Mahmut Serin

FPGA-based match filter implementation in frequency domain using an overlap-add method

In this research, a real time matched filter is implemented on FPGA using an overlap-add method. The matched filter that increases the signal-to-noise ratio (SNR) for pulse compression and low probability intercept (LPI) radars is implemented in digital domain. This design is implemented on Xilinx Virtex-5 based processing board that samples in intermediate frequency (2.5 GHz). In the overlap-add method, we propose to design the matched filter by using two parallel FFT cores. Furthermore, the matched filter results are presented for different intra-pulse modulations.

Real-time frequency parameter extraction for electronic support systems

In this research, real time automatic frequency parameter extraction methods for electronic support systems are implemented on FPGA. The frequency parameter is extracted by using digital instantaneous frequency measurement (DIFM) and fast fourier transform (FFT) methods. Estimation performances of these two different methods for different type of radars at different signal to noise ratios (SNR) are analyzed. This design is implemented on Xilinx Virtex-6 based processing board that samples in 2.5 GHz. Experimental results of the design for FPGA implementation are presented.

Real time wideband direction finding

In this paper, the developed FFT based interferometric direction finding of wideband radar threats for electronic support (ES) and electronic intelligence (ELINT) is presented. Using this method, target radar signal is separated from other radar signals using FFT. Phases of extracted radar signals for two or more channels are calculated. Angle of arrival of extracted radar signal is estimated with the phase differences of each channel pair at selected radar frequency. This method is also applied to frequency agile radars and pulse compression waveform radars. This method is implemented on FPGA platform in real time. For different SNR values, FFT sizes, radar signal instantaneous bandwidths simulation results and real time implementations are presented.

Implementation of Doppler noise jamming techniques using DRFM

In this paper, hardware implementation of Doppler noise and narrow band Doppler noise techniques those are jamming of Doppler frequency based on FPGA is explained. Pulse Doppler radar signal generator and receiver parts and algorithms of techniques are implemented on the Xilinx Virtex-4 FPGA. Besides, effective jamming to signal ratios of Doppler noise and narrow band Doppler noise techniques are compared.

Implementation of digital pulse doppler radar signal generator and receiver

In this paper, hardware implementation of digital pulse Doppler radar signals generator and receiver based on FPGA is explained. Different performances have been noticed while using CORDIC and Hilbert transform cores for the phase shifter blocks in the implementation of generator and receiver parts. Algorithms are implemented on the Xilinx Virtex-4 FPGA. Required hardware area, resolution and amplitude of Doppler frequency at the output of the receiver are compared for different implementation with altering the phase shifter block.

A comparison on the new electronic attack techniques against pulse compression radars

In this study, the mathematical models of Smeared and Chopping/Interleaving Spectrum techniques, which are recent electronic attack techniques against the pulse compression radars, are presented. Then, matched filter outputs are compared by means of a simulator. Moreover, the effect of the weighting filter in the radar receiver is also analyzed.

Multitab digital instantaneous frequency measurement receiver

This paper proposes an instantaneous frequency measurement (IFM) receiver structure for electronic support measure (ESM) systems. The performance of instantaneous frequency (IF) measurement improves as the IFM receiver delay increases. However, it is observed that the increasing delay introduces ambiguity to the IF measurement In order to resolve the ambiguity, an algorithm which uses the IFM receiver blocks of different delays in parallel is proposed. The IF measurement performance of the proposed IFM receiver is analyzed for different modulation types, pulse widths and signal to noise ratios.

Real-time instantaneous radar frequency measurement for pulse on pulse condition

In this research, a method which is implemented on FPGA for real-time extraction of the instantaneous frequency parameters of two simultaneous radar pulses (POP) in electronic support systems is presented. The frequency parameters of two different radars overlapped on time are extracted separately by using digital instantaneous frequency measurement (DIFM) method. Estimation performances of this method for different type of radars at different signal to noise ratios (SNR) are analyzed. This design is implemented on Xilinx Virtex-7 based processing board. Experimental results of the design for FPGA implementation are presented.

Real time Kalman filter implementation on FPGA environment

In this paper, implementation of real-time Kalman Filter on FPGA is presented. In the design, sequential Kalman Filter is selected that uses division under specific assumptions instead of using the inverse of the matrices intensively as in the Kalman Filter. This design can also be used in radar target tracking systems working on coastline that has crowded traffic. By comparing computer and FPGA results in the simulation platform, this design is verified.

Real time passive direction finding in FPGA environment

In this paper, FGPA implementations of amplitude and phase comparison direction finding methods are presented. In amplitude comparison direction finding (AC-DF), the power ratio between the receiver channels is compared with the values in the look-up-table that is generated using antenna patterns. In phase comprison direction finding (FC-DF), basically the phase difference is extracted between channels of the receiver and the angle of the arrival is estimated using the distance between the receiver antennas and wavelength of the received signal. In this paper, real time DF is enabled at the end of pulse duration. For various signal to noise ratio and the angle of arrivals, detailed analysis are experimented to measure the real time performances.