SCA Overview

Software Communication Architecture

Software re-programmable devices that can be reconfigured to adapt to changing product developments are within reach, enabling rapid transformation of those products at much lower cost and much quicker than today’s conventional approach of developing a new product based on hardware modifications.

A key element of any software-based system is the overall software architecture that development teams follow to integrate the software to the hardware platform. In most cases, still today, organizations make use of proprietary software architectures that tightly couple software applications to the hardware platforms. With changes of platforms (through hardware evolution for example), the software often needs to be significantly modified to adapt to the new characteristics of the hardware, adding additional cost and time-to-market to the product. This unique and proprietary approach is also prone to obsolescence when the original team members move on to other projects, positions or companies.

The Software Communications Architecture (SCA) is an open standard, developed by the international radio community to alleviate those drawbacks and make the development of Software Defined Products more efficient, thus reducing time-to-market and development cost and improving product quality and performance.

  • What is the SCA?

    The Software Communications Architecture (SCA) is an open architecture framework that promotes development of “Software Defined” systems by clearly identifying the boundaries for software applications and their interactions with the physical hardware. The SCA facilitates the portability, interoperability and configurability of the software and hardware components used in embedded systems.

    The SCA was originally developed by the U.S. military’s Joint Tactical Radio Systems (JTRS) to standardize the way in which Software Defined Radios (SDR) for the U.S. armed forces were to be built. Since then, the SCA has evolved with the input of the international radio community led by the Wireless Innovation Forum (WInnF).

    Component Based Development (CBD)

    The SCA follows a Component Based Development (CBD) paradigm where software applications (i.e., waveform applications) are assembled using a number of individually built (and tested) components. The SCA is a CBD architecture that provides location transparency as well as operating system and programming language independence for its software components. Being a key goal of the SCA to promote software reuse, application components are ‘shielded’ on their interaction with the physical hardware through an abstraction layer that offers standardized interfaces as proxies to the physical hardware. The latter in turn promotes application portability from one platform to another.

    The SCA Core Framework (CF), a key element of the architecture, provides a standard operating (OE) that is identified by the combination of Operating System (OS), Processor and CORBA ORB for inter process communication. The SCA CF is a runtime deployment engine that identifies requirements of software components, and matches them with suitable targets for deployment within the SCA system. Requirements can take the form of capabilities of a platform like processor type (GPP, DSP, GPU, FPGA), or finite capacities like memory or mips needed for execution.

    The SCA OE shields the SCA Application from changes in the underlying software/hardware by abstracting the deployment platform. The SCA does so for the physical hardware devices used by the SCA Application, the operating systems that runs on the target, as well as the inter process communication mechanism used by the different components executing on the platform.

  • SCA History

    The Software Communications Architecture (SCA) was originally created by the Modular Software programmable Radio Consortium (MSRC): RaytheonBAE SystemsRockwell Collins, and ITT, under contract to the U.S. Department of Defense Joint Tactical Radio System (JTRS) Joint Program Office (JPO).

    SCA version 1.0 was first introduced early in the year 2000 and was followed by revisions that culminated in the release of SCA v 2.0 later that same year. 2001 saw the release of version 2.2, time at which the specification was deemed ‘implementable’. With the knowledge gained by implementations developed during the newt two years, the specification was updated to version 2.2.1 in 2004. Version 3.0 was released later that same year, but work on such version was stopped one year later. Focus was returned to improve version 2.2.1, and version 2.2.2 saw the light of day in the year 2006. With more lessons learned through the following years, in 2009 work started towards the new version of the SCA. It was code named SCA Next, and 4.0 was released in 2012. The scope of improvements from version 2.2.2 to version 4.0 were substantial, and industry feedback identified backwards compatibility  issues that needed to be solved. Version 4.1 addressed those issues and was published in August 2015.

    VIAVI has the industry’s largest team of SCA experts that have implemented all major versions of the SCA specification. From version 0.3 back in the early 2000s, to SCA 2.1, 2.2, 2.2.1, 2.2.2 and now the latest version 4.1.

    SCA Evolution

  • SCA International Adoption

    SCA International Adoption

    Proven Performance In Deployed Systems

    • General Dynamics AN/PRC-154 Rifleman Radios – 19,000 Units Ordered, 190,000 planned
    • General Dynamics AN/PRC-155 – 3700 Units ordered
    • Harris AN/PRC-117G – 25,000 Units Deployed
    • Harris AN/PRC-152 – 160,000 Units Deployed
    • Thales AN/PRC148 JTRS Enhanced MBITR – 200,000 Units Deployed

    Other SCA Based Radios In Deployment

    • Harris Falcon III Radio Family
    • Rockwell Collins/Thales FlexNet
    • ViaSat/Rockwell Collins MIDS-JTRS
    • Raytheon (RT-1987 / ARC231, MAINGATE, NMT, FAB-T)
    • Rockwell Collins RT-840
    • Rohde & Schwarz R&S®SDTR Vehicular Tactical Radio
    • Selex ES Swave™ Family (HH, VM-3, MB-1, VB-1, VQ-1)
    • Thales (FlexNet, Fastnet, and Nextwave Families)

    SCA Based Waveforms – Deployed*

    • Easy II
    • FlexNet Waveform
    • HDR-AJ
    • Mobile User Objective System (MUOS)
    • PR4G-Fastnet
    • SATURN
    • Soldier Radio Waveform (SRW)
    • Soldier Broadband Waveform (SBW)
    • VHF/UHF Line of Sight (VULOS)
    • Wideband Networking Waveform (WNW)
    • Legacy Waveforms (COBRA, SATCOM 181/182/183/184,
    • SINCGARS, EPLRS, JTRS Bowman, Link-16 & HF)

    SCA Based Waveforms – In Development*

    • Coalition Wideband Networking Waveform (COALWNW)
    • ESSOR High Data Rate Waveform (HDRWF)

    *These lists are representative, not all-inclusive

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