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oe1(光电查) - 科学论文

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出版时间
  • 2018
研究主题
  • Schottky diodes
  • frequency multipliers
  • submillimeter-wave technology
  • terahertz technology.
  • Submillimeter-wave sources
应用领域
  • Optoelectronic Information Science and Engineering
机构单位
  • California Institute of Technology
201 条数据
?? 中文（中国） ▾

  • [IEEE 2018 IEEE 5G World Forum (5GWF) - Silicon Valley, CA, USA (2018.7.9-2018.7.11)] 2018 IEEE 5G World Forum (5GWF) - EIRP, TRP, Partial TRP and Radiated Immunity For 5G millimeter Wave Device Compliance

    摘要： 5G millimeter wave devices and low frequency devices have different FCC compliance requirements. The 5G millimeter wave devices must meet new parameters such as sum of equivalent isotropic power (EIRP) and total radiated power (TRP). Massive MIMO devices must be evaluated differently as compared to conventional MIMO devices. The network telecommunications equipment EMC standard, GR1089 sets test levels for radiated immunity testing at millimeter wave frequencies. This document discusses 5G device test draft test methods and testability challenges for meeting FCC compliance and new radiated immunity requirements

    关键词： Radiated Immunity,massive MIMO,TRP,millimeter Wave,OTA,Sum of EIRP,5G,Partial TRP

    更新于2025-09-23 15:21:01

  • [IEEE 2018 IEEE 5G World Forum (5GWF) - Silicon Valley, CA, USA (2018.7.9-2018.7.11)] 2018 IEEE 5G World Forum (5GWF) - Long distance and high bandwidth wireless link tests for a 39 GHz to 28 GHz 5G low-cost repeater

    摘要： This paper presents a low-cost millimeter-wave repeater for range extension in a 5G fixed wireless access system. It simply converts the wireless fronthaul signals in the 39 GHz band to the wireless access signals in the 28 GHz band without any base-band signal processing. Initial outdoor over-the-air tests with a simplified setup proved that a sufficient linearity can easily be achieved even over long fronthaul link length. Moreover, high bandwidth measurements with multi-carrier 5GTF pre-5G test signals demonstrated excellent EVM values with high signal-to-noise ratios enabling the required high data rates.

    关键词： fixed wireless access,5G communication systems,linearity,millimeter-wave

    更新于2025-09-23 15:21:01

  • [IEEE 2018 IEEE MTT-S International Microwave Workshop Series on 5G Hardware and System Technologies (IMWS-5G) - Dublin (2018.8.30-2018.8.31)] 2018 IEEE MTT-S International Microwave Workshop Series on 5G Hardware and System Technologies (IMWS-5G) - On the Impact of Spillover Losses in 28 GHz Rotman Lens Arrays for 5G Applications

    摘要： This work demonstrates the sensitivity of lens antenna arrays operating at millimeter-wave (mmWave) frequencies. Considering a Rotman lens array in receive mode, our investigation focuses on its most imperative defect: aberration of electromagnetic (EM) energy. Aberration leads to spillover of electric fields to neighboring ports, reducing the lens’ ability to focus the EM energy to a desired port. With full EM simulations, we design a 28 GHz, 13 beam and 13 array port Rotman lens array to characterize its performance with the aforementioned impairment. Our findings show that the impact of aberration is more pronounced when the beam angles are close to the array end-fire. More critically, the corresponding impact of aberration on the desired signal and interference powers is also investigated for an uplink multiuser cellular system operating at 28 GHz. The presented results can be used as a reference to re-calibrate our expectations for Rotman lens arrays at mmWave frequencies.

    关键词： Rotman lens,5G,spillover losses,millimeter-wave,aberration

    更新于2025-09-23 15:21:01

  • P-OMP-IR ALGORITHM FOR HYBRID PRECODING IN MILLIMETER WAVE MIMO SYSTEMS

    摘要： This paper presents a P-OMP-IR algorithm for the hybrid precoding problem in millimeter wave (mm-Wave) multiple-input multiple-output (MIMO) systems. In the proposed approach, the digital precoding matrix is updated via the orthogonal matching pursuit (OMP) method, and the analog precoding matrix is re?ned column by column using the dominant singular value and corresponding singular vectors of a residual matrix successively. During the re?ning phase of the analog precoding matrix, an extended power method is designed to calculate the dominant singular value and the corresponding left and right singular vectors, which is able to reduce the computational complexity signi?cantly. Simulation results show that the proposed algorithm can not only reduce the residual of the hybrid precoder e?ectively, but also improve the spectral e?ciency consistently.

