Cognitive radios allow the increase in the spectrum efficiency through flexible spectrum use. CR nodes can search for unused portions of the radio spectrum and communicate over those vacant radio frequencies.
Researchers at WIT, Dehradun, used NetSim to simulate cognitive sensing, i.e the CPEs (SUs) sense the spectrum and send periodic reports to the BS informing it about what they sense. The BS, with the information gathered, detects Primary User (PU) activity.
Enhancing the efficiency of CR networks: Development of new sensing algorithms for better detection of primary users.
Developing custom code: Users can write their own algorithms by modifying NetSim Source C codes. Some of the important files are 802.22.c, SpectrumManager.c, OFDMA.c, DSFrame.c, DSMAP.c, USFrame.c, USMAP.c and Incumbent.c.
Modeling network configurations: A variety of network configurations were created using NetSim’s GUI and XML based network configuration files. Simulation parameters were set per the experiment set-up.
Generating performance metrics: NetSim 802.22 library provides specialized output metrics such as Spectral efficiency, SCH sent/received, FCH sent/received, UCS sent, Primary User – Operational time, Idle time and interference time. Packet and event traces were also used for calculating the sought performance graphs.
Some examples of the publications completed using NetSim include –
- Jyotsana Kanti, Ashish Bagwari, Geetam Singh Tomar, “Quality Analysis of Cognitive Radio Networks based on Modulation Techniques“, IEEE International Conference on Computational Intelligence and Communication Networks (CICN 2015)
- Ashish Bagwari, Jyotsana Kanti, Geetam Singh Tomar, “Smart Detection Technique for IEEE 802.22 Standards“, Global Conference on Wireless & Optical Communications (GC WOC 18)
- Ashish Bagwari, Jyotsana Kanti, Geetam Singh Tomar, “New Detector to Enhance Cognitive Radio Performances“, IEEE International Conference on Computational Intelligence and Communication Networks (CICN 2018)
Based on the success of more than four batches of researchers, WIT in 2018, upgraded NetSim and purchased additional licenses to cater to the Research needs of for their Ph.D. Scholars.
“We evaluated other products such as NS-2, NS-3, Qualnet and OMNET but chose NetSim given its extensive R & D capabilities in 802.22 Cognitive Radio. In addition, the other simulators were too expensive with annual license purchases, support contracts etc.
NetSim source code is easy to understand and debug and NetSim is also well recognized in the research community. This coupled with onsite/helpdesk/phone-based technical support enabled us to publish our papers in time”