High-speed wireless access device

A high-speed wireless access device comprising:

• a first wireless modem in a base station and a second wireless modem in a mobile terminal,
• wherein said first wireless modem in a base station includes,
• a low-speed modulation means;
• a first high-speed modulation/demodulation means with a first equalizer built-in;
• a low-speed packet adding means for adding a low-speed packet by said low-speed modulation means to the-beginning of a high-speed packet;
• an information adding means for adding information to said low-speed packet in order to inform a terminal to which terminal a packet is transmitted;
• and
• a transmission means for transmitting a packet addressed to a mobile terminal by switching to a high-speed mode immediately after adding said low-speed packet,
• and said second wireless modem in a mobile terminal includes,
• a low-speed demodulation means;
• a second high-speed modulation/demodulation means with a second equalizer built-in;
• a switching means for switching from said low-speed demodulation means to said second high-speed modulation/demodulation means and vice-versa;
• an analyzing means for analyzing data received by said low-speed demodulation means;
• a means for turning off said low-speed demodulation means and for turning on said second high-speed modulation/demodulation means when a packet addressed to said mobile terminal is recognized;
• a means for turning off said second high-speed modulation/demodulation means after receiving said packet addressed to said mobile terminal;
• an AGC information holding means for holding AGC information in a low-speed receiving mode and for making use of said AGC information in a high-speed receiving mode;
• and
• a timing extraction information holding means for holding timing extraction information in said low-speed receiving mode and for making use of said timing information in said high-speed receiving mode.