SINR based routing for Mobile Ad-hoc Networks

Mobile Adhoc Networks (MANETs) are self-organizing and self-configuring multi-hop wireless networks capable of adaptive re-configuration as effected by node mobility. In such wireless networks, there can be different sources of noise which can be interpreted falsely as a signal which may lead to several undesired consequences. It is imperative if such noise and interferences are separated from actual signal and thereby making the communication system more efficient. In this work, we propose a system which eliminates the noisy signals received at the physical layer by comparing the signal to interference noise ratio with the signal to noise threshold value. Interference and noise signal along with actual signal strength parameters are measured at physical layer of OSI reference architecture. Ratio of these two parameters (SINR) is calculated and is cross layered to the routing layer as a cross layer parameter. In routing layer, we maintain a signal to interference noise ratio threshold value (SINRT). SINR is compared with SINRT to select or discard the corresponding received message. If the received message has SINR which is less than the threshold value, such messages are discarded. If message has higher SINR when compared with SINRT, then it is selected for further processing. We implemented this by making changes to AODV protocol (CLAODV) using NS2 simulator. The resulting system makes links in CLAODV reliable and thereby increasing the throughput, packet delivery ratio and reducing the delay and overhead.