On the Optimization of Real Time Performance of Software Defined Radio on Linux OS

Zhen Wang, Limin Xiao, Xin Su, Xin Qi, Xibin Xu

State Key Laboratory on Microwave and Digital Communications, Tsinghua National Laboratory for Information Science and Technology, Research Institute of Information Technology, Tsinghua University, Beijing, China.

DOI: 10.4236/cn.2013.53B2054                

Abstract

With the evolution of the communication standards, Software Defined Radio (SDR) is faced with an increasingly important problem to balance more and more complex wireless communication algorithms against relatively limited processing capability of hardware. And, the competition for computing resources exacerbates the problem and increases time-delay of SDR system. This paper presents an integrated optimization method for the real-time performance of SDR on Linux OS (operating system). The method is composed of three parts: real-time scheduling policy which ensures higher priority for SDR tasks, CGROUPS used to manage and redistribute the computing resources, and fine-grade system timer which makes the process preemption more accurate. According to the experiments, the round-trip data transfer latency decreases low enough to meet the requirement for TD-SCDMA via the application of the method.

Keywords

SDR; Real-time Priority; CGROUP; System Timer

Conflicts of Interest

The authors declare no conflicts of interest.

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