Patent ID: 7894366

Claim:
A wireless communication apparatus which performs a wireless communication for streaming data by using one of a plurality of switchable communication rates depending on a radio signal propagation condition, comprising: a memory unit to store a data table including corresponding information about each of the communication rates within the wireless communication apparatus and a maximum data transfer rate of streaming data, the maximum data transfer rate having a transfer quality that is ensured by each of the communication rates; a communication state control unit to control optimization of a data transfer efficiency based on the radio signal propagation condition, while ensuring the transfer quality, comprising: a quality assurance level specifying unit to search the data table stored in the memory unit by using a specified target data transfer rate of the streaming data to be transmitted as an index key, to select one or more of the communication rates that ensure the transfer quality of the specified target transfer rate, and to specify a quality assurance level of the communication rate that is a lowest communication rate among the selected one or more communication rates; a communication rate setting control unit to perform a test wireless communication in which test streaming data having a same data transfer rate as the specified target data transfer rate is transmitted at each of the one or more communication rates on a step change basis from the quality assurance level to a maximum communication rate available in the wireless communication apparatus unless a communication error is detected within a predetermined fixed period of time, the communication rate setting control unit to determine a one step lower communication rate as an initial value of the communication rate when the communication error is detected, the communication rate setting control unit is to determine the maximum communication rate as the initial value of the communication rate when no communication error is detected during the test wireless communication, the communication rate setting control unit is to set the communication rate to the initial value when the wireless communication is started for the streaming data, and is to change a setting of the communication rate according to the radio signal propagation condition during the wireless communication by keeping the quality assurance level as the minimum communication rate; and a transmission process unit to perform a modulation process of the streaming data according to the communication rate that is set by the communication state control unit and to transmit the modulated streaming data.