New Radiation-hardened electronics enable military small satellites in Low Earth Orbit (LEO) to deep space missions

Rajesh Uppal February 13, 2022 Electronics & EW, Industry, Manufacturing, Space Comments Off on New Radiation-hardened electronics enable military small satellites in Low Earth Orbit (LEO) to deep space missions 1,159 Views

There has been rapid growth in New Space applications like small satellites (small sats) and Low Earth Orbit (LEO) mega constellations or satellite swarms. The increased U.S. investment in military space is driving growth in classified and unclassified applications.

The Satellite has a large number of electronic systems and subsystems which are critical to the functioning and its mission. The spacecraft is divided into two sections: the platform or bus and the payload. The platform consists of the five basic subsystems that support the payload: the structural subsystem, the telemetry subsystem, tracking and command subsystems, the electric power and distribution subsystem, the thermal control subsystem, and the attitude and velocity control subsystem. The structural subsystem is the mechanical structure and provides stiffness to withstand stress and vibration. It also provides shielding from radiation for electronic devices.

Space has become another domain of warfare and is becoming heavily militarized and weaponized. Space control and space access is driving growth in radiation-hardened (rad-hard) components.

Radiation Hazards

One of biggest threat to the deployed aerospace and defense electronics systems is radiation. The space radiation environment can have damaging effects on spacecraft electronics. Long term exposure of astronauts to radiation is equally challenging. Outside the protective cover of the Earth’s atmosphere, the solar system is filled with radiation.

There are large variations in the levels of and types of radiation a spacecraft may encounter. The radiation exposure to devices and signal paths does depend upon the intended orbit, potential shielding from the physical build decisions, and choice in radiation tolerant device materials.

Missions flying at low Earth orbits, highly elliptical orbits, geostationary orbits, and interplanetary missions have vastly different environments. In addition, those environments are changing. Radiation sources are affected by the activity of the Sun. The solar cycle is divided into two activity phases: the solar minimum and the solar maximum.

“We are really starting to see four quantums in the satellite space marketplace,” explains Anthony Jordan, director of business development at Cobham Advanced Electronic Solutions Inc. (CAES) in Colorado Springs, Colo. These four quantums consist of small cubesats with mission durations of only 12 to 18 months; business satellites with life spans of two or three years of mission life; so-called “constellation space” with each satellite expected to last in orbit for five to seven years; and finally the long-duration satellites that will operate in geosynchronous orbits for decades.

Satellite failures due to space radiation or other environmental conditions are tolerable for tiers 1 and 2 because the relatively low costs of these spacecraft enable periodic replacement. On-orbit failures become more problematic, however, for tiers 3 and 4. The first quantum primarily is for proof-of-concept research projects and can accept non-rad-hard components. The second quantum must have limited radiation hardening for short durations in low- or medium-Earth orbits. The third quantum must have some serious radiation hardening for multi-year missions, and the fourth quantum must have the most extensive levels of radiation hardening for decades of operation in harsh geosynchronous and polar orbits.

Jordan points out that many of the high-profile commercial satellite constellation projects are in the second and third tiers — particularly tier 3, which contains the Blackjack project of the U.S. Defense Advanced Research Projects Agency (DARPA) in Arlington, Va.; the Lightspeed data communications satellite constellation of Telesat in Ottawa; the Kuiper satellite constellation for global broadband communications from Amazon in Seattle; the Starlink constellation for broadband communications from SpaceX in Hawthorne, Calif.; and the OneWeb broadband communications satellite constellation from a joint venture of Airbus in Leiden, the Netherlands, and OneWeb in London.

This force can occur naturally in space and at high altitudes on Earth, or can come in massive doses from the detonation of nuclear weapons. Deep-space and long-duration missions, where both crew members and spacecraft no longer benefit from the protection of Earth’s magnetic fields, are considered high risk for adverse radiation impacts. Aircraft flying at altitude, at about 30,000 feet and above, also are starting to experience radiation-induced effects. “There are 500 times more neutrons at 30,000 feet than there are on the ground,” points out Aitech’s Romaniuk.

Radiation Impacts

Ensuring the reliable operation of microcircuits and software in outer space is an important scientific and economic objective. For, weather, communications and surveillance satellites to be cost-effective, they need to be operational for at least 10 to 15 years. Onboard electronic equipment failures are a common reason for early satellite failure.

Environments with high levels of ionizing radiation create special design challenges. A single charged particle can knock thousands of electrons loose, causing electronic noise and signal spikes. In the case of digital circuits, this can cause results which are inaccurate or unintelligible. This is a particularly serious problem in the design of satellites, spacecraft, military aircraft, nuclear power stations, and nuclear weapons. In order to ensure the proper operation of such systems, manufacturers of integrated circuits and sensors intended for the military or aerospace markets employ various methods of radiation hardening.

