Phase correction amplifier and a feed-forward amplifier using the same

Abstract

A phase correction amplifier according to the present invention includes; a GaAs field effect transistor; and a Si field effect transistor or a Si bipolar transistor; wherein the GaAs field effect transistor and the Si field effect transistor or the Si bipolar transistor are cascade-connected each other through a variable attenuator. Further, a feed-forward amplifier includes the above phase correction amplifier and is constituted by: a distortion extracting loop consisting of a main amplifier signal path and a linear Signal path in order to distribute a transmission signal; a directional coupler for receiving an output signal through the main amplifier signal path and an output signal through the linear signal path; a distortion eliminating loop consisting of a sub-amplifier signal path and a linear signal path in order to input an output signal from the directional coupler: and a power compositor for receiving an output signal through the sub-amplifier signal path and an output signal through the linear signal path, and coupling both the output signals.

1 . A phase correction amplifier comprising: 
 a GaAs field effect transistor; and    a Si field effect transistor or a Si bipolar transistor;    wherein the GaAs field effect transistor and the Si field effect transistor or the Si bipolar transistor are cascade-connected each other.    
     
     
         2 . A phase correction amplifier comprising: 
 a GaAs field effect transistor; and    a Si field effect transistor or a Si bipolar transistor;    wherein the GaAs field effect transistor and the Si field effect transistor or the Si bipolar transistor are cascade-connected each other through a variable attenuator.    
     
     
         3 . A feed-forward amplifier comprising: 
 a distortion extracting loop consisting of a main amplifier signal path and a linear signal path in order to distribute a transmission signal;    a directional coupler for receiving an output signal through the main amplifier signal path and an output signal through the linear signal path;    a distortion eliminating loop consisting of a sub-amplifier signal path and a linear signal path in order to input an output signal from the directional coupler; and    a power compositor for receiving an output signal through the sub-amplifier signal path and an output signal through the linear signal path, and coupling both the output signals.    
     
     
         4 . A feed-forward amplifier as claimed in  claim 3 , wherein each of the main amplifier and the sub-amplifier is constituted by a phase correction amplifier comprising a GaAs field effect transistor, and a Si field effect transistor or a Si bipolar transistor, wherein the GaAs field effect transistor and the Si field effect transistor or the Si bipolar transistor are cascade-connected each other through a variable attenuator.  
     
     
         5 . A phase correction amplifier comprising: 
 a first transistor having a characteristic of an input level-to-an output phase in which, when the input level is increased, the output phase is gradually increased; and    a second transistor having a characteristic of an input level-to-an output phase in which, when the input level is increased, the output phase is gradually decreased;    wherein the first transistor and the second transistor are cascade-connected each other through an input level controller.    
     
     
         6 . A phase correction amplifier as claimed in  claim 5 , wherein said first transistor is a GaAs field effect transistor; said second transistor is a Si field effect transistor or a Si bipolar transistor; and said input level controller is a variable attenuator.