| 摘要 |
The apparatus (36) is for a central station in a multi-direction time division multiplex communication system in which the central station transmits signals assigned to respective satellite stations in a time division multiplex broadcast mode, while each of the satellite stations after extraction of a clock extracts the signal assigned thereto and intermittently transmits signals to the central station after adjusting the signals to such a timing that, when the signals reach the central station, the signals from the various satellite stations do not overlap and appear in order as a single sequence of time division multiplex signals. The received signals demodulated by a demodulator (30) are applied to a plurality of code regenerations (321-32n) receiving different phase clocks from a clock phase delay circuit (46). A phase comparator (40) compares the phases of the central station clock with a clock extracted (44) from the demodulated signal. A sample and hold circuit (42) holds the output of the phase comparator (40) TDM burst by TDM burst and controls a selector (48) which despite any fluctuation of absolute delay time which may occur during communication between the central and satellite stations due to variations in the ambient conditions, the central station selects the output of that particular code regenerator circuit (321-32n) which is operating responsive to a decision clock whose timing matches with the fluctuation, thereby allowing the system as a whole to hold a communication without having the error rate increased. Temporary stores (381-38n) provide delay compensating for the response time of the loop controlling the selector (48). |
