Experimental and theoretical results of new unidirectional interdigital transducers using floating electrodes

We propose the new configurations of the internal reflection type of unidirectional IDT with the high transduction using high coupling substrates of 128° YX LiNbO
₃
[1], 36° YX LiTaO
₃
[2] and SiO
₂
/YX-LiNbO
₃
[3] with k
²
=0.3 and zero Temperature Coefficient of Frequency (TCF). The theoretical and experimental results showed the good directivities. Moreover we describe weighting method for the FEUDT filters.