A Comparison of Scheduling Approaches in Modular Software Defined Radio

摘要

The understanding of design approaches and operating conditions for Modular Software Defined Radio (Mod-SDR) are of immediate relevance for offering flexible services to mobile users, by means of a single communication device. Both the potential of modular hardware/software for short time to market and the capability of mastering diverse data transmission modes under a unified multiprocessing framework are the motivation for research efforts in this field. The paper in hand introduces Half-Frame Pipelining (HFP) as a method for scheduling software modules on a particular two-processor hardware. HFP requires partitioning of directed acyclic graphs capturing the logical structures of a Mod-SDR. A novel way of determining edge cost allows to solve the problem by spectral partitioning. We compare the properties of HFP with those of Graph Duplication Pipelining (GDP), which we have found to be an optimal scheduling method with respect to speedup and delay for circuit-switched services. Based on computer simulations we conclude on the utility of these scheduling methods under different operating conditions for Modular Software Defined Radio.