Towards a Tractable Delay Analysis in Ultradense Networks

Meeting the diverse delay requirements of emerging wireless applications is one of the most critical goals for the design of ultradense networks. Though the delay of point-to-point communications has been well investigated using classical queueing theory, the delay of multi-point to multi-point communications, such as in ultradense networks, has not been explored in depth. The main technical difficulty lies in the interacting queues problem, in which the service rate is coupled with the statuses of other queues. In this article, we elaborate on the main challenges in the delay analysis in ultradense networks. Several promising approaches, such as introducing the dominant system and the simplified system, to bypass these difficulties are proposed and summarized to provide useful guidance. Yi Zhong is with Huazhong University of Science and Technology, Wuhan, P. R. China (e-mail: [email protected]). Martin Haenggi is with University of Notre Dame, Notre Dame 46556, USA (email: [email protected]). Fu-Chun Zheng is with Harbin Institute of Technology, Shenzhen, China and the University of York, York, UK (Email: [email protected]). Wenyi Zhang is with University of Science and Technology of China, Hefei 230027, China (e-mail: [email protected]). Tony Q.S. Quek is with Singapore University of Technology and Design, Singapore (e-mail: [email protected]). Weili Nie was with the National Mobile Communications Research Laboratory, Southeast University, Nanjing, China, and is now with the Department of Electrical and Computer Engineering, Rice University, Houston, TX, USA (e-mail: [email protected]).