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arXiv · 2603.05127

A Fully Open-source Implementation of an Analog 8-PAM Demapper for High-speed Communications

Mohamed Aiham Hemza·Alex Alvarado·Krzysztof Herman·Piyush Kaul
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Abstract

Spectrally-efficient communication systems rely on the use of multi-level modulation formats. At the receiver side, a demodulator is often used to extract soft information about the transmitted bits. Such a demodulator is typically implemented in the digital domain. However, analog implementations of such demodulators are also possible. In this paper, we design and simulate an analog 8-ary pulse-amplitude modulation (8-PAM) demapper in IHP SG13G2 SiGe BiCMOS technology. We generalize and improve a design available in the literature for 4-PAM. A fully MOSFET-based 8-PAM design is proposed. Our simulations and design are completely based on open-source IC design tools. Our results show an energy efficiency of 0.33 pJ/bit for a data rate of 1Gbit/s.

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Mohamed Aiham Hemza, Alex Alvarado, Krzysztof Herman, Piyush Kaul. 2026-03-05. A Fully Open-source Implementation of an Analog 8-PAM Demapper for High-speed Communications. https://arxiv.org/abs/2603.05127

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