Radio Technology with a Relay Aircraft and GPS Antenna Tracker for the World Run in Olten
It is May 7, 2017. A Piper Seneca V is flying over the Canton of Solothurn in Switzerland at 12:50 p.m. The aircraft originally took off in Germany and is now circling over the city of Olten. In a few minutes, the aircraft is set to receive and transmit high-frequency radio signals. At 1 p.m. on the dot, the fourth “Wings for Life World Run” gets underway in Olten. Around 4,000 runners set off on what is a special run with a mobile finishing line, the so-called “catcher car.” More than 150,000 runners worldwide are taking part in the simultaneous global charity race, which is broadcast live. The company HDwireless from Mechernich, close to Cologne, is getting involved for the fourth time too and is providing the wireless camera transmission as well as taking care of the radio production and transmission of GPS positional information in Olten. Precise planning and radio coordination was necessary during the preparation phase to enable them to provide complete radio transmission over the 80 km-long running course. When it comes to transmissions across such an expansive area, bi-directional radio is operated via a flying relay station. This offers many benefits, such as the continuous and cost-efficient flight for the entire duration of the event without the need for intermediate landings, as well as not being at the mercy of the weather conditions at high altitudes, which enables outstanding transmission quality. The relay aircraft receives video signals from wireless cameras, which camera operators on two motorbikes use to provide live coverage from the course. The signals are processed on board the aircraft and transmitted without interruption via a downlink array to the stationary ground antennas, which are located on top of a 40-meter-high cherry picker. Perfect reception is ensured by an antenna system that is always pointing toward the aircraft. For the first time, HDwireless is launching a recently designed in-house development for the World Run. CEO Patrick Nußbaum explained: “Our new GPS antenna tracker aligns the antennas according to the GPS position of the relay plane, which, in turn, is guided by the GPS information transmitted by the motorbikes. All GPS information from the mobile transmission/receiving stations can be controlled and positioned via our on-site data network, which we also developed ourselves. It is possible to check the GPS positions at any time, as you can view them using Google Earth.” All radio signals are received in the “Wireless Video Village” by the high-frequency ground antennas in the “HDwireless RF1” production car. The antenna signal is fed, decoded and transmitted to the broadcaster’s OB car using fiber-optic cables. The GPS information is read from the data network and used to control the GPS antenna tracker. At the same time, the RF1 is the nerve center of the operation, with its own communications network and transmission cells for the team and radio production. Patrick Nußbaum summed it up as follows: “The HDwireless team is the full-service provider for video, audio and communications nowadays.” After running 68.11 km, the winner is eventually overtaken by the catcher car on the running course in Olten. The run is over and the relay aircraft with the HDwireless high-frequency transmission technology on board returns to Germany to land after having been in the air for six hours.