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This article provides a perspective on upcoming IMS power amplifier papers and the potential impact of different papers on the field.

This article describes the need for a large-signal measurement system that integrates the measurement of large-signal parameters and an active harmonics source/load pull system to facilitate a first-pass power amplifier design process.

In the beginning, life was simple, life was analog. One radio occupied a single piece of spectrum and the bandwidth of that spectrum was proportional to the amplitude or bandwidth of the information being transmitted. Then, some time in the last quarter of the twentieth century, commercial radio went digital.

In today’s challenging economic times, capital budgets and costly in-house capabilities are being reduced at many companies. For the sake of the long term health of the industry, we all hope this is a short-term trend. The fact is that RF and microwave characterization equipment and in-house modeling capabilities are cost centers at companies not in the business of providing directly related services to their customers. Moreover, to be effective at detailed RF characterization and modeling, a team of experts need to be retained to cover the spectrum of characterization measurements or custom models required for new product designs. Whether you are a circuit designer or a component, device or IC supplier outsourcing some of your measurement and modeling requirements to a company that specializes in RF measurement and modeling services may prove to be a cost effective way to get your job done and satisfy customer needs.

What might have happened if antenna theory had taken another path, one that led to simplification instead of increasing mathematical sophistication? This column will explore one such “what if”. The example comes from the world of wire antennas; however, thanks to the Theory of Complementary Antennas, it also embraces small apertures. No doubt, such stories can be told about the world of large apertures as well.

Pierre Piel, applications engineer at Freescale Semiconductor, talks about some of the areas where microwave technology is being utilized in medical applications and what some of the performance requirements are for LDMOS devices.

An attractive alternative for providing a true broadband experience for the nomadic user, by adding user-financed femtocells to the network which benefit from improved radio conditions, is explored.

System-level analysis has moved from its former position at the end of the design process to the forefront where it can do the most good, at the least cost, with the least design disruption. Industry use of system-level analysis has lagged behind the level of “mainstream” high-frequency circuit design tool usage. It’s not surprising that many designers have created their own spreadsheets in Excel to perform these analyses. While many designers will no doubt continue to use spreadsheets for system-level analysis, their inherent limitations can prove costly.

GaN offers advantages due to its high efficiency, relatively high input and output impedances, and robustness; however, new designers may be wondering what surprises may crop up as they work with the new technology. The most common problems faced by designers moving from LDMOS to GaN are covered here, along with a discussion of similarities between the two technologies.

While user interfaces in microwave CAE software have remained relatively stable, important strides have been made in simulation technology. Today, more designs incorporate integrated chip, package, module and board systems which are more difficult to design, analyze, debug and deliver in high-volume than the typical design of 10 years ago.