Microwave Journal

Old Crows Roost Again in Washington

November 19, 2019

The 2019 and 56th annual AOC symposium and conference returned to the Walter E. Washington Convention Center, far enough from the White House and Congress to keep the attendees focused on electronic warfare (EW) and not impeachment. The theme of this year’s event was Building the EMS Enterprise, where EMS means the electromagnetic spectrum.

Walter E. Washington convention center

For those not active in the EW community, AOC is shorthand for the Association of Old Crows, which was founded in 1964 as an association for those involved and interested in EW. The crows moniker evolved from ravens, the name given to the allies’ countermeasures operators during World War II. AOC is now the preferred designation for the organization and conference, as it seeks to recruit young people into science and engineering and, eventually, EW. “Old crows” probably isn’t the best marketing slogan.

This year’s conference began with a welcome reception Sunday evening, 27 October, followed by three full days of presentations, round tables, program manager briefings, awards and an exhibition populated by some 120 organizations. With a balanced mix of attendees from the services, government agencies and industry, AOC is fertile ground for networking and understanding the challenges and priorities underlying the DoD’s EW budget.

Monday morning’s keynote address featured Alan Shaffer, the Deputy Under Secretary of Defense for Acquisition and Sustainment. Tuesday morning, James Faist, Director for Research and Engineering for Advanced Capabilities in DoD, and Tim Grayson, director of the Strategic Technology Office (STO) in DARPA, presented the keynotes.

Among the more tantalizing presentations: an update on high-energy electromagnetic weapons, such as lasers and high power microwave, and a case study of the Russian and Ukranian EW tactics in eastern Ukraine.

Back to the theme of this year’s conference, John Knowles, the editor of the Journal of Electronic Defense (JED), explained that developing an enterprise approach is a relatively new idea for using, managing and controlling the spectrum in a theater. It’s a shift toward integrating previously independent and isolated strategies adopted by each of the services.

Another theme from the conference: speed and agility, particularly to counter the growing military capabilities of China and Russia. As potential adversaries adopt a “Silicon Valley” development philosophy for weapons systems — fast and iterative development — the U.S. needs to reduce its own development cycle time. Strategies for doing so include creating open systems that can readily incorporate new generations of hardware and software and adopting commercial technologies, leveraging industry’s R&D investment that far outweighs what DoD can fund.

One government-industry initiative promoting agility through open systems is the Sensor Open Systems Architecture (SOSA) consortium. SOSA’s goal is to develop a suite of open standards covering system architectures, mechanical configurations and the hardware and software comprising these systems. SOSA’s initial focus will be on radar, EO/IR, EW, SIGINT and communications systems. The consortium’s vision is for a company’s differentiation (IP) to reside outside of the standards, i.e., within the subsystems or components that conform to the standards. SOSA’s current membership comprises eight sponsors, with seven principal and 59 associate members.

Exhibitor Highlights

Mike Hallman, Jaime Leger and I walked the exhibition floor and gathered the following highlights from many of the companies attending AOC:

AOC exhibition

American Microwave, a longtime supplier of DC to 40 GHz control components and subsystems for the EW community, was just acquired by Ironwave Technologies, a holding company investing in RF/microwave firms supporting EW, communications, telemetry and surveillance. American Microwave joins Mu-Del Electronics, which also manufactures RF/microwave components and subsystems for defense applications.

American Microwave

Analog Devices (ADI) has deftly combined the MMIC and module technology and defense program heritage it acquired from Hittite Microwave with it’s own data converter and broad silicon semiconductor capabilities to successfully apply its “bits to antenna” strategy to the defense market. At AOC, ADI was discussing both the individual components it offers and how it can integrate them into subsystems. ADI displayed several products to underscore its capability, including a five-channel EW receiver covering 2 to 18 GHz in a 3U VPX form factor, which is now released to production. The five channels can be configured to suit system requirements, such as four receive and one transmit. ADI also demonstrated a phased array with 16 transmit and 16 receive channels, with all the channels aligned in phase. The system uses the latest ADI converters — 12 GSPS DACs and 4 GSPS ADCs — and achieves 84 dB spur-free dynamic range. ADI is offering a demo board for prototyping, which can save programs critical development time.

