Patent ID: 7369488

Claim:
A wireless LAN apparatus comprising: as a transmitting-side configuration thereof, a packet length controlling unit, the packet length controlling unit controlling a packet length of transmit data; a packet synthesizing unit, the packet synthesizing unit synthesizing the number of the transmit data corresponding to the packet length controlled by the packet length controlling unit into a packet transmit data and outputting the transmit packet data; a frame synthesizing unit, the frame synthesizing unit appending the packet-length information to a header information of the transmit packet data synthesized by the packet synthesizing unit and outputting the transmit packet data as a transmit frame; and a wireless transmit unit, the wireless transmit unit transmitting transmit frame output by the frame synthesizing unit, wherein the wireless LAN apparatus further comprises: as a receiving-side configuration thereof, a wireless receive unit, the wireless receive unit receiving the transmit frame transmitted wirelessly by another wireless LAN apparatus configured likewise; and an error detecting unit, the error detecting unit judging whether transmit frame is normally received, wherein as the receiving-side configuration of the apparatus, the wireless transmit unit wirelessly transmits a receive data indicating the judgment result with respect to the wireless receive unit to the another wireless LAN apparatus, and the wireless LAN apparatus further comprises, as the transmitting-side configuration thereof, a retransmit controlling unit, the retransmit controlling unit requesting the wireless transmit unit to retransmit the same transmit frame when it is judged that an transmission error occurred from the receive data, wherein as the transmitting-side configuration of the apparatus, the packet length controlling unit further comprises: a retransmit counting device, the retransmit counting device counting the number of the requests for retransmission from the retransmit controlling unit; a retransmit-count upper limit register, the retransmit-count upper limit register setting a count upper-limit value of the retransmit counting device; and a retransmit-packet length controlling device maintaining a value of the packet-length information when the number of the retransmission requests counted by the retransmit counting device is smaller than the count upper-limit value set by the retransmit-count upper limit register and decreasing the value of the packet-length information and when the number of the retransmission requests counted by the retransmit counting device agrees with the count upper-limit value set by the retransmit-count upper limit register.