Paper Presentation & Seminar On "Fuzzy Logic" PDF Download
Paper Presentation & Seminar On "Fuzzy Logic"
Phased locked loop operates on the principle of feed back control, except that the feed back quantity is not the amplitude but the phase of the sinusoidal input signal. If the input sinusoid is noise, the PLL not only tracks the sinusoidal signal, but also cleans it up. The PLL can be used as an FM demodulator and frequency synthesizer. The PLL, being a relatively inexpensive integrated circuit, has become one of the most frequently used communication circuit. PLL is also used in space-vehicle-to-earth data links where there is a premium on transmitter Weight or where the loss along the transmission path is very large.
A classic PLL consists of a voltage controlled oscillator (VCO), a multiplier serving as a phase detector (PD) and a low pass filter. The VCO adjusts its own frequency until it is equal to that of the input sinusoidal signal such that the frequency and phase of the two signals are in synchronism.