WO2014169794A1 - Procédé et dispositif de programmation d'émission - Google Patents

Procédé et dispositif de programmation d'émission Download PDF

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Publication number
WO2014169794A1
WO2014169794A1 PCT/CN2014/075235 CN2014075235W WO2014169794A1 WO 2014169794 A1 WO2014169794 A1 WO 2014169794A1 CN 2014075235 W CN2014075235 W CN 2014075235W WO 2014169794 A1 WO2014169794 A1 WO 2014169794A1
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Prior art keywords
scheduling
information
base station
user terminal
transmission
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English (en)
Chinese (zh)
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倪浩
高秋彬
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China Academy of Telecommunications Technology CATT
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China Academy of Telecommunications Technology CATT
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0032—Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
    • H04L5/0035—Resource allocation in a cooperative multipoint environment
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0058—Allocation criteria
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/12—Wireless traffic scheduling

Definitions

  • the present invention relates to the field of wireless communications, and in particular, to a transmission scheduling method and device.
  • Scenery technology relates to the field of wireless communications, and in particular, to a transmission scheduling method and device.
  • Cooperative multipoint transmission technology is the collaboration between multiple geographically separated transmission points (TPs).
  • TPs geographically separated transmission points
  • multiple transmission points refer to base stations of different cells, or a plurality of remote radio heads (RRHs) controlled by a base station of one cell.
  • Cooperative multipoint transmission technology can be divided into downlink cooperative transmission and uplink joint reception. Downlink cooperative transmission is mainly divided into two transmission schemes: coordinated scheduling/coordinated beamforming (CS/CB) and joint processing (JP).
  • CS/CB coordinated scheduling/coordinated beamforming
  • JP joint processing
  • the joint processing scheme can be further divided into joint transmission (JT) and dynamic point selection (DPS) transmission. Multiple transmission points in the JT simultaneously transmit useful signals to the same user terminal, thereby enhancing the reception signal of the user terminal.
  • the transmission point of the user terminal is dynamically switched in the DPS transmission, and the point of the user terminal that is optimal for the user terminal is always selected from the coordinated transmission point.
  • These collaborative multipoint transmission schemes can be used in conjunction with each other.
  • Still In combination with the dynamic blanking (DB) scheme some transmission points can be dynamically set on certain time-frequency resources without transmitting signals.
  • the network configures a measurement set for the user terminal, and the measurement set includes one or more base stations.
  • the network configures one or more channel state information (CSI) processes for the user terminal for each base station in the measurement set.
  • CSI channel state information
  • the user terminal performs CSI reporting according to each CSI process configuration.
  • the base station cooperates according to the CSI report of the user terminal.
  • a large amount of information and data need to be exchanged with each other.
  • backhaul backhaul link
  • Backhaul's information transmission rate and transmission delay are determined by the nature of the backhaul's physical link itself and the protocol stack latency. If the base stations are connected by a large physical link, such as a direct fiber connection, the backhaul has a high information transmission rate (eg, on the order of Gbps). If the base stations are connected by a small physical link, such as a wireless transmission link, the backhaul information transmission rate is low (e.g., 1 Mbps or lower).
  • the backhaul uplink information transmission delay is mainly caused by the physical link transmission delay and the protocol stack delay. Different backhaul transmission delays are different, and usually the non-ideal backhaul transmission delay may reach 10ms or more. There may be multiple backhaul physical connections in the actual network. The information exchange between base stations in CoMP cooperative scheduling should consider non-ideal backhaul.
  • the downlink coordinated multi-point transmission is implemented, and depends on the CSI obtained by the base station to the cooperation points of the cooperation points.
  • the CSI information includes a channel quality indicator (CQI), a recoding matrix indicator (PMI), and a rank indicator (RI).
  • CQI channel quality indicator
  • PMI recoding matrix indicator
  • RI rank indicator
  • the user terminal measures the channel of the base station to the user terminal by using the downlink reference signal sent by each base station, and feeds back the measured channel information to the serving cell (ie, the cell accessed by the user terminal).
  • the serving cell of the user terminal receives the feedback CSI information, and performs cooperative scheduling and/or cooperative precoding with the coordinated cell, which are two types: 1) non-central cooperative scheduling; 2) central cooperative scheduling.
  • Non-central scheduling has no central node for global optimization scheduling.
  • Each coordinated base station transmits the recently received CSI information of all user terminals accessing the base station to a central coordination node (CCN);
  • CCN central coordination node
  • the CCN centrally schedules time domain and frequency domain resources for user terminals of all cooperative base stations, and calculates precoding for user terminals that schedule time-frequency resources;
  • the CCN sends the scheduling and precoding result of each user terminal to each relevant base station; the base station transmits data for the user terminal according to the received resource scheduling and precoding result.
  • the central scheduling method requires the cooperative base station to transmit the CSI information of all the user terminals that are accessed to the CCN, and after the CCN scheduling, all the scheduling results need to be transmitted to the base stations respectively, as shown in FIG. 2 .
  • the scheduling delay (the time interval between each coordinated base station transmitting CSI information to the CCN until receiving the resource scheduling and precoding information transmitted by the CCN) is at least twice the backhaul transmission delay.
  • the scheduling delay in the cooperation set is twice the maximum backhaul transmission delay in the set.
  • the scheduling delay generated by the above-mentioned central scheduling procedure in the case of non-ideal backhaul is approximately 20ms.
