This paper introduces a kind of low phase noise frequency synthesizer which uses AT89S52 single chip processor to control digital phase-locked loop LMX2316,analyses the in-band phase noise and the relations between lock time and loop bandwidth of loop,discusses the design of the loop filter,finally obtains the results according with the analysis.
It consists of a LSI circuit MC145146 as the centre of this synthesizer,a reference oscillator,a dc amplifier,a loop filter,a voltagecontrolled oscillator,a doublemode freqrency pre-divider and a monolithic computer control system.
Based on charge pump phase locked loop (PLL) structure, the circuit consists of a voltage controlled oscillator (VCO), a divider, a phase/frequency detector, a charge pump, a loop filter, etc. The total chip size measures 1.1 mm× 0.8 mm.
The focus is on the circuit configuration and performance parameters of the basic analog units of the PLL: the stabilized bias unit, phase-frequency detector, charge pump, loop filter, and voltage-controlled oscillator (VCO).
Using Jones matrix analysis, a three-element fiber loop filter structure, performing as a Solc-type narrow band filter is designed and fabricated.
Up to 8-GHz Ultrafast Multi-Wavelength Routing Operation of Active Birefringent Fiber Loop Filter/Interleaver Using a Traveling-
Ultrafast multi-wavelength routing by an active birefringent fiber loop filter/interleaver is proposed and demonstrated.
Fully integrated frequency synthesizers are comprised of three major blocks: a voltage controlled oscillator (VCO), a phase locked loop (PLL) and a loop filter between them.