FIPSER: Performance Study of a Readout Concept With Few Digitization Levels for Fast Signals

TL;DR

This paper evaluates FIPSER, a cost-effective readout system with few digitization levels for fast detector signals, demonstrating high resolution and pulse separation capabilities through simulations.

Contribution

It introduces FIPSER, a novel digitization approach using limited voltage levels, and shows its effectiveness in achieving high resolution with fewer resources.

Findings

Achieves amplitude resolution better than Poisson limit with 12 levels

Time resolution ranges from 0.02 to 0.16 FWHM depending on amplitude

Can separate consecutive pulses at minimal separation of 0.05-0.30 FWHM

Abstract

We discuss the performance of a readout system, Fixed Pulse Shape Efficient Readout (FIPSER), to digitize signals from detectors with a fixed pulse shape. In this study we are mainly interested in the readout of fast photon detectors like photomultipliers or Silicon photomultipliers. But the concept can be equally applied to the digitization of other detector signals. FIPSER is based on the flash analog to digital converter (FADC) concept, but has the potential to lower costs and power consumption by using an order of magnitude fewer discrete voltage levels. Performance is bolstered by combining the discretized signal with the knowledge of the underlying pulse shape. Simulated FIPSER data was reconstructed with two independent methods. One using a maximum likelihood method and the other using a modified chisquared test. Both methods show that utilizing 12 discrete voltage levels with a sampling rate of 4 samples per full width half maximum (FWHM) of the pulse achieves an amplitude resolution that is better than the Poisson limit for photon-counting experiments. The time resolution achieved in this configuration ranges between 0.02 - 0.16 FWHM and depends on the pulse amplitude. In a situation where the waveform is composed of two consecutive pulses the pulses can be separated if they are at least 0.05 - 0.30 FWHM apart with an amplitude resolution that is better than 20%.