  • the existing central scheduling method means that each collaboration point in the collaboration set performs CoMP transmission according to the CSI reported by the user 20ms before.
  • CSI information obsolescence can seriously affect CoMP transmission performance.
  • the impact of CSI information obsolescence on transmission performance mainly includes the following three aspects:
  • the precoding matrix selection is not suitable
  • Precoding matrix selection and link adaptation are more sensitive to CSI information obsolescence in the above three aspects
  • the existing central scheduling method for coordinated multi-point transmission is designed for the ideal backhaul.
  • the accuracy of resource scheduling, precoding matrix selection, and link adaptation will be Affected, thereby affecting CoMP transmission performance.
  • Embodiments of the present invention provide a transmission scheduling method and device for improving CoMP transmission performance.
  • a transmission scheduling method the method comprising:
  • the central cooperative node receives channel information of the user terminal transmitted by each coordinated base station, and performs transmission scheduling according to the channel information of the received user terminal;
  • the central cooperative node obtains scheduling information corresponding to each scheduling resource according to the transmission scheduling result; the central cooperative node sends the scheduling information to the corresponding cooperative base station, so that the cooperative base station according to the recently received channel state information CSI of the user terminal and the scheduling The information determines the data transmission parameters.
  • a transmission scheduling method comprising:
  • the cooperative base station sends the channel information of the user terminal under the cooperative base station to the central cooperative node; the coordinated base station receives the scheduling information sent by the central cooperative node;
  • the cooperative base station determines the data transmission parameter according to the scheduling information sent by the central cooperative node and the channel state information CSI of the recently received user terminal.
  • a central collaboration device includes:
  • a transmission scheduling unit configured to receive channel information of the user terminal sent by each coordinated base station, and perform transmission scheduling according to the received channel information of the user terminal;
  • An information acquiring unit configured to obtain scheduling information corresponding to each scheduling resource according to the transmission scheduling result, where the sending unit is configured to send the scheduling information to the corresponding cooperative base station, so that the cooperative base station according to the channel state information of the recently received user terminal
  • the CSI and the scheduling information determine data transmission parameters.
  • a cooperative base station, the cooperative base station includes:
  • a sending unit configured to send, to the central cooperative node, a channel letter of the user terminal under the cooperative base station Interest rate
  • a receiving unit configured to receive scheduling information sent by the central cooperative node
  • a processing unit configured to determine a data transmission parameter according to the scheduling information sent by the central cooperation node and the channel state information CSI of the recently received user terminal.
  • a central collaboration device comprising: a processor and a memory
  • the memory storing one or more executable programs for configuring the processor; the processor being configured with one or more executable programs, the one or more executable programs for executing The following methods:
  • the scheduling information is sent to the corresponding cooperative base station, so that the cooperative base station determines the data transmission parameter according to the channel state information CSI of the recently received user terminal and the scheduling information.
  • a cooperative base station includes: a processor and a memory
  • the memory storing one or more executable programs for configuring the processor; the processor being configured with one or more executable programs, the one or more executable programs for executing The following methods:
  • the data transmission parameter is determined according to the scheduling information sent by the central coordination node and the channel state information CSI of the recently received user terminal.
  • the central cooperative node performs transmission scheduling according to the channel information of the user terminal sent by each coordinated base station, and obtains scheduling information corresponding to each scheduling resource, and sends the scheduling information to the corresponding coordinated base station, and cooperates.
  • the base station determines the data transmission parameter according to the scheduling information sent by the central cooperative node and the CSI of the recently received user terminal. It can be seen that the coordination node of the solution center only needs to send partial scheduling information to the cooperative base station, and the cooperative base station performs data transmission scheduling and/or determines data transmission parameters according to the partial scheduling information and the latest CSI directly reported by the user terminal.
  • the central cooperative node needs to send all the scheduling information to the cooperative base station, and the user terminal needs to report the CSI to the central cooperative node, and then the central cooperative node forwards the CSI to the cooperative base station, and the cooperative base station performs all the scheduling information and the CSI.
  • this scheme reduces the impact of backhaul delay on CoMP center scheduling, and thus improves CoMP transmission performance.
  • FIG. 1 is a schematic diagram of information interaction of a non-central scheduling in the prior art
  • FIG. 2 is a schematic diagram of information exchange of central scheduling in the prior art
  • FIG. 3 is a schematic flowchart of a method according to an embodiment of the present disclosure.
  • FIG. 5 is a schematic structural diagram of a center collaboration device according to an embodiment of the present disclosure.
  • FIG. 6 is a schematic structural diagram of a cooperative base station according to an embodiment of the present disclosure.
  • FIG. 7 is a schematic structural diagram of a center collaboration device according to another embodiment of the present invention.
  • FIG. 8 is a schematic structural diagram of a base station according to another embodiment of the present invention. detailed description
  • the embodiment of the present invention provides a transmission scheduling method.
  • a transmission scheduling method provided by the embodiment of the present invention for the CCN side includes the following steps. Step:
  • Step 30 The central cooperative node receives channel information of the user terminal sent by the coordinated base station, and performs transmission scheduling according to the received channel information of the user terminal.
  • Step 31 The central cooperative node obtains scheduling information corresponding to each scheduling resource according to the transmission scheduling result.
