The reliability of carrier phase DGPS position solutions in a high-dynamical environment.: The truth reference, the whole truth reference and nothing but the truth reference?

In this report, some tests are described which have been used to determine the reliability of carrier-phase DGPS position solutions, especially in a dynamical environment, such as an aircraft. Research has been done to determine the reliability of the acceptance test, used to determine whether a carrier-phase DGPS position solution is the ’true’...

Eurofix : Ternary modulation and error control coding

The Eurofix navigation system is intended to overcome the problems of the GPS satellite navigation system by broadcasting corrections for this system using existing LORAN-C transmitters. By modulating the pulses transmitted by the LORAN-C stations, a low speed digital communication channel becomes available. This datalink must fulfill a number...

Error Analysis of the Navigation Function in respect of the RNP Tunnel Concept

The RNP parameters are used to define the tunnel boudaries, such that the TSE will be inside the tunnel, and consequently will meet the demanded requirements. The TSE is the difference between the aircraft’s actual position and the desired flight path, and is a result of disturbances on the AFCS. In this thesis a model of the AFCS is presented,...

Validation and optimization of the Kalman filter in MIAS

The use of a Kalman filter in MIAS is discussed along with the dynamic model in the Kalman filter. Several error sources are treated, like non-optimal tuning, MLS biases, timing of the asynchronous input signals and airborne antennae displacement

Eurofix and GNSS: The possibility of integrating GLONASS into Eurofix

Currently, two independent Global Navigation Satellite Systems (GNSS) are under development: the Global Positioning System (GPS) and Global Orbiting Navigation Satellite System (GLONASS). For harbour approaches a 95% horizontal position accuracy of 8-20m is required. Due to several error sources, this accuracy can not be met by stand alone GNSS....

Modulation Schemes for the Eurofix Datalink

In the Eurofix system DGPS corrections are transmitted using the Loran-C signal as a datalink by time shifting the Loran-C pulses. The performance of the datalink, however, is bounded by restrictions of both the Loran-C system and the DGPS system. First, the normal Loran-C performance should not degrade noticeably due to the extra data...

Modelling of the Eurofix Data-Link

After an introduction of the Eurofix concept for transmission of Differential GPS data via Loran-C signals by delay modulation, the modelling of this principle is discussed. The results of the model are compared with real measurements. The results of this comparison will be analysed and some final remarks about the quality of the data link will...

MIAS real-time positioning and integrity monitoring: Multi-mode Integrated Approach System

This report describes the design requirements and the functional design for the implementation of real time control and position calculation of the MIAS airborne part. Important issues for this implementation are the timing of the asynchronous measurements. The setup used for the MIAS flights tests in 1994 and the results of these flight tests...

EUROFIX Integrity

From a system point of view four aspects are identified that influence the integrity of EUROFIX, an integrated radionavigation system that combines DGPS and LORAN-C. The four aspects are: the EUROFIX Ground Segment, the EUROFIX datalink, the EUROFIX user equipment and the information that will be transmitted over the EUROFIX datalink. For the...

A MIAS System Model

A System Model of the MLS Integrated Approach System has been designed using Object-Oriented modeling techniques for the basis of the system and several identification techniques for the modeling of error sources. Different models of MLS and DGPS have been used to perform the actual functioning of the MIAS System Model. From running the...

Terminal area navigation : A New Perspective

This paper will try to find answers to the growing demand on capacity in civil aviation. Due to the continuing expansion of civil air traffic, authorities have to cope with a complex set issues that cannot be answered easily. They have the need to accommodate a growing number of aircraft landings, but on the other hand have to maintain the...

Analysis of the Eurofix Data Link

After the introduction of the Eurofix concept for transmission of Differential GPS data via Loran-C signals by additional phase modulation, the consequences of this modulation for conventional (non-Eurofix) users is discussed. In what follows, various modulation schemes will be introduced and the properties of these schemes will be described.

The implementation and evaluation of a Kalman filter in MIAS

This report describes least squares estimation (LSE) and Kalman filtering in integrated navigation. The Kalman filter and its underlying principles are treated. The implementation of a Kalman filter in MIAS is investigated, and two different Kalman filters are developed. The problems that occur in a hybrid environment as the asynchronicity of...

The Asynchronous Correction Concept for High Precision DGPS in Eurofix

The principle of the asynchronous DGPS correction offers many advantages over the synchronous correction principle as used in the standard RTCM recommendations. Especially for low bit rate DGPS, the accuracy is improved considerably by the combined use of an atomic time reference in the DGPS reference station and the application of an...