US 7,466,929 B2
Method and system for superheterodyne detection of an optical input signal
Douglas M. Baney, Los Altos, Calif. (US); Tun S. Tan, Redwood City, Calif. (US); and Bogdan Szafraniec, Sunnyvale, Calif. (US)
Assigned to Agilent Technologies, Inc., Santa Clara, Calif. (US)
Filed on Mar. 11, 2004, as Appl. No. 10/800,073.
Prior Publication US 2005/0202793 A1, Sep. 15, 2005
This patent is subject to a terminal disclaimer.
Int. Cl. H04B 10/06 (2006.01)
U.S. Cl. 398—204  [398/202; 398/203; 398/205; 398/206; 398/207; 398/208; 398/209; 398/213; 398/214; 356/484; 356/451; 356/477; 356/73.1; 250/214 R; 250/227.27; 250/227.19; 250/227.17] 20 Claims
OG exemplary drawing
 
1. A system for superheterodyne detection comprising:
a first conversion unit for performing a first heterodyne operation on an optical input signal to generate an electrical IF signal, the first conversion unit comprising i) a local oscillator for generating a swept local oscillator signal, ii) a coupler for coupling said optical input signal and said swept local oscillator signal, and ii) a photodetector; and
a second conversion unit, electrically coupled to said first conversion unit, comprising i) an electrical local oscillator for generating a fixed electrical local oscillator signal, and ii) a mixer coupled to said electrical local oscillator for performing a second heterodyne operation by mixing said electrical IF signal and said fixed electrical local oscillator signal to generate an electrical output signal suitable for signal processing.