units of different subcarriers in more than two subcarriers. Optionally, the sending unit 711 is specifically configured to send a pilot sequence of the uplink pilot signal to the access network device 700 in a time unit in which the time domains of different subcarriers of the two or more subcarriers are identical, that is, the sending unit 711 is specifically used. The pilot sequence of the uplink pilot signal is simultaneously sent to the access network device 700 on different subcarriers of the two or more subcarriers; or the sending unit 711 is specifically configured to use the time domain of different subcarriers in the two or more subcarriers. The pilot sequence of the uplink pilot signal is sent to the access network device 700 in a different time unit, that is, the sending unit 711 is specifically configured to send the uplink to the access network device 700 non-simultaneously on different subcarriers of the two or more subcarriers. The pilot sequence of the pilot signal.

Optionally, the sending unit 711 is specifically configured to: after the processor 713 of the terminal 710 filters the uplink pilot signal, send the filtered uplink pilot signal to the access network device 700 on at least one subcarrier of the downlink frequency band.

Optionally, the sending unit 711 is specifically configured to send the uplink pilot signal to the access network device 700 on the at least one subcarrier of the downlink frequency band in the first time period.

The receiving unit 701 of the access network device 700 is configured to receive the uplink pilot signal after the terminal 710 transmits the uplink pilot signal on at least one subcarrier of the downlink frequency band.

Optionally, the receiving unit 701 is specifically configured to receive, by the terminal 710, an uplink pilot signal that is sent on one subcarrier of the downlink frequency band.

Optionally, the receiving unit 701 is specifically configured to receive, by the terminal 710, a pilot sequence of an uplink pilot signal that is sent in n time units of one subcarrier of the downlink frequency band.

Optionally, the receiving unit 701 is specifically configured to receive a pilot sequence of an uplink pilot signal sent by the terminal 710 in consecutive n time units or an uplink guide specifically used by the receiving terminal 710 to send in intermittent n time units. The pilot sequence of the frequency signal.

Optionally, the time unit is a time slot or a symbol time. For example, in an LTE system, the time unit is symbol time. The receiving unit 701 is specifically configured to receive, in the LTE system, a pilot sequence of the uplink pilot signal sent by the terminal 710 on the n REs in one subcarrier.

Optionally, the receiving unit 701 is specifically configured to receive, by the terminal 710, two or more downlink frequency bands. A pilot sequence of uplink pilot signals transmitted on subcarriers. Optionally, the receiving unit 701 is specifically configured to receive a pilot sequence of the uplink pilot signal that is sent by the terminal 710 on the two or more subcarriers in the frequency domain of the downlink frequency band; or the receiving unit 701 is specifically configured to receive the terminal 710. A pilot sequence of uplink pilot signals transmitted on more than two subcarriers in the frequency domain of the downlink frequency band. Optionally, the receiving unit 701 is specifically configured to receive the exactly the same pilot sequence that the terminal 710 sends on different ones of the two or more subcarriers; or the receiving unit 701 is specifically configured to receive the terminal 710 in two or more sub-carriers. A partially identical pilot sequence transmitted on different subcarriers in a carrier; or, the receiving unit 701 is specifically configured to receive a completely different pilot sequence transmitted by the terminal 710 on different ones of the two or more subcarriers. Optionally, the receiving unit 701 is specifically configured to receive a pilot sequence of the uplink pilot signal sent by the terminal 710 in the same number of time units of different subcarriers of the two or more subcarriers; or, the receiving unit 701 is specifically used to The pilot sequence of the uplink pilot signal transmitted by the receiving terminal 710 in a different number of time units of different subcarriers of the two or more subcarriers. Optionally, the receiving unit 701 is specifically configured to receive, by the receiving unit 710, a pilot sequence of the uplink pilot signal that is sent in a time unit in which the time zones of different subcarriers of the two or more subcarriers are identical, that is, the receiving unit 701 is specifically used to a pilot sequence of the uplink pilot signal that is simultaneously transmitted by the receiving terminal 710 on different subcarriers of the two or more subcarriers; or the receiving unit 701 is specifically configured to receive the time domain of the terminal 710 in different subcarriers of the two or more subcarriers. The pilot sequence of the uplink pilot signal transmitted in the time unit that is not identical, that is, the receiving unit 701 is specifically configured to receive the pilot of the uplink pilot signal that is not simultaneously transmitted by the terminal 710 on different subcarriers of the two or more subcarriers. sequence.

