Hughes Aircraft Company

Andrew A Walston

Gregory L Tangonan

Irwin L Newberg

Jar Jar Lee

Willie W Ng

Howard S Nussbaum

Richard C Lind

Michael Wechsberg

Huan W Yen

An apparatus and method for frequency translation of true time delay signals in a phased array radar system is provided. A local oscillator signal is true time delayed or modulo 2.pi. phase shifted and then mixed with a true time delay beamsteering signal from a true time delay circuit to produce a frequency translated transmit signal which is supplied to an antenna element. A receive signal received by an antenna element is mixed with a true time delayed or modulo 2.pi. phase shifted local oscillator signal to provide a frequency translated receive signal. The frequency translated receive signal can then be passed through a true time delay circuit and other subsequent processing circuitry. The frequency translation permits higher frequency transmit and receive signals to be used with lower frequency true time delay devices.

Frequency translation of true time delay signals

Optoelectronic switching apparatus employing optoelectronic switching devices interconnected by optical media having different delay lengths and an multiport optical coupler. The optoelectronic switching apparatus provides for a multibit true-time-delay beamsteerer for beamsteering phased array antennas. The present invention combines two types of optoelectronic devices, lasers and photodiode switches, using an interconnected passive optical network comprising the optical fibers and the optical coupler. The switches, and input and output signal networks coupled to the respective switches, are controlled using a control signal generator. Using this scheme, any input can be independently selected and a signal can be routed to any output. Furthermore, the product of the total number of different interconnect paths (N.times.M) is provided which provides a greater number of delay lengths than is provided by using only one type of switch (i.e. laser (N) or photodiode (M)) alone. The present invention also provides for improved insertion loss while increasing the number of delay paths.

Optoelectronic multibit beamsteering switching apparatus

Growing community of inventors

Los Angeles, CA, United States of America

Andrew A Walston