Telecommunications – Receiver or analog modulated signal frequency converter – Noise or interference elimination
Reexamination Certificate
2007-06-19
2007-06-19
Nguyen, Duc M. (Department: 2618)
Telecommunications
Receiver or analog modulated signal frequency converter
Noise or interference elimination
C455S306000, C455S311000, C375S319000
Reexamination Certificate
active
10785783
ABSTRACT:
An amplification system for reducing DC offset in an input signal uses a low pass filter to isolate a DC component of the input signal. The system then subtracts the DC component from the input signal. In one embodiment, the system includes first and second amplifiers in addition to the low pass filter. The first amplifier amplifies the input signal to generate a first amplified signal at a differential output port of the amplification system. The second amplifier amplifies a low pass filtered version of the input signal to generate a second amplified signal at the differential output port of the amplification system. The outputs of the first and second amplifiers are connected to the differential output port of the amplification system in such a way that the first and second signals combine 180 degrees out of phase at the output port. An automatic gain control circuit is also provided that automatically adjusts the gain of the amplification system without changing a bias level associated with the first and second amplifiers.
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Intel Corporation
Nguyen Duc M.
Schwegman Lundberg Woessner & Kluth P.A.
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