Reliable Wireless Connectivity for Self-Driving Vehicles Academic Advisers: Robert Piechocki, Angela Doufexi, Andy Nix - PDRA: Andrea Tassi

Design and deployment of a full-stack solution enabling ultra-reliable communications among moving vehicles. Our network scenarios are characterized by: (i) delay-sensitive and safety-critical services, (ii) heterogeneous network topologies and (iii) dense networks. 4G/5G systems are not suitable for those scenarios. Hence, we aim to enhance the IEEE 802.11p/DSRC protocol stack.

Project Aim and Research Challenges  

IEEE 802.11p PHY/MAC on Portable SDRs  

Full-Stack Simulations for Large-Scale Scenarios  

Service Optimization  

We designed a portable testbed composed by SDRs acting as IEEE 802.11p transceivers, in standalone mode (no controlling PCs are required). Measured data are logged onto storage devices connected to the TX/RX.

Communication Systems & Networks© CSN Group 2015

Fig. 1 Main entities of the PHY/MAC testbed.  

Fig. 3 Structure of the full-stack IEEE 802.11p/DSRC simulator and shadowing model.  

Usually, network simulators (ns-3, inetmanet, etc.) refer to simplified PHY layers based on lookup tables. The accuracy of full-stack simulations depends on the accuracy of tabulated data, which is usually the result of computer simulations. By means of our portable SDR testbed, it is possible to derive accurate MAC PDU error rate curves suitable to be integrated into full-stack network simulators. In that way, the simulation accuracy dramatically improves.

The IEEE 802.11p/DSRC stack has got a plethora of parameters to be optimized. •  Considering sensing/radar applications, the service profile and the user QoS

depends, for instance, on the distance to the area where an accident occurred. As a result, closer vehicles need basic information to avoid the collision, while further vehicles have the time to receive much refined data streams and take long term actions.

•  On the other hand, in the case of ultra-dense networks, MAC protocols are crucial to grant to each user (at least) access to safety-critical services.

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TX RXChannel Emulator

Fig. 2 TX block diagram.  

MAC (broadcast only) and PHY (IEEE 802.11p compliant) layers implemented in GNURadio/C++.