CN1787402A - Synchronous channel configuration method of six cell base station and system of six cell base station - Google Patents

Abstract

The invention relates to a method for configuring synchronous channels of base stations of six cells. The method specifically includes: establishing a corresponding relationship between each cell of the base station and a time offset parameter; in the corresponding relationship, the time offset parameters of adjacent cells are not adjacent; and determining the synchronization code of the synchronous channel of the cell according to the corresponding relationship. The invention also provides a six-cell base station system. The system is a six-cell base station system in which six sectors constitute a single-carrier configuration structure, and the time offset parameters of adjacent cells in the system are not adjacent. The method of the present invention can avoid the collision of primary synchronization codes between cells in a multipath environment, thereby reducing the impact of multipath interference on the user terminal synchronization process; The advantages of neighbors, thereby reducing the impact of multipath interference on the synchronization process when the user terminal performs cell search.

Description

Six-cell base station synchronization channel configuration method and six-cell base station system

technical field

The invention relates to a base station synchronization channel configuration method in a mobile communication system and a base station wireless system, in particular to a method for configuring synchronization channels of each cell in a base station with a six-sector single-carrier structure in a broadband code division multiple access system and a broadband A six-cell base station wireless system obtained by the method of the invention in a code division multiple access system.

Background technique

The Wideband Code Division Multiple Access (WCDMA, Wideband Code Division Multiple Access) communication system adopts an asynchronous method, and there is no need for strict synchronization between base stations. After the mobile terminal is turned on, it needs to search for a cell to realize the connection between the mobile terminal and the network equipment including the frequency domain. , Time domain, and code domain synchronization. Synchronization in the time domain is achieved through a synchronization channel.

Synchronization Channel (SCH, Synchronization Channel) is a downlink used for cell search. The SCH includes two sub-channels, a master sync channel and a slave sync channel. The radio frame lengths of the master synchronization channel and the slave synchronization channel are both 10ms, which are divided into 15 time slots, and the length of each time slot is 2560 chips. Figure 1 describes the structure of a sync channel radio frame.

The primary synchronization channel includes a modulation code with a length of 256 chips, called the primary synchronization code (PSC, Primary Synchronization Code), represented by Cp in Figure 1, the primary synchronization code is transmitted once per time slot, and the PSCs of all cells in the system Are the same.

A modulation code with 15 sequences is repeatedly transmitted from the synchronization channel, that is, Second Synchronization Code (SSC, Second Synchronization Code). Each slave synchronization code is 256 chips long, and is transmitted in parallel with the primary synchronization code in the primary synchronization channel. In Figure 1, SSC uses Csi, k to represent the slave synchronization code, where i=0, 1,..., 63 is the serial number of the scrambling code group, and k=0, 1, 2,..., 14 is the time slot Number.

In the WCDMA system, radio resources have three fields of frequency, time, and code to describe cells and channels, and in this system, a carrier frequency in a sector is a cell. In the frequency domain, the cells of all base stations work on the same carrier frequency; in the code domain, different cells represent different cells by configuring different scrambling codes. In the time domain, it can be seen from the structure of the above-mentioned synchronization channel that the WCDMA system specifies a primary synchronization code (PSC) of the synchronization channel of all cells. Code scrambling processing, if all cells transmit at the same time with a unique synchronization code, the terminal cannot distinguish the cells, so in the time domain, the primary synchronization code (PSC) is specified so that there is a certain time offset between different cells . In the system, the parameter representing the time offset is T cell. In the wireless frame structure of the WCDMA system, the length of a time slot is 2560 chips, and the length of the synchronization channel code in a time slot is 256 chips, so the value of the parameter T cell can be 0, 1, ..., 9, representing 10 different sync codes.

In the mobile communication system, due to the complexity of the wireless propagation environment, there are multipath phenomena. In order to avoid multipath interference on the synchronization channels of different cells, the synchronization channel offset parameter T cell must be configured reasonably. If the time offset configurations of the synchronization channels of two cells are adjacent, then after multiple wireless propagations, the primary synchronization code of the latter offset cell overlaps with the primary synchronization code of the previous offset cell. Therefore, the configuration of the synchronization channel offset parameter T cell should ensure that the synchronization codes of the synchronization channels between different cells in the same base station (NodeB) cannot overlap, otherwise it will affect the cell synchronization when the terminal is turned on. Since the distribution range of a general multipath environment is less than 128 chips, and the synchronization code length is 256 chips, when configuring the time offset of the primary synchronization channel between different cells of the same site, as long as the primary synchronization between cells is satisfied If the codes are not adjacent, the normal operation of the system can be guaranteed.

