Distributed Nonlinear Model and Fast Analysis for In-Band IMD3 Prediction of Surface Acoustic Wave Resonators

Area of Science:

• Electrical Engineering
• Acoustics
• Materials Science

Background:

• Surface Acoustic Wave (SAW) devices are crucial for wireless communication filters.
• Nonlinear effects, such as intermodulation distortion (IMD), degrade SAW device performance.
• Accurate and efficient analysis of IMD in SAW devices is challenging due to their distributed nonlinear nature.

Purpose of the Study:

• To analyze in-band intermodulation distortion (IMD) in SAW devices using a novel, fast computational method.
• To validate the accuracy of the Input-Output Equivalent Sources (IOES) method against established simulation techniques.
• To apply the IOES method for analyzing IMD3 in specific LSAW resonators for LTE applications.

Main Methods:

• Development and application of the Input-Output Equivalent Sources (IOES) method for nonlinear analysis.
• Validation of IOES accuracy by comparing results with Harmonic Balance (HB) simulations on a discretized Mason-based SAW resonator model.
• Simulation of measured in-band IMD3 for lithium tantalite leaky SAW (LSAW) resonators using the IOES method.

Main Results:

• The IOES method accurately predicts IMD in SAW devices, matching HB simulation results.
• IOES simulations are approximately 1000 times faster than commercial HB simulations.
• The IOES method successfully analyzed complex LSAW resonators for the B66 LTE band, a task intractable for conventional HB methods.

Conclusions:

• The IOES method offers a highly efficient and accurate approach for analyzing nonlinearities in SAW devices.
• This method significantly accelerates the design and optimization process for SAW filters, particularly for demanding applications like LTE.
• The IOES technique enables the simulation of large-scale distributed nonlinear problems in SAW devices that were previously computationally infeasible.