| 摘要 |
<p>The device can be used particularly for recognising the presence of an audio-frequency programme signal in an input signal. In the device, the input signal is sampled and the samples are subjected to amplitude analysis during successive time intervals of predetermined duration which is long enough for the distribution gathered to be representative of the distribution of amplitudes obtained for several successive intervals in the input signal. The amplitude distributions are compared in order to identify the presence of the programme on the basis of stochastic properties of the programme signal. This process can be implemented in a device incorporating a sampling means, a multi-channel analyser (30) and a computer means (36). <IMAGE></p> |