  • Step 32 The central cooperative node sends the scheduling information to the corresponding cooperative base station, so that the cooperative base station determines the data transmission parameter according to the channel state information CSI of the recently received user terminal and the scheduling information received from the central cooperative node. .
  • the scheduling information may be sent to the cooperative base station when the scheduling information is not empty.
  • the central cooperative node may receive channel information of the user terminal transmitted by the plurality of cooperative base stations; in step 32, when the central cooperative node sends the scheduling information to the cooperative base station The scheduling information determined for the different coordinated base stations may be sent to the corresponding coordinated base station.
  • the channel information of the user terminal sent by the coordinated base station received by the central cooperative node may include channel state information (CSI) reported by the user terminal under the coordinated base station, or may include users according to the coordinated base station.
  • the CSI information statistic obtained by the CSI reported by the terminal for example, the cooperative base station calculates a channel correlation matrix according to a Pre-coding Matrix Indicator (PMI) in the CSI reported by the user terminal multiple times, and uses the channel correlation matrix as a user.
  • the channel information of the terminal is sent to the central cooperative node.
  • PMI Pre-coding Matrix Indicator
  • step 31 can be implemented in one of the following four ways:
  • no coordinated base station is scheduled to be silent on the scheduling resource (so-called “silent", that is, no data is transmitted, "no coordination of any coordinated base station” means that none of the cooperative base stations are
  • the scheduling is silent, that is, each cooperative base station can transmit data, and only the data transmission of the non-CoMP user terminal and/or the non-CoMP data transmission of the CoMP user terminal are scheduled on the scheduling resource, and the scheduling corresponding to the scheduling resource
  • the information is empty, or includes information indicating that the CoMP user terminal is not scheduled, or information including the user terminal scheduled for each coordinated base station on the scheduling resource (for example, identification information of the user terminal).
  • step 32 The specific implementation is as follows: when the scheduling information corresponding to the scheduling resource is empty, the scheduling information corresponding to the scheduling resource is not sent by all the cooperative base stations; and the scheduling information corresponding to the scheduling resource includes information indicating that the CoMP user terminal is not scheduled. And transmitting, to each coordinated base station, information indicating that the CoMP user terminal is not scheduled; and when the scheduling information corresponding to the scheduling resource includes information about the user terminal scheduled for each coordinated base station on the scheduling resource, respectively, sending the scheduling to each coordinated base station.
  • the information on the resource is the information of the user terminal scheduled by the corresponding cooperative base station.
  • the scheduling information corresponding to the scheduling resource includes: performing CS/ to the CoMP user terminal.
  • First scheduling information of the coordinated base station transmitted by the CB, second scheduling information of the base station in the measurement set of the CoMP user terminal, and third scheduling information for other base stations other than the base station in the measurement set of the CoMP user terminal among them:
  • the first scheduling information includes identifier information of the CoMP user terminal and interference state information indicating a coordinated base station that performs interference avoidance for the CS/CB transmission;
  • the second scheduling information includes an available precoding matrix set, and an unavailable precoding matrix At least one of the set, the transmit power constraint information, or at least one of the precoding matrix, the rank information, and the transmit power constraint information used for the transmission;
  • the third scheduling information is empty, or includes information indicating that the CoMP user terminal is not scheduled. Or information including user terminals scheduled for the other base station on the scheduling resource.
  • the first scheduling information may further include: at least one of a precoding matrix, a rank information, a channel quality indicator CQI information, and a modulation and coding information MCS of the scheduled CoMP user terminal.
  • the specific implementation of the step 32 is: sending the first scheduling information to the coordinated base station that performs CS/CB transmission to the CoMP user terminal, and sending the second scheduling information to the cooperative base station in the measurement set of the CoMP user terminal, The third scheduling information is transmitted to other cooperative base stations than the base stations in the measurement set of the CoMP user terminal.
  • the interference state information of the base station refers to information indicating whether the base station interferes with data transmission of the CoMP user terminal.
  • the interference state information of the cooperative base station that is used for the interference avoidance of the CS/CB transmission may be specifically the identification information of the coordinated base station that performs the interference avoidance for the CS/CB transmission or the pre-agreed interference that can be expressed as the CS/CB transmission. Evading the cooperative base station His information.
  • the scheduling resource corresponds to The scheduling information includes: fourth scheduling information for the silent cooperative base station, fifth scheduling information for the cooperative base station performing DPS/DPB transmission to the CoMP user terminal, and DPS/ for the cooperative base station except for the silence and to the CoMP user terminal.
  • the specific implementation in step 32 is: sending the fourth scheduling information to the silent cooperative base station, and sending the fifth scheduling information to the CoMP user.
  • the cooperative base station that performs the DPS/DPB transmission by the terminal transmits the sixth scheduling information to the cooperative base station except the silent cooperative base station and the cooperative base station that performs DPS/DPB transmission to the CoMP user terminal.
  • the scheduling information corresponding to the scheduling resource includes The seventh scheduling information of the coordinated base station other than the coordinated base station that performs the DPS/DPB transmission by the CoMP user terminal; correspondingly, the specific implementation in step 32 is: sending the seventh scheduling information to the cooperative base station except the silent and to the CoMP
  • the other terminal is a cooperative base station other than the cooperative base station in which the user terminal performs DPS/DPB transmission.
