Research On The Application Of Concatenated Code On WATM Error Control

WATM is regarded as main technique for future wireless communication, for its unique advantage to supply multimedia services. Lately, WATM has been paid more and more importance on. Many colleges and scientific research organizations have investigation and discussion on WATM, no matter they are domestic or overseas. This paper proposed an effective error control technique for WATM header.First, we found the original HEC of ATM can not satisfy the QoS of multimedia service by investigating the original error control scheme in the case of high error bit ratio. So we proposed a new cell formation to solve the problem which is brought about by wireless channel.Second, we proposed a WATM protocol based on the reqirement of WATM. And we anylized and contrasted the error control methods which are suit to WATM.Lastly, A cell structure of wireless ATM based on QoS is proposed. The TDMA/TDD protocol has been adopted at the MAC layer. In each frame, which connection each time-slot corresponds is dynamically allocated by the base station. The base station can detect its corresponding connection by the position of the time-slot. Thus the VCI/VPI transmission can be partly omitted in the wireless channels. Therefore, as many as 16 bits of BCH code are added to the cell head for the error control, which replaces VCI/VPI of the standard ATM cell head. Concatenated code is applied to ATM cell header as an error control solution. This paper analyzed the concatenated code combined BCH code with convolution code and concatenated code combined BCH code with Reed-Solomon(RS) code . These methods can perform effectively in presence of higher error ratio in wireless channel, in the end, the computer simulation shows the performance of this scheme. The result shows this method can satisfy the demands of WATM QoS.