DARPA SPECTRUM CHALLENGE Team MarmotE: Peter Volgyesi, Miklos Maroti, Peter Horvath, Sandor Szilvasi, Benjamin Babjak http://dtsn.darpa.mil/spectrumchallenge

CHALLENGE GOALS PRELIMINARY CHALLENGE OUTCOME ISIS TECHNOLOGY The DARPA Spectrum Challenge is a competition to Proprietary physical layer design featuring demonstrate a radio protocol that can best use a given • Highly power efficient, interference-resilient wideband communication channel in the presence of other single-carrier transmission dynamic users and interfering signals. • Extremely robust, innovative synchronization schemes The Challenge is not focused on developing new radio relying on novel algebraic constructions hardware, but instead is targeted at finding strategies for • Open-loop variable-rate retransmission algorithm for guaranteeing successful communication in the presence received power accumulation of other radios that may have conflicting co-existence • Optimized transmit spectrum objectives. • Innovations enable reliable operation under very low signal-to-noise ratio conditions while effectively Challenge timeline: hindering the communication of the competing team in • During the Qualification Hurdles (March 2013) the ISIS team, cooperative setting Team MarmotE qualified rank 5 out of the 90 teams that initially registered. • The contestants in the Preliminary Event (September 2013) included the 15 highest-scoring teams and three wildcard teams. • The Final Challenge competition (March 2014) is slated to follow the same structure as the preliminaries but award twice the prize money. Photo: DARPA Purdue , Raytheon Efficient Spectrum Individual The ISIS team won the competitive challenge undefeated and came in third in the cooperative tournament. WSL-NEU The winners pose with Dr. Arati Prabhakar, DARPA Director and Dr. Yifty Eisenberg, Program Manager MarmotE , ISIS Gator Wings Spartans San Jose State University COMPETITION FRAMEWORK Software-defined implementation in GNU Radio RxTx Individuals • FOSS software development toolkit that provides signal VT-Hume All the matches occurred on the ORBIT testbed at Rutgers University’s WINLAB, wasabi Individual processing blocks to implement software defined VT CogRad Virginia Tech which streamed the proceedings live to DARPA where contestants and The Orange Wireless government personnel watched the event unfold. Contestants submitted their radios Wireless Infidels Polytechnic Institute of NYU GTRI Research Institute competitive and cooperative designs as Linux image files in advance. MarmotE modules: Wildcats • High-performance real-time signal processing blocks Notre Spectrum Notre Dame University KPE Individual • SIMD optimizations for resource-critical tasks Tennessee Tech Telecom Tennessee Tech Buzz Radio Georgia Institute of Technology • Contributions to GNU Radio code base RULES OUTLOOK: FINAL CHALLENGE

Competitive tournament: In each match, two teams battle to Photo: DARPA Incorporating lessons learned from the preliminary event: dominate the spectrum, with the winner being the first to • Strive to increase spectrum efficiency transmit files of random data (or to successfully transmit the Competitive tournament: the final double WINLAB photo • Explore intentional jamming opportunities greatest proportion of the files) from a source radio to a elimination bracket • Prepare the design for more interactive challenges destination radio. Teams have to evade, jam and/or operate in • Create a dedicated cooperative radio design the presence of competitors’ signals within a defined 5 MHz • Add more effective and robust coding schemes portion of the radio spectrum. This tournament simulates To help competitors see how their software compared with other teams’ designs, WINLAB developed data visualization technology for conditions directly applicable to military communications, where radios must deliver high-priority data in congested and often DARPA that showed the specific radio frequencies each team used and their progress in transmitting the test file. Based on color-coded contested electromagnetic environments. spectrum occupancy patterns, watchers could see how the radios interacted and infer each team’s likely strategies in real time.

Cooperative tournament: In each match, three teams work together to share the spectrum and transmit their random data files in the shortest time. Teams can not coordinate in advance on Team MarmotE how to share the spectrum, so they have to develop and implement algorithms that enable their software-defined radios Art to communicate at a high rate while leaving spectrum for the other two teams to do the same. This tournament simulates conditions that might be encountered during coalition operations, and also has possible future commercial applications, : Levendovszky such as opportunistic, license-free exploitation of ”TV White Photo Spaces” for high data rate communications.

Photo: DARPA Photo: DARPA DARPA provided all teams with the same hardware (USRP N210 radios) to ensure that each team would win based on their software algorithms alone. The competitive finals as seen on the spectrum display Cooperative match featuring MarmotE