Double-Mode Surface-Acoustic-Wave (DMS) Filter with Apodization

An apparatus comprising:

• a double-mode surface-acoustic-wave filter comprising multiple interdigital transducers, the multiple interdigital transducers comprising multiple fingers, the multiple fingers having various lengths to form an apodized structure across at least part of the double-mode surface-acoustic-wave filter, the multiple interdigital transducers comprising:
• a first interdigital transducer comprising a first portion of the apodized structure, the first portion comprising one or more first apodization properties;
• a second interdigital transducer comprising a second portion of the apodized structure, the second portion comprising one or more second apodization properties different from the one or more first apodization properties;
• and
• a transition region overlaying a border between the first interdigital transducer and the second interdigital transducer, the transition region comprising a transition portion of the apodized structure, the transition portion including a phase shift of the apodized structure.

A method of manufacturing a double-mode surface-acoustic-wave filter, the method comprising:

• providing multiple interdigital transducers comprising multiple fingers, an overlap region of fingers extending from opposite busbars establishing an aperture of the double-mode surface-acoustic-wave filter, the aperture forming an apodized structure across at least part of the double-mode surface-acoustic-wave filter;
• providing a first portion of the apodized structure using a first interdigital transducer of the multiple interdigital transducers, the first portion comprising one or more first apodization properties;
• providing a second portion of the apodized structure using a second interdigital transducer of the multiple interdigital transducers, the second portion comprising one or more second apodization properties different from the one or more first apodization properties of the first interdigital transducer;
• and
• providing a transition portion of the apodized structure, the transition portion overlaying a border between the first interdigital transducer and the second interdigital transducer, the transition portion having a non-vanishing slope.