UAS (Unmanned Aerial Systems) are commonly used in 3D (dull, dirty and dangerous) missions, because these are not endangering the operators life, while reduce maintenance costs and increase maneuvering capabilities. Despite of these advantages we should consider the possible vulnerabilities of this technology as well. Unmanned vehicles can be controlled via direct communication link, or they can work in a preprogrammed mode. Usually the preprogrammed mode is based on radio navigation systems, so we can draw a conclusion that both depend on the RF environment. In this paper I analyze a possibility to effectively evaluate the communication link of an UAS. Developers have to consider several key factors (type of operation, endurance, payload type and size, propulsion, communication link, etc.) during the development process. They are also responsible that the final product meets the predefined requirements. On the other side commercial UAS owners should have a possibility to compare and evaluate the UAS before the acquisition. Finally, operators and frequency management entities need tools to diagnose the possible sources of interference regarding the unmanned vehicles. To understand the consequences of interference in the RF spectrum we have to be able to measure the quality of the communication link in different usage scenarios. In my research I evaluate the usage of SDRs (Software Defined Radios) in RF Test and Evaluation processes. After analyzing the possibilities for a flexible testbed, I demonstrate the usability with some measurements in the GNU Radio signal processing framework.
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 Kerns A. J. “Unmanned aircraft capture and control via gps spoofing” http://radionavlab.ae.utexas.edu/images/stories/files/papers/unmannedCapture.pdf.
 United States Air Force Scientific Advisory Board “Report on operating next-generation remotely piloted aircraft for irregular warfare” Section 2.4.2 http://info.publicintelligence.net/USAF-RemoteIrregularWarfare.pdf 2011.
 Federal Aviation Administration “Laser hazards in navigable airspace” https://www.faa.gov/pilots/safety/pilotsafetybrochures/media/laser_hazards_web.pdf.
 Makkay I. “Fight of drones” (“Drónok harca”) 2015 http://www.repulestudomany.hu/folyoirat/2015_1/2015-1-05-0192-Makkay_Imre.pdf.
 Bob Kerczewski Jeff Wilson Bill Bishop – “Frequency Spectrum for Integration of Unmanned Aircraft” NASA http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6719706.
 Yanmaz E.; Kuschnig R.; Bettstetter C. “Channel Measurements over 802.11a-based UAV-to Ground Links” http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=6162389&abstractAccess=no&userType=inst.
 Steve Gardner “A communication link reliability study for small unmanned aerial vehicles” Enerdyne Technologies Inc.-COMM OPS Trends in Communication Systems For ISR UAVs January 2009 http://www.milsatmagazine.com/story.php?number=893938022.
 Pywell M. Midgley-Davies M. “EW test and evaluation - assuring survivability and operational effectiveness” Electromagnetic Engineering Department BAE SYSTEMS Military Air & Information http://tangentlink.com/wp-content/uploads/2014/07/2.-Electronic-Warfare-Test-Evaluation-Mitch-Midgley-Davies.pdf.
 Miko G. Nemeth A. “Combined communication and radio navigation system for small UAVs” Radioelektronika 2013 23rd International Conference pp. 284-288 ISBN: 978-1-4673-5516-2.
 Turan M. Gunay F. Aslan A. “An analytical approach to the concept of counter-UA ops (CUAOPS)” Journal of Intelligent & Robotic Systems January 2012 Volume 65 Issue 1-4 pp 73-91 ISSN 1573-0409 http://link.springer.com/article/10.1007%2Fs10846-011-9580-6.
 Zheng Y. Wang Y. “Hardware in the Loop Simulation for Low-altitude UAV Link in the Complex Terrain” Applied Mechanics and Materials Vols. 336-338 (2013) pp. 1907-1912 ISBN:9783037857519.
 Yanmaz E.; Bettstetter C. “ Channel measurements over 802.11a-based UAV-to-ground links” GLOBECOM Workshops (GC Wkshps) IEEE 2011 ISBN:978-1-4673-0039-1.
 Wan J. Suo H. Yan H. Liu J. “A general test platform for cyber-physical systems:unmanned vehicle with wireless sensor network navigation” 2011 International Conference on Advances in Engineeringhttp://ac.els-cdn.com/S1877705811054658/1-s2.0-S1877705811054658-main.pdf?_tid=3c747952-6b8b-11e5-bae9-00000aab0f6b&acdnat=1444068326_18bdf0fe9b500d0fcc69e141753afc30.