API Technologies offers a diversified range of RF/microwave and microelectronics components and subsystems and has a long heritage serving defense and space programs. In September, Terrence Hahn was named CEO. In a recent interview, Hahn said his early focus as CEO will be “growth, growth and growth.” At AOC, API demonstrated a range of products and technologies for the defense, space and aerospace industries. In addition, Rob Sinno, from API’s nearby Weinschel office, demonstrated the company’s 4209 series programmable attenuators, with six versions combining attenuation ranges of 31.5 or 63 dB and frequency coverage from 100 MHz to 18, 30 or 43.5 GHz. The attenuators can be controlled via USB, PIO, I2C, SPI and UART.

Announced in conjunction with AOC, BAE Systems said it was awarded a $36.7 million contract from the U.S. Navy to develop a dual-band fiber-optic towed decoy (FOTD). The dual-band design will expand the capabilities of the existing AN/ALE-55 FOTD, also produced by BAE Systems, which protects the F/A-18E/F. The new version will interface with the aircraft’s onboard EW equipment, as well as operating independently to enhance survivability of the aircraft.

Another tenured aerospace and defense supplier, Cobham offers a diversified portfolio of products gathered through many acquisitions, which gives it an enviable position on many defense programs. For several years, Cobham has been investing its IR&D in developing a Ka-Band phased array, one that can be used in radar, missile seeker, UAS, EW or communications systems. The array architecture comprises a GaN T/R MMIC and SiGe vector modulator, both flip-chip mounted to the antenna board, which contains a patch array. The GaN power amplifier provides around 1 W output per element over temperature. A unit cell comprising four channels can be scaled to create much larger arrays, as required by the system. A 256 element array would measure only 3.8 in. x 2.8 in. x 1 in.

Cobham array

Empower RF is aiming to displace TWT amplifiers with a C-Band, 90 kW peak, pulsed power amplifier (PA). This high power is achieved by combining 28, 4 kW GaN on SiC building blocks. Each PA incorporates embedded computers for control, and the individual PA building blocks can be hot-swapped, i.e., replaced without shutting down the system. This modularity gives the design an inherent reliability advantage over TWTs. Empower RF is funded to build a prototype and plans to add the product to its catalog later this year. The same GaN PA board can be scaled to S-Band, achieving 5 kW per module.

Keysight demonstrated several use cases, showing how individual instruments can be linked and tailored for signals intelligence and EW systems. Keysight has introduced a threat simulator, including software and hardware, to create a realistic electromagnetic environment for validating EW systems. Testing in a lab is more efficient and much less expensive than flight tests, and lab testing is effective assessing subsystem and system performance before a flight test program. Keysight’s threat simulator combines the UXG Agile Vector Adapter with Simulation View software. The UXG provides fast frequency, phase, amplitude and time delay switching with real-time pulse descriptor word streaming; Simulation View enables real-time RF modeling and dynamic visualization.

Kumu Networks has developed interference cancellation technology that enables a radio to operate in full-duplex mode or separate radios to operate in close proximity, whether geographic or frequency. Combining analog RFICs with digital signal processing enhances the capability to dynamically cancel interference from the main signal and noise power from an adjacent signal, even with changing propagation conditions such as multipath. Kumu’s technology is equally beneficial for military and commercial systems.

Born through the merger of L3 Technologies and Harris at the end of June, L3Harris was presenting the new company’s combined capabilities and portfolio, addressing how L3Harris will serve the EW community. HalcyonLink was one of the systems featured. Developed by Harris, it enables soldiers to use their tactical radios while nearby systems are jamming enemy communications or IEDs. The HalcyonLink box connects between the antenna and the radio, samples the jamming signal and creates an out-of-phase copy that is added to the receive path to cancel the jamming signal. HalcyonLink can suppress interference by more than 80 dB, enabling soldiers to use the radio without turning off the jammer.

Lexatys began in 2004 by providing laser-machined planar filters on ceramic, quartz or soft substrates. Not requiring masks, laser fabrication is faster than conventional manufacturing — hours versus weeks — and can be used in an iterative tuning process to finalize a design. Lexatys has since expanded its capabilities, extending the initial service to designing and manufacturing custom components, multifunction assemblies and subsystems operating to 50 GHz. Lexatys’ designs include amplifiers, diplexers, switched filter banks, block down-converters and synthesizers.

