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John Ladds Phones & Addresses

  • 19 Wendell St, Cambridge, MA 02138 (617) 547-2026
  • 19 Wendell St APT 3, Cambridge, MA 02138 (617) 547-2026
  • Stoneham, MA

Business Records

Name / Title
Company / Classification
Phones & Addresses
John Ladds
General Manager
Weed Man
Lawn Maintenance
201 Exeter Road,, Unit C, London, ON N6L 1A4
(519) 681-7555, (519) 681-9269
John Ladds
General Manager
Weed Man
Lawn Maintenance
(519) 681-7555, (519) 681-9269

Publications

Us Patents

Center-Fed Leaky Wave Antenna

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US Patent:
52314146, Jul 27, 1993
Filed:
Dec 23, 1991
Appl. No.:
7/813223
Inventors:
John P. Ladds - Cambridge MA
Assignee:
GTE Laboratories Incorporated - Waltham MA
International Classification:
H01Q 136
US Classification:
343895
Abstract:
An antenna has a dielectric slab with an inner surface and an outer surface. The inner surface is mounted on a metal backplate. A radiating spiral is located on the outer surface of the dielectric slab and has a pitch of one wavelength at the design frequency. A circular waveguide, for providing RF energy in the TM. sub. 01 mode, passes through the metal backplate to terminate at the inner surface of the dielectric slab. A metal cap is located on outer surface of the dielectric slab coaxial with the circular waveguide and at the center of the spiral. The metal cap has a surface is sloped away from the outer dielectric surface and has one or more concentric choke grooves formed on the sloped surface. The grooves are one quarter wavelength deep at the design frequency.
John P Ladds from Cambridge, MA, age ~95 Get Report