First-Hand:A Right Brain Romantic's Memories of Satellites and Deep Space Probes


A Right Brain Romantic's Memories of Satellites and Deep Space Probes

50 year members.jpg

Submitted by George D. O’Clock, PhD, Life Member and 50 Year Member, IEEE

In one of the last “Lyle’s Laws” articles that appeared in the winter, 2012 issue of The Bent of Tau Beta Pi, Dr. Lyle Feisel writes about “The Limits of Logic.” In that article, he states, “ - - - Engineering is not just pure logic. Good engineering does certainly employ logic, but it also must, at times, involve feelings or emotions, intuition, a sense of beauty, esthetics – a whole host of non-logical parameters.” Then, he makes a very profound and important recommendation with respect to engineering effort; “Think, but also feel.

Dr. Feisel’s philosophy and outlook have had a positive impact on many of his students. At the South Dakota School of Mines and Technology, Dr. Feisel was my EE Master’s degree advisor and EE PhD advisor. Interacting with him over the years had an influence on what follows.

In the late 1960’s, I was working at TRW Systems Group as a microwave device and satellite communication system design engineer. One of my program assignments involved a satellite system that required a long and involved clearance procedure. I was fortunate to have a very talented technician – designer to work with (R.J. Dauphinee, who was known as “Dauph.”). On paper, Dauph worked for me. In reality; he was a teacher, advisor and good friend. Dauph also recognized that I was a card carrying right brain romantic. He was very intuitive and had the ability to appreciate and communicate with that part of one’s personality. To this day, I still live on some of the advice and insight that Dauph gave me.

Until our clearances came through, the hardware that Dauph and I developed had to be placed in a wall compartment with an 18 inch by 18 inch doorway access (much like what one does with a urine specimen). Some unseen entity on the other side of the wall would open their doorway access and take it from there. Then, once we were cleared, we were allowed to work on the other side of the wall. Dauph and I were then given the responsibility to design and fabricate a larger part of the communication system for a satellite receiver. Since I was recently hired and a relative “newbie,” Dauph and I were assigned to the satellite receiver downconverter development effort; which was of lesser importance than the strategically and extremely important task involving the satellite receiver front – end upconverter. The most experienced designers concentrated on the upconverter.

For the downconverter, my design choice involved a slim circular shaped pattern in a microwave stripline configuration. The most popular design choice at that time involved a thick, wide, square shaped, ugly looking thing. I preferred the circular shape because it was curved like a woman’s form, it was symmetrical, and it was pleasing to the eye. With symmetry this design choice had another feature that I had not anticipated. It worked backwards. It was not only a frequency downconverter, it also worked as a frequency upconverter. So I came up with an analysis involving a few differential equations and matrix manipulations to show that the pleasing-to-the-eye and symmetrical round shaped design choice was better than the ugly looking square thing.

In private, Dauph often (and very diplomatically) critiqued my design choices. He often had interesting suggestions. But Dauph never voiced any criticisms of the frequency downconverter design choice. It was an intuitive decision, and he liked it. It gave us both a good feeling.

During several design reviews, I brought up the fact that our frequency downconverter could be used as a frequency upconverter for testing while the highly experienced folks were trying to get the “real” upconverter to work. I received polite laughter from managers and other design engineers. They told me that the passive downconverter could never achieve the performance levels that the active upconverter would be able to achieve once some of the performance variability problems were brought under control. At that point, I was perceived by some project managers and fellow design engineers as being naïve. Others privately voiced the opinion that I was obviously not very bright.

As months went by, the frequency upconverter costs were becoming excessive and the customer was upset and complaining bitterly about the high costs and lack of progress. The costs to develop the upconverter (that still did not work) were 40 times higher than the cost of our nice looking and symmetrical passive downconverter design. One day, while a very displeased customer was observing another round of unsuccessful upconverter tests in the lab across from ours, my boss threw open the door and rushed into our lab. He was disheveled looking, tie askew, sweating; and his voice was an octave higher than usual. I looked at him and said, “ - - - trouble in Paradise?” My attempt at a bit of “edgy” humor fell flat. At that point, my boss was desperate, and was now willing to take our downconverter, turn it around, allow it to work backwards, and substitute it for a very non-functional and very expensive upconverter. I gave him the gold plated engineering model we were testing and showed him which ports to use for input and output. He then walked back into the upconverter lab and closed the door. Dauph watched all of this and was amused. He knew, even before I did, that the people behind that closed lab door were going to have an opportunity to learn some valuable lessons.

