List of Articles تزویج متقابل

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  1 - Robust DOA Estimation in the Presence of Mutual Coupling effect with Application in Auxiliary Vehicle Positioning
  Zahra Dehghani Naser Parhizgar Hamid Azad
  As an important branch of the Internet of Vehicles (IoV), vehicle positioning has drawn extensive attention. Traditional positioning systems based on a global positioning system incur long delays, and may fail due to obstructions. In this article, we propose an auxiliar More

  As an important branch of the Internet of Vehicles (IoV), vehicle positioning has drawn extensive attention. Traditional positioning systems based on a global positioning system incur long delays, and may fail due to obstructions. In this article, we propose an auxiliary positioning architecture, whose core is to estimate the direction of arrival (DOA) of signals from landmarks, such as wireless access points, utilizing a sensor array in the vehicle. Due to space limitations, the array may be placed in an arbitrary geometry and may suffer from mutual coupling effects, and it is possible that the effect of mutual coupling between the array elements greatly reduces the independence of the elements of the array, and this effect involves the interaction of each element with its nearby objects. Mutual coupling in antenna arrays can critically degrade the performance of signal processing algorithms. In this paper, a new and accurate form of mutual impedance matrix (MIM) is used to compensate for the effect of mutual coupling in uniform linear arrays (ULA) by a new method based on solving the boundary value problem for all array elements. By using the MIM in the DOA estimation algorithms, these algorithms will be robust to the mutual coupling effect. The simulation results confirm the performance improvement of the proposed DOA estimation algorithm. The proposed architecture can obtain robust self-localization with existing vehicular ad hoc networks, and it can collaborate with other positioning systems to provide a safe driving environment. Manuscript profile
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  2 - Design and Fabrication of Novel Single- and Dual-band Bandpass Filters with Modern Zero-Degree Feed Structure for Wireless Communications
  Mohammad Reza Zobeyri Ahmadreza Eskandari
  In this paper, there are three novel bandpass filters (BPFs), consist of single- and dual-band, presented in a same size, which all the filters, have been designed, optimized and finally fabricated and measured, based on a primary structure and using planar microstrip t More

  In this paper, there are three novel bandpass filters (BPFs), consist of single- and dual-band, presented in a same size, which all the filters, have been designed, optimized and finally fabricated and measured, based on a primary structure and using planar microstrip technology. Each of the generated passbands, is resonated by the use of one of the two existing types of resonator structures. The larger resonators, as main-structures of the filter with a stepped-impedance features, by appling 0°-feed structure and electrical coupling in-between, create the first passband at 0.9 GHz. The smaller resonators as sub-structures, with dual-spiral topology, are in the same size and uniform-impedance, and with symmetrical feeding and internal coupling, are embedded in the main-structures to generate and control the higher passband at 1.8GHz. The existence of a cross-coupling between the sub-structures, suppresses any harmonics in the stop-band and generates additional transmission zeros on both sides of the upper passband. Overal dimensions of the innovative filters with a miniaturizing approach, are reduced from 0.163λg*0.09λg to 0.092λg*0.08λg in terms of the guided wavelength, which is the most compacted structure compared with other filters. According to 0.7 dB and 0.5 dB, the obtained insertion losses of the first and second passbands of the dual-band BPF respectively, the lowest losses have been achieved, compared with other examined dual-band BPFs. Finally three prototypes for global systems for mobile communication, were fabricated and measured. A good agreement between the measured and simulated results indicates realizing the goals and ingenious methods of this design. Manuscript profile
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  3 - Design and Simulation of a Compact UWB MIMO Antenna with Mutual Coupling Reduction
  Narges Malekpour Mohammad Amin Honarvar Abdolmehdi Dadgarpour
  In this paper, A compact multiple-input-multiple-output (MIMO) antenna with a small size of 26×31mm2 is proposed for portable ultrawideband (UWB) applications. The antenna consists of two square-monopole antenna with microstrip-fed by a 50- Ω printed on one side o More

  In this paper, A compact multiple-input-multiple-output (MIMO) antenna with a small size of 26×31mm2 is proposed for portable ultrawideband (UWB) applications. The antenna consists of two square-monopole antenna with microstrip-fed by a 50- Ω printed on one side of the substrate. To enhance isolation and increase impedance bandwidth, two long ground stubs are added to the ground plane on the other side. Simulation is used to study the antenna performance in terms of reflection coefficients at the two input ports, coupling between the two input ports, radiation pattern, realized peak gain, efficiency and envelope correlation coefficient. Results show that the MIMO antenna has an impedance bandwidth ( for S22< -10 dB) of larger than 3.1–10.6 GHz, low mutual coupling ( for S21< 3 dB) of less than -16 dB, and a low envelope correlation coefficient of less than 0.003 across the frequency band, making it a good candidate for portable UWB applications. Manuscript profile