Research On HSUPA Scheduling Algorithm In WCDMA Systerm

In the evolution of WCDMA standard, in order to improve data transmission capacity, 3GPP proposed High Speed Uplink Packet Access (HSUPA) in the R6 version. With several pivotal technologies such as Hybrid Automatic repeat Request technology (HARQ), shorter Transmission Time Interval (TTI), fast scheduling based on the base station, soft switch and so on , HSUPA made users' feelings better and further improved network uplink performance, accordingly providing higher uplink data rate and lower delay for emerging data services.This paper first studies 5 new physical channels of HSUPA closely related with scheduling, including 2 uplink channels(E-DPDCH and E-DPCCH) and 3 downlink channels(E-AGCH, E-RGCH and E-HICH). Secondly, by analyzing the limit capacity of the cell, the effective E(/No concept is proposed with which the condition for obtaining HARQ retransmission gain is deduced accordingly. Furthermore, by studying on HSUPA MAC layer scheduling, an improved retransmission merging algorithm is put forward based on N-channel Stop-and-Wait HARQ retransmission mechanism. In the last part of this paper, various test results and simulation curves corresponding to different data block sizes are shown and compared. It is verified that in the case of 10ms TTI, single antenna and AWGN, retransmission merging algorithm could greatly reduce the single user uplink ber, thereby improving the system throughput.