Dead spot or defect in the car? This question will probable occur more frequently in future, with increasing numbers of vehicle functions depending on a reliable wireless connection and constant availability of IT backend systems. IAV has test benches and the necessary know-how to validate new services and track down problems.
Until recently, vehicles were self-contained systems that were not constantly linked to their surroundings. But in future, consumers will demand connected cars that allow access to digital services while on the move. Furthermore, the E-Call emergency system prescribed by law also depends on a stable connection to the cellular network. Connection quality is crucial for all wireless services. High availability must be accompanied by high data rates for streaming music or videos, together with low latency, i.e. responding with imperceptible delays.
New measuring systems for new services
In future, such new services will become an important distinguishing feature for car manufacturers. What's more, consumers are accustomed to using these services with their smartphones, and they are not likely to accept lower standards of quality or availability. This has implications for vehicle development. ”Besides internal vehicle data buses, future developments will also have to consider the wireless channel“, says Dr. Alexander Roy, Senior Technical Consultant for Mobility at IAV. ”But without new measuring systems we would be completely blind. IAV has therefore set up new test benches so that we can investigate the radio channel and IT backend systems.“
It is thus possible to answer some of the questions increasingly confronting development engineers, dealerships and repair shops: Why is a certain service not available in the vehicle? Is it because of a defect or is there no connection to the outside world? And if the latter, at what point does the problem occur – during data transmission or possibly already in the backend system that is supposed to be providing the service? ”Questions like these arise during development and validation but also later on in service“, says Dr. Frank Klinkenberg, head of the Telematics department at IAV. ”The consumers contact the OEM hotlines to report such problems and have them rectified. Our measuring system comes in here too: It helps us find out whether there was a problem with the data service or whether a poor local radio connection was responsible.“
Simulating cellular networks with up to eight base stations
IAV's experts test the quality of cellular connections with a new end-to-end (E2E) test bench which can simulate a cellular network in the laboratory with up to eight base stations, including disturbances, shadowing effects, handover between the base stations, weather conditions and high-speed situations. What is really special is that the real status of cellular transmission channels can be recorded in the field and emulated using live data services after processing in the lab. This kind of ”virtual drive test“ technology can be used for testing new services such as E-Call or streaming radio under reproducible conditions without needing expensive road tests in numerous countries. ”We are currently setting up an acceptance run library for digital services that can be used for testing hardware and software, particularly in adverse environments“, reports Roy. ”This is not a simple task because it demands a wealth of experience – but it also prevents any unpleasant surprises later on.“
At the moment, the team is busy among others with testing the ERA-GLONASS service, which is the Russian equivalent to Europe's E-Call. Besides reception and emulation systems for GPS, IAV also has the corresponding technology for the Russian satellite navigation system GLONASS. ”We have taken on the complete validation scope for an OEM“, says Klinkenberg. ”When problems occur, we can go to the real surroundings and record the cellular environment in order to carry out further tests later on.“
Automated tests of service quality
Together with cellular connection quality, IAV can also test the digital services on the functional level. In particular, this checks compliance with the specific service level agreements (SLAs), such as the availability of a certain service. IAV has set up its own servers for calling up the services both during development and subsequently in regular operation, to monitor the backend systems of the providers. On request, OEMs can access problem reports via a web interface. Besides purely functional testing, the focus can also be extended to the radio channel between vehicle and backend system.
The new lab equipment has been in operation at IAV since mid-2015, and the company's experts are currently forging ahead with further automation of the tests. For example, in future, the OEMs are to have remote access to the results. The new technical possibilities do more than benefitting the development process. In future, they will also help to improve the service provided by manufacturers. The measurement results will also enable their hotlines to make substantiated statements and inform the consumers whether the problem comes from a technical defect or just a dead spot.