Research On Random Access Technology Of Data Link Based On SDN

In the modern information war and complex electromagnetic environment,the data link network needs to have anti-interference ability to avoid the unreliable communication system caused by interference or malicious attacks.Because the combat platform moves rapidly,it often switches back and forth in multiple networks according to specific business needs and surrounding electromagnetic environment.Due to the expansion of the battlefield,many mobile terminals need to share information and work together to improve the overall operational capability.However,the traditional data link network cannot switch frequency timely according to the surrounding environment and the terminal is difficult to adaptively select appropriate data link network.In addition,different data link network have different processing ability and MAC protocols,so it is difficult for combat platforms to connect with each other.Software defined network technology separates control function from the traditional network equipment,and covers differences of underlying network(such as equipment specifications,system,network transmission protocol,etc.).At the same time,it simplifies interoperability between heterogeneous networks.Therefore,the software defined network technology provides timely and comprehensive information which is convenient for the console to assign tasks and resources reasonably.Besides,cognitive radio technology can detect and identify the surrounding environment to get some information about the available data link network.Then,the node can dynamic access to the network and choose the best frequency for data transmission.From what has been discussed above,the cognitive radio technology can solve the problems caused by mobile terminals and channel interference,improving the stability of communication system.This paper analyzes the military requirements of modern information war and the shortages of traditional data link network.Moreover,we propose Random Access Technology of Data Link based on SDN according to the software defined network technology and cognitive radio technology.Then,the main research contents are as follows.First,we design a unified architecture for different networks based on SDN,which can reduce the complexity of communication between heterogeneous networks and improve the coordination ability of the whole combat system.Second,we propose spectrum sensing strategy and channel management mechanism,which can get spectrum resources in the surrounding environment and choose the best frequency for data transmission.As a result,it solves the problems caused by channel switching effectively and improves the anti-interference ability of the network.Third,we proposed random access technology.Thus,the node can quickly join or leave the network to ensure the timeliness and reliability of data transmission according to the specific task and surrounding environment.In the end,we use the OPNET to simulate TDMA and polling network scenarios and design parameters.After that,we demonstrate the feasibility of the scheme by comparing the theoretical analysis and simulation results.