Kernel Adaptive Filters: A Panacea for Self-interference Cancellation in Mobile Communication Transceivers?

In frequency division duplex transceivers, the non-ideal analog duplexer has only a limited stop-band attenuation, and therefore a part of the transmit signal leaks into the receive path. Although operating on a different frequency band, non-ideal effects in the receive path cause different kinds of self-interferences, which can have a higher power level than the actual wanted receive signal. A possible way to tackle this problem are adaptive filters. These approaches are mostly model based, and for each kind of interference a different algorithm is needed. Kernel adaptive filtering offers the possibility to deal with different sorts of interferences with the same algorithm. In this work, we investigate the capabilities of kernel adaptive filtering to cancel especially the second-order intermodulation distortion (IMD2) and the transmitter (Tx)-harmonics interference.