README PC-VOACAP NEWS *** REVISED 06-MAR-96 *** To promote the efficient and effective use of the shortwave bands the International Broadcasting Bureau (United States Information Agency) shares its HF radio system prediction program with the shortwave users of the world. From time to time, the Voice of America Coverage Analysis Program (VOACAP) is updated to improve the accuracy or to make the program easier to use. This NEWS alert provides users with information as to the latest version of the program available on this server. Instructions for downloading and installing PC-VOACAP-DOS version may be found at the conclusion of this News item. PLEASE NOTE THAT THE VOACAP-DOS VERSION IS FROZEN AS IT IS NOW. Further development such as "S/I-Signal-to-Inference Analysis" and "NEC capability" will be available in the VOACAP-Windows version, ONLY. All new developments are expected to be completed this year. >>> 06-MAR-96: In this new updated and benchmarked version of VOACAP-Windows (Version 96.0305W): -a correction was made to the Windows COMBINE module so that the BIN operation would work correctly. -the WORLWIN plotting program was modified so that it will Color BINned maps (an output from COMBINE.) -all on-line HELP is completed. >>> 22-FEB-96: A new beta Windows version of VOACAP is now made available to all interested users for FTP(ftp.voa.gov) or for downloading from the VOA Gopher(gopher://gopher.voa.gov/1). For downloading correctly, users have to use the "BINARY" mode. Users are reminded that this prototype software is still under development and will be updated as needed; therefore some of the functions, especially the HELP function are not completed yet. Interested users who want to have direct telephone or Email technical support as well as obtaining all software updates, and quick reference guide may pay a registration fee of $500 to the developer (U.S. Dept. of Commerce, NTIA/ITS.S1, Attn: Jeanne Ratzloff, 325 Broadway, Boulder, Colorado 80303). Users now have the choice of obtaining either the VOACAP-DOS version or VOACAP-Windows version or both. The VOACAP-Windows version was developed using the Salford FTN77 compiler for Windows 3.1. To run properly, users must install the DBOS extender which comes with the software. Users need to install DBOS once. If DBOS was already installed then users may skip that part of the process. If the users install DBOS then Windows must be rebooted in order for it to take effect. Please note that SYSTEM.INI will be modified to add (after[386En]): device=dir\DBOS_RUN\WDBOS.386 (dir is installation directory). This software was developed on: -Pentium-100 -MS-DOS Version 6.22 and Windows for Workgroups 3.11 -16 MBytes ram -17 inch display using 1280x1024 raster points/256 colors. Minimum system requirements: -System running Windows 3.1 -4 MBytes ram - 16 MBytes recommended -depending on how many applications the users have open, users may obtain the message "Insufficient Memory for Application". Closing unnecessary applications or increasing the virtual memory under Control Panel - 386 Enhanced can remove this problem. -Hard Disk - 20 Mbytes + lots of extra depending on use VGA graphics card The software will work on a 640x480 display, but if possible, configure the display to use more. A 14 inch display works well with 800x600. If the display uses only 16 colors, the graphics plots will suffer. At least a 486x33MHz processor with math co-processor(a 386 will work but is too slow for any substantial work)is needed. Black & White graphic output can be made to any Windows printer. A laser printer with minimum memory (512k bytes) will work but users may need to remove the border from the plot. Color graphic hard copies - works to some devices, but some drivers do not seem to work well. PLEASE NOTE THAT VOAAREA COLOR MAP OUTPUT DOESN'T WORK WITH "HP COLOR PAINTJET PRINTER"!!!!!!!, but it appears to be the driver fault. Other color printers do work. The software has been loaded on Windows-95 and required some modification to work. ################################################################# #THE VOACAP-Windows VERSION IS INSTALLED BY PLACING VOAWIN.EXE # #IN A TEMPORARY DIRECTORY AND EXECUTING IT. IT WILL EXPLODE # #INTO 21 FILES. THEN, USING FileManager, EXECUTE THE FILE # #INSTALL.EXE. THAT WILL THEN PERFORM A NORMAL WINDOWS TYPE # #INSTALLATION. THE USER MUST SELECT THE OPTION THAT ALSO #INSTALLS DBOS IF THIS IS A FIRST TIME INSTALLATION. THIS WILL # #MAKE A ONE LINE CHANGE TO YOUR WINDOWS\SYSTEM.INI. # # # #THE USER CAN INSTALL THIS WINDOWS VERSION IN THE SAME DIRECTORY# #THAT CONTAINS THE DOS VERSION. THEY ARE COMPATIBLE WITH EACH # #OTHER. # ################################################################# >>> 7-FEB-96: An error was corrected in the subroutine LUFFY. About 14 lines from the bottom was the following code fragment: C******************************************************** 165 IF(IF.eq.1) then ! 