Case Study published in the printed edition of “Pure Live 2018”
Live images from wireless cameras are an important part of many broadcast
and event productions. Service providers such as HDwireless are specialized
in such high-frequency video radio transmissions. With the project-specific
“wireless camera solution”, the company from Mechernich near Cologne,
Germany, offers the right technology for every dimension of video radio.
For more extensive projects with wireless cameras, HDwireless has
created its own mobile HF production unit.
“The HDwireless RF1 concept stands for reliability and flexibility in RF video transmission.”
HDwireless RF1 is designed as an interface between wireless camera systems and a broadcaster’s OB van or video control room, for example for event productions. All RF signals converge in the production vehicle. In addition to video images, these signals can include signals for camera control as well as any data or radio signals for on-site communication with the director and team. The technology processes the incoming information and provides camera signals via cable, for example via fibre optics. The RF technician on board has complete control over all signals and processes via RF receivers, displays and RF measurement technology. Short vehicle set-up times allow a high flexibility of use. With the mobile production unit, rapid location changes are very easily possible – as is the case when it comes to sports events, which last several days. All of the vehicle’s technical components are optimised for reliable and fast operation – up to the 12-metre high antenna mast, which is ready for operation within a few minutes. “The selected and compact equipment in the HDwireless RF1 allows the realisation of RF productions with up to 16 wireless camera systems in HD and 4k.”
The air-conditioned vehicle is based on a Mercedes Sprinter and optimised for outside broadcast applications.
It can connect wireless camera systems, RF signal processing/control and RF frequency monitoring with the imaging equipment designed in a consistent 3G-SDI standard and for 4k environments. Monitoring occurs using UHD displays from Sony. The RF structure is equipped with multiple RF distribution units and “RF over fibre” solutions, so that up to 16 wireless camera systems including camera control can be processed in parallel via the signal and process structure. The RF1 offers full camera control for Sony, Ikegami and Grass Valley camera systems. Integrated network, intercom and fibre optic systems enable simple, fast and trouble-free connection to the production environment on site. The high antenna mast is suitable for static antennas and for the HDwireless GPS antenna tracker system, which greatly increases the RF range of antennas for mobile transmitters.
“One HF production vehicle and a lot of camera combinations.”
The requirements for wireless camera transmissions differ considerably. Hence, the pool of RF-capable systems in HD and 4k resolution with Sony, Ikegami and Grass Valley camera heads must be correspondingly diverse: studio cameras, hand cameras, steadicams. These are fully compatible with the HDwireless RF1’s “Wireless Link System”. A fundamental distinction must be made between integrated solutions and add-on technologies. Side panel solutions are available for Sony camera heads, in which the transmission technology is located in the side cover. For fibre optic or TRIAX-bound cameras, the transmitter can be used within a few minutes without the need to update the camera’s software. For RF use as a studio or handheld camera, the only visible differences are the additional antennas for video transmission and camera control. The Grass Valley INCAM-G wireless camera system provides a fully integrated solution for the Grass Valley LDX series. As an alternative to these solutions, add-on transmitters can be connected to the camera head using a mounting plate. The camera and transmitter are powered using “power through the line” technology via the camera battery, which for example allows Steadicam wireless cameras to be as handy as possible. For high-resolution video transmissions, HDwireless HCAM is available as a new 4k wireless camera system for live image transmission to the RF1 mobile production unit.
