High-directional beamforming with a miniature loudspeaker array

Practical electroacoustic applications often demand a directional behavior of the dedicated loudspeaker setup. A common goal in sound reproduction applications is a uniform distribution of sound pressure over the listening area. A desired application in sound reinforcement is to focus the emitted sound to a defined region, to locally enhance speech intelligibility in reverberant environments or to keep high sound pressure levels on certain areas. The use of loudspeaker arrays with dedicated signal processing is a well-known technique to create directional radiation characteristics. This technology, often termed as loudspeaker beamforming, allows controlling the radiation of sound to a distinct direction. For decades directional sound radiation is used in public address systems. In recent years similar requests came up for other markets like home entertainment. Due to the size of conventional speaker systems, the usage in this field is still not feasible. This paper presents the design of a miniature beamforming array. The presented concept shows an array that consists of a small number of loudspeakers, while providing a high directional radiation behavior.