Radio Modem Signal Strenght Monitor: a
program to monitor the strenght of the signal (connection) of
a Radio (Wireless) Modem
Recently I involved myself in the task to try to connect a modem in an isolated house, far from wireless civilization.
Basically I had to call the only cable phone line available in the "in the middle of nowhere house" from a laptop. The area was in a wood with a very week, if not null, signal.
I had to:
- find the way to extend the built in antenna of my modem to go around the house looking for the signal (rabdomante phase)
- understand how to built a decent antenna to get the most of the "so to find" signal (rabdomante tool)
- catch the variation of the signal with my erratic moves around the rooms.
This had to be done with a minimal (if not null) expense.
the web I couldn't find any suitable software (only for Networks wireless adapters, not for Radio Modems - ok, it may be my fault).
In addition I casually faced the challenge
of the Napoliwireless site for proving that that the home made
parabolic antennas were suitable for mobile phones also (i.e. GSM). This was for me.
Soon I discarded to buy something in internet because too expensive (50
to 300 €) and too long delivery. Then I discovered that the strenght of
a Wireless Router Signal (2.5 GHz) can be easily increased (by almost 12 dBm) with an easy and cheap parabolic antenna made with alluminium foil (see freeantennas.com) or a "cantenna" (see scritturaalternativa.blogspot - in italian).
I then found that the GSM frequency is 900 and 1800 MHz (i.e. 0.9 - 1.8
GHz), so no far from the GHz design. Since the frequencies are similar
then the antennas can be similar and what is suitable for the Wirelss
can be good for GSM. Then I recovered a Digital TV Signal Stilo Antenna
(8 cm) and discovered that the frequencies are again similar to the
Now I was needing a good tool for measuring the signal strenght, better
that those available in the connection softwares. More precisely I was looking for a clear numeric display and a proportional acustic sound (with the chocolate inside) to allow me to walk while having an immediate feedback of the strenght of the signal .
Then I decided to write one by myself and this is the bare and simple code resulting from.
program scans the PC for the available COM ports and relevant
attached devices. Then it uses a simple AT+GMM command sento to the
modem to get the signal strenght reply, transform in dBm and show it on a big textbox and emits a sound tone whose volume and frequency are proportional to the radio modem signal strenght. In addition it writes a LOG textbox. Funny
to remark that, after of some esperiments, I discovered that the small
antenna integrated in the radio modem (removed and replaced with the
home made ones) was equivalent to the home made parabolic "aluminium
foil" device (see www.freeantennas.com), but at least I was able to
walk around looking for the best signal with the antenna only and not the laptop.
At today I still
have to go to the "in the middle of nowhere house" to test the sw and
the various antenna(s) build, but the most of the fun has already
Later on I will improve this page adding direct links to my discoveries.
Written in PureBasic 4.40 B5 (x86)
- (see www.purebasic.com).
Code and binary are provided FREEWARE.
modify at YOUR OWN WISH and RISK.
Just explode the file in the any folder and run Tracer.exe.
This program doesn't make any change to your folders (system or not).
It just read the input file and creates the output files where you want
Just remove the folder(s).