PURPOSE: To improve the operating efficiency, by inserting and extracting a small capacity data signal to a large capacity long range line in each area so as to provide the function of a small capacity digital line to the large capacity line and the conventionality.
CONSTITUTION: A carrier signal from a transmission station oscillator 11 enters a π/2 phase modulator 12, where it is π/2 phase-modulated with a data signal having a small capacity sub-code transmission speed f2 from a terminal 13. Further, the signal enters a π phase modulator 14, where it is π phase-modulated with a large capacity main data signal having a code transmission speed f1 from a terminal 15 and transmitted to a terminal 16. The relation between the f1 and f2 is assumed as f1>f2, the carrier signal is π phase-modulated with the large capacity main data signal (f1), and a sub-data signal (f2, small capacity data signal) applies π/2 phase modulation. In the vector arrangement, the π phase is changed between A1 and A2, or between B1 and B2 in the speed of f1, and the π/2 phase is changed in the speed of f2 between A1 and B1 or between A2 and B2.
| JPS5269506 | SECONDARY CARRIER WAVE PILING PCM-IM COMMUNICATION SYSTEM |
| JPS57171869 | MODULATING SYSTEM |
| JPH02196547 | CONTROL SIGNAL TRANSMISSION SYSTEM |
TAGASHIRA YOSHIMI
YAMAZAKI FUMIAKI
MUKAI TADASHI
NIPPON TELEGRAPH & TELEPHONE
| JP46009966A |