Portable wireless unit

• US 6,856,819 B2
• Filed: 03/07/2001
• Issued: 02/15/2005
• Est. Priority Date: 03/07/2000
• Status: Expired due to Term

• Current Assignee: Lenovo Innovations Ltd Hong Kong (Lenovo Group Ltd.)
• Original Assignee: NEC Corporation
• Inventors: Itoh, Ryoh
• Primary Examiner(s): Tran, Pablo N.
• Application Number:
  US09/800,538
• Publication Number:
  US 20010021643A1
• Time in Patent Office: 1,441 Days
• Field of Search: 455/13.3, 455/19, 455/25, 455/63.4, 455/82, 455/83, 455/562.1, 455/575.1, 455/575.7, 455/575.8, 455/90.3, 455/129, 455/128, 455/112, 455/113, 455/90, 455/575, 343/702, 343/700, 343/846, 343/824, 343/826, 343829-830
• US Class Current: 455/575.7
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 19/005 Patch antenna using one or more coplanar parasitic elements
• 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: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence

Abstract

A portable wireless unit of the invention has a first plane antenna smaller than an antenna size determined by a desired frequency, and a second plane antenna presenting an antenna size determined by the desired frequency on the whole by coupling with the first plane antenna.

Claims

1. A portable wireless unit comprising:

a first plane antenna, disposed on a circuit board incorporated within a casing of the wireless unit, for receiving a current for excitation thereof, the first plane antenna having a single resonant frequency and a smaller size than a size associated with a desired frequency; and

a parasitic second plane antenna, provided on an outer surface or inner surface of said casing, for presenting, when coupled together with said first plane antenna, an antenna size associated with said desired frequency.

2. The portable wireless unit of claim 1, wherein said first plane antenna is a plate-form inverted F type antenna, microstrip antenna, or chip antenna.

3. The portable wireless unit of claim 1, wherein said first plane antenna has a narrow band.

4. The portable wireless unit of claim 1, wherein said second plane antenna is disposed so as to be overlaid in a part or whole on said first plane antenna.