For stable and effective control of the sensor system, analog sensor signals such as temperature, pressure, and electromagnetic fields should be accurately measured and converted to digital bits. However, radiation environments, such as space, flight, nuclear power plants, and nuclear fusion reactors, as well as high-reliability applications, such as automotive semiconductor systems, suffer from radiation effects that degrade the performance of the sensor readout system including analog-to-digital converters (ADCs) and cause system malfunctions.

The computers in space must meet the radiation-hardness requirements of the severest space environment. However, the biggest market driver for radiation-hardened electronics is low-Earth-orbit space applications in communications and Earth observation, where missions might last only for a few years — or even just months — and where threats from space radiation are relatively low.

Radiation Mitigation technologies

There are various measures used to protect electronic circuits from radiation, One is the shielding of electronics which is not only expensive, but it also can be heavy enough to adversely influence launch costs. There are other ways of dealing with space radiation, ranging from redundant subsystems, selective shielding, and upscreening commercial off-the-shelf (COTS) electronics for enhanced reliability.

Radiation hardening

Radiation hardening is the process of making electronic components and circuits resistant to damage or malfunction caused by high levels of ionizing radiation (particle radiation and high-energy electromagnetic radiation), especially for environments in outer space and high-altitude flight, around nuclear reactors and particle accelerators, or during nuclear accidents or nuclear warfare. Radiation-hardened products are typically tested to one or more resultant effects tests, including total ionizing dose (TID), enhanced low dose rate effects (ELDRS), neutron and proton displacement damage, and single event effects.

There are several ways that electronic parts designers can radiation-harden their devices. One of the most common is to harden for total-ionizing-dose radiation – or the amount of radiation the device is expected to withstand for its entire life before problems occur. A typical requirement is for 100 kilorads of total-dose radiation hardness.

“As technology nodes decrease in size – from 90 nanometers to 14 nanometers – total ionizing dose performance naturally improves,” says Michelle Mundie, business area director of standard products at rad-hard specialist Cobham Semiconductor Solutions in Colorado Springs, Colo. However, because the steady shrinking of chip geometries also makes these devices even more vulnerable to other kinds of radiation effects, namely single-event upset (SEU) and single-event latchup (SEL). “Single-vent effects like latchup are becoming more of a problem, so we have to design for those effects,” Mundie says. “Devices today are more sensitive to radiation at the gate and transistor level.”

Normal semiconductor devices such as those in a typical computer would have sufficient soft errors at relatively low levels of radiation to render the computer unusable though not necessarily cause permanent damage. However, it is possible to make semiconductor devices that are very resilient to radiation – at least for a period of time. This involves different processing and careful design and, as a result, they are not cheap to make. Typically they will use a silicon-on-insulator process and complete computers can be made (and are made for military applications) that can withstand around 1 megarad, which would be lethal to a human.

Plastic packaging

Several experiments aboard the International Space Station are testing whether the space agency can move beyond traditional rad-hard components. NASA has long specified traditional and expensive radiation hardening of electronic components either by adding redundant circuits or using insulating substrates on semiconductor wafers. That brute force approach is expensive. HPE engineers came up with what they say is a cheaper approach for hardening electronics: “…simply slowing down a system in adverse conditions can avoid glitches and keep the computer running,” according to an HPE blog post.

Radiation hazards associated with a trip to Mars — at least 35 million miles at its closest approach to Earth — would likely be far greater than those in Earth’s orbit. Nevertheless, HPE engineers note that current commercial electronic components far exceed current radiation hardening requirements for the space station. Meanwhile, key components for future space computing platforms are expected to be available in the next few years. For example, the space agency expects its next general-purpose processor, a variant of the ARM Cortex-A53, to be cleared for launch in 2020.

The future standard will be MIL-PRF-38535 Qualified Manufacturing List (QML) Class P, and will be administered by the U.S. Defense Logistics Agency (DLA) in Columbus, Ohio. MIL-PRF-38535 is a U.S. military performance specification that establishes the general performance and verification requirements of single-die integrated circuits. It defines quality assurance and reliability requirements for integrated circuits used in military applications and other high-reliability microcircuit applications.

MIL-PRF-38535 space-qualified parts today typically are QML class V, for space-grade parts. These typically are high-performance and high-cost ceramic parts that are difficult to obtain. The future QML class P qualification should make a wide variety of space-grade parts available that are lower cost and higher performance.

