Title :
A sine-output ROM-less direct digital frequency synthesiser using a polynomial approximation
Author :
Meenakarn, C. ; Thanachayanont, A.
Author_Institution :
Fac. of Eng., King Mongkut´´s Inst. of Technol., Bangkok, Thailand
Abstract :
This paper describes the design and implementation of a ROM-less sine-output direct digital frequency synthesiser by using a polynomial approximation, which provides a maximum error less than 2e-4 for phase values between 0 to π/2. The full-period sinewave is generated by using a quadrant-decode technique. This yields a very high spectral purity sinewave output. System-level approximation and experimental results using an FPGA show that the maximum harmonic distortion is less than -67.4 dBc and -64.8 dBc respectively.
Keywords :
circuit simulation; circuit testing; direct digital synthesis; field programmable gate arrays; harmonic distortion; logic design; polynomial approximation; waveform generators; FPGA implementation; ROM-less direct digital frequency synthesiser; full-period sinewave generation; maximum harmonic distortion; phase value maximum error; polynomial approximation synthesiser; quadrant-decode technique; sine-output DDFS; spectral purity; Design engineering; Digital integrated circuits; Equations; Frequency control; Frequency synthesizers; Information technology; Integrated circuit synthesis; Polynomials; Read only memory; Taylor series;
Conference_Titel :
Circuits and Systems, 2003. ISCAS '03. Proceedings of the 2003 International Symposium on
Print_ISBN :
0-7803-7761-3
DOI :
10.1109/ISCAS.2003.1205641
