A performance evaluation on the use of IEEE 802.11 for long range communication

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Wireless equipment based on the IEEE 802.11 standard have enjoyed widespread success during recent years. Traditionally, such equipment have mainly been used indoors to allow users to wirelessly connect to the Internet or a LAN. By using directional antennas the range of 802.11 equipment can be extended to reach several kilometers outdoors, expanding the areas of usage and applications for the 802.11 standard. This thesis evaluates of the shelf equipment based on 802.11 in a variety of situations, including both stationary and mobility tests. Performance tests of distances of up to 2000 meters have been possible to perform by connecting directional antennas to standard access points. Furthermore, a number of different transport layer protocols have been tested in order to cover a broad spectrum of the various types of applications that can come into consideration. Knowledge of distance limitations for this type of equipment and the performance impact of different transport layer protocols is of interest for the missile test range, RFN, in order to see if it is possible to use standard off the shelf equipment for some tasks during test activities.The results of the stationary tests show that the access points used in this thesis perform very well up to the maximum distance tested (2000 meters). Of the four TCP variants tested TCP Vegas is the overall winner, combining high throughput with noticeably fewer frames retransmitted by the access points. For UDP, few packet losses and low jitter were seen in general. As for the mobility tests, speeds of up to 100kph, although leading to mo...