  • the fourth scheduling information includes information indicating that the scheduling resource is silent; the fifth scheduling information includes interference state information indicating the silent cooperative base station; the sixth scheduling information is empty, or includes information indicating that the CoMP user terminal is not scheduled. Or including information of user terminals scheduled on the scheduling resource for other coordinated base stations (ie, cooperative base stations other than the silent cooperative base station and the cooperative base station performing DPS/DPB transmission to the CoMP user terminal); The scheduling information is empty, or includes information indicating that the CoMP user terminal is not scheduled, or includes other cooperative base stations on the scheduling resource (ie, other cooperative base stations except DPS/DPB transmission to the CoMP user terminal). Base station) information of the user terminal scheduled.
  • the fifth scheduling information further includes: at least one of the identifier information of the scheduled CoMP user terminal, the precoding matrix of the CoMP user terminal, the rank information, the CQI information, and the MCS.
  • the scheduling information corresponding to the scheduling resource further includes The following additional information of the coordinated base station that performs the DPS/DPB transmission by the CoMP user terminal: the identification information of the scheduled CoMP user terminal, the precoding matrix of the CoMP user terminal, the rank information, the CQI information, and the MCS; corresponding, the step
  • the central coordinating node in 32 also needs to send this additional information to the cooperating base station that performs DPS/DPB transmission to the CoMP user terminal.
  • the interference state information indicating the silent cooperative base station may specifically be the identification information of the silent cooperative base station or other predetermined information of the cooperative base station capable of indicating silence.
  • the scheduling information corresponding to the scheduling resource includes: a cooperative base station for performing JT transmission to the CoMP user terminal.
  • the eighth scheduling information includes: the identification information of the CoMP user terminal and the signal status information of the cooperative base station that performs JT transmission to the CoMP user terminal.
  • the specific implementation in step 32 is: sending the eighth scheduling information to the cooperative base station that performs JT transmission to the CoMP user terminal.
  • the eighth scheduling information further includes: at least one of a precoding matrix, rank information, CQI information, and MCS of the scheduled CoMP user terminal.
  • the signal state information of the base station refers to information indicating whether the base station transmits a useful signal to the CoMP user terminal.
  • the signal state information of the cooperative base station indicating the JT transmission to the CoMP user terminal may specifically be the identification information of the cooperative base station that performs JT transmission to the CoMP user terminal or other predetermined information of the cooperative base station capable of indicating JT transmission to the CoMP user terminal. .
  • the central cooperative node may receive channel information of the user terminal sent by each coordinated base station through a backhaul link, and send scheduling information to the cooperative base station by using backhaul.
  • a transmission scheduling method provided by a coordinated base station side includes the following steps:
  • Step 40 The cooperative base station sends channel information of the user terminal under the cooperative base station to the central cooperative node.
  • Step 41 The cooperative base station receives scheduling information sent by the central cooperative node.
  • Step 42 The cooperative base station determines a data transmission parameter according to the scheduling information sent by the central cooperation node and the CSI of the recently received user terminal.
  • the CSI of the user terminal received by the cooperative base station may be from the user terminal, or may be from other coordinated base stations, that is, the CSI of the user base station may be exchanged between the cooperative base stations.
  • the coordinated base station sends the channel information of the user terminal under the cooperative base station to the central cooperative node, and the specific implementation may be as follows:
  • the cooperative base station receives the CSI reported by the user terminal under the cooperative base station, and reports the CSI as the channel information to the central cooperative node; or the cooperative base station receives the CSI reported by the user terminal under the coordinated base station multiple times, according to the multiple reported
  • the CSI obtains the CSI information statistic, and reports the CSI information statistic as the channel information to the central cooperative node.
  • the cooperative base station sends the channel correlation matrix as the channel information of the user terminal to the central cooperative node according to the PMI statistical channel correlation matrix in the CSI reported by the user terminal multiple times.
  • step 42 can use one of the following five ways:
  • the scheduling information received by the cooperative base station includes the identification information of the user terminal scheduled on the scheduling resource and does not include signal state information and/or interference state information of other coordinated base stations, and the user
  • the terminal is a serving user terminal of the cooperative base station, and determines, according to the recently received CSI of the user terminal, a transmission parameter used by the cooperative base station to perform single-point transmission to the user terminal on the scheduling resource, including a precoding matrix, CQI, MCS information, etc.; or,
  • the scheduling information received by the coordinated base station includes the identity information of the user terminal scheduled on the scheduling resource and the signal state information and/or interference state information of other coordinated base stations, and the user terminal is the serving user terminal of the cooperative base station, Obtaining CSI consistent with the signal state information and/or the interference state information from the recently received CSI of the user terminal, and determining, according to the obtained CSI, that the cooperative base station uses the CoMP transmission to the user terminal on the scheduling resource.
  • the transmission parameters include a precoding matrix, CQI, MCS information, etc.; when the scheduling information does not include signal state information, the cooperative base station uses the base station as a signal transmission base station of the user terminal.
  • the CSI that is consistent with the signal state information and/or the interference state information is obtained from the recently received CSI of the user terminal, and the scheduling information received by the coordinated base station is scheduled to be scheduled on the scheduling resource.
  • the identification information of the user terminal and the signal state information of the other coordinated base station indicate that the other coordinated base station is the signal transmission base station of the user terminal
  • the other coordinated base station is obtained as the user terminal from the CSI of the recently received user terminal.
  • the base station that performs interference avoidance or silence on the CoMP transmission of the user terminal obtains the CSI of the user terminal when the other coordinated base station performs interference avoidance or silence from the recently received CSI of the user terminal; and receives the CSI received by the cooperative base station.
