Invacom and Raven Manufacturing of the United Kingdom teamed up with ESA to develop the world's least expensive Outdoor Units (ODU's) and antennas for DVB-RCS systems. A target price for a 2W Ku-band output power unit, including an 80cm antenna, can reach less than 400 euro in production volumes of 1000.The low cost of the new units represents a substantial price reduction compared to those previously available and will become even more substantial with larger production runs. According to Rolv Midthassel the ESA Telecom Technical Officer responsible for the project, "This price reduction is critical if ODU and DVB-RCS systems are going to become commercially viable."
The ODU and the antennas are vital parts of DVB-RCS terminals and have so far been the dominant cost factor of the overall terminal solution. Such a terminal requires an Indoor Unit (IDU) - a set top box which provides the user interface - and an Outdoor Unit (ODU) connected to a satellite receiving antenna. Current systems have good performance; the only problem which prevents wider use of this kind of terminal is its high cost.
"Other systems are already providing internet access through wireless LAN or similar technologies. However, as DVB-RCS terminals become affordable, internet access will become attractive for end users, be it consumers or SOHO's (Small-Office-Home-Office), in remote areas which cannot yet access such connections. This will mean a further shrinking of the digital divide," Midthassel added.
The project began when Eutelsat challenged companies to come up with a low-cost alternative. Invacom and Raven put their talents together, with Invacom assigned the task of redesigning the ODU itself and Raven the antenna. To achieve the specified 400 euro goal, the team had to incorporate low cost philosophy into the design of the ODU's.
One part of the adopted design philosophy is the use of only surface mount components which enables a lower manufacturing cost. In addition, filters used to reduce unwanted emissions in line with ETSI specifications are realised using moulding techniques instead of the more common and more expensive milling technique. Finally, the ODU's requires only limited tuning, saving assembly and test time and thereby reducing costs further.
Three different ODU's were built during the project, a 2W constant gain ODU, a 2W and a 1W constant output power ODU. A low power 0.5 Watt version was dropped during the project as there was little demand expected. Raven's role in the team was to contribute two easy-to-install antennae with diameters of 70cm and 83cm. Both companies have a contract with Eutelsat to deliver ODU's, it is expected that Eutelsat will look for a provider of the IDU component.