Base-station assisted device-to-device communications for high-throughput wireless video networks

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.Existing Literature: Exploiting the redundancy of video requests in cellular networks is not new, but in the past has been used in fundamentally different ways compared to our approach.Wireless TV, such as MediaFlow, was exploiting the broadcast effect to supply the same video stream to many users simultaneously. However, consumers expect on demand capability for cellular transmission. Caching of popular files at the base stations, or at mobile switching centers is discussed, e.g., in [3], but it only helps to reduce the strain on the cellular backhaul, without alleviating the "on air" congestion. However, the efficiency of this approach is limited by the number of files that can be stored on a single device. A pioneering precoding scheme that works in conjunction with broadcast from the BS was recently introduced by [4]. Caching files that

Opportunistic Spectrum Utilization in Vehicular Communication Networks

“…2.6. By utilizing the proximity of mobile users and direct data transmission, D2D communications can increase spectral efficiency and throughput, improve overall throughput and performance, improve energy efficiency, and reduce communication delay for mobile users [54]. Due to the advantages of D2D communications technology, it is suitable for many use cases, and can enable novel location-based and peer-to-peer applications and services.…”

QoE-Driven D2D Media Services Distribution Scheme in Cellular Networks

“…This assumption has been widely used [8] to describe content popularity distribution. According to the Zipf distribution, the popularity that a service is requested by a user is given by…”

“…In [8], by means of exploiting the optimal collaboration distance, Golrezaei et al have proposed a novel scheme to increase the throughput of video files, which in the cellular networks proves the possibility of improving spectral efficiency. The new architecture to achieve wireless D2D cache collaboration is proposed in [9] from the viewpoint of asymptotic scaling characteristics and video content popularity.…”

“…In terms of the network provider part, the BS acts as gateway to connect the users to the media service providers. [8][9][10]. In our model, each user that is mobile and always connected to the BS is indicated as ∈ ≡ { 1 , .…”

Device-to-device data storage for mobile cellular systems

“…As the storage capacity of mobile devices increases, data files could be stored and retrieved from the mobile users themselves in order to offload download traffic from the infrastructure network. Distributed storage in Delay Tolerant, Ad Hoc and D2D networks has been suggested in [5], [6], [7]. In these, mobile terminals (with backup connections to an infrastructure network) are used to cache and distribute data files.…”