WO2013071660A1

WO2013071660A1 - Method and apparatus for macro diversity reception

Info

Publication number: WO2013071660A1
Application number: PCT/CN2011/083395
Authority: WO
Inventors: 丁杰伟; 沈伟; 蒲迎春; 翟毅斌
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-11-16
Filing date: 2011-12-02
Publication date: 2013-05-23
Also published as: CN103117789A

Abstract

Disclosed are a method and apparatus for macro diversity reception. The method comprises: a base station searches signals of the same mobile terminal in multi co-frequency cells; the base station demodulates the signals, of the mobile terminal, searched in the multi co-frequency cells and combines the demodulation results. In the present invention, the base station searches independently signals from co-frequency and adjacent cells and performs macro diversity combination, so that the base station can obtain macro diversity gain even in the circumstance that the terminal is not handed off, and furthermore, the system performance can be upgraded and the user experience can be improved.

Description

TECHNICAL FIELD The present invention relates to the field of communications, and in particular to a macro diversity receiving method and apparatus. Background Art Currently, widely used wireless communication systems include: Global System for Mobile (Global System for Mobile)

Communication, abbreviated as GSM), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), Time Division Synchronous Code Division Multiple Access (CDMA) Time Division-Synchronous Code Division Multiple Access (TD-SCDMA), Worldwide Interoperability for Microwave Access (Wimax), Long-Term Evolution (LTE), etc. . In the architecture of the above wireless communication system, the network coverage is composed of many cells covering different areas. When the mobile terminal moves between cells, it needs to perform cell handover. According to the protocol, whether the handover needs to be measured by the mobile terminal to measure the downlink signal quality of each cell is determined. If handover is required, the radio network controller initiates handover signaling. In the soft handover and softer handover procedures, the mobile terminal can maintain communication with multiple cells at the same time, and the radio network controller initiates signaling to establish a radio link in each cell. The mobile terminal is in a process of multiple cell soft handover or softer handover, and the uplink signal may be jointly received and combined by multiple cells to obtain macro diversity gain of multiple cells, but the premise is that the radio network controller notifies the base station to establish multiple radios. Link, the signaling process of this handover also needs a certain time process. The macro diversity gain is not available during the handover but the handover signaling has not yet been completed. In the case where the handover threshold has not been reached but the handover threshold has been approached, the originally available macro diversity gain is also not obtained, and the mobile terminal may also cause undesirable interference to other cells. As the demand for better and faster wireless communication systems becomes stronger and stronger, the wireless communication system has a faster pace of scheduling and scheduling of wireless resources, and the relatively slow and complex handover signaling process has been difficult to keep up with the fast-paced communication process. For example, in WCDMA, the 3GPP protocol defines an uplink Cell Fach enhancement function, which uses a shared enhanced dedicated channel (Common E-Dch). The channel is time-sharing shared to each mobile terminal that needs to communicate. Usually, the short-term burst data transmission can use the channel, and the transmission process terminal has a large transmission power and a short duration. Due to the short duration, it is difficult to design a handover process for such a shared channel, and the macro diversity gain cannot be switched. In addition, the burst power itself requires a large transmission power, which also causes a large interference to other neighboring cells. . When the macro diversity gain is obtained in the related art, the switching time is too long and the switching process is strict, which results in the inability to receive the macro diversity gain. Currently, no effective solution has been proposed. SUMMARY OF THE INVENTION The present invention provides a macro diversity receiving method and apparatus, to at least solve the problem that when the macro diversity gain is acquired in the related art, the switching time is too long and the switching process is strict, resulting in failure to receive the macro diversity gain. According to an aspect of the present invention, a macro diversity receiving method is provided, including: a base station searching for signals of the same mobile terminal in a plurality of intra-frequency cells; and deactivating, by the base station, the mobile terminal searched in the plurality of intra-frequency cells The signals are combined and the above demodulation results are combined. Preferably, the multiple intra-frequency cells include: a primary cell where the mobile terminal is located and an intra-frequency cell adjacent to the primary cell. Preferably, the base station combines the demodulation results using a maximum ratio combining method. Preferably, after the base station demodulates the signals of the mobile terminal searched in the plurality of intra-frequency cells and combines the demodulation results, the method further includes: performing channel decoding on the combined demodulation result. Preferably, the searching, by the base station, the signals of the same mobile terminal in the multiple intra-frequency cells comprises: the base station periodically searching for signals of the same mobile terminal in the multiple intra-frequency cells. Preferably, the above macro diversity receiving method is applied to a cellular mobile communication system. According to another aspect of the present invention, a macro diversity receiving apparatus is provided, including: a search module configured to search for signals of the same mobile terminal in a plurality of co-frequency cells; a demodulation combining module, configured to demodulate in multiple The signals of the mobile terminals searched in the same frequency cell and combine the demodulation results. Preferably, the search module further includes: a first search submodule configured to search for a signal of the mobile terminal in a primary cell where the mobile terminal is located; and a second search submodule configured to search for the mobile terminal in an intra-frequency cell adjacent to the primary cell signal of. Preferably, the demodulation combining module combines the demodulation results by a maximum ratio combining method. Preferably, the above macro diversity receiving apparatus further includes: a channel decoding module, configured to perform channel decoding on the combined demodulation result. According to the present invention, a method of searching for signals of the same mobile terminal in a plurality of intra-frequency cells and demodulating and merging the searched signals is adopted, and when the macro diversity gain is acquired in the related art, the switching time is too long and the handover is performed. The requirements are stricter in the process, which makes it impossible to receive the macro diversity gain. In the case of no switching, the macro diversity gain can be easily received, which improves the system performance and improves the user experience. