u-blox of Switzerland has introduced a GPS receiver that works with inertial sensors to add dead-reckoning navigation when satellites signals are weak or before the receiver has locked-on.

It requires an external MEMS inertial sensor and flash memory, and also works with other satellite navigation (GNSS) systems (list below).“EVA-M8E adapts automatically to installations anywhere within a vehicle. Dead-reckoning with adaptive signal strength compensation helps reduce the effects of small antenna and poor installations. This makes EVA-M8E ideal for extremely small after-market road-vehicle applications such as usage-based insurance and theft alarms.”

Power consumption is 29mA at 3V (plus a 1.4-3.6V back-up supply), which the firm feels is low enough to allow ‘untethered’ operation – operation without connection to the vehicle electrical supply.

The external inertial system needs to include 3D accelerometers and 3D gyros.

While a list of recommended MEMS sensors, or an appropriate specification, remains illusive, the firm’s C93-M8E dashboard-top GNSS+dead reckoning reference design (pictured) appears to use a Bosch Sensortec BMI160.

Applications are expected in self-contained car trackers – to be used in conjunction with insurance policies, for example… Read the full article at Electronics Weekly