Cisco Cisco Catalyst 6500 Series 7600 Series WebVPN Services Module Libro blanco
Wireless LAN Design Guide for High Density
Client Environments in Higher Education
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AP Placement Options
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The most common method of achieving even coverage is to evenly space the APs directly over the clients they will serve. There
are multiple options to accommodate overhead mounting of the APs in an unobtrusive manner. Although many people do not
consider any AP to be a welcome stylistic addition to a room, APs with internal antennas can be flush mounted to a variety of
surfaces and offer an option with less impact on a room’s aesthetics. In these cases, a flush mount antenna can be much less
obtrusive. External antennas increase the cost and complexity of the installation slightly, but can be justified if the end result is
the ability to cover the room at a sufficient density and meet aesthetic requirements. Once the decision is made to incorporate
external antennas, numerous options are opened for shaping the RF cell through the use of directional antennas. Channel reuse
in 2.4 GHz can be achieved in smaller spaces by using directional antennas overhead. Ceiling height and antenna choice will
determine cell boundaries and taking measurements is required.
The most common method of achieving even coverage is to evenly space the APs directly over the clients they will serve. There
are multiple options to accommodate overhead mounting of the APs in an unobtrusive manner. Although many people do not
consider any AP to be a welcome stylistic addition to a room, APs with internal antennas can be flush mounted to a variety of
surfaces and offer an option with less impact on a room’s aesthetics. In these cases, a flush mount antenna can be much less
obtrusive. External antennas increase the cost and complexity of the installation slightly, but can be justified if the end result is
the ability to cover the room at a sufficient density and meet aesthetic requirements. Once the decision is made to incorporate
external antennas, numerous options are opened for shaping the RF cell through the use of directional antennas. Channel reuse
in 2.4 GHz can be achieved in smaller spaces by using directional antennas overhead. Ceiling height and antenna choice will
determine cell boundaries and taking measurements is required.
In Figure 13, assuming the room is 9000 square feet, using the internal antenna enables AP nine channels of 5 GHz, and three
channels of 2.4 GHz to be provided comfortably. Using an external omnidirectional antenna, the results would be much the
same. Using omnidirectional antennas on 5 GHz and directional antennas on 2.4 GHz, one, two, or three additional 2.4 GHz
channels could be added within this space. Throughput improvements would largely be gained by more even client distribution
and less resulting CCI at the client. Some additional capacity will be gained, but only to the extent that CCI can be eliminated
between the cells and this will depend on ceiling height, antenna pattern, and power levels in 2.4 GHz.
channels of 2.4 GHz to be provided comfortably. Using an external omnidirectional antenna, the results would be much the
same. Using omnidirectional antennas on 5 GHz and directional antennas on 2.4 GHz, one, two, or three additional 2.4 GHz
channels could be added within this space. Throughput improvements would largely be gained by more even client distribution
and less resulting CCI at the client. Some additional capacity will be gained, but only to the extent that CCI can be eliminated
between the cells and this will depend on ceiling height, antenna pattern, and power levels in 2.4 GHz.
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