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a flowchart of a macro diversity receiving method according to an embodiment of the present invention; FIG. 2 is a flowchart of a macro diversity receiving method according to a preferred embodiment of the present invention; FIG. 3 is a preferred embodiment according to the present invention. 2 is a schematic diagram of a macro diversity receiving scenario; FIG. 4 is a block diagram showing a structure of a macro diversity receiving apparatus according to an embodiment of the present invention; FIG. 5 is a block diagram 2 of a macro diversity receiving apparatus according to an embodiment of the present invention; A schematic diagram of a macro diversity receiving apparatus of a preferred embodiment 3 of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. When the macro diversity gain is obtained in the related art, the switching time is too long and the switching process is strict, which may result in the inability to receive the macro diversity gain. The embodiment of the present invention provides a macro diversity receiving method. 1 is a flow chart of a macro diversity receiving method according to an embodiment of the present invention. As shown in FIG. 1, the macro diversity receiving method includes: Step S102: A base station searches for signals of the same mobile terminal in multiple intra-frequency cells; Step S104: The base station demodulates mobile terminals that are searched in multiple intra-frequency cells The signals are combined and the above demodulation results are combined. According to the foregoing embodiment, the method for searching for signals of the same mobile terminal in multiple intra-frequency cells and demodulating and merging the searched signals solves the problem that the switching time is too long when the macro diversity gain is obtained in the related art. Moreover, the requirements of the handover process are strict, which makes it impossible to receive the macro diversity gain. In the case of no handover, the macro diversity gain can be easily received, the system performance is improved, and the user experience is improved. The multiple intra-frequency cells include: a primary cell where the mobile terminal is located and an intra-frequency cell adjacent to the primary cell. In the implementation process, for any mobile terminal in the communication state in the base station, the base station may actively search for the signal of the terminal UE on the antenna of the primary cell where the mobile terminal is located and the same frequency cell adjacent to the primary cell. Even in the absence of a handover, the base station can actively perform a signal search and acquire the macro diversity gain using the searched signals. Improve the performance of the system. In step S104, the base station may combine the demodulation results by a maximum ratio combining method. The maximum ratio combining method is a method that can obtain better macro gain in the implementation process. By combining the maximum ratios, a better combining gain can be obtained. After step S104, the following processing may also be included: channel decoding is performed on the combined demodulation result. By combining the channels before channel decoding, the macro diversity gain can be better obtained. Preferably, the step S102 is further processed as follows: the base station periodically searches for signals of the same mobile terminal in multiple intra-frequency cells. During the implementation process, the base station may search for signals in multiple intra-frequency cells, and may not search for the signal during the first search. During the periodic search, the base station may make up for the first time that the signal is not searched. Defects, you can use the previously unsearched signal again, through the periodic search, you can get the good macro diversity gain. Preferably, the above macro diversity receiving method is applied to a cellular mobile communication system. The preferred embodiment is directed to the problem that the cell edge performance is poor and the mobile terminal interferes with other neighboring cells in the wireless communication system. The embodiment of the present invention provides an uplink autonomous macro diversity receiving method, as shown in FIG. 2 . 2 is a flow chart of a macro diversity receiving method in accordance with a preferred embodiment of the present invention. The following processing is included: Step S202: The base station actively performs signal search of all intra-frequency neighboring cells on the terminal UE in communication. For any terminal that is in communication state (for example, terminal UE1) in any of the cells in the base station A (for example, the cell C1), the base station actively searches for the same-frequency cells in the base station A and adjacent to the cell C1 (for example: The signal of the terminal UE1 on the antenna of C2, C3, ..., Cn). Step S204: The base station demodulates and combines all the cells that search for the signal of each terminal UE to obtain a macro diversity gain. If the signal of the terminal UE1 is found on a neighboring intra-frequency cell (eg, Ci, i=2, 3, . . . , n) of the cell (C1), the signal of the terminal UE1 on the cell Ci is performed. Demodulation, and the solution in cell C1 The modulated signals are combined to obtain a macro diversity gain. If the signal of the terminal UE1 is not found on a neighboring co-frequency cell Ci, the cell Ci is not demodulated for the terminal UE1. In this implementation, the base station controller does not use the slow and complex handover signaling procedure of the base station controller, and the base station autonomously searches for the uplink signals of the mobile terminals in the communication state of multiple neighboring cells. If signals are found in multiple cells at the same time, the signals of the cells are demodulated. Combining, the diversity gain is obtained, thereby reducing the transmission power of the mobile terminal and reducing the interference between cells. Preferred Embodiment 2 FIG. 3 is a schematic diagram of a macro diversity reception scenario according to a preferred embodiment 2 of the present invention. In the same base station, there are usually multiple co-frequency cells in the neighboring cell. As shown in FIG. 3, the base station A has three co-frequency cells Cl, C2, and C3. If the user terminal switches softer in these neighboring intervals, the macro diversity gain of the cell in which the handover is performed can be obtained. However, in the actual implementation process, although the signals of many terminals can reach multiple cell antennas at the same time, not all of these terminals can obtain the macro diversity gain of all the above cells. The thick line between FIG. 3 indicates that the signal between the UE and the cell antenna is strong, and the base station controller has notified the base station that the radio link between the UE is established, and the thin line indicates that the UE has a signal to reach the cell. , but no wireless link is established. As shown in Figure 3, base station A has three co-frequency cells Cl, C2, and C3. UE1 is in a softer handover state of CI and C2, and its signal can also be received by the antenna of cell C3, but according to the conventional technology, C3 Without the radio link of UE1, the signal on C3 will not be used for diversity reception. UE2 is in the C2 cell, and no softer handover is performed, but the signal of UE2 can reach the cell C3, and the macro diversity gain of C3 is not obtained according to the conventional technique. The signal of UE3 in the figure is only detected on cell C3. Therefore, the macro diversity gain cannot be obtained. In the process of implementing this embodiment, in the first step, the base station actively performs signal search of all intra-frequency neighboring cells for the terminal UE in communication. For example, in FIG. 3, for UE1, UE2, and UE3, signal search is performed on Cl, C2, and C3 at the same time, wherein the search may be performed periodically. In the second step, all the cells that search for signals of each terminal UE are demodulated and combined to obtain a macro diversity gain. For example, in FIG. 3, for UE1, signals are searched on all cells, and signals of all cells are demodulated and combined. For UE2, signals are received on cell C2 and cell C3, and are received on cell C1. To the signal, only the C2 and C3 cell signals are demodulated and combined to obtain macro diversity gain. For UE3, only the signal is received at cell C3, and only the signal on C3 is demodulated. Then, if the method of the present embodiment is employed, all UEs, whether or not they are in a softer handover state, can search for signals on all cell antennas to obtain diversity gain. This improves system performance. 