A method is presented for estimation of the frequency

azimuth and elevation angles of the signal over a very wide frequency band (2~18GHz) with sub-Nyquist spatio-temporal sampling.Using a uniform circular array and antennas time-delaying

it can provide unambiguous frequency estimation under temporal undersampling

and provides unambiguous azimuth and elevation estimation using integer search algorithm under spatial undersampling.The estimations of azimuth and elevation and corresponding frequency are automatically paired.It not noly can use second-order statistics in element space or DFT beamspace

but also can use fourth-order cumulants to estimate the parameters of non-Gaussian sources in Gaussian white or colored noises.The variance of the azimuth and elevation estimates of this method is 1~2 orders less than that of L-shaped array algorithm under the same antenna numbers and the maximum aperture in DFT beamspace.Simulations are presented to show the capabilities of the algorithm.