Portable radio device

• US 6,285,893 B1
• Filed: 02/04/1999
• Issued: 09/04/2001
• Est. Priority Date: 02/09/1998
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Keirinbou, Hisashi
• Primary Examiner(s): Hunter, Daniel
• Assistant Examiner(s): ZEWDU, MELESS NMN
• Application Number:
  US09/244,191
• Time in Patent Office: 943 Days
• Field of Search: 455/90, 455/127, 455/129, 455/269, 455/550, 455/575, 455/562, 455/100, 455/351, 455/277.1, 455/278.1, 340/225.44, 340/426, 340/328, 340/334
• US Class Current: 455/575.7
• CPC Class Codes: H01Q 1/242 specially adapted for hand-held use
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 25/005 providing two patterns of opposite direction; back to back antennas H01Q25/004 takes precedence
• CPC Class Codes: H01Q 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• CPC Class Codes: H04B 1/3838 Arrangements for reducing RF exposure to the user, e.g. by changing the shape of the transceiver while in use
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04B 7/0602 using antenna switching H04B7/0686 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/0802 using antenna selection H04B7/0868 takes precedence; antenna beam directivity switching H01Q3/24

Abstract

Two sensors 2, 3 are provided for detecting an interception object on respective different surfaces of device housing 1 of a portable radio device. Two antennas 4, 5 are provided in the state of having directivity in respective different directions in device housing 1. Also provided are switching unit 8 for selectively connect antenna 4 or 5 to transmit-receive unit 7 and control unit 6 for controlling the same. Detection signals of respective sensors 2, 3 are applied to control unit 6 in the state that device housing 1 is fitted to a human body, the fitting direction of device housing 1 is determined through the detection signals, and switching unit 8 is controlled such that one of antennas 4, 5 on the side not contact with the human body is selected.

Claims

1. A portable radio device comprising:

a radio communication unit for processing an information signal transmitted by radio waves;

a device housing for holding said radio device and removably fitted to a mobile body;

a plurality of antennas dispersedly disposed at positions away from one another in said device housing;

a plurality of sensors provided corresponding to said plurality of antennas respectively for detecting an object close to said device housing; and

a switching circuit for comparing detection results of said respective sensors and selectively switching one of said antennas to be connected to said radio communication unit wherein said switching circuit receives detection outputs from said plurality of sensors, determines the fitting surface of said device housing in contact with the mobile body, and selects one of said antennas corresponding to the fitting surface when said radio communication unit is started.

2. The portable radio device according to claim 1, wherein the mobile body is a human body and said device housing is fitted to a portion of the human body through a fitting tool.

3. The portable radio device according to claim 1, wherein said radio communication unit includes one of a transmit-receive section, transmission section, and a reception section.

4. The portable radio device according to claim 1, wherein said device housing is of one thick rectangular plate shape and both widest front surface and back surface are respectively formed as a fitting surface to be contact with the mobile body, and two antennas and two sensors are respectively disposed on each of the fitting surfaces.

5. The portable radio device according to claim 1, wherein said sensor includes a combination of any one or more of an optical sensor, a strain sensor, and a temperature sensor.

6. The portable radio device according to claim 1, wherein said switching circuit periodically receives the detection outputs from said plurality of sensors at certain time intervals, determines the fitting surface of said device housing in contact with the mobile body, and selects one of said antennas corresponding to the direction of the fitting surface.

7. The portable radio device according to claim 1, wherein said switching circuit receives the detection outputs from said plurality of sensors when an indication input is received, determines the fitting surface of said device housing in contact with the mobile body, and selects one of said antennas corresponding to the direction of the fitting surface.