Iterative Turbo Decoder Analysis Based on Gaussian Density Evolution
نویسندگان
چکیده
nels was computed. Wiberg [3] in his dissertation has W e model the density of extrinsic information in iterative turbo decoders by Gaussian density functions. This model is verified by experimental measurements. We consider evolution of these density functions through the iterative turbo decoder as a nonlinear dynamical system with feedback. Iterative decoding of turbo codes and of serially concatenated codes are analyzed based on this method. Many mysteries of turbo codes can be explained based on this analysis. For example we can explain why certain codes converge better with iterative decoding than more powerful codes which are only suitable for max imum likelihood decoding. The roles of systematic bits and of recursive convolutional codes as constituents of turbo codes are explained based on this analysis.
منابع مشابه
Iterative turbo decoder analysis based on density evolution
We track the density of extrinsic information in iterative turbo decoders by actual density evolution, and also approximate it by consistent Gaussian density functions. The approximate model is verified by experimental measurements. We view the evolution of these density functions through an iterative decoder as a nonlinear dynamical system with feedback. Iterative decoding of turbo codes and o...
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