MX12B aviation surveillance device

The MX12B is a micro transponder from Sagetech, an ADS-B transponder for unmanned aircraft and other platforms where weight and space are tight. It provides the 1090 MHz extended squitter datalink, so it identifies the aircraft to air traffic surveillance and also receives the traffic of other aircraft.

Its published mass is 190 g, and the operating temperature range is -40 to 71 °C. The mass is small enough for small and medium unmanned aircraft, and the temperature span covers high-altitude cold and hot soak on the ground. The maker lists the size as roughly 3.4 inches high, 2.5 inches wide and 1.0 inch deep. The unit combines the Mode S transponder function with ADS-B Out and ADS-B In, so one box covers both transmitting identification and position and receiving traffic information. The maker also lists a Mode 5 IFF capability for military operation.

An integrated pressure-altitude encoder provides the altitude source, so the integrator does not need a separate encoder for the altitude report. Antenna diversity is supported, which allows two antennas to be connected so that the unit can use the one with the better signal in flight, a useful feature on aircraft where the airframe may shadow a single antenna.

For integration, the physical interfaces are Ethernet, RS-422 and RS-232. These let the transponder be connected to a flight controller, a mission computer or a ground control link, which can supply position data, set the transponder code and read traffic. The installation also needs the antenna or antennas and a position source, as the transponder forms part of a larger surveillance installation.

Typical applications are surveillance and cooperative detection for unmanned aircraft in shared airspace, defence unmanned systems that need Mode 5 IFF, and eVTOL and large-drone programmes that require a light transponder with traffic reception.