Methodology and Measurement Setup for Analog-to-Digital Converter Post-Compensation

C. SCHMIDT; O. LIFSCHITZ; J. E. COUSSEAU; J. L. FIGUEROA; P. JULIAN

IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2014

0018-9456

We present a methodology for nonlinearity compensation amenable to a wide variety of analog-to-digital converters (ADCs). To that purpose, a post-compensation scheme for a commercial ADC is presented and two compensator models are considered: the memory polynomial and the modified generalized memory polynomial. Since the proposed method does not use any information about the compensated architecture it can be applied to different ADC designs. Furthermore, we address the measurement and characterization setup of the device under test by making a study of the quality of the signals involved to verify the improvement obtained. The issue of the training sequences required by the proposed compensation method is also addressed in detail. Despite the common use of a single training signal, we propose to use several sinusoids in the bandwidth of interest. Based on this it is possible to show that the generalization properties of the estimated postcompensator are greatly enhanced compared to the case of a single sinusoid training sequence. As verified by measurements, considerable gain in accuracy can be obtained using the proposed methodology. In particular, a 10 dB increment in SFDR is obtained using the proposed post-compensators over the complete Nyquist frequency band.