1st frequency is good XLUF(IT) = FREQ else ! NO ITERATION, SELECT THE FREQUENCY COMPLEMENT FIRST FLOW = FREA(IF-1) FHIGH= FREA(IF) RLOW = RELIAB(IF-1) RHIGH= RELIAB(IF) IF = 13 C.....USE LINEAR INTERPOLATION XLUF(IT) = FLOW + (FHIGH-FLOW)*(PLUF-RLOW)/(RHIGH-RLOW) end if FREA(13) = XLUF(IT) RETURN END C-------------------------------- The problem is in how the program gets to 165. There is only one place in the program that branches to 165, it is inside the DO 265 IFX=1,12 loop. Inside that loop, IF (a very bad choice of names), has never been defined. The 165 fragment really wants to use IFX. This error was discovered by Greg Hand when he was using Salford Fortran compiled in a DEBUG mode and IF was some large value and thus the array FREA dimension was exceeded. The point-to-point programs now produce real graphs for Methods 11 (MUF-FOT-EsMUF) and 28 (MUF-FOT-LUF). Previously, these were "line printer" graphs. These are accessed by setting METHOD to 11 or 28 and selecting CIRCUIT (not GRAPH). Remember, GRAPH always produces contour Plots of parameters. NOTE: Even with the fix, please be CAUTIOUS when using Methods 11 and 28. Our benchmark of this change showed no differences in Methods 21 or 22 output(which includes checks of Methods 20, 25 and 30). The correction involves the calculation of the LUF which has never been thoroughly checked for accuracy. >>> 5-DEC-95: A problem with the Quadrant Antenna (Type 8) was discovered. The design frequency could not be set properly. It required some changes in HFANTPLT.EXE and ANTCALC.EXE. >>> 25-OCT-95: 1) Corrections were made to the VOACAP Method 30, a longpath/short path smoothing function. Versions of VOACAP developed after April 1995 have Method 30 which allows the user to obtain smoothed signal power predictions for ranges of 7,000 km or greater. At these distances both Method 21(long path model) and Method 22(short path model) are run. Where appropriate, a distance-weighted smoothing function is applied. Method 30 was generated by making changes to Subroutine LUFFY taken from VOACAP version 93.04. The longpath/short path smoothing function is applied if the path distance is equal to or greater than 7,000 km. The parameter which is smoothed is the predicted signal power which is expected to occur or be exceeded on 90 percent of the days of the month at that hour. Other parameters that include the signal power are also smoothed. The smoothed signal power is used to compute the median field strength (DBU), the median signal-to-noise ratio (SNR), the required power gain (RPWRG), reliability (REL), lower and upper decile ranges of the SNR (SNR LW and SNR UP), and the signal-to- noise ratio at the reliability specified by the user. (Please read HFMAP NEWSLETTER, Vol 2, No 2, Summer/Fall 1995 for details). 2) The old output variable F DAYS has been replaced with MUFday. MUFday is the fraction of the days of the month that the operating frequency will be below the mode MUF. In other words it is the fraction of days one can expect normal ionospheric reflection for the indicated most reliable mode at that frequency. Previously, F DAYS indicated the fraction of days that the operating frequency will be below the MUF mode; this may or may not be the most reliable mode shown at the operating frequency in question. (Please read HFMAP NEWSLETTER, Vol 2, No 2, Summer/Fall 1995 for details). 3) A correction was made in HFANT so that curtain arrays equipped with beam steering can be slewed in the counterclockwise direction. 4) Fortran source code for the propagation program was made available. The source code is in the subdirectory named VOACAP for the DOS version. (VOACAPW for the Windows version). 5) A proto-type of a signal-to-interference mapping capability was included. It allows the user to specify a wanted and unwanted transmitter for a common grid of receive sites. For instructions in running the programs, see file VOACAP.UM, which contains a brief user's guide to this software. This model will be expanded to point-to-point capability and improved in a future version of VOACAP. >>> 09-JAN-95: 1) Default values for man-made radio noise in VOACAP were updated to those recommended in CCIR Report 258. It was only a screen display but it may have led some users to specify higher man-made noise levels than the CCIR currently recommends. (Please read HFMAP NEWSLETTER, Vol 2, No 1, Spring 1995 for details). 