    关键词： millimeter wave,MIMO systems,orthogonal matching pursuit,P-OMP-IR algorithm,spectral efficiency,hybrid precoding

    更新于2025-09-23 15:21:01

  • Hybrid Precoding for Wideband Millimeter-Wave Systems with Finite Resolution Phase Shifters

    摘要： In this paper, we study the hybrid analog-digital precoding for OFDM based-wideband millimeter wave (mmwave) communication systems. Since the analog precoding matrix is performed in the time domain and used for the entire bandwidth while the digital precoding matrices are performed on a per-subcarrier basis, the resulting wideband hybrid precoding problem becomes very complicated. Moreover, in practice phase shifter (PS) usually has only finite resolution, which brings more difficulties. To solve the resulting difficult problem, we propose an efficient algorithm by leveraging the penalty decomposition method. Simulation results are finally provided to confirm the effectiveness and superiority of the proposed algorithm and show the performance improvement than the existing algorithm.

    关键词： finite resolution phase shifter,wideband hybrid precoding,decomposition method,Wideband millimeter wave communication

    更新于2025-09-23 15:21:01

  • [IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Synchrotron and optical probing of hybrid organic-inorganic perovskite halides for photovoltaics

    摘要： Supporting high data rate wireless connectivity among wearable devices in a dense indoor environment is challenging. This is primarily due to bandwidth scarcity when many users operate multiple devices simultaneously. The millimeter-wave (mmWave) band has the potential to address this bottleneck, thanks to more spectrum and less interference because of signal blockage at these frequencies. In this paper, we explain the potential and challenges associated with using mmWave for wearable networks. To provide a means for concrete analysis, we present a system model that admits easy analysis of dense, indoor mmWave wearable networks. We evaluate the performance of the system while considering the unique propagation features at mmWave frequencies, such as human body blockages and re?ections from walls. One conclusion is that the non-isotropy of the surroundings relative to a reference user causes variations in system performance depending on the user location, body orientation, and density of the network. The impact of using antenna arrays is quanti?ed through analytic closed-form expressions that incorporate antenna gain and directivity. It is shown that using directional antennas, positioning the transceiver devices appropriately, and orienting the human user body in certain directions depending on the user location result in gigabits-per-second achievable ergodic rates for mmWave wearable networks.

    关键词： personal communication networks,wearable computers,signal to noise ratio,Millimeter wave communication,performance analysis,analytic models,indoor communication,internet of things,virtual reality

    更新于2025-09-23 15:19:57

  • Sampled-Data Adaptive ESO Based Composite Control for Nano-Positioning Systems

    摘要： In this paper, we demonstrate ultra-fast millimeter wave beam steering with settling times below 50 ps. A phased array antenna with two elements is employed to realize beam steering. The phased array feeder is implemented with a recently introduced time delay line that provides, at the same time, an ultra-fast tunability, broadband operation, and continuous tuning. Our implementation is used to perform symbol-by-symbol steering. In our demonstration, the beam direction is switched between two sequentially transmitted symbols toward two receivers placed 30° apart. We show the successful symbol-by-symbol steering for data streams as fast as 10 GBd. The suggested scheme shows that the ultra-fast beam steering is becoming practical and might ultimately enable novel high bit-rate multiple access schemes.

