| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a radio communications system and the like capable of effectively utilizing resources, assigned to information channels and control channels in radio communications of an orthogonal frequency division multiplexing (OFDM) scheme. <P>SOLUTION: A radio transmitter 200, used in a radio communications system based on an OFDM scheme, includes a determination unit 216 configured to determine the spread factor and the amplitude to be set to a control channel, based on transmission signal quality information and an interference amount from information data; a multiplexing unit 212, configured to multiplex an information channel with the control channel having been code-spread, based on the determined spread factor and amplitude, and means 214 configured to modulate the multiplexed signal in the OFDM scheme and transmit the modulated signal by radio. A radio receiver, used in the present system, comprises a means configured to extract the control channel, by demodulating a received signal in the OFDM scheme and despreading the demodulated signal. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
