Improved Dynamic Range Analog-to-Digital Converter

An improved dynamic range analog-to-digital converter (ADC) subsystem is proposed that utilizes a passive superconducting microwave dispersive filter and a digital signal processor. The signal to be converted is passed through a superconducting passive filter and the output from the filter is used as the input to a low-temperature superconductor (LTS) ADC. The dispersive filter can be made using either a superconducting electromagnetic delay line or a microwave acoustic delay line with superconducting electrodes. The dispersive filter convolves its impulse response with the input signal to be converted. If the filter is implemented as a surface acoustic wave device it would not introduce any spurious intermodulation terms since it is a linear device. After the analog-to-digital conversion, the digital signal processor compresses the filter's dispersion back into an impulse. The effective gain in dynamic range is provided by the pulse compression gain of the dispersive filter.