| 摘要 |
PROBLEM TO BE SOLVED: To reduce the cost of signal transmission between the base station and a dispersed station facility located around the base station. SOLUTION: A high-frequency signal with a first frequency band transmitted from a base station or a cable MODEM 101 is converted into a high-speed digital signal through an optical conversion unit 301 and connected to an optical cable 132a in a down direction. The optical signal is converted into a high-speed digital signal through a station dispersing unit 400a connected at intervals along the optical cable, branched, and converted into the original high-frequency signal with the first frequency band. Then, the signal is converted into a signal with a second frequency band about 70 MHz, and the desired signal is passed through a band pass filter 407a, converted into wireless frequency band of 2.4 GHz or 26 GHz through an up-converter 406b, further amplified, branched, radiated into a space through an antenna 32, and received by a mobile information terminal 204. The transmission signal in the up direction is transmitted in the reverse transmission path. |
