Optimization-Based Behavioral Modeling of Mixers for Frequency Comb OFDM Radar Processing

Umut Utku Erdem; Henning Poensgen; Taewon Jeong; Lucas Giroto; Benjamin Nuss; Ibrahim Kagan Aksoyak; Ahmet Cagri Ulusoy; Thomas Zwick

arXiv · 2602.23889

Optimization-Based Behavioral Modeling of Mixers for Frequency Comb OFDM Radar Processing

Umut Utku Erdem·Henning Poensgen·Taewon Jeong·Lucas Giroto·Benjamin Nuss·Ibrahim Kagan Aksoyak·Ahmet Cagri Ulusoy·Thomas Zwick

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Abstract

This paper presents an optimization-based behavioral model for mixers driven by multi-tone local oscillator (LO) signals, considered specifically for frequency comb orthogonal frequency-division multiplexing radar applications. Unlike traditional models, the proposed approach is designed and tested for multi-tone LO excitations. The model uses polynomial nonlinearities for both intermediate frequency and LO ports, supported by spectrum-domain fitting that selectively emphasizes strong intermodulation products. In addition, a polynomial block is introduced to capture input power-dependent phase nonlinearity. The approach is validated using circuit-level simulations and supported by measurements. Radar processing results show the model replicates distortive effects in simulations. The proposed model enables rapid system-level performance estimations and waveform optimization, replacing computationally expensive circuit-level simulations.

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BibTeX RIS

Umut Utku Erdem, Henning Poensgen, Taewon Jeong, Lucas Giroto, Benjamin Nuss, Ibrahim Kagan Aksoyak, Ahmet Cagri Ulusoy, Thomas Zwick. 2026-02-27. Optimization-Based Behavioral Modeling of Mixers for Frequency Comb OFDM Radar Processing. https://arxiv.org/abs/2602.23889

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