| 摘要 |
PURPOSE:To realize synchronization acquisition comparatively simply when a demodulation station demodulates a signal from a modulation station and to attain the signal demodulation by sending a code series from the demodulation station to the modulation station, using the code series to modulate a data and sending the result from the modulation station to the demodulation station. CONSTITUTION:A code series is generated by a pseudo noise generator PNG and multiplied with a 2nd carrier frequency fB in a 3rd mixer MA and the result is sent from a 1st transmission antenna ANTA1 to a modulation station. A 4th mixer MB1 of the modulation station eliminates the carrier frequency fB from the signal received by an antenna ANTB1 to extract the code series, The extracted code series is superimposed on a data at a 5th mixer MB2 and the result is sent to a 2nd mixer MA2 through a same path as that for data transmission. Then a code series among the code series generated from the generator PNG only through a delay device DL is fed to the mixer MA2 and the synchronization acquisition is realized by adjusting the delay time of the delay device DL to extract the data. |
