Access control of data in integrated voice/data CDMA systems: benefits and tradeoffs

In previous work, access control for data was proposed as a method to enhance capacity while ensuring adequate quality of service (QoS) in an integrated voice/data CDMA system. The motivation behind access control is to schedule data packet transmissions when voice activity is low and curtail data transmissions when the voice load is heavy. In this work, a simple and flexible real-time access control scheme proposed in previous work, is extended. The performance measures used are the probability of outage and delay for data. It is shown how the system can support more users with access control than without, for a given probability of outage. The penalty lies in introducing delay for the data users. Performance of the control schemes is analyzed for different parameters and tradeoffs involved in their choice are discussed. It is demonstrated that with appropriate choice of parameters, the proposed real-time control scheme approaches the performance of optimum prediction schemes, in terms of the tradeoff between capacity and delay