ACES Publication Search
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| Title: | ACES Journal January 2023 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 1969 KB |
| Title: | ACES Journal January 2023 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 186 KB |
| Title: | ACES Journal January 2023 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 10121 KB |
| Title: | Research on OTA Testing Optimization of 5G IoT Devices |
| Abstract: | Over-the-air (OTA) testing for wireless devices is crucial to guarantee actual network performance. Current OTA testing requires respectively 266 and 62 grid points for Total Radiated Power (TRP) and Total Isotropic Sensitivity (TIS) measurement. For 5G Internet of Things (IoT) devices, especially for low transmit dutycycle devices, this number of grid points could lead to an unacceptably large amount of test time. Therefore, test time reduction is significant. The objective of this paper is to determine a suitable measurement grid for OTA testing of 5G IoT devices which balances measurement grid uncertainty/errors with test time. Two reference patterns representing a reasonable worst-case scenario of IoT devices are proposed for measurement uncertainty (MU) analysis of different grid configurations. The effects of different grid configurations on OTA testing accuracy are evaluated. The determination of associated MU term is proposed and determined based on statistical analysis. Finally, the reduction of grid points from currently required 62 (30/30 in theta/phi) to 32 (45/36) could save roughly 50% test time while requiring an uncertainty increase of less than 0.2 dB, which is acceptable for OTA testing of 5G IoT devices. |
| Author(s): | X. Chen, X. Liu, S. Sun |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 723 KB |
| Title: | Experimental Investigation of Decoupling Effect on the Nonlinearity of Power Amplifiers in Transmitter Array |
| Abstract: | In a practical compact massive multiple-input multiple-output (MIMO) transmitter array, each antenna or subarray is connected to an independent power amplifier (PA) with a modest power capacity in order to avoid the challenging demand of high-power capacity of a single PA for the whole array and to facilitate the power dissipation of the transmitter array. In this case, there is simply not enough space for an isolator between the antenna and the PA. As a result, the array mutual coupling changes the load impedances of the PAs and thus further increases the MIMO transmitter’s nonlinearity. In this work, the decoupling effect on the transmitter array’s linearity is investigated experimentally by using an array prototype with PAs. The mutual coupling of the array can be effectively suppressed using a hybrid decoupling structure. Two continuous-wave (CW) signals at different frequencies are injected into the PAs, and the output signal of each PA is measured via a coupler. The measured results show that with effective mutual coupling reduction, the PA interference is greatly suppressed by up to 16 db and the amplitude of the desired signal is enhanced by up to 10 db. |
| Author(s): | F. Peng, F. Yang, B. Liu, X. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 2445 KB |
| Title: | A Hybrid EMC Testing Facility: Combining Transmission Line and Reverberation Chamber Measurement System |
| Abstract: | By combining a transmission line system (TLS) and a reverberation chamber (RC), a hybrid electromagnetic compatibility (EMC) testing facility is designed and constructed. Generally, the lowest usable frequency (LUF) of an RC is limited by its dimension, which limits the application of RCs for EMC testing at low frequencies. Therefore, to improve the field uniformity (FU) of an RC at frequencies lower than the LUF, a TLS is integrated into the RC. After optimizing the load resistance, length, and width of the TLS, the resonant frequency and electric field spikes of the hybrid system are eliminated. The FU of the E-field in the system is greatly improved in the frequency range of 0-30 MHz. Moreover, using an oscillating wall stirrer in the RC, the FU satisfies the standard (IEC 61000-4-21) above 80 MHz. Results show that combining the TLS and the RC testing system could be widely used for EMC testing in the frequency range of 0-30 MHz and 80 MHz-6 GHz. |
| Author(s): | K. Chen, W. Qi, P. Peng, H. Wang, X. Shen, Y. Zhao, Q. Xu |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 3448 KB |
| Title: | Reducing the Measurement Time in a Reverberation Chamber to Less than 1 Second |
| Abstract: | To increase the speed of the measurement, a time-efficient multi-probe system in a reverberation chamber (RC) is validated. The system consists of 4 printed circuit board (PCB) switches integrating with 128 probe antennas. By using solid-state switches, all antennas can be switched over in sequence in less than 1 second. Typical characteristics of the RC and the total radiated power (TRP) of the device under test (DUT) are performed to verify the validity of this configuration. Compared with the RC using mechanical stirrers, this system shows its superiority in terms of testing efficiency. |
| Author(s): | W. Xia, W. Qi, F. Fang, C. Li, L. Xing, Q. Xu |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 6060 KB |
| Title: | Uncertainty Quantification Method of Crosstalk Involving Braided-Shielded Cable |
| Abstract: | In this paper, in view of the uncertainty of geometric parameters of braided-shielded cable and structural parameters of the shield in practical problems, polynomial chaos expansions (PCE) is used to explore the uncertainty quantification of a crosstalk calculation model of braided-shielded cable. First, the model based on multi-conductor transmission line theory is expanded by PCE. Second, the truncation degrees of polynomials and sample size of PCE are determined by the leave-one- out method, and the statistical characteristic parameters of crosstalk are obtained by combining coefficients of polynomials. Compared with the calculation results of the Monte Carlo method, the mean value, standard deviation and probability density function obtained by the two methods are basically consistent, but the PCE method has obvious advantages in calculation efficiency. Finally, the influence of input variable parameters in the crosstalk calculation model of braided-shielded cable are calculated by combining the PCE and the Sobol’s global sensitivity analysis method, which provides theoretical guidance for the electromagnetic compatibility design of electrical and electronic equipment using braided-shielded cable. |
