Timing Recovery In Next-generation Versatile Disc

The Next-Generation Versatile Disc (NVD) is a new CD standard of China who has the intellectual property rights of NVD. Compared to DVD, the recording density of NVD has been greatly improved, which leads to the increase of InterSymbol Interference (ISI). As a result of the ISI coupled by the noise, the bit error rate (BER) of NVD system increases. Because the sampling clock of NVD is independent of symbol clock, timing recovery has to be applied to obtain the signal data sampled at the best decision time.This paper describes the basic principles of timing recovery, and shows the block diagram of timing recovery, including three main modules: timing error detection, interpolation controlling and interpolation. A timing error detecting algorithm including Kalman filtering is analyzed, and a recursive algorithm for interpolation controlling and the basic equation of digital filter for interpolation are derived.After briefly introducing the characteristics of NVD, the paper shows the necessity of timing recovery. A scheme of the NVD timing recovery implementation is analyzed: the square timing error detection including a Kalman filter, the recursive algorithm proposed by M. Moeneclaey, and the linear or cubic interpolation. Then the framework of NVD timing recovery is showed.In this paper, the C++ language is used to simulate the NVD timing recovery. The code runs on Microsoft Visual Studio 2010 building environment on Windows XP operating system. The flow diagrams and algorithms of timing error detecting, interpolation controlling and interpolation are described respectively.According to the timing recovery algorithm the article has achieved, the effects of timing recovery on the system BER are analyzed under different jitters, Gaussian white noises and sinusoidal disturbances. The Matlab is used to draw waveforms. Finally, the results show that timing recovery can effectively reduce the NVD BER.