- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Beam Training and Allocation for Multiuser Millimeter Wave Massive MIMO Systems
摘要： We investigate beam training and allocation for multiuser millimeter wave massive MIMO systems. An orthogonal pilot based beam training scheme is first developed to reduce the number of training times, where all users can simultaneously perform the beam training with the base station (BS). As the number of users increases, the same beam from the BS may point to different users, leading to beam conflict and multiuser interference. Therefore, a quality-of-service (QoS) constrained (QC) beam allocation scheme is proposed to maximize the equivalent channel gain of the QoS-satisfied users, under the premise that the number of the QoS-satisfied users without beam conflict is maximized. To reduce the overhead of beam training, two partial beam training schemes, an interlaced scanning (IS) and a selection probability (SP) based schemes, are proposed. The overhead of beam training for the IS-based scheme can be reduced by nearly half while the overhead for the SP-based scheme is flexible. Simulation results show that the QC-based beam allocation scheme can effectively mitigate the interference caused by the beam conflict and significantly improve the spectral efficiency while the IS-based and SP-based schemes significantly reduce the overhead of beam training at the cost of sacrificing spectral efficiency a little.
关键词： beam allocation,massive MIMO,Millimeter wave (mmWave) communications,beam training
更新于2025-09-23 15:23:52
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Spatial-Based Chipless RFID System
摘要： Conventional techniques in chipless RFID systems are incapable of fully overcoming the key challenges of modern identification applications, including high data capacity, low tag cost and reliable operation. The idea of electromagnetic (EM) imaging in chipless RFID systems is a promising technique that shows many advantages over other conventional approaches. This paper reviews conventional chipless RFID technology and provides a comprehensive analysis of advanced millimeter wave spatial-based (also known as image-based) chipless RFID systems with an optimized MIMO-SAR technique for high-resolution image acquisition and a quick reading process.
关键词： Multiple-input multiple-output (MIMO),Millimeter wave (mmwave),Chipless radio frequency identification (RFID),EM imaging,Virtual antenna array,Synthetic aperture radar (SAR)
更新于2025-09-23 15:22:29
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77-GHz mmWave antenna array on liquid crystal polymer for automotive radar and RF front-end module
摘要： This paper introduces a low‐cost, high‐performance mmWave antenna array module at 77 GHz. Conventional waveguide transitions have been replaced by 3D CPW‐microstrip transitions which are much simpler to realize. They are compatible with low‐cost substrate fabrication processes, allowing easy integration of ICs in 3D multi‐chip modules. An antenna array is designed and implemented using multilayer coupled‐fed patch antenna technology. The proposed 16 × 16 array antenna has a fractional bandwidth of 8.4% (6.5 GHz) and a 23.6‐dBi realized gain at 77 GHz.
关键词： broadband transition,3D transition,mmWave antenna array,automotive radar module,proximity-coupled patch antenna
更新于2025-09-23 15:22:29
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Hybrid Beamforming for Millimeter Wave Systems Using the MMSE Criterion
摘要： Hybrid analog and digital beamforming (HBF) has recently emerged as an attractive technique for millimeter-wave (mmWave) communication systems. It well balances the demand for sufficient beamforming gains to overcome the propagation loss and the desire to reduce the hardware cost and power consumption. In this paper, the mean square error (MSE) is chosen as the performance metric to characterize the transmission reliability. Using the minimum sum-MSE criterion, we investigate the HBF design for broadband mmWave transmissions. To overcome the difficulty of solving the multi-variable design problem, the alternating minimization method is adopted to optimize the hybrid transmit and receive beamformers alternatively. Specifically, a manifold optimization based HBF algorithm is firstly proposed, which directly handles the constant modulus constraint of the analog component. Its convergence is then proved. To reduce the computational complexity, we then propose a low-complexity general eigenvalue decomposition based HBF algorithm in the narrowband scenario and three algorithms via the eigenvalue decomposition and orthogonal matching pursuit methods in the broadband scenario. A particular innovation in our proposed alternating minimization algorithms is a carefully designed initialization method, which leads to faster convergence. Furthermore, we extend the sum-MSE based design to that with weighted sum-MSE, which is then connected to the spectral efficiency based design. Simulation results show that the proposed HBF algorithms achieve significant performance improvement over existing ones, and perform close to full-digital beamforming.
关键词： Minimum mean square error (MMSE),Alternating optimization,Manifold optimization (MO),Hybrid analog and digital beamforming (HBF),Millimeter-wave (mmWave) communications
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE 5G World Forum (5GWF) - Silicon Valley, CA, USA (2018.7.9-2018.7.11)] 2018 IEEE 5G World Forum (5GWF) - A 5G Radio-Light SDN Architecture for Wireless and Mobile Network Access in Buildings
摘要： The Internet of Radio-Light architecture provides both direct WLAN type access to the Internet using 5G RAN as well as access to the Internet via Mobile Networks using a 5G mmWave and VLC Radio Access Network (RAN) within buildings. A SDN is used to manage the various different packet flows between the RAN, the Internet Interface and the Mobile Network User and Control plane interfaces for SmartPhone, Tablet PCs, HDTVs and Virtual Reality headsets within buildings.
