Frequency-invariant beam steering based on FIR-filters




beamforming, antenna array, FIR-filter, frequency-invariant method, beam steering


Conventional narrowband beamforming methods are not effective for wideband antenna arrays. Radiation pattern of such array has various beam width over the frequency. Existing frequency-invariant beamforming methods using finite impulse response filters (FIR-filters) can solve this problem. FIR-filters provide frequency response required for frequency-independent properties of the array radiation pattern but their common feature is a high computational complexity. In this paper, we present the fixed frequency-invariant beamforming method that does not require minimizing functions or the Fourier transform. The beam steering is achieved by using FIR-filters with different slope of the frequency response. The proposed approach is based on the FIR-filters synthesis with special frequency characteristics. The numerical results compared with the existing frequency-invariant beamforming method are shown.


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