Omnidirectional doppler beacon system

摘要

1,088,384. Radio navigation. STANDARD TELEPHONES & CABLES Ltd. May 6, 1965 [May 6, 1964], No. 19117/65. Addition to 940,508. Heading H4D. In a modification of the Doppler-effect radio beacon described in Specification 940,508, the central aerial is energized with radio-frequency energy modulated by a sub-carrier signal, the sub-carrier signal being frequency-modulated by a reference signal synchronized with the actual or simulated movement of the diametrically-opposed pairs of aerials on a circle. This is stated to reduce site errors in mountainous country.