Analysis of Stability of PI Queue Management in Ad hoc Network
Weimin Hu · Journal of Anqing Teachers College · 2007
The stability of PI algorithm in active queue management(AQM) is important for the congestion control.Now,PI-AQM design lacks the theoretical analysis of stability mostly based on experience.This paper uses Taylor series expansion to linearize the delay system and analyzes the stability characterization of PI-AQM in wireless Ad hoc network because of large-delay.Finally,we give the stability condition of PI controllers in Ad hoc network.So the design of PI controllers can be improved.By using Matlab and NS2 simulations,the result proves that PI controllers with kp=0.01,ki=0.04 can steady TCP/AQM delay system well.Compared with traditional drop-tail algorithm,PI controller has gotten better control effect for the queue length keeps its ideal value nearby.