U.S.A. as represented by the Administrator of the National Aeronautics and Space Administration
发明人:
William T. Yost,John H. Cantrell,Daniel F. Perey
申请号：
US15065089
公开号：
US20160262621A1
申请日:
2016.03.09
申请国别(地区):
US
年份:
2016
代理人:
摘要：
Systems and methods for measuring phase dynamics and other properties (e.g. intracranial pressure) are disclosed. For example, the system may generate a reference waveform and a measurement waveform using digital synthesizers, each waveform having an identical constant frequency but also a relative phase shift. Next, system may send a tone-burst, via a transducer, into a sample (e.g. a skull or a bonded material), and then receive a reflected tone-burst in response. Then, a phase difference between the received tone-burst and the measurement waveform may be determined with a linear phase detector. Next, the phase shift of the measurement waveform may be adjusted, by the determined phase difference, such that there is no longer any phase difference between the received tone-burst and the adjusted measurement waveform generated by the appropriate digital synthesizer. A similar adjustment may occur after subsequent tone-bursts, allowing accurate monitoring of continuously variable phase relationships.
