Compact cellular phone

• US 7,031,744 B2
• Filed: 12/03/2001
• Issued: 04/18/2006
• Est. Priority Date: 12/01/2000
• Status: Expired due to Fees

• Current Assignee: Coltera LLC
• Original Assignee: NEC Corporation
• Inventors: Hankui, Eiji, Kuriyama, Toshihide
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): Pham, Tuan
• Application Number:
  US09/998,242
• Publication Number:
  US 20020068602A1
• Time in Patent Office: 1,597 Days
• Field of Search: 455/550, 455/575.1, 455/575.3, 455/575.5, 455/575.7, 343/702, 343/700, 343/725, 343/742
• US Class Current: 455/550.1
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/245 with means for shaping the antenna pattern, e.g. in order to protect user against rf exposure
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence
• CPC Class Codes: H04B 7/0608 Antenna selection according to transmission parameters
• CPC Class Codes: H04B 7/0805 with single receiver and antenna switching H04B7/0822 takes precedence

Abstract

A compact cellular phone with a foldable configuration and two planar antennas having outward directivities are provided inside the compact cellular phone in the foldable configuration. An interval between the two planar antennas provided to a pair of housings is equal to or wider than a width of a human palm in a state in which the compact cellular phone is open. The two planar antennas are planar inverse F-type antennas or patch antennas and impedance around each of the two planar antennas is measured. Then, one of the two planar antennas, which has a preferred transmission characteristic, is selected and used.

Claims

1. A cellular phone including first and second housings, forming a pair of housings, folded upon each other when the cellular phone is closed, said cellular phone comprising:

two planar antennas disposed within said pair of housings, respectively, so that a surface having the greatest directivity of each of said two planar antennas is directed outward when said cellular phone is closed,

wherein when said cellular phone is used while being closed in a waiting state, both of said two planar antennas or either one of said two planar antennas is used to send or receive, and when said compact cellular phone is used while being open in a communication state, one of said two planar antennas, which has the better transmission state, is selected to send and receive, and

wherein by detecting and evaluating an impedance change and a physical quantity of a reflective wave caused by said impedance change on an electric-power transmission path provided inside said cellular phone, one of said two planar antennas, which has preferred transmission characteristics, is determined, selected, and used.

2. The cellular phone according to claim 1, wherein an interval between said two planar antennas disposed within said pair of housings is equal to or wider than a width of a human palm when said cellular phone is open.

3. The cellular phone according to claim 2, wherein said two planar antennas are disposed at an outermost position inside said pair of housings, respectively, when said cellular phone is closed.

4. The cellular phone according to claim 2, wherein said two planar antennas are two planar inverse F-type antennas or two patch antennas.

5. The cellular phone according to claim 1, wherein said two planar antennas are disposed at an outermost position inside said pair of housings, respectively, when said cellular phone is closed.

6. The cellular phone according to claim 1, wherein said two planar antennas are two planar inverse F-type antennas or two patch antennas.

7. The cellular phone according to claim 1, wherein an interval between said two planar antennas disposed within said pair of housings is at least three inches when said cellular phone is open.