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Low-cost implementation of broadband microwave receivers in Ka-band using multiport structures

IET MICROWAVES ANTENNAS & PROPAGATION 2009年第3期3卷 483-491页

作者： Mirzavand, R. Mohammadi, A. Abdipour, A. Amirkabir Univ Technol Dept Elect Engn Microwave & Wireless Commun Res Lab Tehran 15914 Iran

The authors introduce a new class of the microwave and millimeter wave multiport receivers. These receivers are designed based on a new five-port structure and offer a wide bandwidth. The low-cost implementation is the other advantage of this structure. The numerical and microwave simulations have been conducted to investigate the characteristics of the receiver. In addition, the new five-port receiver has been constructed and measured. The analytical and measurement results are in good agreement with each other. This indicates that the structure can effectively be used as a high-performance and low-cost wideband receiver for broadband applications. As a practical application, the European and North-American local multipoint distribution services band can be covered using this new architecture.

关键词： multiport wideband receiver local multipoint distribution service new buildings measurement result New classes microwave receivers Receivers Extremely high frequencies MICROWAVE broadband

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The System Design of a Global Communications System for Military and Commercial use Utilizing High Altitude Unmanned Aerial Vehicles (UAVs) and Terrestrial local multipoint distribution service (LMDS) Sites

The System Design of a Global Communications System for Mili...

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作者： Banks, Bradley Virginia Tech | University

This thesis proposes the design of the UAV-LMDS communication system for military and commercial use. The UAV-LMDS system is a digital, wireless communication system that provides service using unmanned aerial vehicles (UAVs) flying at 60,000 ft. acting as communication hubs. This thesis provides background information on UAV-LMDS system elements, a financial analysis, theory, link budgets, system component design and implementation issues. To begin the design, we develop link budgets that are used to characterize system parameters. We present detailed antenna designs for the antennas aboard the UAV. We also present communication equipment block diagrams. Included are technical details on military and commercial geostationary satellites used to link transmissions in the system. Implementation issues in the military system are discussed. Mobility and the effects of vegetation in the propagation path are investigated and a co-channel interference study is done. This thesis shows that by using UAVs and LMDS, a viable, broadband, wireless communications system can be created for military and commercial use.

关键词： Unmanned Aerial Vehicles Broadband Communication services Communication System Design LMDS UAV local multipoint distribution service Thesis

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A high-gain 18-32 GHz MMIC driver amplifier for LMDS application

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2000年第4期24卷 237-238页

作者： D'Agostino, S Betti-Berutto, A Poledrelli, C Khandavalli, C Satoh, T Yokoyama, T Kuroda, S Fukaya, J Univ Rome La Sapienza Dept Elect Engn I-00184 Rome Italy Fujitsu Quantum Devices Ltd Atsugi Kanagawa Japan

A high-gain GaAs MMIC driver amplifier for local multipoint distribution service application delivering 32 dBm output power, with associated gain better than 19 dB, has been developed for high-volume production. The MMIC realization consists of a four-stage amplifier integrated in a 2.2 x 1.5 mm(2) single chip on a 28 mu m substrate thickness PHEMT process. (C) 2000 John Wiley & Sons, Inc.

关键词： amplifier MMIC PHEMT local multipoint distribution service

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Medium range terrestrial propagation study at 28 GHz

Medium range terrestrial propagation study at 28 GHz

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Conference on Wireless Technologies and Systems - Millimeter-Wave and Optical

作者： Marin, S Myers, W Burt, D Bosch Telecom Inc Dallas TX 75265 USA

ISBN: (纸本)0819426652

Millimeter wave communications systems experience variation in propagation due to rain and other causes. This paper describes a 7.25 km experimental link at 28 GHz ire Dallas, Texas used for studying propagation effects. Received signal data was collected at 30 second intervals over an 5 month period. The data shows the effects of clear air variation and rain fade loss. Weather data including rain rate was also collected at 1 minute intervals at the transmit and receive sites. During the observation period, rain rates greater than 38 mm/hr and fades greater than 44 dB occurred less than 0.01% of the time. During rain fades, the received signal varied at a maximum rate of 0.3 dB/sec. Rain fades of 20 dB or less extended for duration of 40 minutes. During clear days, signal variations of up to 7 dB occurred including enhancement and attenuation. The standard deviation of clear air fading was about 1 dB.

关键词： millimeter wave 28 GHz Ka Band terrestrial propagation rain fade local multipoint distribution service

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Technology of fixed wireless access

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TELECOMMUNICATIONS POLICY 1997年第5期21卷 437-450页

作者： Trinkwon, D NO TELECOM NORTEL FIXED WIRELESS ACCESSMARKET DEVRICHARDSONTX 75082 USA

The ability of different wireless technologies to co-exist within a single geographic area, owned and operated by different service providers with relatively simple sharing arrangements for common infrastructure is one of the key aspects that makes wireless technology a valuable addition to the universal service concept--in fact it can change the fundamental assumptions embodied within traditional approaches to universal service, This paper examines the challenge operators and regulators have in providing telecommunications services, especially to smaller communities, and the role that Wireline Equivalent Fixed Wireless Access systems can play. (C) 1997 Elsevier Science Ltd.

关键词： ADPCM Adaptive Pulse Code Modulation ADSL Asynchronous Digital Subscriber Line AMPS Advanced Mobile Phone System/service ANI Automatic Number Identification CATV Community Antenna Television CITEL Inter-American Telecommunications Commission CITI Columbia Institute for Teleinformation CPE Customer Premise Equipment DTMF Dual Tone Multifrequency FDMA Frequency Division Multiple Access FWA Fixed Wireless Access GSM General service Mobile ISDN Integrated services Digital Network ISDN BRI ISDN Basic Rate Interface ISDN PRI ISDN Primary Rate Interface LAN local Area Network LEC local Exchange Carrier LMDS local multipoint distribution service LNP local Number Portability MMDS Multichannel multipoint distribution service MOS Mean Opinion Score OA&M Operations Administration and Maintenance OAM&P Operations Administration Maintenance and Planning PACS Personal Access Communications System PBX Private Branch Exchange PCM Pulse Code Modulation PCS Personal Communications service PHS Personal Handi-phone System POTS Plain Old Telephone service PSTN Public Switched Telephone Network SOHO Small Office Home Office SONET Synchronous Optical Network SS#7 Signaling System Number 7

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