Remote acoustic powering and data transmission for sensors inside of conductive envelopes

In modern aeronautics and aerospace industry there is a great demand for wireless sensors in order to improve efficiency, reliability and to reduce the costs. They are the key enablers for improved system concepts like e.g. condition based maintenance. In some cases, sensors need to be placed in closed conductive envelopes like hydraulic accumulators, oxygen bottles, etc., where battery usage may be not allowed or not possible due to maintenance requirements and where classical wireless radio frequency communication is not applicable due to strong shielding effects. For this field of applications, a solution has been developed that uses ultrasonic acoustic waves for a wireless transmission of energy and data through the envelope walls. The main benefit of this technology is that the envelope remains unaffected and therefore the hermeticity and structural integrity are retained. Moreover the sensor can be chosen almost independently from the communication and power transmission system.