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Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Reconstruction of Nonuniformly Sampled Bandlimited Signals by Means of Time-Varying Discrete-Time FIR Filters | Hindawi Publishing Corporation EURASIP Journal on Applied Signal Processing Volume 2006 Article ID 64185 Pages 1-18 DOI 10.1155 ASP 2006 64185 Reconstruction of Nonuniformly Sampled Bandlimited Signals by Means of Time-Varying Discrete-Time FIR Filters Hakan Johansson and Per Lowenborg Electronics Systems of the Department of Electrical Engineering Linkoping University 58183 Linkoping Sweden Received 1 September 2004 Revised 20 December 2004 Accepted 6 January 2005 This paper deals with reconstruction of nonuniformly sampled bandlimited continuous-time signals using time-varying discretetime finite-length impulse response FIR filters. The main theme of the paper is to show how a slight oversampling should be utilized for designing the reconstruction filters in a proper manner. Based on a time-frequency function it is shown that the reconstruction problem can be posed as one that resembles an ordinary filter design problem both for deterministic signals and random processes. From this fact an analytic least-square design technique is then derived. Furthermore for an important special case corresponding to periodic nonuniform sampling it is shown that the reconstruction problem alternatively can be posed as a filter bank design problem thus with requirements on a distortion transfer function and a number of aliasing transfer functions. This eases the design and offers alternative practical design methods as discussed in the paper. Several design examples are included that illustrate the benefits of the proposed design techniques over previously existing techniques. Copyright 2006 Hindawi Publishing Corporation. All rights reserved. 1. INTRODUCTION Nonuniform sampling occurs in many practical applications either intentionally or unintentionally 1 . An example of intentional nonuniform sampling is found in analog-to-digital conversion where certain time slots are used for calibration and so forth. This can be viewed as if some samples from a uniform grid are discarded
