| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a novel method for determining whether a signal obtained by receiving a satellite signal for carrying a navigation message is decrypted correctly. <P>SOLUTION: A signal obtained by receiving a GPS satellite signal for carrying a navigation message is decrypted. Parity check processing is performed on decrypted data for the unit of a word in the navigation message specified to perform a parity check. Regarding a word from which no error is detected in the parity check processing, on the other hand, predetermined adequacy determination processing is performed thereon to determine adequacy of the decryption data, Then, decryption data of the words storing GPS satellite specific information therein and for which the absence of adequacy is determined in the adequacy determination processing are collated with each other. On the basis of the result of the collation, it is then determined whether the reception signal is decrypted correctly. <P>COPYRIGHT: (C)2013,JPO&INPIT |
