Southwest Research Institute

US Government as Represented by the Secretary of the Army

United States of America as Represented by the Secretary of the Air Force

Douglas N Travers

William Matthew Sherrill

Jackie E Hipp

Terence C Green

Richard L Johnson

Paul E Martin

William G Guion

Willis L Donaldson

Martin J Prucha

A system using two magnetic quadrupole antennas, two magnetic dipole antennas and means for processing the respective antenna signal outputs provides unambiguous estimates of elevation and polarization for an incident RF signal. The system uses an efficient procedure to process the signals from a small aperture array of fixed loop elements for the purpose of providing radio direction of arrival information that is free of intrinsic polarization error. The directional information is developed by performing a simultaneous arctangent operation on signals output from the antennas or as the measured phase difference between a quadrature summed quadrupole output and a quadrature summed dipole output compensated by a phase offset between the dipole antennas and the quadrupole antennas.

Sky wave direction finder

A radio interferometer system and method for obtaining more accurate readings from a radio source by processing the received signal as a plane wave and establishing coincidence locations and conditions, and discarding readings which are noncoincidence within a selected tolerance.

Phase linear interferometer system and method

A sky wave DF antenna system is disclosed. It is able to respond to an incoming transmitted signal and define the direction of the transmitter. It utilizes six or more simple loops connected and arranged to form a spaced loop antenna system which indicates the incoming direction of the transmitted signal without regard to the polarization or the elevational angle of the sky wave.

Sky wave DF antenna system

Apparatus for terminating teletype signal lines and mixing cryptographic teletype signals to furnish an enciphered teletype signal including a secondary operating mode of the mixer unit to retransmit the incoming teletype signal in the event enciphering or deciphering is not required.

Teletype mixer apparatus for coding and decoding

A plurality of dipoles is arranged and connected to form a quadrupole Adcock Antenna system which is connected with direction finding circuitry to define a direction finder system of which two embodiments are disclosed. The system responds to any transmitter to be located.

Growing community of inventors

San Antonio, TX, United States of America

Douglas N Travers