Continuous aperture phased MIMO: Basic theory and applications

Given the proliferation of wireless communication devices, the need for increased power and bandwidth efficiency in emerging technologies is getting ever more pronounced. Two technological trends offer new opportunities for addressing these challenges: mm-wave systems (60-100GHz) that afford large bandwidths, and multi-antenna (MIMO) transceivers that exploit the spatial dimension. In particular, there has been significant recent interest in mm-wave communication systems for high-rate (1-100 Gb/s) communication over line-of-sight (LoS) channels. Two competing designs dominate the state-of-the-art: i) traditional systems that employ continuous aperture “dish” antennas and offer high power efficiency but no spatial multiplexing gain, and ii) MIMO systems that use discrete antenna arrays for a higher multiplexing gain but suffer from power efficiency. In this paper, we propose a new communication architecture - continuous aperture phased MIMO - that combines the advantages of both designs and promises very significant capacity gains, and commensurate gains in power and bandwidth efficiency, compared to the state-of-the-art. CAP-MIMO is based on a hybrid analog-digital transceiver architecture that employs a novel antenna array structure - a high-resolution discrete lens array - to enable a continuous aperture phased-MIMO operation. We present the basic theory behind CAP-MIMO and the potential capacity/power gains afforded by it. We also highlight potential applications of CAP-MIMO in mm-wave communications.