Title :
A new FM modulator using phase unstable PLL (PU-PLL)
Author :
Takagi, Tasuku ; Ohguchi, Junji
Author_Institution :
Tohoku University, Sendai, Japan
Abstract :
A phase-locked loop (PLL) with a second-order low-pass filter can oscillate with the frequency nearly equal to the filter cutoff. By modulating the amplitude of the oscillation, a stable frequency modulated signal can be obtained at the output of a voltage-controlled oscillator (VCO).
Keywords :
Adaptive filters; Amplitude modulation; Chirp modulation; Cutoff frequency; Frequency modulation; Laplace equations; Low pass filters; Phase locked loops; Phase modulation; Voltage-controlled oscillators;
Journal_Title :
Proceedings of the IEEE
DOI :
10.1109/PROC.1981.12210