Optionally, the receiving unit 701 is specifically configured to: after the sending unit 711 of the terminal 710 sends the filtered uplink pilot signal to the access network device 700 on the at least one subcarrier of the downlink frequency band, receive the filtered uplink pilot. signal.

Optionally, the receiving unit 701 is specifically configured to: when the terminal 710 sends the uplink pilot signal on the at least one subcarrier of the downlink frequency band in the first time period, receive the uplink pilot signal in the first time period.

The processing unit 702 of the access network device 700 is configured to: after the receiving unit 701 receives the uplink pilot signal sent by the terminal 710 on the at least one subcarrier of the downlink frequency band, acquire the downlink frequency band according to the uplink pilot signal and the channel reciprocity. Status information of the downlink channel; and a transmission strategy for determining a downlink signal on the downlink frequency band according to status information of the downlink channel.

Optionally, the processing unit 702 is specifically configured to obtain, according to a pilot sequence and a channel reciprocity of the uplink pilot signal sent by the terminal 710 in the n time units of one subcarrier, state information of the downlink channel in the downlink frequency band. For example, the processing unit 702 is specifically configured to acquire, according to a pilot sequence and channel reciprocity of the uplink pilot signal sent by the terminal 710 in consecutive n time units, status information of the downlink channel of the downlink frequency band; or, the processing unit 702 is specific. For obtaining the state information of the downlink channel of the downlink frequency band according to the pilot sequence and the channel reciprocity of the uplink pilot signal transmitted by the terminal 710 in the n time units of the discontinuity of one subcarrier.

Optionally, the processing unit 702 is specifically configured to obtain, according to a pilot sequence and a channel reciprocity of the uplink pilot signal sent by the terminal 710 on the partial subcarriers of the two or more subcarriers, state information of the downlink channel of the downlink frequency band. For example, the processing unit 702 is specifically configured to acquire state information of a downlink channel of a downlink frequency band according to a pilot sequence and channel reciprocity of the uplink pilot signal sent by the terminal 710 on one of the two or more subcarriers; or The processing unit 702 is specifically configured to: according to the pilot of the uplink pilot signal sent by the terminal 710 on multiple subcarriers (for example, two subcarriers, or three subcarriers, or three or more subcarriers) of two or more subcarriers. The sequence and channel reciprocity obtain state information of the downlink channel of the downlink frequency band. Optionally, the processing unit 702 is specifically configured to obtain, according to a pilot sequence and a channel reciprocity of the uplink pilot signal sent by the terminal 710 on all of the two or more subcarriers, status information of the downlink channel of the downlink frequency band.

Optionally, the processing unit 702 is specifically configured to acquire state information of an uplink channel of the downlink frequency band according to the uplink pilot signal, and specifically, to obtain state information of the downlink channel according to the state information of the uplink channel and the channel reciprocity. For example, the processing unit 702 is specifically configured to use the status information of the uplink channel as the status information of the downlink channel according to the channel reciprocity; or the processing unit 702 is specifically configured to process the status information of the uplink channel according to the channel reciprocity. The processed uplink channel state information is used as state information of the downlink channel. Optionally, the processing unit 702 is specifically configured to perform smoothing processing or weighting processing or other manners on the status information of the uplink channel.

Optionally, the processing unit 702 is specifically configured to perform interference cancellation on the uplink pilot signal, and specifically, to obtain state information of the downlink channel in the downlink frequency band according to the uplink pilot signal and the channel reciprocity after the interference cancellation. For example, the processing unit 702 is specifically configured to perform interference cancellation on the uplink pilot signal by using interference cancellation, so that the receiving unit 701 can be eliminated from receiving the uplink. Before the frequency signal, the transmitting unit 703 transmits the interference of the downlink signal to the receiving unit 701 to receive the uplink pilot signal.

Optionally, the processing unit 702 is specifically configured to: when determining the transmission weight of the downlink signal, perform weighting on different antennas 710 in the antenna dimension, so as to suppress the difference between the different terminals 710 at the transmitting end. interference. Optionally, the processing unit 702 is specifically configured to determine an optimal weight for each transmission time weight according to status information of the downlink channel between the access network device 700 and the terminal 710. Optionally, the processing unit 702 is specifically configured to determine downlink signal resource allocation according to at least one of a signal size, an interference size, a historical rate, and a user priority. Optionally, the processing unit 702 is specifically configured to determine a signal size or a interference size according to the downlink channel state information.

