Software defined radios for ATC communications

Software defined ATC radiosThe R&S®Series4200 is our most recent generation of digital, software defined radios for civil air traffic control in the VHF band and for military air traffic control in the UHF band. The radios are capable of handling voice communications between air traffic controllers and pilots throughout every phase of a flight. The air traffic controllers are connected to the radio stations sited at airports and at remote locations over a VCS – a setup that enables comprehensive, nationwide radio coverage encompassing all flight levels.

Exceptional reliability and low operating costs are the most important requirements to be met by radiocommunications systems. The outstanding RF characteristics of the R&S®Series4200 allow a large number of radios to be concentrated at a single location. Rohde&Schwarz can supply complete systems for radio sites, including antennas, filters, couplers and racks.

R&S®Series4200 radios are also ideal for airport apron communications. Their compact size means that they are easy to install in spite of the often cramped conditions in control towers. Plus, their ability to be operated locally as well as via a remote control unit makes them ideal for use in small-scale systems, which generally do not require a complex VCS.


More than 200 airports and control centers rely on our ATC communications systems.


Subsidiaries and offices in more than 70 countries provide local, on-site customer-care.


Civil air traffic control agencies in 80 countries count on our communications systems.

Detection of simultaneous radio transmissions

Air traffic density has risen significantly in the last 20 years. Greater demands on airspace capacity means increased safety risks such as undetected simultaneous transmissions (USiT). If two pilots speak at the same time to the controller, there is a danger that the weaker signal will go undetected, leading to a loss of information.

Rohde & Schwarz has developed an innovative solution to this long-standing problem. The receiver-based digital signal processing of the stationary R&S®Series4200 VHF/UHF radios makes it possible to detect multiple parallel radio transmissions. Rohde & Schwarz is the first supplier to offer detection of simultaneous transmissions (DSiT) in its ATC radios.