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 20 of 22 for “"Adaptive Antenna"”.
-
Interference Mitigation by Reconfigurable Adaptive Antenna Array
Antenna arrays play an important role in diverse application areas, such as target detection and direction of arrival (DOA) estimation to list a few. Traditional receiver structures with a fixed array configuration are either inefficient due to array redundancies or may incur significant …
-
Adaptive antenna systems for mobile broadband communications
… thrust in wireless communications is the use of adaptive antennas at the transceivers, along with the associated advanced array signal processing, to improve cell coverage, link quality and system capacity. This dissertation first provides a framework of adaptive antenna systems for wireless …
-
Adaptive Antenna Arrays Applied to Position Location
… wireless channel must be developed. The use of adaptive antenna arrays is one area that shows promise for improving capacity of wireless systems and providing improved safety through position location capabilities. These arrays can be used for interference rejection through spatial filtering, …
-
Blind adaptive antenna arrays for mobile communications
Adaptive antenna arrays have tremendous potential for increasing the capacity of mobile communications, by reducing co-channel interference, multipath, and noise. Blind adaptive algorithms, that is, algorithms which do not require a training sequence, are investigated and compared in this study. …
-
Adaptive Antenna Arrays for Satellite Personal Communication Systems
… overall capacity. To overcome this problem, adaptive antenna arrays on handheld terminals are proposed. This technique is believed to be better than omni-directional antennas which radiate in all directions. Adaptive antenna arrays have the ability to adapt to the changing environment and …
-
An adaptive antenna integrated with automatic gain control for a receiver front end
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.
-
Null Depth Trade Off for Output Power Reduction in a Downlink Adaptive Antenna Array
… are known to the basestation. However, downlink adaptive arrays use additional power when they are required to include null steering in their beam patterns. This excessive transmitted power reduces the effective antenna gain, increases interference in other directions and has implications on the …
-
Application of smart antennas to wideband code division multiple access : the uplink performance
Adaptive antenna arrays have recently been introduced to cope with the high capacity required by the 3rd generation (3G) wireless communications systems. As adaptive antenna arrays focus narrow high gain beams towards the desired user and nulls towards interferers, both coverage and capacity of the …
-
Analysis and Development of Blind Adaptive Beamforming Algorithms
… for the development and analysis of blind adaptive algorithms. An adaptive algorithm is said to be 'blind' if it does not require a known training sequence. The main focus is on application of these algorithms to adaptive antenna arrays in mobile radio communications. Adaptive antenna …
-
Simulation of Adaptive Array Algorithms for OFDM and Adaptive Vector OFDM Systems
… intersymbol interference (ISI). Deploying an adaptive antenna array at the receiver can help separate the desired signal from interfering signals which originate from different spatial locations. This enhancement of signal integrity increases system capacity. In this research, we apply …
-
Simulation of Adaptive Array Algorithms for CDMA Systems
… to improve spectrum utilization. The CDMA and adaptive antenna array are two approaches that shows real promise for increasing spectrum efficiency. In this research, we investigate the performance of different blind adaptive array algorithms in the CDMA systems. Two novel algorithms, …
-
The Application of Advanced Operator Genetic Algorithms to Electromagnetic Optimization Problems
… optimization of several measures of merit of antenna arrays. Domain-decomposition genetic algorithms are introduced and applied to the optimization of E-plane microwave filters and frequency selective surfaces. Domain decomposition, the technique of breaking a given problem into parts and …
-
Beamforming for MC-CDMA
… This research work investigates multi-antenna receivers for OFDM and MC-CDMA systems; specifically this works investigates adaptive antenna algorithms for MC-CDMA for very different channel conditions. Frequency domain beamforming is studied in this research predominantly through …
-
Analysis of CDMA cellular radio systems employing adaptive antennas
… (CDMA) cellular communication systems employing adaptive antennas at the base station. First, a simple analysis is presented which shows that significant improvements in performance can be obtained by using directional antennas in the mobile-to-base station link of CDMA cellular radio systems. …
-
Techniques and adaptation algorithms for direct-sequence spread-spectrum CDMA single-user detection
… are explained with a common approach using an adaptive antenna array perspective and noting that single-user detectors exploit spectral redundancy, while adaptive arrays exploit spatial redundancy. Commonly used trained adaptation algorithms for single-user detection are first presented, and …
-
The Impact of Antenna and RF System Characteristics on MIMO System Capacity
… spectral efficiency through the use of multiple antennas at the transmitting and receiving nodes. Such multiple-input multiple-output (MIMO) systems show promise for dramatic performance gains over their single-antenna counterparts. However, MIMO system performance is influenced by many different …
-
Smart Antennas & Power Management in Wireless Networks
… In this thesis work I propose to the use smart antenna technology and a power management scheme in the wireless ad-hoc networks to increase the network capacity in terms of throughput, number of simultaneous communication and to lower the average transmit power and consequently co-channel …
-
Design And Analysis Of Adaptive And Reconfigurable Antennas For Wireless Communication
… a tremendous increase in the number of antennas onboard, on the ground, and in orbital space. This places a burden due to the confined volume and limited weight requirements especially in space applications. The reconfigurable antenna is a promising and exciting new type of antenna, …
-
Cross-Layer Optimization: System Design and Simulation Methodologies
… in wireless communication technologies, such as adaptive modulation and adaptive antenna algorithms, demand a cross layer perspective to this problem in order to provide a sufficient level of fidelity. However, a full simulation of both layers often results in excessively burdensome simulation …
-
Contribution to the characterization and evaluation of multiple antenna systems for communications: prototyping, propagation and antenna perspective
… opening new options for signal processing for antenna arrays. The main objective of this thesis has been to investigate the possibilities for radiocommunication systems that are based on the use of multiple antennas to take advantage of the available spatial diversity in the channel. Moreover, …
Page 1 of 2