Modulation Techniques and Medium Access Control Protocols for Wireless Access to ATM
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
This report covers modulation techniques and medium access control protocols for wireless ATM.Important aspects of the wave propagation, path loss and time dispersion, are discussed in conjunctionwith the Orthogonal Frequency Division Multiplex (FDM) transmission scheme. In OFDM correct detec-tion relies heavily on the orthogonality of the carriers. When this constraint is met classical modulationmethods as M-PSK and M-QAM can be used. Wireless ATM requires a considerable amount of bandwidth.The frequency reuse factor is made small by using building walls as isolation between clusters. Trafficmodels suited to model arrival processes at ATM-multiplexers are developed to use with system perfor-mance analysis in the multiuser environment. Multiplexer buffer size requirements are found to be higherwith bursty sources. ATM switching is based on multiplexing of small data units or cells. When developingmethods to interconnect mobile units with wired ATM networks this property should be considered. In thiswork a medium access control protocol using dynamic capacity allocation and time division multiplex (TDM) is introduced, Dynamic Capacity Allocation / WireLess Network MAC (DCA/WLNMAC). The pro-tocol supports error free packet delivery and automatic source rate adaption. It is shown that the packetloss ratio easily can be made small by choosing the correct adaptation rate.
Place, publisher, year, edition, pages
1999. , 75 p.
IdentifiersURN: urn:nbn:se:kth:diva-99135OAI: oai:DiVA.org:kth-99135DiVA: diva2:541089
Bernhard, U.Meierhofer, J.
Maguire Jr., Gerald Q., Professor