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    Statistical performance analysis of MDL source enumeration in array processing

    , Article IEEE Transactions on Signal Processing ; Volume 58, Issue 1 , 2010 , Pages 452-457 ; 1053587X (ISSN) Haddadi, F ; Malek Mohammadi, M ; Nayebi, M. M ; Aref, M. R ; Sharif University of Technology
    Abstract
    In this correspondence, we focus on the performance analysis of the widely-used minimum description length (MDL) source enumeration technique in array processing. Unfortunately, available theoretical analysis exhibit deviation from the simulation results. We present an accurate and insightful performance analysis for the probability of missed detection.We also show that the statistical performance of the MDL is approximately the same under both deterministic and stochastic signal models. Simulation results show the superiority of the proposed analysis over available results  

    A Q-enhanced biquadratic Gm-C filter for High Frequency applications

    , Article ICECS 2006 - 13th IEEE International Conference on Electronics, Circuits and Systems, Nice, 10 December 2006 through 13 December 2006 ; 2006 , Pages 248-251 ; 1424403952 (ISBN); 9781424403950 (ISBN) Moezzi, M ; Zanbaghi, R ; Atarodi, M ; Tajalli, A ; Sharif University of Technology
    2006
    Abstract
    The design of a Gm-C filter for High-Frequency applications is described in this paper. A low-pass, sixth-order elliptic Gm-C filter based on the new biquadratic architecture in 0.18 um CMOS process is designed with the proper dynamic rang. A simple structure of the high Q biquadratic filter is used to enhance the linearity and tunability of the filter. The cut off frequency of this filter is 33 MHz. It has a THD of -45 dB for 0.2 Vpp, 8 MHz signal. The complete filter including on-chip tuning circuit consumes only 0.8mA with 1.8 V single supply voltage. ©2006 IEEE  

    Nonlinear ultrasound propagation through layered liquid and tissue-equivalent media: Computational and experimental results at high frequency

    , Article Physics in Medicine and Biology ; Volume 51, Issue 22 , 2006 , Pages 5809-5824 ; 00319155 (ISSN) Williams, R ; Cherin, E ; Lam, T. Y. J ; Tavakkoli, J ; Zemp, R. J ; Foster, F. S ; Sharif University of Technology
    2006
    Abstract
    Nonlinear propagation has been demonstrated to have a significant impact on ultrasound imaging. An efficient computational algorithm is presented to simulate nonlinear ultrasound propagation through layered liquid and tissue-equivalent media. Results are compared with hydrophone measurements. This study was undertaken to investigate the role of nonlinear propagation in high frequency ultrasound micro-imaging. The acoustic field of a focused transducer (20 MHz centre frequency, f-number 2.5) was simulated for layered media consisting of water and tissue-mimicking phantom, for several wide-bandwidth source pulses. The simulation model accounted for the effects of diffraction, attenuation and...