| 摘要 |
A radio communication system has several communication groups each including a master station and at least one slave station. The communication groups are designated to use a single common frequency. The master station has circuitry for sensing a carrier wave of said common frequency. The master station transmits data when the master station does not detect the carrier wave for a first predetermined time period, and the slave station transmits an acknowledging signal, upon a reception of the data, within a second predetermined time period shorter than the first predetermined time period. The invention avoids signal collision. |
