Conference Papers
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506
Browse
Search Results
Item A Conceptual Framework for Knowledge Aided Passive Radar System(Institute of Electrical and Electronics Engineers Inc., 2021) Lingadevaru, P.; Srihari, P.; Pardhasaradhi, B.; Gunnery, S.Significant recent radar research has been focused on knowledge aided signal processing, waveform design, detection and target tracking applications. Passive radars have the edge over active radars in spectrum utilization and covert operation for target detection and tracking applications. Passive radars generally use the existing illuminators of opportunity to detect or track the targets. The knowledge pertaining to illuminator of opportunity (IOO) selection, spectrum sensing, and diversity technique can predominantly improve the received signal strength (RSS) at the passive radar receiver. This paper proposes a Conceptual framework to build a Knowledge Aided Passive Radar System (KA-PRS) based on spectrum sensing, IOO selection, and spatial diversity. The mathematical modelling and functional blocks to build the KA - PRS are discussed. The analytical and simulation results reveal that KA-PRS provides improved signal-to-noise (SNR) ratio compared with the traditional passive radar. © 2021 IEEE.Item Nonlinear Frequency Modulated Waveform Optimization for a Cooperative Radar-Communication System(Institute of Electrical and Electronics Engineers Inc., 2021) Mahipathi, A.C.; Gunnery, S.; Srihari, P.; D'Souza, J.; Jena, P.Co-existence research related to radar and communication systems has gained significant interest in the last decade to address the spectrum scarcity issues. Designing an optimal waveform for a Joint Radar-Communication (JRC) system is an important consideration to practically realize the convergence of these two subsystems. This paper proposes a Power Ratio Constraint (PRC) based optimization technique to evaluate phase coefficients of Non Linear Frequency Modulated (NLFM) waveform for a Cooperative Radar-Communication System (CRCS). The radar waveform is optimized here using the Cramér-Rao Lower Bound (CRLB) metric in conjunction with the PRC. We investigated the spectral energy distribution, auto correlation function, and estimation rate for radar systems using optimized NLFM waveform phase coefficients. In addition, data rate for communication system is computed. Further, the simulation results shows that, proposed joint PRC-CRLB based optimization method confines the radar spectrum, reduces the delay ambiguities and enhances the information rate of CRCS. © 2021 IEEE.Item Quantized Directional Cosine measurements based Localization(Institute of Electrical and Electronics Engineers Inc., 2021) Reddy, B.B.N.; Gunnery, S.; Pardhasaradhi, B.; Srihari, P.Localization of target emitters using multiple simultaneous directional cosine (DC) measurements are popular and extremely useful in radar and sonar surveillance systems. Underwater localization, classification, and target tracking using hydrophone with limited bandwidth constraints is a challenging problem. In limited bandwidth applications, quantizing the measurements is an efficient way of representing measurements. The DC measurements are usually in the range of -1 to +1, the quantization of DC leads to inaccuracy in the estimated values. This paper presents the localization problem with quantized DC measurements in densely populated targets scenario. The localization achieved using two different estimation techniques: the least-squares (LS) triangulation and the Quasi newton (QN) method. Further, to explicitly study the quantization effect, we have used linear and optimal quantization techniques to quantize the DC measurements. The performance of the localization is quantified using the position root mean square error (PRMSE). © 2021 IEEE.Item Target Estimation Performance Improvement in Cooperative Radar and Communication system Spectrum Sharing(Institute of Electrical and Electronics Engineers Inc., 2021) Gunnery, S.; Pardhasaradhi, B.; Prashantha Kumar, H.; Srihari, P.This paper presents target estimation performance improvement in cooperative radar and communication system spectrum sharing system model. Due to cooperation, target returns results from the communication transmitter are also exploited to improve the target estimation performance. Further, Cramer-Rao Lower Bound (CRLB) is considered as a metric to evaluate the target estimation performance. In addition, the effect of transmitting energy and target reflection coefficient on CRLB is analyzed. The cooperative system model is compared with the non-cooperative radar and communication system spectrum sharing operation and stand-alone radar system operation. Results show that the cooperative radar and communication system spectrum sharing system model provides improved performance compared to non-cooperative and stand-alone operations. © 2021 IEEE.