Patent ID: 8817613

Claim:
A radio communication system comprising: a radio transmission device having an adaptive modulation function for changing a radio transmission capacity due to quality variations of radio transmission lines; and a MAC frame transmission device for determining and controlling communication quality, wherein the MAC frame transmission device detects a current radio transmission capacity from a PAUSE frame forwarded from the radio transmission device, selects QoS setting suited to the radio transmission capacity from among a plurality of QoS settings which are set in advance, and controls transmission of a LAN signal to the radio transmission device from a user network based on the selected QoS setting, thus forwarding the LAN signal to the radio transmission device, and wherein the radio transmission device determines a modulation method by which data is to be modulated for wireless transmission based on a reception power of a reception signal transmitted from a radio station, multiplexes the PAUSE frame with the modulation method, and outputs the PAUSE frame to the MAC frame transmission device while modulating the LAN signal forwarded from the MAC frame transmission device based on the modulation method, thus wirelessly transmitting the LAN signal to the radio station.