propagation.htm

from John Waters

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PolarPlot is a program that lets you see what the polar diagram of your rotatable beam antenna actually looks like where it is operating.  It has been written for the ham radio community interested in knowing more about their beam antennas. 

You can download and try out PolarPlot to see if you like the look of it. The program will operate fully for 30 runs during a 15 day period. You can check that it works on your equipment and take take a look at some sample antenna plots.  All that is needed (apart from your rig of course!) to measure your own or someone else's antenna is a standard PC with a sound card.  For more information look at this copy of the user guide  PolarPlot runs on Windows 95/98, Windows/NT4 and Windows 2000, desktop machines and even laptops!

With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes - compare the design pattern to the actual - gain a better understanding of the antenna. You can view the plot on a circular or rectangular grid, with either log or linear scales. The screenshot on the right is a 2m beam before and after a re-build - the blue is the before, and the red is the after!. Take a look at some more screenshots of PolarPlot in action.

http://www.g4hfq.co.uk/index.html

View.exe

A set of Public Domain programs for plotting microwave (broadband amateur television) line of sight radio pathways,using NGR/Locator Grid. Draws Localmaps around a given point. Point-to-point Terrain paths and optical horizon Views.

Mainland Britain only. MicroSoft DOS or Windows.

http://www.wlan.org.uk/downloads/g4jnt-atv.zip

Terrain.exe

Radio Mobile Version 3.5.4 Radio Propagation and Virtual Mapping Freeware by VE2DBE.

An up-to-date Windows program useable world-wide requiring additional mapping and topographical data obtainable from other external sources.....

Elevation data For most of the world is available

The software also provides 3D views, stereoscopic views, and animation.

Freeware by VE2DBE

http://www.cplus.org/rmw/english1.html

Getting started in

"Radio Mobile"

G8GTZ (20/3/2002)

Radio Mobile is a fantastic program for predicting links and radio coverage. However, it does take some time to get to know and the user documentation is not the best! So here is the G8GTZ how to get started guide.

Download in original Word format

Noel - G8GTZ

http://www.cplus.org/rmw/getting_started.html

ONLINE Terrain Plot

(United Kingdom Only)

This page is an online implementation of a program used by UK radio amateurs since 1993. Credit is due for the original Power Basic design, logic and implementation Andy Talbot G4JNT

http://www.megalithia.com/elect/terrain.html

NetStumbler.com is a website dedicated to wireless networking technology and security of all kinds. We do our best to keep our website up to date with the latest wireless news - we really appreciate user submitted stories. NetStumbler.com is also the official home of the NetStumbler software.

NetStumbler is a Windows utility for 802.11b based wireless network auditing written by Marius Milner.

http://www.netstumbler.com/

March 2004

Features

Multiple packet capture sources
Runtime network sorting by AP MAC address (bssid)
IP block detection via ARP and DHCP packet dissection
Cisco product detection via CDP
Ethereal and tcpdump compatable file logging
Airsnort-compatable "interesting" (cryptographically weak) logging
Secure SUID behavior
Cloaked network detection
Grouping and custom naming of SSIDs
Multiple clients viewing a single capture stream
Graphical mapping of data
Cross-platform support (handheld linux and BSD)

What is it?

Kismet is a 802.11b wireless network sniffer. It is capable of sniffing using almost any wireless card supported in Linux, including Prism2 based cards supported by the Wlan-NG project (Linksys, Dlink, Rangelan, etc), cards which support standard packet capture via libpcap (Cisco), and limited support for cards without RF Monitor support.
top

Author: Mike Kershaw (dragorn@kismetwireless.net)

http://www.kismetwireless.net/index.shtml

5/2002

It is becoming increasingly difficult not to be caught up in WiFi traffic since so many homes and businesses are taking advantage of this technology. Unfortunately, the ever-decreasing prices and ever-improving ease-of-use has also caused wireless networks to be real security problems within businesses and institutions. At a personal level, it would be useful to have a way to know where these public "hotspots" are without having to carry around equipment that makes you look like an extra from a Star Trek set. At a corporate level, it would be extremely advantageous to have a means to detect rogue WiFi equipment at all company sites without having to spend many thousands of dollars on an enterprise-level WLAN detection system.

A solution may be at hand with the appearance of two "pocket-sized" 802.11 detectors on the market: the Smart ID WFS-1 and the Kensington WiFi Finder. Both devices claim to detect 802.11b and 802.11b/g traffic and report the strength of the signals. They each cost in the area of $30 USD. The question is: how well do they work and how can you use them for both personal information gathering and corporate protection?

Bob Rudis
September 2, 2003

http://www.smartid.com.sg/

March 2004

Understanding and Using Antenna Radiation Patterns
By Joseph H. Reisert

Each antenna supplier/user has different standards as well as plotting formats.  Each format has its own pluses and minuses.  Hopefully this technical note will shed some light on understanding and using antenna radiation patterns.

All antennas have directional qualities.  They do not radiate power equally in all directions.  Therefore, antenna radiation patterns or plots are a very important tool to both the antenna designer and the end user.  These plots show a quick picture of the overall antenna response.
However, radiation patterns can be confusing. 

http://www.astronantennas.com/radiation_patterns.html

March 2004

propagation.htm

from John Waters BSc Llanidloes Community WLAN

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PolarPlot is a program that lets you see what the polar diagram of your rotatable beam antenna actually looks like where it is operating.  It has been written for the ham radio community interested in knowing more about their beam antennas. 

You can download and try out PolarPlot to see if you like the look of it. The program will operate fully for 30 runs during a 15 day period. You can check that it works on your equipment and take take a look at some sample antenna plots.  All that is needed (apart from your rig of course!) to measure your own or someone else's antenna is a standard PC with a sound card.  For more information look at this copy of the user guide  PolarPlot runs on Windows 95/98, Windows/NT4 and Windows 2000, desktop machines and even laptops!

With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes - compare the design pattern to the actual - gain a better understanding of the antenna. You can view the plot on a circular or rectangular grid, with either log or linear scales. The screenshot on the right is a 2m beam before and after a re-build - the blue is the before, and the red is the after!. Take a look at some more screenshots of PolarPlot in action.

http://www.g4hfq.co.uk/index.html