Patent ID: 8521802

Claim:
An arbitrary power law function generator, comprising a series cascade having n logarithmic function blocks feeding a series cascade of n exponential function blocks, n being a user selectable number of the function blocks, wherein: each of the exponential function blocks has a current-controlled exponential function-generating electronic transistor circuit having a first current input, a first current mirror, and a first current output, the circuit having a first transfer function relating the first current output to the first current input according to an equation characterized by the relation: I o = I o ⁢ ⁢ 1 - I o ⁢ ⁢ 2 = I D I A ⁢ ( I B ⁢ ⁢ 2 - I B ⁢ ⁢ 1 ) ⁢ exp ⁡ ( I in ⁢ R V T ) , where the first output current, I o =I o1 -I o2 , I A , I B1 , I B2 and I D are control currents adjusting gain and polarity of the exponential function, and R is an input resistance feeding the first current mirror; and each of the logarithmic function blocks has a current-controlled logarithmic function-generating electronic transistor circuit having a second current input, a second current mirror, and a second current output, the circuit having a second transfer function relating the second current output to the second current input according to an equation characterized by the relation; I o ′ = I o ⁢ ⁢ 1 ′ - I o ⁢ ⁢ 2 ′ = V T ′ R L ′ ⁢ ln ⁡ ( I in ′ I ref ′ ) , where the second output current I′ o =I′ o1 -I′ o2 , represents the output current, I′ ref represents a control current, and R′ L is a logarithmic function gain control resistance.