Analysis of path loss mitigation through dynamic spectrum access: Software defined radio

In this paper, an analysis is carried out for a method to mitigate the path loss through the dynamic spectrum access (DSA) method. The path loss is a major component which determines the QoS of a wireless link. Its effect is complemented by the presence of obstruction between the transmitter and receiver. The future cellular network (5G) focuses on operating with the millimeter-wave (mmW). In higher frequency, path loss can play a significant role in degrading the link quality due to higher attenuation. In a scenario, where the operating environment is changing dynamically, sudden degradation of operating conditions or arrival of obstruction between transmitter and receiver may result in link failure. The method analyzed here includes dynamically allocating spectrum at a lower frequency band for a link suffering from high path loss. For the analysis, a wireless link was set up using Universal Software Radio Peripherals (USRPs). The received power is observed to increase by dynamically changing the operating frequency from 1.9 GHz to 830 MHz. Finally the utility of software defined radio (SDR) in the RF front end, to combat the path loss in the future cellular networks, is studied.