Progress of roles and schemes of calibration techniques in data converters are reviewed. Correction techniques of matching error and nonlinearity in analog circuits have been developed by digital assist using high-density and low-power digital circuits. The roles of the calibration are not only to improve accuracy but also to reduce power dissipation and chip area. Among various calibration sch...

This paper presents an improved iterative nonlinear calibration method in the gravitational field for both low-grade and high-grade triaxial accelerometers. This calibration method assumes the probability density function of a Gaussian distribution for the raw outputs of triaxial accelerometers. A nonlinear criterion function is derived as the maximum likelihood estimation for the calibration p...

The growing market for location-based services causes a great demand for positioning systems with high accuracy. In addition to GPS, there are several WiFi positioning systems which allow a cost-effective indoor and outdoor positioning. But despite the fact that they provide accurate measurements in indoor environments, their outdoor performance is not as good as with GPS. This is due to the fa...

A simple method which does not require calibration with a reference liquid for the determination of attenuation and density of a fluid contained within a thin-walled cell is demonstrated. The method relies on temporally filtering the impulse response of the system to partially deconvolve the transfer function associated with the wall. Experiments are conducted on cells of differing material con...

This paper describes a novel three-dimensional sound intensity probe consisting of 8 MEMS (micro-electromechanical systems) microphones and a novel free-field calibration method. The use of MEMS-microphones allows for a very compact design compared to probes that employ 1/2-inch condenser microphones. A novel free-field calibration method, based on the principle of microphone interchange, is de...