Patent ID: 7233624
Filing Date: 2007-06-19
Classification: H03G,H03M

Abstract:
1. A gain controller for obtaining wide range and high resolution analog-to-digital conversion of an in-phase (I) signal and a quadrature (Q) signal, the gain controller comprising: (a) a first analog compressor for compressing the I signal into a compressed analog I signal; (b) a first analog-to digital (A/D) converter electrically coupled to an output of the first analog compressor for converting the compressed analog I signal into a compressed digital I signal; (c) a first expander electrically coupled to an output of the first A/D converter for expanding the compressed digital I signal back to an original linear scale; (d) a second analog compressor for compressing the Q signal into a compressed analog Q signal; (e) a second A/D converter electrically coupled to an output of the second analog compressor for converting the compressed analog Q signal into a compressed digital Q signal; (f) a second expander electrically coupled to an output of the second A/D converter for expanding the compressed digital Q signal back to an original linear scale; (g) a first low pass filter electrically coupled to an output of the first expander for filtering the output of the first expander to generate a filtered I signal; (h) a second low pass filter electrically coupled to an output of the second expander for filtering the output of the second expander to generate a filtered Q signal; and (i) a normalization circuit coupled to outputs of the first and second low pass filters for adjusting the gain of the filtered I and Q signals on a block-by-block basis as a function of averaged combined signal strength measurements of the filtered I and Q signals.