Abstract: A method is suggested for robust estimation of a subset of carrier phase integer ambiguities for precise ionospheric delay estimation. The advantages of this method are the precise estimation of receiver and satellite biases, an increase in the number of reliably fixable ambiguities, and an improved accuracy for the ionospheric delay estimation.

Abstract: A new method for bias estimation on multiple frequencies with a Kalman filter is proposed. It consists of four steps: First, a least-squares estimation of ranges, ionospheric delays, ambiguities, receiver phase biases and satellite phase biases is performed. The code biases are absorbed in the ranges and ionospheric delays, and a subset of ambiguities is mapped to the phase biases to remove linear dependencies between the unknown parameters. In a second step, the accuracy of the bias estimates is efficiently improved by a Kalman filter. The real-valued a posteriori ambiguity estimates are decorrelated by an integer ambiguity transformation to reduce the time of ambiguity resolution. Once the float ambiguities have sufficiently converged, they are fixed sequentially in a third step. Finally, a second Kalman filter is used to separate the receiver and satellite code biases and the tropospheric delays from the ranges.

Abstract: The present invention provides a fuselage structure for an aircraft or spacecraft with an outer skin. The fuselage structure comprises a rib element for stiffening the outer skin and ad cross member element. Here the rib element is bent in the shape of an arc to correspond to an inner contour of the outer skin. The cross member element connects two arc sections of the rib element transversely to each other. The cross member element has a higher strength than the rib element. From another point of view the invention provides an aircraft with such a fuselage structure.

Abstract: A method for estimating satellite-satellite single difference biases is described. The method uses an ionosphere-free mixed code-carrier combination of maximum ambiguities discrimination defined at the ration between wavelength and noise standard deviation. The accuracy of the biases estimation is further improved by an additional ionosphere-free mixed code-carrier combination of time-difference measurement that is uncorrelated with the first combination. Finally, an alternative method is based on a combination of carrier signals in a common frequency band which allows estimating the biases individually.

Abstract: An electromechanical functional module and associated process for production thereof, which includes at least one transducer, at least one upper fiber cover layer, which is nonconducting and is positioned over the at least one transducer having a first electrode and a second electrode, at least one lower fiber cover layer, which is nonconducting and is positioned below the at least one transducer, at least one fiber interlayer, which is nonconducting with at least one cut-out for accommodating the at least one transducer, at least one upper electric contract strip that is integrally connected to the at least one upper fiber cover layer and in contact with the first electrode of the at least one transducer, and at least one lower electric contract strip that is integrally connected to the at least one lower fiber cover layer and in contact with the second electrode of the at least one transducer, wherein the at least one upper fiber cover layer, the at least one lower fiber cover layer and the at least one tra

Abstract: An electromechanical functional module and associated process for production thereof, which includes at least one transducer, at least one upper fiber cover layer, which is nonconducting and is positioned over the at least one transducer having a first electrode and a second electrode, at least one lower fiber cover layer, which is nonconducting and is positioned below the at least one transducer, at least one fiber interlayer, which is nonconducting with at least one cut-out for accommodating the at least one transducer, at least one upper electric contract strip that is integrally connected to the at least one upper fiber cover layer and in contact with the first electrode of the at least one transducer, and at least one lower electric contract strip that is integrally connected to the at least one lower fiber cover layer and in contact with the second electrode of the at least one transducer, wherein the at least one upper fiber cover layer, the at least one lower fiber cover layer and the at least one tra

Abstract: An electromechanical functional module and associated process for production thereof, which includes at least one transducer, at least one upper fiber cover layer, which is nonconducting and is positioned over the at least one transducer having a first electrode and a second electrode, at least one lower fiber cover layer, which is nonconducting and is positioned below the at least one transducer, at least one fiber interlayer, which is nonconducting with at least one cut-out for accommodating the at least one transducer, at least one upper electric contact strip that is integrally connected to the at least one upper fiber cover layer and in contact with the first electrode of the at least one transducer, and at least one lower electric contact strip that is integrally connected to the at least one lower fiber cover layer and in contact with the second electrode of the at least one transducer, wherein the at least one upper fiber cover layer, the at least one lower fiber cover layer and the at least one trans

Abstract: An electromechanical functional module and associated process for production thereof, which includes at least one transducer, at least one upper fiber cover layer, which is nonconducting and is positioned over the at least one transducer having a first electrode and a second electrode, at least one lower fiber cover layer, which is nonconducting and is positioned below the at least one transducer, at least one fiber interlayer, which is nonconducting with at least one cut-out for accommodating the at least one transducer, at least one upper electric contract strip that is integrally connected to the at least one upper fiber cover layer and in contact with the first electrode of the at least one transducer, and at least one lower electric contract strip that is integrally connected to the at least one lower fiber cover layer and in contact with the second electrode of the at least one transducer, wherein the at least one upper fiber cover layer, the at least one lower fiber cover layer and the at least one tra