A measuring unit converts a measuring signal into an intermediate frequency band of a predetermined bandwidth and detects the intermediate frequency band while a reception frequency is set variable by variably controlling a local oscillation frequency of a local oscillator. A waveform memory stores the magnitude of a detection signal output from the measuring unit in correspondence with the frequency. An analyzing unit analyzes a frequency component included in a signal to be measured, on the basis of a storage value of the waveform memory. An analysis target frequency data setting unit sets frequency data of a desired analysis target frequency or interval frequency data thereof. A sweep control unit changes the reception frequency of the measuring unit into the desired analysis target frequency corresponding to the frequency data set by the analysis target frequency data setting unit and outputs an address signal corresponding to the received analysis target frequency to the waveform memory every time a signal synchronized with an ON/OFF change of the signal to be measured is received.