Improved position accuracy and power consumption with MAX-M10N and AssistNow

Use cases like wearables, vehicle, people, pet, livestock or asset tracking all require a GNSS chip or module to calculate a precise position. These devices are typically battery-powered and heavily constrained in terms of size and energy consumption. Optimizing power efficiency is therefore an important parameter to work on in the design phase.  

The challenge: antenna limitations

Small devices naturally use small antennas. An ideal GNSS antenna is right-hand circularly polarized and oriented toward the sky to ensure strong satellite signals. In practice, size constraints often prevent such optimal designs.

As a result, GNSS performance suffers:

• Small or misaligned antennas lead to weak signal levels.
• Frequent signal drops interrupt the download of ephemeris and ionospheric correction data.
• The GNSS chip must repeatedly search for signals, which drives power consumption up compared to a device with a larger antenna and clear sky view.

Such scenario drives trade-off decisions between device size, power consumption and positioning accuracy, a common issue in IoT and tracking applications. 

The solution: Assisted GNSS

Assisted GNSS (A-GNSS) services like u-blox AsssistNow provide an easy way to overcome these challenges.  

Instead of downloading ephemeris and correction data over the satellite link, AssistNow delivers this information via the Internet. The data can be stored locally on the device, ensuring it is always available.

The benefits are significant:

• Shorter signal acquisition phase → lower GNSS power consumption
• Instant ephemeris data availability with AssistNow Live Orbits → improved position accuracy and availability

AssistNow is a u-blox A-GNSS service to achieve premium performance in challenging IoT environments. The service is flexible in payload size and data validity to adopt to the use case constraints.

AssistNow Predictive Orbits offers a faster time-to-first-fix (TTFF) by providing orbit prediction data and almanac of the GNSS satellites for up to 14 days. Beside a fast TTFF the AssistNow Live Orbits download every 2-4 hours improves the position accuracy significantly.

The image below shows the benefits in an asset tracking use case. Without AssistNow, the TTFF is around 30 s and the positioning accuracy is about 12 m. With AssistNow Live Orbits, TTFF drops to just 1 s and positioning accuracy improves by roughly 50%.

Real-world benefits

Tracking devices with small GNSS antennas face inherent challenges. In our blog about LEAP for industrial uses cases, we explain these issues and show power-saving strategies for pet trackers, livestock trackers and vehicle tracking scenarios.  

Even after power consumption is brought down to an acceptable level, many applications still require better positioning accuracy and availability. This is especially true for applications like pet tracking, wearable devices and asset monitoring, where reliable performance under real-world conditions is critical.

In  a dog tracker scenario we tested a u-blox M10 product with LEAP (Low Energy Accurate Positioning) mode: 

1. LEAP mode alone reduced power consumption by 40%.

2. Adding AssistNow Live Orbits cuts power consumption by a further ~20%, while increasing position accuracy by 40%.

    

 

Similar results can be expected in wearable, vehicle, people, pet, livestock use cases with small antennas as well.

Conclusion

u-blox AssistNow helps to reduce power consumption and increase position accuracy with small GNSS antennas. For wearable, vehicle, people, pet, livestock use cases it is an excellent choice to push performance to a new limit.  

Implementation is rather easy and in the bundled offer available with UBX-M10150-KB-AN chip or the MAX-M10N module the lifetime access to AssistNow Predictive Orbits and AssistNow Live Orbits service is already included in the hardware price, eliminating  the risk of unpredictable operational costs in your business case calculation.