Abstract An antenna comprises an electrically conductive helical member having a first end and a second opposite end, an elongate substrate supporting such helical member and comprised of electrically insulative material, a ground plane member disposed adjacent the helical member first end, and an impedance matching device adjacent the ground plane member. The impedance-matching device defines an inductive-capacitive circuit, inclusive of inductance constituted by a portion of the initial turn of the helical member and capacitance, one plate of which is constituted by a portion of the initial turn of the helical member. The ground plane member supports the impedance matching device for adjustable positioning circumferentially of the helical member, thereby to effect different inductances in such circuit, and for adjustable positioning radially of the helical member, thereby to effect different capacitances in the circuit.
A wideband helical antenna, comprising: (a) an electrically conductive helical member having a first end and a second opposite end; (b) an elongate substrate supporting such helical member and comprised of electrically insulative material; (c) ground plane means for disposition adjacent said helical member first end and defining a detent for receipt of a keeper; and (d) electrically conductive means disposed in spaced juxtaposition with said helical member adjacent said first end thereof and having a slot therein for receipt of said keeper, whereby said electrically conductive means may be variably positioned radially of said helical member.
Claim 2
Dependent Claim
97 words
A wideband helical antenna, comprising: (a) an electrically conductive helical member having a first end and a second opposite end; (b) an elongate substrate supporting such helical member and comprised of electrically insulative material; (c) ground plane means for disposition adjacent said helical member first end and defining a detent for receipt of a keeper; and (d) electrically conductive means disposed in spaced juxtaposition with said helical member adjacent said first end thereof and having a slot therein for receipt of said keeper, whereby said electrically conductive means may be variably positioned radially of said helical member.
Claim 3
Dependent Claim
36 words
The invention claimed in claim 1 wherein said ground plane means detent comprises a slot extending circumferentially of said helical member, whereby said electrically conductive means further may be variably positioned circumferentially of said helical member.
Claim 4
Dependent Claim
40 words
The invention claimed in claim 1 wherein said electrically conductive means comprises a body having a first portion extending axially with said helical member and a second portion extending radially of said helical member, said second portion defining said slot.