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TECHNICAL PUBLICATION Dynamic models tuned for application The ProPoint engine allows selection of a dynamic model that best suits the application. Using data collected in a variety of applications, models have been created that are used as inputs to the engine. Off-road vehicle models that allow for wheel slippage and sideways movement contrast to on-road automotive models which expect the vehicle heading and direction of travel to be the same. The marine model allows for side-to-side motion and lateral drifting. Robust estimation techniques for detection of outliers The ProPoint engine identifies, within the received input data, any measurement that does not match a stochastic model. For each measurement that doesn't match its stochastic model, the engine will either reject the measurement, adjust the stochastic model assigned to the measurement or correct the measurement. The method generally enables the provision of a precise position estimation even in the presence of measurements containing one or more outliers. Positioning Modes The Trimble ProPoint Engine supports a variety of GNSS only and GNSS/INS positioning modes. These include the following: ► Precise Positioning: ► GNSS-SBAS, GNSS-DGNSS, GNSS- RTK, GNSS-RTX ► Precise Positioning with Orientation: ► GNSS/INS-SBAS, GNSS/INS-DGNSS, GNSS/INS-RTK, GNSS/INS-RTX Depending on the availability of differential corrections the engine will gracefully transition positioning modes to deliver uninterrupted positioning. Integrated RTK xFill During periods of radio outage when the base station correction stream is unavailable to support conventional single-base or Virtual Reference Station (VRS) Network RTK, Trimble xFill provides the technology that enables positioning to continue for short periods with centimeter-level precisions. Not only does this eliminate positioning drop-outs, it also enables a brief excursion into an area masked from the reference radio signal, yet still visible to the GNSS constellations. To achieve centimeter positioning with GNSS signals, Trimble xFill™ provides a specialized correction stream broadcast by L-band satellite that is generated using Trimble Real-time eXtended (RTX) technology. The Trimble xFill technology is able to produce RTK positions with precision levels similar to traditional differential RTK because it mitigates the same source of errors. The satellite clock, orbit, and measurement biases that are cancelled via differencing in standard RTK processing are modeled and transmitted as part of the Trimble RTX® correction stream. These effects then become known quantities and can be properly accounted for when processing the rover measurements. The atmospheric errors are dealt with by algorithms specifically developed for the Trimble RTX system, reducing any residual effects to an acceptable level for high accuracy GNSS positioning applications. As a result, the overall Trimble RTX data processing provides modeling of the residual errors on the satellite observations that are comparable to the ones achieved with RTK. Leverage CPU capacity in modern platforms As the number of GNSS signals increases so does the computing power required to process all measurements. To address this challenge,

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