Small form factor wireless communication relays with low physical isolation configured for adjacent channel and co-channel operation

Abstract

A wireless communications relay includes a first radio and a second radio operating over adjacent channels. A baseband signal to be transmitted (the 'transmit signal') from the first radio is split along two paths. A first path is delayed by a delay element and the second path is provided as input to a channel model configured to implement a transfer function approximating an echo channel of the local RF environment. The channel model outputs a baseband approximation of echo channel effects of the transmit signal, after which an RF chain modulates the echo channel approximation to the RF domain. This RF echo channel approximation is thereafter filtered by an RF band pass filter turned to an operating channel of the second radio. The filtered signal is thereafter combined with received signal to compensate for self-interference.