NICHOLAS J CAFARELLI
Broker in Springfield, MA
License number
Massachusetts 135181
Issued Date
Aug 1, 1988
Expiration Date
May 22, 1991
Type
Broker
Address
Address
Springfield, MA 01108
Professional information
Scanning Antenna Having Phase Center Diversity
US Patent:
4811022, Mar 7, 1989
Filed:
Oct 31, 1986
Appl. No.:
6/925166
Inventors:
Nicholas J. Cafarelli - Springfield MA
Glen D. Adams - Chantilly VA
Glen D. Adams - Chantilly VA
International Classification:
G01S 108
US Classification:
342407
Abstract:
The object of this invention is to reduce the adverse effects of reflected electromagnetic radiation on the measurement threshold of a scanning beam. It has particular application to the time reference scanning beam of the international microwave landing system (MLS). In the present MLS configuration, the reflection induced errors during the "TO" scan are additive to those of the "FRO" scan. This invention describes a method and apparatus for compensating errors by reversing the phase of the reflections during the "FRO" scan, by displacing the phase center of the transmitantenna during that scan. System performance is enhanced by the errors compensation.
Scanning Antenna Having Multipath Resistance
US Patent:
5134416, Jul 28, 1992
Filed:
Jan 8, 1990
Appl. No.:
7/461734
Inventors:
Nicholas J. Cafarelli - Springfield MA
Glen D. Adams - Chantilly VA
Glen D. Adams - Chantilly VA
International Classification:
H01Q 322, H01Q 324, H01Q 326
US Classification:
342372
Abstract:
The object of this invention is to reduce the adverse system performance effects resulting from antenna pattern sidelobes. It has particular application to the time reference scanning beam of the international microwave landing system (MLS) where sidelobe energy reflecting into the mainbeam at the receiver antenna introduces a timing measurement error. It also has application to systems such as height finding radar where signals entering through antenna pattern sidelobes degrade system performance. This invention describes methods and apparatus for system performance enhancement through the application of sidelobe amplitude and phase control.