On-Line Measurement of the Tip Clearance and Time of Arrival of a Bladed Disk of an Aircraft Engine
Safety and performance of the turbo-engine in an aircraft is directly affected by the health of its blades. In recent years, several improvements to the sensors have taken place to monitor the blades in a non-intrusive way.
Tip clearance - distance between the blade tip and the casing
Time of Arrival (ToA) - passing time at a known position of two consecutive blades
Software-defined radio (SDR) is a radio communication system where components that have been traditionally implemented in hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a personal computer or embedded system.
A basic SDR system may consist of a personal computer running SDR software that interfaces with analog-to-digital converter over USB or ethernet, preceded by some form of RF front end with RF amplifiers, filters and attenuators.