Contents I. Introduction
Pulsed power supplies are widely used when power consumption has an important impact on the feasibility of the application [1]; this is the case, among others, of pulsed lasers, electromagnetic pulse generators, or even particle accelerators [2]. In this framework, the full characterization of the power pulses is needed in order to, for instance, predict the exact amount of energy delivered to the load. The state of the art for pulse measurements is mostly dedicated to ultra-fast pulses in the nanosecond regime (or even sub-nanosecond) as highlighted by the National Institute of Standards and Technology (N1ST) [3]; in addition, the reference standard [4] is mostly (or entirely) dedicated at the evaluation of the pulse parameters, which are critical for many industrial fields as discussed in [5] and [6] where both procedures and definitions are given. However, new and more demanding applications arise from particle accelerators for high-energy physics. At CERN, a new linear accelerator is currently under study, the Compact LInear Collider (CLIC); its klystrons will be supplied by high-voltage modulators in pulsed mode. The required experimental precision is achieved by a careful characterization of the high-voltage pulses [7]. For this reason, an ultra-low noise acquisition system has been designed and developed at CERN [8]. In this paper, the preliminary metrological characterization of the above mentioned acquisition system, with special focus on the common mode rejection evaluation, is presented. In particular, the test setups and the obtained results are illustrated.
