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A Numerically Controlled Oscillator for Multi-Carrier Channel Separation in Cdma2000 3X  

Lim In-Gi (한국전자통신연구원 기반기술연구소 고집적SoC연구부)
Kim Whan-Woo (충남대학교 전자공학과)
Publication Information
The Journal of Korean Institute of Communications and Information Sciences / v.29, no.11A, 2004 , pp. 1271-1277 More about this Journal
Abstract
We propose a foe phase tuner and a rounding processor for a numerically controlled oscillator (NCO), yielding a reduced phase error in generating a digital sine waveform. By using the fine Phase tuner Presented in this paper, when the ratio of the desired sine wave frequency to the clock frequency is expressed as a fraction, an accurate adjustment in representing the fractional value can be achieved with simple hardware. In addition, the proposed rounding processor reduces the effects of phase truncation on the output spectrum. Logic simulation results of the NCO for multi-carrier channel separation in cdma2000 3X multi-carrier receive system using these techniques show that the noise spectrum and mean square error (MSE) are reduced by 8.68 dB and 5.5 dB, respectively compared to those of truncation method and 2.38 dB and 0.83 dB, respectively, compared to those of Paul's scheme.
Keywords
NCO; numerically controlled oscillator; fine phase tuner; rounding processor;
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