A Self-Interference Cancellation Testbed for Full-Duplex Transceiver Prototyping

In-Band Full Duplex (IBFD) transceivers can potentially provide significant increases in spectral efficiency by allowing simultaneous transmit and receive on the same frequency at the same time. However any such gains are conditional on effective cancellation of the self-interference. The performance of a self-interference cancellation transceiver depends not only on the system design, but also on implementation specific parameters of the transceiver and cancellation circuitry. Thus, realistic evaluation of cancellation performance can only be performed using hardware prototypes. This paper provides a detailed overview of a highly flexible and reconfigurable self-interference cancellation testbed, which combines active cancellation with either separate Tx and Rx antennas, or an Electrical Balance Duplexer, along with digital baseband cancellation. The system can facilitate investigation on self-interference cancellation performance across a range of physical layer configurations, and provide a platform for the rapid prototyping of digital baseband algorithms within an operational self-interference cancelling transceiver.