Performance of VoIP in HSDPA based on an adaptive power allocation scheme

In the HSDPA system, code multiplexing in one TTI is required to transmit packets for multiple VoIP users. This paper proposes an adaptive power allocation (APA) scheme for code multiplexing. The proposed APA scheme adaptively allocates the transmit power to each user in downlink according to the user's link status. The user capacity in the HSDPA system based on the proposed APA scheme is compared with that of the conventional equal power allocation (EPA) scheme through simulation. The simulation results show that the user capacity of HSDPA based on the proposed APA scheme is 136, compared to 75 of the conventional EPA scheme