4 is a block diagram showing the structure of a macro diversity receiving apparatus according to an embodiment of the present invention. As shown in FIG. 4, the macro diversity receiving apparatus includes: a search module 10 configured to search for signals of the same mobile terminal in a plurality of intra-frequency cells; The demodulation combining module 20 is configured to demodulate signals of the mobile terminals searched in the plurality of intra-frequency cells and combine the demodulation results. The search module 10 and the demodulation combining module 20 are connected. Preferably, the macro diversity receiving apparatus further includes: a channel decoding module 30 connected to the demodulation and combining module 20, configured to perform channel decoding on the combined demodulation result. As shown in FIG. 5, the search module 10 further includes: a first search sub-module 102, configured to search for a signal of the mobile terminal in a primary cell where the mobile terminal is located; a second search sub-module 104, and a first search sub-module 102. Connect, set to search for signals of the mobile terminal in the same frequency cell adjacent to the primary cell. Preferably, the demodulation combining module may combine the demodulation results by a maximum ratio combining method. Preferred Embodiment 3 is a schematic diagram of a macro diversity receiving apparatus according to a preferred embodiment 3 of the present invention, as shown in FIG. As shown in FIG. 6, the apparatus includes: a primary cell signal search module 40, a neighbor cell signal search module 50, and a demodulation merge module 60. The device has a primary cell signal search module 40 and a plurality of adjacent cell signal search modules 50. For example, if the terminal UE can search for 4 adjacent co-frequency cells to have their signals, then four adjacent cell signal search modules are allocated. The demodulation combining module 60 is arranged to demodulate the searched signals and combine the demodulated signals. The signal output to the demodulation combining module 60 is channel decoded to obtain a stronger macro diversity gain. In the implementation process, for the UE in communication, whether the UE is in a softer handover state, the primary cell signal search module 40 performs signal search in the primary cell, and the neighbor cell signal search module 50 performs active on all other neighboring cells in the base station. Periodic signal search. For the cell that searches for the signal, the demodulation and combining module 60 performs signal demodulation on the cell, and combines with other cell demodulation results, and sends the combined result to the subsequent module for channel decoding. This method can be combined before channel decoding to obtain better macro diversity gain. The preferred embodiment uses WCDMA as a preferred implementation. The flow of the above-described embodiment applied to the macro diversity receiving apparatus will be described with reference to Figs. 2, 3, and 6. In a WCDMA base station, multiple co-frequency cells are usually configured, and different regions and antennas are used to cover different regions, and these cells are also usually adjacent. When the user establishes communication, generally only a radio link is established in a cell with better signal quality. According to the existing technology, the baseband processing subsystem in the base station only performs signal detection on the antenna allocation signal search module resources of the one cell. search for. The signal detection search in the WCDMA system searches for the frame header position of the user multipath signal on the antenna data, or simply multipath search, and frame synchronization is the basis of signal reception. In the actual implementation process, other users in the same frequency neighboring area are also likely to have the signal of the user. For example, UE2 in FIG. 1 only establishes a radio link on cell C2, and the existing method performs multipath search only on the antenna of cell C2. In this embodiment, although the base station controller establishes only one radio link of the cell to the UE2, that is, the radio link established with the cell C2, the base cell signal search module 40 and the neighbor cell signal search module 50 may perform the radio link. In the search, a total of three search modules, that is, one primary cell signal search module 40 and two adjacent cell signal search modules 50 are allocated, and multi-path search is simultaneously performed on the cells C1, C2, and C3. Both the cell C1 and the cell C3 can receive the multipath signal acquisition frame synchronization of the UE2, and the UE2 signal is not received on the cell C1. The demodulation combining module 60 demodulates and combines the signals of UE2 on the cells C2 and C3 according to the search result. Here, the signal combining can adopt the maximum ratio combining method, and a better combining gain can be obtained by this method. The combined signal can be subsequently subjected to channel decoding processing. For example, UE1, even if it is already in two cell handover states, using the apparatus and method provided in this embodiment, the signals on the cell C3 can be additionally searched for demodulation and combining to obtain additional gain. From the above description, it can be seen that the present invention achieves the following technical effects: the base station can independently search for signals of the user channels in adjacent cells regardless of whether it is in the handover scenario, and use these signals if the signals can be searched. Performing macro-diversity aggregation solves the problem that when the macro-diversity gain is obtained in the related art, the switching time is too long and the switching process is strict, resulting in the inability to receive the macro diversity gain, improving the receiving performance of these user channels, thereby reducing the mobile terminal The required transmit power reduces interference between cells. In addition, without switching, the macro diversity gain can be easily received, which improves system performance and improves user experience. Industrial Applicability The present invention can be used for macro diversity reception in a wireless communication system by searching signals of the same mobile terminal in a plurality of co-frequency cells, and demodulating and merging the searched signals so that there is no handover It can also easily receive macro diversity gain, improve system performance and improve user experience. Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A macro diversity receiving method, comprising:

