Full name of the package: Space VLBI Principle Investigator Software
Developer authors and institution: R.Taylor, G. Young, Department of Physics and Astronomy, University of Calgary, Canada for the Canadian Space Agency.
Purpose: Planning and design of VLBI experiments for the Radioastron or VSOP Space VLBI missions and technical preparation of observing proposals for both missions.
Intended Users: Potential investigators using Radioastron or VSOP. The user interface is reasonably facile and intuitive, however an understanding of the basics of radio interferometry is required.
Hardware Requirements: The software will run on any level of IBM PC clone. However an 80286 or equivalent platform with with EGA screen resolution is recommended as a minimum configuration. Because extensive use is made of colour to encode information in both the user interface and visualizations, a colour monitor is highly recommended.
Software Requirements: The package is distributed in precompiled form with executable code and associated files. The progams will run under DOS or windows environments. No additional software is required.
Capabilities: The software is capable of a range of functions required to carry out technical planning of space VLBI observations and to assess the feasibility of a scientific program. In addition there are visualization aids to allow the users to examine and extrapolate the impact of technical constraints on the scientific goals. These include: plotting of sub-satellite tracks to display the impact of telemetry station availablility on spacecraft tracking; generation of u-v tracks for both total intensity and linear polarization tranform plane coverage, graphical display of ground radio telescope (GRT) availability and source visibility during an experiment; signal-to-noise ratio versus time on satellite-ground baselines for specified source intensity distributions; allsky u-v coverage displays for planning of survey mode observations; generation of visibility files for transfer to VLBI image processing packages for imaging simulations and checks of observating plans against operational constraints of both the spacecraft and participating GRT's. All calculations include the static and operational constraints of the spacecraft and the GRT's.
User Interface: A keyboard-driven, graphical user interface. Most observing parameters are displayed on the main user interface display and can be changed interactively. Default values of observing parameters, and spacecraft and ground station properties and constraints are contained in ASCII files that can be edited by the user.
I/O Data Format: Input is via keyboard and disk files. Output is to screen only at present and will soon include Postscript laser printer output.
Documentation: A TeX formatted User Manual is included on diskette.
Distribution: From the Canadian Space Agency with the Radioastron mission users' handbooks on floppy diskette(s) and via anonymous ftp from ``bear.ras.ucalgary.ca''.
Future developments: Addition of hardcopy laser printer output in Postscript format from all routines. Generation of FITS visibility data files from simulated observations of model brightness distributions. Generation of an "observing" file including a technical description of the observing plan in standard format for input to technical assessment of space VLBI proposals.