Control Channel Design for Many-Antenna MU-MIMO

Many-antenna MU-MIMO faces a critical, previously unaddressed challenge: it lacks a practical control channel. At the heart of this challenge is that the potential range of MUMIMO beamforming systems scales with up to the square of the number of base-station antennas once they have channel state information (CSI), whereas the range of traditional control channel operations remains constant since they take place before or during CSI acquisition. This range gap between no-CSI and CSI modes presents a critical challenge to the efficiency and feasibility of many-antenna base stations, as their operational range is limited to the no-CSI mode. We present a novel control channel design for many-antenna MU-MIMO, Faros, that allows the number of base-station antennas to scale up to 100s in practice. Faros leverages a combination of open-loop beamforming and coding gains to bridge the range gap between the CSI and no-CSI modes. Not only does Faros provide an elegant and efficient control channe...

• Type: Journal
• Year: 2015
• Where: MOBICOM
• Authors: Clayton Shepard, Abeer Javed, Lin Zhong
• Keywords: Communications, MOBICOM 2015