The most recent example of an extensive wireless camera transmission using the HDwireless production vehicle RF1 was “Schlager, Stars & Sterne – Die Schlossparty in Österreich” …
… with Florian Silbereisen on June 2nd, 2018. Commissioned by the German public broadcaster Mitteldeutscher Rundfunk, HDwireless ensured extensive video radio transmission in Kitzbühel, Austria. Several wireless cameras were used for the primetime live show broadcast on Saturday evening on public TV stations ARD and ORF – including the very lightweight HDwireless ULC EVO2 Steadicam system. The cameras’ live images were received via remote antennas as a network-based ASI signal and were transmitted to the RF production vehicle via fibre optics. The transport stream’s decoding was ensured by the RF1’s technology from where video signals were then transferred to the OB van. In addition to video radio transmission, HDwireless was also responsible for the communications radio, which was provided via the vehicle’s transmission technology. CEO Patrick Nussbaum on the deployment of his HDwireless team: “We planned and implemented the wireless camera transmission in close cooperation with the MDR. Among other things, a remote camera on a neighbouring golf course had to be included, which provided live images of a helicopter landing. For the transmission of all signals, reliable transmission with stable video signals from our RF1 was ensured.”
“HDwireless RF1 is equipped with the latest wireless systems for complete control of all wireless cameras.”
The wireless cameras’ control functions are connected to the RF production vehicle via radio so that each camera can be fully controlled. The transmitter transmits the control signals from the production vehicle to the cameras in the frequency range between 435 and 490 MHz, while the control hardware on board can be controlled via Ethernet. The operator can thus either work in the RF1 vehicle itself or control the cameras from an OB truck. In the latter case, the connection is ensured via a data cable connecting the OB van to the RF1.
“In the end, all radio frequencies converge centrally here in the HDwireless RF1.”
Every frequency that is used in the course of a production and that is received by the RF production vehicle is measured, analysed and processed. RF receivers indicate signal strengths and qualities. Is each wireless camera system sending perfectly decodable signals from its assigned work area? Is the signal strong and stable enough in time for processing? Are the registered and licensed frequencies free of interference? The RF technician in the HDwireless RF1 analyses and evaluates all these questions and aspects with the help of control displays and RF measurement technology. For each project, the task is unique and depends on factors such as the size and topography of a broadcasting area or on the nature of a location. The project-dependent RF concept determines the antenna setup. Often, antennas are not only located on the production vehicle’s mast, but also at remote positions with ideal reception positions – for example on buildings or elevations. Remote antennas are conducted loss-free over longer distances with the so-called HDwireless RFiber connection via fibre optics. Depending on the production, the RF1 also receives signals from established antenna networks. FC Bayern Munich’s championship celebration at Marienplatz in Munich, Germany, on May 20th, 2018, is an excellent example of the HDwireless RF1’s effective RF production structure. During this production, several RF radio tasks were performed using the RF1. The production vehicle’s antenna technology received live images from the various wireless cameras located on the square, in the town hall and on its balcony as well as via a radio link from the church tower of St. Peter. Additionally to the live images, the audio signals from the presenters’ microphones were received via the RF antennas on the vehicle’s high antenna mast. The complete communication radio, including recording manager and directional radio, was also handled from here.
“It’s an obvious choice to use the RF1’s potential at the production site for communication radio as well.”
The RF production vehicle’s infrastructure includes the integration of communication using Clear-Com FreeSpeak II at 1.9 GHz and 2.4 GHz. This way, radio network plots can be set up for the desired application area from the vehicle. Using fibre optics or network cable, the wireless intercom area can be extended to many square kilometres. Typical radio tasks also include the transmission of presenters’ microphones. For the championship celebration in Munich, this meant a complete supply of the presenters micros’ radio transmission with the return transmission of the sound mix N-1 on the one hand and the supply with the communication radio for direction, recording management and team on the other hand. During the production in Munich, the radio coverage included the city hall, Marienplatz, the TV compound and the more distant church St. Peter. For this purpose, HDwireless used Clear-Com FreeSpeak II and digital Motorola UHF radio cells. “An all-in-one solution with many options for RF transmission.” The importance of wireless camera transmissions for broadcasting is constantly increasing. At the same time, the demand for complex and demanding implementations requires high-quality and reliable RF solutions. An important component is the HDwireless RF1 as the central interface for high-frequency transmission of all types of radio signals during TV productions and events. Patrick Nussbaum sums up: “The customer benefit is the reliable and stable provision of all desired output signals, from video and data to on-site communication – even in large broadcasting areas.”