Arrangement for a mobile terminal

• US 6,580,397 B2
• Filed: 10/26/2001
• Issued: 06/17/2003
• Est. Priority Date: 10/27/2000
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Lindell, Bo
• Primary Examiner(s): Ho, Tan
• Application Number:
  US09/983,861
• Publication Number:
  US 20020053991A1
• Time in Patent Office: 599 Days
• Field of Search: 343/700.MS, 343/702, 343/846, 343/848, 343/850, 343/860, 455/89, 455/90
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence

Abstract

The invention relates to an antenna system for a mobile terminal (1), comprising a casing (2), which accommodates radio electronic circuits (REC) and a screening device (SD) for the radio electronic circuits. The antenna system comprises an end-fed antenna (4), having an extended shape and being connected to the radio electronic circuits (REC). The antenna system comprises a counterpoise element (5), located near one end of the end-fed antenna (4), and the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element (5) by the radio electronic circuits (REC).

Claims

1. An antenna system for a mobile terminal, comprising:

a casing, which accommodates radio electronic circuits and a screening device for the radio electronic circuits;

an end-fed antenna, having an extended shape and being connected to the radio electronic circuits; and

a counterpoise element, located near one end of the end-fed antenna,

wherein;

the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element by the radio electronic circuits, and

wherein the end-fed antenna is located within and extends through a major part of the casing.

2. An antenna system according to claim 1, wherein the electrical length of the end-fed antenna is approximately a multiple of a half wavelength.

3. An antenna system according to claim 2, wherein the electrical length of the end-fed antenna approximately corresponds to a full and a half wavelength of two respective frequencies, on which the end-fed antenna is intended to transmit or receive.

4. An antenna system according to claim 1, wherein the counterpoise element is smaller than the end-fed antenna, and located at a distance from the end-fed antenna.

5. An antenna system according to claim 4, wherein the distance is on the order of the size of the counterpoise element.

6. An antenna system according to claim 1, wherein the counterpoise element is small in relation to the wavelength of frequencies to be used in communications between the mobile terminal and a base station.

7. An antenna system according to claim 1, wherein the counterpose element is extended in a direction transverse to the longitudinal direction of the end-fed antenna.

8. An antenna system according to claim 1, wherein at least two impedance matching networks form a multi-port filter, adapted to allow simultaneous use of the antenna system for two or more frequency bands.

9. An antenna system according to claim 8, wherein the impedance matching networks are connected in parallel to the counterpoise element.

10. An antenna system according to claim 8, for a mobile terminal provided with a speaker, wherein the speaker forms a counterpoise element for the antenna system.

11. An antenna system for a mobile terminal, comprising:

a casing, which accommodates radio electronic circuits and a screening device for the radio electronic circuits;

an end-fed antenna, having an extended shape and being connected to the radio electronic circuits; and

a counterpoise element, located near one end of the end-fed antenna,

wherein;

the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element by the radio electronic circuits, and

wherein the end-fed antenna forms a chassis.

12. An antenna system for a mobile terminal, comprising:

a casing, which accommodates radio electronic circuits and a screening device for the radio electronic circuits;

an end-fed antenna, having an extended shape and being connected to the radio electronic circuits; and

a counterpoise element, located near one end of the end-fed antenna,

wherein;

the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element by the radio electronic circuits, and

wherein the screening device forms the end-fed antenna.

13. An antenna system for a mobile terminal, comprising:

a casing, which accommodates radio electronic circuits and a screening device for the radio electronic circuits;

an end-fed antenna, having an extended shape and being connected to the radio electronic circuits; and

a counterpoise element, located near one end of the end-fed antenna,

wherein;

the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element by the radio electronic circuits, and

wherein the end-fed antenna forms a chassis, and the screening device.

14. An antenna system for a mobile terminal, comprising:

a casing, which accommodates radio electronic circuits and a screening device for the radio electronic circuits;

an end-fed antenna, having an extended shape and being connected to the radio electronic circuits; and

a counterpoise element, located near one end of the end-fed antenna,

wherein;

the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element by the radio electronic circuits, and

wherein the end-fed antenna forms a casing, or a part thereof, for the mobile terminal.

15. An antenna system for a mobile terminal, comprising:

a casing, which accommodates radio electronic circuits and a screening device for the radio electronic circuits;

an end-fed antenna, having an extended shape and being connected to the radio electronic circuits; and

a counterpoise element, located near one end of the end-fed antenna,

wherein;

the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element by the radio electronic circuits, and

wherein the end-fed antenna forms a casing, or a part thereof, for the mobile terminal, and a chassis for the mobile terminal.

16. An antenna system for a mobile terminal, comprising:

a casing, which accommodates radio electronic circuits and a screening device for the radio electronic circuits;

an end-fed antenna, having an extended shape and being connected to the radio electronic circuits; and

a counterpoise element, located near one end of the end-fed antenna,

wherein;

the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element by the radio electronic circuits,

wherein at least two impedance matching networks form a multi-port filter, adapted to allow simultaneous use of the antenna system for two or more frequency bands, and

wherein the antenna arrangement is for a mobile terminal provided with a speaker, wherein the speaker forms a counterpoise element for the antenna.