Using its expertise in composites, Meggitt develops and manufactures radomes for military applications, including conformal designs for EW platforms. The company also provides testing services for antennas and radomes, offering its internal facilities to other companies and organizations. Meggitt has five far-field ranges with the capability to test from 220 MHz to 40 GHz using a linearly polarized, rotating source. The far-field ranges are supplemented with a compact range using dual, linear feed antennas for 2 to 18 GHz and banded feeds for 2 to 50 GHz.

Meggitt booth staff

I had the opportunity to talk with Bill Conley, the new chief technical officer of Mercury Systems. He previously served as the director for EW in the Office of the Secretary of Defense, as well as executive secretary for the Electronic Warfare Executive Committee. At AOC, he chaired a session on advanced technologies for spectrum operations, discussing how new technologies such as AI and computing can be combined with new operational concepts to disrupt warfighting. One of his interests is how DoD can best leverage commercial technology, since DoD’s ability to fund technologies such as semiconductors is dwarfed by industry investment. At Mercury Systems, Conley will be looking at DoD’s challenges from an industry perspective, helping Mercury develop its technology roadmap.

NEL Frequency Controls, a manufacturer of low phase noise oscillators, presented its family of crystals and crystal oscillators for RF/microwave applications. Under the name Sync N Scale, NEL has also developed timing solutions for synchronizing clocks across servers in data centers and edge computing. One interesting requirement for some edge networks is having UTC accuracy without accessing the IT network. Sync N Scale uses GPS time and frequency signals to sync the computer’s clock, which provides resistance from tampering.

National Instruments (NI) had a couple of demos running, one emulating a phased array radar using FlexRIO transceivers, the second a software-defined radio (SDR) for drone defense. The SDR uses the Ettus Research USRP N320 and USRP N321, which cover 3 MHz to 6 GHz with 250 MSPS sampling per channel. The SDRs sense and digitize the spectrum, and the system uses machine learning to classify the signals and identify which are drones.

This was the first year Pasternack had a booth at AOC, a reflection of the company’s growing line of products for defense and space. Among these, Pasternack has developed an extensive line of RF/microwave cable assemblies for high reliability applications. To support its commitment to same-day shipment, the cable assemblies are manufactured using qualified processes and lot traceability. All key parameters are tested, and test reports are provided with each shipment. Pasternack is also expanding its antenna line and has added 100 new models to its catalog.

Timed for AOC, Pentek released a recorder for signal intelligence, adding to its Talon family of recorders and playback systems. The rack-mount RTR 2654 scans from 800 MHz to 26.5 GHz, capturing 500 MHz of instantaneous bandwidth and storing the data on a solid-state drive, with a storage capacity of 245 TB. A built-in Pentek Jade transceiver does the data acquisition, using one of its dual 3.2 GSPS, 12-bit ADCs running at 2.8 GSPS. The data acquisition signal-to-noise ratio is 57.5 dB, with 72 dB spur-free dynamic range.

Planar Monolithics Industries (PMI) highlighted a 1 to 18 GHz channelized receiver with 20 separate outputs to feed digitizers. The PRX-20-1G18G-850M-SFF provides an internal reference to lock the down-converting local oscillators and has an output bandwidth of 900 MHz, with a maximum output frequency of 5 GHz. The input power range is from −55 to +5 dBm, achieving a spurious-free dynamic range of 60 dB. The receiver is powered with +12 and −5 V supplies.

Pole Zero, one of the companies within Microwave Products Group, has released a new generation of NANO-POLE® tunable bandpass filters covering the range from 225 to 3000 MHz. This generation offers higher power handling (23 to 30 dBm depending on bandwidth) and smaller size (20 mm x 12 mm x 7.6 mm). The tuning time is typically within 10 µs, and insertion loss is 4 dB for filters with a 3 dB bandwidth ≥7 percent. The filters are biased with +3.0 V and draw approximately 3.5 mA.

Pole Zero booth staff

Like BAE Systems, Raytheon announced a contract award to develop a dual-band towed decoy for the F/A-18E/F. This new version will extend the protection capabilities of the AN/ALE-50, also developed by Raytheon, which flies on the F/A-18E/F, the F-16 and B-1B. Raytheon received $33 million from the Navy for the development.

