Wireless networks provide communications to fixed, portable and mobile users and offer substantial flexibility to both end-users and service providers. Current cellular/PCS networks do not offer cost effective high data rate services for applications, such as, telematics, traffic surveillance and rescue operations. This research studies the feasibility and behavior of outdoor implementation of low-cost wireless LANs used for high mobility telematics and traffic surveillance. A multi-hop experimental wireless data network is designed and tested for this purpose. Outdoor field measurements show the wireless coverage and throughput patterns for static and mobile users. The results suggest that multi-hop wireless LANs can be used for high mobility applications if some protocols are improved.