Telecommunications – Receiver or analog modulated signal frequency converter – Modulation distortion or cross talk correction or elimination
Patent
1978-03-29
1980-09-02
Griffin, Robert L.
Telecommunications
Receiver or analog modulated signal frequency converter
Modulation distortion or cross talk correction or elimination
324 57N, 333 18, 333166, 455 63, 375 58, 375101, 328167, H04B 110
Patent
active
042209234
ABSTRACT:
An adaptive interference reduction system for removing cross talk from a dual polarization system comprising a first adjustable filter for varying the phase and the weight of a first input signal, a second adjustable filter for varying the phase and the weight of a second input signal, a first adder for adding this first input signal and the weighted and phase adjusted output from the second adjustable filter, a second adder for adding the second input signal and the weighted and phase adjusted output from the first adjustable filter, a first noise-to-signal measuring device for generating a signal proportional to the noise-to-signal ratio in the output signal from the first adder, a second noise-to-signal measuring device for generating a signal proportional to the noise-to-signal ratio in the output signal from the second adder, and a dither-type control logic for dithering in-phase and quadrature square-waves in accordance with the signals generated by the first and second noise-to-signal measuring devices to control the first and second adjustable filters. This system is further characterized in that the first and second noise-to-signal measuring devices comprise a slow response control circuit for maintaining the average value of the input signal from the adder at a reference value, and means for filtering this averaged value and detecting the power fluctuations remaining in the signal and generating a signal proportional to these fluctuations. Additionally, the first and second adjustable filters may be structured to have transfer functions across a predetermined bandwidth of W.sub.0 [1+W.sub.1 .omega.+W.sub.2 .omega..sup.2 ] or W.sub.0 [1+W.sub.1 .omega.+W.sub.2 .omega..sup.2 +W.sub.3 .omega..sup.3 ], where W.sub.0 , W.sub.1, W.sub.2 and W.sub.3 are signal weights and .omega. represents the frequency variation of the input signal from its carrier.
REFERENCES:
patent: 3735266 (1973-05-01), Amitay
patent: 3963990 (1976-06-01), DiFonzo
patent: 3986123 (1976-10-01), Tirro
patent: 4027105 (1977-05-01), Kannowade
patent: 4112370 (1978-09-01), Monsen
Cooper, C. P., "Methods of Adaptive Cancellation for Dual Polarization Satellite Systems," Marconi Review, vol. 39, No. 200, pp. 1-24, First Quarter 1976.
Kannowade, H., "An Automatic Control System for Compensating Cross-Polarization Coupling in Frequency Re-Use Communication Systems," IEEE Transactions on Communication, vol. COM-24, No. 9, pp. 986-999, Sep. 1976.
Baird Charles A.
Pelchat Guy M.
Gerasimow Alexander
Griffin Robert L.
Harris Corporation
LandOfFree
Adaptive interference reduction system for crosstalk cancellatio does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adaptive interference reduction system for crosstalk cancellatio, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adaptive interference reduction system for crosstalk cancellatio will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1711109