Anritsu Corporation

Osamu Tagiri

Etsuji Mesuda

An FM signal generator generates an FM signal obtained by frequency-modulating a reference frequency signal with a modulating frequency signal. A first mixer mixes the FM signal and an input signal having a predetermined carrier frequency and outputs a pair of frequency signals having sum and difference frequencies thereof. A first signal extracting unit extracts one of the pair of frequency signals as an intermediate frequency signal. A delay circuit delays the extracted intermediate frequency signal by a predetermined time. A second mixer mixes the delayed intermediate frequency signal and the FM signal and outputs a pair of frequency signals having sum and difference frequencies. A second signal extracting unit extracts the frequency signal of the pair of frequency signals which corresponds to the carrier frequency component as a phase-modulated signal. The modulation degree and modulation frequency in phase modulation for the phase-modulated signal can be set in wide ranges.

Phase modulator capable of individually defining modulation degree and

A signal detector includes a signal input section, a detector, and a converter. The signal input section inputs a high frequency signal to be measured. The detector detects the high frequency signal to be measured input by the signal input section. The converter amplifies the output from the detector and includes a variable gain preamplifier which has a first gain higher than a linear gain when the detecting output is smaller than a predetermined value and a second gain lower than the linear gain when the detecting output is larger than the predetermined value. A cable line transmits an output from the variable gain preamplifier of the converter of the signal detector. A measuring equipment body includes a decoder and an analyzer. The decoder amplifies an output from the variable gain preamplifier transmitted by the cable line and includes a variable gain main amplifier which has a first gain lower than a linear gain when an output from the variable gain preamplifier is smaller than a predetermined value and a second gain higher than a linear gain when the output from the variable gain preamplifier is larger than the predetermined value. The analyzer performs predetermined signal analysis for an output amplified by the variable gain main amplifier of the decoder.

Growing community of inventors

Atsugi, Japan

Osamu Tagiri