Antenna equipment

Claim 2

The antenna equipment of claim 1, wherein said notch is defined by a plane containing the center axis of said metal cylinder and a plane perpendicular to said center axis.

Claim 3

The antenna equipment of claim 1 or 2, wherein said inner conductor has a large-diameter portion at the side where it is connected to said feeder.

Claim 4

An antenna equipment comprising: a first rod antenna element; a metal cylinder provided at one end of said first antenna element and axially aligned therewith; an inner conductor connected to one end of said first antenna element and extended substantially along the center axis of said metal cylinder to form a coaxial line in combination therewith; a feeder having its core conductor connected to said inner conductor and its outer conductor connected to said metal cylinder at one side thereof opposite from said first antenna element; and a second coil antenna element disposed around a part of said first antenna element coaxially therewith and capacitively coupled to said first antenna element; wherein said coaxial line forms a coaxial impedance converter.

Claim 5

An antenna equipment comprising: a metal cylinder; an inner conductor extended in said metal cylinder along its center axis to form a coaxial line in combination with said metal cylinder; a first rod antenna element projecting out from said metal cylinder and retractable thereinto along its center axis; sliding contact means for causing one end of said inner conductor and said first antenna element to make sliding contact with each other; a feeder having its core conductor connected to said inner conductor and its outer conductor connected to said metal cylinder at one end thereof opposite from said first antenna element; and a second antenna element which is connected to said first antenna element when said first antenna element is retracted in said metal cylinder; wherein when said first antenna element is retracted in said metal cylinder, the inner end of said first antenna element makes contact with said core of said feeder and when said first antenna element is extended out from said metal cylinder, said second antenna element is disconnected from said first antenna element; and wherein said metal cylinder and said inner conductor constitute a coaxial impedance converter which matches the impedances of said first antenna element and said feeder and interconnects them.

Claim 6

The antenna equipment of claim 5, wherein said second antenna element is a coil antenna element disposed at the top of said metal cylinder in a manner to surround a part of said first antenna element, said first antenna element has near its top end a contact terminal extending therefrom at right angles to its axial direction, and said contact terminal makes contact with said coil antenna element when said first antenna element is retracted in said metal cylinder.

Claim 7

The antenna equipment of claim 6, wherein said coil antenna element has an intermediate tap which makes contact with said contact terminal when said first antenna element is retracted in said metal cylinder.

Claim 8

The antenna equipment of claim 7, wherein one end of said first antenna element is connected via a capacitor to said sliding contact means.

Claim 9

The antenna equipment of claim 5, wherein said inner conductor has a tubular large-diameter portion for the portion connected to said feeder and said first antenna element retracted in said metal cylinder is inserted into said tubular large-diameter portion of said inner conductor.

Claim 10

The antenna equipment of claim 5, wherein said second antenna element is a coil antenna element disposed at the top end of said first antenna element but electrically isolated therefrom.

Claim 11

The antenna equipment of claim 5, wherein said second antenna element is an inverted F antenna element disposed near the top end of said metal cylinder.

Claim 12

The antenna equipment of claim 5, wherein said first antenna element comprises first and second rods one of which is retractable into the other, said first antenna element has a length about one-half the wavelength used when extended and the length of said metal cylinder is about a quarter of said wavelength used.

Claim 13

An antenna equipment comprising: a metal cylinder; an inner conductor extended in said metal cylinder along its center axis and forming a coaxial line in combination with said metal cylinder; a first rod antenna element projecting out from said metal cylinder and retractable thereinto along its center axis; sliding contact means for bringing one end of said inner conductor and said first antenna element into sliding contact with each other; a feeder having its core conductor connected to said inner conductor and its outer conductor connected to said metal cylinder at one end thereof opposite from said first antenna element; and a second coil antenna element connected at one end to the tip of said first antenna element, said second antenna element projecting out from the top end from said metal cylinder when said first antenna element is retracted in said metal cylinder; wherein when said first antenna element is retracted in said metal cylinder, the inner end of said first antenna element makes contact with said core conductor of said feeder and when said first antenna element is extended out from said metal cylinder, said metal cylinder and said inner conductor constitute a coaxial impedance converter which matches the impedances of said first antenna element and said feeder and interconnects them.

Claim 14

The antenna equipment of claim 13, wherein said first antenna element has a length substantially equal to a quarter of the wavelength used and said second antenna element has a resonance point at said wavelength used.

Claim 15

The antenna equipment of claim 5 or 13, wherein an insulating guide tube for guiding and retracting thereinto said first antenna element is provided in said metal cylinder, with their center axes held in alignment with each other, said inner conductor is extended over the outer peripheral surface of said insulating guide tube in its axial direction and said sliding contact means is a metal piece which is connected to one end of said inner conductor and makes sliding contact with said first antenna element.

