| 摘要 |
PROBLEM TO BE SOLVED: To make a communication line into time division multiple access and to improve channel efficiency by performing spread spectrum modulation based on a spread code, making signals into time division multiple access, arranging them in a time slot and transmitting them. SOLUTION: A central controller 240 stores the selected time slot on a highway 260 in a time slot memory 215-2 inside a buffer memory 215 in a No.1 modem 210 through a signal reception distribution device 230. Thereafter, a time switch slot 215-1 is closed, the information of 8 bits which enters a shift register 215-3 is immediately transferred to the shift register 215-4 and the shift register 215-3 prepares for the reception of the signals of the next frame. Data and a control bit are added after the transferred information of 8 bits and they are sent to the spread modulator 211 of the No.1 modem 210, spread spectrum modulated by an outgoing PN code supplied to a #m1 terminal equipment, amplified and then, transmitted from an antenna 500. |
