| 摘要 |
<p>A tracking filter (10,80) which transitions from a type 2 loop to a type 1 loop as the loop error approaches 0 for fast settling and convergence without overshoot or ringing. The filter can either be implemented as an analog circuit (10) in hardware or digitally (80) in software. A first integrator (30) or first accumulator (82) is utilized to increment or decrement a discriminator (22,96) output error value as long as the sign of its output (32) from the previous iteration is the same as a sign of the error signal provided to its input (26) by the error discriminator (22,96). The first integrator output is limited to a range by a limiter (42) between a minimum and maximum value. If the sign of the first integrator output is different from the sign of the input, the contents of the first integrator or accumulator are dumped. The output from the first integrator or first accumulator has binary scaling (44,94) to scale its value before adding it to a second integrator (50) or second accumulator (88). <IMAGE></p> |
