2020/3

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Recent Submissions

Now showing 1 - 5 of 20
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    A Planar Dual-Band UHF RFID Tag for Metallic Items
    (Společnost pro radioelektronické inženýrství, 2020-09) Bouazza, Hajar; Lazaro, Antonio; Bouya, Mohsine; Hadjoudja, Abdelkader
    In this paper, a comparison of three tags based on modified patches for UHF RFID in term of size and read range performance is proposed. The antenna structure consists of a patch with an open stub and meander line for feed. The tags are dedicated to being mounted on metallic items and to operate on dual-band frequencies (European and American UHF RFID frequency bands). Moreover, the structure of the antennas is planar without any via holes or multilayers for a low cost and easy fabrication. Good agreement between simulation and experimental results has been obtained at 866 MHz and 915 MHz.
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    A Compact Circular Loop Inspired Frequency and Bandwidth Reconfigurable Antenna for 4G, 5G, and X- Band Applications
    (Společnost pro radioelektronické inženýrství, 2020-09) Rasool, Maryam; Khan, Aabia; Bhatti, Farooq; Ijaz, Bilal; Iftikhar, Adnan
    This paper presents a printed patch antenna design to achieve frequency and bandwidth reconfigurability. Two RF PIN diodes are simultaneously operated to achieve the multi-reconfigurability operation. The patch is inspired from a circular loop design. The basic structure of loop is altered, and PIN diodes are integrated into the patch. The antenna operates in dual band configuration at 3.42 and 8.02 GHz in the diodes ‘OFF’ state, whereas the antenna switches to triple band operation at 2.21, 4.85, and 10.19 GHz in the diodes ‘ON’ state. Moreover, the antenna also exhibits an increased bandwidth from 7.54 to 12 GHz in the diodes ‘ON’ state, as compared to a narrow bandwidth from 7.71 to 8.48 GHz in the diodes ‘OFF’ state. The proposed antenna structure is implemented and fabricated using FR4 epoxy substrate of relative permittivity 4.4, and thickness 1.6 mm. Implemented design exhibits measured gains of 3.06 dBi, 2.81 dBi, and 2.92 dBi at 2.21, 4.85, and 10.19 GHz in the PIN diodes ‘ON’ state, respectively, while in the PIN diodes ‘OFF’ state, at 3.42 GHz the gain is 3.03 dBi and at 8.02 GHz the gain is 3.37 dBi. Overall, simulation results agree well with the measured results.
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    Robust Student’s T Distribution Based PHD/CPHD Filter for Multiple Targets Tracking Using Variational Bayesian Approach
    (Společnost pro radioelektronické inženýrství, 2020-09) Li, Peng; Xu, Chen; Wang, Wenhui; Su, Shuzhi
    Measurement-outliers caused by non-linear observation model or random disturbance will lead to the accuracy decline of a target tracking filter. This paper proposes a robust probability hypothesis density (PHD) filter to handle the measurement-outlier problem based on Student’s T Kalman (TK) filtering technique and Variational Bayesian (VB) method. First, the non-standard measurement noise is considered to follow the Student’s T distribution. Second, the TK filtering technique is employed to update the target states. Third, the posterior likelihood is updated by the VB approach. Simulation results show that the proposed method can reduce the optimal subpattern assignment (OSPA) error in the non-standard observation scenarios with measurement-outliers, compared with other typical multiple target tracking filters.
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    A Broadband High Gain Circularly Polarized Antenna System for Cognitive Radio
    (Společnost pro radioelektronické inženýrství, 2020-09) Parida, Rajeev Kumar; Swain, Rajanikanta; Panda, Dhruba Charan; Mishra, Rabindra Kishore
    This paper proposes a broadband high gain LHCP (left hand circular polarized) antenna system using a microstrip line fed slot antenna, reflecting surfaces, and linear polarization (LP) to circular polarization (CP) transformer screen. Gain enhancement principle adopts Fabry-Perot (FP) method using phase compensation in partially reflecting surface (PRS) for increasing bandwidth from 720 MHz to 1.14 GHz. For linear polarization, the system gain is 20.1 dBi at 13.8 GHz with a bandwidth of 1.01 GHz. Using a polarization transformer screen for circular polarization, marginally decreases the gain to 18.8 dBi pulling down the frequency to 13.75 GHz with 3 dB axial ratio. Simulated results agree well with measured results from a fabricated prototype.
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    A Novel User and Antenna Selection Techniques in Massive MIMO 5G Wireless Communication System
    (Společnost pro radioelektronické inženýrství, 2020-09) Sheikh, Tasher Ali; Bora, Joyatri; Hussain, Md Anwar
    In this paper, we have proposed a new paradigm for user scheduling in large-scale multiple-input multiple-output (MIMO) time division duplexing (TDD) system. In this paper, we have selected the users from different groups with semi-orthogonal (SO) and random criterion. We separate the users in different groups with the K-means clustering algorithm which assigns the users into different groups. After user groups are so determined, we use two new user selection paradigms where users are selected in two methods- firstly we select the users in intra-group those are SO with each other along with it also SO with other groups’ users. Secondly, users are selected from inter-group those are SO with each other also SO with other group users. In both the selection schemes antennas are scheduled based on the maximum gain of the channel. In the results, it is noticed that in intra-group with semi-orthogonal user selection (SUS) and antenna selection (AS) using the zero-forcing (ZF) precoding shown the highest systems rate. We also evaluated the computation cost of our modified proposed algorithm which is exposed in table-1. We explored the efficiency of the proposed schemes through MATLAB simulations.