In the synchronization channel configuration of the prior art, if a base station supports 3×1 configuration, then PSC collisions can be avoided as long as continuous T cell parameters are not configured when configuring the offset parameters of the three cells. Referring to FIG. 2 , which is a schematic diagram of three-cell base station synchronization channel configuration, as shown in the figure, it is only necessary to select non-adjacent time offset parameters for the three cells.

As mentioned above, the time offset parameter T cell can only be selected from 10 values of 0 to 9, and is used for the configuration of the synchronization channel. At the same time, the configuration of the main synchronization channel of the cell should meet the general principle of discontinuous time offset parameters. Therefore, when configuring 6×1 base stations, referring to the configuration method in the prior art, only five cell synchronization channels can be configured at most. If the 6×1 configuration is to be completed, the PSCs of the three cells will be continuous to each other anyway. Due to the existence of the multipath environment of wireless propagation, the collision of the PSCs between the cells cannot be avoided. When the user terminal performs cell search, due to the multi-path interference among the primary synchronization codes of three consecutive cells, the time slot synchronization is affected, thereby affecting the normal operation of the WCDMA system.

Contents of the invention

The technical problem to be solved by the present invention is to provide a six-cell base station synchronization channel configuration method, the base station system obtained by this method can reduce the influence of multipath interference on the time synchronization process when the user terminal performs cell search; at the same time, the present invention provides a method using The six-cell base station system configured by the method can enable the user terminal to reduce the impact of multipath interference on the time synchronization process when performing cell search.

In order to solve the above problems, the present invention provides a method for configuring synchronous channels of base stations of six cells. The method specifically includes: establishing a corresponding relationship between each cell of the base station and a time offset parameter; in the corresponding relationship, the time offset parameters of adjacent cells are not adjacent; and determining the synchronization code of the synchronous channel of the cell according to the corresponding relationship.

The process of establishing the corresponding relationship described in the above method is specifically: selecting three consecutive parameters in the time offset parameter field corresponding to three non-adjacent cells in the base station; The non-adjacent parameters of the above three consecutive parameters correspond to the remaining three cells in the base station. The corresponding relationship between cells and time offset parameters established by this method is as follows: the time offset parameters of the three non-adjacent cells in the base station are continuous, the time offset parameters of the other three cells are spaced from each other, and do not match the three consecutive time offset parameters are adjacent. The corresponding relationship between the cell and the time offset parameter specifically includes:

The time parameters corresponding to the three non-adjacent cells are 0, 1, and 2, and the time offset parameters of the other three cells are 4, 6, and 8;

The time parameters corresponding to the three non-adjacent cells are 1, 2, and 3, and the time offset parameters of the other three cells are 5, 7, and 9;

The time parameters corresponding to the three non-adjacent cells are 2, 3, and 4, and the time offset parameters of the other three cells are 6, 8, and 0;

The time parameters corresponding to the three non-adjacent cells are 3, 4, and 5, and the time offset parameters of the other three cells are 7, 9, and 1;

The time parameters corresponding to the three non-adjacent cells are 4, 5, and 6, and the time offset parameters of the other three cells are 8, 0, and 2;

The time parameters corresponding to the three non-adjacent cells are 5, 6, and 7, and the time offset parameters of the other three cells are 9, 1, and 3;

The time parameters corresponding to the three non-adjacent cells are 6, 7, and 8, and the time offset parameters of the other three cells are 0, 2, and 4;

The time parameters corresponding to the three non-adjacent cells are 7, 8, and 9, and the time offset parameters of the other three cells are 1, 3, and 5.

The invention also provides a base station system with six cells. The system is a six-cell base station system in which six sectors constitute a single-carrier configuration structure, and the time offset parameters of adjacent cells in the system are not adjacent.

One of the ways in which the time offset parameters of adjacent cells in the system described in the above method are not adjacent is: the time offset parameters of the three non-adjacent cells in the system are continuous, and the time offset parameters of the other three cells are spaced apart from each other , and not adjacent to the three consecutive time offset parameters.

In the method and base station system of the present invention, the time offset parameter corresponds to a synchronization code with a length of 256 chips.

