Video transmission for multi-hop networks using IEEE 802.11 FHSS

In many applications, such as construction, manufacturing, ground robotic vehicles, and rescue operations, there are many issues that necessitate the capability of transmitting digital video and that such transmissions should be performed wirelessly and in an ad-hoc manner. Recently, we proposed an ad-hoc, cluster-based, multi-hop network architecture for video communications (see Gharavi, H. and Ban, K., 3G Wireless Conference, 2002). For implementation, the IEEE 802.11 FHSS wireless LAN system using 2GFSK modulation was employed. To enhance the overall throughput rate for higher quality video communications, we present a performance evaluation of the IEEE 802.11 FHSS when 4GFSK modulation option is selected. Unfortunately, the 2 Mb/s system utilizing 4GFSK modulation is not very efficient in terms of RF range. Therefore, to improve its performance for multi-hop applications, a combination of diversity and non-coherent Viterbi based receiver is considered. For the video transmission part, we have considered a bitstream. splitting technique together with a packet-based error protection strategy to combat packet drops under multipath fading conditions. Finally, the paper presents simulation results, including the effects of receiver design and diversity on the quality of the received video signals.