Patent ID: 9000967
Filing Date: 2015-04-07
Classification: H03M

Abstract:
1. An apparatus for converting a continuous-time, continuously variable signal into a sampled and quantized signal, comprising: an input line for accepting an input signal that is continuous in time and continuously variable; a plurality of processing branches coupled to the input line, each of said processing branches including: (a) a sampling/quantization circuit, and (b) a digital bandpass interpolation filter having an input coupled to an output of the sampling/quantization circuit; and an adder coupled to outputs of the plurality of processing branches, wherein the digital bandpass interpolation filters in different ones of the plurality of processing branches have frequency responses that are centered at different frequencies, wherein the digital bandpass interpolation filter in at least one of said processing branches comprises: (i) a quadrature downconverter, (ii) a first lowpass filter and a second lowpass filter, (iii) a first interpolator and a second interpolator, each having an input for inputting a variable interpolant value, and (iv) a quadrature upconverter, and wherein input samples and output samples of said digital bandpass interpolation filter in at least one of said processing branches are different discrete-time representations of an underlying continuous-time signal, with the output samples representing an altered sampling period, as compared to the input samples, and with the sampling period being altered by an amount that depends on the variable interpolant value.