Multi-objective optimization power control for code division multiple access systems

摘要

In code division multiple access (CDMA) communication systems, the communication channel is usually corrupted with time-varying interferences, which include channel fading, multiple access interference, round-trip delay, and noise. Power control is an important issue for CDMA systems to achieve higher communication link quality and better system capacity under time-varying interferences. In the previous studies, most of power control algorithms only considered the user's target signal-to-interference-and-noise-ratio (SINR) to maintain quality of service. In this study, a multi-objective optimization method is proposed for power control design in CDMA systems. With a shadow system and an H_∞ filter to compensate for the round-trip delay, the proposed power control scheme can simply adjust transmission power to achieve the best compromise between several objectives, such as minimization of SINR deviation, minimization of power consumption, and minimization of the system outage. Several simulation results are given to confirm the performance of the proposed power control scheme.