  • the scheduling information includes an identification letter of the user terminal scheduled on the scheduling resource And the signal state information and the interference state information of the other coordinated base station, indicating that the base station corresponding to the signal state information is a signal transmission base station of the user terminal, and the base station corresponding to the interference state information is performing interference avoidance for the CoMP transmission of the user terminal.
  • the silent base station when the base station corresponding to the signal state information obtained by the recently received CSI of the user terminal is used as the signal transmission base station of the user terminal, and the base station corresponding to the interference state information performs interference avoidance or silence CSI of the user terminal.
  • the scheduling information received by the cooperative base station includes the identity information of the user terminal scheduled on the scheduling resource and the signal state information and/or interference state information of other coordinated base stations, and the user terminal is not
  • the serving user terminal of the cooperative base station obtains CSI that is consistent with the signal state information and/or the interference state information from the recently received CSI of the user terminal, and determines, according to the obtained CSI, the coordinated base station on the scheduling resource.
  • the transmission parameter used by the user terminal for CoMP transmission includes a precoding matrix, CQI, MCS information, etc.; when the scheduling information does not include signal state information, the cooperative base station uses the base station as a signal transmission base station of the user terminal. .
  • the cooperative base station does not perform data transmission on the scheduling resource.
  • the cooperative base station if the scheduling information received by the cooperative base station includes information indicating that the cooperative base station is silent on the scheduling resource, the cooperative base station does not perform data transmission on the scheduling resource.
  • the cooperative base station if the cooperative base station does not receive any scheduling information for the scheduling resource or the scheduling information received by the cooperative base station includes (or includes only) information indicating that the CoMP user terminal is not scheduled, the cooperative base station according to The recently received CSI of the user terminal, for the cooperative base terminal, schedules a single point transmission and determines transmission parameters used for single point transmission, including precoding matrix, CQL MCS information, and the like.
  • the cooperative base station determines that the data transmission on the scheduling resource uses the available precoding A precoding matrix in the set of matrices and/or a precoding matrix in the set of unavailable precoding matrices is not used.
  • the scheduling information received by the coordinated base station includes a set of available precoding matrices, determining that the data transmission on the scheduling resource uses a precoding matrix in the available precoding matrix set, if the scheduling information received by the cooperative base station includes If the precoding matrix set is not available, the cooperative base station determines that the data transmission on the scheduling resource does not use the precoding matrix in the unavailable precoding matrix set, that is, uses the precoding matrix in the unusable precoding matrix set.
  • the cooperative base station determines that the data transmission on the scheduling resource uses the available precoding matrix set The precoding matrix is not used and the precoding matrix in the set of unavailable precoding matrices is not used.
  • the cooperative base station may send the channel information to the central cooperative node through the backhaul; and receive the scheduling information sent by the central cooperative node through the backhaul.
  • the interaction process between the CCN and the cooperative base station is as follows:
  • Step 1 The cooperative base station sends the channel information of the user terminal under the cooperative base station to the central cooperative node.
  • Step 2 The central cooperative node receives the channel information of the user terminal sent by each coordinated base station; performs transmission scheduling according to the channel information of the received user terminal; and obtains scheduling information corresponding to each scheduling resource according to the transmission scheduling result; Sending the scheduling information to the corresponding cooperative base station when the space is empty, so that the cooperative base station according to the recently received channel state information CSI of the user terminal Determining data transmission parameters with the scheduling information;
  • Step 3 The cooperative base station receives scheduling information sent by the central cooperative node.
  • the cooperative base station determines the data transmission parameter according to the scheduling information sent by the central coordination node and the CSI of the recently received user terminal.
  • Embodiment 1 is a diagrammatic representation of Embodiment 1:
  • This embodiment is a CS/CB scheduling embodiment of a non-ideal backhaul central scheduling information interaction method
  • base station 1 There are three base stations in the system for cooperative transmission: base station 1, base station 2 and base station 3, three base stations each have two service user terminals, and UE1 under base station 1 (CoMP user terminal, the measurement set includes base station 1 and base station 3) And UE2; UE3 under the base station 2 (CoMP user terminal, base station 2 and base station 3 in the measurement set) and UE4; UE5 and UE6 under base station 3.
  • Non-CoMP user terminals are not indicated as CoMP user terminals.
  • the above three base stations have one scheduling resource
  • the information exchange process between the cooperative base station and the CCN is as follows:
  • Step 1 All user terminals report CSI, and each base station transmits the CSI reported by each user terminal to the CCN through backhaul.
  • Step 2 CCN schedules data transmission for three base stations, schedules CS/CB transmission of UE1 for base station 1, and performs interference avoidance for base station 3; schedules single-point transmission of UE4 for base station 2; schedules single point of UE5 for base station 3.
  • the CCN transmits the scheduling information to the base station 1, where the scheduling information includes: the user terminal identifier "001" of the UE1 in the scheduling user identification field; the interference status information is the identifier "11" indicating the base station 3;
  • the CCN does not transmit any scheduling information to the base station 2;
  • the CCN transmits scheduling information to the base station 3, the scheduling information including: a set of available precoding matrices.
  • Step 3 The three base stations respectively receive scheduling information.
