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Design and Implementation of Amplitude Detection Method for Millimeter Wave Imaging
, M.Sc. Thesis Sharif University of Technology ; Khavasi, Amin (Supervisor) ; Fakharzadeh, Mohammad (Co-Supervisor)
Abstract
Conventional imaging systems composed of two linear arrays of antennas as a transmitter and receiver. These arrays of antennas electronically scan along their antenna elements and are mechanically moved along a second orthogonal direction for scanning large two-dimensional areas quickly. In this thesis, the transmitter antenna elements are Tapered slot-line Antenna operating at 20-30GHz. A multiplexer circuit is used to transmit wideband signals to each antenna in the array. The receiver is composed of Schottky diode and pick up antenna that they are printed onto the radiating end of the antennas on the edge of the transmitter circuit board.In the available imaging systems, for achieving the...
K-Space analysis of aliasing in millimeter-wave imaging systems
, Article IEEE Transactions on Microwave Theory and Techniques ; Volume 69, Issue 3 , 2021 , Pages 1965-1973 ; 00189480 (ISSN) ; Kavehvash, Z ; Shabany, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
This article focuses on analyzing the aliasing artifact in millimeter-wave imaging systems, with a special focus on multistatic arrays. The current framework to analyze the behavior of multistatic structures is based on the effective aperture concept. Based on this framework, an equivalent monostatic array, approximating the position of each transmitter-receiver pair by its midpoint, is used to quantify the response and efficiency of the system. Although this framework helps to simplify the study of the complex characteristics of multistatic arrays, it suffers from vital deficiencies. Especially, it fails to describe the aliasing artifacts, seen in the image of some sparse multistatic...
A Novel Model for Three-Dimensional Imaging Using Interferometric ISAR in Curved Target Flight Paths
, Ph.D. Dissertation Sharif University of Technology ; Bastani, Mohammad Hasan (Supervisor)
Abstract
A Synthetic Aperture Radar (SAR) is a system which collects the received signal from a ground target area along linear motion of a flying vehicle carrying it, in order to provide a very high resolution 2D image of it. In Inverse SAR (ISAR), the radar is fixed on the ground and the data collection is performed along the linear motion of the aerial target. Using a second receiver antenna close to the main transceiver antenna of ISAR, it is possible to make a three-dimensional (3D) image of the target, or equivalently find the 3D coordinates of the target scattering points. Such system is called bistatic, monopulse or interferometric ISAR (InISAR). In the conventional model of ISAR, the flying...
Target detection by passive coherent FM based bistatic radar
, Article 2008 International Conference on Radar, Radar 2008, Adelaide, SA, 2 September 2008 through 5 September 2008 ; October , 2008 , Pages 412-415 ; 9781424423224 (ISBN) ; Nayebi, M. M ; Norouzi, Y ; CEA Technologies Pty Ltd; Cranfield University; Diversified Technologies, Inc; Information, Telecommunications and Electronic Engineering (ITEE); Board of Engineers Australia ; Sharif University of Technology
2008
Abstract
Bistatic passive radars have many advantages over the monostatic ones because they are undetectable and silent. In passive coherent location, the original source of energy is derived from a waveform of opportunity in the environment and the re-radiated energy from the target is processed to decide about the existence of the target. More over bistatic radars receive forward scatters from target in place of the backscatters in monostatics systems. As a result of the larger forward scattered RCS, the stealth targets can be detected easier. Passive radar does not need any frequency allocation so are very attractive for surveillance. Multipath effects and direct path interference are two problems...