CNS Services
We offer Communication, Navigation, and Surveillance (CNS) assessments for airport development, including terminal buildings, hangars, and construction cranes. Our assessment depends on the facilities affected, but may include the ILS system (localizer and glidepath), radar systems (ASR, SMR, SSR), microwave links, and voice transmitters/receivers. Off-airport developments such as tall buildings, towers, or wind farms need to be assessed against their impact on VORs (Doppler and conventional), NDBs, DME stations, or en-route radars. We will not only calculate the effect of your development project but also help you choose special measures that may need to be taken to alleviate problem areas.
Our methods are state of the art: We do a full 3D assessment, apply method-of-moments techniques for calculating indirect fields (whenever accuracy matters), and provide you with convenient and easy-to-understand geo-referenced results you can use to supplement your building permit applications.
What is CNS Safeguarding?
Communication, Navigation, and Surveillance (CNS) Safeguarding is an assessment method used in aviation. Its purpose is to ensure that new buildings, construction, or towers do not degrade the performance of (navigation, radar) systems used in aviation. Under CNS systems, basically all radio (EM-transmission) based aviation infrastructure is summarized. These are, for example, radio transmitter/receiver antennas to provide voice communication to airplanes, conventional radio navigation aids (like VOR, NDB, ILS, DME) that help an aircraft determine its position, and radar stations (both primary and secondary) that give position information to the ATC service provider (ANSP).
Radio-based systems are vulnerable to signal-in-space disturbances caused by physical obstacles such as buildings, cranes, wind turbines, or other high towers. Dynamic objects (moving planes, trucks, wind turbines) can also be a factor. As the quality of the signals is usually defined by ICAO requirements, building-restricted areas (BRA) are usually defined around transmitter stations where the impact of new construction has to be assessed in order to ensure that the signal-in-space disturbances it causes do not dilute signal quality beyond the acceptable limit defined by the requirements set in ICAO Annex 10 (and amended by national requirements of the ANSP).
Sometimes the building restricted areas are very limiting and, depending on the facility affected, may lead to conflicts between developers and airspace users. However, in many cases, technical solutions can mitigate adverse impacts.