Microwave Journal

As a member of an application-support team, we regularly write and rewrite several application notes dealing with how to mount the RF transistors for maximum RF performance. Through history, application notes such as AN1040, AN1041, AN1617, AN1673, AN1674, AN1907, AN1918, AN1923, and the latest versions of AN1949, AN3263 and AN3789, all deal with recommendations for device mounting.

The old expression, “you get what you pay for,” usually holds true. Except in the case of a handy little design program called the MWI-2010 Microwave Impedance Calculator, available for free download from the Rogers Corporation website. Visitors to the DesignCon® 2011 exhibition (Santa Clara Convention Center, Santa Clara, CA, February 1-2, 2011) can learn more about this powerful transmission-line modeling tool by visiting Rogers at Booth 711.

I can’t remember at which airport I was when I read this USA Today headline: “The Year We Stopped Talking.” And without reading anything more, I knew the article had to be about social media, texting and the many wonderful wireless gadgets that have become necessary to our survival in the 21st century. We have certainly moved away from voice as the primary means of exchanging information and replaced it with text messaging. While I accept that we have become a world of ‘thumb’ and ‘touch screen’ typists, I can’t agree that we don’t need to communicate by voice as well, whether via skype, cell, or even the old fashion way...face to face.

Well, another IMS has come and gone, and once again we survived the chaos of getting ready and then pulled off a fantastic show. While wandering the show floor and perusing other exhibitors’ booths, I couldn't help but notice a clear divide between booth personnel who looked happy and excited and those who looked a bit disconnected, and yes, even bored. Then after I returned to the office I coincidentally viewed two interesting videos, one on YouTube and one on 60 Minutes –thank you Mom & Dad for making me watch this over the years- that gave me one possible answer.

AWR’s current ad, “Ideas Grow Faster in the Right Environment” graces the front of our 2010 AWR Magazine (6mb PDF) this month. There are many interpretations stemming from this visual (pun intended) that can be explored. But for now and for the purpose of this blog, the sprout portrays AWR’s corporate culture: innovation, spawning new ideas, the right environment for creativity, growth into new markets, seeds of change…

Yeah, what about Bunny? Early in February, I attended DesignCon 2010, and, aside from having a number of really great meetings with customers, partners, and media, I was curious if there would be a return of Bunny. As all of you who attended DesignCon 2009 will remember, Bunny was the talk of the show (for better or worse is a personal judgement call).

Dane Collins, our CEO, recently sent me a link to a thought-provoking blog by Umair Haque on the Harvard Business Review website. The headline boldly asks, "Is Your Business Useless?" Before I read the first word, I knew I'd likely smile as I read through it. Having spent nearly my entire career in high-frequency (HF) EDA, I was already willing to admit that this industry isn't overtly socially friendly. I mean, we are largely a group of engineers whose typical stereotype is introverted, so stepping out into the spotlight to draw attention to ourselves, and, on top of that, to make a point of being "socially useful".... this was going to be good.

Isn’t designing a microwave filter as simple as loading parameters into a computer-aided-engineering (CAE) program? In truth, many modern CAE software tools are quite good, and can provide accurate predictions of performance when fed sufficient input data. However, most do not account for all variables influencing a high frequency filter, including the effects of anisotropic printed-circuit-board (PCB) materials. When designing RF and microwave filters, it helps to choose your PCB material wisely.

Here in the Freescale Application Support Department, we get lots of calls from RF design engineers, who are in a desperate, crises mode. They have created a design using the best simulation tools possible and after having just built up their first prototype units, they are having some sort RF performance issues of varying degrees. Sometimes it is poor RF performance numbers not in line with the data sheet, sometime it is spurious oscillations, or shifting RF performance numbers with temperature or maybe even, in extreme cases, total device failures.

Most people working in the high power RF design arena think that they know a fair amount about high power RF products and the devices that comprise that market space. I am here to tell you that there are three relatively interesting and unknown facts about the high power RF product market that the consumers generally do not comprehend.