Base-Station Assisted Device-to-Device Communications for High-Throughput Wireless Video Networks

TL;DR

This paper introduces a scheme that leverages user device caching and device-to-device communication to significantly boost wireless video network throughput, reducing reliance on central infrastructure.

Contribution

It presents a novel approach combining caching and D2D communication, with analysis of optimal collaboration distance and spectral efficiency gains.

Findings

Spectral efficiency can improve by 10 to 100 times.

Random caching performs nearly as well as optimal caching.

Significant throughput gains are achievable even with low request redundancy.

Abstract

We propose a new scheme for increasing the throughput of video files in cellular communications systems. This scheme exploits (i) the redundancy of user requests as well as (ii) the considerable storage capacity of smartphones and tablets. Users cache popular video files and - after receiving requests from other users - serve these requests via device-to-device localized transmissions. The file placement is optimal when a central control knows a priori the locations of wireless devices when file requests occur. However, even a purely random caching scheme shows only a minor performance loss compared to such a genie-aided scheme. We then analyze the optimal collaboration distance, trading off frequency reuse with the probability of finding a requested file within the collaboration distance. We show that an improvement of spectral efficiency of one to two orders of magnitude is possible, even if there is not very high redundancy in video requests.