Method and apparatus for forming array antenna beam of mobile terminal

• US 20050048921A1
• Filed: 09/02/2004
• Published: 03/03/2005
• Est. Priority Date: 09/03/2003
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Chung, Hee-Sok
• Granted Patent: US 7,457,587 B2
• Time in Patent Office: Days
• US Class Current: 455/63.400
• CPC Class Codes: H01Q 1/241 used in mobile communications, e.g. GSM H01Q1/247, H01Q1/248 take precedence
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence

Abstract

A method for forming an array antenna beam of a mobile terminal periodically compares transmit/receive characteristics of a three-dimensional adaptive beam with transmit/receive characteristics of an omnidirectional beam periodically. A beam direction having better transmit/receive characteristics is then selected. By horizontally rotating an array antenna beam toward up or down at an angle of 360° degrees, a direction having a maximum signal receiving value is searched, and a three-dimensional adaptive beam is set in the searched direction. By using position information of a mobile terminal together with the detected information, a beam direction is set. And, by comparing beam direction information set toward a maximum signal receiving direction with beam direction information set on the basis of position information of a base station/mobile terminal, an optimum beam is selected and formed, thereby improving transmit/receive characteristics of the mobile terminal.

Claims

1. A method for forming an array antenna beam of a mobile terminal, comprising:

comparing direction information of a first beam set toward a maximum signal receiving direction with direction information of a second beam set using position information of a base station and a mobile terminal; and

selecting one of the first and second beam direction information based on a predetermined variation degree of the first beam direction information when the first beam direction information and the second beam direction information are different.

2. The method of claim 1, wherein the selecting comprises:

checking a variation degree of direction information of the first beam;

selecting direction information of the second beam when the checked variation degree is above the predetermined variation degree; and

selecting direction information of the first beam when the variation degree is below the predetermined variation degree.

3. The method of claim 2, wherein the variation degree of direction information of the first beam is checked based on a list of direction information of the first beam set for a certain time.

4. The method of claim 1, further comprising:

randomly selecting one of the first and second direction information when the first beam direction information and the second beam direction information are the same.

5. The method of claim 1, wherein direction information of the first beam indicates direction information of a beam having better transmit/receive characteristics between transmit/receive characteristics of a three-dimensional adaptive beam and transmit/receive characteristics of an omnidirectional beam.

6. The method of claim 5, wherein the three-dimensional adaptive beam stetting comprises:

setting a beam in a first direction using a first antenna among a plurality of array antennas, and checking and storing first transmit/receive characteristics;

setting a beam in a second direction using a second antenna among the array antennas, and checking and storing second transmit/receive characteristics;

setting an array antenna beam toward a direction having a greater transmit/receive characteristics value between the first and second transmit/receive characteristics; and

searching a direction having a maximum transmit/receive characteristics value by rotating an array antenna beam in the set direction within a predetermined range of angles.

7. The method of claim 6, wherein the array antenna beam in the set direction is horizontally rotated with an angular range of 360°

.

8. The method of claim 6, wherein the first direction is a ‘

up’

direction and the second direction is a ‘

down’

direction.

9. The method of claim 6, wherein the array antenna includes a certain number of half-wavelength di-pole antennas.

10. The method of claim 6, wherein the first antenna is positioned at an upper portion of the mobile terminal, the second array antenna is positioned at a lower portion of the mobile terminal, and third, fourth and fifth antennas are positioned at central portions of the mobile terminal.

11. The method of claim 10, wherein the third, fourth and fifth antennas are disposed at equal intervals

12. The method of claim 10, wherein setting the array antenna beam comprises:

setting the array antenna beam by adjusting phases of each signal of the first, third, fourth and fifth antennas, if the first transmit/receive characteristics are greater than the second transmit/receive characteristics; and

setting the array antenna beam by adjusting phases of each signal of the second, third, fourth and fifth antennas, if the first transmit/receive characteristics are not greater than the second transmit/receive characteristics.

13. The method of claim 6, wherein the array antenna includes a certain number of wavelength/4 monopole antennas.

14. The method of claim 6, wherein the second antenna is positioned at a first portion of the mobile terminal, third to sixth antennas are positioned at a second portion of the mobile terminal, and the first antenna is positioned at a third portion of the mobile terminal which includes the third to sixth antennas.

15. The method of claim 14, wherein the first portion is a lower portion of the mobile terminal, the second portion is an upper portion of the mobile terminal, and the third portion is a center of a square face of the mobile terminal.

16. The method of claim 14, wherein setting the array antenna beam comprises:

setting the array antenna beam by adjusting phases of each signal of the first, third, fourth, fifth and sixth antennas, if the first transmit/receive characteristics are greater than the second transmit/receive characteristics; and

setting the array antenna beam by adjusting phases of each signal of the second, third, fourth, fifth and sixth antennas, if the first transmit/receive characteristics are not greater than the second transmit/receive characteristics.

17. The method of claim 1, wherein the position information of the base station is periodically broadcast through a forward channel.

18. The method of claim 1, wherein the position information of the mobile terminal is calculated by the mobile terminal including a GPS (Global Positioning System) unit.

19. The method of claim 1, wherein the position information of the mobile terminal is calculated by the mobile terminal using base station position information received from at least one base station.

20. An apparatus for forming an array antenna beam of a mobile terminal, comprising:

an array antenna;

a modem for setting a beam pattern toward a maximum three-dimensional signal receiving direction, setting a beam pattern based on position information of a base station and a mobile terminal, and selecting a beam pattern by comparing beam direction information set based on the position information with beam direction information set in the maximum signal receiving direction;

an array antenna beam controller/switch which forms a beam pattern set;

in the modem by adjusting phase of the array antenna; and

a RF unit for processing a RF (radio frequency) signal received through the array antenna beam controller/switch.

21. The apparatus of claim 20, wherein beam direction information set in the maximum signal receiving direction indicates direction information of a beam having better transmit/receive characteristics between transmit/receive characteristics of a three-dimensional adaptive beam and transmit/receive characteristics of an omnidirectional beam.

22. The apparatus of claim 21, wherein the three-dimensional adaptive beam is an adaptive beam for searching a direction having a maximum transmit/receive characteristics value by horizontally rotating an array antenna beam toward “

up”

or “

down”

at an angle of 360 degrees.

23. The apparatus of claim 20, wherein the first antenna is positioned at a first portion of the mobile terminal, the second antenna at a second portion, and the third to fifth antennas are positioned at a third portion of the mobile terminal, maintaining same intervals.

24. The apparatus of claim 23, wherein the first portion is an upper portion, the second portion is a lower portion, and the third portion is a center portion of the mobile terminal.

25. The apparatus of claim 20, wherein the second antenna is positioned at a first portion of the mobile terminal, the third to sixth antennas at an second portion, and the first antenna at a third portion made up of the third to sixth antennas.

26. The apparatus of claim 25, wherein the first portion is a lower portion, the second portion is an upper portion, and the third portion is a center of a square face of the mobile terminal.