Cisco Cisco Aironet 3500p Access Point Libro blanco
© 2011 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public Information.
Page 4 of 8
Continuing with the 50,000-seat venue example, a minimum of 156 access points would be needed to provide
sufficient capacity and coverage throughout the bowl area. More access points would be recommended to
accommodate the inevitable growth in the number of Wi-Fi-enabled devices at the venue. Additional access points
would of course also be needed for other venue areas (for example, concourse, suites, back office, and parking
lots) such that the total number of access points for the 50,000-seat venue would be about 400. By designing for
coverage and capacity that meet challenging access requirements throughout the stadium, service providers,
teams, and stadium operators can satisfy subscriber needs, complement the fan experience, and enable new
revenue opportunities.
sufficient capacity and coverage throughout the bowl area. More access points would be recommended to
accommodate the inevitable growth in the number of Wi-Fi-enabled devices at the venue. Additional access points
would of course also be needed for other venue areas (for example, concourse, suites, back office, and parking
lots) such that the total number of access points for the 50,000-seat venue would be about 400. By designing for
coverage and capacity that meet challenging access requirements throughout the stadium, service providers,
teams, and stadium operators can satisfy subscriber needs, complement the fan experience, and enable new
revenue opportunities.
Antennas and Managing Co-channel Interference
The Cisco Connected Stadium Wi-Fi solution includes special-purpose antennas that are critical to supporting
small-coverage cells and high capacity throughout the venue’s crowded areas. Deploying hundreds of access
points at a venue with all access point cells designed to simultaneously achieve high capacity can be a daunting
task. The limiting factor in a design of this density is typically co-channel interference. With only three non-
overlapping Wi-Fi channels at 2.4 GHz, frequency reuse is high and as the example above shows, cells using the
same channel can be within 100 feet of each other. Enabling high capacity for all cells requires minimizing the
propagation of RFs outside each cell’s intended coverage area. The combination of low transmit power and highly
directional antennas is effective in containing an access point’s transmitted RF energy to the cell it covers, severely
limiting the RF energy that the access point receives from devices outside of its cell. This strategy supports a
greater number of smaller high-capacity cells than is otherwise possible (Figure 3).
small-coverage cells and high capacity throughout the venue’s crowded areas. Deploying hundreds of access
points at a venue with all access point cells designed to simultaneously achieve high capacity can be a daunting
task. The limiting factor in a design of this density is typically co-channel interference. With only three non-
overlapping Wi-Fi channels at 2.4 GHz, frequency reuse is high and as the example above shows, cells using the
same channel can be within 100 feet of each other. Enabling high capacity for all cells requires minimizing the
propagation of RFs outside each cell’s intended coverage area. The combination of low transmit power and highly
directional antennas is effective in containing an access point’s transmitted RF energy to the cell it covers, severely
limiting the RF energy that the access point receives from devices outside of its cell. This strategy supports a
greater number of smaller high-capacity cells than is otherwise possible (Figure 3).
Figure 3. Connected Stadium Wi-Fi Deployment
A critical component in containing RF energy to the access point’s intended coverage cell is proper antenna
mounting, which is often constrained by limited mounting resources and the absolute requirement that the
antennas not obstruct fans’ views. Mounts must also be secure enough to handle wind conditions at outdoor
venues and other outdoor coverage areas such as parking lots. In addition, venues have aesthetic guidelines that
must be maintained – an unsightly antenna that could detract from the appearance of the venue will not be
tolerated.
mounting, which is often constrained by limited mounting resources and the absolute requirement that the
antennas not obstruct fans’ views. Mounts must also be secure enough to handle wind conditions at outdoor
venues and other outdoor coverage areas such as parking lots. In addition, venues have aesthetic guidelines that
must be maintained – an unsightly antenna that could detract from the appearance of the venue will not be
tolerated.
Cisco has designed a new dual-band, high-gain multiple-input multiple-output (MIMO) antenna, the Cisco 25137NP
Antenna, specifically to address the tight beamwidth, constrained mounting, and aesthetic requirements needed for
high-density venue seating areas (Figure 4).
Antenna, specifically to address the tight beamwidth, constrained mounting, and aesthetic requirements needed for
high-density venue seating areas (Figure 4).