Design of Two-Track Surface Acoustic Wave Filters with Width-Controlled Reflectors

Design of IF Two-Track Surface Acoustic Wave Filters Using (100) AlN/Diamond Structures

“…With given those COM parameters, reflection and transmission characteristics of reflection gratings and two-track SAW filters are calculated using the transmission matrix method. [5,6] Detailed information of the transmission matrix and the associated procedure for the calculation of the S-parameters of the two-track SAW filter can be found in references. [3,5,6] …”

“…The detailed information about the two-track SAW filters can be found in elsewhere. [5] For a uniform reflector, the reflection characteristics, 3 dB bandwidth and sidelobe suppression are not sufficient to be employed for designing a CDMA IF filter. To overcome this problem, some researchers employed the window function to modify the reflectivity or line width distributions of reflectors to gain an improved suppression capability.…”

“…The transmission matrix method is then applied to evaluate frequency responses of SAW filters. [5,6] …”

Design of IF two-track filters using IDT/(100) AlN/diamond structure

“…In this study, twotrack SAW filters are proposed for CDMA IF filters due to its no triple-transit influence (TTI) properties. The detailed information about the two-track SAW filters was presented in elsewhere [5]. In the two-track SAW filters, the input interdigital transducers (IDTs) are out of phase while output IDTs are in phase therefore the forward signals will eliminate; in other words, the TTI effect can be diminished.…”

“…For a uniform reflector, its reflection characteristics, 5dB bandwidth and sidelobe suppression cannot meet the specifications for the CMDA IF filter. To overcome this problem, some researchers employed different window functions to modify the reflectivity or line width distributions of reflectors to design IF filters [5][6][7].…”