Rohde & Schwarz (R&S) offers a broad line of test equipment and integrated measurement solutions for defense and space applications, and many were displayed at AOC, including a van outfitted with gear for signals analysis. R&S demonstrated a system for generating EW test scenarios, which can create up to 256 emitters and interleave emitters of various types. Emitters can be constructed having I/Q modulated pulses, inter-pulse modulation such as PRI and RF stagger — even simulated antenna patterns and scanning. The emitters can be constructed internally or imported from lists of pulse descriptor words. Another demonstration in the booth created radar echoes pairing a R&S FSW signal and spectrum analyzer with an SMW vector signal generator. The system can simulate static path, pure Doppler, Rayleigh, Rice, constant phase or hybrid echoes, with ranges from 2.1 to 10,000 km. The echo generator can create up to four paths with six targets per path, yielding 24 echoes with arbitrary range-Doppler cells. The frequency coverage of the system extends to 40 GHz and a maximum instantaneous bandwidth of 160 MHz.

Rohde & Schwarz van

Signal Hound is adding capabilities to its SM200 spectrum analyzer and monitoring receiver. The original version, the model A, offered 40 MHz I/Q outputs, which was extended to 160 MHz instantaneous bandwidth in the model B. The B version also added a 2 s buffer and USB 3.0 interface to transfer I/Q data to a PC. The next generation — the model C, to be released next summer — will provide a continuous data stream via a 10 GbE SFP+ interface. It will retain the 160 MHz instantaneous bandwidth and 100 kHz to 20 GHz coverage of the B version. The continuous streaming makes the unit more useful for signal monitoring

Tabor Electronics exhibited its line of Proteus arbitrary waveform generators (AWG) and arbitrary waveform transceivers (AWT), available in PXIe, desktop and benchtop configurations. The 16-bit AWG configurations extend from 1.25 to 9 GSPS. The PXIe versions of the AWTs are available in dual- or four-channel, 16-bit, 1.25 or 2.5 GSPS models or a dual-channel, 16-bit, 9 GSPS configuration.

Teledyne Defense Electronics made several announcements at AOC, leading with a 6U VPX transceiver covering 6 to 18 GHz with 1 GHz instantaneous bandwidth. The air-cooled unit will tune to within 10 kHz in 5 µs, which Teledyne says is the fastest in the industry. The transceiver has 17 dB typical noise figure, −113 dBc/Hz phase noise at 1 MHz offset and 90 dB linear dynamic range with 1 MHz bandwidth. The second new product is a 4 kW pulsed, X-Band GaN power amplifier designed for rack mounting (4RU). Frequency coverage is 9 to 10 GHz, typical saturated output power is 66.1 dBm, with a pulse width from 1 to 100 µs and 10 percent maximum duty cycle. The modular power amplifier combines eight, fan cooled GaN modules, each with 550 W output power, which gives the overall amplifier graceful degradation should a unit fail. The fan units are hot swappable.

Joe Graycar demonstrating Teledyne's new 6–18 GHz transce.iver

Texas Instruments (TI) highlighted its latest generation ADCs and RF synthesizer and how they enhance the capabilities of EW and other defense systems. The ADC12DL3200 is a 12-bit, RF ADC with 6.4 GSPS sampling single-channel or 3.2 GSPS dual-channel. The full power input bandwidth is 8 GHz, which enables direct sampling into X-Band. The low voltage differential signaling (LVDS) interface is well suited for applications where low latency is a requirement, achieving latency below 10 ns. A newer, 12-bit ADC achieves 10.4 GSPS single-channel or 5.2 GSPS dual-channel. The ADC12DJ5200RF design uses a JESD204C interface with up to 16 serialized lanes yielding a 17.16 Gbps maximum line rate. TI’s LMX2594 synthesizer covers 10 MHz to 15 GHz, achieving −110 dBc/Hz phase noise at 100 kHz offset with a 15 GHz carrier. The internal phase-locked loop has a figure of merit of −236 dBc/Hz.

Viavi Solutions exhibited their vector signal analyzer (VSA) and vector signal generator (VSG), a combined unit in a 4U rack-mountable housing. The Vivavi Ranger features “deep memory,” enabling signals to be recorded for more than 2.5 hours using 200 MHz instantaneous bandwidth or as long as 10 days with 2 MHz bandwidth. The VSA will cover 100 kHz to 6 GHz or, optionally, to 30 GHz. The VSG will generate signals from 100 kHz to 6 GHz. The unit comes with Signal Workshop™, a software package that controls all instrument operation, with post-capture analysis capabilities.

You’ll find our gallery of photos from AOC here.