Communications: directive radio wave systems and devices (e.g. – With particular circuit – With recording
Patent
1998-08-28
2000-04-25
Sotomayor, John B.
Communications: directive radio wave systems and devices (e.g.,
With particular circuit
With recording
342192, 342 25, G01S 1389
Patent
active
060549475
ABSTRACT:
A radar system for a helicopter having a mast and a plurality of blades coupled to the mast by shaft portions of the blades includes a transmitter and a receiver respectively transmitting and receiving a pulsed radar beam through a feed horn, a generator for generating the radar beam energy for transmission by the transmitter, a processor, a display, and a passive reflectarray deposited on the underside of at least one blade of the helicopter. The reflectarray is a preferably flat array of passive microstrip elements which can impart a phase to the radar beam. A typical microstrip element is a patch whose dimensions may be controlled, and the size of which determines the phase for the location within the array of that element. The reflectarray is provided with a pattern which is designed to scatter the radar beam in a desired shape and direction to produce uniform mapping of the terrain over which the helicopter travels. According to another embodiment, a passive reflectarray is provided to the underside of at least one blade, while another passive reflect is provided to the topside of at least one blade, thereby permit both terrain and sky mapping. The radar system of the invention provides a radar system utilizing a lightweight and inexpensive passive radar reflector for use on helicopters of all sizes, and achieves 360.degree. coverage.
REFERENCES:
patent: 3896446 (1975-07-01), Kondoh et al.
patent: 4233605 (1980-11-01), Coleman
patent: 4638315 (1987-01-01), Raven
patent: 4737788 (1988-04-01), Kennedy
patent: 5614907 (1997-03-01), Kreitmair-Steck et al.
Pozar et al., "Design of Millimeter Wave Microstrip Reflectarrays", IEEE Transactions on Antennas and Propagation, vol. 45,No. 2, pp. 287-295, Feb. 1997.
Mittra et al., "Techniques for Analyzing Frequency Selective Surfaces-A Review",Proceedings of the IEEE, vol. 76, No. 12, pp 1593-1614, Dec. 1988.
Pozar et al., "Analysis of a Reflectarray Antenna Using Microstrip Patches of Variable Size", in Electronic Letters, Apr. 15, 1993, vol. 29, No. 8,pp 657-8.
Malibu Research, "Flaps.TM., Reflector Antennas", pp 1-6, Calabasas, CA.
Klausing, H. et al, "Feasability of a synthetic aperture radar with rotating antennas (ROSAR)", Int'l Radar Conference, pp. 51-56, 1990.
Gallagher Thomas A.
Gordon David P.
Jacobson David S.
Sotomayor John B.
LandOfFree
Helicopter rotorblade radar system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Helicopter rotorblade radar system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Helicopter rotorblade radar system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-996923