摘要 |
<p>A signal processor receives random input signals from a pair of sensors such as beam sensing electrodes, antennas, microphones or optical position sensors. An estimation equation implemented by the signal processor uses weighted integration of log ratios where the weighting is adaptive and depends upon the values of signal samples being processed. The signal processor uses digital signal processing to provide an estimate of the desired parameter. Nonlinear functions such as hyperbolic tangent and logarithm are contained in programmable read only memories in order to obtain high speed operation. When the signal processor is used in conjunction with channel switching, errors due to channel mismatch are completely eliminated. In a preferred embodiment, the sensors are beam sensing electrodes and the signal processor is used for estimating the position of a scanned ion beam in a ion implantation system.</p> |