Built-in test equipment

With the abbreviation BITE (from English: Built In Test Equipment, Built-in test equipment ) is called hardware and software in a computer system that makes it easier to check the correct functioning of the system and to monitor and automatically, if necessary, allows it to respond to problems. Such test facilities are such as integrated in safety-critical systems in the avionics.

Example radar system

A radar system the transmitter must not be switched on when the test circuits of the antenna to report a malfunction. If the transmitter is operating, a part of transmission power is output via the directional coupler, in the same direction and the amplitude of this signal is measured by comparators and sends the value to the radar data processor. Similarly, all operating voltages and clock pulses for the radar device to be monitored.

During operation of the radar unit are fed to the dead by the Radar Data Processor test signals into the antenna through the entire signal processing path from the antenna to the display unit, and whose presence and whose size is at intermediate points, for example, examined how the receiver output.

Upon detection of a faulty module or a missing signal, this information is displayed to the operator on the radar screen. Some radars can even automatically reconfigure the system to enable the defect despite a continuing work in the core tasks. This requires, however, the presence of a plurality of parallel processing channels target (redundancy), one of which can be switched off with a lower importance of the radar data processor and the intact modules can then be connected as a replacement in the more important data channel.

For example, radar devices that operate according to the monopulse method, four identical receiving channels, one of which is used to suppress the side lobes of the antenna. This channel is then used by the Radar Data Processor as a supplier of redundant modules. A sidelobe suppression is then no longer possible.

• Radar module