Real-time fault detection in an instrument landing system

摘要

An electronic system with real-time fault detection is provided. In one embodiment, the system includes analog circuitry, having a first input coupled to receive an input signal and a second input coupled to receive a test signal. The test signal is at an edge of a selected band that contains the input signal. The test signal is used to identify faults in the electronic system during operation of the electronic system. The electronic system further includes an analog to digital (A/D) converter coupled to an output of the analog circuitry. The A/D converter generates digitized spectrum. Digital circuitry is coupled to the output of the A/D converter. The digital circuitry processes the input signal from the band to provide an output for the system and processes the test signal to detect faults in the analog circuitry, the digital circuitry and the A/D converter.

主权项

1. A receiver for an instrument landing system with real-time fault detection, the receiver comprising:
a test signal generator; an antenna; a wideband front end, having an input coupled to the antenna and the test signal generator, wherein the test signal generator injects a test signal at an edge of a selected RF band that contains an expected guidance signal, the test signal used to identify faults in the instrument landing system; an analog to digital (A/D) converter coupled to an output of the wideband front end that generates digitized spectrum, the digitized spectrum including the injected test signal and the selected RF band, including the expected guidance signal; a bank of digital down-converters, coupled to the output of the A/D converter; a main processor selectively coupled to the bank of digital down-converters; a monitor processor selectively coupled to the bank of digital down-converters; wherein the bank of digital down-converters selectively provides the test signal and the expected guidance signal from the digitized spectrum to the main and monitor processors to provide lateral and vertical guidance to a flight control system and to detect faults in the analog and digital circuitry of the receiver.