This series looks at the past five decades of our industry as described in this magazine. In this third installment of our six-part series, we focus on the 1970s, the decade of Watergate, a gas crisis, Americans held hostage in Iran... ah, yes, good times. At least we had disco to help us dance away our malaise.

Despite some low points between 1970 and 1979, the microwave industry was robust with innovations on multiple fronts and healthy government and private funding. Microwave solid-state devices and microwave integrated circuits (MIC) continued to develop and allow new systems such as the next-generation of airborne weather avoidance radar, phased arrays, radio-telescopes, more satellite communications and microwave links for telecommunications.


Numerous contributors openly contemplated data communication at GHz rates and fiber optics became reality. In 1970, analysts Frost and Sullivan predicted that the data-communications market “could be worth $2 billion dollars by 1975 and that data traffic could capture 50% of the telephone network by 1979.” Here’s a sample of what appeared on the pages of Microwave Journal.

January 1970

This issue was dedicated to ferrites and filters. Articles included “High Performance YIG Filters,” “Recent Trends and Advances in Filters and Couplers” and “New and Unique Ferrite Devices.” Associate editor Seymour B. Cohn wrote an opinion piece entitled “Computers Have Limitations, Too” that celebrated the computer’s role in allowing laboratories to do “sophisticated design work,” but also warned “that computers cannot think” and that the engineer “should decide beforehand whether his purpose is best served a direct approach or by digital optimization.” While engineers today still get into trouble for optimizing every possible parameter or accepting simulation results without fully understanding if the problem is properly defined, the author would no doubt be impressed by how close today’s software comes to actual thinking, greatly simplifying many design tasks.

Publisher William Bazzy discussed “the recent vote in the US Senate on the anti-ballistic missile program Safeguard.” With an approved budget, Bazzy pointed out that, “the new need is to develop and produce the microwave hardware and special test equipment that is part of the Perimeter Acquisition Radars (PAR) and Missile Site Radars (MSR) and the associated Spartan and Sprint Missiles.” Bazzy went on to note that while phased-array radars had been investigated since the mid-1950s and reported in the Journal since 1959, the R&D programs in play during the 1970s would bring these systems to the point of technological feasibility. Bazzy concluded that, “In view of the importance of the entire anti-ballistic program, we will continue to report on those aspects affecting the microwave community, such as the impact phased-array radars will have on the components industry, the solid-state group, test equipment requirements, etc.”

December 1971

Staff changes are reflected in the masthead with William Bazzy now serving as president-publisher, Ted Saad as vice president and Charles E. White assuming the lead editor position. Assistant editor R.C. Hansen wrote an editorial on “Future Antenna Trends at Allerton,” in which he discussed the outcome of the USAF annual conference on antenna R&D, held for DoD antenna contractors. Conference attendees agreed that due to a tight money situation, the needs of the system would be the driving force behind antenna R&D. They also agreed on the continuing importance of computers in antenna design and analysis, almost 20 years before the first commercial electromagnetic software is available. Hansen wrote, “In the design area, computers will be even more vigorously used. Most designs will still use results of appropriate analyses, but the scope of these analyses will increase, especially in methodology wherein the computer simulates the current carrying surface. More powerful moment-type methods are to be expected. Design utilizing optimization codes will be limited in use, mostly due to cost but also because complicated problems often have subsidiary maxima.” (Incidentally, this conference, the 2008 Antenna Applications workshop, is still held today, taking place this month from September 16 to 18 at Allerton Park in Monticello, IL).

On computer optimization of antenna design, the author concluded that “optimization using moment methods without heavy use of engineering judgment to greatly reduce the number of cases is indeed a bold venture unless one’s computer time is free.” Today, Microwave Journal receives many antenna papers utilizing commercial software to generate and optimize antenna designs. We applaud today’s electromagnetic simulation software and optimization capabilities, and marvel at how they have allowed our industry to design components with functionality unimaginable just a few years ago. However, it is our long held belief that a solid understanding of engineering principles is critical to successful design and contributors need to share this knowledge with our readers. For this reason, papers that fail to discuss the engineering principles governing the antenna behavior and dictate design considerations are typically rejected.