 Koepke G. Young W. Ladbury J. Coder J. “Complexities of testing interference and coexistence of wireless systems in critical infrastructure” 2015 http://nvlpubs.nist.gov/nistpubs/TechnicalNotes/NIST.TN.1885.pdf.
 Slater D. Tague P. Poovendran R. Li M. “A game-theoretic framework for jamming attacks and mitigation in commercial aircraft wireless networks” http://www.ee.washington.edu/research/nsl/papers/aiaaInfotech09c.pdf.
 Jamshidi M. Jaimes Betancourt A. S. Gomez J. “Cyber-physical control of unmanned aerial vehicles” http://ac.els-cdn.com/S1026309811000691/1-s2.0-S1026309811000691-main.pdf?_tid=71385718-66c6-11e5-9137-00000aab0f6b&acdnat=1443543999_0cc41af19de0b2765c48bdb1e55402c3.
 Saeed A. Neishaboori A. Mohamed A. Harras K. A. “Up and away: a cheap UAV cyber-physical testbed” http://arxiv.org/pdf/1405.1823v1.pdf.
 Department of the Army “Cyber electromagnetic activities field manual no. 3-38” Washington DC 12 February 2014 http://armypubs.army.mil/doctrine/DR_pubs/dr_a/pdf/fm3_38.pdf.
 Zainudin A. Sudarsono A. Astaw I. G. P. “Reliability analysis of digital communication for various data types transmission using GNU Radio and USRP” http://www.researchgate.net/publication/259477837_Reliability_Analysis_of_Digital_Communication_for_Various_Data_Types_Transmission_Using_GNU_Radio_and_USRP.
 Javaid A. Sun W. and Alam M. “A Cost-Effective Simulation Testbed for Unmanned Aerial Vehicle Network Cyber Attack Analysis” Safe & Secure Systems & Software Symposium (S5) June 9-11 2015 http://www.mys5.org/Proceedings/2015/Day_3/2015-S5-Day3_0805_Sun.pdf.
 Ettus Research Application Note “Selecting an RF Daughterboard” http://www.ettus.com/content/files/kb/Selecting_an_RF_Daughterboard.pdf.
 Tucker T.W. “Jammer testing and chaos” Tactical Technologies Inc.http://ttiecm.com/uploads/resources_technical/jammer%20testing%20and%20chaos.pdf.
 Chen J. Zhang S.† Wang H. Zhang X. “Practicing a record-and-replay system on USRP” Sigcomm Conference 2013 http://conferences.sigcomm.org/sigcomm/2013/papers/srif/p61.pdf.
 O’Shea T. “GNU Radio channel simulation: trolling sub-par modem algorithms and implementations for fun and profit” Research Faculty Virginia Polytechnic Institute and University Arlington VA 1 Oct 2013 http://static1.1.sqspcdn.com/static/f/679473/23654472/1381240802597/grcon13_oshea_chansim.pdf?token=iRbiWsmfTNpfPqITN708izU3fQU%3D.
 Department of Electrical and Computer Engineering Ben-Gurion University of the Negev “Introduction to USRP” http://www.researchgate.net/file.PostFileLoader.html?id=545b5550d039b12d7c8b4567&key=80f8366d-3355-40ad-a657-7ffb6b904ff8&assetKey=AS:272121316478982@1441890186007.
 Ettus Research “Latency” https://github.com/EttusResearch/uhd/wiki/Latency.
 Brown A. Tredway R. and Taylor R. “GPS signal simulation using open source GPS receiver platform” https://wireless.vt.edu/symposium/2011/posters/GPS%20Signal%20Simulation_Brown.pdf.
 Knudsen J. Varpiola M. “What is fuzzing: the poet the courier and the oracle” 2015 http://www.codenomicon.com/resources/white-paper/pdf/WhatisFuzzing.pdf.
 “Hijacking DJI Phantom 2 Vision and P2V+” https://github.com/noahwilliamsson/dji-phantom-vision.
 Cencini A. Yu K. Chan T. “Software vulnerabilities: full- responsible- and non-disclosure” December 7 2005 http://courses.cs.washington.edu/courses/csep590/05au/whitepaper_turnin/software_vulnerabilities_by_cencini_yu_chan.pdf p. 10.