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Full-Text Articles in Engineering
Reduction Of Peak To Average Power Ratio In Ofdm And Ofdm-Cdma System, Jie Cheng
Reduction Of Peak To Average Power Ratio In Ofdm And Ofdm-Cdma System, Jie Cheng
Theses
High Peak to Average Power Ratio is a main problem in Orthogonal Frequency Division Multiplexing(OFDM) system and Orthogonal Frequency Division Multiplexing -Code Division Multiple Access (OFDM-CDMA) system. Considering a compensated High Power Amplifier(HPA), in order to keep linearity for amplification, Input Back-Off(IBO) of the HP-A, has to be increased for handling a high PAPR. Higher 1130 will make HPA less efficient. Additionally, a signal with high PAPR will suffer clipping when PAPR is larger than 1130 of the HPA. Clipping can cause the distortion of the signal and deteriorate the performance of the system. Reduction of PAPR is a main …
Phase Tunability In A Conductor Backed Coplanar Waveguide Patch Antenna, Idan Mandelbaum
Phase Tunability In A Conductor Backed Coplanar Waveguide Patch Antenna, Idan Mandelbaum
Theses
Traditionally beam steering in phase array antenna systems is achieved using tunable phase shifters or switched feed networks. Here, a tunable patch antenna element is suggested as a novel alternative to a combination of a radiating element and a phase shifter. A conductor backed coplanar waveguide patch antenna is chosen due to its suitability to mounted external tuning elements, using varactor diodes. Limited types of lumped tuning circuits, using varactor diodes, have been tested, though a lumped as well as distributed tuning is feasible in the chosen antenna configuration. Approximate analytical models for coplanar waveguide patch antennas with finite ground …
Programmable Latching Probe Microstructures For Wafer Testing Applications, Salima Taifa Sadeq
Programmable Latching Probe Microstructures For Wafer Testing Applications, Salima Taifa Sadeq
Theses
The objective of this thesis is to design a programmable wafer testing array on a single chip based on micro electromechanical systems (MEMS) and VLSI. The wafer-scale integration in this thesis is a programmable array of test probes that are used for engineering test of VLSI and ULSI silicon integrated circuits at the wafer level. This consists of two subsystems (1) the VLSI address circuits used for addressing and controlling the MEMS on the chip and (2) the latching probe MEMS microstructure array that actuates into position for testing VLSI wafers. Each of the subsystems have been designed, analyzed and …
Bounded Beam Wave Pulse Propagation And Scattering In Random Media Based On The Radiative Transfer Theory Using 2-D Gauss Quadrature Formula, Sheng-Kai Hu
Theses
The scalar time-dependent equation of radiative transfer is used to develop a theory of bounded beam wave narrow band pulse propagation and scattering in a medium characterized by many random discrete scatters, which scatters energy strongly in the forward scattering direction. Applications include the scattering of highly collimated millimeter waves in vegetation and optical beams in the atmosphere. The specific problem analyzed is that of a periodic sequence of Gaussian shaped pulses normally incident from free space onto the planar boundary surface of a random medium half-space, such as a forest, that possesses a scatter (phase) function consisting of a …
Experimental Ion Implantation System For Decaborane Ions, Vijay Babaram
Experimental Ion Implantation System For Decaborane Ions, Vijay Babaram
Theses
Future generations of Si technology will require ultra shallow junctions (tens of nm) in the drain and source regions of MOS transistors. Fabrication of such shallow p-type junctions requires implantation of boron at ultra low energies (< 1 keV), below the limits of standard ion implantation technology. A proposed solution involves implantation of B10Hx+ ions in which boron atoms carry less than 10% of the beam energy.
This thesis is a part of the feasibility study of this new technology. An experimental ion implantation system was designed and built at Ion Beam and Thin Film Lab, NJIT. The system was tested and the mass analyzing magnet was calibrated using argon ions. Decaborane ions, …
Editing Mpeg2 Video In Compressed Domain, Ren Egawa
Editing Mpeg2 Video In Compressed Domain, Ren Egawa
Theses
As MPEG2 becomes the heart of most digital video applications, the need to edit an MPEG2 bitstream video in compressed domain has increased. To realize this need, two major technical issues must be resolved: decoder buffer and segment extraction.
In the decoder buffer issue, the edited stream must ensure that the buffer would not overflow or underfiow as the result of the editing. This thesis invented a mathematical model that could describe the editing task and predict the editing effect on the buffer. Based on this model, the thesis then built a method to edit a stream safely. This method …