The Research On Handoff Of CDMA Systems

In CDMA system, the quality of service(QoS) of each MS becomes more important with the increase of the number of MS. To guarantee well QoS, handoff is the key link, which is also an important part of mobile management. The handoff technique, the channel of MS can be switched to another Base station, which prevents the communication from interruption when mobile customer strides across one BS. Handoff can improve utilization ratio of system resources, also obtaining higher performance of system. Handoff is the most complicated and vital technique in CDMA system.The paper focuses on the handoff of CDMA systems. Firstly, the principle of CDMA and its key techniques are briefly introduced. Secondly, the conception, types and several typical schemes of handoff are briefly outlined. Also, Markov chain is applied to analyze and simulate several typical handoff schemes. At last, this paper concentrates on soft handoff technique, analyze the performance of soft handoff under different conditions of mobile customers'various speed in CDMA system.In CDMA system, the MS'speed is one important factor of performance of soft handoff. The paper is mainly about research and analysis of handoff in CDMA system and specifically analyzes the influence of mobile customer'speed on various parameters of soft handoff. Based on square mathematical soft handoff model, the paper lead soft handoff traffic parameters, and analyzes the impact of the size of soft handoff area and mobile customers'speed on the parameters of soft handoff, making numerical analysis and simulating parameters of soft handoff under different mobile customers'speed. It is found that the performance of system can be optimized by changing the SR in CDMA system. The research of paper is not only provides theory valuable, but also offer certain reference for practical practice implications.