Wireless WAN Howto

Introduction

What is a Wireless WAN?

A Wireless WAN (Wide Area Network) is a computer network using wireless networking hardware to transfer data between locations that may be across the road or across town.

Some recent developments have made the use of wireless WAN technology very attractive.

· Lower equipment costs

· High speed wireless products

· Allocation of license free bands

· Growth of the internet

Wireless WAN Uses

Internet Access

Share an Internet account with your neighbors.

Mobile Connectivity

Surf the net or answer email on the verandah or by the pool.

Voice Calls

Use VOIP to make phone calls for free.

Network Gaming

Take advantage of the low latency of wireless networks with action network games.

Security Alarm Monitoring

Connect your security system to the network and monitor it remotely.

Video Surveillance

Keep an eye on things using cheap web cameras over the network.

Video Conferences

Use the high speed offered by wireless with video hook ups to your friends.

Wireless WAN Components

Wireless Network Card

This is basically a radio that transmits and receives data at high speed. They are available in PCMCIA for notebook computers or PCI, ISA or USB for desktop computers. Most manufacturers simply use their PCMCIA card with an adapter to suit desktop computers.

Pigtail Adapter

Because of their size, most wireless network cards have a tiny antenna socket which needs to be converted to an 'N' type connector used on good quality low loss antenna cable. A 'pigtail adapter' is used for this.

Low Loss Antenna Cable

Used for connecting to an antenna mounted on your rooftop and needs to be kept as short as possible to minimize signal loss. Only use a high quality cable Suitable for use at 2.4 GHZ. These cables are available already terminated with N connectors Make sure to get the correct gender connectors to suit your antenna and pigtail adapter

Antenna

Directional

These antennas focus the signal in one direction to enable greater range. They are generally used in point-to-point configurations or at the client end in point to multi point configuration.

Omnidirectional

This antenna's provide equal coverage in any direction and are generally used at a central location to provide service to multiple clients. One drawback is interference is received from all directions also.

Sector

These antennas are used at a central location to provide service to mutiple clients but where an omnidirectional is not required. This also enables better performance as the signal is not spread over 360 degrees but only a sector of it. An example would be on the side of a hill where clients may only be in a 180 degree arc and signal would be absorbed by the hill if an omnidirectional was used.

Topology

Point to point

This is the most basic configuration where two locations are connected directly together using directional antennas. Because both locations are transmitting and receiving in one direction only you can achieve the longest links this way.

Usually it is used to network two computers together although you can also connect a computer to a network or connect two networks together in this way.

Point to multipoint

This is where multiple computers and/or networks using directional antennas are connected to a central location using an omnidiretional or sector antenna. An example of this would be a wireless ISP who could service many remote clients from a central location.

Installation

The first thing that must be done is to establish if there is line of sight between locations. This usually involves climbing on to the roof with a par of binoculars or a telescope to do a visual evaluation. Generally if the remote location can be seen the link will be successful.

The next step is to mount the antenna. Care must be taken here to ensure the antenna is not allowed to sway in the wind as this could cause the link lo be unstable in adverse conditions. The antenna usually comes with all the necessary hardware to enable mounting on a pole. If your rooftop does not have an existing suitable pole a visit to your local hardware store should remedy the problem. Its also important that the pole is mounted perfectly straight because even a couple of degrees off centre may not seem like much but it makes a huge difference over a few kilometres and may cause you to over or undershoot your target.

When connecting the low loss antenna cable be sure to hold the female connector firmly while screwing on the male otherwise for much stress could be placed on the termination causing the connector to loosen or come off. The other thing that can cause damage to the connector terminations is failing to unroll the cable fully before making the connections.

The connection should then be wrapped in self vulcanizing tape to keep it water tight.

Make sure water cant run down the cable and in to the back of your computer by leaving a loop where the cable enters the house.

The other end of the cable can then be connected to your wireless card via your pigtail adapter.

Wireless WAN projects

Existing Groups

See http://www.x.net.au/coverage.html for a list of wireless networks in progress.

Wireless WAN Resources

Australian Communications Authority

Xnet Wireless

Send corrections and suggestions to info@x.net.au