Optionally, the processing unit 702 is specifically configured to filter the downlink signal. For example, the processing unit 702 is specifically configured to filter the downlink signal by using an FIR digital filter or an IIR digital filter, so as to suppress interference of the uplink pilot signal receiving period and the downlink signal to the uplink pilot signal.

Optionally, the processing unit 702 is specifically configured to: after receiving, by the receiving unit 701, the uplink pilot signal sent by the terminal 710 on the at least one subcarrier of the downlink frequency band in the first time period, according to the uplink pilot signal and channel reciprocity Obtaining state information of the downlink channel in the downlink time band in the first time period; and acquiring, according to the state information of the downlink channel in the downlink time band, the state information of the downlink channel in the downlink time band in the second time period And a transmission strategy specifically for determining a downlink signal according to status information of the downlink channel in the downlink time band in the second time period.

The sending unit 703 of the access network device 700 is configured to: after the processing unit 702 determines the sending policy of the downlink signal in the downlink frequency band according to the state information of the downlink channel, send the downlink signal to the terminal 710 according to the sending policy of the downlink signal in the downlink frequency band. .

Optionally, the sending unit 703 is specifically configured to send the filtered downlink signal to the terminal 710 on the downlink frequency band according to the sending policy of the downlink signal.

Optionally, the sending unit 703 is specifically configured to: after the processor 702 determines the sending policy of the downlink signal according to the state information of the downlink channel in the downlink time band in the second time period, according to the sending policy of the downlink signal in the second time period, A downlink signal is transmitted to the terminal 710 on the downlink frequency band.

The receiving unit 712 of the terminal 710 is configured to receive the downlink signal after the downlink signal is sent to the terminal 710 in the downlink frequency band according to the transmission policy of the downlink signal.

Optionally, the receiving unit 712 is specifically configured to: after the sending unit 703 of the access network device 700 sends the filtered downlink signal to the terminal 710 in the downlink frequency band according to the sending policy of the downlink signal, the receiving downlink signal is received.

Optionally, the receiving unit 712 is specifically configured to: when the sending unit 703 of the access network device 700 sends the downlink signal to the terminal 710 in the downlink frequency band according to the sending policy of the downlink signal in the second time period, in the second time period. Receiving the downlink signal.

Optionally, the processing unit 713 of the terminal 710 is configured to filter the uplink pilot signal before the sending unit 711 sends the uplink pilot signal to the access network device 700 on the at least one subcarrier of the downlink frequency band. For example, the processing unit 713 is specifically configured to filter the uplink pilot signal by using an FIR digital filter or an IIR digital filter, so that the uplink pilot signal to the receiving unit 712 after the transmission period can be suppressed in the uplink pilot signal transmission period. The interference of the downlink signal to be received.

Optionally, the processing unit 713 is further configured to: after the receiving unit 712 receives the downlink signal sent by the sending unit 703 of the access network device 700 in the downlink frequency band according to the downlink policy of the downlink signal, perform interference cancellation on the downlink signal.

Optionally, the communication system provided in this embodiment may be a GSM system or a UMTS system, or an LTE system, or may be a 5G mobile communication system or other mobile communication systems that may appear in the future.

Alternatively, the receiving unit 701 and the receiving unit 712 may be receivers, the processing unit 702 and the processing unit 713 may be processors, and the transmitting unit 703 and the transmitting unit 711 may be transmitters.

Optionally, the receiving unit 701 and the sending unit 703 can be combined into a transceiver or a transceiver circuit. The transmitting unit 711 and the receiving unit 712 can also be combined into a transceiver or a transceiver circuit.

Optionally, the receiving unit 701 and the sending unit 703 may be a radio interface of the base station device. Optionally, the radio interface of the base station device may further include an antenna device or a radio interface of the base station device that is connected to the antenna device of the base station device. The transmitting unit 711 and the receiving unit 712 may be wireless interfaces of the terminal. Optionally, the wireless interface of the terminal may further include an antenna device or a wireless interface of the terminal to connect the antenna device of the terminal.

