The present project focuses on scientific issues related to new application of GPS in radar networks using the effect of Forward Scattering (FS) of electromagnetic waves to detect, locate and classify objects by their GPS radio shadows. The project theme is new for Bulgaria, combining the processing of GPS signals and processing of radar signals.

The idea is to use the information available from the radio shadow (length, depth, and spectrum) in order to enhance the performance of the algorithms in conventional GPS receivers.

The aim of the project is to make experimental studies of GPS radio shadows of different objects irradiated by GPS signals and to develop methods and algorithms for automatic detection, estimation and classification of the shadows of these objects, and also to check ability to use the same technology in case of audio shadows.

The scientific hypothesis is that radio and audio shadows contain valuable information about the objects that can be used to improve the performance of systems with secondary application of wireless technologies. These are FS passive bistatic positioning systems based on radio communication or radio navigation systems, in particular the GPS system. Normally in conditions of radio shadow of the subject these passive radio systems lose the object. When the object is close to the line between the transmitter and the receiver, the receiver loses the reradiated signal from the object (radio shadow). When the user of the GPS information moves in urban, he kept losing signal because of tall buildings or trees, bridges, etc.. Because it falls in the shadow of buildings.

The practical utility of the proposed idea is to use a specific processing of the received signal in the GPS receiver, then the extracted information can be used for positioning and classification of moving objects; for accurate assessment of the geographic location of fixed objects by method triangulation in systems for transport management; security of zones; for subsequent identification of the detected objects with these from digital geographical maps, and the like.


GPS, FS radar, radio and audio shadow, detection, estimation, classification