Apogee Semiconductor in Plano, Texas, specializes in radiation-hardened plastic-encapsulated parts for space applications. “We are space plastics from the ground-up; we don’t have any hermetic ceramic parts in our portfolio,” says Apogee CEO Anton Quiroz. “There are too many performance tradeoffs — in a bad way — with hermetic.” “In ceramic we see limitations to speed and transfers per second, in a memory device or wired interface. You can’t push 50 gigabits per second through a ceramic package; you really need an organic package like plastic.”

Radiation hard/tolerant design

For stable and effective sensor systems, it is essential to improve radiation tolerance of the core circuit blocks, such as ADCs, by utilizing radiation-hardening by design (RHBD) in addition to shielding and CMOS process techniques.

For environments with high levels of radiation special technologies made to be immune to radiation must often be used (e.g. DMILL). Modern sub-micron CMOS technologies can often also be used in high radiation environments if special precautions are made in their design (e.g. enclosed transistors with guard rings).

Basically all CMOS technologies will be sensitive to single event upsets in their memory elements unless special schemes have been used. The general principles used to be insensitive to single event upsets is to use triple redundant logic and memories with error correcting codes (e.g. Hamming coding). Circuits with large memories and S-RAM based FPGAs should only be used in radiation environments after a careful analysis of single event upset problems. The problem of single event burnout in power MOSFETs can in many cases be resolved by using a de-rating factor of ~2 of the main voltage and current limitations of the power transistor (implies redesign of power supply).

BAE Systems Delivers First Radiation-Hardened RAD5545® Radios

BAE Systems has delivered its first shipment of next-generation radiation-hardened software defined radios (SDR) enabled by its RAD5545 computer to Lockheed Martin Space. The radios provide spacecraft with the performance, availability, reliability and on-board signals processing capacity needed to support future space missions — from planetary exploration to communications, national security, surveillance, and weather missions.

“Our RAD5545 software defined radios are ideal for any mission requiring reconfigurable radio processing,” said Ricardo Gonzalez, director of Space Systems at BAE Systems. “The radios can be easily modified to address various reconfigurable processing solutions.” BAE Systems’ software defined radio is anchored by the RAD5545 single board computer (SBC), providing the most advanced radiation-hardened quad core general purpose processing solution available today to address future threats on a variety of missions. The system leverages modular and standard building blocks including a SpaceVPX chassis and backplane electrical connectors, Serial RapidIO ® and Spacewire interfaces, and a fully supported expansion port for a custom interface card.

Adhering to industry standards, this flexible and adaptable architecture supports reconfiguration for other missions by simply swapping out SpaceVPX modules, a highly desirable feature in today’s space hardware. BAE Systems’ next-generation software defined radios, centered around the RAD5545 computer, represent a significant advance in high reliability reconfigurable electronics systems. Increased processing power, and a radiation-hardened design combine for a product line that can enable increased mission flexibility.

The RAD5545 SBC delivers exponential improvements in size, speed, and power efficiency over its predecessor single board computers. BAE Systems also offers a suite of radiation-hardened Serial RapidIO network products that complement the RAD5545 SBC and allow the user to efficiently manage and route data through a system. Products include the RADNET ® 1848-PS, an 18-Port RapidIO Packet Switch, the RADNET 1616-XP Crosspoint, a protocol agnostic SerDes signal circuit switch and replicator, and the RADNET SRIO-EP, a Serial RapidIO endpoint. The RAD5545 SDR was developed at BAE Systems’ sites in Merrimack, NH, and Manassas, VA, and is produced in Manassas.

STMicroelectronics Boosts Power Efficiency in Space Applications with New Radiation-Hardened Devices

STMicroelectronics has extended its portfolio of radiation-hardened power devices qualified for space applications by introducing new ESCC (European Space Components Coordination) qualified 200V and 400V power rectifiers and SEB -immune Schottky rectifiers at 45V and 150V. The rad-hard Schottky diodes include 45V and 150V devices, SEB immune up to 61MeV/cm2/mg linear energy transfer (LET). These are the industry’s first SEB-rated Schottky devices and are suited to use in many converter topologies. The 150V and 45V devices are ready for direct connection to 100V and 28V satellite power buses. The forward voltage (VF) of the 150V devices is 0.78V (max) at 40A/125°C. The maximum VF for the 45V devices is 0.61V.

In total ST is launching five ESCC-qualified dual common-cathode Schottky parts including the STPS40A45C that contains a 45V/2x20A diode in a TO-254AA through-hole package. The STPS80A45C with a 45V/2x40A diode, STPS60A150C 150V/2x30A, and STPS80A150C 150V/2x40A are packaged as SMD.5 hermetic surface-mount devices. The STPS40A150C 150V/2x20A is offered in TO254AA. The rectifier diodes are the STTH40200C 200V/2x20A dual diode in TO-254AA, and the STTH60200C dual 200V/2x30A and STTH60400 single 400V/60A diode in hermetic SMD1.

