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Theodore S. Rappaport

Bio: Theodore S. Rappaport is an academic researcher from New York University. The author has contributed to research in topics: Path loss & Multipath propagation. The author has an hindex of 112, co-authored 490 publications receiving 68853 citations. Previous affiliations of Theodore S. Rappaport include University of Waterloo & University of Texas at Austin.


Papers
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Patent
04 Nov 2002
TL;DR: In this paper, a system and method for measuring and monitoring wireless network performance in campus and indoor environments provides for embedding measured network and signal properties at one or more locations within a facility into a site specific computer model which represents the facility.
Abstract: A system and method for measuring and monitoring wireless network performance in campus and indoor environments provides for embedding measured network and signal properties at one or more locations within a facility into a site specific computer model which represents the facility. The computer representation is preferably three dimensional. The system and method allows for automatic, periodic, or location specific taking of measurements, and automatic or periodic embedding of measured data. The system and method allows real time or non-real time measurement and storing of performance data, and the invention is useful for test, measurement, verification, and in-situ or remote monitoring for on-going validation and maintenance of wireless networks.

31 citations

Proceedings ArticleDOI
24 Sep 2000
TL;DR: In this paper, power delay profiles (PDPs) and power angle profiles (PAPs) were measured in various indoor and short-range outdoor environments and compared with site-specific environments.
Abstract: This paper presents measurement results and models for 60 GHz channels. Multipath components were resolved in time by using a sliding correlator with 10 ns resolution, and in space by sweeping a directional antenna with 70 half power azimuthal beamwidth around the azimuth. Power delay profiles (PDPs) and power angle profiles (PAPs) were measured in various indoor and short-range outdoor environments. Detailed multipath structure was retrieved from PDPs and PAPs, and compared with site-specific environments. Results show an excellent correlation between the propagation environments and the multipath channel structures. The measurement results confirm that the majority of the multipath components can be determined from image based ray tracing techniques for LOS applications. For NLOS propagation through walls, the metallic structure of composite walls must be considered for propagation predictions. From the recorded PDPs and PAPs, received signal power and statistical parameters of angle-of-arrival (AOA) and time-of-arrival (TOA) were also calculated.

30 citations

Patent
24 Mar 2004
TL;DR: In this article, a building database manipulator is used to build databases for a variety of physical environments including definitions of buildings, terrain and other site parameters, by scanning in or rapidly editing data.
Abstract: A Building Database Manipulator to build databases for a variety of physical environments including definitions of buildings, terrain and other site parameters, by scanning in or rapidly editing data. Raster scans may be entered or object files in various formats may be used as input. Detailed information is stored in the drawing database about the object's location, radio frequency attenuation, color, and other physical information such as electrical characteristics and intersections of the object with the ground, floors, ceilings, and other objects when objects are formatted in a drawing. The formatting process is strictly two-dimensional in nature, but the resulting drawing is a true three-dimensional environment. The user sees the three-dimensional building structure by altering the views. The resulting database may be used in a variety of modeling applications, but is especially useful for engineering, planning and management tools for in-building or microcell wireless systems. Grouping objects in layers allows for simultaneous conversion of all objects in one layer to have certain predetermined attributes (e.g., converting objects to be made from glass versus cement; converting objects within a layer to have a uniform, smaller or larger, height or width dimension).

29 citations

Posted Content
TL;DR: NYUSIM 2.0 is presented, an improved channel simulator which can simulate spatially consistent channel realizations based on the existing drop-based channel simulator NYUSIM 1.6.1, making it a valuable measurement- based channel simulator for fifth-generation and beyond mmWave communication system design and evaluation.
Abstract: Accurate channel modeling and simulation are indispensable for millimeter-wave wideband communication systems that employ electrically-steerable and narrow beam antenna arrays. Three important channel modeling components, spatial consistency, human blockage, and outdoor-to-indoor penetration loss, were proposed in the 3rd Generation Partnership Project Release 14 for mmWave communication system design. This paper presents NYUSIM 2.0, an improved channel simulator which can simulate spatially consistent channel realizations based on the existing drop-based channel simulator NYUSIM 1.6.1. A geometry-based approach using multiple reflection surfaces is proposed to generate spatially correlated and time-variant channel coefficients. Using results from 73 GHz pedestrian measurements for human blockage, a four-state Markov model has been implemented in NYUSIM to simulate dynamic human blockage shadowing loss. To model the excess path loss due to penetration into buildings, a parabolic model for outdoor-to-indoor penetration loss has been adopted from the 5G Channel Modeling special interest group and implemented in NYUSIM 2.0. This paper demonstrates how these new modeling capabilities reproduce realistic data when implemented in Monte Carlo fashion using NYUSIM 2.0, making it a valuable measurement-based channel simulator for fifth-generation and beyond mmWave communication system design and evaluation.

