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Showing 1 to 8 of 8 for “"Spiral Antennas"”.
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Analysis, design, and fabrication of Archimedean spiral antennas
The uses for wideband antennas include wideband measurement systems, spread spectrum communications systems, feeds for reflectors and elements in wideband arrays. Here, wideband antennas are discussed and Archimedean spiral antennas are found to be appropriate elements for use in a new type of …
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Design of an Ultra-Wideband Spiral Antenna for Ground-Penetrating Microwave Impulse Radar Applications
… Radar (MIR) capable of IED detection requires antennas capable of transmitting sub-nanosecond pulses over ultra-wideband (UWB) frequency ranges. This thesis investigates the suitability of a novel MIR antenna for high-accuracy ground-penetrating radar (GPR) applications. Key GPR antenna …
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Low-power dual-band on-body antenna for wireless body sensor networks
… central antenna for WBAN. Five types of helical antennas are proposed in the present thesishaving a dual-frequency operation at 2.45 GHz and 5.8 GHz. The proposed antennas are optimized to maximize the Signal-to-Noise-Ratio (SNR) and, hence, to minimize the BER and the Specific Absorption Rate …
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Investigation, design and implementation of circular-polarised antennas for satellite mobile handset and wireless communications. Simulation and measurement of microstrip patch and wire antennas for handheld satellite mobile handsets and investigations of polarization polarity, specific absorption rate, and antenna design optimization using genetic algorithms.
… design and implement circularly-polarized antennas to be used for handheld satellite mobile communication and wireless sensor networks. Several antennas such as Quadrifilar Spiral Antennas (QSAs), two arm Square Spiral and stripline or coaxially-fed microstrip patch antennas are developed …
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Analysis and solutions for RFID tag and RFID reader deployment in wireless communications applications. Simulation and measurement of linear and circular polarised RFID tag and reader antennas and analysing the tags radiation efficiency when operated close to the human body.
… problems associated with the implementations of antennas RFID Reader and Tag for various applications. In particular, the efficiency of the RFID reader antenna and the detection range of the RFID tag antenna, subject to a small and compact antenna¿s design configuration have been studied. The …
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RF hardware design of a stepped frequency continuous wave ground penetrating radar
… by a PC was assembled. Cavity-backed log spiral antennas were designed and built by the University of Stellenbosch for the specific use of ground penetrating radar. Measurements with the first generation system proved the concept of SFCW GPR and thus a dedicated second generation system …
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Research and Development of Low-Profile, Small Footprint Antennas for VHF-UHF Range Applications
<p>Efficient, but low-profile and small-footprint antennas for VHF-UHF range applications remains an ongoing work. VHF range spans approximately 54 - 88 MHz while UHF roughly ranges from 174 - 890 MHz. The inverse relationship between the physical length and resonant frequency of an antenna, which …
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Design and Analysis of Star Spiral with Application to Wideband Arrays with Variable Element Sizes
… dissertation details the development of the star spiral antenna and demonstrates the advantages of the star spiral when used in a wideband array with variable element sizes. The wideband array with variable element sizes (WAVES) is a multi-octave array that uses different sized circular …