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 fedback optical signal that is more than 200 dB below the transmitted power level has been achieved.
© 1987 Optical Society of America
Original Manuscript: February 6, 1987
Manuscript Accepted: April 25, 1987
Published: August 1, 1987
J. Fred Holmes, Farzin Amzajerdian, and John M. Hunt, "Improved optical local-oscillator isolation using multiple acousto-optic modulators and frequency diversity," Opt. Lett. 12, 637-639 (1987)