الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Demand for devices that can sense motion, orientation, and location is surging, and it runs the gamut from the hottest video games to critical medical technology. With accelerometers and gyroscopes based on microelectromechanical systems (MEMS) : rapidly maturing, that demand is being met. Many of the latest consumer products include one or more MEMS Integrated Circuit (IC) : functions that measure and control factors like movement, position, force, and even temperature. As a result, MEMS ICs not only play a key role in accelerometers and gyroscopes, but also pressure sensors, microphones, timing devices, filters, switches, microdisplays, infrared temperature sensors, and micromotors. MEMS are now becoming quite popular in numerous consumer applications. As a result of the rapidly decreasing costs of MEMS components over the past few years, products that could have used MEMS functionality in the past are now rapidly adopting MEMS. The first part of this thesis proposed a new architectures for cantilevered beam Radio Frequency Microelectromechanical Systems (RF MEMS) : switches. The analyses of the modeling approaches use the MATLAB toolbox for MEMS called SUGAR. SUGAR is used to calculate netlist of a cantilever beam (CLB) : subjected to an external force, static analysis of deflection, display of structure and displacement values. The switching voltage of proposed eight structure for MEMS switches is determined and analyzed for their different configurations and geometrical parameters to achieve maximum frequency response switching at lower driving voltage. The second part , proposes a modification for the phase-locked loop (PLL) : to improve its Performance using two proposals ,the first by improving the charge Pump (CP) : and the second by modulating the voltage controlled oscillator (VCO) : for frequency hopping ,PLL frequency synthesizer suitable for multi-band transceivers is proposed. The multi-band PLL frequency synthesizer uses a switched tuning VCO. The third part of this thesis is the frequency hopping synthesizer ,A multi-band frequency synthesizer is needed to synthesize multiple frequency bands. A multi-band frequency synthesizer must be able to synthesize a wide range of frequencies. The fourth part of this thesis proposes a modified direction-of-arrival (DOA) : estimation algorithm for Smart antenna. In array signal processing, estimation of DOA from multiple sources plays an important role. The modified algorithm is based on Minimum Variance Distortionless Response (MVDR) : algorithm by introducing a new optimization method, aims to maintain array gain in the ‘look direction’, so that the DOA can be estimated correctly using Smart antenna array. To verify the performance of the proposed algorithm, computer simulations are performed and then the results obtained are compared with the MVDR algorithm. The results show that the proposed algorithm outperforms the MVDR algorithm. The proposed schemes avoided estimation failures for any angle of arrival in any region of practical interest in the systems.