Compared with the prior art, the beneficial effects brought by the present invention are: compared with the original configuration method, the method for configuring the synchronous channel of the six-cell base station provided by the present invention can make the time offset parameters between adjacent cells of the base station different from each other. Neighboring, and in the multipath environment, the collision of primary synchronization codes between cells is avoided, and the impact of multipath interference on the time synchronization process of user terminals is reduced. The present invention also provides a six-cell base station wireless system configured according to the method, so that the system has the advantage that the PSCs of adjacent cells of the base station are not adjacent, thereby reducing the impact of multipath interference on user terminals when performing cell search. The impact of the time synchronization process.

Description of drawings

Fig. 1 is a synchronous channel wireless frame structure diagram;

Fig. 2 is a schematic diagram of synchronous channel configuration of three cell base stations;

FIG. 3 is a schematic diagram of coverage of 6 cells in a base station configured with 6×1;

FIG. 4 is a schematic diagram of a synchronization channel configuration method according to the present invention;

FIG. 5 is a schematic configuration diagram of an embodiment of the synchronization channel configuration method according to the present invention.

Detailed ways

The invention provides a six-cell base station synchronous channel configuration method and a six-cell base station wireless system.

Referring to Figure 3, the general principle of configuring the cell synchronization channel by the base station is as follows:

1) The operation and maintenance center generates the corresponding relationship between each cell of the base station and the time offset parameter; that is, the operation and maintenance center provides a configuration scheme for a group of cell synchronization channels, and the corresponding relationship between each cell and the time offset parameter in this scheme may be based on the network Suggested values are given in the design. Usually in the configuration of the synchronization channel of the base station, when the operation and maintenance center proposes the corresponding relationship between each cell of the base station and the time offset parameter, no judgment is made on whether the corresponding relationship is reasonable or not;

2) The radio network controller judges the rationality of the corresponding relationship between each cell of the base station and the time offset parameter generated by the operation and maintenance center;

3) When the radio network controller judges that the corresponding relationship meets the configuration requirements of the base station synchronization channel, the radio network controller configures the time offset parameter of the base station, that is, it is used in the radio network controller to determine the synchronization channel of each cell of the base station The synchronization code corresponding to this parameter, and controls the base station to complete the configuration of the time offset parameter.

The method described in the invention solves the technical problem of synchronous channel configuration according to the networking characteristics of the mobile communication wireless network. Figure 4 is a schematic diagram of the coverage of 6 cells in a typical 6×1 base station. In order to ensure the continuity of services provided by the mobile communication system, there is a certain overlapping area between adjacent cells in the coverage area of the base station, so that the user terminal Soft handover can be realized when one cell enters another cell during communication. However, in the six-cell base station, not all six cells have overlapping coverage areas, as shown in the figure, cell 1, cell 3, and cell 5 have different coverage directions, and there is no overlapping coverage area; similarly, cell 2, cell 4 1. The coverage directions of cell 6 are different, and there is no overlapping coverage area.

From the above analysis, since the length of a time slot in the WCDMA system wireless frame structure is 2560 chips, and the length of the synchronization channel code in a time slot is 256 chips, the range of possible values for the parameter T cell is 10, That is, the value range of T cell is 0, 1, ..., 9. Therefore, a corresponding relationship between a cell and a time offset parameter that can meet the requirement that the time offset parameters of adjacent cells are not adjacent is as follows: there are three cells in the base station The time offset parameters of two non-adjacent cells are continuous, and the time offset parameters of other cells are spaced apart from each other, and are not adjacent to the above three continuous time offset parameters. The specific form of the corresponding relationship is: Time offset parameters corresponding to three non-adjacent cells The time offset parameters corresponding to the other three cells 0, 1, 2 4, 6, 8 1, 2, 3 5, 7, 9 2, 3, 4 6, 8, 0 3, 4, 5 7, 9, 1 4, 5, 6 8, 0, 2 5, 6, 7 9, 1, 3 6, 7, 8 0, 2, 4 7, 8, 9 1, 3, 5

Another configuration form in which the time offset parameters of adjacent cells are not adjacent is: The time offset parameters corresponding to the order of cells 1, 3, and 5 Time offset parameters corresponding to the sequence of 2, 4, and 6 cells 0, 1, 2 3, 4, 5 1, 2, 3 4, 5, 6 2, 3, 4 5, 6, 7 3, 4, 5 6, 7, 8 4, 5, 6 7, 8, 9 5, 6, 7 8, 9, 0 6, 7, 8 9, 0, 1 7, 8, 9 0, 1, 2

In the process of establishing the corresponding relationship between the cell and the time offset parameter, according to the difference in the coverage of each cell in the base station with 6×1 configuration (6 cells, one carrier frequency), an idea to realize the present invention is: The synchronization channels of the three covered cells are configured with three consecutive offset parameters, and the offset parameters configured by the other three cells should be discontinuous and not adjacent to the above three consecutive offset parameters. The idea is embodied in:

1) Select three consecutive time offset parameters in the time offset parameter field to configure three non-adjacent cells in the base station;

2) In the field, select time offset parameters that are spaced apart from each other and not adjacent to the three continuous time offset parameters, and configure synchronization channels of other cells in the base station.

