| 摘要 |
PROBLEM TO BE SOLVED: To improve reception characteristics by optimizing a parameter in the case of using a normalized UMP BP method, an offset UMP BP method or the like.SOLUTION: A multipath component power measurement section 21 of a parameter optimum value decision section 8-1 measures a D/U ratio of multipath component power as data on a state of a transmission path on the basis of a transmission path response, and a parameter decision section 23 extracts control information such as a carrier modulation system and an encoding rate from TMCC, and reads out a parameter &bgr; corresponding to the carrier modulation system, the encoding rate and the D/U ratio of the multipath component power from a DB 22 to decide an optimum value of the parameter &bgr;. The optimum value of the parameter &bgr; can be adaptively changed according to the D/U ratio of the multipath component power reflecting the state of the transmission path in the case of using the offset UMP BP method, which suppresses an effect of approximation to reduce degradation in a UMP BP method, as an LDPC decoding algorithm of an LDPC code decoding section 19. |
