Definition

According to the dictionary guidance is the 'process of guiding the path of an object towards a given point, which in general may be moving'. The process of guidance is based on the position and velocity if the target relative to the guided object. The present day ballistic missiles are all guided using the global positioning system or GPS.GPS uses satellites as instruments for sending signals to the missile during flight and to guide it to the target.

SATRACK is a system that was developed to provide an evaluation methodology for the guidance system of the ballistic missiles. This was developed as a comprehensive test and evaluation program to validate the integrated weapons system design for nuclear powered submarines launched ballistic missiles.this is based on the tracking signals received at the missile from the GPS satellites. SATRACK has the ability to receive record, rebroadcast and track the satellite signals.

SATRACK facility also has the great advantage that the whole data obtained from the test flights can be used to obtain a guidance error model. The recorded data along with the simulation data from the models can produce a comprehensive guidance error model. This will result in the solution that is the best flight path for the missile.

The signals for the GPS satellite navigation are two L-band frequency signals. They can be called L1 and L2.L1 is at 1575.42 MHz and L2 at 1227.60 MHz.The modulations used for these GPS signals are

1. Narrow band clear/acquisition code with 2MHz bandwidth.
2. Wide band encrypted P code with 20MHz bandwidth.

L1 is modulated using the narrow band C/A code only. This signal will give an accuracy of close to a 100m only. L2 is modulated using the P code. This code gives a higher accuracy close to 10m that is why they are encrypted. The parameters that a GPS signal carries are latitude, longitude, altitude and time. The modulations applied to each frequency provide the basis for epoch measurements used to determine the distances to each satellite. Tracking of the dual frequency GPS signals provides a way to correct measurements from the effect of refraction through the ionosphere. An alternate frequency L3 at 1381.05MHz was also used to compensate for the ionospheric effects.

The given explanations are quiet good.But I need more to make a seminar report on SATRACK.Please send me more.

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read this also
http://ieeexplore.ieeexpls/abs_all.jsp?arnumber=1200282
http://jhuapl.edu/techdigest/td1904/1thompson.pdf

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The SATRACK System: Development and Applications
SATRACK has been a significant contributor to the development and operational success of the Trident Weapon System, and it continues to provide a unique monitoring function that is critical to the maintenance of the U.S. sea-based strategic deterrent. This article reviews the background and evolution of this unique Global Positioning System user application (the first committed user) and discusses its support of other systems of national importance. Its connection to APLâ„¢s pioneering contributions to the development of the technology and methodology supporting successful deployment of the sea-based strategic deterrent is reviewed. Basic concepts and implementation specifics of the evolving system design are described, and its extended use and performance improvements over the past 25 years are presented.

Submitted by
Thomas Thompson, Larry J. Levy, and Edwin E. Westerfield
INTRODUCTION SATRACK was developed to validate and monitor the Trident missile guidance error model in the System Flight Test Program. It is the primary instrumentation and processing system responsible for accuracy evaluation of the Navy™s Strategic Weapon System. Instrumentation and processing systems available when the Trident Development Program began could not meet this need. APL conceived and led the development of the SATRACK system to fulfill this requirement. Prototype instrumentation required for the missile and ground station data collection functions were developed at APL to validate the concept, and we generated specifications controlling the development of the operating missile and ground station hardware. We also developed and operate the SATRACK processing facility, which includes a unique preprocessing hardware and software configuration and an extensive postprocessing analysis capability. Additionally, the APL satellite tracking facility has operated as a backup SATRACK recording site for all East Coast test flights since 1978. SATRACK fully met all its guidance subsystem evaluation requirements and also provided weapon system error model insights that would not have been possible without its unique ability to detect and allocate small error contributors to miss distances observed in the flight test program. SATRACK not only validated the Trident system accuracy, but the test-derived and -validated system error models have allowed the command authority to confidently assign and allocate targets to sea-based strategic resources. The next section will discuss the background leading to SATRACK™s development as a natural extension from APL™s role in the development of the Fleet JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 19, NUMBER 4 (1998) 437 THE SATRACK SYSTEM Ballistic Missile Evaluation System and the Navy Navigation Satellite System (Transit). Then, following a discussion of the basic concepts, this article will trace the system™s evolution: ¢ SATRACK I”A technology project to develop and demonstrate the instrumentation and processing system using the Trident I missile (1973“1983) ¢ SATRACK II”The operational system designed to meet system requirements for the Trident II missile (1983“present) ¢ Other applications”Uses of SATRACK for Army and Air Force missile test applications (1983“present) ¢ SATRACK III”Current system upgrade and future applications

i want paper presentation or material on SATRACK

hi friend you can refer these pages to get the details on SATRACK

http://studentbank.in/report-satrack-full-report

http://studentbank.in/report-satrack-full-report?page=2