Rockwell Collins, Inc.

Jeffrey D Schmidt

John Jorgenson

Joseph F Jiacinto

Timothy S Lappe

Steven R Brown

A system and method for selectable sampling of a received RF input spectrum copies the input signal into a set of equivalent input spectra, one for each of a set of parallel sampling paths. The sampled input spectra are converted to a common sampling rate (e.g., baseband I/Q stream) and demodulated into a digital signal for each current time window of a sequence of time windows based on the common rate and corresponding to the receiver output stream. For each current time window, evaluation blocks store the demodulated signals to memory and evaluate the signals for signal quality, distortion, and/or receiver sensitivity based on figures of merit (FOM) determined by the waveform. The highest quality demodulated signal is selected, retrieved from memory, and appended to the digital output stream, providing low distortion demodulated digital output based on the RF input signal in real time or near real time.

Receiver sampling architecture for increased dynamic range using waveform feedback

A two-stage high-power RF limiter circuit for an RF signal receiver incorporates a heavy limiting stage to limit high energy pulses of a received RF signal to a desired power threshold over a sustained time period, while a light limiting stage reacts quickly to high energy pulses to reduce spike leakage associated with the slower reaction time of the heavy limiting stage. Both heavy and light limiting stages incorporate PIN diodes biased to a voltage just below the desired power threshold (the light limiter biased to a slightly higher voltage than the heavy limiter) so the PIN diodes do not activate until power levels are high enough to warrant limiting. The holdoff voltage across the PIN diodes is maintained by Zener diodes biased to a voltage corresponding to the power threshold, allowing the PIN diodes to self-bias once the power threshold is reached.

Growing community of inventors

Marion, IA, United States of America

Jeffrey D Schmidt