Analog Integrated Circuits and Signal Processing

, Volume 39, Issue 3, pp 251–266

High Precision Image Centroid Computation via an Adaptive K-Winner-Take-all Circuit in Conjunction with a Dynamic Element Matching Algorithm for Star Tracking Applications


  • Alexander Fish
    • The VLSI Systems CenterBen-Gurion University
  • Dmitry Akselrod
    • Motorola Semiconductor
  • Orly Yadid-Pecht
    • The VLSI Systems CenterBen-Gurion University

DOI: 10.1023/B:ALOG.0000029661.59987.3c

Cite this article as:
Fish, A., Akselrod, D. & Yadid-Pecht, O. Analog Integrated Circuits and Signal Processing (2004) 39: 251. doi:10.1023/B:ALOG.0000029661.59987.3c


An approach for implementing a high precision image target centroid—center of mass (COM) detection system via an adaptive K-winner-take-all (WTA) circuit in conjunction with a 2-D dynamic element matching (DEM) algorithm implementation for image sensor arrays is proposed. The proposed system outputs a high precision COM location of the most salient target in a programmable active region of the field of view (FOV) for star tracking purposes and is suitable for real time applications. The system allows target selection and locking with multiple targets tracking capability. This solution utilizes the separability property of the COM, and therefore reduces the computational complexity by utilizing 1-D circuits for the computation. The DEM algorithm, commonly used in ADC and DAC circuits, allows reducing the required WTA circuit precision to 5–6 bits, while still achieving a high output precision. Simulation results prove the concept and demonstrate the high precision COM result. In addition, a possible low-level hardware implementation is described.

APSCMOS imagercenter of massCOMcentroidK-WTA circuitK-Winner-take-all circuitdynamic element matchingDEMstar-trackingimage processing

Copyright information

© Kluwer Academic Publishers 2004