Ground Based Surveillance Techniques

Surveillance Systems are essential elements of the integrated Air Traffic Management (ATM) operations.

The Surveillance System includes surveillance sensors, surveillance data transmission, surveillance data processing, analysis and support tools. It includes:

  • Airborne Equipment:
    - Surveillance Airborne Equipment like SSR Transponders and ADS-B transceivers
  • Sensors (Cooperative/Non-Cooperative, Dependent/Independent):
    - Primary Surveillance Radar (PSR)
    - Surface Movement Radar/ Aerodrome Surface Detection Equipment (SMR/ASDE)
    - Secondary Surveillance Radar (SSR)
    - SSR Mode S (Select)
    - Automatic Dependent Surveillance-Broadcast (ADS-B)
    - Automatic Dependent Surveillance-Contract (ADS-C)
    - Wide Area Multilateration Systems (WAM)
  • Surveillance Data Processing and Distribution systems:
    - Surveillance Data Processing and Distribution (SDPD)
    - ATM suRveillance Tracker And Server (ARTAS)
    - Surveillance Networks (e.g. RADNET)
    - Surveillance Data Distribution equipment (e.g. RMCDE)
    - Airborne SDPD
  • Surveillance Tools:
    - Surveillance Analysis Support Systems (SASS-Centre)
    - Radar Station Coverage Calculator
    - Screening Angle Analysis from Digitised Terrain
    - Recording, Analysis, Playback & Simulation System for Surveillance Data
    - Mode S Interrogate Code Allocation tool (MICA Tool)
    - Mode S Map Generator and Extraction Tool (for MICA)
    - Recording, etc.

Data delivered by surveillance systems can be used by ATM in various forms for the provision of safe separation of aircraft. SSR Mode S, WAM and ADS-B Surveillance Sensors are able to extract additional Aircraft Derived Data from aircraft.

Mode S

EUROCONTROL were key contributors to the recent development of Mode S.

Mode S groundstations are now deployed throughout many European States – Mode S EHS functionality is providing ATC controllers with additional data items which Mode S ELS functionality is enabling the Aircraft Identification Programme. The majority of aircraft conducting IFR/GAT flights within European airspace are now compliant with Mode S requirements.

Whilst the development of Mode S is essentially complete it is to be noted that deployment and operation of Mode S groundstations is a complex exercise that needs to be conducted in accordance within strictly defined procedures. The following website provides details of the deployment and operation of Mode S Elementary and Mode S Enhanced Surveillance.

Further details on Mode S.

ADS-B

ADS-B is a surveillance technique that relies on aircraft broadcasting their identity, position and other aircraft information from on-board systems via its extended squitter SSR transponder. This signal can be captured on the ground (“ADS-B-out”) or on board other aircraft (“ADS-B-in”) for Air Traffic Situational Awareness (ATSAW) and other airborne separation assistance (ASAS) applications. ADS-B is also being deployed on airport surface vehicles.

In order to meet the surveillance requirements of different environments, ADS-B-out can be used as a sole means of surveillance or in combination with radar or Wide Area Multi-lateration.

As WAM and ADS-B have many synergies, an integrated WAM/ADS-B system is being offered by industry and will become a key element in the future surveillance infrastructure.

The deployment of ADS-B and WAM supports the vision of a cost- and RF spectrum efficient, globally harmonised Surveillance infrastructure achieving the Safety, Performance and Interoperability requirements of the current and future ATM services.

Further details on ADS-B.

WAM

Wide-area multilateration (WAM) is a Surveillance technique that exploits the 1090 MHz transmissions broadcast from aircraft. From these signals it can create a track containing parameters such as aircraft identification, position, height, etc. Active interrogation is also possible in order to trigger transmission.

Multilateration (MLAT) techniques are frequently used to provide airport surveillance. Recently these techniques have been further developed and are now being used to provide surveillance within Approach, Terminal Maneuvering Areas and En-Route airspace. These systems are known as Wide Area Multilateration (WAM).

As WAM and ADS-B have many synergies, an integrated WAM/ADS-B system is being offered by industry and will become a key element in the future surveillance infrastructure.

The deployment of ADS-B and WAM supports the vision of a cost- and RF spectrum efficient, globally harmonised Surveillance infrastructure achieving the Safety, Performance and Interoperability requirements of the current and future ATM services.

Further information about WAM can be found in the library section and also in the CASCADE Programme website.

New Techniques

Increasingly stringent performance targets coupled with new operational requirements are emerging from Single European Sky and SESAR initiatives. Whilst these will certainly drive a number of changes to the existing surveillance infrastructure, the evolution will also be influenced by an extensive range of other factors which include global interoperability, civil-military co-ordination, transition issues, institutional issues, changing aircraft populations e.g. the introduction of Very Light Jets -  VLJs and Unmanned Airborne Systems – UASs, and business considerations. In addition cost and RF spectrum considerations are also increasingly key considerations.

Meeting these new requirements may necessitate changes to existing systems. Some of these requirements may only be met through emerging or even new technologies.

One technique that is under assessment is Multi-Static Primary Surveillance Radar (MSPSR). MSPSR is an independent non-cooperative civil and military Surveillance for Terminal Approach Control and en-route purposes. It is based on a sparse network of stations able to transmit and receive omni-directional C.W waveforms. (The results of studies into the subject can be found in the library section).

MSPSR is not alone in offering potential to improve the surveillance infrastructure - other techniques may offer improvements to the efficiency of 1030/1090 MHz transmissions. Others, such as Satellite ADS-B surveillance, may offer a means to provide surveillance in areas of the world where traditional techniques are not viable. EUROCAE WG-103 was recently established to develop a Technical Specification for Non-Cooperative Sensors that is technology independent and can support other emerging types of design of such sensors.

Products & Services

EUROCONTROL has developed a number of surveillance system constituents that are readily available to its Member States. These include ARTAS (ATM surveillance Tracker and Server), SASS‑C (Surveillance Analysis Support System for Centres) and Radar Message Conversion and Distribution Equipment (RMCDE) and Surveillance Data Distribution (SDD) systems.

ARTAS is the Eurocontrol state-of-the-art Surveillance Data Processing System. It is a system designed to combine sources of surveillance data to generate an accurate Air Situation Picture of all traffic over a well-defined geographical area. It also enables the distribution of the relevant surveillance information to a community of user systems.

SASS-C is a Surveillance Analysis toolbox that allows verification of the Surveillance infrastructure performance based on opportunity traffic in a multi-sensor environment. It is typically used for verification of the compliance of operational sensor and trackers to nominal performance, and in particular to those defined in the Eurocontrol Surveillance Standard for En-Route and Major TMAs.

RMCDE and SDDS are fully ASTERIX compatible Surveillance Data Distribution equipment used as an access node for Surveillance Networks (e.g. RADNET),

The development and evolution of these products address requirements stemming from European Air Navigation Service Providers (ANSPs). The centralised maintenance and support provides a cost beneficial mechanism to ensure that ANSPs across Europe can benefit from harmonised systems that are key to a safe and performant ATC infrastructure.

For further information you may consult the Support Services page.

Surveillance and Code Coordination (SCC) Unit

For further information on this subject please contact us.