Today’s IoT project designers are continuously looking for opportunities to reach new ultra-low levels of power consumption for constrained IoT applications such as asset tracking, supply chain and logistics management, smart agriculture, smart cities, and environmental monitoring. This quest leads designers to consider LoRa, a non-cellular low-power wide-area (LPWA) network technology.
However, a key shortcoming of LoRaWAN is precisely what it touts as its strength: low bandwidth. Compared with cellular connectivity, and because of the frequency bands it utilises, LoRaWAN doesn’t allow continuous messaging, making it suitable only for short periodic communication.
Many IoT devices require location information to do the job. While LoRaWAN offers distinctive low power benefits that make its GPS-free geolocation feature seem like an attractive alternative to a more traditional power-hungry GNSS approach, its location accuracy is insufficient for many IoT applications that require less than 10 m location accuracy. This is where GNSS receiver modules come into the design consideration.
A second shortcoming of GNSS devices is the need for assistance data in the form of AGPS to speed up the TTFF. This AGPS system needs connectivity to be able to download the required data, to reduce the TTFF to mere seconds.
u-blox now has an innovative cloud-based positioning solution. The M10 ultra-low-power GNSS receiver module, in combination with CloudLocate, the u-blox positioning-in-the-cloud service, are ideally suited for power-constrained applications that require large power autonomy, a reasonable position accuracy of a few metres, a few location updates per day, and where location information is not used on the device itself.
This innovative positioning solution brings power autonomy to constrained IoT devices by offloading position calculation to the cloud. Because the GNSS signals are pre-processed on the receiver, the solution works with a tiny data packet size of 12 to 50 bytes. u-blox’s CloudLocate uses only the uplink connection to the cloud to resolve position without the need for traditional assistance data, making this technology the perfect complement for a low bandwidth LoRaWAN solution that also requires metre-level position accuracy.
During operation the GNSS signals are first pre-processed on the receiver, and then a data packet size of 12 to 50 bytes is transmitted to the cloud, where the power-intensive position calculation is performed, off the actual device. No downlink is needed, because location information is not used on the device itself, but rather by a cloud service. In this way, CloudLocate is ideally suited even for IoT applications in limited bandwidth networks such as LoRaWAN that have no suitable downlink.
The MAX-M10 supports concurrent reception of four GNSSs (GPS, GLONASS, Galileo, and BeiDou). The high number of visible satellites enables the receiver to select the best signals. This maximises the position availability, under challenging conditions such as in deep urban canyons. u-blox Super-S technology offers great RF sensitivity and can improve the dynamic position accuracy by up to 25% with small antennas or in a non-line-of-sight scenario.
The u-blox MAX-M10S GNSS modules are designed to operate with extremely low power consumption, using less than 25 mW in continuous tracking mode, without compromising GNSS performance. The overall power consumption can be reduced further by minimising the time that the GNSS receiver is switched on and by outsourcing the power-intensive position calculation off the device and to the cloud. CloudLocate does exactly that, saving up to 90% of power consumption and acquisition time compared to a standalone GNSS. A position request can consume as little as 25 µW/h, meaning months spent in the field before needing charging.
This exciting platform is being used by Move-X on the Cicerone board, a LoRaWAN radio connectivity solution. This board is built around a Move-X radio module that provides both LoRaWAN connectivity and processing power for the user application. It can be operated via a single-cell LiPo battery and embeds a charging circuit, and is the ideal platform for developing IoT projects using cloud-based positioning and LoRaWAN.
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