Structure of reception frequency converting portion in a multi-band microwave detector

• US 5,341,138 A
• Filed: 03/17/1993
• Issued: 08/23/1994
• Est. Priority Date: 03/24/1992
• Status: Expired due to Fees

• Current Assignee: Yupiteru Industries Co., Ltd.
• Original Assignee: Yupiteru Industries Co., Ltd.
• Inventors: Hatasa, Takeshi, Ono, Hisao
• Primary Examiner(s): Barron, Jr., Gilberto
• Application Number:
  US08/032,261
• Time in Patent Office: 524 Days
• Field of Search: 342/20, 333/212, 333/230, 455/319, 331/107 DP
• US Class Current: 342/20
• CPC Class Codes: G01S 13/92 for velocity measurement
• CPC Class Codes: G01S 7/032 Constructional details for solid-state radar subsystems
• CPC Class Codes: H01Q 1/247 with frequency mixer, e.g. for direct satellite reception or Doppler radar
• CPC Class Codes: H04B 1/26 for superheterodyne receivers multiple frequency-changing H03D7/16

Abstract

A structure of a reception frequency converting portion of a multi-band microwave detector, and including a microwave circuit comprises a horn antenna, two-port cavity integrally formed with the horn antenna and having one port communicated with a throat portion of the horn antenna, one-port cavity integrally formed with the two-port cavity and communicated with the other port of the two-port cavity, a mixer diode located at the throat portion of the horn antenna, a first local oscillator arranged within the two-port cavity, and a second local oscillator arranged within the one-port cavity.

Claims

1. A structure of a reception frequency converting portion of a multi-band microwave detector, and including a microwave circuit comprising:

a horn antenna;

two-port cavity integrally formed with said horn antenna and having one port communicated with a throat portion of said horn antenna;

one-port cavity integrally formed with said two-port cavity and communicated with the other port of said two-port cavity;

;

a mixer diode located at said throat portion of said horn antenna;

a first local oscillator provided within said two-port cavity; and

a second local oscillator provided within said one-port cavity.

2. A multi-band microwave detector comprising:

a main body defining a horn antenna, a first cavity communicated with said horn antenna through a throat portion, and a second cavity communicated with said first cavity;

a microwave circuit including a mixing means located in said throat portion, a first local oscillator located within said first cavity and a second local oscillator located within said second cavity, said first and second local oscillators being operated in time sharing basis.

3. A multi-band microwave detector as set forth in claim 2, wherein said first and second local oscillators are installed on a single printed circuit board disposed in both of said first and second cavities.

4. A multi-band microwave detector as set forth in claim 2, which further comprises a plurality of adjusting elements mounted on said main body for adjustment of oscillation characteristics of respective of first and second oscillators.

5. A multi-band microwave detector as set forth in claim 4, wherein said adjusting elements include a first adjusting element located in opposition to said first oscillator and a second adjusting element located in opposition to said second oscillator and a third adjusting element located close to said mixing means.

6. A multi-band microwave detector as set forth in claim 2, said first and second cavities having a configuration in which said first cavity serves as a resonating element disposed between said second oscillator and said mixing means while said second oscillator is active, and said second cavity serves as a non-reflectively terminated impedance while said first oscillator is active.

7. A multi-band microwave detector as set forth in claim 6, wherein said first cavity serves as a waveguide transmitting line having a matched impedance, and the matched impedance waveguide transmitting line serves as a waveguide resonating element of a waveguide filter which eliminates undesirable frequency signals.