Wide Dynamic Range Broadband Current Mode Linear Detector Circuits for High Power Radio Frequency Power Amplifier

Abstract

A power detector with a detection signal input connectable to a source of a radio frequency signal and a detected power level output has a differential amplifier detector circuit with an input connected to the detection signal input and an output corresponding to the detected power level output. A feedback network is connected to the input and the output of the differential amplifier detector circuit. A mirror circuit is connected to the differential amplifier detector circuit. A root mean square current corresponding to a power level of the radio frequency signal from the source is mirrored and integrated, with a direct current voltage level being generated therefrom and output to the detected power level output.

What is claimed is: 
     
         1 . A power detector with a detection signal input connectable to a source of a radio frequency signal, and a detected power level output, the power detector comprising:
 a differential amplifier detector circuit with an input connected to the detection signal input, and an output corresponding to the detected power level output;   a feedback network connected to the input and the output of the differential amplifier detector circuit; and   a mirror circuit connected to the differential amplifier detector circuit, a root mean square current corresponding to a power level of the radio frequency signal from the source being mirrored and integrated, with a direct current voltage level being generated therefrom and output to the detected power level output, the direct current voltage being within a first predetermined voltage range between a low end and a high end and corresponding to the power level of the radio frequency signal.   
     
     
         2 . The power detector of  claim 1  further comprising a subtractor circuit connected to the output of the differential amplifier detector circuit, the direct current voltage level corresponding to the power level of the radio frequency signal being reduced by a predetermined amount to reduce the first predetermined voltage range to have a low end of zero. 
     
     
         3 . The power detector of  claim 1  wherein the differential amplifier detector circuit includes a first differential amplifier transistor and a second differential amplifier transistor, a gate of each of the first differential amplifier transistor and the second differential amplifier transistor corresponding to the input of the differential amplifier detector circuit. 
     
     
         4 . The power detector of  claim 3  wherein the first differential amplifier transistor is connected in a diode configuration. 
     
     
         5 . The power detector of  claim 3  wherein the second differential amplifier transistor is connected in a diode configuration. 
     
     
         6 . The power detector of  claim 3  wherein the mirror circuit includes a first mirror transistor connected to the first differential amplifier transistor, and a second mirror transistor connected to the second differential amplifier transistor. 
     
     
         7 . The power detector circuit of  claim 1  further comprising an electrostatic discharge circuit connected to the output of the differential amplifier detector circuit. 
     
     
         8 . A radio frequency front end circuit connectable to a source of a radio frequency signal, the radio frequency front end circuit comprising:
 a circuit output connectable to a radio frequency signal destination;   an amplifier circuit implemented and including input and an output, the input being connected to a source of a radio frequency signal;   a power detector including a differential amplifier circuit with a feedback network and a mirror circuit connected thereto, the differential amplifier circuit including an input connected to the output of the amplifier circuit, an output corresponding to the circuit output, a root mean square current corresponding to a power level of the radio frequency signal from the source being mirrored and integrated by the power detector to generate a direct current voltage level output to the circuit output, the direct current voltage being within a first predetermined voltage range between a low end and a high end and corresponding to the power level of the radio frequency signal; and   a coupler having a input port connected to the output of the amplifier circuit, a detector port connected to the input of the power detector, and a transmitted port connected to the circuit output.   
     
     
         9 . The front end circuit of  claim 8  further comprising a low drop out voltage regulator connected to a respective power supply input of the amplifier circuit and the power detector, and outputs a predetermined voltage from a variable voltage electrical power source. 
     
     
         10 . The front end circuit of  claim 9  wherein the variable voltage electrical power source is a battery. 
     
     
         11 . The front end circuit of  claim 8  wherein the amplifier circuit is a power amplifier, the radio frequency signal destination is an antenna, and the source of the radio frequency signal is a transceiver circuit. 
     
     
         12 . The front end circuit of  claim 8  wherein the amplifier circuit is a low noise amplifier, the radio frequency signal destination is a transceiver circuit, and the source of the radio frequency signal is an antenna. 
     
     
         13 . The front end circuit of  claim 8  further comprising a subtractor circuit connected to the output of the differential amplifier detector circuit, the direct current voltage level corresponding to the power level of the radio frequency signal being reduced by a predetermined amount to reduce the first predetermined voltage range to have a low end of zero. 
     
     
         14 . A radio frequency communications device comprising:
 a transceiver configured to process radio frequency signals;   an antenna configured to facilitate transmission and reception of the radio frequency signals;   an amplifier connected to the transceiver and the antenna and including an input and an output; and   a power detector including a differential amplifier circuit with a feedback network and a mirror circuit connected thereto, the differential amplifier circuit including an input connected to the output of the amplifier circuit, an output corresponding to the circuit output, a root mean square current corresponding to a power level of the radio frequency signal from the source being mirrored and integrated by the power detector to generate a direct current voltage level output to the circuit output, the direct current voltage being within a first predetermined voltage range between a low end and a high end and corresponding to the power level of the radio frequency signal.   
     
     
         15 . The radio frequency communications device of  claim 14  further comprising a directional coupler with an input port connected to the output of the amplifier, a detection port connected to an input of the power detector, and a transmission port connected to a selected one of the antenna and the amplifier. 
     
     
         16 . The radio frequency communications device of  claim 15  wherein the amplifier is a low noise amplifier with the transmission port of the directional coupler being connected to the transceiver and the input of the amplifier being connected to the antenna. 
     
     
         17 . The radio frequency communications device of  claim 15  wherein the amplifier is a power amplifier with the transmission port of the directional coupler being connected to the antenna and the input of the amplifier being connected to the transceiver. 
     
     
         18 . The radio frequency communications device of  claim 14  wherein the differential amplifier of the power detector includes a first differential amplifier transistor and a second differential amplifier transistor. 
     
     
         19 . The radio frequency communications device of  claim 18  wherein the first transistor is connected in a diode configuration. 
     
     
         20 . The radio frequency communications device of  claim 18  wherein the second transistor is connected in a diode configuration. 
     
     
         21 . The radio frequency communications device of  claim 18  wherein the mirror circuit includes a first mirror transistor connected to the first differential amplifier transistor, and a second mirror transistor connected to the second differential amplifier transistor. 
     
     
         22 . The radio frequency communications device of  claim 14  further comprising a subtractor circuit connected to the output of the differential amplifier detector circuit, the direct current voltage level corresponding to the power level of the radio frequency signal being reduced by a predetermined amount to reduce the first predetermined voltage range to have a low end of zero.