Signal distribution system cascadable agc device and method

Abstract

A cascadable AGC amplifier in a signal distribution system includes a low noise cascadable amplifier having a through path and a cascadable output. The cascadable amplifier is also configured to provide AGC over a predetermined input power range. The cascadable AGC amplifier can be configured to provide gain or attenuation. When the cascadable AGC amplifier is implemented in a signal distribution system, typically as part of a signal distribution device, an input signal can be gain controlled and supplied to multiple signal paths without distortion due to degradation of signal to noise ratio or distortion due to higher order amplifier products. The distributed signal is not significantly degraded by distortion regardless of the number of cascadable AGC amplifiers connected in series or the position of the cascadable AGC amplifier in the signal distribution system.

1 . An apparatus comprising:
 a) at least one variable gain amplifier having an output;   b) a first crosspoint switch having a plurality of first crosspoint switch inputs and a plurality of first crosspoint switch outputs, each of the first crosspoint switch inputs coupled to the output of a respective one of the variable gain amplifiers, the first crosspoint switch operable to switchably couple any of the plurality of first crosspoint switch inputs to any one or more of the plurality of first crosspoint switch outputs; and   c) at least one frequency translation device having an input coupled to a respective first crosspoint switch output.   
   
   
       2 . The apparatus of  claim 1 , wherein each of the plurality of variable gain amplifiers comprises:
 a) a signal input coupled to receive a respective one of a plurality of satellite signals;   b) a control input; and   c) an output coupled to one of the inputs of the crosspoint switch, wherein each of the variable gain amplifiers is operable, responsive to a control signal received at the control input, to apply gain or attenuation to signals applied to the signal input of the variable gain amplifier.   
   
   
       3 . The apparatus of  claim 2 , further comprising a respective plurality of detectors, each detector having an input coupled to the signal input of a respective one of the variable gain amplifiers and an output coupled to the control input of the respective variable gain amplifier, each detector generating a control signal to control the gain or attenuation level of the respective variable gain amplifier as a function of power detected by the detector. 
   
   
       4 . The apparatus of  claim 2 , further comprising a respective plurality of detectors, each detector having an input coupled to the output of a respective one of the variable gain amplifiers and an output coupled to the control input of the respective variable gain amplifier to control the gain or attenuation level of the variable gain amplifier as a function of the power detected. 
   
   
       5 . An apparatus comprising:
 a) at least one variable gain amplifier having a signal input;   b) a crosspoint switch having a plurality of N crosspoint switch inputs and a plurality of crosspoint switch outputs, each of the N crosspoint switch outputs coupled to the signal input of a respective one of the variable gain amplifiers, the crosspoint switch operable to switchably couple any of the plurality of N crosspoint switch inputs to any one or more of the plurality of crosspoint switch outputs; and   c) at least one frequency translation device having an input, each variable gain amplifier output coupled to an input to a respective one of the frequency translation devices.   
   
   
       6 . The apparatus of  claim 5 , further comprising a plurality of detectors, each detector having an input coupled to the input of a respective one of the variable gain amplifiers and an output coupled to the control input of the respective variable gain amplifier, each of the detectors operable to control the gain or attenuation level of the respective variable gain amplifier as a function of the power detected. 
   
   
       7 . The apparatus of  claim 5 , further comprising a plurality of detectors, each detector having an input coupled to the output of a respective one of the variable gain amplifiers and an output coupled to the control input of the respective variable gain amplifier, each of the detectors operable to control the gain or attenuation level of the respective variable gain amplifier as a function of the power detected. 
   
   
       8 . The apparatus of  claim 1 , wherein each one of the crosspoint switch outputs is configured to couple to a single output device. 
   
   
       9 . The apparatus of  claim 1 , wherein at least one of the crosspoint switch outputs is configured to couple to more than one output device. 
   
   
       10 . A method for distributing one or more channels included within each of N plurality of satellite signals over a network to one or more of output devices, the method comprising:
 a) inputting into a crosspoint switch each of the N satellite signals;   b) variably adjusting a power level of at least one crosspoint switch output signal; and   c) switching any channel included within the N satellite signals to one or more of a plurality of output devices via the crosspoint switch, wherein a single crosspoint switch is operable to selectively switch any channel included within the N satellite signals supplied to any one of the output devices.   
   
   
       11 . The method of  claim 10 , wherein variably adjusting a power level comprises attenuating the signals. 
   
   
       12 . The method of  claim 10 , wherein variably adjusting a power level comprises amplifying the signals.