Search

The main factors that enable capture of complex and transient signals in real-time are improved sampling rates and processing speeds. The time-interleaved architecture is an effective method that allows systems to break through the speed bottleneck of single analog-to-digital converters (ADCs) and go beyond the state-of-the-art process technology limit. However, the performance of the acquisition system may be reduced because of the offset, gain, and time mismatch errors that occur in time-interleaved ADC systems. To correct these errors, this paper first proposes a self-adaptive correction algorithm and then introduces real-time solutions for this algorithm. Finally, the proposed calibration method is implemented in a digital phosphor oscilloscope. Simulations and experimental testing indicate that this system shows good real-time performance and provides a high dynamic performance with an effective number of bits of 7.3 bits and a signal-to-noise ratio of 45.5574 dB. [ABSTRACT FROM AUTHOR]

Because of the exponential increase of sampling rate, time-interleaved analog-to-digital converter (TIADC) has a fast growth in the high-speed applications. However, the channel mismatch error is a serious challenge for the performance of TIADC. In this article, we address the timing skew mismatch error and propose a novel adaptive calibration method. The principle and operating process of the calibration algorithm are explained. To validate the proposed technique, we designed a four-channel TIADC-based digital oscilloscope with a sampling rate of 10 GS/s. Based on this instrumentation platform, (i) calibration algorithm was implemented by hardware; and (ii) a test platform consisting of advanced instruments and tools was setup to testify the effect and robustness of proposed algorithm. Moreover, the technical details of instrumentation are described for the first time. The experimental results show that the calibration algorithm significantly suppresses the distortions due to timing skew mismatch error. The TIADC-based instrumentation achieves spurious-free dynamic range of 52.48 dB and effective number of bits of 5.83 bit, respectively. Besides, the complexity of the proposed algorithm is compared and discussed. [ABSTRACT FROM AUTHOR]

Publisher's Note: "An adaptive calibration technique of timing skew mismatch in time-interleaved analog-to-digital converters" [Rev. Sci. Instrum. The initially-published version incorrectly identified the university of first affiliation, the "University of Electronic Science and Technology of China", as the "University of Science and Technology of China", which is a different institution. All online versions of the article were corrected on 21 November 2019. [Extracted from the article]

DC offsets in a quadrature mixing structure will affect the system performance. This paper proposes a Hilbert transform-based algorithm to blindly calibrate the DC offsets by filtering the inphase and quadrature signals with the same Hilbert filters. Compared with the traditional averaging-based method, this method consumes less time and resources. Moreover, the proposed method need not interrupt analog-to-digital converter's conversion, featuring the characteristics of high efficiency and good real-time performance. The Matlab simulation results verify the correctness of the proposed algorithm, and finally, an experimental platform is designed in detail to verify the practicability of this blind calibration algorithm. [ABSTRACT FROM AUTHOR]