Highly linear analog-to-digital conversion system and method thereof

A method to compensate for the intermodulations, comprising the steps of:

• (a) converting an output of an analog to digital converter to a base-band equivalent of a carrier-based signal;
• (b) upsampling the base-band data;
• (c) shifting the base-band of the upsampled signal;
• (d) equalizing the shifted signal;
• (e) shifting the equalized signal back to its original base-band;
• (f) linearly filtering the shifted signal of said step (e);
• and
• (g) downsampling the filtered signal.

A method for converting analog signals to digital signals having reduced non-linear distortions, comprising the steps of:

• (a) receiving an input analog signal;
• (b) converting the input analog signal to a digital signal;
• and
• (c) generating an equalized digital signal by adaptively reducing non-linear distortions in the digital signal;
• said step (c) including the substeps of,
• (c1) generating a plurality of functional streams, the functional streams comprising non-linear combinations of the digital signal,
• (c2) generating a filtered output, using a plurality of finite impulse response filters, of the corresponding functional stream, and
• (c3) summing the filtered outputs of the finite impulse response filters to output the equalized digital signal.

A method for producing an equalized digital output from an analog input, comprising:

• (a) converting an analog input into digital data, the digital data having a first domain, the first domain having a first number of dimensions;
• (b) converting the digital data into a second domain, the second domain having a second number of dimensions, the second number of dimensions being greater than the first number of dimensions;
• (c) linearly filtering the converted digital data;
• and
• (d) converting the linearly filtered digital data into the equalized digital signal having a domain having the first number of dimensions.

A communication system, comprising:

• a transmitter for transmitting an analog signal at saturation, the analog signal having non-linear distortions therein;
• a receiver for receiving the transmitted analog signal;
• an analog to digital converter circuit to convert the analog signal into a digital signal;
• and
• a non-linear equalizing circuit to remove non-linear distortions from the digital signal;
• said non-linear equalizing circuit including,
• a circuit to convert the digital signal having non-linear distortions therein into a plurality of monomial combinations of the digital signal having non-linear distortions therein to generate a plurality of systolic form digital signals without redundant terms, and
• a plurality of parallel linear finite impulse response filters such that each systolic form digital signal is filtered by a linear finite impulse response filter.

A communication system, comprising:

• a transmitter for transmitting an analog signal at saturation, the analog signal having non- linear distortions therein;
• a receiver for receiving the transmitted analog signal;
• an analog to digital converter circuit to convert the analog signal into a digital signal;
• and
• a non-linear equalizing circuit to remove non-linear distortions from the digital signal;
• said non-linear equalizing circuit including,
• a circuit to convert the digital signal having non-linear distortions therein into a plurality of parallel non-linear digital signals, and
• a plurality of parallel linear finite impulse response filters such that each parallel non-linear digital signal is filtered by a linear finite impulse response filter.

A communication system, comprising:

• a transmitter for transmitting an analog signal at saturation, the analog signal having non-linear distortions therein;
• a receiver for receiving the transmitted analog signal;
• an analog to digital converter circuit to convert the analog signal into a digital signal;
• and
• a non-linear equalizing circuit to remove non-linear distortions from the digital signal;
• said non-linear equalizing circuit including,
• a first circuit to convert the digital signal, having non-linear distortions and being of a first domain, into a second domain, the second domain having a number of dimensions, the number of dimensions being greater than the number of dimensions in the first domain,
• a filter to linearly filter the converted digital signal, and
• a second circuit to convert the linearly filtered digital signal into a equalized digital signal being of a domain having the first number of dimensions.

An analog receiver, comprising:

• an analog to digital converter circuit to convert a received analog signal into a digital signal;
• and
• a non-linear equalizing circuit to remove non-linear distortions from the digital signal;
• said non-linear equalizing circuit including,
• a circuit to convert the digital signal having non-linear distortions therein into a plurality of monomial combinations of the digital signal having non-linear distortions therein to generate a plurality of systolic form digital signals without redundant terms, and
• a plurality of parallel linear finite impulse response filters such that each systolic form digital signal is filtered by a linear finite impulse response filter.

An analog receiver, comprising:

• an analog to digital converter circuit to convert a received analog signal into a digital signal;
• and
• a non-linear equalizing circuit to remove non-linear distortions from the , digital signal;
• said non-linear equalizing circuit including,
• a circuit to convert the digital signal having non-linear distortions therein into a plurality of parallel non-linear digital signals, and
• a plurality of parallel linear finite impulse response filters such that each parallel non-linear digital signal is filtered by a linear finite impulse response filter.

An analog receiver, comprising:

• an analog to digital converter circuit to convert a received analog signal into a digital signal;
• and
• a non-linear equalizing circuit to remove non-linear distortions from the digital signal;
• said non-linear equalizing circuit including,
• a first circuit to convert the digital signal, having non-linear distortions and being of a first domain, into a second domain, the second domain having a number of dimensions, the number of dimensions being greater than the number of dimensions in the first domain,
• a filter to linearly filter the converted digital signal, and
• a second circuit to convert the linearly filtered digital signal into a equalized digital signal being of a domain having the first number of dimensions.

A digital equalizer for removing non-linear distortions, comprising:

• a first circuit to convert a digital signal, having non-linear distortions and being of a first domain, into a second domain, the second domain having a number of dimensions, the number of dimensions being greater than the number of dimensions in the first domain;
• a filter to linearly filter the converted digital signal;
• and
• a second circuit to convert the linearly filtered digital signal into a equalized digital signal being of a domain having the first number of dimensions.

A method for linearly filtering a digital signal, comprising:

• (a) bit-shifting a digital signal;
• (b) multiplying the bit-shifted digital signal by a predetermined coefficient;
• and
• (c) eliminating all overflow bits after the multiplication operation to produce a filtered digital signal.

A linear finite impulse response filter, comprising:

• a shift register to bit-shift a digital signal;
• a multiplier to multiply the bit-shifted digital signal by a predetermined coefficient;
• and
• an algebraic residual circuit to eliminate all overflow bits after the multiplication operation to produce a filtered digital signal.