All functions of an A-SMGCS depend on quality and reliability of the Surveillance data. As of now, there is no transparency for operators and users, i.e. air traffic controllers, Airport Operators (AO), and Air Navigation Service Providers (ANSP), when it comes to actual data quality and integrity. How exactly does the representation of a target on the synthetic surface situation represent the positions in reality? What information is actually based on measured values, i.e. actual sensor outputs, and what is based solely on extrapolation and other methods of data post processing? Can the operational person fully rely on the A-SMGCS?
To date, it has simply been impossible to acquire a neutral analysis of an existing Surveillance systems. For this reason, the manufacturers and suppliers of the A-SMGCS components were usually contracted to evaluate the systems they had previously delivered. The results of these analyses can easily be imagined. Because of the new A-SMGCS Functions and the additional requirements that go along with them, it is now becoming more and more apparent that many systems currently in use do not actually deliver what they pretend to deliver. Oftentimes, this surfaces by causing problems with the tuning of warnings and alarms of the Airport Safety Support Service or when a Guidance Function is implemented, e.g. Follow-the-Greens.
A dual assessment strategy seems best to remedy this situation:
1. Our partner Fraport AG is technically capable of performing in-depth analyzes of existing Surveillance Functions according to each individual quality criterion defined in the EUROCAE standards ED-87C and ED-117A. This is in principle possible at any airport with an A-SMGCS, independent from the supplier and the complexity of the system. This is achievable thanks to high-precision reference positioning systems installed in a van. In just a few days, tens or hundreds of thousands of reference measurement points can be generated, later to be compared with the individual sensor system outputs of the Surface Movement Radar (SMR) and the Multilateration System (MLAT) as well as to the system tracks generated by the local Multi Sensor Data Fusion (MSDF). It is strongly recommended to perform a neutral quality check of this kind before implementing new A-SMGCS functions and whenever the actual quality is subject to operational problems or questionable. If a non-conformance with the requirements of the standards is identified, such as an insufficient Reported Position Accuracy (RPA) or an inadequate Track Continuity (TC), it is highly advisable to immediately take appropriate action. In the case of subsequent improvements, it is then technically possible and highly recommended to check whether the measures taken actually deliver the desired improvement.
2. Independent of whether or not an independent analysis based on highly accurate reference points was performed as described above, a continuous monitoring of the Reported Position Accuracy, the most important Surveillance System quality criterion, can be carried out easily and precisely with the help of MagSense Air. This continuous data quality and integrity monitoring concept is based on the comparison of actual times of aircraft or vehicles exactly above a MagSense Air sensor with the position of the same mobile at the exact same time as detected by SMR, MLAT or MSDF. This monitoring concept is capable of detecting changes in RPA, which are either creeping or caused by construction measures, sensor failures or other influencing variables such as dynamic shading.
If an airport performs an initial assessment of the prevailing surveillance integrity and quality, takes measures to overcome existing deficiencies and keeps incessantly monitoring the RPA quality, the probability of being able to implement and use an Airport Safety Support Service and a Follow-the-Greens as intended, is highly increased. Even if no new A-SMGCS Function shall be implemented at an airport, a holistic assessment and a continuous RPA monitoring can be used to build additional system trust with the users and to sort out potential problems previously unknown.