Radiation-Hardened Electronics Market

The market for radiation-hardened electronics was valued at USD 1.4 billion in 2020 and is estimated to reach USD 1.7 billion by 2026, registering a CAGR of 3.5% during the forecast period (2020–2026).

The growing intelligence, surveillance, and reconnaissance (ISR) operations globally, the increase in number of space missions, and growing demand for rad-hard electronics in the commercial satellite industry are factors driving the growth of the rad-hard electronics market. The radiation-hardened electronics market has gained huge importance in the past few years. This is due to the rising demand for commercial COTS applications of rad-hard components. Several agencies and research organizations and industry players are engaged in developing software-defined rad-hard components.

The COVID-19 crisis has led to global health and economic pandemic. This has resulted in a number of businesses shutting down their manufacturing plants and halting most of their operations. During this crisis, the main objective of companies is to sustain their businesses by finding safe ways to continue their manufacturing operations or explore other sustainable ways to get their revenue streams flowing. The demand for radiation-hardened electronics was increasing steadily in the pre-COVID-19 scenario. With tensions in China-US trade, the immediate impact of COVID-19 can be easily observed on the imports of radiation-hardened electronics in the US.

Segments

The manufacturing technique included rad-hard by design (RHBD), rad-hard by process (RHBP), and rad-hard by software (RHBS). the component type was classified into microprocessors and controllers, sensors, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), memory, power sources, discrete semiconductors, analog and mixed signals, others (optoelectronics, rectifiers, and fets). The market is further segmented into five end-use, namely space, military, nuclear power plants, aerospace, other (healthcare and mining).

The power management has been a major segment in the radiation-hardened electronics market. The growth of the power management segment is primarily attributed to the increasing need for MOSFETs and diodes for high-end applications in the space and defense industries. The power management components, such as power switches and metal-oxide-semiconductor field-effect transistor (MOSFETs), accounted for a major share of ~40% of the global radiation-hardened electronics market in 2019. Power MOSFETs are used in high-reliability requirements and designed for the outer space requirements. These have excellent durability against high-energy-charged particles and ionizing radiation. Due to the ongoing COVID-19 pandemic, the growth of the power management segment is slightly impacted but is expected to grow at the highest rate during the forecast period among the other components.

The radiation hardening by design (RHBD) segment is expected to grow at the highest rate in the radiation-hardened electronics market attributed to the low cost per chip, high volume of production, and ease of modification. The RHBD memories, microcontrollers, and ASICs are mostly used in the defense and space industries as well as nuclear power plants. The market for RHBD designs is accentuated during COVID-19 because RHBD allows easy modifications by various government programs depending on the intended applications. Though radiation hardening by process (RHBP) is an effective approach for the manufacturing of radiation-hardened electronics systems, its adoption rate among the microelectronics manufacturers is less mainly because of the low profits, process uncertainties, and the high cost of manufacturing.

The US and Europe are key importers of semiconductor components. The high import tariffs on radiation-hardened electronic components in these geographies, together with disruptions in their supply chain, are negatively impacting the manufacturers of radiation-hardened electronics based in the US and Europe. This could result in a supply-demand imbalance, resulting in a negative impact on the growth of the market. However, the market is expected to recover slowly in the next 2 years and will grow at a CAGR of 3.5% from 2020 to 2026.

The growth in North America is attributed to the large presence of leading companies such as Honeywell Aerospace & Defense (US), Microchip Technology (US), and Xilinx, Inc. (US) and renowned space research institutes such as the National Aeronautics and Space Administration (NASA), the Florida Space Research Institute (FSRI), and Keck Institute for Space Studies (KISS). Most of the rad-hard components (nearly 50%) are supplied by the US to several parts of the world, and despite the stagnant economic growth and DoD budget costs, the demand for radiation-hardened electronics products is expected to remain high owing to various space missions and military operations being conducted worldwide. On the other hand, Europe is also expected to represent promising opportunities for the rad-hard component manufacturers during the forecast period. The market in APAC is expected to register the highest CAGR in the rad-hard market. With cutting-edge manufacturing technological abilities and improving economic conditions in China, India, and Japan, the region is expected to witness high growth in the coming years.

The key players in the global radiation-hardened electronics market include Analog Devices Inc., BAE System, Cobham PLc, Honeywell, IBM, Infineon Technologies (Germany), Microchip technology (US), Renesas Electronics (Japan), STMicroelectronics (Switzerland), Texas, Boeing, Xilinx Inc., Maxwell, Psemi Corporation, Teledyne E2v Semiconductors, 3d Plus, Micropac Industries, Inc, Anaren Inc, Tt Electronics Plc, Data Device Corporation (Transdigm), and Solid-State Devices, Inc. (SSDI).