Communication system including a base station and terminal devices each using an up-link line allocated by the base station

摘要

A communication system allocates a discrete line between a base station and each terminal device that allows discrete communication in a time span equivalent to several frames. The communication system includes a base station that has a processing function unit processing a physical layer using a given data format, and terminal devices each using an up-link line allocated by the base station. In the system, the base station and each terminal device communicates with each other by the orthogonal frequency division multiplexing method. The base station sends out a preamble signal cyclically, and has a means that sends out a vacant discrete connection identifier for identifying a vacant up-link line for a terminal device to send data to the base station when the base station receives an up-link line request from the terminal device.