Optionally, the receiving unit 701 in the access network device 700 is configured to perform a signal receiving process of the access network device 700 in the method shown in FIG. 1 to FIG. 5j; the processing unit 702 is configured to perform the operations shown in FIG. 1 to FIG. The signal processing procedure of the access network device 700 in the method; the sending unit 703 can be used to perform the signal transmission process of the access network device 700 in the method shown in FIG. 1 to FIG. The transmitting unit 711 of the terminal 710 is configured to perform the signal sending process of the terminal 710 in the method shown in FIG. 1 to FIG. 5j; the receiving unit 712 of the terminal 710 is configured to perform the signal receiving process of the terminal 710 in the method shown in FIG. 1 to FIG. 5j; The processing unit 713 of the terminal 710 is configured to perform the signal processing procedure of the terminal 710 in the method shown in FIGS. 1 to 5j.

In this implementation, the access network device 700 receives the uplink pilot signal sent by the terminal 710 on at least one subcarrier of the downlink frequency band, determines the transmission strategy of the downlink signal according to the uplink pilot signal and the channel reciprocity, and performs the downlink signal on the downlink frequency band. Terminal 710 transmits a downlink signal. The access network device 700 in this embodiment does not need the terminal 710 to feed back the channel state information of the quantized downlink frequency band, thereby avoiding the problem that the feedback signal occupies more uplink resources. In this embodiment, the channel state information of the downlink frequency band obtained by the access network device 700 according to the uplink pilot signal and the channel reciprocity is more accurate than the channel state information of the downlink frequency band obtained according to the statistical characteristics of the channel. Further, the terminal 710 may send an uplink pilot signal to the access network device 700 on at least one subcarrier of the downlink frequency band, or even send the uplink to the access network device 700 in n time units of one subcarrier of the downlink frequency band. The pilot sequence of the pilot signal can reduce the overhead generated by the access network device 700 transmitting a large number of reference signals to the terminal 710, and occupy less downlink resources.

FIG. 8 is a schematic diagram of a communication system according to an eighth embodiment of the present invention. For the content of the seventh embodiment, reference may be made to the detailed description in the seventh embodiment, and details are not described herein again. As shown in FIG. 8, the communication system provided in this embodiment includes a downlink signal transmitting apparatus 800 and a downlink signal receiving apparatus 810, wherein the downlink signal transmitting apparatus 800 and the downlink signal receiving apparatus 810 communicate with each other. In this embodiment, the transmitting device 800 of the following downlink signal is the access network device 800, and the receiving device 810 of the downlink signal is the terminal 810, which is illustrated by way of example.

As shown in FIG. 8, in this embodiment, the access network device 800 includes a wireless interface 801 and a processor 802.

Optionally, the wireless interface 801 includes the receiving unit 701 and the sending unit 703 in the seventh embodiment. The wireless interface 801 can also include an antenna device or an antenna device that connects the access network device to the wireless interface 801.

Optionally, the processor 802 includes the processing unit 702 in the seventh embodiment.

Further, the access network device 800 may further include a memory 803. Memory 803 is for storing processor executable instructions. The instructions stored in memory 803 may cause processor 802 to perform the process of signal processing described above with respect to Figures 1 through 6, for example:

The processor-executable instructions stored in the memory 803 cause the processor 802 to: obtain an uplink pilot signal sent by the terminal on at least one subcarrier of the downlink frequency band; and acquire a downlink frequency band according to the uplink pilot signal and channel reciprocity Status information of the downlink signal; determining a transmission strategy of the downlink signal in the downlink frequency band according to the state information of the downlink channel; and transmitting the downlink signal to the terminal in the downlink frequency band according to the transmission strategy of the downlink signal.

Optionally, an embodiment of the present invention further provides a computer storage medium or a computer program product for storing the processor executable instructions.

In this embodiment, the terminal 710 includes: a wireless interface 811 and a processor 812.

Optionally, the wireless interface 811 includes a sending unit 711 and a receiving unit 712 in the seventh embodiment. The wireless interface 811 may also include an antenna device or a wireless interface 811 to connect the antenna device of the terminal.

Optionally, the processor 812 includes the processing unit 713 in the seventh embodiment.

