The results show that the smart antenna can efficiently strengthen useful signal, decrease interference and form the optimum directivity diagram.
结果表明，智能天线可以有效增强有用信号，降低干扰，从而形成最优的方向图。
2
Audio directional loudspeaker is a novel loudspeaker which can generate an audio signal with high directivity by utilizing the parametric array principle.
声频定向扬声器是利用参量阵原理，产生高指向性声频信号的新一代扬声器。
3
Acoustic vector sensor with the electronic rotating directivity of dipole can effectively detect signal in the background of noises. More information can certainly be obtained by vector sensor array.