Patent ID: 7561582

Claim:
A data reception device for receiving a data packet containing a plurality of packets, each packet of the plurality of packets having first time information added thereto, and the first time information regarding a time at which the plurality of packets are generated, the data reception device comprising: a receive data buffer unit for storing the plurality of packets contained in the data packet; a receive data amount measuring unit for measuring an amount of data stored in the receive data buffer unit to obtain a measured value; a variable clock generation unit for generating a clock having a variable frequency; a time information output unit for outputting second time information that is counted in accordance with a frequency of the clock generated by the variable clock generation unit; and a first time information comparison unit for comparing the first time information added to the plurality of packets with the second time information outputted from the time information output unit, the second time information indicating a time that is behind by a predetermined offset time, and for controlling a timing of outputting the plurality of the packets stored in the receive data buffer unit, wherein the receive data amount measuring unit controls the frequency of the clock generated by the variable clock generation unit in accordance with the measured value obtained by the receive data amount measuring unit, and wherein the time information output unit comprises: a timer unit for outputting third time information that is counted in accordance with the frequency of the clock generated by the variable clock generation unit; a time information extraction unit for extracting the first time information added to the plurality of packets stored in the receive data buffer unit; an initialization unit for coinciding the third time information outputted by the timer unit with the first time information extracted by the time information extraction unit; and an offset unit for delaying, by the predetermined offset time, the third time information output by the time unit to obtain the second time information and for outputting the second time information.