General Analysis of Resolution Enhancement on Time Synchronized Sampling and its Multi Resolution Solution in 20GSPS Acquisition System
Multiple resolutions have become a new feature required in ultra fast data acquisition systems (UF DASs) for various high end applications, especially for large scale physical experiments and radar equipment. However, plenty of repetitive efforts are paid to build various UF DASs with different resolutions for many similar purposes. In this paper, a system level sampling solution featuring multi resolution is explored for UF DASs to make the trade off between accuracy and speed. Firstly, a resolution enhancement mechanism based on a time synchronized sampling technique is studied more generally with probabilistic and statistical theory, and its applicable premise is discussed quantificationally at the same time. Then, a hardware based reconfigurable structure for the purpose of multi resolution high speed sampling is discussed with the combination of time interleaved and time synchronized sampling methods. Furthermore, to verify the proposed theory, a prototype with a maximal 20GSPS sampling rate and different resolutions of 8,9,10 bit is established. The experimental results show that three vertical resolutions of 8, 9 and 10 bit are achieved in the same prototype, and the effective number of bit (ENOB) in the two higher resolution modes has been improved remarkably from a single low resolution analog to digital converter (ADC) Therefore, the proposed theory and multi resolution sampling solution are important guides to the resolution trade off requirement in ultra fast acquisition systems.
IEEE Access