  • the base station 1 determines that the UE1 is the scheduling user according to the scheduling user identifier "001" notified by the CCN. According to the base station 3 identifier "11" in the interference state information, the base station 3 is determined to be the interference avoidance base station, and the precoding matrix and the CQI used for data transmission on the scheduling resource are calculated according to the CSI recently reported by the UE1;
  • the base station 2 performs scheduling according to the CSI recently reported by the UE3 and the UE4, and specifically schedules the single-point transmission of the UE3, and uses the CSI recently reported by the UE3 to calculate a precoding matrix and CQI information used for data transmission on the scheduling resource;
  • the base station 3 performs scheduling according to the CSI recently reported by the UE5 and the UE6, and does not use a precoding matrix other than the set of available precoding matrices; schedules a single point transmission of the UE5, wherein the precoding matrix is closest to the UE5 within the set of available precoding matrices
  • the CSI reports the selection, and the CQI is calculated based on the selected precoding matrix.
  • Embodiment 2 is a diagrammatic representation of Embodiment 1:
  • This embodiment is a DPS/DPB scheduling embodiment of a non-ideal backhaul central scheduling information interaction method
  • the system 4 is the same as in the first embodiment.
  • the information exchange process between the cooperative base station and the CCN is as follows:
  • Step 1 All user terminals report CSI, and each base station transmits the CSI information reported by each user terminal to the CCN through backhaul.
  • Step 2 The CCN scheduling base station 1 is silent, scheduling the single-point transmission of UE4 for the base station 2, and scheduling the DPS/DPB transmission of the UE1 for the base station 3;
  • the CCN transmits scheduling information to the base station 1, where the scheduling information includes: "1" on the information field indicating silence;
  • the CCN transmits scheduling information to the base station 2, where the scheduling information includes: a user terminal identifier "100" of the UE4 in the scheduling user identification field;
  • the CCN transmits scheduling information to the base station 3, where the scheduling information includes: a user terminal identifier "001" for the UE1 in the scheduling user identification field, and an identifier "01" indicating the base station 1 in the interference status information field;
  • Step 3 The three base stations respectively receive scheduling information.
  • the base station 1 does not perform data transmission according to the identifier on the silent information field;
  • the base station 2 determines, according to the scheduling user identifier field, that the UE4 is the target user terminal, according to the latest information of the UE4;
  • the base station 3 determines that the UE1 is the target user terminal according to the scheduling user identification field. Since the UE1 is not the serving user terminal of the local base station, and the CCN does not notify the signal status information, the transmission point of the transmission is determined to be the base station, and the interference state information is read as the base station.
  • the identifier "01" of 1 indicates that the base station 1 is silent; the base station 3 obtains, from the CSI of the UE1 notified by the base station 1, a precoding matrix and CQI information corresponding to the base station transmission and the base station 1 being silent as the scheduling information.
  • Embodiment 3 is a diagrammatic representation of Embodiment 3
  • This embodiment is a JT scheduling embodiment of a non-ideal backhaul central scheduling information interaction method
  • the system assumes the same as in the first embodiment except that the UE1 is a CoMP user terminal, the measurement set includes the base station 1, the base station 2, the base station 3, the UE3 is a non-CoMP user terminal, and the information between the cooperative base station and the CCN.
  • the interaction process is as follows:
  • Step 1 All user terminals report CSI, and each base station transmits the CSI reported by each user terminal to the CCN through backhaul.
  • Step 2 The CCN schedules the base station 1 and the base station 2 to perform JT transmission for the UE1, and the base station 3 performs single-point transmission for the UE5;
  • the CCN transmits scheduling information for the base station 1.
  • the scheduling information includes: a user terminal identifier "001" for the UE1 in the scheduling user identification field, an identifier "01” indicating the base station 1 and an identifier "10” indicating the base station 2 in the signal status information field. " ;
  • the CCN transmits scheduling information for the base station 2, and the scheduling information includes: a user terminal identifier "001" for the UE1 in the scheduling user identification field, an identifier "01” indicating the base station 1 and an identifier "10” indicating the base station 2 in the signal status information field. " ;
  • the CCN does not transmit any scheduling information for the base station 3.
  • Step 3 The three base stations respectively receive scheduling information.
  • the base station 1 determines that the UE1 is the target user terminal according to the scheduling user identification field, according to the signal status.
  • the information field determines that the base station and the base station 2 perform JT transmission, and calculates the precoding matrix and CQI of the base station 1 as the scheduling information when the base station 1 and the base station 2 perform the JT transmission by using the CSI recently reported by the UE1;
  • the base station 2 determines that the UE1 is the target user terminal according to the scheduling user identification field. Since the UE1 is not the serving user terminal of the local base station, it is determined that the signal state information of the transmission is the base station 1 identifier "01" and the local base station identifier "10"; the base station 2 The CSI of the UE1 notified by the base station 1 obtains the precoding matrix of the CQI and the base station 2 that the base station 1 and the base station 2 perform JT transmission for the UE1 as scheduling information.
  • the base station 3 performs scheduling according to the CSI recently reported by the UE5 and the UE6, and schedules a single point transmission of the UE5, and calculates scheduling information according to the CSI recently reported by the UE5.
  • an embodiment of the present invention provides a central collaboration device, where the central collaboration device includes: a transmission scheduling unit 50, configured to receive channel information of a user terminal sent by each coordinated base station; and perform channel information according to the received user terminal.
