What is the SCA (Software Communications Architecture) standard for military SDR?

The Software Communications Architecture (SCA) is a US Department of Defense open software framework standard that defines a common operating environment (OE) for software defined radios used in military tactical communications. The SCA's primary purpose is to enable waveform portability: a communication waveform (the software that implements a specific radio protocol, such as SINCGARS, MUOS, or Link 16) developed once can be deployed on any SCA-compliant radio hardware platform from any vendor without modification. The SCA defines: a Core Framework (CF) that provides standardized interfaces for waveform deployment, configuration, and lifecycle management; a hardware abstraction layer that isolates waveform software from specific radio hardware (processors, FPGAs, RF front-ends); middleware based on CORBA (Common Object Request Broker Architecture) for inter-component communication across processors; and a domain profile that describes the radio hardware capabilities in an XML-based format. The SCA was developed by the Joint Tactical Networking Center (JTNC, formerly JTRS JPO) and is used across the US military's Joint Tactical Radio System (JTRS) and allied nations' tactical radio programs. SCA 4.1 (released 2017) modernized the standard, replacing CORBA with a lighter-weight middleware option and improving support for modern processing architectures.