Amplifiers – Hum or noise or distortion bucking introduced into signal...
Patent
1993-11-30
1995-06-13
Mullins, James B.
Amplifiers
Hum or noise or distortion bucking introduced into signal...
359153, 359161, 327317, 327133, H03F 132
Patent
active
054246806
ABSTRACT:
A generalized frequency dependent predistortion circuit for nonlinear optic devices such as semiconductor lasers and light emitting diodes includes a pre-filter and post-filter associated with a linearizer (distorter). A multi-channel sub-carrier electrical signal is input to a splitter which provides on a primary path a signal to a time delay and hence to a coupler to the secondary paths. In the first secondary path, a pre-filter provides a signal to a second order distorter. This signal is then subject to a post-filter and then to a variable attenuator. In the second secondary path, a third order distorter again has an associated pre-filter and post-filter with a variable attenuator downstream of the post-filter. The variable attenuators in each path provide frequency independent attenuation. In one version the distorters in both paths are nonlinear diode circuits. The second secondary path provides very low fundamental leak-through. The pre- and post-filters are of similar design with differing component values, each filter being an integral equalizing filter which arbitrarily manipulates phase and amplitude in a frequency dependent fashion. Each is a synthesized filter tuned or built to a specific complex frequency-dependent profile to linearize a particular individual laser unit.
REFERENCES:
patent: 4068186 (1978-01-01), Sato et al.
patent: 4329655 (1982-05-01), Nojima et al.
patent: 4992754 (1991-02-01), Blauvelt et al.
patent: 5127072 (1992-06-01), Blauvelt et al.
patent: 5132639 (1992-07-01), Blauvelt et al.
patent: 5172068 (1992-12-01), Childs
patent: 5179461 (1993-01-01), Blauvelt et al.
patent: 5252930 (1993-10-01), Blauvelt
H. M. Achor, "An Invertible Volterra Model of Second-Order Distortion in DFB Lasers", IEE Photonics Technology Letters, vol. 5, No. 3, Mar. 1993, pp. 294-297.
Toshio Nojima et al., "Predistortion Nonlinear Compensator for Microwave SSB-AM System", Electronics and Communications in Japan, vol. 67-B, No. 5, 1984, pp. 57-66.
IEEE Photonics Letters, vol. 4, No. 7, Jul. 1992, p. 792.
I. V. Kalmykov et al., "A Method of Compensating the Nonlinear Distortions of Light-Emitting and Laser Diodes in Broadband Analog Communications Systems", originally publishedin Radiotekhnika, No. 6, 1989, pp. 77-79.
Manfred Bertelsmeier et al., "Linearization of Broadband Optical Transmission Systems by Adaptive Predistortion", Freguenz, 38(1984)9, pp. 206-212.
Gall Charles H.
Kuo Chien-Yu
Nazarathy Moshe
Harmonic Lightwaves, Inc.
Klivans Norman R.
Mullins James B.
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