• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 15
  • 3
  • 1
  • Tagged with
  • 21
  • 13
  • 12
  • 11
  • 9
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

MINIATUIRIZED ULTRA-WIDEBAND ANTENNAS FOR WIRELESS COMMUNICATIONS

Gorla, Hemachandra Reddy reddy 01 June 2021 (has links) (PDF)
Wireless communication is part of our daily life in several applications, such as cell phones, wireless printers, sensors, etc. Each wireless device requires at least one antenna to communicate with other devices. In 2002, Federal Communications Commission (FCC) assigned a frequency spectrum from 3.1 GHz to 10.6 GHz for ultra-wideband communications. Several narrowband antennas require to cover the entire range. Unlike narrowband antennas, ultra-wideband antennas need to cover the wide frequency band. This research mainly focuses on physically small antenna designs. The first antenna discussed in this dissertation is a dual, triple trident antenna with dimensions 24 mm × 28 mm × 0.785 mm, which will operate from 3 GHz to 12.15 GHz [58]. The first antenna consists of six tridents symmetrical along the vertical direction. The second antenna design is a novel rectangular ring ultra-wideband antenna [59]. Large antennas operate for low frequency, and small antennas work for high frequency. The number of rings increased in wideband antenna to 9 from 4 to check the design methodology. The rectangular ring ultra-wideband antenna has dimensions 24 mm × 26 mm × 1.52 mm. This antenna operates from 3.12 GHz to 12.85 GHz. The third antenna design is an ultra-wideband dual square trident planar antenna. This antenna’s overall size is 26 mm × 24 mm × 1.56 mm [60]. This antenna has impedance bandwidth from 3.65 GHz to 12.50 GHz. The fourth antenna design is an ultra-wideband antenna with a band notch from 5.05 GHz to 5.9 GHz [61]. This antenna consists of two tridents and two split-ring resonators along the microstrip feed line. The overall size of this antenna 26 mm ×24 mm × 1.53mm. Simulations are carried out using the CST microwave studios® to analyze the antenna performance. Experiments are conducted to verify the simulated results using vector network analyzers for impedance and anechoic antenna chamber for radiation characteristics of the antenna. All four antennas are excellent for the wireless device due to their compact size and planar designs.
2

What is the Trident for? Nuclear Deterrence and the Role of British Nuclear Weapons

Ritchie, Nick January 2008 (has links)
Yes / This report supports the second in a series of briefings on Trident to be published during 2007 and 2008 as part of the Bradford Disarmamenet Research Centre's programme on Nuclear-Armed Britain: A Critical Examination of Trident Modernisation, Implications and Accountability.
3

Trident: The Deal Isn't Done - Serious Questions Remain Unanswered

Ritchie, Nick January 2007 (has links)
Yes / This briefing paper is the first in a series to published through 2007 and 2008 as part of the Bradford Disarmament Research Centre¿s programme on ¿Nuclear-armed Britain: A Critical Examination of Trident Modernisation, Implications and Accountability¿. The programme has been generously funded by the Joseph Rowntree Charitable Trust. / Joseph Rowntree Charitable Trust
4

Trident and British Identity: Letting go of Nuclear Weapons

Ritchie, Nick January 2007 (has links)
Yes / This briefing paper is the third in a series to be published during 2007 and 2008 as part of the Bradford Disarmament Research Centre¿s programme on Nuclear-Armed Britain: A Critical Examination of Trident Modernisation, Implications and Accountability. / Joseph Rowntree Charitable Trust
5

Facts about Trident

Ritchie, Nick January 2008 (has links)
Yes
6

A doctrine of 'minimum deterrence'

Ritchie, Nick January 2008 (has links)
Yes
7

Trident decision timeline

Ritchie, Nick January 2008 (has links)
Yes
8

Trident and Scotland

Ritchie, Nick January 2008 (has links)
Yes
9

A Nuclear Family: Britain, America, and NATO Rearmament during the Late Cold War

Clifton, James A. January 2017 (has links)
Thesis advisor: James E. Cronin / This dissertation examines British nuclear policymaking during the late 1970s and early 1980s with a focus on its political implications. Highlighting the important link between nuclear politics and alliance coordination, the dissertation demonstrates that at a time of increased Alliance disunity (over Vietnam, détente, etc.) NATO policymakers achieved a broad consensus on theater nuclear policy that in effect stabilized the Alliance against the crises of the 1970s. The dissertation focuses especially on the U.K.’s role in this; British policymakers’ unique ability to mediate between the U.S. and continental Europe contributed enormously to the success of NATO in this period. Taking the British decision to update its strategic nuclear weapons and the coterminous debates in NATO over theater nuclear weapons, carried out against the backdrop of heightened public opposition and debate, it argues that nuclear politics played an integral role in structuring alliances and that this recalibration not only precipitated the end of the Cold War, but also ensured the Alliance’s post-Cold War viability. This research revises our understanding of the Cold War. This dissertation demonstrates that the Cold War, traditionally regarded as a bipolar conflict between superpowers, was often waged through alliances and that the policy preferences of lesser alliance partners mattered tremendously. The dissertation, furthermore, provides evidence for the way in which British policymakers retained an unexpected and disproportionate influence for the U.K. in world affairs—via their ability to successfully mediate within NATO
10

Trident and America

Ritchie, Nick January 2008 (has links)
Yes

Page generated in 0.0402 seconds