| 摘要 |
An adaptive control system for reducing undesired signals comprises sensors (31) to provide signals indicative of the undesired signals, and a processor (36) which processes the first signal to provide a secondary signal for output to sources (37) to interfere with the undesired signals. Sensors (42) are provided to detect the residual signals which are indicative of the interference between the undesired and secondary signals. Within the processor the signals indicative of the undesired signals and the residual signals are transformed into the frequency domain and collated. The outcome of the collation is inverse transformed and the processor adjusts the secondary signal using this inverse transform to reduce the residual signal from the sensors (42). |
