Distributed spatial multiplexing with 1-bit feedback

— We analyze the feasibility of distributed spatial multiplexing with limited feedback in a slow-fading interference network with MN non-cooperating single-antenna sources and M non-cooperating single-antenna destinations. In particular, we assume that the sources are divided into M mutually exclusive groups of N sources each, every group is dedicated to transmit a common message to a unique destination, all transmissions occur concurrently and in the same frequency band and a dedicated 1-bit broadcast feedback channel from each destination to its corresponding group of sources exists. We provide a feedback-based iterative distributed (multi-user) beamforming algorithm, which “learns” the channels between each group of sources and its assigned destination. This algorithm is a straightforward generalization, to the multi-user case, of the feedback-based iterative distributed beamforming algorithm proposed recently by Mudumbai, Hespanha, Madhow and Barriac in [1] for networks with ...

• Type: Journal
• Year: 2007
• Where: CORR
• Authors: J. Thukral, Helmut Bölcskei
• Keywords: Algorithm, CORR 2007, Education, Multiplexing, Spatial Multiplexing Gain