Further, the terminal 810 may further include a memory 813. Memory 813 is used to store processor-executable instructions. The instructions stored in memory 813 may cause processor 812 to perform the process of signal processing in Figures 1 through 5j described above, for example:

The processor-executable instructions stored in the memory 813 cause the processor 812 to: transmit an uplink pilot signal to the access network device on at least one subcarrier of the downlink frequency band, and the uplink pilot signal is used by the access network device to obtain the downlink. The downlink signal transmission strategy on the frequency band; the downlink signal sent by the access network device on the downlink frequency band according to the transmission strategy of the downlink signal.

The receiving unit in the embodiments of the present application may directly receive the signal sent by the peer device, or may receive the signal sent by the peer device through other components (for example, an antenna device), and may also receive other component processing (eg, filtering) or The signal sent by the converted peer device.

The sending unit in each embodiment of the present application may directly send a signal to the peer device, or may send a signal to the peer device through other components (for example, an antenna device), and may also send the signal through other components. The number is processed (for example: filtered) or sent to the peer device after conversion.

The processing unit in each embodiment of the present application may directly acquire a signal from the receiving unit, or may indirectly acquire a signal from the receiving unit through an intermediate component (eg, a filter, a coupler). The processing unit may provide signals directly to the transmitting unit, or may indirectly provide signals to the transmitting unit through intermediate elements (eg, filters, couplers).

One of ordinary skill in the art will appreciate that all or part of the steps to implement the various method embodiments described above may be accomplished by hardware associated with the program instructions. The aforementioned program can be stored in a computer readable storage medium. The program, when executed, performs the steps including the foregoing method embodiments; and the foregoing storage medium includes various media that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

A method for transmitting a downlink signal, comprising:

The access network device receives an uplink pilot signal sent by the terminal on at least one subcarrier of the downlink frequency band;

Obtaining, by the access network device, state information of a downlink channel of the downlink frequency band according to the uplink pilot signal and channel reciprocity;

Determining, by the access network device, a transmission strategy of a downlink signal on the downlink frequency band according to status information of the downlink channel;

And the access network device sends the downlink signal to the terminal in the downlink frequency band according to the sending policy of the downlink signal.
The method according to claim 1, wherein said at least one subcarrier is one subcarrier.

The access network device receives an uplink pilot signal that is sent by the terminal on at least one subcarrier of the downlink frequency band, and includes:

The access network device receives the uplink pilot signal sent by the terminal on the one subcarrier.
The method according to claim 1, wherein said at least one subcarrier is one subcarrier.

The access network device receives an uplink pilot signal that is sent by the terminal on at least one subcarrier of the downlink frequency band, and includes:

The access network device receives a pilot sequence of the uplink pilot signal sent by the terminal in n time units of the one subcarrier, where n is a positive integer;

Obtaining, by the access network device, status information of the downlink channel of the downlink frequency band according to the uplink pilot signal and channel reciprocity, including:

The access network device acquires state information of the downlink channel of the downlink frequency band according to the pilot sequence and channel reciprocity of the uplink pilot signal.
The method according to claim 3, wherein the access network device receives a pilot sequence of the uplink pilot signal sent by the terminal in n time units of the one subcarrier, including:

The access network device receives a pilot sequence of the uplink pilot signal sent by the terminal in consecutive n time units or the access network device receives the terminal to send in intermittent n time units The pilot sequence of the uplink pilot signal.
Method according to claim 3 or 4, characterized in that the time unit is a time slot or a symbol time.
The method of claim 1 wherein said at least one subcarrier Includes more than two subcarriers,

The access network device receives an uplink pilot signal that is sent by the terminal on at least one subcarrier of the downlink frequency band, and includes:

Receiving, by the access network device, a pilot sequence of the uplink pilot signal sent by the terminal on the two or more subcarriers;

Obtaining, by the access network device, status information of the downlink channel of the downlink frequency band according to the uplink pilot signal and channel reciprocity, including:

The access network device acquires state information of the downlink channel of the downlink frequency band according to the pilot sequence and channel reciprocity of the uplink pilot signal.
The method according to claim 6, wherein the access network device acquires state information of the downlink channel of the downlink frequency band according to the pilot sequence and the channel reciprocity of the uplink pilot signal, including:

