System Description

System Description and Installation Manual for MXS ICD10004-01
© Sagetech Corporation 2018 Confidential Proprietary Export-Controlled Page 8 of 160
Overview
The MXS transponder performs the following basic functions:
 Transponder:
o Interacts with air traffic control (ATC) by transmitting and receiving standard secondary surveillance
radar pulses per ICAO requirements. The transponder replies to ATCRBS interrogations with a squawk
code and pressure altitude data.
o Provides Mode S replies (includes data such as ICAO address and call sign) and is capable of being
selectively interrogated.
 ADS-B In:
o The MXS receives Automatic Dependent Surveillance-Broadcast (ADS-B) In Extended Squitter
messages (ES) that have been transmitted automatically from surrounding planes and the Air Traffic
Control (ATC) system.
o ES messages report Position, Velocity, Identification and Category, Target State and Status, and
Aircraft Operational Status. From this data, MXS generates ADS-B, TIS-B and ADS-R reports for
delivery to the flight computer which communicates the data to the user.
o Transponders with ADS-B In are useful for sense and avoid applications by providing the user with
surrounding traffic information with a nominal range of 120 nautical miles (NM).
 ADS-B Out:
o Provides host computer-controlled Automatic Dependent Surveillance-Broadcast (ADS-B) Out
capability.
o Transmits Extended Squitter (ES) and Acquisition Squitter messages at regular intervals, providing
Position, Velocity, Identification and Category, Emergency/Priority Status, Target State and Status,
Aircraft Operational Status, and other aircraft data.
 Altitude data for the ES can be based on the MXS’s integrated altitude encoder, or one
provided external to the MXS.
 GPS data, also included in the ES, is provided to the MXS from the avionics system integrator.
 Receives Installation, Flight ID, Operational and GNSS navigation data from Host Computer
or directly from sensors.
 Altitude Encoder:
o Computes own-ship barometric altitude with integral, calibrated pressure sensor and encoder (termed a
blind encoder).
The MXS accomplishes these functions by communicating with ATC, surrounding aircraft, the aircraft flight computer,
external GPS, and discrete inputs from the aircraft.
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SpecificaspectsoftheMXStransponderincludethefollowing:
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 GPS input is accepted from the following sources: via the host interface command link, or via NMEA or Accord
serial formats over dedicated pins on the host connector.

MXS supports antenna diversity.
 Two Transponder/ADS-B L-Band antennas are used.
 MXS includes an internal pressure altitude sensor, encoder and an altitude encoder port to a static pressure line.
The integral altitude encoder is calibrated to 85,000 feet MSL by default. Configurations are available with
calibration/defined altitude error up to 100,000 feet MSL.
 Its approximate dimensions are 3.3” x 2.4” x 0.9”. (See Figure 0-1Figure 4-1.)
 Operating temperature is designed to be -40 to +71°C when 2.0°C/Watt of cooling is provided. Storage
temperature is expected to be -55 to +85°C.
 Input supply voltage range is 14-28 VDC +/- 4 VDC.