MMIC transceiver and low cost subharmonically driven microwave receiver

• US 7,046,959 B2
• Filed: 01/07/2003
• Issued: 05/16/2006
• Est. Priority Date: 09/05/2002
• Status: Expired due to Fees

• Current Assignee: Reveal Imaging, LLC
• Original Assignee: Xytrans, Inc.
• Inventors: Ammar, Danny F., Stahly, Stephen A.
• Primary Examiner(s): Gesesse, Tilahun
• Application Number:
  US10/337,968
• Publication Number:
  US 20040048588A1
• Time in Patent Office: 1,225 Days
• Field of Search: 455/3.02, 455/12.1, 455/13.1, 342/354, 333/247, 333/204
• US Class Current: 455/13.1
• CPC Class Codes: H04B 7/18517 Transmission equipment in earth stations
• CPC Class Codes: H04B 7/18528 Satellite systems for providing two-way communications service to a network of fixed stations, i.e. fixed satellite service or very small aperture terminal [VSAT] system

Abstract

A receiver is operable at microwave frequencies and includes a substrate and waveguide-to-microstrip transition formed on the substrate for receiving microwave radio frequency (RF) signals. Surface mounted receiver components are interconnected with microstrip formed on the substrate and receive the RF signals from the waveguide-to-microstrip transition and convert the signal to an intermediate frequency (IF) for further processing. The surface mounted receiver components include a mixer circuit that receives a local oscillator (LO) signal and RF signal to produce the IF signal. A diplexer circuit and a temperature compensated attenuator circuit received the IF signal from the mixer and attenuates the IF signal to provide high signal linearity and high order modulation.

Claims

1. A receiver operable at microwave frequencies comprising:

a substrate;

a waveguide-to-microstrip transition formed on the substrate for receiving microwave radio frequency (RF) signals;

surface mounted receiver components and interconnecting microstrip formed on the substrate that receive the RF signals from the waveguide-to-microstrip transition and convert the signal to an intermediate frequency (IF) for further processing, and comprising

a mixer circuit that receives a local oscillator (LO) signal and RF signal to produce the IF signal;

a diplexer circuit and a temperature compensated attenuator circuit that receive the IF signal from the mixer and attenuates the IF signal to provide high signal linearity and high order modulation, wherein the diplexer circuit receives the IF signal from the mixer circuit and passes the signal to the temperature compensated attenuator circuit;

a controller and temperature compensation circuit operatively connected to the temperature compensated attenuator circuit for temperature compensating any attenuation to the IF signal; and

a receive signal strength indicator (RSSI) circuit that couples a portion of the IF signal after the diplexer and temperature compensated attenuator circuit and operatively connected to the controller and in feedback to the mixer circuit for allowing the controller to adjust circuit operation and ensure high signal linearity and high order modulation.

2. A receiver according to claim 1, and further comprising a gain equalizer circuit for receiving the IF signal from the temperature compensated attenuator circuit.

3. A receiver according to claim 1, and further comprising an amplifier circuit that amplifies the IF signal before passing through the diplexer circuit and temperature compensated attenuator circuit.

4. A receiver according to claim 1, and further comprising an amplifier circuit that receives the IF signal after passing through the diplexer circuit and temperature compensated attenuator circuit.

5. A receiver according to claim 1, wherein the waveguide-to-microstrip transition comprises a metallic housing, ground layer thereon, a substrate over the ground layer, and backshort and microstrip line operably formed as a waveguide launch.

6. A receiver according to claim 5, wherein the microstrip line further comprises copper having a thinner nickel layer on at least a portion of the copper.

7. A receiver according to claim 5, and further comprising ground vias that extend around the backshort to aid in the transition.

8. A receiver according to claim 1, wherein said receiver is operable as a VSAT transceiver.

9. A receiver operable at microwave frequencies comprising:

a substrate;

a waveguide-to-microstrip transition formed on the substrate for receiving microwave radio frequency (RF) signals;

surface mounted receiver components and interconnecting microstrip formed on the substrate that receive the RF signals from the waveguide-to-microstrip transition and convert the signal to an intermediate frequency (IF) for further processing, and comprising

a local oscillator circuit that generates a local oscillator (LO) signal,

a low pass filter that receives the LO signal;

a bandpass filter that receives the RF signal;

a mixer circuit that receives the local oscillator (LO) signal from the low pass filter and the RF signal from the bandpass filter to produce the IF signal,

a diplexer circuit and temperature compensated attenuator circuit that receive the IF signal from the mixer and attenuates the IF signal to provide high signal linearity and high order modulation, wherein the diplexer circuit receives the IF signal from the mixer circuit and passes the signal to the temperature compensated attenuator circuit;

a controller and temperature compensation circuit operatively connected to the temperature compensated attenuator circuit for temperature compensating any attenuation to the IF signal; and

a receive signal strength indication (RSSI) circuit that couples a portion of the IF signal after the diplexer and temperature compensated attenuator circuit and operatively connected to the controller for allowing the controller to adjust circuit operation and ensure high signal linearity and high order modulation.

10. A receiver according to claim 9, wherein said mixer circuit further comprises a Field Effect Transistor (FET) and gate bias circuit and a drain bias circuit connected thereto and forming a mixer output at the drain and connected to the dip/lexer circuit and temperature compensated attenuator circuit.

11. A receiver according to claim 9, wherein the surface mounted receiver components are operable as a harmonic load at the output of the Field Effect Transistor.

12. A receiver according to claim 9, and further comprising a gain equalizer circuit for receiving the IF signal from the temperature compensated attenuator circuit.

13. A receiver according to claim 9, and further comprising an amplifier circuit that amplifies the IF signal before passing through the diplexer circuit and temperature compensated attenuator circuit.

14. A receiver according to claim 9, and further comprising an amplifier circuit that receives the IF signal after passing through the diplexer circuit and temperature compensated attenuator circuit.

15. A receiver according to claim 9, wherein the waveguide-to-microstrip transition comprises a metallic housing, ground layer thereon, a substrate over the ground layer, and backshort and microstrip line operably formed as a waveguide launch.

16. A receiver according to claim 15, wherein the microstrip line further comprises copper having a thinner nickel layer on at least a portion of the copper.

17. A receiver according to claim 15, and further comprising ground vias that extend around the backshort to aid in the transition.

18. A receiver according to claim 9, wherein said receiver is operable as a VSAT transceiver.