Obtaining, by the access network device, the downlink channel of the downlink frequency band according to a pilot sequence and channel reciprocity of the uplink pilot signal sent by the terminal on a part of the two or more subcarriers status information.
The method according to any one of claims 1 to 7, wherein the access network device acquires state information of the downlink channel of the downlink frequency band according to the uplink pilot signal and channel reciprocity, including :

Obtaining, by the access network device, state information of an uplink channel of the downlink frequency band according to the uplink pilot signal;

The access network device acquires state information of the downlink channel according to state information of the uplink channel and channel reciprocity.
A method according to any one of claims 1 to 7, wherein

Obtaining, by the access network device, status information of the downlink channel of the downlink frequency band according to the uplink pilot signal and channel reciprocity, including:

Obtaining, by the access network device, status information of the downlink channel of the downlink frequency band in the first time period according to the uplink pilot signal and channel reciprocity sent by the terminal in the first time period;

Obtaining, by the access network device, state information of the downlink channel in the downlink frequency band in the second time period according to the state information of the downlink channel in the downlink frequency band in the first time period, where the second time period is late In the first period of time;

Determining, by the access network device, a downlink signal transmission policy on the downlink frequency band according to the status information of the downlink channel, including:

The access network device determines, according to status information of the downlink channel of the downlink frequency band in the second time period, a sending policy of the downlink signal;

Sending, by the access network device, the downlink signal to the terminal in the downlink frequency band according to the sending policy of the downlink signal, including:

The access network device sends the downlink signal to the terminal in the downlink frequency band according to the downlink signal transmission policy in the second time period.
The method according to any one of claims 1 to 9, wherein the transmission strategy of the downlink signal includes a transmission weight of the downlink signal, a transmission mode of the downlink signal, and a resource of the downlink signal. At least one of the assignments.
The method according to any one of claims 3 to 10, characterized in that the pilot sequence of the uplink pilot signal comprises an orthogonal sequence or a pseudo-orthogonal sequence.
A method for receiving a downlink signal, comprising:

The terminal sends an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band, where the uplink pilot signal is used by the access network device to acquire a downlink signal transmission strategy on the downlink frequency band;

Receiving, by the terminal, the downlink signal that is sent by the access network device on the downlink frequency band according to a sending policy of the downlink signal.
The method according to claim 12, wherein said at least one subcarrier is one subcarrier.

The terminal sends an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band, including:

Transmitting, by the terminal, the uplink pilot signal to the access network device on the one subcarrier.
The method according to claim 12, wherein said at least one subcarrier is one subcarrier.

The terminal sends an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band, including:

Transmitting, by the terminal, a pilot sequence of the uplink pilot signal to the access network device in n time units of the one subcarrier, where n is a positive integer.
The method according to claim 14, wherein the terminal transmits the pilot sequence of the uplink pilot signal to the access network device in the n time units of the one subcarrier, including:

Transmitting, by the terminal, a pilot sequence of the uplink pilot signal to the access network device in consecutive n time units or transmitting, by the terminal, the uplink to the access network device in intermittent n time units The pilot sequence of the pilot signal.
Method according to claim 14 or 15, characterized in that the time unit is a time slot or a symbol time.
The method according to claim 12, wherein the at least one subcarrier is more than two subcarriers.

The terminal sends an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band, including:

Transmitting, by the terminal, a pilot sequence of the uplink pilot signal to the access network device on the two or more subcarriers.
A method according to any one of claims 12 to 17, wherein

The terminal sends an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band, including:

Transmitting, by the terminal, the uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band in a first time period;

Receiving, by the terminal, the downlink signal that is sent by the access network device on the downlink frequency band according to the sending policy of the downlink signal, where

Receiving, by the terminal, the downlink signal sent by the access network device on the downlink frequency band according to a sending policy of the downlink signal, where the second time period is later than the first time segment.
The method according to any one of claims 14 to 17, wherein the pilot sequence of the uplink pilot signal comprises an orthogonal sequence or a pseudo orthogonal sequence.
The method according to any one of claims 12 to 19, wherein the transmission strategy of the downlink signal includes a transmission weight of the downlink signal, a transmission mode of the downlink signal, and a resource of the downlink signal. At least one of the assignments.
A device for transmitting a downlink signal, comprising:

a receiving unit, configured to receive an uplink pilot signal sent by the terminal on at least one subcarrier of the downlink frequency band;

a processing unit, configured to acquire state information of a downlink channel of the downlink frequency band according to the uplink pilot signal and channel reciprocity, and configured to determine, according to status information of the downlink channel, a downlink signal on the downlink frequency band Sending strategy;

