RadMAC: radar-enabled link obstruction avoidance for agile mm-wave beamsteering

ABSTRACT

Millimeter-wave (mm-wave) communication technology can provide multi-Gbps connectivity but directional mm-wave links are easily blocked by moving obstacles, e.g. humans, common in indoor environments. Seamless high speed data provisioning thus necessitates timely beamsteering to secondary reflected links in case of primary link obstruction. Making smart beam-switching decisions requires superior environment awareness, to predict and avoid link obstruction. We propose the novel concept of radar-enhanced mm-wave medium access --- RadMAC --- where radar is integrated with the mm-wave link to locate and track moving obstacles and avoid link disruption by preemptively switching to the best available unblocked link. We experimentally demonstrate the benefit of obstacle-tracking radar for agile mm-wave beamsteering, showing RadMAC can significantly enhance throughput and link stability. We argue that practical RadMAC implementation will be feasible using emerging single-chip mm-wave radar and communications solutions.

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