Time-Slotted Round-Trip Carrier Synchronization for Distributed Beamforming

Transmit beamforming is an energy-efficient wireless communication technique that allows a transmitter with two or more antennas to focus its bandpass signal in an intended direction. Recently, the idea of transmit beamforming has been extended to networks of single-antenna cooperative transmitters that pool their antenna resources and behave as a "distributed beamformer." Unlike conventional transmit beamforming, however, the carriers of the single-antenna transmitters in a distributed beamformer are each synthesized from independent and imperfect local oscillators; carrier phase and frequency synchronization among the transmitters is necessary to ensure that a beam is aimed in the desired direction. In this paper, a new time-slotted round-trip carrier synchronization protocol is proposed to enable distributed beamforming in multiuser wireless communication systems. Numerical results for a distributed beamformer with two transmitters show that the parameters of the round-tri...

• Type: Journal
• Year: 2008
• Where: TSP
• Authors: D. Richard Brown III, H. Vincent Poor
• Keywords: Beamforming, Distributed Beamformer, Transmitters, TSP 2008