Comparative Analysis of Mismatched Filtering Techniques: Cyclic vs. Non-Cyclic Approach

This work evaluates the performance of the Zadoff-Chu (ZC)-sequence using tapering, matched, and mismatched filtering techniques for the usecase of medical ultrasound imaging. Additionally, a novel approach is introduced that applies cyclic processing and transmission methods from mobile communications. Simulations were conducted to compare the cyclic and non-cyclic approaches, using the integrated-sidelobe-level (ISL) and signal-to-noise-ratio (SNR)-gain as performance metrics. The cyclic approach demonstrated superior ISL values and a modest SNR-gain improvement of approximately 2 dB compared to the non-cyclic method. While both approaches showed similar SNR-gains, the cyclic method achieved better ISL results without tapering, thus offering a better overall SNR-gain. Using the UlaOp ultrasound research platform, images were captured with both approaches. The reconstruction revealed significant crosstalk issues in the cyclic approach due to the simultaneous transmission and reception required, negatively impacting image quality and limiting its effectiveness. Future work should focus on mitigating crosstalk to fully harness the benefits of cyclic processing in ultrasound imaging applications.