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    Systems and Methods for Selecting Reconfigurable Antennas in MIMO Systems
    31.
    发明申请
    Systems and Methods for Selecting Reconfigurable Antennas in MIMO Systems 有权
    在MIMO系统中选择可重构天线的系统和方法

    公开(公告)号：US20150341103A1

    公开(公告)日：2015-11-26

    申请号：US14522910

    申请日：2014-10-24

    Applicant: Drexel University ,  Politecnico di Milano

    Inventor： Daniele Piazza ,  John Kountouriotis ,  Michele D'Amico ,  Kapil R. Dandekar

    IPC: H04B7/06 ,  H04B7/04 ,  H01Q9/04

    CPC classification number: H01Q1/1257 ,  H01Q3/24 ,  H01Q9/0407 ,  H01Q13/10 ,  H04B7/0434 ,  H04B7/0689

    Abstract: A method allows reconfigurable multi-element antennas to select the antenna configuration in MIMO, SIMO and MISO communication system. This selection scheme uses spatial correlation, channel reciprocal condition number, delay spread and average Signal to Noise Ratio (SNR) information to select the antenna radiation pattern at the receiver. Using this approach, it is possible to achieve capacity gains in a multi-element reconfigurable antenna system without modifying the data frame of a conventional wireless communication system. The capacity gain achievable with this configuration selection approach is calculated through numerical simulations using reconfigurable circular patch antennas at the receiver of a MIMO system that employs minimum mean square error receivers for channel estimation. Channel capacity and Bit Error Rate (BER) results show the improvement offered relative to a conventional antenna selection technique for reconfigurable MIMO systems.

    Abstract translation: 一种方法允许可重配置的多元天线在MIMO，SIMO和MISO通信系统中选择天线配置。 该选择方案使用空间相关性，信道倒数条件数，延迟扩展和平均信噪比（SNR）信息来选择接收机处的天线辐射图。 使用这种方法，可以在不修改常规无线通信系统的数据帧的情况下实现多元可重构天线系统中的容量增益。 使用该配置选择方法可实现的容量增益通过使用在使用最小均方误差接收器进行信道估计的MIMO系统的接收机处的可重构圆形贴片天线的数值模拟来计算。 信道容量和误码率（BER）结果显示出相对于可重配置MIMO系统的常规天线选择技术的改进。

    JOINT PAPR REDUCTION AND RATE ADAPTIVE ULTRASONIC OFDM PHYSICAL LAYER FOR HIGH DATA RATE THROUGH-METAL COMMUNICATIONS
    32.
    发明申请
    JOINT PAPR REDUCTION AND RATE ADAPTIVE ULTRASONIC OFDM PHYSICAL LAYER FOR HIGH DATA RATE THROUGH-METAL COMMUNICATIONS 审中-公开
    用于通过金属通信的高数据速率的联合PAPR减少和速率自适应超声OFDM物理层

    公开(公告)号：US20140161169A1

    公开(公告)日：2014-06-12

    申请号：US14119338

    申请日：2012-05-25

    Applicant: DREXEL UNIVERSITY

    Inventor： Richard Primerano ,  Kevin Wanuga ,  Magdalena Bielinski ,  Kapil R. Dandekar ,  Moshe Kam ,  Guillermo A. Sosa

    IPC: H04L27/26 ,  H04L27/01

    CPC classification number: H04L27/262 ,  H04B11/00 ,  H04L1/0005 ,  H04L5/0007 ,  H04L5/0046 ,  H04L27/01 ,  H04L27/2614 ,  H04L27/362 ,  Y02D70/144 ,  Y02D70/48

    Abstract: A link adaptive orthogonal frequency-division multiplexed (OFDM) ultrasonic physical layer is provided that is capable of high data rate communication through metallic structures. The use of an adaptive OFDM subcarrier-based modulation technique mitigates the effects of severe frequency selective fading of the through-metal communication link and improves spectral efficiency by exploiting the slow-varying nature of the channel. To address the potential ill effects of peak-to-average power ratio (PAPR) and to make more efficient use of the power amplifiers in the system, the invention modifies and implements a symbol rotation and inversion-based PAPR reduction algorithm in the adaptive OFDM framework. This joint adaptive physical layer is capable of increasing data rates by roughly 220% in comparison to conventional narrowband techniques at average transmit powers of roughly 7 mW while constrained to a desired BER.

