Collabora've*monitoring** of*Air*Traffic*and*RF*spectrum:** - PowerPoint PPT Presentation

Collabora've*monitoring** of*Air*Traffic*and*RF*spectrum:** the**OpenSky*and*ElectroSense*projects* Fabio*Ricciato*(speaker),*on*behalf*of** Vincent*Lenders,*MaThias*Schaefer,*Domenico*Gius'niano,*Roberto*Calvo* *…*and*many*others* * Talk*at*ICTP*–IAEA*Workshop*on*Environmental*Mapping:* Mobilising*Trust*in*Measurements*and*Engaging*Scien'fic**Ci'zenry* Trieste,*10.*March*2017**

About*myself* Fabio*Ricciato* • Present* • – Associate*Professor*Faculty*of*Computer*and*Informa'on*Science,*University* of*Ljubljana,*Slovenia* – Living*in*Trieste* Past* • – Worked**at*Forschungszentrum*Telekomunica'on*Wien*(FTW),*Austria* – Worked*at*Univ.*of*Salento,*Italy* – Worked*at*Austrian*Ins'tute*of*Technology*(AIT),*Austria* – Studied*in*Roma,*Univ.*La*Sapienza*(MS’99,*PhD’03)** * Competence*Field:* Communica)on*Networks** • – Wired*&*Wireless,*local]*&*wide]area,*…* – Different*topics,*technologies,*layers** – System]oriented,*applica'on]oriented,*experimental** *

About*this*talk* • Presen'ng*Two*crowdsourced*networks* * • Ini'ated*and*funded*by*armasuisse**

About*Armasuisse* • Armasuisse*is*a* federal'agency'of'the'Swiss'Confedera4on .*It*is* the* procurement * organiza)on* for* armaments* of* Switzerland* and*is*affiliated*with*the*Federal*Department*of*Defence,* Civil' Protec4on' and* Sport.* It* employs* around* 750* people.* It* is* responsible* for* research ,* development,* evalua)on,* procurement,* maintenance* and* liquida)on* of* materials* and* construc)on*of*the*Swiss*Army.** • i.e.,*the*Swiss*DARPA*…* • website:*hTp://www.ar.admin.ch* • reference*person:*Dr.*Vincent*Lenders*

Common*aspects* • Rela'vely*“young”*projects* – OpenSky**500+*sensors* – Electrosense,*30+*sensors* – …*but*growing** • Open*data,*open*source*code* – all*data*provided*freely*for*research*purposes* – historic*data,*online*feeds*

Common*aspects* • Data]intensive*24/7*monitoring* – 10s*kB/sec/sensor*** – 10s]100s*GB/day* * • Centralized*archiving*and*processing* – server(s)*and*storage*hosted*&*maintained*by* armasuisse* 1*kB/sec/sensor**x*24*hours*=*0.86*GB/day/sensor***

Common*challenges* • Huge*volume*of*data*in*the*back]end** – data*streaming*technologies* – heavy*on*hardware,*solware*maintenance,*data*care** • Support*for*hosts/contributors* – Ini'al*sensor*shipment,*assistance*with*ini'al*setup,* troubleshoo'ng** • Other*specific*technical*challenges*discussed* later*…* *

Electrosense* Thanks*to*MaThias*Schaefer*and*Vincent*Lenders*

Background:*Primary*Surveillance* Radar% reflected*radio*signal*

Secondary*Surveillance*Radar*(SSR)* Transponder* interroga)on* message* broadcast*messages* 1090%MHz% 1030%MHz% (e.g.,*posi)on*reports)* reply*message* (in*response*to* interroga)on)* *

Secondary*Surveillance*Radar*(SSR)* broadcast*messages* 1090%MHz% (e.g.,*posi)on*reports)* reply*message* (in*response*to* interroga)on)* ModeNS* * Receiver*

Secondary*Surveillance*Radar*(SSR)* 1090%MHz% Internet% ModeNS* Receiver*

SSR,*Mode]S*and*ADS]B* SSR*messages* Mode]S* Mode]A* ADS]B* Mode]C* contain*GPS*posi)ons*

Mode]S*receivers* Radarcape*+*JetVision** ≈*700]800*EUR* …% Rasberri*Pi* ≈*35*EUR* RTL]SDR* ≈25*EUR*

Mode]S*receivers* Radarcape*+*JetVision** ≈*700]800*EUR* ≈*150]200*EUR*

Installa'on*in*Ljubljana*

flightradar24.com* Crowdsourced,*but*not*open*

opensky]network.org*

opensky]network.org*

example*of*recep'on*range*at*high*al'tude*

example*of*recep'on*range*at*high*al'tude*

example*of*recep'on*range*at*high*al'tude*

example*of*indoor*deployment*

OpenSky*Data*Inges'on*Layer*

Back]end*Architecture*

opensky*data** • Data*are*open* – ADS]B*data*accessible*via*online*API** – historical*accessible*via*online*query* – more*detailed*raw*(meta)data*available*on* request* • Code*is*open* – hTps://github.com/openskynetwork*

What*for?** • Ongoing*research*work*w/*opensky*data* – SSR*security*(e.g.,*spoofing*&*an']spoofing,* verifica'on,*fingerprin'ng)** – Spa'o/temporal*analysis*of*Air*Traffic** – Mul']latera'on,*posi'oning*algorithms* – Privacy]preserving*monitoring* – Es'ma'on*of*meteorological*parameters*(!)* – …*

