Low Probability of Intercept (LPI) radars are a special class of radars designed not only for outstanding target detection performance but also to remain unseen and unknown by means of passive intercept receivers, that listens for emitter signals in the surrounding atmosphere and identifies the transmitting sensor.
To remain unseen, the LPI radar reduces its transmitted output power level and makes use of the wide radio frequency (RF) bandwidth available. To stay unknown, LPI radars also apply less predictable transmit patterns and waveforms. To handle the instantaneously wide range of signal spectra, electronic surveillance (ES) systems are designed for wide system bandwidth, high sensitivity and high signal dynamics. To enable detection of the “invisible” LPI waveforms from the interfering background signal, ES systems must apply advanced signal processing techniques. The “signal battle” between radars and ES systems has been ongoing for decades and will more rapidly evolve at both sides of the battle due to the technology trend towards more digitized systems in combination with the use of active electronically scanned array (AESA) antennas. The former analogue technology restrictions are currently been replaced by digital system solutions enabling more flexible design and massive use of new techniques and tactics for LPI radars and ES systems. SAAB develops radars and ES systems based on the AESA technology for land, airborne and maritime applications. The SAAB systems are integrated on a wide range of platforms including fighter aircrafts, airborne surveillance planes, military ships, submarines and land vehicles.
This project shall study novel techniques and tactics for wideband AESA radars improving their low probability of intercept characteristic.
The project shall include the study and development of wideband waveforms that in combination with intra-pulse modulation, waveform diversity and asymmetrical beamforming and beam steering makes the detection, recognition and classification of the radar signals more challenging for the passive intercept receiver.
Developed techniques are implemented and evaluated in an existing Matlab model of an general wideband AESA radar.
The main tasks of the project are:
- Conducting literature survey on the key technologies
- Study/develop LPI technologies based on:
- Wideband LPI waveforms
-Intra-pulse modulation and waveform diversity
- Array antenna beamforming and beam steering
- Techniques and tactics implementation and evaluation in general AESA Matlab model
- Writing of your Master’s thesis including a summary of conclusions and recommendations for future work
- Presentation of your Master’s thesis
- Successfully completed (or nearly finished) university level studies in Degree of Science in Engineering towards Engineering Physics, Electrical Engineering or Computer Engineering
- Good skills of Digital Signal Processing
- Good skills in programming (Matlab)
- Basic skills in programming (C/C++, JAVA similar)
- Understanding of RF receiver/transmitter architectures
- Basic skills in Microwave Engineering
- Practical RF measurement experience
- Experience working in a lab environment
- Experience in leadership
This position require that you will be approved in a security screening in accordance with the Swedish Protective Security Act.
Your workplace will be at the Business Area Surveillance located in Stockholm Järfälla. The BA Surveillance provides efficient solutions for safety and security, for surveillance and decision support, and for threat detection and protection.
The portfolio covers:
-Airborne, ground-based and naval radar
-Electronic warfare, combat systems and C4I solutions
This project is performed at the department Sensor Systems, which is a part of the Product Area Electronic Surveillance. At Sensor Systems we develop:
-Radar systems for target seeker and fire control applications.
-Electronic surveillance systems for ground-based, naval and airborne