A Two-Stage Content Pushing Service Based on Virtual MIMO in LTE-V Networks

Prefetching based caching technology has attracted much attention owing to its potential for achieving more effective transmission and lower latency. In this paper, we propose to take advantage of prefetching based caching technology in long term evolution based vehicle (LTE-V) networks to actively push content items to vehicle user equipments (VUEs), which are labeled as new vehicle user equipments (NVEs) and old vehicle user equipments (OVEs) based on whether there exist any prior records or not. Meanwhile, roadside unit (RSU) can provide information pushing service, which consists of a user recognition stage and a content pushing stage. Specifically, by grouping vehicles into cooperative coalitions, a virtual multiple-input-multiple-output (MIMO) system can be formed to increase data rate. To maximize the average data rate of users, we propose an Average Channel Gain based Pushing (ACGP) scheme, which selects suitable cooperative partners for NVEs. Numerical results corroborate the analysis and demonstrate the performance of the proposed strategy.