Retrieving*Meteorological* Informa'on*From*OpenSky*Data* Ongoing*work*by*Dr.*Vincent*Lenders*

Mo'va'on* • Informa'on*about*upper*air* meteorological*condi'ons*is* important*for* – Avia'on*safety* – Weather*forcas'ng* • However,*only*sparse*sensing* capabili'es*today* – Weather%balloon :*only*sporadic* launches*at*few*sites*due*to*high* cost* – Windprofiler%/%Lidar :*limited* availability*and*range*(max.*8*km)* – Airplanes :*only*dedicated*aircral* are*equipped*(~600*aircral*in* Europe*[9])* 3 4*

Alterna've*Approach* • ATC*data*in*SSR*Mode*S*and*ADS]B*traffic*can*been* used*to*derive*meteorological*parameters*[1]* * * ! Temperature:*[4],*[5]* ! Wind:*[4],*[5]** ! Pressure* ! Turbulence:*[2]* [1]*Rui*Pinheiro,*Opensky*Workshop*2015** 35*

Open*Ques'ons* • Can*we*use*OpenSky*data*to*infer* – Temperature*?* – Wind*speed*?* – Wind*direc'on*?** – Pressure*?* – Turbulence*?* • What*is*the*expected*accuracy*?* • What*is*the*expected*coverage*?* • How*many*aircral*send*the*required*informa'on*?* 36* *

Technical*Challenges*w/*OpenSky*data* – ADS]B*doesn’t*provide*enough* informa'on*to*derive*useful* meteorological*parameters* – Mode*S*interroga'ons*are*directed* – Mode*S*replies*do*not*include* message*type* – Data*type*of*Mode*S*replies*must* be*inferred*based*on*format*and* context* – Decoding*of*Mode*S*replies* without*the*knowledge*of*the* corresponding*interroga'ons*

Es'ma'on*of*Meteorological* Parameters* 38*

Es'ma'on*of*Temperature*&*Pressure* Temperature% Pressure% International Standard Atmosphere (ISA) Pressure*at*zero* 101325*Pa* al'tude* Temperature*at*zero* Constant* c 288.15*K* al'tude* True*airspeed* Accelera'on*due*to* v t 9.80665*m/s 2* gravity* M Mach*number* ]6.5 { 10 ]3 *K/m * Lapse*rate* Gas*constant*for*air* 287.053*J/(kg*K)* References: [4], [5] References: [7], [8] 39*

Es'ma'on*of*Wind*Speed*&*Direc'on* Wind% ~ ~ v t v g ~ v w = ~ v g − ~ v t  � v g sin ↵ g − v t sin ↵ t ~ v w = v g cos ↵ g − v t cos ↵ t ~ v w True*airspeed* v t Heading* α t k ~ v w k Wind%Speed% v g Ground*speed* Track*angle* α g ∠ ( ~ v w ) Wind%DirecJon% References: [4], [5] 40*

Ongoing*Work* • Compare*to*reference*data** – Weather*balloon*data*from*MeteoSwiss* – Numerical*weather*model*from*MeteoSwiss* • Match*reference*data*to*es'mated*data*points** →*colloca'ons* – No*perfect*matches:*'me*difference*and*loca'on*distance* • Evaluated*components* – Comm]B*Decoder* – Preprocessing*filters* – Message*availability*world]wide*(3*con'nents)* – Es'ma'on*of*meteorological*parameters* 41*

Thanks*to*Roberto*Calvo*and*Domenico*Gius'niano*

Background:*the*radio*spectrum* • EM*waves*

Background:*the*radio*spectrum* • EM*spectrum*

Background:*the*radio*spectrum* • Radio*communica'ons*

Spectrum*Alloca'on*

Unlicensed*ISM*bands*(Europe)* 434%MHz% 868%MHz% 2.4%GHz% 5.4%GHz%

Mo'va'ons** • The*Electromagne'c*(EM)*spectrum*is*heavily*used* • Frequency* assignment *is*well*structured*and* defined.** • But*the*actual* usage *in*space/'me*is*unknown** • Today’s*spectrum*measurements*are*mainly* performed*by*a*few*governmental*agencies*with* expensive*specialized*hardware.** – limited*space/'me*sampling*density*

Mo'va'ons** • Goal*of*Electrosense:*crowdsourcing*spectrum* monitoring* using% commodity % low'cost' hardware* • Democra'ze*knowledge*of*radio*spectrum*usage* • Complements*other*monitoring*ini'a'ves* Microsol*Spectrum* DARPA*spectrum** Google*Spectrum*Database* Observatory* collabora'on*challenge**

Distributed*monitoring,** Centralized*Archiving*

Applica'ons*

Electrosense*sensors*evolu'on* Single]board*computer*(RPi)*+* RF*front]end*(RTL]SDR*USB)*for*signal*acquisi'on* RPi]2,*new*version*of*RTL]SDR* *+*GPS*device*for*'ming*synchroniza'on* Frequency]range* extension* 2]3.6*GHz** and*5]6*GHz* …*

Commodity*Low]cost*Hardware** is*evolving*

Monitoring*single*band* Acquisi'on** Fmax=1.8/3.6*GHz** Bandwidth*2.2*MHz** Fmin*=*20*MHz* Frequency* Time*

Sweeping*the*frequency*range* Acquisi'on** Bandwidth*2.2*MHz** Fmin*=*20*MHz* Fmax=1.8*GHz** Frequency* Time*