Method for constituting structure of time slot of DwPCH and UpPCH in TD SCDMA system

[0015] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0016] figure 1 It is a schematic diagram of the subframe structure of a normal TD-SCDMA system, where: the number of chips occupied by each time slot is marked on the figure; TS0 and DwPTS are constant for downlink; UpPTS and TS1 are constant for uplink.

[0017] figure 2 It is a schematic diagram of the structure of DwPTS in the usual TD-SCDMA system protocol, image 3 It is a schematic diagram of the composition structure of the DwPTS proposed by the present invention. As shown in the figure, in the DwPTS composition structure proposed by the present invention, the SYNC_DL of 64 chips is placed before the guard interval of 32 chips.

[0018] Figure 4 It is a schematic diagram of the composition structure of UpPTS in the TD-SCDMA system protocol, Figure 5 It is a schematic diagram of the composition structure of UpPTS proposed by the present invention. As shown in the figure, in the UpPTS composition structure proposed by the present invention, the SYNC_UL of 128 chips is placed between two guard intervals, and there is a guard interval of 16 chips before and after the SYNC_UL.

[0019] Figure 6 It is a schematic diagram of the comparison between the SYNC_DL and SYNC_UL intervals in the usual TD-SCDMA system and the SYNC_DL and SYNC_UL intervals in the present invention. As shown in the figure, compared with the structure proposed in the TD-SCDMA system protocol, the interval between SYNC_DL and SYNC_UL in the structure proposed by the present invention is increased from 96 chips to 144 chips, but the total number of chips remains unchanged.

[0020] Figure 7 It is a table of the initial UpPCH call strategy initiated to the current UE in the present invention. In order to avoid uplink UpPCH to other UE’s uplink services in TS1 as much as possible, the current UE initiates the initial UpPCH call according to Figure 7 Strategy processing:

[0021] Step 1: Divide all possible coverage ranges from 0 to 16.88Km into 18 levels, and classify them into one and two categories from the largest to the smallest. The first class has a higher priority than the second class;

[0022] Step 2: UE first try TADV from big to small in class 1, and gradually increase the transmit power of UpPTS according to protocol [2] to try; (protocol [2] refers to 3GPP TS 25.331,'RadioResource Control (RRC) ; Protocol Specification', release4, V.4.15.0, 2004-6)

[0023] Step 3: Only if the connection is not successful after trying class one, try class two again, the method is the same as step two above.

[0024] In summary, the present invention changes the distribution position of the protection chips in the DwPCH and UpPCH in the usual TD-SCDMA system, increases the guard interval between SYNC_DL and SYNC_UL, and the guard interval between SYNC_DL and SYNC_UL is changed from the 96chips in the current TD-SCDMA protocol. Increased to 144chips, according to the calculation of the transmission delay, the coverage of 16.88Km can be obtained, which is 50% larger than the original 11.25Km. Improve the coverage of the cell in the TD-SCDMA system by about 50%. At the same time, the TD-SCDMA system frame structure in the present invention does not increase the number of extra chips, does not affect the processing of the UE and the Node B, and does not increase the processing delay of the UE and the Node B.