| 摘要 |
PROBLEM TO BE SOLVED: To reduce the calculation amount of each correlator by improving resistivity against a noise. SOLUTION: This correlation circuit is provided with two correlators 9 and 10 corresponding to two kinds of diffusion codes in order to receive a signal to be transmitted in a spectrum diffusion communication system by using the two kinds of diffusion codes, and used for communication equipment for rail roads for identifying which of those diffusion signals is made correspond to a received signal by calculating the correlation value of the received signal and the diffusion codes. Those two correlators 9 and 10 are respectively divided into two correlators 9a and 9b and 10a and 10b so that two sets of correlator groups 9a, 10a; 9b, 10b corresponding to those two kinds of diffusion codes can be constituted. Then, received signals to be inputted to those two sets of correlator groups can be alternately switched by a switcher 11, and the absolute values of the output values of those two sets of correlator groups corresponding to the same diffusion codes are compared with each other by comparators 14a and 14b, and the larger values are outputted as correlation values corresponding to those diffusion code. |
