In this paper, performance analysis of packet scheduling schemes is discussed and an efficient packet scheduling scheme is proposed in a multicode WCDMA/TDD system for different data rate users. The multicode CDMA was originally proposed as a technique to provide variable rate services by assigning variable number of codes to users with a constant spreading gain. Given a fixed spreading factor, multicode allocation schemes for packet transmission with different data rate service are investigated. The objective of the proposed scheme is to improve system performance in terms of throughput, blocking probability, dropping probability and fairness.
The proposed scheme is mainly focused on delay control and gives priority to on-going users. Delay control decreases the blocking probability and provides fairness to users. Priority to on-going users prevents packets from discarding users in transmission. Implemented with SIR estimation, the proposed scheme provides better throughput. The cost of these improvement is buffer size increase due to longer average delay of packets. However, low dropping probability and blocking probability show that the proposed scheme provides robust services.