James R Montgomery

US Patent:

60724374, Jun 6, 2000

Filed:

Jun 29, 1998

Appl. No.:

9/106833

Inventors:

Kurt A. Zimmerman - Atlanta GA
James M. Howell - Woodstock GA
James P. Montgomery - Roswell GA

Assignee:

EMS Technologies, Inc. - Norcross GA

International Classification:

H01Q 1906

US Classification:

343753

Abstract:

Varying the azimuth and elevation beam patterns for an antenna. For a horn-type antenna implemented by a parallel-plate waveguide structure, an input port can accept an electromagnetic signal and an output slot can transmit the electromagnetic signal. An azimuth lens can be placed proximate to the output slot for adjusting the antenna beam pattern within the azimuth plane. The azimuth lens comprises two or more lens elements, each typically having a cylindrical shape and comprising a dielectric material, which support the generation of discrete beams in the azimuth plane in response to the electromagnetic signal output by the output slot. These discrete beams can sum in-phase to form a composite beam having a shape or pattern generally defined by the characteristics of the azimuth lens elements. Specifically, this composite beam has a pattern within the azimuth plane defined by the size and shape of the azimuth lens elements and the spacing between these elements. In addition, the horn-antenna can include an elevation lens that can rotate within the internal parallel-plate structure of the horn-type antenna to vary the beam pattern within the elevation plane.

US Patent:

60285621, Feb 22, 2000

Filed:

Jul 31, 1997

Appl. No.:

8/903678

Inventors:

Michael G. Guler - Lilburn GA
James P. Montgomery - Roswell GA

Assignee:

EMS Technologies, Inc. - Norcross GA

International Classification:

H01Q 1310

US Classification:

343771

Abstract:

A waveguide-implemented antenna comprising a planar array of waveguide slot radiators for communicating electromagnetic signals exhibiting simultaneous dual polarization states. The antenna can consist of parallel waveguides of rectangular or ridged cross section. The broadwalls of each parallel waveguide contain a linear array of input slots for receiving (transmitting) electromagnetic signals having a first polarization state from (to) the parallel waveguide and for transmitting (receiving) those signals into (from) an array of cavity sections. The cavity sections comprise a short section of uniform waveguide with a length of much less than a wavelength in the propagation direction. The cavity sections feed to output slots which are rotated relative to the input slots; such that the output slots exhibit a second polarization state, which they radiate (receive) to (from) free space. By interlacing parallel waveguides with alternating +45 degree and -45 degree rotations of the output slots, two independent antennas are formed exhibiting simultaneous dual polarizations.

US Patent:

50756486, Dec 24, 1991

Filed:

Mar 30, 1989

Appl. No.:

7/330617

Inventors:

Roger G. Roberts - Auburn GA
Jeff M. Alexander - Clarkston GA
James P. Montgomery - Roswell GA

Assignee:

Electromagnetic Sciences, Inc. - Norcross GA

International Classification:

H01P 504
H01P 5107
H01P 512

US Classification:

333128

Abstract:

A miniaturized waveguide mode ferrite RF phase shifter is efficiently transitioned to a matched impedance microstrip transmission line mode at either end to result in an ultra small, efficient and lightweight essentially "planar" phase shifter device having wide application in the microwave industry.