US Patent 7164738 Signal canceling method and device

In a signal cancellation method and device which can cancel input signals quickly and reliably (stably), an input signal is split into a first and second signal. The second signal is split into mutually orthogonal first and second subsignals which are recombined after the respective amplitudes thereof have been adjusted, The first signal is canceled by the third signal thereby obtained. The orthogonal subsignals can undergo amplitude adjustment independently, and the third signal obtained by recombining the subsignals after adjustment can become a cancellation signal having a really selected phase and amplitude over the first through fourth quadrants of the vector plane.