Satellite navigation is growing in importance for civil applications. Nowadays, there are two systems operational, GPS of the USA and GLONASS operated by Russia. In addition, augmentations of these systems and future new systems are planned, in order to increase the reliability and accuracy of satellite navigation systems. In order to benefit from these future improvements of satellite navigation systems there is a need for advanced receiver developments which are able to enhance the receiver performance needed in many applications. For example, in the landmobile area the reception of the satellite signal will be strongly influenced by environmental conditions whilst high precision often is needed in the measurement of data. Thus some aspects of these technologies with respect to concepts and techniques for receiver development with a high level of digitalization and receiver autonomous reduction of errors will be described in this paper. Also the effects of an implementation of additional sensors will be discussed which may increase the accuracy and integrity of the navigation system. Furthermore it will be shown, that the efficiency of the satellite signal reception can be improved using antennas with special characteristics leading to an enhanced availability of the signals. Copyright © 2000 John Wiley & Sons, Ltd.
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