Local oscillator parameter estimation of collaborative beamforming nodes

Abstract

Parameter estimation of complex exponential signals corrupted by additive white Gaussian noise (AWGN) is crucial in the study of distributed beamforming in a practical scenario. Near zero (0) phase offset are expected at the receiver end which rely on the smoothing and correction of the frequency and phase estimates. Neither computational complexity nor the processing latency has an effect on the expected zero phase offset but the estimation accuracy does. Thus, the maximum likelihood estimator (MLE) using Fast Fourier Transform (FFT) approach is being considered for cases with none and post processing in locating of the maximum peaks. Details on how the phase estimates are arrived at is not always covered in literatures but explained in the article. Numerical results obtained showed that global maximum peaks are arrived at by employing a fine search with higher values of FFT.