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u-blox A-GNSS services


  • Improves GNSS performance
  • Lock onto your position instantly
  • Free service is available for all u‑blox GNSS products
  • Fast time‑to‑first‑fix, even in challenging environments
  • Improved accuracy and position availability
  • Improved power consumption
  • Global coverage, network operator independent
  • No additional hardware required
  • Guaranteed Service Level option for premium customers
  • Easy to install and use
AssistNow Icon

    AssistNow accelerates calculation of position by delivering satellite data such as ephemeris, almanac, accurate time, and satellite status to the GNSS receiver via wireless networks or the internet. This aiding data enables u‑blox GNSS receivers to compute a position within seconds, even under poor signal conditions.

    The Challenge

    GNSS users expect instant position information. With standard positioning, this is often not possible, because at least four satellites must be identified, and their complete orbital position data (called ephemeris) must be received. Under adverse signal conditions, data downloads from the satellites to the receiver can take minutes, hours, or even fail altogether.

    AssistNow A‑GNSS services 

    AssistNow Online and AssistNow Offline are u‑blox’s end‑to‑end AssistNow A‑GNSS services for OEM customers and their end users. These services boost GNSS acquisition performance for devices with or without network connectivity. AssistNow Online and AssistNow Offline can either be used alone or in combination. AssistNow A‑GNSS services do not require any additional hardware and generate barely any CPU load. The system is very easy to implement and can be installed and operated within a day. u‑blox wireless modules feature an embedded AssistNow client making integration simple.

    For further information on AssistNow Online and Offline, see the product summary.

    Free and premium service options 

    AssistNow data is collected by u‑blox’s global array of satellite receivers, and maintained in real‑time on u‑blox AssistNow servers that are accessible via the internet. For best effort applications, u‑blox provides AssistNow free‑of‑charge to its customers using u‑blox GNSS receivers. For applications requiring a guaranteed minimum Quality of Service (QoS), u‑blox provides AssistNow Premium, which provides guaranteed availability based on a service level agreement and 24/7 support. To register for AssistNow, see our AssistNow Service Registration.

    AssistNow Autonomous 

    AssistNow Autonomous is an embedded feature available free ‑of ‑charge that accelerates GNSS positioning by capitalizing on the periodic nature of GNSS satellite orbits. GNSS orbit predictions are directly calculated by the GNSS receiver and no external aiding data or connectivity is required. AssistNow Autonomous can be used alone, or together with AssistNow Online for increased positioning speed and accuracy.

    u‑blox products compatible with AssistNow:

    The challenge

    Satellites, Car and City

    AssistNow Online

    AssistNow Offline


    AssistNow Icon