Local, blind synchronization of Channel Impulse Responses for key generation algorithms without leaking details to adversaries is challenging, due to noise from transmission and measurements. Extracting the channel characteristics as a common source of randomness using CIR promises notable improvements in key bit rates for Physical Layer Security, however, reciprocity requirements necessitate successful synchronization at both ends. We propose a one-dimensional Gaussian filter towards this end, which is simple, more robust, and outperforms competing approaches in almost all settings. To evaluate the quality of our approach, we assess the synchronization accuracy on extensive datasets. Experiments using data generated synthetically with the standardized IEEE 802.15 UWB channel model indicate a performance improvement of up to 31%. Performance on par or better than all alternatives in real measurements underlines its superior robustness against synchronization errors.