FlexRadio: Fully Flexible Radios and Networks

When a wireless node has multiple RF chains, there are several techniques that are possible; MIMO, full-duplex and interference alignment. This paper aims to unify these techniques into a single wireless node. It proposes to make a wireless node fully flexible such that it can choose any number of its RF chains for transmission and the remaining for simultaneous reception. Thus, MIMO and full duplex are subset configurations in our design. Surprisingly, this flexibility performs better than MIMO or full duplex or interference alignment or multi-user MIMO.

This paper presents the design and implementation of FlexRadio, the first system enabling flexible RF resource allocation. We implement FlexRadio on the NI PXIe 1082 platform using XCVR2450 radio front-ends. FlexRadio node networks achieves a median gain of 47% and 38% over same networks with full duplex and MIMO nodes respectively.