An application note from this issue, “Detection Range Measurements on a Simplified Doppler Radar” by General Electric, described the use of the transferred electron effect in Gallium Arsenide bulk material to produce a useful diode oscillator microwave (X- and K-band operations) power outputs at low power supply voltages and with a low noise spectrum around the carrier. Potential applications included intrusion alarms, radar speed detectors and the system shown in Figure 1 depicting what appears to be an early collision avoidance system for cars.

Figure 1 – Gallium Arsenide bulk material produces a useful microwave diode oscillator for use in an early collision avoidance system for cars.

January 1972

The cover of this issue features a collage depicting various aircraft making an approach for landing or take off, highlighting the theme of Microwave Landing Systems. Three technical features include a “Step-Scan to the Radio Technical Commission for Aeronautics Landing System,” a “Microwave Doppler Scanning Landing Guidance System” and a “Microwave Landing System Using Continuously Scanning Beams.” The editorial feature for the month by Robert Shank brought into sharp focus the safety issues plaguing air travel in the early 1970s.

Today, we take for granted a flight crew’s ability to land planes despite poor weather conditions such as fog, rain or ragged cloud ceilings. But the crash of Flight 932 that killed 75 crew and passengers (including the Marshall University football players, coaches and fans travelling with the team) on November 1970 brought the hazards of flying in poor weather into the nation’s psyche (figure 2). The excerpt from Shank’s article talks about our industry’s efforts to improve landing system reliability.

Shank writes, “The year 1971 was not kind to the technical community. Its judgment and its intentions were questioned by such events as the scrapping of the SST or cutting back the NASA Space Program; and its capabilities were blamed for the pollution mess and abusing the ecology. After all, shouldn’t the scientists and engineers have foreseen this when they were putting America on wheels or building our super-productive industrial machine and super consuming economy!... To prove that some engineers and scientists do look ahead, 1971 was also the year in which over 30 years of effort by a diligent and, sometimes, stubborn group was rewarded by seeing a major project get underway to develop their concepts. We refer to those who have been trying to introduce World War II technology into the Aviation Approach and Landing problem, which remains aviation’s leading cause of accidents and fatalities.” Thirty-seven years after this was written, we all appreciate safer airline travel thanks to these engineers. In 1971, multiple advertisements from Raytheon featured their pulse modulator packages being utilized in “most major weather programs” touting this success of the microwave industry.

Figure 2 – The Crash of flight 923 and the Marshall University football team in poor weather highlighted the need to develop weather avoidance radar.

March 1973:

Another milestone this year as the publisher’s torch gets passed from Bill Bazzy to Howard Ellowitz, a 20 year veteran of M/A-Com and Alpha Industries. Howard’s first editorial contribution was a report on the IEEE International Solid State Circuits Conference in Philadelphia (attendance 1100+). This month also included guest editorial from Dr. Joseph Saloom (Varian Associates) who wrote a commentary on Microwave Tubes in the marketplace and Bill Bazzy writing his last editorial as publisher. In it, he discussed the decline of the tube market, blaming the decline on an electronic recession accompanied by a serious level of attrition. Bazzy mentioned that despite a weak recession in 1970 and 1971 compared to 1963 and 1964, too few companies had invested sufficient money in new product development which further hurt US companies competing in the communications markets just as radio relays were being employed as the backbone of expanding analog and digital networks.

George Heilmeier from the Office of Defense R&D, wrote about Microwave Tubes and the Defense Electronic business. Dr. Heilmeier saw the problem as a matter of economics, in that the tube market was on a trajectory to price itself out of the defense market. He noted the cost of a tank was doubling every ten years while that of an airplane was quadrupling, mainly due to the cost of avionics. Ken Evans of Microwave Associates also provided an overview of the Microwave Tube market, looking at the tube market in military - Surface and Airborne Radar, ECM, and commercial - industrial heating, cooking, communications. Ken concluded that 1972 saw a resurgence of activity for the US microwave-tube industry, but clearly everyone writing on the tube market in 1973 felt jittery about the future.

