DEPUNCTURE STRUCTURE FOR RADIX-4 BRANCH METRIC OPERATION IN HIGH-RATE VITERBI DECODER AND METHOD OF THE SAME

摘要

PURPOSE: A depuncture structure for radix-4 branch metric operation in high-rate viterbi decoder and a method of the same are provided to enable a depuncture for a radix-4 branch metric operation of all punctured codes simply by using a clock a rate of which is equal to a clock rate of an inputted I, Q bit stream. CONSTITUTION: A first and a second FIFO(First In First Out)(110) store an I-signal sequentially. A third and a fourth FIFO(110) store a Q-signal sequentially. A first and a second multiplexor(120) multiplex a signal inputted from the first and the third FIFO(110). A third and a fourth multiplexor(120) multiplex a signal inputted from the second and the fourth FIFO(110). A first radix-2 branch metric calculator(130) performs a depuncture function about a signal inputted from the first and the second multiplexor(120). A second radix-2 branch metric calculator(130) performs a depuncture function about a signal inputted from the third and the fourth multiplexor(120).