US 6,191,752 B1 · HF antennas for wideband signals

Abstract

High frequency (HF) antennas for wideband signals are used in the tracking of railcars. These are rugged antennas especially adapted to the hostile environment of a railcar. One antenna is in the form of a magnetic loop. Another generates an electric field produced by a plate mounted just below the railcar undercarriage with an optional dielectric slab situated between the plate and the undercarriage. The antennas need not be specified in terms of optimal parameters since the approach taken is to provide a generic antenna structure adapted to being fitted underneath the carriage of a railcar. This generic structure exhibits a mitigated Q and is capable of broadband tuning. This feature makes the antenna easier and less costly to produce in large quantities and facilitates use of a standard fitting mechanism and installation procedure.

Claims10

Dependent claims

An HF (high frequency) antenna for mounting under a railcar adapted for traveling on rails, comprising:

a first loop formed by a solid conductor fitted toward one end of an undercarriage of the railcar, said first loop being mounted vertically so that a line perpendicular to a plane defined by said loop is horizontal and at right angles to the length of the railcar;
and
a second loop larger than the first loop and defined by the undercarriage of the railcar, wheel trucks of the railcar, a rail, and wheels of said wheel trucks in contact with said rail, the first loop being operable to excite the second loop.

Dependencies are inferred from the claim text.

HF antennas for wideband signals

Life of this patent

HF antennas for wideband signals

Life of this patent

Abstract

Claims10