Precise Positioning Solution Put to Endurance Test

Work where others go on vacation. A very special form of this workation slogan took our experts Alexander and Pascal right across Europe this week. Their plan was to demonstrate live how precisely the position of a vehicle can be determined using our Precise Positioning technology. An important prerequisite for, inter alia, autonomous driving, the name says exactly what it claims to accomplish. Read the blog and follow day by day how their adventure progressed.

PS: Read in the Infobox (below) how the solution works, what advantages it offers and which industries and applications benefit from them.

Table of Contents

• Prolog: Preparation
• Day 1: Hannover – Kreuzlingen
• Day 2: Kreuzlingen – Chamonix
• Day 3: Chamonix – Port Vendres
• Day 4: Port Vendres – Barcelona
• Our Key Takeaways

by Pascal Lambert and Alexander Wolle

We owe the idea for this tour of Europe to Swift Navigation, Telkekom’s Precise Positioning technology partner. San Francisco-based Swift provides its Skylark cloud service, which supplies the correction data for satellite navigation. In 2019 Swift drove a test vehicle from San Francisco to New York to put Precise Positioning to the test in everyday conditions. And that is exactly what we were now doing in Europe.

To do so we joined forces with the Deutsche Telekom Group Partnering & Devices (GPD) and Deutsche Funkturm (DFMG) teams, borrowed a stylish station wagon from our Telekom Mobility Solutions colleagues and packed it full to the brim with technology.

Here is some of what we had on board:

• An LTE antenna and two GNSS antennas
• A Dual-SIM LTE router with failover switching and a T-Mobile and a T-IoT SIM card to connect with the Skylark Cloud server
• Various boards, evaluation kits and a reference system with GNSS chips
• A GNSS simulation and test system in order to run the test drive as often as needed in the lab and to use the data for recent soft- and hardware versions and for error analysis
• Coffee and filled bread rolls

And this is our route: Hannover – Kreuzlingen – Milan – Chamonix – Port Vendres – Valence – Badalona – Barcelona

Set out from Hannover in the morning with around 680 kilometers ahead of us to Kreuzlingen, the largest Swiss city on Lake Constance. On this first day of the tour our initial task is to put miles on the clock because Precise Positioning obviously works very well in Germany. That’s not just where most of our reference stations are (see Infobox) but also, for example, more than 80,000 cellphone antennas that can provide 80 million people (95 percent of the population) with 5G.

We first take a closer look at our monitors and the measurement data as we cross the border into Switzerland. The purpose of this test is to check how reliable the Precise Positioning service is when a vehicle switches to another country’s cellphone network. And lo and behold: the handover from the German to the Swiss network runs smoothly thanks to our global roaming agreements. First mission accomplished, time to call it a day.

Except for minor tailbacks there were no traffic jams on Day One, so in Kreuzlingen we were able to walk back along the shore of Lake Constance for an evening meal in Germany.

Today’s 570 kilometers will take us through the Alps twice with a detour via Milan to Chamonix in France. Our first stop after a short distance: we need a toll sticker for Switzerland.

The Gotthard road tunnel, nearly 17 kilometers long, is the first test of our system. Here too, however, Precise Positioning delivers the goods. Our station wagon can be located precisely on the monitor.

In the car itself all is not plain sailing. Shortly after leaving the tunnel we notice that our test setup’s power supply has gone AWOL. The GNSS receivers continue to be powered by a backup battery but the GNSS recorder has a backup battery of its own that is already flat. The cigarette lighter’s fuse turns out to be to blame. Replacing it is only a short-term solution. The empty backup batteries’ extremely high charging current is too much for the cigarette lighter’s fuse, which soon blows again. After a rethink we decide to connect the recorder directly to the car battery and to run only the test setup from the cigarette lighter. We also have to replace the test setup’s plug, which was unable to withstand the heat and fused, causing additional resistance. After two hours’ work, blocking three parking spaces and many skeptical looks, we had all systems back up and running and were able to resume our journey.

Taking a late lunch break on Lake Como we rewarded ourselves with a traditional pizza. We watched as seaplanes took off from the harbor and our mood improved. Then it was back to the Alps and the border between Italy and France, which we crossed in the Mont Blanc tunnel, which is nearly 12 kilometers long. After the 1999 fire the tunnel underwent elaborate safety changes. We were issued with written instructions on what to do in the event of unforeseen incidents, speed and distance between vehicles are regulated precisely and indicated by signs, and using the tunnel costs a hefty 52 euros.

On the French side we soon reached our destination Chamonix, altitude 1,000 meters, with a view of Mont Blanc. But it was late by then after the repairs and an hour’s wait to enter the tunnel, so we dined in the hotel.

We made an early start with a view to taking the spectacular cable car to the 3,842-meter Aiguille du Midi on the Mont Blanc plateau. But we were out of luck. With 150 km/h winds blowing up there the cable car was not running that day. It seemed like the Alps just didn’t like us.

So it was off to Port Vendres in France, just short of the Spanish border, with nearly 700 kilometers ahead of us. We switchbacked down to lowland country and France’s customarily fine freeways, taking the Autoroute du Soleil toward the Côte d’Azur. In temperatures of up to 35°C we stopped for a lunch break in Valence: pizza again, which amazingly tasted much better than the previous day’s pizza in Italy.

Technically everything was going smoothly. Neither the high mountains nor the switchbacks nor passing through different cell network zones caused our measurement system the slightest headache. Our station wagon stayed on track both on the road and on the screen. Arriving in Port Vendres on the Mediterranean, we chilled in the hotel’s rooftop pool before heading for the fishing harbor and a harbor festival with live music.

Our final destination Barcelona was in theory only 200 kilometers away but we decided to take the coast road. It is about 40 kilometers longer but takes us through some pretty villages rather than along the dreary autobahn. After a lunch break and a black paella mixta in the harbor of Badalona we reach Barcelona in the late afternoon. There we found that tall downtown buildings had not the slightest negative effect on the Precise Positioning system’s accuracy.

We ended our Precise Positioning tour with a tour of the sights of Barcelona: the Sagrada Familia basilica, still unfinished, the Ramblas with all its storers, bars and attractions, and a fish restaurant serving excellent skate. We spend our last evening in the Sky Bar of our hotel with a view of the brightly illuminated Torre Glories. Tomorrow we drop off the car and, sadly, fly back to Hannover.

• After four days and 2,183 kilometers on the road we had collected 24 terabytes of data to back up.
• Our Precise Positioning test system had no outages.
• We recorded an extremely high level of accuracy with deviations of no more than four to six centimeters.
• Accuracy remained high even when we lost contact with the satellite signal in tunnels.
• And next time we would connect the test setup straight to the battery and not to the car’s cigarette lighter. 😊

What comes next? Various departments will spend the next few weeks assessing, collating, analyzing and evaluating all the data. So it will be a while before we can finally present a detailed technical report, but for the two of us it is already clear that Precise Positioning totally convinced us in its field test on our tour of Europe!