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2021-01-01

Call-for-Papers for PIER Special Issues

Being an open access on-line journal, PIER gives great prominence to special issues that draw together significant and emerging works to promote key advances on specific topics. The special issues are devoted to timely, relevant, and cutting-edge research and aim to provide a unique platform for researchers interested in selected topics.We are now calling for papers for the following PIER Spe

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The 43rd PIERS in Hangzhou, CHINA
21 - 25, November 2021
(from Sunday to Thursday)

--- Where microwave and lightwave communities meet

Hybrid PIERS: Onsite + Web Access

Important Dates:

  • 20 June, 2021 --- Abstract Submission Deadline
  • 20 August, 2021 --- Pre-registration Deadline
  • 25 August, 2021 --- Full-length Paper Submission Deadline
  • 20 September, 2021 --- Preliminary Program
  • 5 October, 2021 --- Advance Program
  • 20 October, 2021 --- Final Program

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Join Us in this Harvest Season - Onsite + Web Access

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PIERS 2021, Hangzhou, CHINA

Late autumn - PIERS 2021 Hangzhou, CHINA

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About PIER

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Progress In Electromagnetics Research

PIER Journals are a family of journals supported by the PhotonIcs and Electromagnetics Research Symposium (PIERS), which has become a major symposium in the area related to photonics and electromagnetics. The scope includes all aspects of electromagnetic theory plus its wide-ranging applications. Hence, it includes topics motivated by mathematics, sciences as well as topics inspired by advanced technologies. The spectrum ranges from very low frequencies to ultra-violet frequencies. The length scale spans from nanometer length scale to kilometer length scale. The physics covers the classical regime as well as the quantum regime.

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PIER

ISSN: 1070-4698
2021-04-03

L-Band Radar Scattering and Soil Moisture Retrieval of Wheat, Canola and Pasture Fields for Smap Active Algorithms

Huanting Huang, Tien-Hao Liao, Seung Bum Kim, Xiaolan Xu, Leung Tsang, Thomas J. Jackson, and Simon Yueh

Wheat, canola, and pasture are three of the major vegetation types studied during the Soil Moisture Active Passive Validation Experiment 2012 (SMAPVEX12) conducted to support NASA's Soil Moisture Active Passive (SMAP) mission. The utilized model structure is integrated in the SMAP baseline active retrieval algorithm. Forward lookup tables (data-cubes) for VV and HH backscatters at L-band are developed for wheat and canola fields. The data-cubes have three axes: vegetation water content (VWC), root mean square (RMS) height of rough soil surface and soil permittivity. The volume scattering and doublebounce scattering of the fields are calculated using the distorted Born approximation and the coherent reflectivity in the double-bounce scattering. The surface scattering is determined by the numerical solutions of Maxwell equations (NMM3D). The results of the data-cubes are validated with airborne radar measurements collected during SMAPVEX12 for ten wheat fields, five canola fields, and three pasture fields. The results show good agreement between the data-cube simulation and the airborne data. The root mean squared errors (RMSE) were 0.82 dB, 0.78 dB, and 1.62 dB for HH, and 0.97 dB, 1.30 dB, and 1.82 dB for VV of wheat, canola, and pasture fields, respectively. The data-cubes are next used to perform the time-series retrieval of the soil moisture. The RMSEs of the soil moisture retrieval are 0.043 cm3/cm3, 0.082 cm3/cm3, and 0.082 cm3/cm3 for wheat, canola, and pasture fields, respectively. The results of this paper expand the scope of the SMAP baseline radar algorithm for wheat, canola, and pastures formed and provide a quantitative validation of its performance. It will also have applications for the upcoming NISAR (NASA-ISRO SAR Mission).....

  • In this research project, the hardware implementation of a Field-Programmable Gate Array (FPGA) based Fast Fourier Transform (FFT) will be carried out by using Verilog Hardware Description Language (HDL). Since FFT serves as the core for the Range Doppler Algorithm (RDA) in Synthetic Aperture Radar (SAR) processing, it is of paramount importance to evaluate the algorithm and its computational complexity for the design of an efficient FFT hardware architecture. The design process and Verilog hardware description language which is used to describe and model a digital FPGA-based SAR processor will be introduced. Detailed explanation of the hardware implementation for FFT and Inverse Fast Fourier Transform (IFFT) in SAR processing are thus presented. The performance evaluations of the proposed processors including the comparison of the proposed processor with MATLAB-based processor, timing considerations of the processor, and lastly the hardware resources usage considerations are delivered at the end of this paper.....
  • 2021-04-16

    A New Reflectionless Filter Composed of Discharging Circuit

    Aixia Yuan, Shao-Jun Fang, Ying Wang, Yu Lin Feng, and Tielin Zhang
    A new reflectionless filter with discharging circuit is presented. Under the premise of keeping the original filter unchanged, a discharging circuit is added. The relationship between the passband and stopband of the discharging circuit and the original filter is similar to the duality of the circuit. Without affecting the performance of the original filter, the reflected energy of the original filter is discharged to the ground through discharging circuit, so as to achieve no reflection of the filter, avoiding the interference to the input. Analytical design equations are provided so that the reflectionless filter can be designed. According to this design method, the reflectionless dual-band bandpass filter is designed and fabricated. Simulation and measurement results are in agreement. It has good reflectionless performance. The feasibility of the design method is verified.....
  • In this article, a hybrid inversion algorithm based on an innovative stochastic algorithm, namely, the bat algorithm (BA) is proposed. Electromagnetic inverse scattering problems are ill-posed and are often transformed into optimization problems by defining a suitable cost function. As typical methods to solve optimization problems, stochastic optimization algorithms are more flexible and have better global searching ability than deterministic algorithms. However, they share a common disadvantage: heavy computing load. This directly restricts the application of the algorithms in high-dimensional problems and real-time imaging environments. To solve this issue, diffraction tomography (DT) is introduced to provide a reference for the initialization of the BA. Furthermore, the hybrid method makes full use of the complementary advantages of linear reconstruction algorithms and stochastic optimization algorithms to improve accuracy and efficiency at the same time. Moreover, in order to avoid the algorithm falling into local extrema, a linear attenuation strategy of the pulse emission rate is proposed to enable more bats to perform global search in the early stage of the algorithm. In the numerical experiments for different types of dielectric objects, the reconstruction results of this hybrid BA-based algorithm are compared with those of the DT and the particle swarm optimization (PSO).....
  • 2021-04-17

    Frequency Reconfigurable Antenna with Dual-Band and Dual-Mode Operation

    Ting-Yan Liu, Jun-Yan Chen, and Jeen-Sheen Row
    A frequency reconfigurable antenna with dual-band operation is presented. The antenna has a circular radiating patch loaded with an annular slot, and the slotted patch is shorted to the ground plane with four conducting posts. The antenna has three feed ports. Two of the ports are used to excite the slot mode resonant at a lower frequency, and broadside radiation with dual orthogonal linear polarizations can be obtained. The other port is used to excite the monopolar-patch mode resonant at a higher frequency, and conical radiation with vertical polarization can be yielded. To reconfigure the operation frequencies, four varactors are symmetrically placed across the annular slot. The simulated results indicate that the resonant frequency of the slot mode can be tuned from 1.62 to 1.17 GHz when the capacitance of the varactors is varied from 0.6 to 1.8 pF; besides, for each capacitance value, the impedance bandwidth of the antenna operating in the monopolar-patch mode can cover the frequencies from 2.4 to 2.5 GHz. Experiments are also carried out to validate the simulated data.....