Research And Improvement On Greedy Perimeter Stateless Routing Protocol In UAV Network

As the economic development and technology popularization,UAV(unmanned aerial vehicles)become one of the fastest growing industries in civil field in recent years.In the early days,UAVs can only be used in the military field,as air reconnaissance,battlefield observation and war assessment purposes.With the unmanned aerial technology civilian,the UAV has been able to perform aerial photography,agricultural plant protection,disaster monitoring,security detection and other tasks.UAV mission effectiveness has limitations because of not long enough duration,not far enough flying distance and not strong enough RF power.The MANET can improve the control ability of UAVs system,improve the work efficiency and coordination ability of UAVs system,and improve the reliability,stability and survivability of UAVs system.The routing protocol is the key technology of UAV MANET.As GPSR(Greedy Perimeter Stateless Routing)have some characteristic,low routing overhead,strong scalability,adapt to high dynamic topology,making it become the routing protocol best suited for UAV networks.However,GPSR has a lot of room for improvement because of the non-optimal path and the low efficiency of peripheral forwarding,as well as the difference between the simulation environment and the actual environment.This paper proposes a Signal-Strength-Fix Based Greedy Perimeter Stateless Routing(GPSR-SF),which uses propagation models to refine the assumptions of wireless coverage in protocol design.Before transmitting data packets,estimating the signal attenuation to determine whether the signal can cover the next hop.Estimating the signal coverage,find the most optimal next hop in greedy mode,and judge whether or not to switch forwarding mode.GPSR-SF routing protocol is implemented and the simulation environment is built using NS-3 network simulation platform.The performance of GPSR-SF and GPSR under different wireless equipment parameters were compared by simulation.The GPSR-SF routing protocol is proposed,which achieves a lower EED(end-to-end)delay without reducing the PDR(packet delivery rate).