Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports
Title Scientific and Technical Aerospace Reports PDF eBook
Author
Publisher
Pages 1282
Release 1982
Genre Aeronautics
ISBN

Download Scientific and Technical Aerospace Reports Book in PDF, Epub and Kindle

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

British Piston Aero-engines and Their Aircraft

British Piston Aero-engines and Their Aircraft
Title British Piston Aero-engines and Their Aircraft PDF eBook
Author Alec Lumsden
Publisher Crowood Press (UK)
Pages 342
Release 1994
Genre History
ISBN

Download British Piston Aero-engines and Their Aircraft Book in PDF, Epub and Kindle

This is a record of more than 250 basic types of British aero engine built between 1909 and 1949. In some 900 variants, they powered 300 different types of aircraft both civil and military. This volume gives a cross-reference of all aircraft engine types, variants and the aircraft they powered.

The Woman and the Car

The Woman and the Car
Title The Woman and the Car PDF eBook
Author Dorothy Levitt
Publisher
Pages 216
Release 1909
Genre Automobile driving
ISBN

Download The Woman and the Car Book in PDF, Epub and Kindle

International Journal of Surface Engineering and Interdisciplinary Materials Science (IJSEIMS).

International Journal of Surface Engineering and Interdisciplinary Materials Science (IJSEIMS).
Title International Journal of Surface Engineering and Interdisciplinary Materials Science (IJSEIMS). PDF eBook
Author J. Paulo Davim
Publisher
Pages
Release 2015
Genre Materials science
ISBN 9781466680524

Download International Journal of Surface Engineering and Interdisciplinary Materials Science (IJSEIMS). Book in PDF, Epub and Kindle

Massive MIMO

Massive MIMO
Title Massive MIMO PDF eBook
Author Hien Quoc Ngo
Publisher Linköping University Electronic Press
Pages 69
Release 2015-01-16
Genre
ISBN 9175191474

Download Massive MIMO Book in PDF, Epub and Kindle

The last ten years have seen a massive growth in the number of connected wireless devices. Billions of devices are connected and managed by wireless networks. At the same time, each device needs a high throughput to support applications such as voice, real-time video, movies, and games. Demands for wireless throughput and the number of wireless devices will always increase. In addition, there is a growing concern about energy consumption of wireless communication systems. Thus, future wireless systems have to satisfy three main requirements: i) having a high throughput; ii) simultaneously serving many users; and iii) having less energy consumption. Massive multiple-input multiple-output (MIMO) technology, where a base station (BS) equipped with very large number of antennas (collocated or distributed) serves many users in the same time-frequency resource, can meet the above requirements, and hence, it is a promising candidate technology for next generations of wireless systems. With massive antenna arrays at the BS, for most propagation environments, the channels become favorable, i.e., the channel vectors between the users and the BS are (nearly) pairwisely orthogonal, and hence, linear processing is nearly optimal. A huge throughput and energy efficiency can be achieved due to the multiplexing gain and the array gain. In particular, with a simple power control scheme, Massive MIMO can offer uniformly good service for all users. In this dissertation, we focus on the performance of Massive MIMO. The dissertation consists of two main parts: fundamentals and system designs of Massive MIMO. In the first part, we focus on fundamental limits of the system performance under practical constraints such as low complexity processing, limited length of each coherence interval, intercell interference, and finite-dimensional channels. We first study the potential for power savings of the Massive MIMO uplink with maximum-ratio combining (MRC), zero-forcing, and minimum mean-square error receivers, under perfect and imperfect channels. The energy and spectral efficiency tradeoff is investigated. Secondly, we consider a physical channel model where the angular domain is divided into a finite number of distinct directions. A lower bound on the capacity is derived, and the effect of pilot contamination in this finite-dimensional channel model is analyzed. Finally, some aspects of favorable propagation in Massive MIMO under Rayleigh fading and line-of-sight (LoS) channels are investigated. We show that both Rayleigh fading and LoS environments offer favorable propagation. In the second part, based on the fundamental analysis in the first part, we propose some system designs for Massive MIMO. The acquisition of channel state information (CSI) is very importantin Massive MIMO. Typically, the channels are estimated at the BS through uplink training. Owing to the limited length of the coherence interval, the system performance is limited by pilot contamination. To reduce the pilot contamination effect, we propose an eigenvalue-decomposition-based scheme to estimate the channel directly from the received data. The proposed scheme results in better performance compared with the conventional training schemes due to the reduced pilot contamination. Another important issue of CSI acquisition in Massive MIMO is how to acquire CSI at the users. To address this issue, we propose two channel estimation schemes at the users: i) a downlink "beamforming training" scheme, and ii) a method for blind estimation of the effective downlink channel gains. In both schemes, the channel estimation overhead is independent of the number of BS antennas. We also derive the optimal pilot and data powers as well as the training duration allocation to maximize the sum spectral efficiency of the Massive MIMO uplink with MRC receivers, for a given total energy budget spent in a coherence interval. Finally, applications of Massive MIMO in relay channels are proposed and analyzed. Specifically, we consider multipair relaying systems where many sources simultaneously communicate with many destinations in the same time-frequency resource with the help of a massive MIMO relay. A massive MIMO relay is equipped with many collocated or distributed antennas. We consider different duplexing modes (full-duplex and half-duplex) and different relaying protocols (amplify-and-forward, decode-and-forward, two-way relaying, and one-way relaying) at the relay. The potential benefits of massive MIMO technology in these relaying systems are explored in terms of spectral efficiency and power efficiency.

Street TurbochargingHP1488

Street TurbochargingHP1488
Title Street TurbochargingHP1488 PDF eBook
Author Mark Warner
Publisher Penguin
Pages 480
Release 2006-06-06
Genre Transportation
ISBN 1101142367

Download Street TurbochargingHP1488 Book in PDF, Epub and Kindle

Transform an average car or truck into a turbocharged high performance street machine. A handbook on theory and application of turbocharging for street and high-performance use, this book covers high performance cars and trucks. This comprehensive guide features sections on theory, indepth coverage of turbocharging components, fabricating systems, engine building and testing, aftermarket options and project vehicles.

International Aerospace Abstracts

International Aerospace Abstracts
Title International Aerospace Abstracts PDF eBook
Author
Publisher
Pages 940
Release 1997
Genre Aeronautics
ISBN

Download International Aerospace Abstracts Book in PDF, Epub and Kindle