The subject would come up repeatedly as later months focused on EW (May articles on Dual-mode Tubes by Yarrington and Maynard, “TWT’s for Airborne Radar” by Dr. Mendel and “Why tubes are here to stay” by Feehan); Radar (August article by Smith and Wilczek on “CFA Tube for Coherent Radar”); and ECM (September with articles by Dr. Moats on “TWTAs for ECM” and Dr. Smith on “Tube transmitter interface in Airborne Radar”).

Why the intense interest? In Southeast Asia and Vietnam, the effectiveness of the enemy’s EW at downing aircraft had shown the military that ECM systems were critical to protecting fighter planes and their pilots (as pointed out in Norm Pond’s September guest editorial - “EW Microwave Tubes: More for Less?”). At the time, tubes provided the microwave power for these systems, which in turn were responsible for the market recovery whose earlier decline had been felt strongly by everyone in the tube business. Recognizing the importance of this market to their bottom line, many authors wrote about tube technology and the needs of EW and ECM systems.

The solid-state folks were eager to write about their technology as 1973 also produced many papers referencing other microwave power producing devices such as IMPATT diodes and X-band bipolar transistors. While the power levels and reliability of these devices would not yet rival the tubes, change was in the air. As an indication of things to come, the final issue of the year featured an article from Microwave Power Devices of a Class A linear Power Amplifier with 38.5 dBm saturated output power based on cascaded transistor stages.

February 1978

Jumping five years ahead, Microwave Journal was celebrating its 20th year in publishing. The Publisher’s Corner, an editorial feature started by Howard Ellowitz was now the familiar “Sum Up” feature that would appear in the magazine through the rest of the 70’s, 1980’s and into the early 1990’s. Conference coverage included the ISSCC, Synthetic Aperture radar Conf., EMI/EMC Seminar, mw Mobile Communication Symposium, Sub-millimeter wave Conference, Satcom Systems and the Pulse power Modulator Symposium. Associate Editor Colin Bowness kicked-off a 20 year perspective series with a special report, “Fast journey backward and a long look forward by our early writers”. Colin examined the ferrite market, using content from his 1958 article as a starting point.

To coincide with the annual ISCC, the majority of articles in February were dedicated to solid state technology. In his guest editorial “An Impending Crisis in Materials”, Frank Brand of Microwave Associates wrote “the devices made with this material have been so promising that demand will undoubtedly be high, creating the potential for a shortage of actual gallium arsenide material.” Dr. Brand cited examples of GaAs FET performances such as 5 watts at X-band and noise figures as low as 2 dB at 10 GHz as “nothing short of mind boggling”. With potential opportunity for new GaAs devices (excluding integrated circuits) to be in the $20 - $25m range, the lack of “a single, non-captive, viable source for high quality GaAs material optimized for microwave use” posed an eminent threat. At the time most device manufacturers were relying heavily on suppliers whose primary interests were geared toward larger markets namely – light emitting and laser diodes. In the next few years, this situation would turn around as companies invested heavily in building their own captive fabs.

Other theme-related articles included a business report on GaAs FETs - Technology and Business review by the Microwave Journal staff, a cover story from Raytheon on an “X-band Planar Combiner Module using GaAs FETs”, “GaAs FET Developments – Low Noise and High Power” from Jim Dilorenzo writing from Bell Laboratory, “Small Gain Amplifiers for Front End Designs” from Hundley, Estabrook and Crescenzi of Watkins-Johnson and R.V Garver of Harry Diamond Labs writing about “PIN Diodes Switches – Speed vs. Power.”

