DEVICE OF IDENTIFICATION AT SURFACE ACOUSTIC WAVES Russian patent published in 2008 - IPC G01S13/75 G01S13/76 H03H9/42 

FIELD: radio engineering.

SUBSTANCE: device consists of acoustic ducts for different acoustic channels, receiver-transmitter interdigital transducers (IDT) and reflecting IDT with the same period L_0i, which is different in different acoustic channels. Analogous electrodes of first additional IDT are connected with common bus bar through lower bus bars of receiver-transmitter IDT. Each of other electrodes of first additional IDT is connected with electrodes of second additional IDT with aperture, which is 10 times less. Other electrodes of second additional IDT are connected with antenna. Other end of antenna is connected with common bus bar, which connects analogous electrodes of receiver-transmitter IDT, which do not have galvanic connection with second additional IDT. Acoustic ducts together with IDT and common bus bar are installed in leak-tight casing.

EFFECT: increases reflection factor from reflecting IDT, which are located in different acoustic channels.

1 dwg