Subspace based radar signal processing methods for array tapering and sidelobe blanking

Dinler, Doğancan
The discretization of the signal impinging on several hundreds, even thousands, of receiving elements has become a common problem in modern phased array radar systems along with the developments in the digital signal processing. The spatial and temporal processing of such large dimensional data is too challenging for all steps of signal processing. This thesis is focused on the subspace methods that making the processing of the full dimensional data feasible at reduced dimensions. The first objective of the thesis is to develop a proper subspace such that the essence of the signal coming from a predefined sector is captured at reduced dimensions. To realize that aim, eigenvector and Fourier bases of the sector are studied and evaluation of these bases are performed considering the detection and parameter estimation performances. The second objective is to apply some conventional radar signal processing methods, namely array tapering and sidelobe blanking, at reduced dimensions. The main contributions are subspace construction and reduced dimensional implementations of array tapering and sidelobe blanking. Numerical results are provided to evaluate the performance of suggested methods in different scenarios. 


Performance analysis of direction-of-arrival estimation algorithms in the presence of array imperfections and multipath for different antenna array geometries /
Çalışkan, Mustafa; Tuncer, Temel Engin; Department of Electrical and Electronics Engineering (2014)
Direction of Arrival (DOA) Estimation is an important topic in signal processing. In this thesis, DOA estimation is considered when there are gain/phase mismatches, mutual coupling for the antennas and multipath signals are observed. In the first part, DOA estimation for uniform linear array (ULA) in the presence of mutual coupling is considered. Different methods in the literature are investigated and a promising solution for this case [1] is implemented. Auxiliary sensors are used and MUSIC algorithm is e...
Phased array antenna calibration and experimental validation
Yalım, Alper; Demir, Şimşek; Department of Electrical and Electronics Engineering (2013)
In this thesis, nine different methods aiming calibration of Phased Array Antenna (PAA) and Multifunctional Radars which employ PAA are presented. Those calibration methods are described, procedures of the methods are explained in detail, and information about constraints and measurement restrictions of those methods is given. As one step further, comprehensive work is focused on Multi-Element Phase Toggling (MEP) method and Rotating Element Vector (REV) method. Results of simulations are shown, theoretical...
Dimension reduced robust beamforming for towed arrays
Topçu, Emre; Candan, Çağatay; Department of Electrical and Electronics Engineering (2015)
Adaptive beamforming methods are used to obtain higher signal to interference plus noise ratio at the array output. However, these methods are very sensitive to steering vector and covariance matrix estimation errors. To overcome this issue, robust methods are usually employed. On the other hand, implementation of these robust methods can be computationally expensive for arrays with large number of sensors. Reduced dimension techniques aim to lower the computational load of adaptive beamforming algorithms w...
Development of beam scheduling algorithm for frequency diverse array /
Çetiner, Ramazan; Demir, Şimşek; Department of Electrical and Electronics Engineering (2015)
Electronic scanning is the most desirable feature of radar systems. With electronic scanning, it is possible to steer the main beam of an array antenna instantaneously into a desired direction where no mechanical mechanism is involved in the scanning process. Electronic scanning methods including phase scanning, time delay scanning, and frequency scanning have been used in various radar applications; however new and cheaper scanning methods are still being investigated. It is the purpose of this thesis to i...
Wideband omnidirectional and sector coverage antenna arrays for base stations
Alatan, Lale (2018-01-01)
By using parallel strip line fed printed dipole antennas as array elements, an omnidirectional antenna array and a wide angle sector coverage array operating in octave band are designed. A maximum deviation of ±1.25 dB from the omnidirectional pattern is achieved for the omnidirectional array, and the average gain of the antenna was measured as being 5 dB in the 1.35–2.7GHz band. For the sector coverage array, a special reflector design is utilized to maintain a half power beam width of around 115◦ with a s...
Citation Formats
D. Dinler, “Subspace based radar signal processing methods for array tapering and sidelobe blanking,” M.S. - Master of Science, Middle East Technical University, 2017.