关键词： SDN,NFV,mmWave,5G,VLC
更新于2025-09-23 15:21:21
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Adaptive AoA and Polarization Estimation for Receiving Polarized mmWave Signals
摘要： This paper proposes a novel hybrid dual-polarized antenna array which exploits two orthogonally-collocated dipoles to capture the full power of a polarized millimeter wave signal. To maximize the received signal-to-noise ratio (SNR), we study the adaptive angle-of-arrival and polarization state estimation, and develop a differential beam tracking algorithm and a cross-correlation-to-power ratio polarization tracking algorithm for interleaved hybrid dual-polarized arrays. Simulation results verify the superior performance of the proposed algorithms, and confirm the significant improvement of SNR obtained by using the proposed array and algorithms.
关键词： angle-of-arrival estimation,Hybrid dual-polarized antenna array,polarization state estimation,mmWave
更新于2025-09-23 15:21:21
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Cluster-based Resource Allocation and User Association in mmWave Femtocell Networks
摘要： In millimeter wave(mmW) dense femto-networks, major challenges are overcoming the performance loss imposed by channel and managing the co-channel interference. The former is due to mmW susceptibility to pathloss and shadowing and the latter is due to density of the network. We cope with both challenges by a clustering method designed for mmW environment. In our approach, the femto access points (FAP) and femto users (FU) are clustered based on having the most line of sight connectivity. We modify this binary optimization problem into a continuous problem using deductive penalty functions and solve it by difference of two convex functions (D.C.) programming. Our clustering algorithm achieves higher data rate compared to the foremost clustering method. We also propose a technique to assign FUs to FAPs in each cluster which has near-optimal performance and polynomial time complexity. We solve mixed integer nonlinear programming of power and sub-channel allocation by D.C. programming. Instead of using the deductive penalty terms in D.C. programming, we penalize the objective function in a multiplicative manner. Thus, the penalty term depends on both constraint violation and objective function. Our scheme achieves around 10% higher data rate compared to the method using deductive penalty terms.
关键词： D.C. programming,Resource allocation,Multiplicative penalty function,User association,Clustering,mmWave,Femto cell
更新于2025-09-23 15:21:21
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[IEEE 2018 IEEE 5G World Forum (5GWF) - Silicon Valley, CA, USA (2018.7.9-2018.7.11)] 2018 IEEE 5G World Forum (5GWF) - Interference Mitigation via Beam Range Biasing for 5G mmWave Coexistence with Incumbents
摘要： In this paper, we propose two interference mitigation techniques to enable the coexistence of ?fth-generation new radio (5G-NR) with existing incumbent systems at millimeter frequencies. In particular, we propose to assign offsets, or bias values, to the base station beams such that users are discouraged to associate to the beams that are aligned with the incumbent receiver. We present a case study to evaluate the 5G uplink interference experienced at an existing incumbent in a dense urban city. Our results show that beam biasing provides better balance in 5G coverage and interference protection when compared to spatial exclusion zones.
关键词： mmWave,coexistence,5G,spectrum sharing,interference mitigation
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE International Electron Devices Meeting (IEDM) - San Francisco, CA, USA (2019.12.7-2019.12.11)] 2019 IEEE International Electron Devices Meeting (IEDM) - Integrated DFB Laser Diode and High-efficiency Mach-Zehnder Modulator using Membrane III-V Semiconductors on Si Photonics Platform
摘要： This paper presents a 3-D statistical channel impulse response (IR) model for urban line of sight (LOS) and non-LOS channels developed from 28- and 73-GHz ultrawide-band propagation measurements in New York City, useful in the design of 5G wireless systems that will operate in both the ultra-high frequency/microwave and millimeter-wave (mmWave) spectrum to increase channel capacities. A 3GPP-like stochastic IR channel model is developed from measured power delay profiles, angle of departure, and angle of arrival power spectra. The extracted statistics are used to implement a channel model and simulator capable of generating 3-D mmWave temporal and spatial channel parameters for arbitrary mmWave carrier frequency, signal bandwidth, and antenna beamwidth. The model presented here faithfully reproduces realistic IRs of measured urban channels, supporting air interface design of mmWave transceivers, filters, and multi-element antenna arrays.
关键词： 28 GHz,multipath,time cluster spatial lobe (TCSL),spatial lobe (SL),statistical simulator,5G,spatial channel model (SCM),73 GHz,Channel model,millimeter-wave (mmWave) propagation,3-D ray-tracing,time cluster (TC),impulse response (IR)
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE Photonics Society Summer Topical Meeting Series (SUM) - Ft. Lauderdale, FL, USA (2019.7.8-2019.7.10)] 2019 IEEE Photonics Society Summer Topical Meeting Series (SUM) - Ultra-high Capacity Wireless Communication Enabled by Photonic Technologies
摘要： This letter presents a probabilistic omnidirectional millimeter-wave path loss model based on real-world 28 GHz and 73 GHz measurements collected in New York City. The probabilistic path loss approach uses a free space line-of-sight propagation model, and for non-line-of-sight conditions uses either a close-in free space reference distance path loss model or a floating-intercept path loss model. The probabilistic model employs a weighting function that specifies the line-of-sight probability for a given transmitter-receiver separation distance. Results show that the probabilistic path loss model offers virtually identical results whether one uses a non-line-of-sight close-in free space reference distance path loss model, with a reference distance of 1 meter, or a floating-intercept path loss model. This letter also shows that site-specific environmental information may be used to yield the probabilistic weighting function for choosing between line-of-sight and non-line-of-sight conditions.
关键词： mmWave,ray-tracing,probabilistic path loss,floating-intercept,close-in free space reference distance,site-specific
更新于2025-09-23 15:19:57