Interoperability between different wireless LAN systems

摘要

A high-throughput (HT) wireless LAN system capable of avoiding a collision of packets and maintaining the original transmission speed is provided. A transmitter is applied to an HT terminal (HTAP) using a second frequency band wider than a first frequency band used by a legacy terminal (legacy AP), in which an HT sequence is started after a legacy beacon as an occupation signal and a legacy CTS are transmitted using every frequency in the second frequency band. Due to this, an NAV is set at the legacy terminal and packets are no longer transmitted from the legacy terminal. As a result, a collision of packets is avoided and it becomes possible to perform communication between HT terminals at the original transmission speed.