MicroTCA looks set to make military impactStory
February 24, 2007
MicroTCA looks set to become the first serious contender to bridge the gap between the telecommunication and military markets, and could provide the breakthrough for standards-based, embedded computing into the military communications infrastructure that will become the backbone of the digital battlefield and the GIG.
Military embedded computing applications have tended to shun telecommunications equipment standards, creating two major markets for embedded computing manufacturers to serve. Telecommunication standards are intended for static, temperature-controlled environments, using large module sizes and, particularly in the case of the value-added service providers, employing rapid technology churn to achieve year-on-year cost efficiencies for their services. Out of this rapid technology evolution, new standards have emerged for telecommunications-oriented embedded computing in the form of the Advanced Telecom Computing Architecture (AdvancedTCA) and its associated standard for the Advanced Mezzanine Card (AdvancedMC). MicroTCA takes AdvancedMC one step further by creating from it a small form factor, fabric-based embedded computing architecture that will have broad appeal in many more markets than its telecom progenitor, including a host of traditional and new military applications.
AdvancedMCs can be produced in two basic sizes with options on width: a single module of approximately 3" x 7" and a double-size module of approximately 6" x 7". They are mounted on carriers that plug into an AdvancedTCA racking system using high-speed serial connections such as PCI Express or Ethernet to interconnect with AdvancedTCA modules in the rack. AdvancedMCs
are often used to provide the multitude of external connections and protocols found in telecom systems, providing a very flexible way of mixing and matching an AdvancedTCA system to the user’s requirements.
MicroTCA dispenses with the bulky AdvancedTCA equipment practice, instead inserting AdvancedMC modules directly into a backplane mounted in a 300 mm practice racking system that supports levels of size and complexity ranging from just one or two single-size AdvancedMCs to large mixed configurations of single- and double-size modules. Without the supporting environment of AdvancedTCA, MicroTCA needs its own form of power and system management plus a high-speed fabric switch, which is provided by a MicroTCA Carrier Hub (MCH). An MCH occupies a single backplane slot supporting up to 12 MicroTCA backplane slots. Keys to the success of MicroTCA include its size, performance, scalability, support for different fabrics (PCI Express, Ethernet, and Serial RapidIO), and high-availability capabilities, such as multiple redundancy with hot swap of modules, power supplies, and cooling. Figure 1 illustrates MicroTCA’s main architectural features.
Significance to the military
VME and, to a lesser extent, CompactPCI prod-ucts have dominated the COTS era for embedded computing so far. Many of these have found their way into high-profile, very rugged applications in main battle tanks, armored vehicles, combat aircraft, helicopters, Unmanned Aerial Vehicles (UAVs), and weapons systems of many types. Experience has shown that the 6U form factor of VME and CompactPCI offers the ideal balance of size, power capacity, performance, functionality, and ruggedness for many military applications, making the double-size format of MicroTCA potentially attractive for these applications. The introduction of new fabrics plus demands for more performance and connectivity have pushed the current standards to their limits, ushering in a time for reevaluation and step changes of technology to stay at the cutting edge. In the case of VME, two new standards have emerged: VITA 41 (VXS) and, for more ruggedized applications, VITA 46 (VPX). These new standards introduce fabric-centric capability to VME products similar to MicroTCA, enabling VME to continue offering the ruggedized military market the required performance and specialized connectivity for some considerable time to come.
The recent successes of 3U CompactPCI in rugged military applications underline the growing need for smaller form factors where space and weight are critical. Adding extra capability to existing weapons platforms and the development of smaller, lighter UAVs are primary application areas for 3U CompactPCI today. But these application areas where VME and CompactPCI excel are at the very rugged end of the environmental spectrum. Developing MicroTCA to meet these demanding conditions would be very costly, and its key benefits likely would not add any perceived operational value. Form factor and architecture have minimal effect on the price of a rugged embedded computer; pound for pound or cubic foot for cubic foot, the recurring purchase price will be the same if the same level of performance, functionality, and power dissipation is required.
