require the design of high-quality sensor devices and practical algorithms for exchanging spectrum-monitoring data between cooperating communications nodes. Systems that feature multiple-input/multiple-output capabilities will direct transmissions along complex multipath components—thereby accounting for reflections of signals from objects such as buildings and vehicles — and away from other potentially interfering radios.
A fully functional cognitive radio system will be smart enough to sense the local RF “scene”, to choose the radio band, mode and service it needs as well as the SDR upload connections to the selected band and mode. It will then direct its transmission energy toward the intended receiver while minimizing interference with other radios, including cognitive ones. Thus, it will display a high level of spectrum etiquette and connect the user securely and privately.
The accuracy of such operations could be improved by the development of three-dimensional computer representations of the full local cityscape stored on gigabyte hard drives, which would be accessed wirelessly as needed.
Just as the emergence of cell-phone technology has led to wide social and business consequences, cognitive radio's adoption will induce similar changes as advanced devices exploit the wireless Web to displace now traditional cell phones. The growth of cognitive radio will take some time to occur, but the effect on all our lives will be significant.
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CONTENTS |
|
Введение....................................................................................................... |
3 |
Lesson 1......................................................................................................... |
5 |
Text 1A. Electromagnetic waves and antenna basics ................................... |
5 |
Text 1B. Antenna polarisation .................................................................... |
8 |
Text 1C. Antenna feed impedance ............................................................ |
12 |
Grammar exercise № 1............................................................................. |
14 |
Lesson 2....................................................................................................... |
16 |
Text 2A. Antenna resonance and bandwidth.............................................. |
16 |
Text 2B. Antenna bandwidth .................................................................... |
18 |
Grammar exercise № 2............................................................................. |
20 |
Lesson 3....................................................................................................... |
23 |
Text 3A. Why Digital Transmission?........................................................ |
23 |
Text 3B. Fidelity of reproduction and error control digital transmission..... |
25 |
Text 3C. The satellite channel................................................................... |
27 |
Grammar exercise № 3............................................................................. |
29 |
Lesson 4....................................................................................................... |
31 |
Text 4A. Adaptive antenna arrays............................................................. |
31 |
Text 4B.................................................................................................... |
34 |
Text 4C. Benefits and applications of adaptive antenna arrays................... |
36 |
Grammar exercise № 4............................................................................. |
39 |
Supplementary texts...................................................................................... |
41 |
Plasma antenna technology....................................................................... |
41 |
Cognitive Radio ....................................................................................... |
43 |
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Учебное издание
Стасенко Ирина Валентиновна Куликова Маргарита Владимировна Сафарова Ирина Григорьевна
ОБУЧЕНИЕ ЧТЕНИЮ ЛИТЕРАТУРЫ НА АНГЛИЙСКОМ ЯЗЫКЕ ПО СПЕЦИАЛЬНОСТИ
«РАДИОЭЛЕКТРОННЫЕ СИСТЕМЫ И УСТРОЙСТВА»
Корректор Е.К. Кошелева
Компьютерная верстка С.А. Серебряковой
Подписано в печать 18.01.2012. Формат 60×84/16. Усл. печ. л. 2,79. Тираж 500 экз. Изд. № 21. Заказ
Издательство МГТУ им. Н.Э. Баумана. Типография МГТУ им. Н.Э. Баумана. 105005, Москва, 2-я Бауманская ул., 5.
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