Miniaturized mobile radio receiver with dipole antenna

• US 4,577,195 A
• Filed: 12/19/1983
• Issued: 03/18/1986
• Est. Priority Date: 04/20/1982
• Status: Expired due to Term

• Current Assignee: Alcatel SA (Nokia Corporation)
• Original Assignee: International Standard Electric Corporation (ITT, Inc.)
• Inventors: Schwanitz, Manfred, Gaertner, Dietrich, Schenk, Joerg, Dressler, Wolfgang
• Primary Examiner(s): Lieberman, Eli
• Application Number:
  US06/568,239
• Time in Patent Office: 820 Days
• Field of Search: 343/702, 343/802, 455/270, 455/271, 455/351
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/243 with built-in antennas

Abstract

The miniaturized mobile radio receiver has a straight dipole antenna whose wires run along the edge of the printed-circuit board(s) of the radio receiver and are connected at their outer ends to conductive areas. The conductive strips on the circuit board(s) which run parallel to the antenna constitute a resistive-capacitive shunt and are, therefore, open in the vicinity of the antenna base to block the flow of RF signals.

Claims

1. In a miniaturized radio receiver with a housing, said receiver including at least one printed circuit board containing a plurality of components interconnected on said board by means of conductive strips, a dipole antenna having first and second wires directed parallel to one edge of said board with said first wire directed from the top of said edge towards the center of said board and said second wire directed from the bottom of said edge towards the center of said board to create a space between said wires near the center of said board to form a dipole antenna with said base of said antenna positioned near the center of said board, the combination therewith of capacitive loads for said wires comprising:

first and second conductive areas with said first area connected to said first wire at the top of said edge and positioned transverse to said first wire, with said second area connected to said second wire at the bottom of said edge and positioned transverse to said second wire, with each conductive area directed parallel to a corresponding side of said printed circuit board and spaced therefrom to create a predetermined capacitive value for each of said antenna wires, and means coupled to said conductive strips on said board to effectively open said conductive strips near said base of said dipole to block the flow of RF signals.

2. The combination according to claim 1, wherein said means includes a low capacitance and a low inductance resistor, inserted in each conductive strip running between highly resistive sources and loads.

3. The combination according to claim 1, wherein said means includes a resonant circuit inserted in each conductive strip running between low resistance sources and loads.

4. The combination according to claim 3, wherein each resonant circuit consists of a wire wound on a coil form.

5. The combination according to claim 2, wherein each resistor has a value of about 100K ohms.

6. The combination according to claim 3, wherein said resonant circuits are tuned to the frequency of reception of said radio receiver.

7. In a miniaturized radio receiver with a housing, said receiver including first and second printed circuit boards with said boards having equal length top and bottom edges and spaced apart in a parallel relation with said top and bottom edges aligned with, one of said boards being of a greater length than said other, with both of said boards supporting a plurality of components interconnected by conductive strips, a dipole antenna having first and second wires, with said first wire directed parallel to a side edge of said first board and said second wire directed parallel to a corresponding side edge of said second board to form said dipole antenna with the base of said dipole positioned near the bottom edge of said smaller board, the combination therewith of capacitive loads for said wires comprising:

first and second conductive areas with said first area connected to said first wire and directed transverse to the same and parallel to an edge of said first board, with said second conductive area connected to said second wire and directed parallel to an edge of said second board with said areas creating predetermined capacitive values for each of said wires and means coupled to said conductive strips on said boards to effectively open said conductive strips in the vicinity of said antenna base to block the flow of RF signals.

8. The combination according to claim 7, further including a third conductive area located between the space between said first and second boards and connected to said conductive area associated with said second smaller board, both areas connected with the end of said second wire.

9. The combination according to claim 7, wherein said means to open said conductive strips includes a low capacitance, low inductance resistor inserted in each conductive strip running between highly resistive sources and loads.

10. The combination according to claim 7, wherein said means to open said conductive strip includes a low capacitance, low inductance resistor inserted in each conductive strip running between low resistive sources and loads.

11. A dipole antenna structure for a miniaturized radio received or the like, said receiver of the type having at least one printed circuit board for containing a plurality of components interconnected on said board by means of conductive strips, said board being generally of a rectangular configuration having parallel top and bottom surfaces interconnected by parallel side surfaces, comprising:

a first wire directed along a side edge from a top surface towards the center and a second wire directed along said side edge from said bottom surface towards said center, with each wire spaced from said edge at the same distance and directed relatively parallel thereto, with said wires forming a dipole with the base of said dipole positioned near the center of said board and first and second conductive areas each directed parallel to and spaced from an associated top and bottom edge, with the end of said first wire connected to said first area at said top surface and with the end of said second wire connected to said second area at said bottom surface, with said conductive areas creating a predetermined capacitive value for each of said wires and means coupled to said conductive strips on said board to effectively open said conductive strips at the vicinity of said dipole base to block the flow of RF signals.