Sub-miniature GNSS tracker
The Brief
Our client wanted an undetectable, ultra-low-power location device to be used to discreetly track high-value items in several different usage scenarios. As well as the tracking function, the device needed to have the ability to be integrated with other sensors and functions.
The real challenge was to accommodate the full range of scenarios: months of lying dormant followed by a period of intense activity, then an extended period of location reporting at regular intervals.
Additionally, the device needed to be re-configurable remotely in the field, without compromising the strict power usage requirements.
The Solution
We began by creating a usage model to analyze the primary power-consuming functions. Using different behavioural models, we determined how the devices could be optimized for minimum power consumption across the board. Further investigations helped us match optimal technologies and devices to the product functions.
Meeting the extremely low power usage expectations could not simply be achieved by component selection alone. Therefore, we took an integrated approach that involved matching a suite of key components and accessing their low-power modes using lower-level embedded software. This allowed them to work together in a power-efficient manner. Additionally, application layer embedded code was used to intelligently configure various high-level usage profiles.
Our multi-layer cross-system approach was necessary to achieve the exacting power requirements of the product. We also developed a clever live remote configuration scheme that enables the system administrator to manage and re-purpose devices in the field for further power optimization and functional re-profiling. This can be done without significantly impacting the battery charge life.
Our extensive knowledge of sensor technology and processor sub-systems afforded us the ability to select the optimum combination of components from a size, power and function perspective.
A deep understanding of the PCB layout process and its limitations allowed us to compress the solution into the smallest physical footprint possible whilst still meeting production and conformance criteria.
We have an intimate knowledge of coding for a wide range of processors and a deep understanding from driver level up to embedded applications. This ensured we extracted the maximum performance using minimum power from the devices selected.
Domain experience allowed us to deploy several tricks to achieve market-leading performance of the product.
Experience of an integrated approach to hardware and software design enabled us to architect a system solution that from a function and power perspective was greater than the sum of its parts.