[0027] In the embodiment of the present invention, the first access point in the wireless network sends the information transmitted on the data channel allocated to the user terminal to the second access point, and the first access point does not transmit on the data channel data.
[0028] The second access point uses the data channel to send data to the user terminal according to the information transmitted by the data channel allocated to the user terminal.
[0029] In practical applications, the above-mentioned wireless network may be a heterogeneous network or a homogeneous network.
[0030] In practical applications, the above-mentioned first access point may be a device such as a macro base station, a micro base station, a home base station, and a relay station, and the above-mentioned second access point may be a device such as a macro base station, a micro base station, a home base station, or a relay station.
[0031] In practical applications, the aforementioned user terminal may be an LTE user equipment or an LTE-A user equipment or a relay node or a device with receiving capability in a future wireless system.
[0032] In the following description, a network technology in a wireless network, that is, a heterogeneous network technology, is used to illustrate the embodiments of the present invention, but it is also applicable to other wireless network systems.
[0033] Hereinafter, the embodiment of the present invention is described by taking the foregoing first access point as a serving macro base station and the foregoing second access point as a serving micro base station as an example.
[0034] In order to facilitate the understanding of the embodiments of the present invention, further explanations will be made below with reference to the drawings and specific embodiments, and each embodiment does not constitute a limitation to the embodiments of the present invention.
[0035] Such as figure 1 As shown, it is a schematic diagram of the processing flow of a data transmission method in a wireless network provided by an embodiment of the present invention, including the following processing steps:
[0036] Step 102: The serving macro base station sends the information transmitted by the data channel allocated to the user terminal to the serving micro base station.
[0037] Specifically, the serving macro base station sends the information transmitted by the data channel allocated by the serving macro base station to the user terminal to the above-mentioned serving micro base station through a certain interface between the serving macro base station and the serving micro base station. The interface may include that the delay is less than the first For a threshold interface, the first threshold is not greater than 1 second.
[0038] The serving macro base station can also send the PCID (Physical Channel Identifier, physical channel identifier) of the serving macro base station and the subframe number of data transmission to the above serving micro base station through a certain interface between the serving macro base station and the serving micro base station. .
[0039] The above-mentioned interface between the serving macro base station and the serving micro base station can be an X2 interface, or a MAC layer interface used to transfer MAC (Mdium Access Control, medium access control layer) information, or an S1 interface, or Other types of interfaces whose propagation delay is less than 1 second. When the serving macro base station and the serving micro base station both access the core network in a wired manner, the interface between the above serving macro base station and the serving micro base station may be a MAC layer interface. In particular, for the LTE system, when the interface between the serving macro base station and the serving micro base station adopts a wireless interface, the serving micro base station receives the wireless interface signal from the serving macro base station, while ensuring that the serving micro base station has a good connection with the LTE users in the serving cell. For backward compatibility, it is necessary to inform the user terminal of the cell that the subframe currently used to receive the radio interface signal of the serving macro base station is an MBSFN (MBMS over a Single Frequency Network, single frequency network mode bears MBMS service) subframe.
[0040] The serving macro base station sends the information transmitted by the data channel allocated to the user terminal to the user terminal through the control channel between it and the user terminal. The control channel may be the physical layer downlink control channel PDCCH in the LTE system; The information transmitted by the allocated data channel may include: radio resources occupied by the data channel and one or a combination of the following parameters: transmission mode, modulation and coding method, power allocation information, and hybrid automatic repeat request HARQ information.
[0041] The serving macro base station may also send other common channel information used for data transmission control to the user terminal. The common channel information includes but is not limited to information such as the primary synchronization channel, the secondary synchronization channel, and the physical layer broadcast channel.
[0042] The serving macro base station does not send data such as service data and control data to the user terminal on the above-mentioned data channel allocated to the user terminal, but can send the first reference signal, which can be used for channel measurement estimation, using LTE or Taking the LTE-A system as an example, the first reference signal may be a CRS. The user terminal can detect, based on the first reference signal received from the serving macro base station, the information and usage information transmitted by the serving macro base station to the user terminal through the control channel between the user terminal and the data channel allocated to the user terminal. Other common channel information for data transmission control.
