Multi-channel receiver with improved AGC
First Claim
1. A receiver comprising:
- a gain section adapted to generate, based on a gain control signal, an output signal from one or more received signals of a plurality of possible received signals;
a power detector adapted to generate an intensity value in response to the output signal;
a demodulator, for each possible received signal, adapted to characterize each of the possible received signals; and
a controller adapted to;
(1) select a setpoint value from a plurality of setpoint values in response to the characterizations of the plurality of demodulators, wherein each of the plurality setpoint values corresponds to a different one of a plurality of possible combinations of the plurality of possible received signals, wherein the plurality of possible combinations includes at least one combination having two or more of the possible received signals; and
(2) adaptively update the gain control signal based on changes in the intensity value to result in the intensity value approximating the setpoint value.
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Accused Products
Abstract
An improved multi-channel receiver for satellite broadcast applications or the like. In an exemplary embodiment, an AGC loop, under the control of an AGC processor, controls the gain of an analog sub-receiver adapted to simultaneously receive multiple signals to achieve a desired AGC setpoint signal intensity from the sub-receiver. Multiple digital demodulators, coupled to the sub-receiver by an analog-to-digital converter (ADC), demodulate the multiple received signals. The AGC controller, based upon which of the received signals are being demodulated, selects the desired AGC setpoint from a table of setpoints. The AGC controller may also provide selective power control to circuitry in the receiver and select the resolution of the ADC. The controller updates the AGC loop with step values selected from a group of values by an AGC control algorithm. Different groups of step values may be used by the controller depending on whether the signals are fading or not.
107 Citations
25 Claims
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1. A receiver comprising:
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a gain section adapted to generate, based on a gain control signal, an output signal from one or more received signals of a plurality of possible received signals; a power detector adapted to generate an intensity value in response to the output signal; a demodulator, for each possible received signal, adapted to characterize each of the possible received signals; and a controller adapted to; (1) select a setpoint value from a plurality of setpoint values in response to the characterizations of the plurality of demodulators, wherein each of the plurality setpoint values corresponds to a different one of a plurality of possible combinations of the plurality of possible received signals, wherein the plurality of possible combinations includes at least one combination having two or more of the possible received signals; and (2) adaptively update the gain control signal based on changes in the intensity value to result in the intensity value approximating the setpoint value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A receiver comprising:
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a gain section adapted to generate, based on a gain control signal, an output signal from one or more received signals of a plurality of possible received signals; a power detector adapted to generate an intensity value in response to the output signal; a demodulator, for each possible received signal, adapted to (i) determine whether or not to demodulate the output signal, (ii) generate a flag in accordance with the determination, and (iii) generate a signal strength signal for the possible received signal; and a controller adapted to (1) select a plurality of step sizes from a larger plurality of step sizes in response to the plurality of flags and the plurality of signal strength signals, (2) select a step size from the selected plurality of step sizes, and (3) adaptively update the gain control signal based on change in the intensity value and the selected step size. - View Dependent Claims (13, 14, 15, 16, 17, 18)
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19. A receiver comprising:
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a gain section adapted to generate, based on a gain control signal, an output signal from one or more received signals of a plurality of possible received signals; a power detector adapted to generate an intensity value in response to the output signal; a demodulator, for each possible received signal, adapted to determine whether or not to demodulate the output signal; and a controller adapted to (1) generate a setpoint value in response to the determinations of the plurality of demodulators and (2) adaptively update the gain control signal based on changes in the intensity value to result in the intensity value approximating the setpoint value, wherein; each demodulator is adapted to generate a flag indicating whether the corresponding possible received signal is or is not present in a form sufficient for demodulation; and the controller is adapted to select the setpoint value from a plurality of setpoint values in response to the plurality of flags in combination. - View Dependent Claims (20, 21, 22, 23, 24, 25)
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Specification