The Art (Science?) of Radio Propagation came a long way in the twentieth century. With the
help of modern computers we can ALMOST predict what's going to happen over any given link!
With the ubiquitous PC on almost every desk and a little software like we offer below, much of
the "Black Magic" is removed from radio link design. While there is certainly room
for improvement in this field, link design is now rather mundane. To be sure, Hams and many
others have exploited anomolous propagation modes for years -- but for average everyday
situations try one of these programs or investigate some of these references!
This is a radio frequency propagation calculator for the transmission
path between an RF transmitter and a receiver. It is aimed mainly at
short range radio applications, such as in-building LAN and point-to-
point links up to a few km where there is a direct line-of-sight or a
simple diffraction profile, or a modified range law model, but it can
also support calculations for satellite, aeronautical and space
communications where the line-of-sight model can be applied. It is
useful to both ham operators and radio professionals.
The knife-edge diffraction calculation option allows the effects of a
hill or other obstruction to be taken into account. Loss factors can
be included, e.g. building penetration loss.
Maximum range and path budget margin are rapidly calculated and
viewed while modifying the input parameters conveniently using the
main graphic window. The parameters are displayed against a
bitmap of radio stations and a hill to visually aid entry of the
various parameters. A text-mode window can be opened up to list
the results, with additional information, and then output to an Ascii
file. A built-in help file includes information about the various
parameters and calculated results and includes further information
about changes in this version.
Special requirements: Windows 3.1, also 95 & NT compatible.
Changes: Bugs fixed, added window sizing and font selection to improve
compatibility with user systems, added some intermodulation calculations.
RCalc III provides a convenient means of evaluating wireless control
systems given a few basic system parameters. RCalc III is the
result of three years of day-to-day use, testing, and validation by
several RF and systems engineers. After the RF transmitter and
receiver capabilities are entered, the user may estimate
communications range performance, determine allowable path loss,
calculate antenna factor, or determine which system parameters need
to be improved to meet a specific communications range goal. RCalc
III will base these calculations on either ideal propagation or,
optionally, use a lossy propagation model to account for real-world
non-idealities. In addition, a utility is provided to calculate dB
losses due to impedance mismatch, and a maximum transmitter power
lookup utility is provided to assist with meeting US and Canadian
EMC regulations. The registered copy of RCalc III will allow the
user to evaluate system performance given the constraints of
operating under the many different foreign EMC regulations: maximum
transmitter output power and allowable frequencies are provided for
many countries. The list of supported countries will be updated
periodically and distributed free to registered owners who purchase
diskettes. The serial number and registration code is valid for
all future releases of RCalc III.
The Propagation models software contains ICEPAC, VOACAP, and REC533. You can also access
the Irregular Terrain Model (ITM) (Longley-Rice), the IF-77 Wave Propagation Model (Gierhart-Johnson),
and the ITS Propagation Measurement data - UHF/VHF measurements at this site.