Sharif Digital Repository

One of the important jobs of ESM and Elint receiver is to find the direction of arrival of the targets. Also DOA estimation has applications in guiding missiles and jammers location, position finding using of multiple DF systems which are placed in different locations is the most important use of this type of system.
A DF system has multiple parts: receiver, algorithm and arrays of antennas.
Amplitude comparison algorithms are more simple but on the other hand phase comparison algorithms prepare more accurate estimation. In this thesis these algorithms are simulated and to each other. And it will be concluded that, in the application being test, the "MUSIC" algorithm is the best.... 

For a manned space mission to Mars, one of the essential requirements is to have a two-way, uninterrupted communication link.Three Mars Synchronous Satellites (MSS), are proposed to ensure the telecommunication link in all locations on Mars (except its poles) at any time. At any given moment, at least two of the three satellites (MSS) is connected to the Deep Space Communication Complex (DSCC) (NASA Earth Station). But the use of MSS satellites is not adequate during the periods of solar conjunction and solar opposition. Due to the fact that the sun blocks or weakens the receiver signal, a solar orbiting satellite (SOS) is proposed to maintain the communication link at this condition....