上游充通大￥ SHANGHAI JIAO TONG UNIVERSITY Fundamental Relationship between Node Density and Delay in Wireless Ad Hoc Networks with Unreliable Links Shizhen Zhao,Luoyi Fu,Xinbing Wang Department of Electronic Engineering Shanghai Jiao Tong University,China Qian Zhang Department of Computer Scien Engineering Hong Kong,ChinaFundamental Relationship between Node Density and Delay in Wireless Ad Hoc Networks with Unreliable Links Shizhen Zhao, Luoyi Fu, Xinbing Wang Department of Electronic Engineering Shanghai Jiao Tong University, China Qian Zhang Department of Computer Scien Engineering Hong Kong, China