| 摘要 |
PURPOSE:To eliminate an error of decoding by storing a reception signal at intervals of a certain time and detecting the deviation of orthogonality of orthogonal/inphase components between the orthogonal modulator of a transmitter and the orthogonal detector of a receiver based on the deviation of amplitude to a known symbol in the reception signal and correcting the deviation of orthogonality of the reception signal with respect to the data decoding device used in a receiver for digital communication or the like. CONSTITUTION:A data signal including the known symbol is subjected to orthogonal modulation and is transmitted by a transmitter 1. This signal is subjected to orthogonal detection by a receiver 4 and is digitized by an A/D converter 7 and is stored in a memory 10. An I signal and a Q signal 14 of the known symbol are taken out of the memory 10 and are sent to an I and Q orthogonality deviation angle detecting circuit 15. This circuit 15 detects a deviation angle 16 of the orthogonal modulator and a deviation angle 17 of the orthogonal detector in accordance with received data and the known symbol. After an I and Q deviation angle correcting circuit 118 corrects deviation angles based on deviation angles 16 and 17 detected for reception data in the memory 10, a data decoding circuit 21 decodes reception data. |
