The LRA-900 includes enhancements to a digitally controlled variable bandwidth filter which provides improved noise rejection and leading-edge tracking. Digital technology and proven frequency modulated continuous wave techniques are some of the enhancements.

Dual microprocessors perform automatic calibration that continuously compares the received ground return signal frequency with the frequency produced by separate, precise delay lines in each channel. This results in fine resolution, providing extremely high accuracy (+/- 1 ft) to best support autoland flare and touchdown computations. Resolution at touchdown is better than 1.2 inches.

Low component count and low stress level circuits give the LRA-900 incredible reliability. The LRA-900 makes on-board fault isolation quick, easy and effective. It also stores fault information for shop evaluation. A comprehensive self-test monitor in the system is capable of determining operational status to a 99% confidence level.

Ramp testing to simulate aircraft final approach is provided for aircraft system tests.

The entire receiver section, mixer, IF amplifier and signal presence detection circuits are continuously monitored, providing protection against failure modes that could generate erroneous altitude measurements.