Data Rate Throughput Increase Using Super-Resolution Beamforming

摘要

A fundamental goal of wireless communications system's designers is to maximize the spectral efficiency of transmission. In the systems presented here, this is achieved through the use of transmitters and receivers equipped with multi-antenna systems. While some multi-antenna techniques may be appropriately classified as either Multiple Input Multiple Output (MIMO) or alternatively as beamforming solutions, the methods presented here do not fall conveniently into either of those categories. MIMO systems are often designed for operation in multipath rich environments, in contrast to our system which works preferably with LOS channels (though it can operate in time dispersive multipath environments with more complex receivers). On the other hand, beamforming systems are usually designed to have geographically distributed receivers and/or transmitters. In the system presented here, the transmitter antennas are collocated and the receiver antennas are also collocated. Consequently our "beams" must be extremely narrow to select and null antennas which are essentially collocated. Simulation results are presented which use two 64 QAM signals. Impairments such as motion, caused for example by wind distortion of the antenna masts, and time dispersion, caused by a multipath propagation channel are included. Experimental results using a 64 QAM and a 16 QAM signal are also presented for LOS channels.