| 摘要 |
PURPOSE: A code bit puncturing method is provided to reduce a frame error rate and transmission power by concentrically puncturing coded bits at start and end portions of a slot. CONSTITUTION: A convolutional code has such characteristics that a start portion state and ending portion state of code bits are fixed, based on which a Viterbi decoder can perform an accurate decoding. This means that bits of the start portion and bits of the ending portion have a less error rate than bits at the central portion. Accordingly it is preferred that the bits of the central portion are less punctured while the bits of the start and end portions are more punctured, in order to reduce a BER(Bit Error Rate) at the central portion. In this case, the bits at the start and end portions are punctured symmetrically from both side ends of the non-punctured coded bits of the central portion, the first coded bit of one slot is not punctured, and the number of non-punctured coded bits of the central portion is an odd number.
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