US 6,147,651 A · Antenna system

Abstract

The present invention provides an antenna system, which is used for a mobile wireless device and can be accommodated in or withdrawn from a telephone set main unit, whereby element length is shortened and strength is increased while avoiding deterioration of characteristics when the antenna is accommodated in the telephone set main unit. The antenna (40) comprises a helical antenna (41) having a feeding unit (42) and a whip antenna (43) having a feeding unit (44). The whip antenna (43) passes through the helical antenna (41), and the helical antenna (41) and the whip antenna (43) are electrically insulated from each other. Because the whip antenna (43) is designed to pass through the helical antenna (41), an antenna system for mobile wireless communication can be provided, in which element length is shortened and strength is increased.

Claims10

Dependent claims

A nondirectional antenna system comprising:

an antenna element connected to a radio circuit having a first frequency band, and a first parasitic element;
said first parasitic element located at a distance from the antenna element that is less than the wavelength of frequencies within the first frequency band, the distance being sufficiently small to achieve non-directivity;
a real equivalent electrical length of said first parasitic element in said first frequency band is not 1/2 wavelength or its integral multiple and is terminated by a first terminating circuit comprising a reactance element that varies the electrical length of the parasitic element.

A non-directional antenna system comprising:

a helical antenna operated when an antenna is located in a radio circuit main unit, and a whip antenna to be operated when the antenna is withdrawn from the radio circuit main unit, said helical antenna and said whip antenna are electrically insulated from each other, and said whip antenna is designed to pass through said helical antenna;
wherein said helical antenna has a connecting unit to be connected to a radio circuit when the antenna is located in the radio circuit main unit containing said radio circuit, said whip antenna is arranged closely to said connecting unit and has a first connecting unit to be connected to a ground plane when the antenna is located in the radio circuit main unit and a second connecting unit to be connected to the radio circuit when the antenna is drawn out from the main unit, said first connecting unit being located directly below said connecting unit of said helical antenna;
and further wherein there is provided a parasitic element located at a distance from the whip antenna that is less than the wavelength of the frequency band applied, and said parasitic element has a connecting unit to be connected to a ground plane via a circuit network comprising a reactance element when said whip antenna is withdrawn from the wireless device main unit.

Dependencies are inferred from the claim text.

Antenna system

Life of this patent

Antenna system

Life of this patent

Abstract

Claims10