According to the above idea of synchronous channel configuration of base stations of six cells, there are various specific implementation methods of synchronous channel configuration of base stations of six cells:

The configuration method described in the present invention is generally described as:

1) Divide all non-adjacent cells into one group. If the base station has a 6×1 configuration (6 cells with a single carrier frequency), then the base station has 6 cells, and the 6 cells can be divided into two groups. The first group is: cell 1, cell 3, cell 5, the second group is: cell 2, cell 4, cell 6;

2) Divide any three continuous time offset parameters in the time offset parameter domain into available time offset parameter groups, that is, select from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Three consecutive time offset parameters are enough to form a parameter group;

A set of remaining parameters in the domain is obtained by the constraints of the three consecutive time offset parameters, in which three are selected to be mutually spaced and not adjacent to the three continuous time offset parameters The time offset parameters of form another parameter group;

3) Select one parameter group to configure any cell group in the base station, and another parameter group to configure another base station cell group. During the configuration process, it is only necessary to ensure that the time offset parameters in the parameter group correspond to the cells in the configured cell group one by one There is no requirement for which cell the specific time offset parameter should be configured to.

The cell offset parameter can be a total of 10 values from 0 to 9, so the possible composition of the grouping described in step 2) is shown in the following table: 3 parameters in a row 3 arguments that are not consecutive 0, 1, 2 4, 6, 8 1, 2, 3 5, 7, 9 2, 3, 4 6, 8, 0 3, 4, 5 7, 9, 1 4, 5, 6 8, 0, 2 5, 6, 7 9, 1, 3 6, 7, 8 0, 2, 4 7, 8, 9 1, 3, 5

From the above, the present invention is realized in the WCDMA wireless access network equipment base station and base station controller. The base station controller configures different cell time offset parameters for different cells when the base station connected to it establishes a cell. According to the above embodiments, when the base station is configured in a 6×1 manner, the base station controller controls and implements the establishment of 6 cells in the base station. The configuration implementation steps are as follows:

1) The base station controller controls the configuration of the base station and establishes a cell;

2) When setting up numbered cell 1, set T_cell1=0;

3) When setting up numbered cell 2, set T_cell2=4;

4) When setting up numbered cell 3, set T_cell3=1;

5) When setting up numbered cell 4, set T_cell4=6;

6) When setting up numbered cell 5, set T_cell5=2;

7) When setting up numbered cell 6, set T_cell6=8;

8) The configuration of the 6×1 cell is completed.

The present invention also provides a six-cell base station wireless system obtained according to the six-cell base station configuration method described in the present invention.

The base station wireless system is composed of six cells, each cell includes a synchronization code, and the synchronization code is divided into a primary synchronization code and a secondary synchronization code. The primary synchronization code is transmitted once per time slot, and each cell in the system uses the same 256-chip spreading sequence; the code length of each secondary synchronization code is 256 chips, and different codeword combinations are used to identify different Code group sequence, a total of 64 different code groups can be used, and the slave synchronization code and the master synchronization code are sent in parallel. The primary synchronization codes of different cells all have time offsets, and the time offsets of the synchronization codes of adjacent cells are not adjacent. Furthermore, in the wireless system of the six-cell base station, the time offsets of the three non-adjacent cells in the base station are continuous, and the time offsets of the other three cells are spaced apart from each other, and none of them are consistent with the above-mentioned continuous time offsets. The three time offsets are adjacent.

