Tecnología De Mapeo

Marco Teórico

A wireless site survey, sometimes called an RF site survey or wireless survey, is the process of planning and designing a wireless network, in particular an 802.11 Wi-Fi wireless network, to provide a wireless solution that will deliver the required wireless coverage, data rates, network capacity, roaming capability and Quality of Service(QoS). The survey usually involves a sitevisit to run tests to determine the presence of RF interference and identify optimum installation locations for access points. This requires analysis of building floor plans, visual inspection of the facility, and usage of site survey tools. In addition, interviews with IT management and the end users of the wireless network are important to determine the design parameters for the wirelessnetwork.
When conducting a wireless site survey, it's very important to identify an effective range boundary, which defines the minimum signal levels needed to support the intended application. This involves determining the minimum SNR needed to support performance requirements.
Independent studies have shown that most of the Wi-Fi wireless networks installed today are not optimally designed orinstalled, and many do not provide the service that they were intended to. Because of this, stringent wireless site surveys, planning and design exercises are becoming essential, especially to support the new breed of wireless services such as Mobile VoIP and real-time location services.
Wireless site survey can also mean the walk-testing, auditing, analysis or diagnosis of an existing wireless network,particularly one which is not providing the level of service required.

Como realizar un Site Survey
The ultimate goal of a wireless site survey is to determine the number and placement of access points (or mesh nodes) that provides adequate signal coverage throughout a facility or city area.  With most implementations, “adequate coverage” means support of a minimum data rate or throughput. Inorder to perform a successful survey, you’ll need to relate the required performance to a value that survey tools measure, such as SNR. A wireless site survey also detects the presence of RF interference coming from other sources that could degrade the performance of the wireless LAN. 
The need and complexity of a wireless site survey will vary depending on the facility. For example, a smallthree room office may not require a site survey. This scenario can probably get by with a single Wi-Fi access point (or router) located anywhere within the office and still maintain adequate coverage. If the access point encounters RF interference from another nearby wireless LAN, you can likely choose a different channel and eliminate the problem.  
A larger facility, such as an office complex,airport, hospital, or warehouse, or an outdoor area like a city, generally requires an extensive wireless site survey. Without a survey, users will probably end up with inadequate coverage and suffer from low performance in some areas.  
Condiciones a Considerar
1. Understand the wireless requirements. In order to identify optimum locations for access points or mesh nodes, you must have a goodunderstanding of specific requirements for the network that impacts signal coverage. For example, maximum range between a client device and the access point decreases as data rate and resulting performance increases. Thus, you need to know the target data rates (and throughput) to correctly interpret survey results. Also, client devices may have relatively low transmit power, which must be taken intoconsideration when using most site survey tools. Be sure to identify the technologies that the network will implement, such as 802.11g or802.11n and perform the survey with these technologies in mind.
2. Obtain a facility diagram. Before getting too far with the site survey, locate a set of building blueprints or city maps. If none are available, prepare a drawing that depicts the location of...