On the feasibility of spatial multiplexing for indoor 60 GHz communication

ABSTRACTWe investigate spatial multiplexing in the sparse multipath environment characteristic of beamsteered indoor 60 GHz links. The small carrier wavelength implies that large spatial multiplexing gains are available even under line of sight (LOS) conditions for nodes with form factors compatible with consumer electronics devices such as set-top boxes and television sets. We present a transceiver architecture that provides both highly directive beams and spatial multiplexing, and model its performance for a typical in-room communication link. We evaluate the performance of a simple scheme using a fixed constellation, transmit beamsteering and MMSE reception. The performance is benchmarked against transmit precoding along the channel eigenmodes without a constellation constraint. We observe that, for a relatively small transmit power per antenna element (achievable, for example, in low-cost CMOS processes), the spatial multiplexing gain is robust to LOS blockage and to variations in the relative locations of the transmitter and receiver in the room.