Abstract: A method for the compensation of frequency-response mismatch errors in M-channel time-interleaved ADCs. The compensation is done utilizing a technique that makes use of a number of fixed filters, that approximate differentiators of different orders, and a few variable multipliers that directly correspond to parameters in polynomial models of the M channel frequency responses. A compensated M-channel time-interleaved ADC is based on and can perform the method.

Abstract: Method and apparatus for positioning a coupling means in a gearbox in a first gear position, a second gear position and an intermediate neutral position. The apparatus includes a housing (5) that forms a working cylinder (6), a main piston (7) arranged in the working cylinder (6) in order to interact operationally therewith, and a piston rod (8) connected rigidly to the main piston and extending from a first side thereof out of the housing (5). The piston rod (8) is connected to the coupling means or mechanism (4) outside the housing. The main piston (7) is arranged displaceably between three different positions in the working cylinder that correspond to the first and second gear positions, and the neutral position. An auxiliary piston (11) is also arranged displaceably inside the housing. The auxiliary piston (11) is adapted to operationally interact with the working cylinder and is arranged on a second, opposite side of the main piston relative to the first side.