Science and Development Network (SciDev.Net)
This paper presents the LQ-Servo control with observer for TCP/AQM system considering an input time-delay. This controller structure is made by taking a traditional servo mechanism based on Linear Quadratic approach and by augmenting a new state variable to the feed forward loop. In order to estimate the state of TCP window packet size, the control structure is extended with observer based on Kalman filter. Computer networks have been explosively increased, and have confronted severe congestion collapse problems according to growth of packets.