Testbed for evaluating Wireless Sensor Networks with non-line of sight links

The paper presents a testbed for Wireless Sensor Networks (WSN) located at Universidad del Norte in Barranquilla Colombia, created for testing different communication protocols in a real scenario with non-line of sight (NLOS) links and interference. The testbed uses XTend RF Modules at 900MHz, with 1 mW transmission power, and covers an area of 11,000 m2. Results show that the testbed has propagation characteristics difficult to reproduce in testbeds present in the literature. Experiments demonstrate testbed performance regarding path loss, average packet loss and number of duplicates. Despite poor performance of links in the network, percentage of successful packet reception in the sink node was 70%, using a controlled flooding protocol with 8 nodes. Testbed implemented is a real scenario for WSN applications where nodes are deployed randomly to cover a determined area. Given the radio employed, the testbed has the possibility of extending experiments to long range applications.