| 摘要 |
PROBLEM TO BE SOLVED: To always output a transmission signal and to reduce the number of the amplitude levels of the transmission signal by adding a rectangular wave having a period equal to the chip interval of a pseudo noise code to a time area where pseudo noise in the transmission signal does not exist when pseudo noise codes are not overlapped with each other and always setting the amplitude width of the transmission signal after addition to be a binary. SOLUTION: The periodical rectangular wave is inserted into the area where the pseudo noise code does not exist and it is added. An amplitude value is set to be a binary similar to the pseudo noise code even in this area to set a state where a zero level does not exist. Thus, a non-linear saturation-type amplifier can be used and gain control is not necessary. When the same pseudo noise codes are correlated with each other, a correlation value shoes a sharp peak when a time difference is zero and it becomes only ±1 at the time except for the case. The mutual correction of the next pseudo noise signal and one period of a rectangular wave pulse forming one chip is obtained by shifting a characteristic at the time of half chip, inverting it and adding it to an original characteristic. |
