David A Tulchinsky

US Patent:

20020181874, Dec 5, 2002

Filed:

May 29, 2002

Appl. No.:

10/156197

Inventors:

David Tulchinsky - Arlington VA, US
Paul Matthews - Ellicott City MD, US

International Classification:

G02B006/26
G02B006/28
G02B006/35

US Classification:

385/039000, 385/015000, 385/140000, 385/024000, 385/016000

Abstract:

An array antenna apparatus for producing a time-delay beamformed RF signal includes a laser, a modulator for RF modulating the laser optical signal, a first plurality of optical paths coupling the modulator output to a dispersive prism, another plurality of optical paths coupling the dispersive prism outputs to a corresponding plurality of time delay trimmers, an attenuator coupled to each time delay trimmer, and an optical switching matrix to which the time delay trimmers outputs are input. The inputs to the optical switching matrix accordingly are time and amplitude adjusted to remove front end errors prior to rerouting. This is repeated in the back end of the apparatus, in which the switching matrix outputs are each applied to a corresponding attenuator, the outputs of which are then each applied to a photodetector to generate a plurality of replica RF signals that are each applied to a time shifter, thereby producing an error-corrected output that is then applied to an antenna array. The output of the antenna array is a time-delay beamformed RF signal having a 2-D beamsteering capability.