In this paper, a new super-resolution and highly stable DOA estimation technique of coherent sources is introduced. Furthermore, the proposed technique is applied to the data collected from the AWR1243 mm-wave 76-81 GHz frequency modulated continuous wave (FMCW) radar to estimate the DOAs of real targets. A virtual antenna array is proposed to increase the array aperture size and the dimension of the data covariance matrix which effectively helps in de-correlating the received signals and in increasing the number of detectable sources and hence improving the detection resolution. Moreover, a significant improvement in the DOA estimation capability is achieved by handling the frequency domain of the received signals instead of their time-domain representations. That is because the signal to noise ratio (SNR) is increased by a multiplication factor when it is transformed using FFT which acts as a filter for the noise. The simulation results proved the superiority of the proposed technique compared to the state of the arts in this field, especially at low SNR that approaches -35 dB.
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