Tubes would get the spotlight again in the July issue but not before the April cover story from Aercom Industries titled “18 – 26 GHz TWTA Replacement” featured pictures of a matched 40 watt 800 MHz transistor going toe-to-toe with a TWTA. By July, microwave tube articles with titles such as “The Microwave tube Industry – Overcapacity or Underachievement”, “A Review of the Microwave Tube Climate”, and “New Horizons for Microwave Tubes” would paint a gloomy (yet hopeful) future. In particular, “The review of the tube climate” by Nathan Butler (a follow-up to his very dire 1975 article) wrote that a shrinking number of manufacturers - “will need to design to cost, produce low cost tubes for small quantities and shift to millimeter waves in order to survive”. While not extremely optimistic about the future of this technology, Butler stated that the only hope for its survival was more innovation.

February 1979

This issue dedicated to sources and combiners included articles on phase locked swept oscillators by E-Systems, “Oscillator Design by Device Line Measurement” by Raytheon, Sub-millimeter wave BWOs by Thomson CSF, “Impedance Matched In-phase Power Dividers” by Sage Laboratories and “Phase-staggered Combining” by Bendix Corp. A special report by Dr. J.H. Bryant of Omni Spectra entitled, “The Manpower Crunch in a Boom” revealed the favorable economic state of the industry while showing concern for a shortage of “qualified career oriented microwave engineers”. Dr. Bryant presented the industry as a vital one, growing at a rate of over 8% per year with some solid state products growing at an annual aggregate rate of 25% or greater and achieving greater penetration into more and more segments of society. With opportunities in global (and interplanetary) communications, air traffic control, police and boat radars, security, vegetation and crop surveying from satellites, cancer therapy, the need for more engineers with all levels of training was critical to continued growth.

This theme would recur in a November editorial by Paul Backus entitled, “The Microwave Engineer”. Dr. Bryant felt the immediate solution to the manpower shortage was to improve individual efficiency and to work more closely with universities. The author felt that industry-university interaction up to this point had been vastly insufficient. The author implores the private sector to take on some of the financial support for university research and student training, which till that point had come largely from government.

May 1979

In his article, “What’s in a Good Paper?” Consulting Editor, Joseph White tells would-be authors what our editors take into consideration when reviewing papers. “The Microwave Journal is in many ways like the various publications of the IEEE, in that it strives to place new and interesting theories, methods, measurements, etc., that are germane to the microwave engineering before its readers in a competent, objective and accurate fashion. In fact, our confidential review sheet was modeled after that used for the MTT Transactions’ reviews.”

Dr. White then remarked on the fundamental differences between the Microwave Journal and IEEE publications. “The first difference, as I see it, is in the readability of the magazine itself, The (IEEE) publications are intended as concise, terse technical ledgers of accomplishment, theories, analyses, and forefront results. It has been said the IEEE’s strong suit is its archival function. These IEEE papers and letters most likely will not be read upon receipt. Rather, he (the engineer) will file them in his library, referring to them if and when he perceives a need to be brought up to date on a special method or process.”

The editor considered the Microwave Journal distribution of 44,000 people compared to the IEEE Transactions 5000 recipients and made the case for how this required a different editorial direction. “It should be possible for a practicing engineer to read the Microwave Journal issue in about the same period of time he spends with, say, Time or Newsweek magazines. This is generally one hour for the more serious reader.” Additionally he notes that MWJ articles must be written for the majority of readers, who “are technically oriented but not as conversant as those practicing at the forefront of a particular specialty.” To Dr. White, good papers conveyed the message verbally as well as with equations, photographs, graphs and tables. In general, he considered derivations, which were more than the reader could follow to be more unnecessary (appearing in the appendices, if at all).

Summary

The decade started with congressional approval for an anti-ballistic missile program and our technology on a trajectory to make phase array radar a reality. It concluded with the installation of the Raytheon developed Pave Paws (phased-array warning system) sea-launched and intercontinental ballistic missile detection and tracking system, which was completed at Cape Cod Air Force station in 1978 and activated as the 6th Missile Warning Squadron on October 1, 1979. Microwave Integrated Circuits and solid-state technology made great advances while the TWT industry experienced several ups and downs. By the end of the decade, the industry had gone from recession to solid growth and diversification. The community was talking about the pending needs of data-communication and the information age. Subsequently, microwave radio links and fiber optics were poised to take off and the need for more qualified microwave engineers was growing painfully apparent.