ALBERT

Description: QUICK provides the computer user with the facilities of a sophisticated desk calculator which can perform scalar, vector and matrix arithmetic, propagate conic orbits, determine planetary and satellite coordinates and perform other related astrodynamic calculations within a Fortran-like environment. QUICK is an interpreter, therefore eliminating the need to use a compiler or a linker to run QUICK code. QUICK capabilities include options for automated printing of results, the ability to submit operating system commands on some systems, and access to a plotting package (MASL)and a text editor without leaving QUICK. Mathematical and programming features of QUICK include the ability to handle arbitrary algebraic expressions, the capability to define user functions in terms of other functions, built-in constants such as pi, direct access to useful COMMON areas, matrix capabilities, extensive use of double precision calculations, and the ability to automatically load user functions from a standard library. The MASL (The Multi-mission Analysis Software Library) plotting package, included in the QUICK package, is a set of FORTRAN 77 compatible subroutines designed to facilitate the plotting of engineering data by allowing programmers to write plotting device independent applications. Its universality lies in the number of plotting devices it puts at the user's disposal. The MASL package of routines has proved very useful and easy to work with, yielding good plots for most new users on the first or second try. The functions provided include routines for creating histograms, "wire mesh" surface plots and contour plots as well as normal graphs with a large variety of axis types. The library has routines for plotting on cartesian, polar, log, mercator, cyclic, calendar, and stereographic axes, and for performing automatic or explicit scaling. The lengths of the axes of a plot are completely under the control of the program using the library. Programs written to use the MASL subroutines can be made to output to the Calcomp 1055 plotter, the Hewlett-Packard 2648 graphics terminal, the HP 7221, 7475 and 7550 pen plotters, the Tektronix 40xx and 41xx series graphics terminals, the DEC VT125/VT240 graphics terminals, the QMS 800 laser printer, the Sun Microsystems monochrome display, the Ridge Computers monochrome display, the IBM/PC color display, or a "dumb" terminal or printer. Programs using this library can be written so that they always use the same type of plotter or they can allow the choice of plotter type to be deferred until after program execution. QUICK is written in RATFOR for use on Sun4 series computers running SunOS. No source code is provided. The standard distribution medium for this program is a .25 inch streaming magnetic tape cartridge in UNIX tar format. An electronic copy of the documentation in ASCII format is included on the distribution medium. QUICK was developed in 1991 and is a copyrighted work with all copyright vested in NASA.

Description: With the advent of nonecliptic spacecraft orbits and the inclusion of a NASA X-Y mounted antenna within the DSN it has become apparent that the current polarization angle prediction formulas may be insufficient for future needs. This article presents a new formulation for predicting the polarization angle which properly accommodates these new features in a concise, straightforward form.