DESIGN & IMPLEMENTATION OF FRACTIONAL – N FREQUENCY SYNTHESIZER
محتوى المقالة الرئيسي
الملخص
This research involves design & implementation of fractional – N frequency synthesizer with the following specifications: Frequency range (2350– 2750) MHz,Step size (1 kHz), Switching time 8.9 μs, & phase noise @10 kHz = -115dBc & spurious -69 dBc The third order Fractional –N technique was chosen to satisfy the design requirements. In this system the modulator placed on digital phase-locked loop to control the fractional value of the
frequency division ratio thereby eliminating spurious and allowing good phase noise performance. The development in I.C. technology provides the simplicity in the design of fractional –N frequency synthesizer because it implements the phase frequency detector(PFD) , prescalar,modulator & reference divider in single chip. Therefore our system consists of a single chip contains (low phase noise PFD, charge pump, prescalar, modulator & reference divider), voltage controlled oscillator , loop filter & reference oscillator. The application of this synthesizer in frequency hopping systems, wireless transceivers ,GSM &
radar because it has high switching speed ,low phase noise & low spurious level.
تفاصيل المقالة
كيفية الاقتباس
تواريخ المنشور
المراجع
Conkling, Craig, (1998), Fractional-N synthesizers Trim current, phase noise”, Microwave and RF,Feb,.
Dean banerjee (2005), PLL performance , simulation & design” 4th edition, Goldberg, Bar-Giora., (1999), Digital frequency synthesis demystified, LLH,
J.A Crawford, (1994), Frequency synthesizer Design Handbook”, Artech house, Norwood ,.
J. Craeninkx & M. Steyaert, (1998), Wireless CMOS Frequency Synthesizer Design, Kluwer Boston ,.
Li Lin, (2000), Design Techniques for High Performance Integrated Frequency Synthesizers for Multi-standard Wireless Communication Applications, UNIVERSITY OF CALIFORNIA , phD, Thesis, Mike Curtin and Paul O’Brien. (1999), Phase locked loops for high frequency receivers and transmitters, Analog Dialogue Volume 33,.
The National Semiconductor series Data sheet, (2005).