Wagdy M.F.,California State University, Long Beach |
Jayaram S.M.,CSULB |
Proceedings of the 2013 10th International Conference on Information Technology: New Generations, ITNG 2013 | Year: 2013
A novel flash fast-locking digital phase-locked loop (DPLL) is presented and behaviorally modeled using Verilog-AMS. The DPLL operation includes two stages: (1) a novel coarse-tuning stage for frequency tracking which employs a flash algorithm leading to a thermometer code as done in flash A/D converters (ADCs) and (2) a fine-tuning stage similar to conventional (classical) DPLLs. The coarse-tuning stage includes an array of frequency comparators, a priority encoder, a digital-to-analog converter (DAC), and control logic including a monostable multivibrator. Verilog-AMS (Smash) is used to design and simulate both the fast-locking DPLL and its classical counterpart. Simulations revealed a lock time improvement (reduction) by a factor of 1.50-3.00 depending on the size of the input frequency hop in favor of the fast-locking DPLL. © 2013 IEEE.
Wagdy M.F.,California State University, Long Beach |
Rao S.S.,CSULB |
Singh K.K.,CSULB |
Ibrahim G.H.,Electronics Research Institute of Egypt
Proceedings of the IEEE International Conference on Electronics, Circuits, and Systems | Year: 2016
Simulations of a receiver using a Super-Regenerative Oscillator (SRO) as a front end, to demodulate 8-PSK Modulated Signals, is presented. The circuit involves a Low Noise Amplifier (LNA) combined with the SRO, for the purpose of current reuse, operating in 402-405 MHz MICS band. Demodulation is done utilizing the phase content of the signal that has been regenerated by the front-end of the receiver (LNA & SRO). The demodulation is achieved without downconverting incoming RF signal into IF band which eliminates the use of a Local Oscillator (LO), a Phase Locked Loop (PLL) or an Analog-to-Digital Converter (ADC). The complete design of the receiver made use of 0.12 μm CMOS technology and pre-layout simulations confirm proper and efficient demodulation of 8-PSK signals. The power consumption of around 175 μW is measured for an input of -80 dBm at a rate of 4Mbps. © 2015 IEEE.
Hefazi H.,CSULB |
Mizine I.,Computer Sciences Corp. |
Schmitz A.,CSULB |
Klomparens S.,Computer Sciences Corp. |
Wiley S.,Computer Sciences Corp.
Naval Engineers Journal | Year: 2010
This paper describes the development and application of a synthesis-level multidisciplinary design and optimization (MDO) method for multihull ships. This method is unique in utilizing advanced multi-objective optimization methods, neural network (NN)-based response surface methods (RSM), and in its broad scope, integrating powering, stability, seakeeping, hullforms definition, structural weights, and cost and payload capacity into a single design tool. This MDO method is developed in the context of a multilevel hierarchy system approach where the results of the synthesis level optimization can be used for subsystem optimization and overall coordination of multilevel design system. NN-based RSM forseakeeping and powering is developed and used in the optimization process. This RSM approach moves the computational cost of such performance evaluations out of the optimization cycle, substantially reduces the optimization cost, and allows for using results of physics-based methods, such as advanced computational fluid dynamics, at the synthesisdesign level of design hierarchy. Details of these methods are delineated and multi-objective optimization results are presented in the form of Pareto optimum solutions for multihull ship concepts such as trimaran sealift support ships and catamaran high-speed connector ships. © 2011, American Society of Naval Engineers.
Robles J.,California State University, Long Beach |
Sguerri M.,California State University, Long Beach |
Rorie R.C.,CSULB |
Vu K.-P.,CSULB |
And 2 more authors.
Proceedings - IEEE International Conference on Robotics and Automation | Year: 2012
In this paper, we present a framework for the integration of force feedback information in a NASA NextGen Volumetric Cockpit Situation Display (CSD). With the current CSD, the user retrieves operational information solely through visual displays and interacts with the CSD tools through using a mouse. The advanced capabilities of the CSD may require complex manipulation of information which may be difficult to perform with input devices found in today's cockpits. Performance with the CSD could benefit from a new user input device and enhanced user feedback modalities that can be operated safely, effectively, and intuitively in a cockpit environment. In this work, we investigate the addition of force feedback in two key CSD tasks: object selection and route manipulation. Different force feedback models were applied to communicate guidance commands, such as collision avoidance and target contact. We also discuss the development of a GUI-based software interface to allow the integration of a haptic device for the CSD. A preliminary user study was conducted on a testbed system using the Novint Falcon force-feedback device. A full experiment, assessing the effectiveness and usability of the feedback model in the CSD, will be performed in the next phase of our research. © 2012 IEEE.