- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 16th International Symposium on Wireless Communication Systems (ISWCS) - Oulu, Finland (2019.8.27-2019.8.30)] 2019 16th International Symposium on Wireless Communication Systems (ISWCS) - A Differential Reflection-Type Phase Shifter Based on CPW Coupled-Line Coupler in 45nm CMOS SOI
摘要： This paper presents a mm-wave fully differential coplanar waveguide (CPW) vertically-coupled lines coupler and a reflection type phase shifter (RTPS) based on the proposed coupler. The use of grounded strip line structure for vertical coupling in CPW based coupler provides not only the improved coupling properties than the edge coupling but also provides the opportunity of using surrounding area efficiently to reduce area. The proposed coupler and phase shifter are designed and fabricated in 45nm CMOS SOI technology. Measured insertion loss of the coupler is ~ 6 dB from 18 to 43 GHz. A digitally controlled parallel LC load is used for controlling the phase of the phase shifter. Measured phase tuning range is 115 degrees, with insertion loss variation of 4.5 to 9 dB, for a frequency range of 39 GHz to 45 GHz. Total drawn area of the phase shifter is 0.214 mm2. The area of the proposed RTPS is smaller than the recently published state-of-the-art structures.
关键词： 5G,mmWave,Phased Array,Hybrid Coupler,Phase shifter,CMOS SOI
更新于2025-09-11 14:15:04
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Signal-to-Noise Ratio of True-Time Delay Beamformers Based on Microwave Photonic Links Using an Incoherent Broadband Optical Source
摘要： The signal-to-noise ratio (SNR) of true-time delay beamformers based on microwave photonic links using an incoherent broadband optical source (IBOS) is investigated. A comprehensive theory considering the bias angle of the Mach-Zehnder modulator employed in the microwave photonic link is presented to analyze the SNR. When the RF signal at the fundamental frequency is fed by the beamformer, the SNR is a function of the bias angle, the frequency of the applied RF signal, the modulation index, the system dispersion and the shape of the IBOS. We ?nd that by biasing the MZM near the minimum transmission point, the SNR at the fundamental frequency is maximized. On the other hand, by exactly biasing the MZM at the minimum transmission point, the RF signal at the double frequency can be fed by the beamformer with maximum power. The maximum SNR at the double frequency is a function of the frequency of the applied RF signal, the system dispersion and the shape of the IBOS while its dependence on the modulation index is eliminated. In both cases, the relationship between the SNR and the frequency of the RF signal, the system dispersion and the shape of the IBOS is also investigated. An experiment is carried out to verify the theoretical analysis, and the experiment results agree well with the calculation.
关键词： modulation,dispersion,true-time delay,incoherent broadband optical source,signal-to-noise ratio,Microwave photonics,phased array antennas
更新于2025-09-11 14:15:04
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Research on a Novel Kind of Dual Polarized Stacked Printed Antenna
摘要： This paper presents a dual polarized antenna with high isolation for a wide-angle scanning phased array radar. For the proposed antenna, the electronic and magnetic resources are realized through a printed monopole antenna and a slot ring antenna, respectively. A metal reflector ground was introduced to achieve the unidirectional pattern, and the ratio of front to back of the pattern was improved. The printed monopole and slot ring antenna are fed by the coaxial and electromagnetic couplings, respectively. The radiation fields emitted by the electronic current resource and magnetic current resource are approximately orthogonal to each other among large space ranges. The measured port isolation of the designed antenna is above 20 dB, and the wide beam performance can be observed. The feasibility of the proposed antenna scheme is verified.
关键词： dual polarized antenna,high isolation,printed monopole antenna,phased array radar,slot ring antenna,wide-angle scanning
更新于2025-09-11 14:15:04
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[IEEE 2018 Second International Conference on Inventive Communication and Computational Technologies (ICICCT) - Coimbatore (2018.4.20-2018.4.21)] 2018 Second International Conference on Inventive Communication and Computational Technologies (ICICCT) - Beamforming Using Phased Coprime MIMO Radar
摘要： This paper proposes a new method of beamforming for colocated MIMO radar with the coprime arrays. The proposed method splits the transmitting array into multiple overlapped subarrays and then transmits a coherent signal through each subarray, to achieve a maximum power in the desired direction. However, the signals from distinct subarrays are independent to preserve the diversity bene?t of the MIMO radar. Thus, the proposed method exploits the advantages of both phased array and MIMO radars as well as the coprime arrays. Simulation results are presented to signify the beampattern and the signal to interference plus noise ratio performance of the proposed method and to compare with the earlier methods such as phased array radar, MIMO radar and the coprime MIMO radar.
关键词： Phased array radar,MVDR,MIMO radar,Coprime array
更新于2025-09-10 09:29:36
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PLANAR PHASED ARRAY CALIBRATION BASED ON NEAR-FIELD MEASUREMENT SYSTEM
摘要： Matrix method for phased array calibration is an excitation reconstruction method by solving the linear equations based on the linear relationship between the measured near-field data and element excitations. In this paper, we propose a modified matrix method, in which the phased array model is simplified, to measure the element excitations of planar phased array. Our method reduces measurement time greatly at the cost of introducing some calibration errors. The introduced calibration errors can be minimized with the array excitation strategy proposed in this paper. Experimental results validate the effectiveness of our methods in calibrating planar phased arrays.
