High performance sigma-delta-sigma low-pass/band-pass modulator based analog-to-digital and digital-to-analog converter

An apparatus, comprising:

• an array of at least one or more tunable band-pass filter stages in parallel groups, all stage outputs of said array being summed to a single group output and at least one or more parallel groups in cascade, a first parallel group receiving an input signal at all stage inputs, a last parallel group providing an output to an output processor;
• a first set of interstage group gain elements, one each being coupled between an output of each of said at least one or more tunable band-pass filter stages and an output summer of each group, respectively;
• a second set of gain elements, one each being coupled between the input of the apparatus and an input of each succeeding one of said at least one or more tunable band-pass filter stages in the cascaded group;
• an output processor for providing signal conversion at an output of the apparatus and for providing inverse conversion for one or more feedback outputs;
• and
• a feedback loop coupling the one or more feedback output signals to each of said at least one or more tunable band-pass filter stages wherein each of said at least one or more tunable band-pass filter stages is tunable to a respective predetermined frequency.

An apparatus, comprising:

• at least one or more means for providing a tunable band-pass filter function in cascade, a first one of a said at least one or more tunable band-pass filter function providing means receiving an input signal at an input of the apparatus, a last one of said at least one or more tunable band-pass filter function providing means providing a first output;
• a first set of means for providing an adjustable gain level, one of said first set of adjustable gain level providing means being coupled between each of said at least one or more tunable band-pass filter function providing means, respectively;
• a second set of means for providing an adjustable gain level, one of said second set of adjustable gain level providing means being coupled between an input of the first one of said at least one or more tunable band-pass filter function providing means and an input of a succeeding one of said at least one or more tunable band-pass filter function providing means, respectively;
• processing means, coupled between the first output and an output of the apparatus, for processing a signal for signal conversion, and for providing inverse conversion for one or more feedback outputs;
• and
• means for feeding back a signal, said feedback means coupling the one or more feedback outputs to each of said at least one or more tunable band-pass filter function providing means, respectively, wherein each of said at least one or more tunable band-pass filter function providing means is tunable to a respective predetermined frequency.