    Abstract translation: 提供了能够通过金属结构进行高数据速率通信的链路自适应正交频分复用（OFDM）超声波物理层。 使用基于OFDM子载波的自适应调制技术减轻了通过金属通信链路的严重频率选择性衰落的影响，并通过利用信道的慢变性质来提高频谱效率。 为了解决峰均功率比（PAPR）的潜在不良影响，并且为了更有效地利用系统中的功率放大器，本发明在自适应OFDM中修改并实现了基于符号旋转和反演的PAPR降低算法 框架。 与传统的窄带技术相比，这种联合自适应物理层能够将数据速率提高大约220％，平均发射功率大约为7mW，同时被限制到期望的BER。

    MOISTURE SENSING USING RADIO FREQUENCY IDENTIFICATION (RFID)
    34.
    发明申请
    MOISTURE SENSING USING RADIO FREQUENCY IDENTIFICATION (RFID) 有权

    公开(公告)号：US20230003669A1

    公开(公告)日：2023-01-05

    申请号：US17929059

    申请日：2022-09-01

    Applicant: Drexel University

    Inventor： Md Abu Saleh Tajin ,  Kapil R. Dandekar

    IPC: G01N22/04 ,  H01Q9/26 ,  H01Q1/27 ,  H01Q1/22

    Abstract: A passive UHF (Ultra High Frequency, 902-928 MHz) RFID-based fabric (such as a diaper) moisture sensor is low-cost, user-friendly, reusable, washable, environment-friendly and comes with an extended on-body read range of 3.6 meters with baby diapers and 4.4 meters with adult diapers. The external reader unit is connected to the internet or a local network, and may automatically notify the parents or caregivers as soon as the presence of moisture is detected.

    Symmetric Encryption Key Generation Using Wireless Physical Layer Information Without Sharing Any Information Pertinent To The Key
    35.
    发明申请
    Symmetric Encryption Key Generation Using Wireless Physical Layer Information Without Sharing Any Information Pertinent To The Key 有权

    公开(公告)号：US20220345306A1

    公开(公告)日：2022-10-27

    申请号：US17720610

    申请日：2022-04-14

    Applicant: Drexel University

    Inventor： Cem Sahin ,  Kapil R. Dandekar

    IPC: H04L9/08 ,  H04L9/14

    Abstract: Symmetric keys are generated by an algorithm that uses the randomness from the wireless PHY layer to extract the keys. When used with reconfigurable antennas, the algorithm yields longer keys. By using the randomness from the wireless PHY layer, the algorithm solves the issue of secure information leakage to the wireless channel during key establishment phase. The algorithm also omits transmitting anything secure during this phase and prevents any intruder from obtaining information related to the key. This approach can automatically secure the communications over open wireless networks (those without authentication or encryption) or closed wireless networks using other methods of authentication.

    Adaptive Pursuit Learning Method To Mitigate Small-Cell Interference Through Directionality
    40.
    发明申请
    Adaptive Pursuit Learning Method To Mitigate Small-Cell Interference Through Directionality 审中-公开

    公开(公告)号：US20180098330A1

    公开(公告)日：2018-04-05

    申请号：US15720951

    申请日：2017-09-29

    Applicant: Drexel University

    Inventor： Danh H. Nguyen ,  Anton Paatelma ,  Harri Saarnisaari ,  Nagarajan Kandasamy ,  Kapil R. Dandekar

    IPC: H04W72/08 ,  H04W74/04 ,  H04W72/04 ,  H04W16/06 ,  G06N99/00

    Abstract: A learning protocol for distributed antenna state selection in directional cognitive small-cell networks is described. Antenna state selection is formulated as a nonstationary multi-armed bandit problem and an effective solution is provided based on the adaptive pursuit method from reinforcement learning. A cognitive small cell testbed, called WARP-TDMAC, provides a useful software-defined radio package to explore the usefulness of compact, electronically reconfigurable antennas in dense small-cell configurations. A practical implementation of the adaptive pursuit method provides a robust distributed antenna state selection protocol for cognitive small-cell networks. Test results confirm that directionality provides significant advantages over omnidirectional transmission which suffers high throughput reduction and complete link outages at above-average jamming or cross-link interference power.

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