[0043] Step 103: The serving micro base station uses the data channel to send data to the user terminal according to the information transmitted by the data channel, wherein the serving macro base station does not transmit data on the data channel.
[0044] Specifically, the above-mentioned serving micro base station that forms an "access point set" with the serving macro base station can use the information transmitted from the above-mentioned data channel allocated to the user terminal received from the serving macro base station to serve the identity of the macro base station (that is, use PCID of the serving macro base station), this can ensure backward compatibility for LTE user terminals in the LTE-A system, or use the serving micro base station's own PCID to provide users with The data channel allocated by the terminal sends data such as service data and control data to the user terminal. among them
[0045] Optionally, the above-mentioned serving micro base station may also send a second reference signal to the user terminal. The second reference signal may be used for data demodulation. Taking the LTE or LTE-A system as an example, the second reference signal may be a DRS ( Dedicated Reference Signal (UE-specific Reference Signal, dedicated reference signal) and/or DMRS (De-modulation Reference Signal).
[0046] The user terminal can detect data such as service data and control data sent by the serving micro base station to itself from the data channel between the serving micro base station and the user terminal according to the second reference signal received from the serving micro base station.
[0047] When the serving macro base station allocates the wireless resources of the data channel to the user terminal, it may not consider the location of the CRS of the serving micro base station itself. Therefore, the wireless resource of the data channel allocated by the serving macro base station to the user terminal may be the same as the CRS of the serving micro base station. In order to resolve this conflict, for ordinary user terminals, such as LTE user equipment, the serving micro base station needs to be unable to send data at the CRS resource location of the serving macro base station and the CRS resource location of the serving micro base station. During resource mapping, the data on the CRS resource locations permitted by the PDSCH mapping rules should be punched, that is, the data should be shielded; for advanced user terminals, such as LTE-A users, the serving micro base station can formulate new physical resource mapping rules to avoid There is an overlap problem between the resources of the data channel allocated by the serving macro base station to the user terminal and the CRS of the serving micro base station.
[0048] After the user terminal receives the service data, control data and other data sent to it by the serving micro base station, it needs to detect whether the received data is correct. If it is correct, it needs to send an ACK (ACKnowledge) signal to the serving macro base station; otherwise , Send a NACK (Not Acknowledge) signal to the serving macro base station. When the serving macro base station receives the NACK signal, it can notify the serving micro base station to retransmit data to the user terminal.
[0049] Optionally, the user terminal may send the above ACK/NACK signal to the serving micro base station, and the serving micro base station forwards the above ACK/NACK signal to the serving macro base station. When the serving macro base station receives the NACK signal, it may notify the serving micro base station. The base station retransmits the data to the user terminal.
[0050] Optionally, before step 102, step 100 and step 101 may also be included:
[0051] Step 100: The user terminal determines the serving macro base station of the user terminal;
[0052] Specifically, the user terminal may select the macro base station with the strongest signal strength as the serving macro base station according to the received downlink signal strength of each macro base station, start the wireless access process, and communicate with the selected serving macro base station.
[0053] Step 101: The serving macro base station allocates the information transmitted by the data channel to the user terminal.
[0054] The above-mentioned information transmitted by the data channel allocated to the user terminal may be: radio resources occupied by the data channel and one or a combination of the following parameters: transmission mode, modulation and coding mode, power allocation information, and hybrid automatic repeat request HARQ information.
[0055] The radio resources occupied by the above data channel mainly include information such as frequency resources and/or time resources and/or other radio resources. In the LTE system, the data channel may be the physical layer downlink shared channel PDSCH.
