“With consumers expecting reliable location services everywhere, we had to rewrite the traditional rule book on GPS architectures and create a new, low-energy way to maintain continuous location awareness without draining the device battery or requiring network assistance,” said Kanwar Chadha, chief marketing officer for CSR and founder of SiRF. “With SiRFstarIV and our unique SiRFaware technology, we have developed an architecture that will not only significantly improve the consumer experience when navigating with smartphones, but also enable consumer devices to maintain continuous location awareness.”
To maintains hot-start conditions with minimal energy (50-500 microamperes) CSR has essentially blended together the following techniques: opportunistic ephemeris decode, advanced power management, local ephemeris prediction as well as what SiRF is calling “Dynamic contextual awareness”, based on monitoring temperature change and available sensors to detect movement and predict sky view availability to conserve power and boost performance.
This new architecture is also comprised of a high-performance GPS location engine (twice the search capacity of the previous SiRFstarIII architecture), an intelligent MEMs sensor support (for accelerometers and other sensors) and advanced DSP technology that actively searches for jammers and removes them prior to correlation.
The first implementation of the SiRFstarIV architecture, the GSD4t host-based platform, is optimized for mobile phones and other space and power-sensitive consumer devices. The GSD4t receiver is said to provide solid performance, with navigation to -160 dBm and tracking to -163 dBm. In terms of power consumption, the GSD4t receiver requires only 8 mW in 1-Hz TricklePower mode – two and a half times less than the previous SiRFstarIII.
The SiRF GSD4t receiver is available now in sample quantities, with production quantities planned for October, said CSR.