And a sending unit, configured to send the downlink signal to the terminal on the downlink frequency band according to a sending policy of the downlink signal.
The apparatus according to claim 21, wherein the receiving unit is specifically configured to receive the uplink pilot signal sent by the terminal on one subcarrier of the downlink frequency band.
The apparatus according to claim 21, wherein the receiving unit is specifically configured to receive a pilot of the uplink pilot signal that is sent by the terminal in n time units of one subcarrier of the downlink frequency band. a sequence, wherein n is a positive integer; the processing unit is specifically used Obtaining state information of the downlink channel of the downlink frequency band according to the pilot sequence and the channel reciprocity of the uplink pilot signal.
The apparatus according to claim 23, wherein the receiving unit is specifically configured to receive a pilot sequence of the uplink pilot signal sent by the terminal in consecutive n time units or specifically for receiving The pilot sequence of the uplink pilot signal transmitted by the terminal in the intermittent n time units.
The apparatus according to claim 21, wherein the receiving unit is specifically configured to receive a pilot sequence of the uplink pilot signal sent by the terminal on two or more subcarriers of the downlink frequency band; The processing unit is specifically configured to acquire state information of the downlink channel of the downlink frequency band according to the pilot sequence and channel reciprocity of the uplink pilot signal.
The apparatus according to claim 25, wherein the processing unit is specifically configured to: according to a pilot sequence of the uplink pilot signal sent by the terminal on a part of subcarriers of the two or more subcarriers The channel reciprocity obtains state information of the downlink channel of the downlink frequency band.
The apparatus according to any one of claims 21 to 26, wherein the processing unit is configured to acquire state information of an uplink channel of the downlink frequency band according to the uplink pilot signal, and specifically for The state information of the uplink channel and the channel reciprocity obtain state information of the downlink channel.
The apparatus according to any one of claims 21 to 26, wherein the processing unit is specifically configured to acquire the uplink pilot signal and channel reciprocity transmitted by the terminal in a first time period. The status information of the downlink channel in the downlink frequency band in the first time period, and the information about the downlink frequency channel in the second time period according to the state information of the downlink channel in the downlink time band. The status information of the downlink channel is determined, and the sending policy of the downlink signal is specifically determined according to the status information of the downlink channel in the second time period of the downlink frequency band; the sending unit is specifically configured to be used in the Sending, in the downlink frequency band, the downlink signal to the terminal according to the sending policy of the downlink signal, where the second time period is later than the first time period.
A receiving device for a downlink signal, comprising:

And a sending unit, configured to send an uplink pilot signal to the access network device on the at least one subcarrier of the downlink frequency band, where the uplink pilot signal is used by the access network device to acquire the downlink signal sent on the downlink frequency band Strategy

The receiving unit is configured to receive the downlink signal that is sent by the access network device on the downlink frequency band according to the uplink pilot signal and channel reciprocity.
The apparatus according to claim 29, wherein the sending unit is specifically configured to send the uplink guide to the access network device on one subcarrier of the downlink frequency band. Frequency signal.
The apparatus according to claim 29, wherein the sending unit is configured to: send, in the n time units of one subcarrier of the downlink frequency band, a guide of the uplink pilot signal to the access network device. A frequency sequence in which n is a positive integer.
The apparatus according to claim 31, wherein the sending unit is specifically configured to send a pilot sequence of the uplink pilot signal to the access network device in consecutive n time units or specifically for A pilot sequence of the uplink pilot signal is transmitted to the access network device in n consecutive time units.
The apparatus according to claim 29, wherein the sending unit is configured to send a pilot sequence of the uplink pilot signal to the access network device on two or more subcarriers of the downlink frequency band. .
The apparatus according to any one of claims 29 to 33, wherein the sending unit is configured to send, to the access network device, at least one subcarrier of the downlink frequency band in a first time period. And the receiving unit is configured to receive, in the second time period, the downlink signal that is sent by the access network device on the downlink frequency band according to a sending policy of the downlink signal, where The second time period is later than the first time period.