[0056] Specifically, the serving macro base station may be based on the channel quality parameter between the serving macro base station and the user terminal and/or the channel quality parameter between the serving micro base station and the user terminal reported by the user terminal, To allocate the information transmitted by the data channel to the user terminal, taking the LTE or LTE-A system as an example, the allocation process can refer to the following steps:
[0057] The user terminal performs detection based on the first reference signal sent to the serving macro base station, for example, CRS (Cell-specific Reference Signal, cell common reference signal), and reports to the serving macro base station the relationship between the serving macro base station and the user terminal. Channel quality parameters. The channel quality parameters can be: CQI (Channel Quality Indicator), RI (Rank Indicator), PMI (Pre-coding Matrix Indicator, pre-coding matrix indicator) and RSRP (Reference Signal Received Power) , Reference signal received power) or a combination of other parameters. The user terminal can also report to the serving macro base station the channel quality parameters between the user terminal and the serving micro base station, such as RSRP; for some user terminals with CRS detection capabilities in neighboring cells, such as LTE-A user equipment, It is also possible to detect based on the CRS of the serving micro base station, and report other channel quality parameters other than RSRP, such as CQI, RI, PMI, etc., and feed back one or a combination of the above channel quality parameters to the serving macro base station.
[0058] Taking the information transmitted on the data channel allocated to the user terminal as the transmission mode as an example, the serving macro base station can use the information fed back by the user terminal, that is, the channel quality parameters between the user terminal and the serving macro base station, and/or the user terminal and the serving micro base station. The channel quality parameter between the base stations sets the transmission mode to be used for data transmission for the user terminal. The transmission mode includes but is not limited to the data transmission mode supported by the user terminal.
[0059] Taking the information transmitted on the data channel allocated to the user terminal as the modulation and coding method as an example, for a user terminal that does not have the CRS detection function of neighboring cells, such as LTE user equipment, the serving macro base station can be based on the RSRP of the serving micro base station fed back by the user terminal, Set the modulation and coding method for the user terminal. For user terminals with CRS detection function in neighboring cells, such as LTE-A user equipment, since the channel state information between the user terminal and the serving micro base station can be fed back, such as CQI, RI, PMI, etc., the serving macro base station can be based on the user terminal The feedback of the above-mentioned channel state information between the serving micro base station and the user terminal sets the modulation and coding mode for the user terminal.
[0060] Since in the above steps, the user terminal can obtain the information transmitted by the data channel allocated to the user terminal from the serving macro base station, after the serving micro base station receives the information transmitted by the serving macro base station on the data channel allocated to the user terminal, it may not The information is sent to the user terminal to avoid mutual interference between the control channels of the serving macro base station and the serving micro base station, and to ensure that the user terminal can reliably receive the information transmitted by the data channel allocated to the user terminal.
[0061] Optionally, before step 102 and after step 100, the serving macro base station may also select a serving micro base station for the user terminal;
[0062] After receiving the downlink signal of the micro base station, the user terminal reports the RSRP of the micro base station to the serving macro base station. In practical applications, the user terminal may receive downlink signals from multiple micro base stations and report the RSRP of multiple micro base stations to the serving macro base station.
[0063] The serving macro base station selects a serving micro base station for the user according to the RSRPs of multiple micro base stations reported by the user terminal. The criteria for selecting the serving micro base station may be based on criteria such as received power intensity.
[0064] The above-mentioned serving macro base station of the user terminal and the serving micro base station selected by the serving macro base station for the user terminal constitute a set of access points served by the user terminal.
[0065] In this embodiment, the serving macro base station sends control channel information to the user terminal without sending data, and the serving micro base station sends data to the user terminal without sending control channel information, which can effectively avoid serving macro base stations and serving micro base stations in heterogeneous network scenarios. Interference between channels improves data transmission performance.
[0066] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing relevant hardware through a computer program. The program can be stored in a computer readable storage medium. During execution, it may include the procedures of the above-mentioned method embodiments. Wherein, the storage medium may be a magnetic disk, an optical disc, a read-only memory (Read-Only Memory, ROM), or a random access memory (Random Access Memory, RAM), etc.
[0067] Corresponding to the foregoing method embodiment, an embodiment of the present invention also provides a first access point in a wireless network. The schematic structural diagram is as figure 2 As shown, it includes the following modules:
[0068] The resource allocation module 21 is used to allocate information transmitted by the data channel to the user terminal;
[0069] The above-mentioned information transmitted by the data channel allocated to the user terminal may be: radio resources occupied by the data channel and one or a combination of the following parameters: transmission mode, modulation and coding mode, power allocation information, and hybrid automatic repeat request HARQ information.
