Microwave/millimeter-wave integrated circuit

Abstract

A microwave/millimeter-wave integrated circuit realizes stable oscillation by reducing time-base variation in load impedance. This IC connects an oscillator to the input terminal of a lange coupler, and connects to the isolation port of the lange coupler a terminating resistor with resistance equal to the load impedance connected to the output terminals of the lange coupler. This stabilizes load impedance to the oscillator, and reduces variation in the oscillation frequency as a result of changes in load impedance.

What is claimed is:  
     
         1 . A microwave/millimeter-wave integrated circuit for generating and outputting a high frequency signal in the microwave/millimeter-wave band, comprising: 
 an oscillator for generating and outputting a high frequency signal in the microwave/millimeter-wave band; and    a lange coupler having an input terminal to which is input the high frequency signal output from the oscillator, an output terminal, and an isolation terminal to which is connected a terminating resistance equal to a load impedance connected to the output terminal.    
     
     
         2 . The microwave/millimeter-wave integrated circuit according to  claim 1 , further comprising an amplifier for amplifying and outputting a high frequency signal output from the lange coupler.  
     
     
         3 . A microwave/millimeter-wave integrated circuit for generating and outputting a high frequency signal in the microwave/millimeter-wave band, comprising: 
 an oscillator for generating and outputting a high frequency signal in the microwave/millimeter-wave band; and    a directional coupler having a main signal line to one end of which the high frequency signal from the oscillator is input, and to the other end of which is connected a terminating resistor of a predetermined resistance.    
     
     
         4 . The microwave/millimeter-wave integrated circuit according to  claim 3 , further comprising an amplifier for amplifying and outputting a high frequency signal output from a sub line of the directional coupler.  
     
     
         5 . A microwave/millimeter-wave integrated circuit for generating and outputting a high frequency signal in the microwave/millimeter-wave band, comprising: 
 an oscillator for generating and outputting a high frequency signal in the microwave/millimeter-wave band;    a directional coupler having a main signal line to one end of which is input the high frequency signal from the oscillator;    an amplifier for amplifying and outputting a high frequency signal input from the oscillator through the main signal line of the directional coupler, and having a bias input terminal to which bias is input from an external source; and    a phase detecting integrated circuit for phase detecting a signal reflection from the amplifier input through the sub line of the directional coupler, generating an inverse phase signal of which the phase is opposite the detected phase, and outputting the inverse phase signal to a bias input terminal of the amplifier.