Global satellite navigation system (GNSS) is by far the most cost-effective outdoor positioning technology currently available and used for many types of applications. In some cases a user may face difficult conditions, like restricted access to the navigation satellites due to natural or man-made phenomena. This paper presents an idea of an integrated positioning system capable of functioning under limited visibility conditions of navigation satellites. The system includes a digital antenna array, channels for converting radio navigation signals, a phase difference meter, a gyro platform with 3 gyros, an altimeter and a special calculator. With the help of mathematical modeling, the accuracy characteristics of the system are investigated by determining the coordinates of the carrier under conditions of a small number of available satellite signals.
The problem of space debris utilization is quite relevant nowadays and has a global character. The space industry experts from all over the world are working on the task of removing space debris. This article proposes the method of determining space debris coordinates by means of the airborne equipment of a space service vehicle. The set of airborne equipment includes a global navigation satellite system receiver, an inertial navigation system and a laser radar. To study the accuracy characteristics of the proposed method under different initial conditions a series of simulations was performed. They showed that the accuracy of determining space debris coordinates becomes higher with the reduction of the distance between the debris and space service vehicle. Stringent requirements for the accuracy of determining the orientation of the coordinate frame of the space vehicle are essential for providing the accuracy characteristics of the method.