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The measurement of static and dynamic unbalance of satellite is carried out on vertical dynamic balancing machine (VDBM) [1]. The Velocity pickup is a transducer in VDBM, which measures the dynamic...

Presented in this paper is an overview of passive intermodulation (PIM) in microwave space systems. Application of some of the PIM analysis and prediction techniques to the Indian national communication satellite, INSAT-2E, has been discussed in some detail. PIM control measures and PIM testing techniques that are proposed to be adopted in the design of the communication payload have been briefly summarized.

The external surfaces of a spacecraft exposed to Earth's magnetospheric plasma can build up differential voltages which can result in an electrostatic discharge (ESD). This discharge may induce transient electromagnetic interference (EMI) in the electronics circuitry and may give rise to switching anomalies or system failure under certain environmental conditions. This paper outlines the development of Lumped Element Model (LEM) of a spacecraft for surface charging studies. A numerical solution procedure using method of moments and triangular patch modelling to determine the capacitance of conducting objects in free space has been developed. Differential equations of spacecraft charging have been derived and the surface charging of INSAT-2E spacecraft has been simulated. The results obtained for INSAT-2E using LEM concept are compared with those obtained using the NASA Charging Analysis Program (NASCAP) for a similar satellite.Using LEM of a conducting plate located in free space, and with the help of cir...