Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 11 of 11 for “"Active antenna"”.
-
Wideband active antenna cancellation
There exists a simultaneous transmit and receive antenna system where the transmitted signal is creating wideband interference of the receiver. To resolve this interference problem, the isolation between the transmit antenna and the receive antenna must be increased. This thesis analyzes and …
-
Non-Radiative Calibration of Active Antenna Arrays
Antenna arrays offer significant benefits for modern wireless communication systems but they remain difficult and expensive to produce. One of the impediments of utilising them is to maintain knowledge of the precise amplitude and phase relationships between the elements of the array, which are …
-
Active Antenna Bandwidth Control Using Reconfigurable Antenna Elements
Reconfigurable antennas represent a recent innovation in antenna design that changes from classical fixed-form, fixed-function antennas to modifiable structures that can be adapted to fit the requirements of a time varying system. Advances in microwave semiconductor processing technologies have …
-
Reduction of a Radar Cross Section Using Active Antenna Elements
… and a radiated signal that emanates from an antenna mounted on the structure. A canonical system model consisting of a sensor, feed network, and radiating element is analyzed, and results that show that under limited conditions an effective radar cross section reduction is possible. That is, …
-
Development of Integrated "Chip-Scale" Active Antennas for Wireless Applications
… data networks (WLANs). Integrated microstrip antennas coupled directly to the RF electronics, offer potential advantages of low cost, reduced parasitics, simplified assembly and design flexibility compared to systems based on discrete antennas. However, the size of such antennas is governed by …
-
Architecture and Design Considerations of Active Antennas on Space Based Platforms
The design of antennas for space-based applications requires that particular attention be paid to various requirements imposed on the design by the space environment. Additional requirements are driven by the platform on which the antenna will be hosted as well as by the intended use of the …
-
Photonic generation of microwave signals : a quantum dot mode locked laser as a microwave source
… as -6dBm without any further amplification. An active antenna element was connected to the laser to transmit the generated microwave signal. In addition, the injection locking of the laser to an external source was studied and demonstrated, as a way to increase the stability of the output …
-
Absolute Flux Density Measurement and Associated Instrumentation for Radio Astronomy below 100 MHz
… also reports new measurements of the antenna temperature due to the diffuse Galactic background between 30-78 MHz, addressing a paucity of existing measurements in this band. These measurements are relevant especially in the context of contemporary interest in radio astronomy and 21 cm …
-
Rectangular Waveguide Filled with Uniaxial Medium and Negative Resistance Enhanced Composite Right/Left-Handed Transmission Line
… by an example of high-directivity leaky-wave antenna (LWA). In contrast to the conventional CRLH unit cell with via terminated stubs, the NR-CRLH unit cell is designed with negative-resistance (NR) terminated stub that compensates the power loss from the orthogonal direction with respect to …
-
On iterative low-complexity algorithm for optimal antenna selection and joint transmit power allocation under impact pilot contamination in downlink 5g massive MIMO systems
… Meanwhile, an increase in the number of antenna arrays at BSs resulted in greater power consumption due to the increased number of radio-frequency (RF) chains, which could not be neglected and became a technical challenge. Achievable high data rate in massive MIMO, depended on quality of …
-
Exploration of liquid crystal polymer packaging techniques for rf wireless systems
… realization of highly integrated phased-array antenna systems.