Directional Emphasis in Ambisonics

We describe an ambisonics enhancement method that increases the signal strength in specified directions at a low-computational cost. The method can be used in a static setup to emphasize the signal arriving from a particular direction or set of directions. It can also be used in an adaptive arrangement where it sharpens directionality and reduces the distortion in timbre associated with low-degree ambisonics representations. The emphasis operator has a very low-computational complexity and can be applied to time domain as well as time–frequency ambisonics representations. The operator upscales a low-degree ambisonics representation to a higher degree representation.

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