Dr. Richard Snyder of RS Microwave

What’s rare, critically important, and very expensive? No, it’s not gold, platinum nor diamonds…it is SPECTRUM! No matter how you code, point, amplify or share it, transmission of information still must utilize some spectrum, and there is only so much to go around. Every Hz is precious, so the political and economic wars between parties competing for the right to put their bits of data into tiny bits of spectrum are fierce indeed. Communication between people will always be important, but communication between computers and systems are critical to maintaining our modern life. It is necessary to construct boundaries of some sort between these vast and competing flows of data, and it is safe to say that without modern filter technology providing these barriers our society could easily drown in these tsunami waves of critical information. (http://money.cnn.com/2011/12/29/technology/white_space_spectrum/index.htm?hpt=hp_t3) The delimiters of modern filter technology are performance, reliability, size and cost. Keeping in mind that spectrum is more expensive than the systems themselves, performance becomes of critical importance at the system level, with size also significant because many systems are densely packed. At the component, or “board” level, cost becomes more significant because many filters are used and thus overall cost depends on the economics of filter production. Reliability (i.e. MTBF) is a major contributor to the “cost”, because post-deployment repair of systems and internal board-level components is labor-intensive and thus a longterm (unintended) and thus potentially expensive, part of the budget. With performance and size typically a coupled pair of operators, modern filter design works towards putting more performance into the same size, or equivalent performance into a smaller size. Over the last three decades, technological and topological improvements have made possible both results. With the development of simulation tools enabling prediction of interactions not only between isolated circuit elements, but between physical structures, it has been found possible to use the interactions to provide selectivity improvements. This can reduce the number of physical resonating elements required to produce a proscribed ratio of stopband to passband, and thus reduce the physical size for a given performance level. Alternatively, more coupled resonances can be packaged into a given volume than if the interactions must be prevented (rather than utilized), and so more performance is possible in a given package due to the use of modern simulation combined with modern, high-precision manufacturing techniques. Contributing to the technological improvements are new materials, used in composite assemblies, to reduce the sensitivity of filters to temperature and humidity, thus reducing what is known as “guardband”, the necessary overdesign to allow for drift while maintaining passband and stopband characteristics, and enhancing RF power handling capability. The new composites also avoid the use of temperature stable steel alloys, and thus reduce weight and cost. When considering topological improvements, one finds that the concept of feed forward (when applied to filters, called “cross-coupling) allows a reduction in the internal component count and thus in size, for a given performance. As might be expected, the alternate, i.e. more performance in the same size, is also possible. The phrases “non-resonating nodes” and “non-resonating modes” are relatively recent, but both have added to the arsenal of topologies and design strategies available to today’s filter designers. In this talk, we will cover both technology and topology. In the technological area, we will discuss materials, environmental compensation, manufacturing, reliability and design simulation methods, while in the area of network topology, the talk will include discussion of nodes, modes, frequency dependent coupling elements, non-commensurate coupled sections, multiplexers, active elements, switched combinations and tunable structures, with graphic examples of filters and performance.

Biography: Dr. Richard V. Snyder is President of RS Microwave (Butler, NJ, USA), author of 79 papers, three book chapters and holds 19 patents. His interests include E-M simulation, network synthesis, dielectric and suspended resonators, high power notch and bandpass filters and active filters. He received his BS, MS and PhD degrees from Loyola-Marymount, USC and PINY. Dr. Snyder served the IEEE North Jersey Section as Chairman and 14 year Chair of the MTT-AP chapter. He chaired the IEEE North Jersey EDS and CAS chapters for 10 years. He twice received the Region 1 award. In January 1997 he was named a Fellow of the IEEE and is now a Life Fellow. In January 2000, he received the IEEE Millennium Medal.
Dr. Snyder served as General Chairman for IMS2003, in Philadelphia. He was elected to ADCOM in 2004, and was the 2010 President-Elect for the MTT-S. Within the ADCOM, he served as Chair of the Standards committee, Chair of the TCC and Liaison to the EuMA. He served as an MTT-S Distinguished Lecturer, from 2007-2010, as well as a member of the Speakers Bureau. He was an Associate Editor for the IEEE Transactions on Microwave Theory and Techniques, responsible for most of the filter papers submitted during the period 2007-2010. He is a member of the American Physical Society, the AAAS and the New York
Academy of Science. He was the MTT-S President for 2011. Also a reviewer for IEEE-MTT publications and the MWJ, Dr. Snyder teaches and advises at the New Jersey Institute of Technology He is a Visiting Professor at the University of Leeds, in the U.K. He served 7 years as Chair of MTT-8 and continues in MTT-8/TPC work. He previously was Chief Engineer for Premier Microwave.

Email:

Address:President, RS Microwave, Butler, New Jersey, United States

Dr. Richard Snyder of RS Microwave

Biography:

Email:

Address:Butler, New Jersey, United States