Short wave transmission method and apparatus therefor

• US 5,842,135 A
• Filed: 05/15/1996
• Issued: 11/24/1998
• Est. Priority Date: 06/09/1995
• Status: Expired due to Fees

• Current Assignee: Iwao Ishijima, Masao Tsujita
• Original Assignee: Iwao Ishijima, Masao Tsujita
• Inventors: Ishijima, Iwao
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US08/647,798
• Time in Patent Office: 923 Days
• Field of Search: 455/52.1, 455/107, 455/110, 455/504, 342/361, 342/363, 342/365, 343/796, 343/797, 343/810, 343/816, 343/895, 343/822, 343/860
• US Class Current: 455/504
• CPC Class Codes: H04B 14/08 characterised by the use of a sub-carrier

Abstract

In a short wave transmission method, a carrier in a short wave band is circularly polarized and radiated from an antenna, thereby removing an influence of fading. A short wave transmission apparatus has a transmission apparatus including a carrier generation unit, a subcarrier generation unit, a first mixer, a phase shifter, a second mixer, and two orthogonal dipole antennas. The carrier generation unit generates a carrier in a short wave band. The subcarrier generation unit generates a subcarrier. The first mixer receives the carrier and the subcarrier. The phase shifter phase-shifts the subcarrier generated from the subcarrier generation unit by π/2. The second mixer receives the carrier and a subcarrier which is phase-shifted by π/2 by the phase shifter.

Claims

1. A short wave transmission apparatus having a transmission apparatus comprising:

carrier generation means for generating a carrier in a short wave band;

amplification means for amplifying the carrier;

means for dividing the amplified carrier;

a coaxial cable; and

two orthogonal dipole antennas,

wherein said dipole antennas are connected to a coaxial cable having a length for delaying a phase to be supplied to one antenna element by π

/2 with respect to that to the other antenna element.

2. A short wave transmission apparatus having a transmission apparatus comprising:

carrier generation means for generating a carrier in a short wave band;

amplification means for amplifying the carrier;

impedance matching means for outputting the amplified carrier; and

a helical antenna,

wherein the carrier is input from said impedance matching means to said helical antenna, thereby radiating a circularly polarized wave.