29 citations

Patent
18 Apr 2006
TL;DR: In this article, a system and method for creating a site specific representation of an environment is described, which consists of sending an RF signal and receiving a reflected RF signal, and based upon determining characteristics of the reflected RF signals, characteristics of an obstruction in the environment are computed.
Abstract: A system and method for creating a site specific representation of an environment are disclosed. The system and method comprise sending an RF signal and receiving a reflected RF signal. Based upon determining characteristics of the reflected RF signal, characteristics of an obstruction in the environment are computed. Finally, a site specific representation of the environment based upon the computed characteristics is created.

29 citations


Cited by
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Journal ArticleDOI

[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
TL;DR: The concept of sensor networks which has been made viable by the convergence of micro-electro-mechanical systems technology, wireless communications and digital electronics is described.

17,936 citations

Journal ArticleDOI
TL;DR: Using distributed antennas, this work develops and analyzes low-complexity cooperative diversity protocols that combat fading induced by multipath propagation in wireless networks and develops performance characterizations in terms of outage events and associated outage probabilities, which measure robustness of the transmissions to fading.
Abstract: We develop and analyze low-complexity cooperative diversity protocols that combat fading induced by multipath propagation in wireless networks. The underlying techniques exploit space diversity available through cooperating terminals' relaying signals for one another. We outline several strategies employed by the cooperating radios, including fixed relaying schemes such as amplify-and-forward and decode-and-forward, selection relaying schemes that adapt based upon channel measurements between the cooperating terminals, and incremental relaying schemes that adapt based upon limited feedback from the destination terminal. We develop performance characterizations in terms of outage events and associated outage probabilities, which measure robustness of the transmissions to fading, focusing on the high signal-to-noise ratio (SNR) regime. Except for fixed decode-and-forward, all of our cooperative diversity protocols are efficient in the sense that they achieve full diversity (i.e., second-order diversity in the case of two terminals), and, moreover, are close to optimum (within 1.5 dB) in certain regimes. Thus, using distributed antennas, we can provide the powerful benefits of space diversity without need for physical arrays, though at a loss of spectral efficiency due to half-duplex operation and possibly at the cost of additional receive hardware. Applicable to any wireless setting, including cellular or ad hoc networks-wherever space constraints preclude the use of physical arrays-the performance characterizations reveal that large power or energy savings result from the use of these protocols.

12,761 citations

Journal ArticleDOI
Simon Haykin1
TL;DR: Following the discussion of interference temperature as a new metric for the quantification and management of interference, the paper addresses three fundamental cognitive tasks: radio-scene analysis, channel-state estimation and predictive modeling, and the emergent behavior of cognitive radio.
Abstract: Cognitive radio is viewed as a novel approach for improving the utilization of a precious natural resource: the radio electromagnetic spectrum. The cognitive radio, built on a software-defined radio, is defined as an intelligent wireless communication system that is aware of its environment and uses the methodology of understanding-by-building to learn from the environment and adapt to statistical variations in the input stimuli, with two primary objectives in mind: /spl middot/ highly reliable communication whenever and wherever needed; /spl middot/ efficient utilization of the radio spectrum. Following the discussion of interference temperature as a new metric for the quantification and management of interference, the paper addresses three fundamental cognitive tasks. 1) Radio-scene analysis. 2) Channel-state estimation and predictive modeling. 3) Transmit-power control and dynamic spectrum management. This work also discusses the emergent behavior of cognitive radio.

12,172 citations

Journal ArticleDOI
TL;DR: This work develops and analyzes low-energy adaptive clustering hierarchy (LEACH), a protocol architecture for microsensor networks that combines the ideas of energy-efficient cluster-based routing and media access together with application-specific data aggregation to achieve good performance in terms of system lifetime, latency, and application-perceived quality.
Abstract: Networking together hundreds or thousands of cheap microsensor nodes allows users to accurately monitor a remote environment by intelligently combining the data from the individual nodes. These networks require robust wireless communication protocols that are energy efficient and provide low latency. We develop and analyze low-energy adaptive clustering hierarchy (LEACH), a protocol architecture for microsensor networks that combines the ideas of energy-efficient cluster-based routing and media access together with application-specific data aggregation to achieve good performance in terms of system lifetime, latency, and application-perceived quality. LEACH includes a new, distributed cluster formation technique that enables self-organization of large numbers of nodes, algorithms for adapting clusters and rotating cluster head positions to evenly distribute the energy load among all the nodes, and techniques to enable distributed signal processing to save communication resources. Our results show that LEACH can improve system lifetime by an order of magnitude compared with general-purpose multihop approaches.

10,296 citations