关键词： excitation reconstruction,near-field measurement,phased array calibration,matrix method
更新于2025-09-10 09:29:36
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[IEEE 2018 10th International Conference on Communication Software and Networks (ICCSN) - Chengdu (2018.7.6-2018.7.9)] 2018 10th International Conference on Communication Software and Networks (ICCSN) - An Amplitude-phase Measurement Method of Phased Array Antenna Based on Self-Calibration RF Channel
摘要： Caused by the amplitude-phase error of phased array antenna, the pattern performance unable to meet the optimum design results. Thus, the phase and amplitude of phased array antenna should be measured and calibrated. An measurement method of phased array antenna based on self-calibration RF channel is presented in this paper. First of all, the initial amplitude-phase is measured by self-calibration RF channel. Secondly, the modified value related to self-calibration RF channel is achieved by use of Mid-field receiving power calculation method. Finally, the actual amplitude and phase weighting factor of phased array antenna is obtained, based on calibration of the initial amplitude-phase with the modified value. The comparison of planar near-field measured results show that the proposed method is feasible and efficient.
关键词： amplitude-phase measurement method,self-calibration,phased array antenna
更新于2025-09-10 09:29:36
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[IEEE 2018 15th European Radar Conference (EuRAD) - Madrid, Spain (2018.9.26-2018.9.28)] 2018 15th European Radar Conference (EuRAD) - Initial Design of Phase-Frequency Scanned Array Using CRLH Leaky-Wave Antennas
摘要： Initial design of phase-frequency scanned array using composite right/left-handed (CRLH) waveguide leaky-wave antennas (LWAs) is studied in this paper. The array consists of 32 frequency scanning CRLH LWAs that are fed by a phased feed system. Two-dimensional (2D) beam steering capability is achieved in the plane normal to the array aperture and verified by the full-wave simulations. This array is capable of scanning to 61° from backward to forward directions in the frequency-scan plane and 17° in the phase-scan plane. The beamwidth is approximately 2° with ?20 dB sidelobe level (SLL) in the frequency-scan plane and 2.5° with maximum ?10 dB SLL in the phase-scan plane. Compared with traditional 2D scanning array, the feed system of this phase-frequency scanned array can be simplified significantly.
关键词： phase-frequency scanned array,leaky-wave antenna (LWA),two-dimensional (2D) beam steering,composite right/left-handed (CRLH),phased array
更新于2025-09-09 09:28:46
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[IEEE 2018 IEEE International Conference on Computational Electromagnetics (ICCEM) - Chengdu, China (2018.3.26-2018.3.28)] 2018 IEEE International Conference on Computational Electromagnetics (ICCEM) - Design of Wideband and Wide-Angle Scanning Phased Array Based on Wideband EBG Structure
摘要： A linear dipole array based on wideband electromagnetic bandgap (EBG) is designed in this paper. The linear array is organized along the H plane and the simulated results of an infinite array show that it features a bandwidth of 24.1% (from 5.1 to 6.5GHz) while scanning to 70° in the H plane with VSWR<2.5. Then, a 1×20 finite linear dipole array based on the above element configuration is designed. The array has the ability to scan up to 75° with a gain reduction less than 3 dB at 5GHz, and scan up to 80° with a gain reduction less than 3 dB at 5.7GHz, and scan up to 88° with a gain reduction about 4 dB at 6.1GHz.
关键词： wide-angle scanning,phased array,wideband,electromagnetic bandgap
更新于2025-09-09 09:28:46
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The Polarimetric L-Band Imaging Synthetic Aperture Radar (PLIS): Description, Calibration, and Cross-Validation
摘要： The polarimetric L-band imaging synthetic aperture radar (PLIS) is a high spatial resolution (better than 6 m) airborne synthetic aperture radar system that has been dedicated to scientific research into civilian applications since 2010. The weight of PLIS is ～38 kg, allowing it to be installed aboard small low-cost aircraft, with two antennas used to measure the full backscatter matrix for a swath between 15° and 50° on each side of the flight direction. Calibration based on a total of 96 calibration points and a homogeneous forest during the two recent soil moisture active passive experiments (SMAPEx-4 and 5) showed an overall radiometric accuracy of 0.58 dB (root-mean-square error) over trihedral passive radar calibrators. Independent evaluation based on polarimetric active radar calibrators showed an amplitude imbalance of 0.17 dB with a standard deviation of 0.15 dB and a phase imbalance of 3.87° with a standard deviation of 2.86°. Two calibrated phased-array L-Band synthetic aperture radar-2 (PALSAR-2) images with different observation modes (ScanSAR and Stripmap) were compared with the calibrated PLIS images. The agreement between PALSAR-2 Stripmap and PLIS had a root mean square difference of 1.27 dB and a correlation coefficient of 0.87. Further comparisons over different landcover types confirmed that homogeneous forest and grassland areas constitute optimal targets for cross-validation and/or calibration.
关键词： Calibration and validation,phased-array L-Band synthetic aperture radar-2 (PALSAR-2),cross-calibration,synthetic aperture radar (SAR),polarimetric L-band imaging SAR (PLIS)
更新于2025-09-09 09:28:46
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[IEEE ICASSP 2018 - 2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) - Calgary, AB (2018.4.15-2018.4.20)] 2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) - Real-Time Total Focusing Method for Ultrasonic Imaging of Multilayered Object
摘要： In imaging of multilayered object, total focusing method (TFM) combined with ray-tracing appeals to numerous researchers because of its superior image quality. But lots of iterative computation to calculate the incident points greatly increases its processing time. Based on line scan-conversion algorithm and Snell’s principle, this paper proposes an efficient method to calculate the incident point. By dividing the image area into multiple regions, the time-consuming iterative calculation of point of incidence (POI) is eliminated. After introducing this method into TFM, the time complexity of Region-Division (RD) TFM is reduced by one order of magnitude. The simulation experiments validate that the imaging speed of RD-TFM is improved dozens of times compared to traditional TFM with ray-tracing. Besides, RD-TFM applies to multilayered objects with both planar and non-planar interface.
关键词： Ultrasonic phased array,Multi-layered object,Full matrix capture,Total focusing method
更新于2025-09-09 09:28:46