Working principle of Superheterodyne Type spectrum analyzer

- Sep 19, 2017 -

The function of the inverter is to transform the microwave signal into low frequency, for the frequency range of 9khz~22ghz Broadband spectrometer, its first inverter contains two mixers, one is for the low band of the fundamental mixer, the other is for the high band Harmonic mixer. The inverter also includes 6dB attenuator, single pole double throw switch and matching network. Therefore, the first frequency converter is one of the most important microwave components in wideband spectrum Analyzer.

The second frequency converter mainly completes the transformation of the first intermediate frequency to the second intermediate frequency. The frequency of the oscillator is 3.6GHz, which is obtained by 600MHz Octave.

The third frequency converter converts the second intermediate frequency into the third if, and the oscillator is 300MHz.

The step gain amplifier amplifies the third intermediate frequency signal, which is mainly used for the adjustment of the whole gain of the reference electric and attenuator.

Logarithmic amplifiers are the logarithm of the signal processing, expanding the measurement display dynamic range. The AC signal is transformed into a video signal by a geophone and then digitally quantified. The results of a variety of calculations will eventually be output to the monitor.