MicroTCA’s high availability offers little additional benefit for many rugged applications. For example, a combat aircraft’s mission may last no more than a few hours, but during that time 100 percent reliability is essential. The equipment must operate flawlessly at all times throughout the platform’s operational envelope. Reliability is more important than high availability in this case because hardware and application software cannot be stopped and reconfigured if something goes wrong. Also, some classes of application are more suited to high availability and redundancy than others. Hardware redundancy works well for table-driven applications such as switches, routers, gateways, and concentrators but is excessively complex for intelligence-driven systems such as mission computers, flight control systems, and artificial intelligence applications. These require duplicate execution and synchronization at the operating system level and regular comparative checks of results.
Military application potential
MicroTCA does not have to compete with the established leaders in these rugged markets to be successful. Many other more directly suitable markets exist or are emerging that VME and CompactPCI will not be able to address as effectively. Existing markets include naval combat systems, both for submarines and surface ships as well as manned surveillance aircraft with pressurized work areas. Topping the list of product selection criteria for these systems are reasonable product longevity, tightly controlled configuration management, and long-term evolutionary road maps.
Mission times for naval vessels can extend to many months during which maintenance and repair activities must be carried out with minimum disruptions, so maintainability and availability are key features. These systems can use predominantly commercial grade products as their environment is carefully controlled. Open standards are vital for integrating the combat system with the many other systems found on these platforms, including sensors, weapons, Electronic Warfare (EW), self-defense, communications, propulsion, and navigation. Today VME is used extensively in this market because it offers many operational advantages over, for example, PCs or boxed servers. MicroTCA can offer these same advantages plus high availability and projected price point benefits.
With the advent of spiral development principles and the introduction of planned, regular technology refreshes, many programs operating in protected environments are learning to use the latest commercial technologies to their advantage. Defense policy aims to make technological superiority the ultimate advantage, but operational considerations often prevent deployment of the latest hardware. Excluding the specialized display requirements of combat systems, the embedded computing elements could be implemented using commercial grade PCs and servers regularly refreshed with the latest high street offerings. Cost is a big enabler of technology refresh. With its high levels of functionality and performance supported by its volume telecom market, MicroTCA is projected to offer rapid technology cycles and competitive price points that will make more consistent technology refresh both a necessary and affordable reality.
The development of the Global Information Grid (GIG) and the Internet-like information battlefield of the future have highlighted the demand for ever-more bandwidth in the field and integration of the many diverse fighting and intelligence-gathering platforms from all the services. The Army’s command structure of the future will have access to unprecedented amounts of information in the form of digital voice, data, and video from a multitude of sources. MicroTCA is ideally suited to the Army’s need to develop its communications infrastructure and to satisfy its thirst for increased bandwidth via its satellite network. Mobile installations on trucks, containers, and Humvees such as command posts, UAV ground stations, and satellite terminals are all candidate applications. The broad range of functions available off-the-shelf in AdvancedMCs for the telecom market make implementation straightforward using well-proven building blocks and software. Figure 2 illustrates a range of AdvancedMC modules produced by GE Fanuc Embedded Systems, ready to serve mobile military communications applications. MicroTCA’s small size means it can be protected from the external environment by cocooning without the expense of complete ruggedization, making it practical to implement in large numbers.
Road to deployment
Of course, MicroTCA cannot march out of the wire center straight to deployment. For many market segments, specialized interfaces will be required as well as environmental assessment and enhanced packaging. PCI Express and Serial RapidIO will be the key enablers to meeting the military interface and graphical display performance challenges. MicroTCA looks set to become the first serious contender to bridge the gap between the telecommunication and military markets, and could provide the breakthrough for standards-based, embedded computing into the military communications infrastructure that will become the backbone of the digital battlefield and the GIG.
To learn more, e-mail Duncan Young at