Antenna diversity in wireless communication terminals

• US 5,905,467 A
• Filed: 07/25/1997
• Issued: 05/18/1999
• Est. Priority Date: 07/25/1997
• Status: Expired due to Term

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Narayanaswamy, Shankar, Rupp, Markus
• Primary Examiner(s): Kim, Robert H.
• Assistant Examiner(s): Lauchman, Layla G.
• Application Number:
  US08/900,247
• Time in Patent Office: 662 Days
• Field of Search: 343/702, 343/749, 343/725, 343/700 MS, 343/793, 455/89, 455/90, 455/575, 455/133, 455/134, 455/135
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/242 specially adapted for hand-held use
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/244 extendable from a housing along a given path
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H04B 7/0802 using antenna selection H04B7/0868 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/084 Equal gain combining, only phase adjustments antenna beam scanning or forming by phase or amplitude control H01Q3/26, e.g. phased arrays
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04B 7/0888 with selection

Abstract

A wireless communication terminal comprises a first housing section including an antenna for enabling wireless communications with the terminal and a second housing section including a second communications antenna, the second housing section being extendibly connected to the first housing in an manner such that when the second housing section is in its extended position the second antenna is located one half wavelength from the first antenna. One or both of the antennas may be a fixed type, e.g., a whip or stub, or a retractable type, e.g., telescoping. The antennas may be located external or may be internal (e.g., patch type antennas) to the housing sections.

Claims

1. A wireless communication terminal comprising

a first housing section including an antenna for enabling wireless communications with the terminal,

a second housing section of the terminal including a second communication antenna, the second housing section being extendibly connected to the first housing in an manner such that when the second housing section is in its extended position the second antenna is located at least one half wavelength from the first antenna, wherein the first and second antennae have matched impedances, at frequencies used for wireless communications, when the second antenna is in its extended position, and

an electronic signal combiner, responsive to characteristics of signals received over the first and second antennas, for determining how to combine these received signals.

2. The wireless communication terminal of claim 1 wherein the first and second antennae are the same type.

3. The wireless communication terminal of claim 1 wherein one of the first and second antennae is a retractable antenna.

4. The wireless communication terminal of claim 1 wherein one of the first and second antennae is a patch antenna.

6. The wireless communication terminal of claim 1 wherein the first and second antennae are located within their respective housing part.

7. The wireless communication terminal of claim 1 wherein the first antenna is fixed and the second antenna is extendible.

8. The wireless communication terminal of claim 1 wherein the first and second housing section are hinged together in a manner to form a foldable terminal.

9. The wireless communication terminal of claim 1 wherein the second housing section is slideably extendible from the first housing section.

14. The wireless communication terminal of claim 1 wherein at least one of the first and second antennas is a patch antenna which uses a microstrip feed to connect to a receive circuit of the terminal.

15. The wireless communication terminal of claim 1 wherein at least one of the first and second antennas is a patch antenna which uses a coaxial feed to connect to a receive circuit of the terminal.

16. The wireless communication terminal of claim 1 wherein at least one of the first and second antennas is a patch antenna which uses electromagnetic coupling to a receive circuit of the terminal.

17. The wireless communication terminal of claim 1 wherein at least one of the first and second antennas is a patch antenna which uses a slot feed to connect to a receive circuit of the terminal.

18. The wireless communication terminal of claim 1 wherein at least one of the first and second antennas is a patch antenna which uses a buried feed to connect to a receive circuit of the terminal.

5. A wireless communication terminal comprising

a first housing section including an antenna for enabling wireless communications with the terminal,

a second housing section of the terminal including a second communication antenna, the second housing section being extendibly connected to the first housing in an manner such that when the second housing section is in its extended position the second antenna is located at least one half wavelength from the first antenna wherein one of the first and second antennae is a stub antenna.

10. A wireless communication terminal comprising

a first housing section including an antenna for enabling wireless communications with the terminal,

a second housing section of the terminal including a second communication antenna, the second housing section being extendibly connected to the first housing in an manner such that when the second housing section is in its extended position the second antenna is located at least one half wavelength from the first antenna, wherein signals received from the first and second antennae are combined using a selective combining arrangement where the more powerful of the received first and second antenna signals is selected for use by the terminal.

11. A wireless communication terminal comprising

a first housing section including an antenna for enabling wireless communications with the terminal,

a second housing section of the terminal including a second communication antenna, the second housing section being extendibly connected to the first housing in an manner such that when the second housing section is in its extended position the second antenna is located at least one half wavelength from the first antenna, wherein signals received from the first and second antennae are combined using a switched combining arrangement whereby when the received signal on one antenna gets too weak, the terminal switches to the other antenna regardless of the signal level on the other antenna.

12. A wireless communication terminal comprising

a first housing section including an antenna for enabling wireless communications with the terminal,

a second housing section of the terminal including a second communication antenna, the second housing section being extendibly connected to the first housing in an manner such that when the second housing section is in its extended position the second antenna is located at least one half wavelength from the first antenna, wherein signals received from the first and second antennae are combined using a maximal-ratio combining arrangement in which the signals received from antennae are weighted according to their signal-to-noise ratio (SNR), co-phased and summed, and wherein the weighting factors are chosen to maximize the SNR of the summed signal.

13. A wireless communication terminal comprising

a first housing section including an antenna for enabling wireless communications with the terminal,

a second housing section of the terminal including a second communication antenna, the second housing section being extendibly connected to the first housing in an manner such that when the second housing section is in its extended position the second antenna is located at least one half wavelength from the first antenna, wherein signals received from the first and second antennae are combined using an equal-gain combining arrangement which adds together the received signals from both antennae.