Abstract-Joint power control and beamforming schemes are proposed for cellular systems where adaptive arrays are used only at base stations. In the uplink, mobile powers and receiver diversity combining vectors at base stations are calculated jointly. The mobile transmitted power is minimized, while the signal-tointerference-and-noise ratio (SINR) at each link is maintained above a threshold. A transmit diversity scheme for the downlink is also proposed where the transmit weight vectors and downlink power allocations are jointly calculated such that the SINR at each mobile is above a target value. The proposed algorithm achieves a feasible solution for the downlink if there is one and minimizes the total transmitted power in the network. In a reciprocal network it can be implemented in a decentralized system, and it does not require global channel response measurements. In a nonreciprocal network, where the uplink and downlink channel responses are different, the proposed transmit beamforming algorithm needs to be implemented in a centralized system, and it requires the knowledge of the downlink channel responses. The performances of these algorithms are compared with previously proposed algorithms through numerical studies. Index Terms-Adaptive arrays, downlink beamforming, power control, transmit beamforming.
Another early work, REF , considered joint optimization of power and beamforming vectors for the DL of a multiple antenna cellular system employing a simple linear transmission strategy followed by single user receivers, such that the SINR at each mobile is above a target value; the proposed algorithm achieves a feasible solution for the DL if there is one and minimizes the total transmit power in the network.
Transmit beamforming and power control for cellular wireless systems
IEEE J. Sel. Areas Commun
Computer Science