TELFOR 2015, Belgrade, Serbia, November Spectrum Sensing for the Unlicensed Band Cognitive Radio Nenad Milošević, Zorica Nikolić, Filip Jelenković, Valentina Nejković, Milorad Tošić, Ivan Šeškar

2 TELFOR 2015, Belgrade, Serbia PRESENTATION OUTLINE Introduction LTE-Advanced Unlicensed bands and dynamic spectrum access Experiment design and results Conclusion

3 TELFOR 2015, Belgrade, Serbia PRESENTATION OUTLINE Introduction LTE-Advanced Unlicensed bands and dynamic spectrum access Experiment design and results Conclusion

4 TELFOR 2015, Belgrade, Serbia INTRODUCTION Rapid growth of mobile communications industry Almost completely based on the usage of licensed spectrum 1000 times cellular data traffic growth until 2020 Use some additional spectrum out of the dedicated licensed band Long-term evolution (LTE) was first defined in 3GPP R8 Provides high data rates, higher capacity Further improved in 3GPP R10 – LTE-Advanced Carrier Aggregation Spectrum sensing

5 TELFOR 2015, Belgrade, Serbia PRESENTATION OUTLINE Introduction LTE-Advanced Unlicensed bands and dynamic spectrum access Experiment design and results Conclusion

6 TELFOR 2015, Belgrade, Serbia LTE-ADVANCED New functionalities Enhanced use of multi-antenna techniques and support for Relay Nodes Carrier Aggregation R8 LTE carrier bandwidths: 1.4, 3, 5, 10, 15, and 20 MHz R10 LTE – Combination of up to 5 carriers Maximum bandwidth of 100 MHz

7 TELFOR 2015, Belgrade, Serbia LTE-ADVANCED LTE-A Carrier Aggregation

8 TELFOR 2015, Belgrade, Serbia LTE-ADVANCED Three types of carrier aggregation

9 TELFOR 2015, Belgrade, Serbia PRESENTATION OUTLINE Introduction LTE-Advanced Unlicensed bands and dynamic spectrum access Experiment design and results Conclusion

10 TELFOR 2015, Belgrade, Serbia UNLICENSED BANDS AND DYNAMIC SPECTRUM ACCESS ISM (Industrial, Scientific and Medical) bands (900, 2400, 5800 MHz) U-NII (Unlicensed National Information Infrastructure) band (5 GHz) Unlicensed spectrum regulations Dynamic Frequency Selection Transmit Power Control Avoid interference with weather-radar and military applications

11 TELFOR 2015, Belgrade, Serbia UNLICENSED BANDS AND DYNAMIC SPECTRUM ACCESS An overview of 5 GHz unlicensed band

12 TELFOR 2015, Belgrade, Serbia UNLICENSED BANDS AND DYNAMIC SPECTRUM ACCESS Spectrum and interference coordination Unlicensed spectrum - a fair coexistence of LTE and other technologies Upon the unlicensed spectrum usage  LTE network observes the spectrum  Selects the channel with the least interference  Dynamically adjusts for the continued interference avoidance

13 TELFOR 2015, Belgrade, Serbia UNLICENSED BANDS AND DYNAMIC SPECTRUM ACCESS Spectrum sensing (SS) and Spectrum Coordination  Who performs SS?  What to do with the measurements? Two general approaches to spectrum coordination  Reactive Spectrum Coordination Station adapts its parameters as a reaction to the changes in the wireless environment Standalone or coordinated  Proactive Spectrum Coordination Control channel is used for periodical exchange of spectrum usage information

14 TELFOR 2015, Belgrade, Serbia PRESENTATION OUTLINE Introduction LTE-Advanced Unlicensed bands and dynamic spectrum access Experiment design and results Conclusion

15 TELFOR 2015, Belgrade, Serbia EXPERIMENT DESIGN AND RESULTS Wideband Software Extensible Radio Platform (WiSER)

16 TELFOR 2015, Belgrade, Serbia EXPERIMENT DESIGN AND RESULTS defProperty('resS', 'omf.nitos.node57', "ID of sensor node") defProperty('res1', 'omf.nitos.node53', "ID of 1st WiFi node") defProperty('res2', 'omf.nitos.node61', "ID of 2nd WiFi node") defProperty('duration', 10, "Duration")

17 TELFOR 2015, Belgrade, Serbia EXPERIMENT DESIGN AND RESULTS defGroup('Sender', property.res1) do |node| node.addApplication("otg2app") do |app| app.setProperty('udp:local_host', ' ') app.setProperty('udp:dst_host', ' ') app.setProperty('udp:dst_port', 3000) app.measure('udp_out', :samples => 1) end

18 TELFOR 2015, Belgrade, Serbia EXPERIMENT DESIGN AND RESULTS defGroup('Sensor', property.resS) do |node| node.addApplication("wiserd-wrapper") do |app| app.setProperty('uhd_rx_rate', '10E6') app.setProperty('uhd_rx_freq', '2.437E9') app.setProperty('uhd_rx_gain', '40') app.setProperty('recv_numbins', '64') app.setProperty('recv_avgwinlen', '28') app.setProperty('recv_running_time', (2000).to_s) app.setProperty('timed', '') app.setProperty('recv_oml_output_type', 'vector') app.setProperty('recv_oml_servername', 'file:res.txt') app.setProperty('fftmovingavgoml', '') end

19 TELFOR 2015, Belgrade, Serbia EXPERIMENT DESIGN AND RESULTS onEvent(:ALL_UP_AND_INSTALLED) do |event| info "This is OMF-WiFi-USRP-wiserd experiment" wait 10 group("Sensor").startApplications wait property.duration*5 group("Sensor").stopApplications wait property.duration*2 group("Receiver").startApplications group("Sender").startApplications wait property.duration*2 group("Sensor").startApplications wait property.duration*2 allGroups.stopApplications Experiment.done end

20 TELFOR 2015, Belgrade, Serbia EXPERIMENT DESIGN AND RESULTS Sensed spectrum

21 TELFOR 2015, Belgrade, Serbia EXPERIMENT DESIGN The goal is to support experimentation with LTE in the unlicensed 5 GHz band with coexisting devices using other technologies. LTE hardware implementation operating in the unlicensed 5 GHz band does not exist yet 5 GHz LTE station will be emulated by USRP

22 TELFOR 2015, Belgrade, Serbia PRESENTATION OUTLINE Introduction LTE-Advanced Unlicensed bands and dynamic spectrum access Experiment design Conclusion

23 TELFOR 2015, Belgrade, Serbia This paper described the spectrum sensing experimentation at NITOS testbed within the NITLab at the University of Thessaly, Greece. The experiments have shown that the WiFi activity may be identified and therefore coordinated with other systems operating in the unlicensed band. The next step is to develop the experimentation platform that will include both LTE and WiFi devices operating in the unlicensed 5 GHz band. The goal is to enable coordination between the users and to determine performance of such a system. CONCLUSION

24 TELFOR 2015, Belgrade, Serbia CONCLUSION

25 TELFOR 2015, Belgrade, Serbia