About 20 minutes later, everyone walked out of the upconverter lab smiling. My boss looked very relieved. The nice looking, symmetrical design that worked backwards performed far better than the original active upconverter ever did. They found that something relatively simple, nice looking and symmetrical had a lot more capability and reliability than something complicated, expensive, not very pretty, and temperamental.

We can come up with a purely technical explanation concerning why the original frequency upconverter was unsuccessful. The original active upconverter design engineers did not account for the performance limitations that an active device imposes for the very wide bandwidth requirements that were specified. Bode, Fano, Youla and others published a massive amount of work to show that sub – system gains, return loss and stability have limitations and impose significant active device parameter constraints when large percentage bandwidths are required. The technical critique can be revealing. However, I prefer to think about the solution of this problem as the result of intuition and insight producing something with beauty and simplicity; that had the flexibility and capability to outperform an unpredictable and complicated beast. The experience provided a good example of how technology often needs the influence of art, beauty, feelings, the elegance of simplicity, empathy and intuition in order to produce something that performs well and is desirable, safe, cost effective, user friendly and reliable. Were he alive today, Apple Computer’s Steve Jobs would probably agree with most of that statement, and Dr. Feisel’s philosophy and recommendations, because many of the words in the previous sentence have been associated with Steve Jobs’ Six Pillars of Design philosophy.

A few years later, while still working at TRW, I was given an assignment to develop the communication receiver front – end for the Pioneer 10 and 11 deep space probe system. I did not realize it then, but part of the reason that particular assignment was given to me was because of the successful design choices that were made with the passive frequency downconverter – upconverter.

The Pioneer technical supervisors were curious about what kind of receiver front – end amplifier choice I would make. The front – end amplifier was critical. If it malfunctioned, the Pioneer deep space probe mission would be highly compromised. I did not spend much time agonizing over design choices. Feelings and intuition ruled. True to form, rather than choosing the rather complex and unpleasant looking optimized amplifier designs that use stub matching (even the word “stub” violated my esthetic sensitivities), I preferred a more streamlined configuration using a microstrip quarter wave matching element design. I chose this approach because it looked good, it was uncomplicated, low cost, and it felt good. In design reviews, some engineers questioned my choice because it was not an optimal design approach. However, some of the managers reminded the design critics about the previous successes that Dauph and I had experienced. I knew that this particular Pioneer 10 and 11 front – end amplifier design was the best choice, and Dauph never questioned it.

The performance history of these two deep space probes provides verification that many correct design decisions were made. Pioneer 10 and 11 were designed for missions lasting less than two years. However, the design choices made by many of us were obviously “right on.” Pioneer 11 signals were received for more than 20 years, and Pioneer 10 signals were received for more than 30 years. That says a lot for some of the device and system designs that were inspired by an artistic sense, were uncomplicated and were pleasing to the eye.

I remember the thought and effort that Dauph and I, and so many others, put into the Pioneer 10 and 11 deep space missions. There are many pleasant memories about what we did and what we accomplished. In about two million years, with respect to relative velocity differences, it appears that Pioneer 10 will be passing a region where the orange giant star Aldebaran (the eye in the constellation Taurus) will be located. I often think about that. In two million years, a part of all of us who worked on Pioneer 10 will still be out there on a very long journey. It will be passing by a large star with an Arabic name that means “The Follower.”

Feelings, emotions, intuition, empathy, a sense of beauty, and esthetics - - - combined with the fundamentals and logic of science and engineering; they all played a significant part in a very successful and soul – satisfying effort.