| 摘要 |
PURPOSE: A remote base station system is provided to prevent generation of mutual interference between channels by transmitting a plurality of subscriber signals as baseband signals of a low frequency between a main base station and a remote base station. CONSTITUTION: A modem unit(210) outputs baseband signals of a plurality of subscribers to each allocated frequency channel. A main signal unit(220) up-converts baseband signals into RF signals and combines them to make an analog signal, amplifies it by pre-set level of power, and outputs it to an antenna(260). A main controller(290) outputs a signal for controlling a remote base station(500). A multiplexer(310) multiplexes the digital control signal of the remote base station(500) and baseband digital signals of a plurality of subscribers and outputs it. A serial converter(320) converts a signal outputted in parallel from the multiplexer(310) to a serial signal, adds a system clock thereto, and outputs it. An E/O(Electrical to Optical converter)(330) converts an electrical signal applied from the serial converter(320) to an optical signal and outputs it to an optical cable(400). A GPS(Global Position System)(270) receives a 10MHz reference clock signal from a GPS. A PLL(Phase Locked Loop)(280) receives the 10MHz reference clock signal, generates a 30.72MHz system clock and applies it to each function part of a main base station(200). |
