Date: 07/08/2009

Rohde & Schwarz adds DME options for aeronautical radio navigation services

Rohde & Schwarz adds new options for aeronautical radio navigation systems to test distance measurement equipment (DME) with better flexibility and precision. The R&S SMA100A analog signal generator, generates and analyze DME signals in both the lab and in mobile applications.

The compact R&S EVS300 ILS/VOR analyzer has been enhanced to include the ability to analyze DME signals, ideal for mobile maintenance of DME ground stations. Options for measurements on ILS and VOR services are available for checking the key functions of their systems in accordance with the specifications of the International Civil Aviation Organization (ICAO).

An aircraft uses DME to measure its slant distance to a ground station. To make this measurement, the aircraft’s onboard radio unit (interrogator) transmits shaped RF double pulses to the ground station, which returns them after a defined delay (reply delay). If there any fault in the equipment could lead to incorrect measurement results or even malfunctioning of the system. The use of external measuring equipment therefore increases air traffic safety.

The new R&S EVS-K5 option allows users to perform power measurements on DME and ILS/VOR ground stations. The only user action required is to connect the power sensors of the R&S NRP or R&S NRT family to the analyzer. Using the new R&S EVS-K6 option, the R&S EVS300 can also check the envelope and timing of the double pulse transmitted to DME ground stations. The combination of the R&S NRP-Z81 broadband power sensor and the new option enables to view the rise time, fall time and pulse spacing of the DME signal directly on the analyzer’s display.

When equipped with the R&S SMA-K26 option, the R&S SMA100A generates DME aircraft interrogator signals and also simulate a DME ground station including the squitter and identification pulses. Using a connected R&S NRP-Z81 broadband power sensor, the parameters specified by the ICAO can be analyzed directly on site at a ground station. The DME test parameters include, reply delay, reply efficiency (ratio of reply pulses to interrogation pulses), pulse repetition rate of the ground station, pulse power of the transmit pulse and pulse shape. For test purposes, the parameters can be set so that they deviate from the ICAO specification.

The DME options (R&S EVS-K6 for the R&S EVS300 and R&S SMA-K26 for the R&S SMA100A) are now available.

For more details visit http://www.rohde-schwarz.com/