| 摘要 |
PURPOSE:To halve required number of band-pass filters by constituting an energy detector after the band-pass filter in a spectrum analyzer and detector with a frequency discriminator so as to utilize not only energy level information but also frequency information thereby applying detection of 2<k> frequencies. CONSTITUTION:A signal received by a reception antenna 32 or a down-converter (option) is given to 2<k-1> sets of band-pass filters 50. Each filter is turned to separate 2<k> tones into 2<k-1> tones by two each. A signal through each band-pass filter 50 is given to each frequency discriminator 51. The frequency discriminator 51 outputs a voltage in response to the frequency of the output signal of the band-pass filter 50 to separate 2<k> tones as a whole. An output signal from each frequency discriminator 51 is given to each threshold or energy level detector 54. |