  • Transmission scheduling configured to receive channel information of a user terminal sent by each coordinated base station; and perform channel information according to the received user terminal.
  • the information acquiring unit 51 is configured to obtain scheduling information corresponding to each scheduling resource according to the transmission scheduling result;
  • the information sending unit 52 is configured to send the scheduling information to the corresponding cooperative base station, so that the cooperative base station determines the data transmission parameter according to the channel state information CSI of the recently received user terminal and the scheduling information.
  • the information acquiring unit 51 is configured to:
  • the scheduling information corresponding to the scheduling resource is empty, or includes information indicating that the CoMP user terminal is not scheduled, or information including the user terminal scheduled for each coordinated base station on the scheduling resource.
  • the information acquiring unit 51 is configured to:
  • the scheduling information corresponding to the scheduling resource includes: for the CoMP user terminal First scheduling information of the coordinated base station performing CS/CB transmission, second scheduling information of the base station in the measurement set for the CoMP user terminal, and Third scheduling information of other base stations other than the base station in the measurement set of the CoMP user terminal, where:
  • the first scheduling information includes identifier information of the CoMP user terminal and interference state information indicating a coordinated base station that performs interference avoidance for the CS/CB transmission;
  • the second scheduling information includes an available precoding matrix set, unavailable At least one of a precoding matrix set, transmit power constraint information, or at least one of a precoding matrix, rank information, and transmit power constraint information used for transmission;
  • the third scheduling information is empty, or includes The information of the CoMP user terminal is scheduled, or the information of the user terminal scheduled for the other base station on the scheduling resource.
  • the first scheduling information obtained by the information acquiring unit 51 further includes: at least one of a precoding matrix, a rank information, a channel quality indicator CQI information, and a modulation and coding information MCS of the scheduled CoMP user terminal.
  • the information acquiring unit 51 is configured to:
  • the scheduling information corresponding to the scheduling resource includes: fourth scheduling information for a silent cooperative base station, fifth scheduling information for a coordinated base station that performs DPS/DPB transmission to the CoMP user terminal, and a coordinated base station for silence and to the CoMP
  • the sixth scheduling information of the base station other than the cooperative base station that performs the DPS/DPB transmission by the user terminal if the DPS/DPB transmission of the CoMP user terminal is scheduled for the at least one coordinated base station on the scheduling resource, and the other coordinated base station is not scheduled as the The DPS/DPB transmission is silent, and the scheduling information corresponding to the scheduling resource includes seventh scheduling information for other base stations except the cooperative base station that performs DPS/DPB transmission to the CoMP user terminal;
  • the fourth scheduling information includes information indicating that the scheduling resource is silent; the fifth scheduling information includes interference state information indicating a silent coordinated base station; the sixth scheduling information is empty, or includes indicating that no CoMP is scheduled.
  • the information of the user terminal, or the cooperative base station included in the scheduling resource which is a silent cooperative base station and DPS/DPB transmission to the CoMP user terminal.
  • the information of the user terminal scheduled by the other coordinated base station; the seventh scheduling information is empty, or includes information indicating that the CoMP user terminal is not scheduled, or is included in the scheduling resource to perform DPS/DPB to the CoMP user terminal.
  • the fifth scheduling information obtained by the information acquiring unit 51 further includes:
  • the scheduling resource obtained by the information acquiring unit 51 corresponds to the scheduling resource.
  • the scheduling information also includes:
  • the information acquiring unit 51 is configured to:
  • the scheduling information corresponding to the scheduling resource includes: a cooperative base station that performs JT transmission to the CoMP user terminal.
  • the eighth scheduling information includes: the identification information of the CoMP user terminal and the signal status information of the cooperative base station that performs JT transmission to the CoMP user terminal.
  • the seventh scheduling information obtained by the information acquiring unit 51 further includes:
  • the transmission scheduling unit 50 is configured to: receive channel information of the user terminal sent by each cooperation base station by using a backhaul link backhaul;
  • the information sending unit 52 is configured to: send scheduling information to the cooperative base station by using backhaul.
  • the cooperative base station includes: a sending unit 60, configured to send, to a central cooperative node, channel information of a user terminal under the cooperative base station;
  • the receiving unit 61 is configured to receive scheduling information sent by the central cooperative node.
  • the processing unit 62 is configured to determine a data transmission parameter according to the scheduling information sent by the central cooperative node and the channel state information CSI of the recently received user terminal.
  • the sending unit 60 is configured to:
  • processing unit 62 is configured to:
  • the serving user terminal determines, according to the recently received CSI of the user terminal, a transmission parameter used by the cooperative base station to perform single-point transmission to the user terminal on the scheduling resource; or
  • the received scheduling information includes the identity information of the user terminal scheduled on the scheduling resource and the signal state information and/or interference state information of other coordinated base stations, and the user terminal is the serving user terminal of the cooperative base station, Obtaining, in the CSI of the user terminal, the CSI that is consistent with the signal state information and/or the interference state information, and determining, according to the obtained CSI, the transmission used by the cooperative base station to perform CoMP transmission on the scheduling resource to the user terminal.
  • Parameter When the scheduling information does not include signal status information, the cooperative base station is used as a signal transmission base station of the user terminal.
  • processing unit 62 is configured to:
  • the received scheduling information includes the identification information of the user terminal scheduled on the scheduling resource and the signal state information and/or interference state information of other coordinated base stations, and the user terminal is not the service of the cooperative base station.
