NCTUNs tool for IEEE 802.16J mobile WiMAX relay network simulations

An IEEE 802.16j mobile WiMAX relay network is a next-generation mobile wireless broadband network. Compared with IEEE 802.16e, which also supports mobility, IEEE 802.16j introduces relay stations to the network to help relay packets between the base station and a mobile station. When a mobile station is shadowed by a building and thus has a badquality channel to the base station, such a relay design can help it achieve a higher throughput from/to the base station. Since IEEE 802.16j is a new standard and no such products are available yet in the market for researchers to evaluate its performances, developing a network simulator that supports IEEE 802.16j network simulations is very valuable. In this chapter, we present how we extend NCTUns, a network simulator and emulator that directly uses real-life TCP/IP protocol stack and applications to generate accurate simulation results, to support IEEE 802.16j network simulations. NCTUns supports the two relay modes defined in IEEE 802.16j: the transparent mode and non-transparent mode. More information about NCTUns is available at http://NSL.csie.nctu.edu.tw/nctuns.html.