FPGA-Based Wireless Link Emulator for Wireless Sensor Network

Abstract

Wireless sensor testbeds lack the flexibility for topology control and the accuracy for interference generation. Once the testbed is set up, the topology becomes fixed. Due to the nature of the wireless environment, experimenters often suffer from unpredictable background interference, while at the same time, find it hard to get accurate and repeatable interference sources. The wireless link emulator addresses these issues by replacing the uncontrollable wireless link by a well-controlled and programmable hardwired medium. A radio interface is then made to behave according to the link configuration, thus offering flexibility for both topology and interference control. This paper describes the implementation of the wireless link emulator based on a number of low-cost Xilinx FPGAs. The system is verified experimentally and compared to existing emulation systems.