High loop-filter-order ΣΔ-fractional-n frequency synthesizers for use in frequency-hopping-spread-spectrum communication-systems. - Niels Christoffers; Rainer Kokozinski; Stephan Kolnsberg; Bedrich J. Hosticka (ISCAS (2), 2003)

Performance of compensation algorithms for direct-conversion receivers under finite wordlength constraints. - Rolf Weber 001; Markus Jordan; Niels Christoffers; Hans-Christian Müller (PIMRC, 2005)

A 4-bit RFDAC-Based FMCW Modulator for Automotive Radar. - Soumya Krishnapuram Sireesh; Niels Christoffers; Sanaz Hadipour Abkenar; Christoph Wagner; Andreas Stelzer (IEEE J. Solid State Circuits, 2025)