Low-power c.w. Doppler navigation equipment

A low-power c.w. Doppler navigation aid is described which has been designed for use in maritime reconnaissance aircraft. Low-voltage klystrons combined with high-gain fixed aerials provide adequate system gain for operating over all surfaces except the calmest water. Display is in the form of drum counters showing distance flown along heading and distance drifted at right angles to heading, port or starboard. Accuracy of measuring these distances is within ±1% of the total distance flown.