Research On Power Amplifier Waveform Measurement Technology Based On Harmonic Mixing

With the continuous development of communication technology,power amplifiers are becoming more important than before.For traditional power amplifier circuit analysis,the frequency domain output mainly concern.The time-domain waveform of the power amplifier circuit is not very concerned,but for some power amplifiers,it is necessary to concern the time-domain waveform of power amplifiers output,so that the circuit waveform of the signal in the transistor meets the expected requirements,so that the voltage and current on the transistor meet our requirements,it can reducing the power consumption of the transistor and increasing the power amplifier.For some power amplifiers,it is usually necessary to control the harmonics of the signal.This method is called harmonic control.This method can achieve a high-efficiency output of the power amplifier.For F or F-1 power amplifiers,it is necessary to control the signal's second and third harmonics to achieve 100% efficiency in theory;to improve the efficiency of the power amplifier,Only if the voltage and current are not overlapped,the power consumption on the transistor can be reduced,thereby improving the efficiency of the power amplifier.Various continuous power amplifiers were developed based on harmonic control methods,and the harmonic control methods increase the impedance solution space of power amplifiers and simplify the design of power amplifiers.Methods based on harmonic control must obtain the time-domain waveform of the power amplifier to determine the work of the power amplifier and then optimize the power amplifier.For the power amplifier,the power amplifier nonlinear is very strong,when the signal input is a single-tone signal,the signal output is often a multi-tone signal.The signal spectrum is very large,and it is difficult to use direct sampling or band-pass sampling to get s accurate signal time-domain waveform.his article uses a harmonic mixing method to convert high-frequency signals to low-frequency signals for signal sampling and analysis,The main work of this paper is as follows:First,design a harmonic circuit to mix,pass the high-frequency signal through the mixer to the lower frequency signal,thereby reducing the sampling rate of the signal.This circuit is mainly divided into drive circuit,amplitude equalizer,harmonic generator,coupling,And mixer circuit.The drive circuit drives the harmonic generation circuit to make the harmonic output signal more balanced through the equalization circuit.The large signal of the amplifier is coupled to the mixer circuit through the coupling circuit.After the harmonic mixing,the low-frequency signal is collected and the collected signal is Perform correction and recovery.Second,the collected signals are mainly restored and corrected to obtain accurate signal spectrum information.Several common signal spectrum correction methods are considered,and a new type of signal spectrum correction method,namely the all-phase Fourier transform method,is adopted to realize the correction.The accurate correction of the signal spectrum,this method is analyzed,because this method adopts the all-phase processing method,it accelerates the falling speed of the sidelobe line of the single-tone signal.Within the range of the signal mainline,the signal phase is almost No change,the accuracy of signal measurement is improved.Finally,the output sampling of the overall circuit is corrected to get the final output of the signal...