Performance analysis of wireless heterogeneous networks with pushing and caching

Pushing and caching the popular multimedia data is a promising way to unleash the ultimate potential of wireless networks. In this paper, we contribute to proposing and analyzing the push-based and cache-based content delivery in a three-tier heterogeneous network, where base stations, relays and device-to-device (D2D) pairs are included. We propose to proactively push the popular contents to the relays and parts of the users with caching ability via broadcasting when the network is off-peak. The cached contents can be reused for frequent access to offload the cellular network traffic. The node locations are first modeled as mutually independent Poisson Point Processes (PPPs) and the corresponding content access protocol is developed. The average ergodic rates in the downlink are then analyzed theoretically. We further derive the global throughput gain and the impact of network characteristics on the system performance is illustrated. Simulation results show that the proposed system has significant performance gain, especially for the high density network.