Honeywell International Inc.

Honeywell G.m.b.h.

Mats Anders Brenner

Randy J Reuter

Kim A Class

Bruce G Johnson

Joseph E Scheitlin

John M Howard

John R Morrison

Zdenek Kana

James Arthur McDonald

Mark A Ahlbrecht

Lawrence C Vallot

Brian W Schipper

Milos Sotak

Kevin D Vanderwerf

Rudolf C Dankwort

Tamim F El-Wailly

Danny Thomas Kimmel

Pavel Ptacek

Tomas Beda

Pavol Malinak

Justin Joseph Syrstad

Jay Joseph Hansen

Martin Musil

Paul A Kline

James Arthur Mcdonald

Randy L Reuter

Systems and methods for fault detection, exclusion, isolation, and re-configuration of navigation sensors using an abstraction layer are provided. In certain embodiments, a system includes a plurality of sensors that provide redundant sensor measurements, wherein redundancy of the redundant sensor measurements is achieved based on an independence between measurements from different physical sensor units in the plurality of sensors. The system additionally includes a fusion function configured to receive the redundant sensor measurements from each sensor in the plurality of sensors and calculate fused navigation parameters. Further, the system includes an abstraction layer that calculates an estimated state based on the fused navigation parameters, wherein the estimated state comprises safety assessment information for the fused navigation parameters and the fused navigation parameters. Moreover, the system includes a plurality of user systems, wherein each user system in the plurality of user systems receives the estimated state from the abstraction layer.

Fault detection, exclusion, isolation, and re-configuration of navigation sensors using an abstraction layer

Systems and methods for integrity monitoring of primary and derived parameters are described herein. In certain embodiments, a method includes transforming an estimated error state covariance matrix of at least one primary integrity monitoring parameter of a navigation system onto an error state covariance matrix of one or more derived integrity monitoring parameters, wherein the one or more derived integrity monitoring parameters depends from the at least one primary integrity monitoring parameter. The method also includes transforming an integrity threshold of the at least one primary integrity monitoring parameter onto separation parameters of the one or more derived integrity monitoring parameters. The method further includes computing a protection limit for the one or more derived integrity monitoring parameters.

Integrity monitoring of primary and derived parameters

A method of supplementing a satellite based augmentation system approach during low visibility conditions is provided. The method includes acquiring satellite range measurements and additional measurements from at least one additional onboard independent sensor. Core sigma values are assigned for satellite range measurements and for each additional measurement from the at least one additional onboard independent sensor. A weighted position solution is determined using the acquired satellite range measurements, the acquired additional measurements and the assigned core sigma values. A discriminator is applied that utilizes vehicle positions derived from the acquired satellite range measurements and from the additional measurements to determine if a fault is present in the weighted position solution. An alert is generated if an output of the discriminator is outside a set tolerance value needed for low visibility operation.

Supplemental system for a satellite based approach during low visibility conditions

A Global Navigation Satellite System (GNSS) based navigation system with signal fault detection is provided. A least one controller is configured to; determine a true carrier phase measurement associated with each satellite signal received at each antenna of a plurality of spaced antennas; resolve integer ambiguities in true carrier phase measurement differences; and calculate at least one variable of a first navigation solution based on the obtained first set of resolved integer ambiguity measurements. The at least one controller is further configured to apply a solution separation process to repeatedly; calculate the at least one variable of a second navigation solution; determine a difference between the at least one variable of the second navigation solution and the first navigation solution; and detect a fault in satellite signals when the determined difference exceeds a defined threshold.

Signal fault detection for global navigation satellite system using multiple antennas

A method of operating a global positioning receiver is provided. The method includes receiving a plurality of signals from a plurality of satellites. At least a measurement from and location of each satellite is determined based on the received plurality of signals. An approximate vehicle velocity vector is determined based on the received plurality of signals. A dot product between a line of sight between each satellite and a vehicle having the receiver and the determined vehicle velocity vector is determined. Each measurement associated with each determined dot product that is below a minimum dot product threshold is removed to obtain a resultant set of measurements. A position solution based on the resultant set of measurements is then determined.

Intelligent satellite exclusion for multipath mitigation based on line of sight

Systems and methods for a code carrier divergence (CCD) high-pass filter monitor are provided. In one embodiment, a signal deformation monitor for a GNSS ground based augmentation station, the monitor comprising: a CCD monitor stage communicatively coupled to a plurality of GNSS reference receivers, wherein the CCD monitor stage inputs raw pseudorange code measurements and accumulated delta range carrier measurements from each of the plurality of GNSS reference receivers; and a Code Carrier Divergence -High Pass Filer (CCD-HPF) monitor stage communicatively coupled to the CCD monitor stage, wherein the CCD-HPF monitor processes each of a plurality of low-pass filtered divergence rate measurements, dproduced by the CCD monitor stage through a high-pass filter to calculate an averaged CCD-HPF monitor divergence rate, d; wherein the signal deformation monitor outputs an exclusion signal associated with a GNSS satellite when the averaged CCD-HPF monitor divergence rate, dexceeds an exclusion threshold.

Systems and methods for a code carrier divergence high-pass filter monitor

A method of implementing a real-time screening process for phase scintillation is presented. The method includes detecting a phase scintillation event during a sample time period at a phase scintillation monitor; excluding associated satellite measurement data from further use based on the detection of the phase scintillation event at the phase scintillation monitor; detecting an end to the phase scintillation event at the phase scintillation monitor; and readmitting associated satellite measurement data collected after the end of the phase scintillation event as detected by the phase scintillation monitor.

