APPLICATION NOTE. Using Oberon's 1020 Series Indoor/Outdoor Enclosures in Stadiums and other High Density Venues

Transcription

1 APPLICATION NOTE Using Oberon's 1020 Series Indoor/Outdoor Enclosures in Stadiums and other High Density Venues Copyright 2014 Oberon, Inc. 4/30/2014 1

2 Stadiums, sports arenas, concert halls, auditoriums, forums, and other large public venues are launching Wi-Fi services to provide audience members with internet access and applications specific to the entertainment. This can include real time game statistics, video, on-line interactive programs, course content, and vendor order fulfillment information. Many service providers (SPs) are trying to offload mobile data traffic to Wi-Fi networks to reduce the burden on their cellular networks in public venues. Wi-Fi offers a lot more reusable bandwidth (especially in the 5 GHz band) than the SPs can offer through their cellular bands. In many cases, Wi-Fi is the only reasonable solution for mobile data services in these venues due to the density and bandwidth requirements of the users. Design, integration and installation in these larger facilities creates a unique challenge due to the overall facility size, shape, and density of users. WAP Density Requirement Wi-Fi performance will depend on adequate density of Wi-Fi Access Points, or WAP density. In the ANSI/TIA-4966 Telecommunications infrastructure for Education Buildings and Spaces standard, the recommendation for WAP density is provided in the table. Number of audience members Number of WAPs WAP for every 25 people, up to 6 WAPs This high density of WAPs may be difficult to realize in open auditorium and stadium installations, due to the absence of a suspended ceiling or convenient walls. WAPs mounted up high will tend to interfere with each other. Many designers are choosing to use low/ below/ behind seating installations, or other installation methods where the WAP is closer to floor level than the ceiling. The advantage is that this increases the number of locations for WAP installation and can help to cut down on WAP interference. The challenge is to protect the WAP, and provide for an inexpensive and reasonably aesthetic installation. Physical Protection In outdoor stadium installation, the WAP should be protected by an enclosure designed to meet NEMA 4 standards for protection from weather, liquids and dust. With such an enclosure the WAP is also protected from high pressure water spray, and, to some extent, physical tampering. An enclosure designed to NEMA4 standards may be mounted indoors and outdoors and will protect the Copyright 2014 Oberon, Inc. 4/30/2014 2

3 WAP from rain, ice, snow, dust, pressure washing and the UV present in sunlight. In indoor locations, WAPs mounted under seating or low to the ground should also be protected by an enclosure designed to protect the WAP from spilled drinks, and cleaning and washing activities. WAPs and their associated cabling mounted near or under seats or on the floor should also be protected from physical damage. The use of rugged polycarbonate enclosures with sturdy mounting features should be adequate to protect the WAP from typical physical abuse. Oberon s 1020 Series WAP enclosures are designed to satisfy the NEMA 4 requirement and are constructed of a rugged polycarbonate material. Polycarbonate is very durable, UV resistant, and is virtually transparent to the wireless signal, so it will have very little impact on the wireless performance Oberon Model 1024 wireless access point enclosure with hinged, latchable, lockable door. Copyright 2014 Oberon, Inc. 4/30/2014 3

4 Oberon Model enclosure with screw on cover Security Installation of the WAP into an Oberon 1020 series polycarbonate enclosure with a screw on cover is generally considered adequate to keep audience members from tampering with the WAP. Enclosures with screw on covers are typically Copyright 2014 Oberon, Inc. 4/30/2014 4

