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This paper investigates how the performance and capacity of the IEEE 802.11 medium access control (MAC) layer is affected by pulse jamming, using a time-driven simulation program in C language implemented at the Communications Laboratory of the Helsinki University of Technology. The simulations demonstrate the effect of pulse duration and pulse repetition interval on the IEEE 802.11 wireless local area network (WLAN) capacity, defined in terms of simultaneous Voice over IP (VoIP) connections. Under normal conditions (i.e., no jamming), the WLAN can support a certain number of real-time VoIP connections, taking into account the fact that VoIP traffic cannot tolerate excessive delays caused by multiple retransmissions or the build-up of VoIP packets in the transmission buffers of the wireless stations. The simulations show that during severe pulse jamming, the number of supported VoIP connections is substantially decreased.

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In this paper, the performance of a Mobile Ad-hoc Network (MANET) is studied in a military environment. Link level simulations are based on the IEEE 802.11b standard and mobility is modelled using the random waypoint model. The military environment consists of jamming and vegetation. Jamming sources are Unattended Jammer (UAJ) and Unmanned Aerial Vehicle (UA V). The results show that both of the jammers can considerably debitilate the network connectivity.