This paper proposes a new algorithm to control an adaptive duplexer for multiband software radio. It uses a wideband low isolation device combined with a two-tap/two-loop adjustable canceller to eliminate the need for multiple switched high isolation duplexers. The taps are adjusted to provide isolation peaks in the transmit and receive bands. The algorithm is based on the superposition of squared errors and achieved 66 dB isolation of the transmit signal and a 37 dB cancellation of the transmitter noise in the receiver band.

A novel reconfigurable architecture has been proposed for a mobile terminal receiver that can drastically reduce power dissipation dependant on adjacent channel interference. The proposed design can automatically scale the number of filter coefficients and word length respectively by monitoring the in-band and out-of-band powers. The new architecture performance was evaluated in a simulation UTRA-TDD environment because of the large near far problem caused by adjacent channel interference from adjacent mobiles and base stations. The UTRA-TDD downlink mode was examined statistically and results show that the reconfigurable architectures can save an average of up to 75% power dissipation respectively when compared to a fixed filter length of 57 and word length of 16 bits. This power saving only applies to the filter and ADC, not the whole receiver. This will prolong talk and standby time in a mobile terminal. The average number of taps and bits were calculated to be 14.98 and 10 respectively, for an outage of 97%.