2) An error was found in the signal-to-noise ratio (SNR) distribution calculation from the original IONCAP [Teters, et al., 1983]. The error was corrected. The corrected method estimates the SNR distribution in a manner consistent with ITSA-1 [Lucas and Haydon, 1966]. This correction tends to make a 2 to 4 dB decrease in the SNR and a commensurate decrease in predicted reliability. (Please read HFMAP NEWSLETTER, Vol 2, No 1, Spring 1995 for details). >>> 14-NOV-94: 1) A change was made to the Distribution of Transmission Loss table (also known as Excess System Loss). A value in the table for paths greater than 2500 km at the highest latitude and in the second time block during the Equinox was written as 115 dB (it translated to 3 months in Fall and Spring, No. and So. Hemispheres). The correct value is 11.5 dB, according to the work of Haydon and Lucas. (Please read HFMAP NEWSLETTER, Vol 1, No 3, Fall 1994 for details). 2) Another change is the replacement of output parameter SNR90 with SNRxx; the signal-to-noise ratio having a reliability equal to the user specified required reliability. SNR90 was the SNR at 90% reliability (regardless of the required reliability input by the user). 3) A new function, COMBINE, has been added to the VOAAREA program that combines multiple maps. For instructions in running the programs, see file VOACAP.UM, which contains a brief user's guide to this software. ______________________________________________________________ VOACAP is a modified version of IONCAP version 83.04 and was developed by the Voice of America over the past decade with the assistance of the Naval Research Laboratory and the National Telecommunications and Information Administration/Institute for Telecommunication Sciences. A Program Guide for VOACAP is available for sale from the National Technical Information Service (Springfield, VA 22161, USA) as document PB93-155174. A condensed User's Manual for VOACAP is supplied with the program. Neither the United States Government nor any person acting on behalf of the United States Government assumes any liability resulting from the use of this software. VOACAP and its associated documentation is provided to the public for general information and use. Comments and suggestions relative to this software or its documentation should be forwarded to the authors: Hien Van VO e-mail: Hien _Vo@beng.voa.gov United States Information Agency International Broadcasting Bureau Attn: B/EBP-Hien VO 330 Independence Ave. SW Washington, DC 20547-0001 USA FAX: +1 202-619-3484 ***************************************************************** ******Program Installation for VOACAP-DOS version************** ***************************************************************** SUMMARY: 1. Memory - must have at least 500,000 bytes available 2. DEVICE=C:\DOS\ANSI.SYS (or such) in CONFIG.SYS 3. the AUTOEXEC.BAT must contain ..\bin in the path statement 4. When files are copied to hard disk, install with: HFINSTAL Which will properly explode all .EX_ files copied. 5. After installed, execute from ..\RUN directory with: ITSHF ***************************************************************** Detailed instructions follow: The programs may be obtained by anonymous FTP from ftp.voa.gov The file voacap.exe (about 4 Mbytes) contains all that is needed. Minimum system requirements: Memory - largest executable program size of 500 Kb Hard Disk - 15 Mbytes + extra depending on use VGA graphics card ANSI.SYS in CONFIG.SYS At least a 386 processor with math co-processor HP LaserJet printer on LPT1 (for black and white copies) HP PaintJet printer on LPT1 (for color copies) Proper installation: MKDIR VOACAP - this directory will contain all VOACAP sub-directories. The name can be any name you choose. CD VOACAP- position yourself in the directory. FTP- BINARY copy file voacap.exe into this directory. The server is FTP.VOA.GOV The directory name is /pub/software/voacap Use BINARY mode! VOACAP- self-extracting .EXE will PKUNZIP into more files. HFINSTAL- this will self-extract all compressed .EX_ files. Execution MUST always occur from the sub-directory RUN. All the files in RUN may be considered temporary and may be deleted. Also, the files in the sub-directory RASTER are screen image bitmap files used for creating graphics on an HP LaserJet printer and no harm is done deleting these files. All other sub-directories contain vital data and/or executable programs. Do not delete files other than those in the RUN or RASTER sub-directories. Add the ..\BIN directory to your PATH. All .BAT & .EXE files reside in ..\BIN and the PATH must be set for them to be found. The best way is to change your PATH in AUTOEXEC.BAT to include "..\BIN" and re-boot. * * *