[0070] The radio resources occupied by the above data channel mainly include information such as frequency resources and/or time resources and/or other radio resources. In the LTE system, the data channel may be the physical layer downlink shared channel PDSCH.
[0071] Specifically, the resource allocation module 21 may be based on the channel quality parameters between the first access point and the user terminal reported by the user terminal and/or the second access point and the user terminal Between the channel quality parameters, the information transmitted by the data channel is allocated to the user terminal.
[0072] The channel quality parameters can be: CQI (Channel Quality Indicator, channel quality indicator), RI (Rank Indicator, rank indicator), PMI (Pre-coding Matrix Indicator, pre-coding matrix indicator) and RSRP (Reference Signal Received Power, reference signal) Received power) and other parameters or a combination.
[0073] The resource information sending module 22 is configured to send the information transmitted by the data channel allocated to the user terminal to the second access point;
[0074] Specifically, the resource information sending module 22 sends the information transmitted by the data channel allocated to the user terminal to the second access point through the interface between the first access point and the second access point. Access point; the interface between the first access point and the second access point includes: an interface with a delay less than a first threshold, and the first threshold is not greater than 1 second.
[0075] Wherein, the first access point does not transmit data on the data channel.
[0076] The first access point may further include:
[0077] The second access point selection module is configured to select the second access point for the user terminal.
[0078] A reference information sending module, configured to send a first reference signal to a user terminal by using the data channel;
[0079] The information sending module for data channel transmission is further configured to send the information transmitted by the data channel allocated to the user terminal to the user terminal through the control channel between the first access point and the user terminal, so that the user According to the information transmitted by the data channel, the terminal receives the data sent by the second access point to the user terminal by using the data channel.
[0080] The foregoing first access point may be a serving macro base station of the user terminal.
[0081] In the embodiment of the present invention, the second access point sends data to the user terminal according to the information transmitted by the first access point on the data channel allocated to the user terminal, and the first access point does not use the allocated data channel. Sending data to the user terminal can effectively avoid interference between the second access point and the first access point in a heterogeneous network scenario, and improve transmission performance.
[0082] Corresponding to the foregoing method embodiment, an embodiment of the present invention also provides a second access point in a wireless network. The schematic structural diagram is as follows: image 3 As shown, it includes the following modules:
[0083] The resource information receiving module 31 is configured to receive information transmitted by the data channel allocated to the user terminal by the first access point;
[0084] The data sending module 32 is configured to use the data channel to send data to the user terminal according to the information transmitted by the data channel;
[0085] Wherein, the first access point does not transmit data on the data channel.
[0086] The data sending module 32 is specifically configured to use the information transmitted by the data channel allocated to the user terminal received from the first access point to the first access point or the second access point Using the data channel to send data to the user terminal.
[0087] The aforementioned second access point may be a serving micro base station of the user terminal.
[0088] In summary, the embodiment of the present invention proposes a new wireless network data transmission scheme. The serving macro base station sends the information transmitted by the allocated data channel to the user terminal while not sending data on the corresponding data channel. The micro base station sends data to the user terminal on the data channel corresponding to the information transmitted by the data channel allocated to the user terminal by the serving macro base station; this solution can effectively avoid the interference between the control channels of different access points in the wireless network system, thereby ensuring The user terminal can reliably receive the control channel of the serving node, thereby ensuring effective data communication between the user terminal and the serving node.
[0089] In the embodiment of the present invention, the user terminal can make full use of the control signal quality of the macro base station, improve the reliability of control channel reception, and can make full use of the resources of the micro cell for data transmission.
[0090] For LTE and LTE-A systems, the data transmission mode provided in the embodiments of the present invention is also transparent to user terminals that do not have cooperative reception capabilities (ie, LTE terminal users), that is, it can ensure backward compatibility with LTE user equipment.
[0091] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Any person skilled in the art can easily think of changes or changes within the technical scope disclosed by the present invention. All replacements shall be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