| Author(s): | T. Tan, T. Jiang, H. Jiang, T. Wang, M. Ca |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 901 KB |
| Title: | Recent Developments of Shielding Effectiveness for Electronics and Information Devices |
| Abstract: | With the increase wireless communications, many wireless devices and equipment have been invented for special applications, resulting in mutual interference that might destroy the systems or distort signal in-transmission. One of the effective methods to reduce or eliminate interference is to devise a shielding to block the unwanted interference in between the approaching systems, circuits, devices, etc. Thus, shielding and estimation of its effectiveness are very important in order to protect the information devices from potential interference and to improve the performance of information equipment. In this survey, we present the recent developments of the shielding and shielding effectiveness techniques and methods, and give a design for an electromagnetic shielding structure. |
| Author(s): | P. Xu, T. Jiang, M. Wang, Y. Li, Z. Huang |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 5976 KB |
| Title: | Combined Application of Partition Clustering Classification and Gerchberg-Papoulis Optimization Algorithm for Spherical Near Field Antenna Measurements |
| Abstract: | An adaptive sampling and optimized extrapolation scheme for spherical near-field antenna testing is proposed. The method relies on the partition clustering classification algorithm and Voronoi classification to divide a small amount of initial data into subclasses and cells. The sampling density and rates of variation between adjacent sampling points are used as an overall metric function to evaluate the sampling dynamics at each location. Appropriate interpolation is performed in the highly dynamic region to increase the effective data in the near-field samples. The Gerchberg- Papoulis algorithm extrapolates the unnecessary interpolation region to improve the near-field sampling accuracy. This method uses a small amount of initial nearfield sampled data for near-far field conversion to achieve the same precision as uniform oversampling. The feasibility and stability of the algorithm are proved from the actual measurement results. |
| Author(s): | F. Peng, Y. Ma, Y. Ren, B. Liu, X. Liu, Z. Wang, L. Zhao, X. Chen, Z. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 3319 KB |
| Title: | A Compact Four-way Quadrature Power Splitter for 5G Low-band Applications |
| Abstract: | This article introduces an ultra-compact fourway quadrature power splitter (4W-QPS) based on a novel transmission-line compression technique called double-path zigzag microstrip line (DP-ZML). Detailed design techniques with modular approach are disclosed for the state-of-the-art 5G low-band applications. The theoretical predictions are verified with experimental results through a fabricated prototype that operates from 696.55 to 876.03 MHz with >15 dB return-losses and isolations, and 90°±4° quadrature phase between adjacent outputs. The compact size of this 4W-QPS is achieved at 0.21λg×0.21λg at a center frequency of 786 MHz. |
| Author(s): | S. Gao, H. Wang, K. L. Chung, Y. Li, K. Zheng, L. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 1945 KB |
| Title: | Removing the Froissart Doublets in a Rational Interpolation Based on Loewner Matrix |
| Abstract: | In order to implement wide band frequency sweeping, the S-parameters can be fitted with an adaptive rational interpolation based on Loewner matrix. However, the errors in the sampling data may lead to Froissart doublets, which look like spikes in the curve. In this paper, a novel technique is proposed to remove these doublets. At first, the rational expression is converted into the sum of partial fractions by solving two generalized eigenvalue problems. After that, the partial fraction term with the smallest imaginary part of the pole and relatively large absolute value is considered to generate the doublets. Removing this term results in a smooth rational polynomial, which is validated by the example of a passive circuit simulated by finite element method (FEM). |
| Author(s): | H. Yuan, J. Ren, Y. Li, X. Huang |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 2992 KB |
| Title: | Super-Broadband Rectifier with Wide-band Resistance Compression Network and Harmonic Cycling for RF-Harvesting |
| Abstract: | In this paper, a super-broadband (SBB) rectifier using a wideband resistance compression network (WRCN) and harmonic cycling is proposed, simulated, fabricated, measured and analyzed in detail for the harvesting of ambient radio frequency (RF) energy. Meanwhile, impedance compression and matching are achieved to implement the SBB using WRCN and impedance operation networks. Additionally, harmonic cycling structure and bending technology are employed to improve the power conversion efficiency (PCE) and reduce the size, respectively. For demonstration, a prototype of the proposed rectifier is fabricated and measured. The measured results are in good accordance with the simulated ones, indicating that the rectifier can provide high efficiency and ultra-broadband rectification characteristics. A PCE over 50% is realized at 3.5 GHz with an input power range of 6–24 dBm, and a PCE of 75% is obtained at an input power of 18 dBm. The PCE is greater than 50% at 17 dBm with an input frequency of 2.7-4.6 GHz. This work can find significant applications in the development of RF-harvesting. |
| Author(s): | X. Liu, D. Zhang, Y. Li, Z. Huang |
| File Type: | Journal Paper |
| Issue: | Volume: 38 Number: 1 Year: 2023 |
| Download Link: | Click here to download PDF File Size: 543 KB |