Design of digital correlation systems for low-intensity precision photon spectroscopic measurements

Architectures and design considerations for correlators to be used in singl e photon spectroscopy with a large spread of time offsets (lag times) are i nvestigated. An extraordinary dynamic range of 10(12) is achieved by using the multiple sampling time architecture, where the sampling time is increas ed systematically for larger correlation time intervals. Short sampling tim es below 10ns, important for the analysis of fast processes. are achieved b y partitioning of the system into a fast semi-custom ASIC and an off the sh elf digital signal processor (DSP). Accuracy aspects and normalisation issu es of correlator architectures are discussed and performance and hardware e fficiency are compared to existing solutions.