Implementation of Relay-Based Emergency Communication System on Software Defined Radio

The loss of communication system during natural disaster is known to hamper the efficiency of disaster response. In most cases, the paralyzed communication system often appears as one of the factors which delays the disaster response and complicates the rescue operation. However, if the communication systems including the mobile network are in working conditions, they are usually congested. Hence there is a need for an improved emergency communication system (ECS) to provide reliability and improve system performance during emergency. Furthermore, most of the works on ECS are based on theoretical simulations which can not capture the real world scenario. Taking into account the structure of the internet of things, which includes sensing, computing and communicating, this paper presents an ECS which consists of a wireless relay node, a disaster sensing and detection system. The relay node serves as a temporary communication station to help victims equipped with mobile phones to maintain a reliable communication link with the next available base station in the vicinity. Meanwhile, the sensors are used to detect abnormal changes in environmental parameters such as temperature and water level. The design is implemented on software defined radios. The simulated and measured results shows significant improvement in terms of data and bit error rate over the direct communication scheme.