Since the system is obtained according to the base station synchronization channel configuration method described in the present invention, an optimal mode of the corresponding relationship between the synchronization channel and the time offset of each cell in the system is: Time offset parameters corresponding to three non-adjacent cells The time offset parameters corresponding to the other three cells 0, 1, 2 4, 6, 8 1, 2, 3 5, 7, 9 2, 3, 4 6, 8, 0 3, 4, 5 7, 9, 1 4, 5, 6 8, 0, 2 5, 6, 7 9, 1, 3 6, 7, 8 0, 2, 4 7, 8, 9 1, 3, 5

Another way for each cell in the system to synchronize the relationship between the channel and the time offset is: The time offset parameters corresponding to the order of cells 1, 3, and 5 Time offset parameters corresponding to the sequence of 2, 4, and 6 cells 0, 1, 2 3, 4, 5 1, 2, 3 4, 5, 6 2, 3, 4 5, 6, 7 3, 4, 5 6, 7, 8 4, 5, 6 7, 8, 9 5, 6, 7 8, 9, 0 6, 7, 8 9, 0, 1 7, 8, 9 0, 1, 2

The six-cell base station synchronization channel configuration method and the six-cell base station wireless system provided by the present invention have been introduced in detail above. In this paper, specific examples have been used to illustrate the principle and implementation of the present invention. The descriptions of the above embodiments are only used to help Understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and scope of application. In summary, the content of this specification is not It should be understood as a limitation of the present invention.

Claims (8)

1, sub-district synchronous channel configuration method in a kind of six cell base station of six sector single carrier structure is characterized in that:

1) sets up each sub-district, base station and time migration parameter corresponding relation; The time migration parameter of neighbor cell is non-conterminous in this corresponding relation;

2) determine the synchronous code of sub-district synchronizing channel according to this corresponding relation.

2, sub-district synchronous channel configuration method in the six cell base station of six sector single carrier structure as claimed in claim 1 is characterized in that, the process of setting up corresponding relation described in the step 1) is specially:

1) three mutual non-conterminous sub-districts in three continuous parameter respective base station in the access time of the offset parameter territory;

2) in described territory, choose the space and with described three non-conterminous parameters of continuous parameter to its excess-three sub-district in should the base station.

3, sub-district synchronous channel configuration method in the six cell base station of six sector single carrier structure as claimed in claim 1 or 2, it is characterized in that, described corresponding relation is specially: the time migration continuous parameters of three mutual non-conterminous sub-districts in the base station, the time migration parameter space of other three sub-districts, and not adjacent with described three continuous time migration parameters.

4, sub-district synchronous channel configuration method in the six cell base station of six sector single carrier structure as claimed in claim 3 is characterized in that, described corresponding relation is:

Three mutual non-conterminous sub-district time corresponding parameters are 0,1,2, and the time migration parameter of three sub-districts is 4,6,8 in addition;

Three mutual non-conterminous sub-district time corresponding parameters are 1,2,3, and the time migration parameter of three sub-districts is 5,7,9 in addition;

Three mutual non-conterminous sub-district time corresponding parameters are 2,3,4, and the time migration parameter of three sub-districts is 6,8,0 in addition;

Three mutual non-conterminous sub-district time corresponding parameters are 3,4,5, and the time migration parameter of three sub-districts is 7,9,1 in addition;

Three mutual non-conterminous sub-district time corresponding parameters are 4,5,6, and the time migration parameter of three sub-districts is 8,0,2 in addition;

Three mutual non-conterminous sub-district time corresponding parameters are 5,6,7, and the time migration parameter of three sub-districts is 9,1,3 in addition;

Three mutual non-conterminous sub-district time corresponding parameters are 6,7,8, and the time migration parameter of three sub-districts is 0,2,4 in addition;

Three mutual non-conterminous sub-district time corresponding parameters are 7,8,9, and the time migration parameter of three sub-districts is 1,3,5 in addition.

5, sub-district synchronous channel configuration method in the six cell base station of six sector single carrier structure as claimed in claim 1 or 2, its feature in: the corresponding length of described time migration parameter is the synchronous code of 256 chips.

6, a kind of six cell base station wireless system that obtains according to the described method of claim 1, each base station system is the system of six cell base station that six sectors constitute the single carrier configuration structure, its feature in: the time migration parameter of neighbor cell is non-conterminous in the system.

7, six cell base station wireless system as claimed in claim 6, its feature in, non-conterminous being specially of neighbor cell time migration parameter in the described system: the time migration continuous parameters of three mutual non-conterminous sub-districts in the system, the time migration parameter space of its excess-three sub-district, and not adjacent with described three continuous time migration parameters.

8, as claim 6 or 7 described six cell base station wireless systems, its feature in: the corresponding length of described time migration parameter is the synchronous code of 256 chips.

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