We propose fiber-to-the-room deployments as a new centralized infrastructure to distribute Wi-Fi radio nodes and, introduce centralized radio resource control to increase data rates and reduce latency. We define and implement a functional split between lower MAC and upper PHY in the 802.11 protocol stack, where the main fiber-to-the-room unit implements the medium access control protocol for all radio nodes. An optical in-building transport network interconnects subordinate fiber-to-the-room units, which are located in different rooms, implementing only the physical layer and the radio front-end. With a centralized MAC, all stations can be assigned mutually orthogonal time slots, with separate down-link and up-link transmissions. Our evaluation framework starts from detailed building models, using realistic channel models to conduct system-level simulation studies. With a centralized round-robin scheduling approach, our results show a decrease in worst case latencies of up to 84 %, yielding a more deterministic traffic management.

Today's automotive communication systems use baseband pulse modulation and time-division multiple access. Future in-vehicle networks will need to serve a growing number of devices in a multipoint-to-multipoint topology. Therefore, we present a new automotive bus system which allows enhanced channel adaptation and fine-granular multi-user access based on orthogonal frequency division multiple access (OFDMA). We highlight the advantages of OFDMA in automotive applications and sketch the concept. In this paper, we deliver a proof-of-concept for the OFDMA-based automotive communication bus by using an experimental real-time FPGA prototype.

We presentHy-Fi, a system that aggregates light fidelity (LiFi) and radio frequency (RF)-based communication on the 802.11 (WiFi) physical layer by utilizing the MIMO capabilities in IEEE 802.11-compliant commodity WiFi chips.Hy-Fiis based on two key ideas. First, we use inexpensive commodity hardware to facilitate direct transmission of WiFi waveforms over the optical wireless channel, as this is proposed in the IEEE P802.11bb task group. Second, we use the MIMO signal processing from WiFi to aggregate LiFi and radio signals directly at the physical layer.Hy-Fiwas implemented as a prototype and evaluated in a small testbed. Experimental results reveal that our approach offers excellent robustness against signal fading, blockage and external interference in both, the optical and radio channels making it suitable for applications with very strict requirements to the packet delay and loss ratio. Moreover, the two channels, LiFi and RF, can be aggregated to double the link capacity in the best case. Finally, we demonstrate howHy-Ficould be used as wireless access technology in next-generation indoor enterprise networks providing both high capacity and seamless mobility.

We present Hy-Fi, a system which combines light fidelity (LiFi) and radio based on the WiFi physical layer waveform by using the MIMO features available in IEEE 802.11-compliant commodity chip sets. Hy-Fi is based on two key ideas. First, we use inexpensive COTS hardware to facilitate direct transmission of WiFi waveforms over the optical wireless channel, as this is proposed in the IEEE P802.11bb task group. Second, we use the MIMO signal processing to aggregate LiFi and radio signals at the physical layer. The system was implemented as a prototype and evaluated in a small testbed. Experimental results show that our approach offers robustness against signal blockage (Shadowing) and external interference in both, the optical and RF channels. Moreover, the two media (LiFi and WiFi) can be aggregated to double the capacity in the best case.

We assess the performance of two distinct functional splits based on latency/latency variation and mapping efficiency, both individually and in unison. By considering hardware-offloading possibilities for a low-layer split (especially a pre-resource mapper split) using an option-6 software-based local thermal equilibrium split as an example, we show how data rate, Ethernet frame size and, in general, traffic generation characteristics will be very important aspects in the design of the future Ethernet mapping function. Then, an integrated Ethernet fronthaul with legacy and new/evolved split functionality operating at 100 Gb/s link rate is presented with the state-of-the art sub-100-ns latency variation for a timing-protocol flow. This is achieved through the application of a gap-filling aggregator, used for the first time in such a mobile fronthaul application.