Detector circuit and system for a wireless communication

Abstract

Provided are a detector circuit which has a simple circuit configuration, is capable of indicating an accurate power according to a load fluctuation of a radio frequency power amplifier or a difference in a modulation mode, and can be easily incorporated in the radio frequency power amplifier, and a wireless communication system using the detector circuit. The detector circuit 10 includes a detecting resistor 11 for detecting a part of a current flowing from a bias circuit 6 , and a current-voltage conversion circuit 12 for converting a current obtained through the detecting resistor 11 into a voltage. A current supplied from the bias circuit 6 to the amplifying transistor 1 is detected, so that an output current from the amplifying transistor 1 fluctuates when a load on the radio frequency power amplifier fluctuates, and an input current and a current from the bias circuit fluctuate in proportion to the output current from the amplifying transistor 1 , whereby an outputted detection voltage can follow a load fluctuation on the radio frequency power amplifier.

1 - 18 . (canceled) 
     
     
         19 . A detector circuit used for a power amplifier circuit including an amplifying transistor and a bias circuit supplying the amplifying transistor with a bias current, the detector circuit comprising:
 a current partition transistor having a collector and a base connected to a collector and a base, respectively, of an emitter follower transistor of the bias circuit supplying a base of the amplifying transistor with a bias current;   a resistor, having one end connected to an emitter of the current partition transistor, for detecting a part of an emitter current supplied from the current partition transistor; and   a current-voltage conversion circuit, connected to the other end of the resistor, for coverting a current flowing through the resistor into a voltage.   
     
     
         20 . The detector circuit according to  claim 19 , wherein a bipolar transistor is employed as the current-voltage conversion circuit. 
     
     
         21 . The detector circuit according to  claim 19 , wherein a field effect transistor is employed as the current-voltage conversion circuit. 
     
     
         22 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current; and   a detector circuit according to  claim 19 , which is connected to the driver stage bias circuit.   
     
     
         23 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current; and   a detector circuit according to  claim 19 , which is connected to the driver stage bias circuit.   
     
     
         24 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current; and   a detector circuit according to  claim 19 , which is connected to the final stage bias circuit.   
     
     
         25 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current; and   a detector circuit according to  claim 19 , which is connected to the final stage bias circuit.   
     
     
         26 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a first detector circuit according to  claim 19 , which is connected to the driver stage bias circuit; and   a second detector circuit according to  claim 19 , which is connected to the final stage bias circuit.   
     
     
         27 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a first detector circuit according to  claim 19 , which is connected to the driver stage bias circuit; and   a second detector circuit according to  claim 19 , which is connected to the final stage bias circuit.   
     
     
         28 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a first detector circuit according to  claim 19 , which is connected to the driver stage bias circuit; and   a second detector circuit according to  claim 19 , which is connected to the final stage bias circuit.   
     
     
         29 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a first detector circuit according to  claim 19 , which is connected to the driver stage bias circuit; and   a second detector circuit according to  claim 19 , which is connected to the final stage bias circuit.   
     
     
         30 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a detector circuit according to  claim 19 , which is connected to the final stage bias circuit, and   a control circuit for controlling the bias currents from the driver stage bias circuit and the final stage bias circuit in accordance with a value of a voltage outputted from the detector circuit.   
     
     
         31 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a detector circuit according to  claim 19 , which is connected to the final stage bias circuit, and   a control circuit for controlling the bias currents from the driver stage bias circuit and the final stage bias circuit in accordance with a value of a voltage outputted from the detector circuit.   
     
     
         32 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a DC-DC converter for supplying each of an output terminal of the driver stage amplifier circuit and an output terminal of the final stage amplifier circuit with a voltage;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a detector circuit according to  claim 19 , which is connected to the final stage bias circuit, and   a control circuit for controlling, in accordance with a value of a voltage outputted from the detector circuit, the bias currents from the driver stage bias circuit and the final stage bias circuit, and the voltages outputted from the DC-DC converter.   
     
     
         33 . A wireless communication system using a radio frequency power amplifier including a two stage amplifier circuit, the wireless communication system comprising:
 a driver stage amplifier circuit for amplifying a radio frequency signal;   a final stage amplifier circuit for amplifying an output from the driver stage amplifier circuit;   a DC-DC converter for supplying each of an output terminal of the driver stage amplifier circuit and an output terminal of the final stage amplifier circuit with a voltage;   a driver stage bias circuit for supplying an input terminal of the driver stage amplifier circuit with a bias current;   a final stage bias circuit for supplying an input terminal of the final stage amplifier circuit with a bias current;   a detector circuit according to  claim 19 , which is connected to the final stage bias circuit, and   a control circuit for controlling, in accordance with a value of a voltage outputted from the detector circuit, the bias currents from the driver stage bias circuit and the final stage bias circuit, and the voltages outputted from the DC-DC converter.