| 摘要 |
An object of the present invention is to provide a soft decision circuit by which the reception accuracy can be improved. Each of first and second receivers of the soft decision circuit includes a phase amount detector for detecting a phase amount of a receive signal, an I table and a Q table for converting the phase amount into orthogonal I/Q signals, an A/D converter for converting a receive level signal of the receive signal into a digital value, a log linear table for converting an output of the A/D converter into a squared value of a true value, and first and second multipliers for multiplying outputs of the I table and the Q table with the output of the log linear table to weight the outputs of the I table and the Q table. The soft decision circuit further comprises first and second adders for adding outputs of the first and second multipliers of the receivers of the 0-system and the 1-system, respectively, and a digital signal processing circuit for performing determination using outputs of the adders as soft decision information. |