The base station searches for signals of the same mobile terminal in multiple intra-frequency cells;

The base station demodulates signals of the mobile terminal searched in the plurality of intra-frequency cells and combines the demodulation results.

The method according to claim 1, wherein the multiple intra-frequency cells comprise: a primary cell in which the mobile terminal is located and an intra-frequency cell adjacent to the primary cell.

The method according to claim 1 or 2, wherein the base station combines the demodulation results by a maximum ratio combining method.

The method according to claim 3, wherein, after the base station demodulates the signal of the mobile terminal searched in the multiple co-frequency cells and combines the demodulation results, the method further includes: combining The subsequent demodulation result is subjected to channel decoding.

The method according to claim 4, wherein the searching, by the base station, the signals of the same mobile terminal in the multiple intra-frequency cells comprises:

The base station periodically searches for signals of the same mobile terminal in the plurality of intra-frequency cells.

The method according to claim 1, wherein the macro diversity receiving method is applied to a cellular mobile communication system.

7. A macro diversity receiving device, comprising:

a search module, configured to search for signals of the same mobile terminal in a plurality of co-frequency cells; a demodulation combining module configured to demodulate signals of the mobile terminal searched in the plurality of co-frequency cells and merge the signals Demodulation results.

The device according to claim 7, wherein the search module further comprises: a first search submodule, configured to search for a signal of the mobile terminal in a primary cell where the mobile terminal is located;

And a second search submodule, configured to search for a signal of the mobile terminal in a same frequency cell adjacent to the primary cell.

9. The apparatus according to claim 7 or 8, wherein the demodulation combining module combines the demodulation results by a maximum ratio combining method.

The device according to claim 9, wherein the macro diversity receiving device further comprises:

The channel decoding module is configured to perform channel decoding on the combined demodulation result.