Iridium Terminal
Objective
In line with a range of activities to enhance their product portfolio, Iridium Satellite selected Cambridge Consultants to act as their strategic wireless technology consultant, developing their next-generation ground-based terminal equipment. Cambridge Consultants assembled a multi-disciplinary engineering team of around thirty-five people, with expertise in satellite communications, to act as the design authority for these enhancements.
The enhancements were to accomplish two objectives - to update the design in line with latest proven technology, as well as to develop a powerful and flexible platform that could act as the foundation for other product derivatives in the future.
Approach
This work began by upgrading Iridium's existing 9505 handset. The work centred on the re-design of the radio transceiver in all design domains, including RF, analogue, baseband, DSP, software, and mechanical and industrial design.
A critical design constraint was the obvious need to retain compatibility with the existing satellite and ground infrastructure and the system's 'air interface specification'. However, to provide future flexibility and to minimise development time and risk, the analogue/digital boundary was moved closer to the antenna.
Result
This 'software radio' approach of moving the analogue/digital boundary reduced the analogue component count and facilitated product enhancements being effected in the digital domain.
Furthermore, the new handset design uses lower power consumption components and incorporates upgraded battery technology to increase standby and talk time. A dominant contributor to these power consumption savings was a new 8 watt power amplifier, which provides not only a smaller footprint but also dramatically improves efficiency, thus further extending battery life.
Additionally, the programme, which was completed on time, was also subject to other constraints in the manufacturing arena. For example, pre-empting the ROHS regulations that come into force in 2006, lead-free components were introduced to ease the transition for the current and future product derivatives. Furthermore, the new design maximised re-use of existing production assembly and test infrastructure.
Benefit
Cambridge Consultants were able to facilitate Iridium Satellite moving to a new era in their burgeoning business. A key reason why we were selected was the fact that we were able to span the variety of disciplines within what is a highly complex product. Having completed the initial development, we are now focussed on adding new features to Iridium's product portfolio. These include an advanced packet-based data communications capability that will extend the performance of the Iridium network in application areas such as supply chain management and remote monitoring. The new capabilities will appear on Iridium's forthcoming '9600' data modem.