Patent ID: 6907441

Claim:
A control system comprising: a linear controller that outputs a first signal; a first multiplier having a first input coupled to receive the first signal; a first summer having a first input coupled to an output of the first multiplier; a scaler having an input coupled to an output of the first summer; a first delay having an input coupled to an output of the scaler and an output coupled to a second input of the first summer, the output of the first delay providing a second signal that is a square root of the first signal; a second multiplier having a first input coupled to the output of the first delay; a second summer having a first input coupled to an output of the second multiplier and a second input coupled to a constant; a third multiplier having a first input coupled to an output of the second summer and an output coupled to a second input of the first multiplier; a second delay having an input coupled to an output of the third multiplier and having an output coupled to second inputs of the second and third multipliers; and, a non-linear instrument coupled to receive the second signal, wherein the second signal is a pre-distorted form of the first signal such that the non-linear instrument provides a linear output with respect to the first signal.