5 smaller than enclosures with hinges and latches, and so are a better solution for under seating installations where space is a premium. The enclosure should have recessed screws in the cover and flush mounting features to keep the WAP from catching on audience member shoes or clothing. Tamper resistant screws in the cover will help reduce tampering in environments that are left open to the public. For locations that require the WAP to be locked in place, select an enclosure with a hinged door and hasp for a padlock. Spectrum Considerations WAPs mounted outdoors are permitted by the FCC to operate over a restricted range of frequencies, relative to indoor mounted WAPS. Some manufacturers WAPs have special hardware or software settings designed specifically for outdoor applications. Consult with the WAP manufacturer s users manual for restrictions on frequency usage in outdoor installations. Aesthetics In many of these public venues, aesthetics is paramount, especially in historic auditoriums, concert halls, and some sporting arenas. Ideally, the WAP and associated cabling and mounting hardware can be blended into the environment. Oberon s 1020 Series indoor/outdoor WAP enclosures are compact, and minimize exposure of associated cabling and hardware. The Model 1020 is designed for WAPs with integrated antennas, and is the most compact indoor/outdoor WAP enclosure available. The Model 1024 is designed for WAPs with connectors and detachable or external antennas, and is the most compact enclosure for WAPs with external antennas. Unlike standard industrial NEMA 4X boxes, Oberon s 1020 and 1024 are designed with concealed hinges and smaller seems, so they are more appropriate for public venues. These enclosures can be painted to match the environment. Most paints are relatively transparent to wireless signals (avoid using metalized paint). The enclosure may be painted without voiding the WAP warranty. Thermal Considerations When mounting active (powered) equipment such as WAPs and DAS access units inside enclosures, the temperature within the enclosure increases over the ambient temperature, due to the heat dissipation of the equipment inside the enclosure. In general, WAPs consume less than 13 Watts of power, so there is not a lot of heat generated. However, within these smaller enclosures, there is a tangible temperature rise, so the operational temperature range of the WAP Copyright 2014 Oberon, Inc. 4/30/2014 5

6 should be de-rated by the temperature rise expected. (See Oberon s App Note Calculating Temperature Rise in Enclosures). Recommended De-rating Based on measurements and calculations described in the App Note above, Oberon recommends de-rating the access point manufacturer s operating temperature range by the following amounts, for the respective NEMA enclosures (these are worst case, 12 W power dissipation de-ratings. Typical power dissipation will be one half of 12 W). This is for any standards based, PoE powered (or equivalent) wireless access point. Enclosure Model De-rate Maximum Operating Temperature by º C º C º C Sun loading and other external factors may also de-rate the operating range even further. Access points (whether in an enclosure or not) placed in direct sunlight may get very hot. This will reduce the service lifespan of the WAP or may cause outright failure. Access points and their enclosure should be protected from direct sun to avoid overheating. This can be done by installing the WAP under an awning, on the north side (in nothern hemisphere) of a structure or in a sun shroud, such as Oberon s sun shroud for wireless access points Antennas Oberon offers indoor/outdoor antennas which are designed to mount directly onto the enclosure body. These antennas are rugged, gasketed, and UV stabilized, so they are suitable for outdoor duty. See Oberon s 34-DMDUAL dual band antenna, and 34-BMANT-24 and 34 BMANT-5 single band antennas at www. Oberonwireless.com. If rubber duck dipole antennas are attached directly to the enclosure, the best performance outdoors will be achieved with the antennas at a 45 degree angle. MIMO antennas work best indoors where the antenna is able to receive multiple wavefronts due to reflections. Outdoors, the antennas due not receive the reflection as they do indoors. By mounting the antennas at 45 degrees, as shown in the figure, the received signal diversity is increased, which can help performance in the outdoor environment. Make sure externally mounted antennas are at least several inches away from metal structures or poles. Externally mounted antennas must be UV stabilized to avoid deterioration from direct exposure from sunlight. If non-uv stabilized Copyright 2014 Oberon, Inc. 4/30/2014 6

7 antennas are used, it may be acceptable to mount the antennas beneath an awing or other location where direct exposure to sunlight is minimal, as shown in the figure. Installation and Accessories Oberon s indoor/outdoor polycarbonate enclosures can be easily drilled for connector and cable openings. When these openings are properly filled, the enclosure retains its NEMA 4 capability. See Oberon s accessories at This includes bulkhead connectors, antennas, cordgrips. Copyright 2014 Oberon, Inc. 4/30/2014 7