  Recently, several advanced multi-antenna radio communications technologies
have emerged to meet the increased capacity demands in wireless multi-user
networks. Despite their great potential, the extent of these techniques'
practical applicability still remains questionable, since they have to face
either backhaul limitations or cost and hardware constraints. In this paper, we
propose a new system solution which includes network architecture, antenna
technology and radio transmission protocol to reduce drastically the hardware
complexity and cost as well as the channel state information / user data
feedback requirements of multi-user multi-antenna wireless networks. We focus
on the forward link of an interference channel in a cloud radio access network
setup wherein an arbitrary number of remote radio heads are each equipped with
a single radio frequency module parasitic antenna array and wish to send data
to their respective single-antenna user terminals, while co-existing in time
and frequency. Base stations select cooperatively the optimal combination of
pre-determined beams prior transmission. Our proposed approach is able to
achieve the aforementioned goals, while offering significant downlink sum-rate
gains due to the available spatial degrees of freedom.
