Wireless networks these days are very common and for the most part are easy to design and deploy in a small office environment. When we get into bigger deployments site surveys must be done to ensure full coverage of the environment. This is when the design is a little more difficult and the outcome is not always desireable. The difficulty is not in providing a comprehensive site survey, but in convincing the customer that it is required and must be paid for. As always the delicate balance between the cost of the hardware for a project and the cost to deploy the project is skewed by the complexity of the technology.
It is a hard thing to swallow, but the reality is that the cost of planning design and deployment can often be more than the cost of the hardware itself.
Consider the outdoor access-point coverage, required for a shipping yard, lumber yard, car dealership etc. For outdoor deployments there is less interference – that’s a good thing, but the distances are increased and the antenna mounting locations can be difficult to control. To really understand the amount of coverage a wireless survey is required and this survey is pretty much equal in effort to a full deployment.
At a minimum two people are required to perform a site survey. One to position the access point and the other to check the coverage area and perform signal testing. For each coverage area this process must be repeated until the desired coverage is achieved. This can become difficult if you do not have the right equipment to do the job. A wireless survey kit can go a long way to making the job easier. Cisco use to sell survey kits for the old AP350’s but I don’t think they have kits anymore. You can easily build your own – it’ll cost you a few bucks but only once. Here is a quick list of what would go into a kit.
1. Access-Point with External RP-TNC connectors pick the model that has all capabilities built-in – A,B,G and N
2. A couple of different Antenna’s – Omni, Yagi and Wall Mount.
3. Antenna Cables – different lengths so you can mimic a production environment. You can also use an attenuator to mimic the cable loss.
4. Some sort of power source that will last for the entire survey period.
5. Survey Software – Not a requirement but it will make your life a lot easier. You want to check signal level and signal quality, but you also want to run some data just to make sure the integrity of the data is maintained. As more and more companies are running voice over wireless this is a critical step.
Even after the survey is complete, leave room for change orders – until it is fully deployed you won’t know what gaps may exist.