MDS Receiver

• US 4,384,367 A
• Filed: 06/10/1981
• Issued: 05/17/1983
• Est. Priority Date: 02/12/1980
• Status: Expired due to Fees

• Current Assignee: Theta-Com of California
• Original Assignee: Theta-Com of California
• Inventors: Sigmon, Bernard E., King, Charles T.
• Primary Examiner(s): Chin, Tommy P.
• Application Number:
  US06/272,133
• Time in Patent Office: 706 Days
• Field of Search: 455/130, 455/325, 455/326, 455/327, 455/330, 455/333, 455/336, 455/337, 455/349, 455/313, 455/318, 455/319, 455/323, 455/331, 329/116, 329/122, 329/160
• US Class Current: 455/325
• CPC Class Codes: H01P 3/081 Microstriplines
• CPC Class Codes: H04B 1/26 for superheterodyne receivers multiple frequency-changing H03D7/16

Abstract

An improved low-cost microwave receiver is disclosed. The receiver is intended for use in the Multipoint Distribution Services (MDS) for the reception of television signals transmitted in the 2 to 2.5 GHz region. The receiver of the present invention is of the single-conversion superheterodyne type utilizing printed circuit and microstrip transmission line construction. Printed circuit board and microstrip transmission line construction permits low-cost fabrication without machined resonant cavities or waveguide components.

Claims

1. A single conversion superheterodyne type microwave receiver for frequency translating signals applied from a microwave antenna comprising:

input means for effecting an electrical connection to said microwave antenna;

first amplification means electrically connected to said input means for amplifying the electrical signal received by said microwave antenna;

a local oscillator including a step-recovery diode circuit and a first bandpass filter means, wherein said step-recovery diode circuit includes a crystal oscillator, a microstrip transmission line low-pass filter and matching structure and a step-recovery diode;

mixing means for electronically mixing the output of said first amplification means with that of said local oscillator to produce a second electrical signal;

second bandpass filter means electrically connected to said mixing means for passing predetermined frequencies of said second electrical signal to a second amplification means;

said second amplification means being electrically connected to said second bandpass filter means and being adapted to amplify the output thereof to predetermined levels;

power supply means for energizing said first and second amplification means, said mixing means, and said local oscillator; and

output means for effecting an electrical connection through said power supply means between said second amplification means and a utilization device.

2. The receiver of claim 1 wherein said first bandpass filter means consists of a plurality of electromagnetically coupled parallel, coplanar sections of microstrip transmission lines disposed in a predetermined spatial relationship.

3. A superheterodyne type microwave receiver for frequency translating signals applied from a microwave antenna comprising:

input means for effecting an electrical connection to said microwave antenna;

first amplification means electrically connected to said input means for amplifying the electrical signal received by said microwave antenna;

a local oscillator including a step-recovery diode circuit and a first bandpass filter means, said step-recovery diode circuit having a crystal oscillator, a microstrip transmission line low-pass filter and matching structure and a step-recovery diode, and said first bandpass filter means consisting essentially of a plurality of electromagnetically coupled parallel, coplanar sections of microstrip transmission lines disposed in a predetermined spatial relationship;

mixing means for electronically mixing the output of said first amplification means with that of said local oscillator to produce a second electrical signal, said mixing means consisting essentially of a quadrature hybrid microstrip transmission line having a dual-diode balanced mixer configuration;

second bandpass filter means electrically connected to said mixing means for passing predetermined frequencies of said second electrical signal to second amplification means;

said second amplification means being electrically connected to said second bandpass filter means and being adapted to amplify the output thereof to predetermined levels;

power supply means for energizing said first and second amplification means, said mixing means, and said local oscillator; and

output means for effecting an electrical connection through said power supply means between said second amplification means and a utilization device.