Forward link smart antennas and power control for IS-136

Abstract

We study the increase in range using smart antennas and transmit power allocation between beams on the forward link in IS-136. We consider the increase with fixed-beam antennas in low angular-spread environments, with transmit allocation between beams with a total transmit constraint. We compare the performance with a continuous downlink to that with a discontinuous downlink. With a total transmit power constraint, results show that the beamforming technique with a continuous downlink requires about 2 to 3 dB more peak transmit power than with a discontinuous downlink for the same coverage with four beams. Thus, most of the improvement of smart antennas and power control can be achieved even with the continuous downlink constraint by appropriate beamforming. Furthermore, with a handset performance loss with a discontinuous downlink of about 4 dB, the use of a discontinuous downlink with today's handsets will not result in an in performance even with smart antennas.