Verfahren und Vorrichtung zum Demodulieren von amplitudenmodulierten Hochfrequenzsignalen
Date Issued
1996
Author(s)
Perthold, R.
Gerhaeuser, H.
Patent No
1995-19535356
Abstract
The method involves preparing a local oscillator signal (110) with a frequency corresp. to that of the amplitude modulated signal (102). The local oscillator signal is phase modulated, and both the amplitude modulated and the phase modulated signals are mixed. The product of mixing the signals is passed through a low pass filter, and the demodulated signal is generated on the basis of the detected amplitude values of the low pass filtered mixing product. The phase modulation of the local oscillator signal involves a discreet phase shift of the signal by phase steps of 90 or 45 degrees. ADVANTAGE - Accurate demodulation at low cost.