Application of nonlinear compensation to limit input dynamic range in analog optical fiber links

Abstract

The dynamic range of a signal at the input of a measurement system during a short circuit test is increased several times by the nominal input voltage. Saturation of the measurement system may occur in a device under failure test. This paper introduces the application of a nonlinear compensation to limit the voltage range at the input of a voltage controlled oscillator which is used to produce the pulsed frequency modulation needed to transmit the analog signals over the optical fiber links. The proposed dynamic range compensation system is based on non-linear circuits to accommodate the input range of the voltage controlled oscillator. This approach increases the transient signal handling capabilities of the measuring system. This work demonstrates that the nonlinear compensated optical fiber approach yields a unique, electrically isolated, lightning-proof analog data transmission system for remote measuring systems in the highly aggressive EMI environment of high-power test laboratories.