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Abstract
Asynchronous transfer mode CA TM) is considered the most suitable transport technique for the future broad band integrated services digital network (B~ ISDN), due to its ability to flexibly support a wide range of services with quality-of¬service (QoS) guarantees. On the other hand, wireless communications have been developed to a level where offered services can now be extended beyond voice and data. For such, the combination of wireless communications and A TM can provide freedom of mobility with service advantages and QoS guarantees. The main challenge of wireless A TM is to harmonize the ’development of broadband wireless systems with B-ISDN and ATM LANs, and offer similar advanced multimedia multi service . features for the support of time-sensitive voice communications, LAN data traffic, video, and desktop multimedia applications to the wireless user. Several technical issues must be resolved before ATM services can be efficiently extended to the wireless environment. The provisioning of QoS is particularly difficult in the wireless environment due to the scarcity of bandwidth ¬whereas A TM was designed for bandwidth-rich environments, and due to the high and fluctuating bit-error rates (BER) of the radio channel - considering the fact that A TM was designed for media whose bit error rates are very low (about 10-1°\ In this thesis, the ways by which the performance of a wireless A TM link could be improved are tackled by using error control schemes. Variant Forward Error Control schemes are presented and their performance are analysed with regards to the bit error rate and throughput values. The performance of BCH codes, Reed Solomon coded, and Convolution ones are analyzed by remaining the frequency bands and data rates recommended for the W A TM channel model.