Claim 16

The antenna equipment of claim 15, wherein said metal piece forming said sliding contact means is an annular member and said first antenna element is inserted thereinto for sliding contact therewith.

Claim 17

The antenna equipment of claim 5 or 13, wherein said first antenna element is a tubular element, said inner conductor is an elastic wire disposed along the center axis of said metal cylinder and having its top end portion inserted in said tubular first antenna element, for guiding said first antenna element when it is retracted into said metal cylinder, the tip end portion of said elastic wire forming said sliding contact means which making sliding contact with said first antenna element in its tubular body.

Claim 18

The antenna equipment of claim 4, 5, or 13, wherein said metal cylinder has a slit formed therein in its axial direction to form a slot antenna and a core conductor and an outer conductor of another feeder are connected to opposed marginal edges of said metal cylinder across said slit.

Claim 19

The antenna equipment of claim 18, wherein a capacitor for frequency adjusting use is connected between said opposed marginal edges of said metal cylinder across said slit.

Claim 20

An antenna equipment comprising: a rod antenna element; a metal cylinder provided at one of said rod antenna element, with their center axes aligned with each other; an inner conductor connected to one end of said rod antenna element and extended substantially along the center axis of said metal cylinder to form a coaxial line in combination therewith; a first feeder having its core conductor connected to said inner conductor and its outer conductor connected to said metal cylinder at one end thereof opposite from said rod antenna element; a slot antenna formed by a slit formed in said metal cylinder in its axial direction; and a second feeder connected at one end to said slot antenna; wherein said coaxial line forms a coaxial impedance converter which matches the impedances of said antenna element and said first feeder and interconnects them.

Claim 21

The antenna equipment of claim 20, wherein a coil antenna element is disposed around a part of said rod antenna element coaxially therewith near the top end portion of said metal cylinder, said coil antenna element being capacitively coupled to said rod antenna element.

Claim 22

The antenna equipment of claim 20, wherein said rod antenna element is slidably received in said metal cylinder, and which further comprises: a coil antenna element disposed around a part of said rod antenna coaxially therewith near the top end portion of said metal cylinder, said coil antenna element being electrically isolated from said rod antenna and said metal cylinder; sliding contact means connected to the tip of said inner conductor and making sliding contact with said rod antenna element; and a contact terminal extending from the tip of said rod antenna element at right angles to its axis and making contact with one end of said coil antenna element when said rod antenna element is retracted in said metal cylinder; wherein when said rod antenna element is retracted in said metal cylinder, the lower end of said rod antenna element is connected to said core conductor of said feeder.

Claim 23

The antenna equipment of claim 2, wherein an insulating guide tube disposed in said metal cylinder substantially along its center axis, for guiding said rod antenna element inserted thereinto, and wherein said inner conductor is extended over the outer peripheral surface of said tubular insulating guide tube in its axial direction.

Claim 24

The antenna equipment of claim 23, wherein said sliding contact means is an annular metal member which holds said rod antenna element inserted thereinto.

Claim 25

The antenna equipment of claim 20, wherein: said rod antenna element is slidably received in said metal cylinder in its axial direction; said rod antenna element has at its tip a short-circuit portion which contacts said metal cylinder when said rod antenna element is retracted in said metal cylinder; the other end of said second feeder is connected in parallel to said first feeder; and the length of said second feeder is selected such that the impedance at the side of said second feeder, viewed from the connection point of said first and second feeders, is appreciably high when said rod antenna element is extended out from said metal cylinder and low when said rod antenna element is retracted in said metal cylinder.

Claim 26

The antenna equipment of claim 20, wherein said metal cylinder has a second slit formed therein in its axial direction to form a parasitic slot antenna.

Claim 27

The antenna equipment of claim 20, 22 or 25, wherein that portion of said inner conductor near said feeder is larger in diameter than that portion of said inner conductor near said rod antenna element.

Claim 28

The antenna equipment of claim 20, wherein a strip of metal is disposed on the outer peripheral surface of said metal cylinder with a dielectric spacer sandwiched therebetween, said strip of metal extending adjacent but in parallel to said slit.

Claim 29

The antenna element of claim 20, 22, or 25, wherein the length of said rod antenna element is about one-half the operating wavelength and the length of said metal cylinder in its axial direction is about a quarter of said operating wavelength used.

Claim 30

The antenna equipment of claim 20, 22, or 25, wherein a capacitor is connected in parallel to the connection point of said first feeder and said coaxial line.

Claim 31

The antenna equipment of claim 22, wherein said rod antenna element is a tubular element and said inner conductor is an elastic wire disposed along the center axis of said metal cylinder and having its tip inserted in the tubular body of said rod antenna element, said elastic wire sliding in said tubular body of said rod antenna element to guide it when said rod antenna element is retracted in said metal cylinder and said tip of said elastic wire forming said sliding contact means which makes sliding contact with said rod antenna element in its tubular body.