高速分组数据系统中一种自适应速率控制算法

Proposing a Novel Adaptive Rate Control Algorithm for Application to Forward Link of High Rate Packet Data(HRPD) Wireless System

3G-1x EVDO系统是一种可以向移动用户提供高速分组数据业务的系统。将信道自适应技术引入到该系统中,提出了一种适合该系统前向链路数据传输的自适应速率控制算法。仿真结果表明:在时变信道环境下,自适应算法的吞吐量性能优于基于门限的固定余量算法,而接近于最优速率控制方法。

Aim. IS-856 standards stipulates minimum performance requirements that HRPD mobile terminal must satisfy, we now propose a novel adaptive control algorithm that appears to be a good way of meeting these minimum requirements. In the full paper, we explain our novel algorithm in detail ;in this abstract, we just add some pertinent remarks to listing the one topic of explanation： （1） adaptive rate control algorithm; the three subtopics of topic 1 are the fixed margin data rate selection method （subtopic 1.1）, optimal rate control algorithm （subtopic 1.2）, and adaptive rate control algorithm （subtopic 1.3）; in subtopic 1.1, we review the fixed margin data rate selection method widely used in the forward link of HRPD; in subtopic 1.2, we point out that although optimal rate control is ideal but it is very difficult to implement; in subtopic 1.3, we propose our adaptive rate control algorithm that is not ideal but is easy to implement and can give results that are only somewhat inferior to those obtained with optimal rate control; our algorithm is based on channel adaptive techniques; also, in subtopic 1.3, after each DRC（data rate control） interval, our algorithm adaptively adjusts the Ec/N, thresholds by performing five operations explained in detail in the full paper. Finally, our simulation results are given in Fig. 2 and Table 3 in the full paper. From Fig. 2 and Table 3 we can see that the throughputs of our adaptive rate control algorithm are only 1%-13% less than those obtained with optimal rate control.