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Passive Coherent Location (PCL), eller Passiv Radar som det populärt kallas, är enteknologi inom radarlära som innefattar radartyper som inte själva skickar ut elektromagnetiska vågor för att finna och undersöka ett mål. Istället använder sig dessa radartyper av befintliga signaler, såsom radio- och TV-sändningar för att detektera mål. På så vis är det betydligt svårare att upptäcka en passiv radar jämfört med en traditionell aktiv radar. SAAB utvecklar teknologi och metoder för passiva radarsystem. För att få en förståelse för ett av deras PCL-systems prestanda behöver SAAB utveckla en enkel metod för att fastställa radartäckningen. Som ett steg till detta har SAAB därför givit författaren till denna rapport i uppgift att skapa ett gränssnitt som kombinerar och jämför PCL-systemet med detektioner från en automatic dependent surveillance broadcast (ADS-B). Detektionerna från ADS-B kan då fungera som ett facit för hur väl PCLsystemet tar upp detektioner. Vilket ger gränssnittets användare en god indikationför PCL-systemets utsträckning och reliabilitet. Intervjuer hölls med anställda på SAAB som har erfarenhet av att arbeta med likvärdiga system och dess gränssnitt. Intervjuerna var semistrukturerade med frågor som syftade att utforska vilka funktioner som uppskattas och vilka svårigheter deltagarna ser i nuvarande gränssnitt. Utefter deltagarnas svar på intervjuerna byggdes en behovsanalys som tillsammans med teorier inom området låg till grund för utformningen av gränssnittsprototypen. Lösningsförslaget är en gränssnittsprotyp som visar datapunkter där detektion av mål visas från PCL-systemet och ADS-B. / Passive Coherent Location (PCL), or more popularly known as Passive Radar, is a subgenre within the field of radartechnology which includes radar types that does not transmit electromagnetic signals by themselves to find and investigate targets. Instead, they use already existing transmission, such as radio and TV broadcasts, to detect a target. Thus, it is much harder to discover a passive radar compared to a traditional active radar. SAAB is developing technologies and methods for passive radar systems. To get an understanding of the performance of one of their PCL systems, SAAB is looking for a simple method to determine the coverage of the radar. As part of this SAAB has given the author of this report the task of developing an interface which combines and compares the PCL-system with the detections of an automatic dependent surveillance broadcast (ADS-B). The detections from the ADS-B can then act as an answer key for how well the PCL-system detects targets. Thus, giving the interfaces user a good indication for the PCL-systems coverage and reliability. Interviews were conducted with SAAB employees experienced in working with similar systems and their interfaces. These interviews were semi-structured, with questions aiming to explore appreciated features and identified challenges in the current interfaces. A needs analysis was constructed based on the participants answers in the interviews, which, combined with theories within the field served as the foundation for designing the interface prototype. The proposed solution is an interface prototype, displaying data points from the PCL system and ADS-B.

<p>In this thesis the problem of multitarget tracking in multistatic sensor networks is studied. This thesis focuses on tracking airborne targets by utilizing transmitters of opportunity in the surveillance region. Passive Coherent Location (PCL) system, which uses existing commercial signals (e.g., FM broadcast, digital TV) as the illuminators of opportunity for target tracking, is an emerging technology in air defence systems. PCL systems have many advantages over conventional radar systems such as low cost, covert operation and low vulnerability to electronic counter measures.</p> <p>One of another opportunistic signals available in the surveillance region is multipath signal. In this thesis, the multipath target return signals from distinct propagation modes that are resolvable by the receiver are exploited. When resolved multipath returns are not utilized within the tracker, i.e., discarded as clutter, potential information conveyed by the multipath detections of the same target is wasted. In this case, spurious tracks are formed using target-originated multipath measurements, but with an incorrect propagation mode assumption. Integrating multipath information into the tracker (and not discarding it) can help improve the accuracy of tracking and reduce the number of false tracks.</p> <p>In this thesis, these opportunistic measurements, i.e., commercial broadcast signals measurements in PCL tracking and resolvable multipath target return measurements in multipath assisted tracking are exploited. We give the optimal formulations for all of the above problems as well as the performance evaluations using PCRLB. Simulation results illustrate the performance of the algorithms.</p> / Doctor of Philosophy (PhD)