Challenges in Transition of Software Defined Radio Implementation from Bare Metal to Real-Time Operating System

Real-time embedded implementations like software defined radios (SDR) impose several challenges being priority-driven and mostly sequential. Such critical real time embedded applications require a significant level of intelligence for hardware resource management. This feature is inherently offered by off-the-shelf available real-time operating systems (RTOS). Most of the fragments of support code available are in the form of bare metal implementations and are associated with specific hard-ware. There is no absolute guideline for how to convert a real-time (RT) embedded application into one with the usage of RTOS. Matters become much trickier if one has to port the entire application software from bare metal hardware implementation to an operating system (OS) environment. In this paper, we investigate the implementation details and problems encountered in timer-based scheduler errors, while porting the SDR application to an RTOS. This paper uses customizable RTOS by Micrium (µC/OS-II) for SDR implementation on Motorolla’s Power PC (MPC-565). This paper also discusses the use of timers to strictly control the clock drifts and rollovers for such embedded systems. The discussion uses MPC-565 as an implementation platform, however, the recommendations and analysis apply to all processors in general.