Sound Reproduction with a Circular Loudspeaker Array Using Differential Beamforming Method

This paper proposes an approach to get frequency invariant, symmetric beampattern using a compact circular loudspeaker array. The Jacobi-Anger expansion method is used to approximate the target beampattern. The simulated performance is compared of the same circular loudspeaker array with and without a rigid baffle. The analytical solution of the weight and the simulation results show that the circular loudspeaker array with a rigid baffle can overcome the null problem confronting the array without a rigid baffle. The minimum-norm filter is used to improve the robustness of the system and maintain the frequency-invariant beampattern over the frequency range of interest.