Optimal power allocation for a multi-rate packet CDMA system with multi-media traffic

Usually, when combining two or more services (each having their own QoS requirements), it is difficult to achieve a common operation point for all the services, When we satisfy the highest QoS requirement, the other services will be operating at “unnecessary high quality”. In this case, a lot of bandwidth is wasted due to a low traffic load. To solve this problem and to achieve higher spectral efficiency, a “QoS balance” method is developed in this paper to optimise the allocation of transmission power and evaluated in a wide-band DS-CDMA environment integrated with video and voice services. Our simulation results demonstrate that the capacity of the network or spectral efficiency is improved significantly, by this optimal power allocation scheme