Dr. Jeffrey Pawlan

Pawlan Communications, San Jose CA, USA

An Introduction to Software Defined Radio

Abstract

This lecture will begin with the definition, history and evolution of Software Defined Radio (SDR). RF/microwave engineers will find it clear and understandable because analogies will be made to conventional classic radio systems and components. The lecture will then introduce the concepts of oversampling and undersampling as it applies to SDR. There will be an introduction to the details of correctly driving and implementing an A/D converter as this is one of the important areas that the RF/microwave engineer will be asked to do. There will be an introduction and explanation of the firmware and software portions of SDR and a comparison with state-of-the art conventional analog circuitry will be shown. A live demonstration of SDR will be presented. Software Defined Radio (SDR) is the culmination of advances on several fronts and probably the most significant area of development in radio systems today. The entire worldwide cellular system uses SDR. NASA and the US military communications are now almost exclusively using SDR. Some new automobile radios use SDR to accommodate multiple modulation formats. The role of the RF/microwave engineer in this new technology will be shown so that the audience can adapt and feel that their skills are needed in the evolving field of radio communications

Bio

Dr. Jeffrey Pawlan has been a consultant as owner of Pawlan Communications for 25 years. Prior to that, he had worked for many companies in California in very diverse areas of analog, RF, and microwave design and has been an engineer for 45 years. Some of his work was for NASA projects including the very successful design of the SARSAT/COSPAS search and rescue satellite ground stations. He also taught engineering part-time. Born and raised in the Los Angeles area, he attended UCLA and several other universities. He enjoyed learning many different fields and has 13 years of higher education including a Doctorate degree. He has worked on projects for consumer, industrial, and military applications covering a wide range of the spectrum from LF to 50GHz. In addition to his primary involvement with the MTT society, he is also a member of the UFFC (frequency control) concentrating on low phase noise oscillators and phase noise measurements, a member of the AP-S, and also the Communications Society. He has published several papers and has two patents. He is serving as a member on the IEEE SCV Section ExCom and also is on the Opcom of Region 6. He is a member of two MTT technical committees, MTT-9 and MTT-20. He has been designing RF and microwave hardware for Software Defined Radio uses within instrumentation and military satellite communications since 1984. He has presented talks in many MTT workshops and more than 58 lectures world-wide.

Thursday, November 5, 2015, at 16:00

Room 011, Kitot building

סמינר מחלקתי

School of Mechanical Engineering Seminar
Monday, December 7, 2015 at 15:00
Wolfson Building of Mechanical Engineering, Room 206

Petroleum Reservoir Modeling: Upscaling Flow

with Capillary Heterogeneity Effects

Dr. Avinoam Rabinovich

Department of Energy Resources Engineering Stanford University, Stanford, CA, USA

Reservoir modeling is an area of petroleum engineering focused on characterizing reservoirs and simulating flow associated with injection and production of oil and natural gas. In this talk I will begin with a short overview on reservoir modeling with emphasis on upscaling. Modeling multi-phase flows in reservoirs consists of solving complex non-linear equations. Typically, reservoir scale flow on the order of hundreds of meters are simulated on grids of about a meter in size and computation is therefore very expensive. Furthermore, reservoir properties are spatially variable and subject to uncertainty so that often many different realizations of the geological model are considered. This adds to the computational cost resulting in many cases in unrealistic simulation times. Upscaling is a means of reducing the computational cost by transitioning to larger grid blocks assigned with equivalent properties. A new method for upscaling two-phase flow with strong capillary heterogeneity effects will be presented. This method was tested on a synthetic two-dimensional reservoir model simulating an aquifer injected with CO₂, for possible use in CO₂ sequestration applications.

Another aspect of reservoir modeling is estimation of subsurface properties, e.g., permeability. Recently, interest has grown in characterization using oscillatory pumping tests. New field test results will be presented, in which a periodic pressure signal is generated by pumping and injecting water into an aquifer consecutively and the pressure response is recorded at many points around the source. Hydraulic equivalent properties are then estimated by matching measurements to an analytical solution and values are shown to be in agreement with previous estimates conducted at this site.