  • the user terminal obtains CSI consistent with the signal state information and/or the interference state information from the recently received CSI of the user terminal, according to the obtained CSI. Determining, by the cooperative base station, a transmission parameter used for CoMP transmission to the user terminal on the scheduling resource; when the scheduling information does not include signal state information, the base station is used as a signal transmission base station of the user terminal.
  • processing unit 62 is configured to:
  • the received scheduling information includes information indicating that the cooperative base station is silent on the scheduling resource, no data transmission is performed on the scheduling resource.
  • processing unit 62 is configured to:
  • the collaboration is based on the CSI of the recently received user terminal.
  • processing unit 62 is configured to:
  • the received scheduling information includes a set of available precoding matrices and/or a set of unavailable precoding matrices, then determining that the data transmissions on the scheduling resources use the available precoding matrices.
  • the sending unit 60 sends the channel information to the central cooperative node through a backhaul link backhaul;
  • FIG. 7 is a schematic structural diagram of a center collaboration device according to another embodiment of the present invention.
  • the center collaboration device is applicable to the foregoing embodiment of the present invention.
  • the central collaboration device can include: a memory 71 and a processor 72, wherein:
  • the memory 71 stores one or more executable programs, which are used to configure the processor 72;
  • the processor 72 is configured with one or more executable programs for performing the following methods:
  • the scheduling information is sent to the corresponding cooperative base station, so that the cooperative base station determines the data transmission parameter according to the channel state information CSI of the recently received user terminal and the scheduling information.
  • the processor 72 can refer to the foregoing embodiment, and is not repeated here.
  • FIG. 8 is a schematic structural diagram of a cooperative base station according to another embodiment of the present invention.
  • the cooperative base station is applicable to the foregoing embodiments of the present invention.
  • the cooperative base station can include a memory 81 and a processor 82, wherein:
  • the memory 81 stores one or more executable programs, which are used to configure the processor 82;
  • the processor 82 is configured with one or more executable programs for performing the following methods:
  • the data transmission parameter is determined according to the scheduling information sent by the central coordination node and the channel state information CSI of the recently received user terminal.
  • the processor 82 can refer to the foregoing embodiment, and is not repeated here.
  • the beneficial effects of the present invention include:
  • the central cooperative node performs transmission scheduling according to the channel information of the user terminal sent by each coordinated base station, and obtains scheduling information corresponding to each scheduling resource, and sends the scheduling information to the corresponding coordinated base station, and cooperates.
  • the base station determines the data transmission parameter according to the scheduling information sent by the central coordination node and the CSI of the recently received user terminal. It can be seen that, in this solution, the central cooperative node only needs to send partial scheduling information to the cooperative base station, and the cooperative base station according to the partial scheduling information
  • the data transmission scheduling and/or the determination of the data transmission parameters are performed in conjunction with the latest CSI directly reported by the user terminal.
  • the central coordination node needs to send all the scheduling information to the coordinated base station, and the user terminal needs to report the CSI to the central cooperative node.
  • the central cooperative node forwards the CSI to the cooperative base station.
  • the cooperative base station reduces the impact of the backhaul delay on the CoMP center scheduling, thereby improving the CoMP transmission performance.
  • embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the invention can be embodied in the form of one or more computer program products embodied on a computer-usable storage medium (including but not limited to disk storage, CD-ROM, optical storage, etc.) in which computer usable program code is embodied.
  • a computer-usable storage medium including but not limited to disk storage, CD-ROM, optical storage, etc.
  • the computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device.
  • the apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.
  • These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device.
  • the instructions provide steps for implementing the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Procédé et dispositif de programmation d'émission, se rapportant au domaine des communications sans fil, et utilisés pour améliorer les performances d'émission coordonnée multipoint (CoMP). Dans la présente invention, après la programmation d'émission, en fonction d'informations de canaux de terminaux d'utilisateurs émises par chaque station de base coopérative, le nœud coopératif central acquiert des informations de programmation correspondant à chaque ressource de programmation et utilisées par des stations de base coopératives pour programmer l'émission de données et/ou déterminer des paramètres d'émission, puis envoie les informations de programmation à une station de base coopérative correspondante. La station de base coopérative détermine des paramètres d'émission de données, en se basant sur les informations de programmation émises par le nœud coopératif central et sur les informations d'état de canal (CSI) récemment reçues des terminaux d'utilisateurs. Les performances d'émission CoMP sont améliorées à l'aide de la présente invention.
PCT/CN2014/075235 2013-04-15 2014-04-14 Procédé et dispositif de programmation d'émission Ceased WO2014169794A1 (fr)

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WO2017008285A1 (fr) * 2015-07-15 2017-01-19 华为技术有限公司 Procédé et dispositif de communication par liaison terrestre sans fil
WO2017096524A1 (fr) * 2015-12-08 2017-06-15 Telefonaktiebolaget Lm Ericsson (Publ) Transmission multipoint coordonnée (comp) depuis une grappe comp
CN107872260B (zh) 2016-09-28 2021-03-05 华为技术有限公司 通信方法及网络设备
WO2018203436A1 (fr) * 2017-05-01 2018-11-08 日本電気株式会社 Dispositif de commande, procédé, programme et support d'enregistrement
CN110247717A (zh) * 2018-03-07 2019-09-17 索尼公司 用于无线通信的电子设备、方法和计算机可读存储介质

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