Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > T&M

RF test set rolls for aircraft radio altimeters

Posted: 29 Mar 2010 ?? ?Print Version ?Bookmark and Share

Keywords:RF test set? radio altimeter? simulator? avionics market?

ALT-8000 RF test set

Aeroflex has launched the ALT-8000 RF-based portable radio altimeter flightline test set. The ALT-8000 is a lightweight universal test set for 4.3GHz FMCW (frequency-modulated continuous carrier wave) radio altimeters and pulse radio altimeters with a large 12-inch color touchscreen for ease of use.

The ALT-8000 is an inexpensive, portable simulator for testing radio altimeters installed in aircraft and unmanned aerial vehicles (UAV). Until now, flightline test sets have not been RF-based and have only tested the analog or digital back-end of the receiver via test port signal injection. Existing RF-based test systems have been confined to bench test applications and rely upon heavy, bulky and expensive delay lines to check altitude indications at one or two fixed points.

By contrast, the ALT-8000 is easy to use and can be carried to the flightline. The ALT-8000 may be directly coupled to the radio altimeter transmitter/receiver (TX/RX) ports or may be connected via supplied TX/RX antenna couplers, which accommodate most aircraft antenna variants. As a result, faulty radio altimeter system elements can be identified faster. Problems are identified with a positive diagnosis and a confirmed resolution, reducing NFF (no fault found) occurrences and reducing the airline LRUs (line replaceable units) inventory.

RF simulation of radio altitude from -100 feet to +50,000 feet (1.5 foot accuracy) is provided and altitude rate may be set to provide a smooth ramping altitude simulation to verify decision heights and altitude trips, for auto-land systems and altitude data feed to EGPWS (enhanced ground proximity warning systems). Up to three ALT-8000 test sets may be linked via an altitude sync line for executing 2- or 3-channel coordinated altitude simulation for dual or triple installation auto-land system testing. The supplied antenna couplers allow the radio altitude system to be quickly verified, without access being required to test ports on the UUT (unit under test). The RF looped test verifies TX frequency, power, sweep rate; the RF level control provides the means to test the UUT sensitivity.

The ALT-8000 features testing capability for 4.3GHz FMCW radio altimeters, including CDF (Constant Difference Frequency) types, a universal test set for all system variants, ARINC-552 or ARINC-707, or custom. It also handles 4.3GHz (non-pulse compression) pulse radio altimeters. In addition, the ALT-8000 includes full RF loop test that allows TX antenna or feeder faults to be identified by measuring TX power and frequency and sweep rate. Programmable multi-leg climb and descend profiles to test auto-land systems with programmable, repeatable approach flare profile. The devices also pack altitude path loss simulation to ensure that the test environment replicates actual airborne conditions, allowing antenna bonding issues to be verified and test RX sensitivity.

The Aeroflex ALT-8000 radio altimeter is available in 16 weeks upon receipt of order.

Article Comments - RF test set rolls for aircraft radio...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top