Satellite measurement screening to protect the integrity of existing monitors in the presence of phase scintillation

Systems and methods for averaging satellite sigmas and readmitting excluded satellite measurements into differential corrections and integrity monitors are provided. In one embodiment, a method comprises: calculating a first RFI based averaged sigma and a second RFI based averaged sigma, wherein the first RFI based averaged sigma includes a sigma for the excluded satellite measurement and wherein the second RFI based averaged sigma does not include the sigma for the excluded satellite measurement; and, readmitting the excluded satellite measurement into either a differential correction broadcast or a respective integrity monitor when the first RFI based averaged sigma is less than or equal to the second RFI based averaged sigma.

Systems and methods for averaging satellite sigmas and readmitting excluded satellite measurements into differential corrections and integrity monitors

Systems and methods for attitude fault detection in an inertial measurement unit (IMU) are disclosed. In one embodiment, an avionics system comprises: an IMU configured to produce a calculated pitch solution, a calculated roll solution, or both; a monitor coupled to the IMU and configured to produce an estimated pitch solution, an estimated roll solution, or both; a comparator, wherein the comparator determines the difference between the calculated pitch solution and the estimated pitch solution, the difference between the calculated roll solution and the estimated roll solution, or both; and a display device communicatively coupled to the comparator; wherein the display device receives a warning message from the comparator when the difference between the calculated pitch solution and the estimated pitch solution is greater than a pitch threshold, or when the difference between the calculated roll solution and the estimated roll solution is greater than a roll threshold, or both.

Systems and methods for attitude fault detection in one or more inertial measurement units

A method of implementing a real-time screening process for amplitude scintillation is presented. The method includes detecting an amplitude scintillation event during a sample time period at an amplitude scintillation monitor; excluding associated satellite measurement data from further use based on the detection of the amplitude scintillation event at the amplitude scintillation monitor; detecting an end to the amplitude scintillation event at the amplitude scintillation monitor; and readmitting associated satellite measurement data collected after the end of the amplitude scintillation event as determined by the amplitude scintillation monitor.

Satellite measurement screening to protect the integrity of existing monitors in the presence of amplitude scintillation

Systems and methods for attitude fault detection based on integrated GNSS/inertial hybrid filter residuals are provided. In one embodiment, a fault detection system for aircraft attitude measurement system comprises: a sensor monitor coupled to a first inertial measurement unit, the sensor monitor comprising: a navigation error model for the first inertial measurement unit, the model configured to model a plurality of error states including at least an attitude error state vector, an velocity error state vector, and a position error state vector determined from data generated by the first inertial measurement unit; and a propagator-estimator configured to propagate and update error states based on GNSS data; and a residual evaluator configured to input measurement error residual values generated by the propagator-estimator, wherein the residual evaluator outputs an alert signal when the measurement error residual values exceed a threshold.

Systems and methods for attitude fault detection based on integrated GNSS/inertial hybrid filter residuals

Systems and methods for attitude fault detection based on air data and aircraft control settings are provided. In one embodiment, a sensor monitor for an aircraft attitude measurement system comprises: an aircraft model configured to model a plurality of states, the plurality of states including at least an aircraft attitude state, an aircraft velocity state, a sink rate error state, and a wind velocity state; a propagator-estimator configured to utilize the plurality of states of the aircraft model to process air data measurements and attitude measurements from a first inertial measurement unit of the aircraft attitude measurement system; and a residual evaluator configured to input residual error values generated by the propagator-estimator, wherein the residual evaluator outputs an alert signal when the residual error values exceed a predetermined statistical threshold.

Systems and methods for attitude fault detection based on air data and aircraft control settings

Systems and methods for monitoring broadband radio frequency interference are provided. In certain embodiments, a method comprises calculating a smoothed carrier to noise value for a received signal on a processing unit, wherein the received signal is associated with a receiver and at least one satellite; calculating an average jammer power to noise power value for the receiver; calculating an instantaneous carrier to noise value for the received signal based on the average jammer power to noise power value and the smoothed carrier to noise value; comparing the instantaneous carrier to noise value to an exclusion threshold, and determining whether to exclude the received signal from calculations of global positioning data based on the comparison of the instantaneous carrier to noise value to the exclusion threshold; and when the received signal is excluded, monitoring the received signal for readmittance to the calculation of global positioning data.

Systems and methods for monitoring broadband radio frequency interference

A navigation system includes first receiver receiving satellite signals, second receiver receiving differential correction data from ground receivers, and processing device coupled to receivers. Processing device determines correction data for satellite signals based on differential correction; determines position solution based on satellite signals and corresponding differential correction data; determines first position sub-solutions based on satellite signals from all but one satellite (different for each first position sub-solution) and corresponding differential correction data; calculates first separations as function of first differences between position solution and first position sub-solutions; determines second position sub-solutions for mobile object based on satellite signals and corresponding differential correction data from all but one block of ground receivers (different for each second position sub-solution); calculates second separations as function of second differences between position solution and second position sub-solutions; detects error in position solution when one of first separations or second separations exceed corresponding separation limit.

Systems and methods for solution separation for ground-augmented multi-constellation terminal area navigation and precision approach guidance

A processing function to monitor a horizontal delay gradient in satellite signals is provided. The processing function includes a satellite differencing module, a double differencing module, and a gradient estimator module. The satellite differencing module receives carrier phase measurements for at least two satellites from at least two reference receivers that have a known geometric relationship to each other. The satellites include a monitored satellite and at least one other satellite. The satellite differencing module determines differences in the carrier phase measurements between signals from the monitored satellite and at least one other satellite. The double differencing module forms double-differences between pairs of the at least two reference receivers; compensates the double-differences between the pairs for the known difference-in-position of the reference receivers; and averages the double differences. The gradient estimator module estimates a magnitude of the horizontal delay gradient based on the averaged compensated double-differences for the monitored satellite.

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Plymouth, MN, United States of America

Mats Anders Brenner