Improved optical local-oscillator isolation using multiple acousto-optic modulators and frequency diversity.
A technique is described and experimental evidence presented for obtaining ultrahigh isolation between the optical local oscillator and the transmitter in heterodyne systems. A degree of isolation that results in an equivalent fed-back optical signal that is more than 200 dB below the transmitted power level has been achieved.
Holmes
J F
JF
Department of Applied Physics and Electrical Engineering, Oregon Graduate Center, 19600 N.W. Von Neumann Drive, Beaverton, Oregon 97006-1999, USA.
Amzajerdian
F
F
Hunt
J M
JM