Patent ID: 6047306
Filing Date: 2000-04-04
Classification: G06G,H04B

Abstract:
A surface acoustic wave signal processing apparatus for processing first and second high-frequency signals having frequencies f.sub.1 and f.sub.2 respectively, wherein said first high-frequency signal is a modulated wave signal and said second high-frequency signal is a non-modulated wave signal, which comprises:first and second surface acoustic wave delay elements for receiving said first and second high frequency signals respectively and independently of each other, said delay elements being formed as surface acoustic wave excitation and reception transducers on a piezoelectric substrate so that a phase delay .phi..sub.1 with respect to the frequency f.sub.1 is substantially equal to a phase delay .phi..sub.2 with respect to the frequency f.sub.2 (that is, .phi..sub.1 .apprxeq..phi..sub.2); anda mixer for mixing first and second high-frequency output signals of said first and second surface acoustic wave delay elements so that a signal having a frequency .vertline.f.sub.1 -f.sub.2 .vertline. which is a difference between said two frequencies f.sub.1 and f.sub.2 is taken out as an output signal of said mixer.