DUPLEX ULTRASOUND SYSTEM FOR COMMUNICATION AND ENERGY TRANSMISSION THROUGH WALL WITH FREQUENCE TRACKING

摘要

A method and an apparatus providing synchronous two-way communication of information with passing barrier by means of piezoelectric transducers pair are disclosed. Transferred from barrier outer side to inside thereof the differentially encoded binary data sample is executed only on inner side, when repeated known bit in Barker sequence is transmitted to opposite direction. Differentially encoded data are transmitted on the base of absolute value difference between each and previous signal envelope samples. Data from inner- to outer side are transmitted by changing electrical load on internal inverter, as a result of which, reflection continuous wave signal proportion is changed. Electrical impedance is changed by continuous wave reflected part, and the change is measured and interpreted as binary data. Transmit power minimal sufficient, at first, and then – optimal frequency and data are sampled with stepwise frequency change process by means of two algorithms sampling frequency.