    关键词： microwave photonics,millimeter wave communication,Ultra-fast beam steering,radio access network

    更新于2025-09-23 15:19:57

  • Detecting Laser-Volatilized Salts with a Miniature 100-GHz Spectrometer

    摘要： Rotational transitions are unique identi?ers of molecular species, including isotopologues. This article describes the rotational detections of two laser-volatilized salts, NaCl and KCl, made with a miniature Fourier transform millimeter-wave (FTmmW) cavity spectrometer that could one day be used to measure solid composition in the ?eld or in space. The two salts are relevant targets for icy moons in the outer solar system, and in principle, other molecular solids could be analyzed with the FTmmW instrument. By coupling the spectrometer to a collisionally cooling laser ablation source, (a) we demonstrate that the FTmmW instrument is sensitive enough to detect ablation products, and (b) we use the small size of the FTmmW cavity to measure ablation product signal along the carrier gas beam. We ?nd that for 532 nm nanosecond pulses, ablated molecules are widely dispersed in the carrier-gas jet. In addition to the miniature spectrometer results, we present several complementary measurements intended to characterize the laser ablation process. For pulse energies between 10 and 30 mJ, the ablation product yield increases linearly, reaching approximately 1012 salt molecules per 30 mJ pulse. Using mass spectrometry, we observe Li+, Na+, and K+ in the plumes of ablated NaCl, KCl, and LiCl, which implies dissociation of the volatilized material. We do not observe salt ions (e.g., NaCl+). However, with 800 nm femtosecond laser pulses, the triatomic ion clusters Li2Cl+, Na2Cl+, and K2Cl+ are produced. Finally, we observe incomplete volatilization with the nanosecond pulses: some of the ejecta are liquid droplets. The insights about ablation plume physics gleaned from these experiments should guide future implementations of the laser-volatilization technique.

    关键词： KCl,Fourier transform millimeter-wave,FTmmW,rotational transitions,NaCl,mass spectrometry,outer solar system,icy moons,laser-volatilized salts,laser ablation

    更新于2025-09-23 15:19:57

  • A fully electronically tunable millimeter wave lab-in-waveguide nano-fluidic sensor

    摘要： In this paper, we report an ultra-sensitive millimeter wave (mm-wave) reflection liquid sensor, which is electronically tunable, non-invasive, and label-free. The reflection liquid sensor is based on the impedance match technique. It is implemented in a rectangular waveguide structure, which makes the interaction between mm-wave and liquid under test (LUT) in a closed environment, forms a nano-fluidic lab-in-waveguide liquid sensor, and isolates the interference of surroundings. The reflection liquid sensor shows high sensitivity to permittivity change of the LUTs. Taking the ethanol-distilled water as benchmark, a more than 62 dB ethanol-distilled water contrast is experimentally achieved. The detection limit is 0.05% ethanol in volumetric concentration with a 4 dB signal difference, which is the best performance of the microwave and mm-wave liquid sensors publicly reported until now. The ultra-sensitive reflection sensor can be used for bio-chemical sensing. The lab-in-waveguide biosensor is also compatible with microfluidics.

    关键词： impedance match,electronically tunable,liquid sensor,label-free,millimeter wave,non-invasive

    更新于2025-09-23 15:19:57

  • [IEEE 2019 IEEE BiCMOS and Compound semiconductor Integrated Circuits and Technology Symposium (BCICTS) - Nashville, TN, USA (2019.11.3-2019.11.6)] 2019 IEEE BiCMOS and Compound semiconductor Integrated Circuits and Technology Symposium (BCICTS) - A Compact Ka-Band Transformer-Coupled Power Amplifier for 5G in 0.15um GaAs

    摘要： In this paper we present the design of a compact and broadband transformer-coupled power ampli?er in a 0.15μm GaAs technology. The power ampli?er achieves an output power of 26.5dBm and 31% power added ef?ciency, 12.6dB of small signal gain with a fractional bandwidth of 40%. The ampli?er enables up to 21.6dBm, 19.9dBm of average output power while amplifying a 6Gb/s, 9Gb/s 64-QAM signal respectively at 28GHz with an EVM<-25dB without any digital pre-distortion. To the author’s knowledge, this is the ?rst time transformer-coupled matching networks are used in a GaAs power ampli?er leading to very compact matching structures compared to bulky transmission line.

    关键词： 5G,Power Ampli?er,Millimeter wave integrated circuits,Transformer-Coupled,Ka-band

    更新于2025-09-23 15:19:57