Abstract: An optical receiver communication system converts optical signals modulated by analog or digital waveforms to RF signals. The optical receiver contains an automatic level control circuit to adjust the electronic gain of the system across a broad bandwidth spectrum. Two impedance matching circuits are designed using broad band matching technique to expand the bandwidth for increasing the maximum receivable frequencies to 1 GHz. A RLC impedance matching circuit forms a resonant combination to maintain .+-.1 dB fluctuation between the low-and-high-frequency limits of the bandwidth, and a 75.OMEGA. impedance matching circuit creates a 180.degree. phase shift between outgoing and incoming signals to ensure low return loss.
Type:
Grant
Filed:
January 6, 1997
Date of Patent:
May 25, 1999
Assignee:
Qualop Systems Corp.
Inventors:
Ching Ho, Yue-Syan Jou, Chun-Meng Su, Peter Wang, Yong Cheng Tu