Aruba Networks AP-175DC User manual

Aruba AP-175 Outdoor Access Point
Installation Guide
0510795-01 | September 2010 1
The Aruba AP-175 is a resilient, environmentally hardened, outdoor rated, dual-radio, dual-band IEEE
802.11 a/b/g/n wireless access point. This outdoor access point is part of Aruba’s comprehensive wireless
network solution. The AP-175 works only in conjunction with an Aruba controller and each AP can be
centrally managed, configured, and upgraded through the controller.
There are three versions of the AP-175, which mainly differ in the way they receive power.
zAP-175P: PoE+ powered (802.3at)
zAP-175AC: AC powered (100 - 240 VAC)
zAP-175DC: DC powered (12 - 48 VDC)
Guide Overview
z"AP-175 Hardware Overview" on page2 provides a detailed hardware overview of the three AP-175
models.
z"Outdoor Planning and Deployment Considerations" on page5 provides key questions to ask and items
to consider when deploying an outdoor wireless network.
z"Installing the AP-175" on page9 describes the multi-step process for a successful installation and
deployment of an AP-175.
z"Safety and Regulatory Compliance" on page15 provides an overview of safety and regulatory
compliance information.
AP-175 Operations
zWireless access point (IEEE 802.11 a/b/g/n)
zWireless air monitor (IEEE 802.11 a/b/g/n)
zEnterprise mesh point
zEnterprise mesh portal
zProtocol-independent networking functionality
zAP-175P: IEEE 802.3at Power over Ethernet+ (PoE+) compatible
zAP-175AC and AP-175DC: IEEE 802.3af Power Sourcing Equipment (PSE) device
NOTE
The AP-175AC/DC can function as a Power Sourcing Equipment (PSE) device by providing power through its
Ethernet port in compliance with the IEEE 802.3af standard.
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2Aruba AP-175 Outdoor Access Point | Installation Guide
Package Contents
zAP-175 Access Point
zAP-175 Mounting Bracket
zSolar Shield
zPole Anchors x 2
zM4 x 16 bolts, flat washers, and spring washers x4 (These bolts are attached to the solar shield)
zM6 x 30 bolts, flat washers, and spring washers x2
zM4 x 12 bolt, external-tooth washer, and OT copper lug x1
zM8 x 110 bolt, flat washers, spring washers, and nuts x4
zInstallation Guide
AP-175 Hardware Overview
The following section describes the hardware features of the AP-175.
Figure 1 AP-175 Overview
NOTE
Inform your supplier if there are any incorrect, missing, or damaged parts. If possible, retain the carton, including
the original packing materials. Use these materials to repack and return the unit to the supplier if needed.
1 Antenna Interface (Radio 1) 5 Antenna Interface (Radio 0)
2 USB Console Interface 6 Antenna Interface (Radio 1)
3 Reserved (AP-175P) or
Power Interface (AP-175AC and AP-175DC)
7 Ethernet Interface (PoE)
4 Antenna Interface (Radio 0) 8 Grounding Point
2
1
3
4
8
7
65
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Aruba AP-175 Outdoor Access Point | Installation Guide 3
Antenna Interface
The AP-175 requires the use of detachable outdoor-rated antennas. Select the correct antenna type to
support the required frequency band (2.4 or 5 GHz) and the desired coverage pattern.
The AP-175 is equipped with four, female N-type antenna interfaces; two on the top of the AP and two on
the bottom. The interfaces are grouped into diversity pairs, one pair is marked R0 (Radio 0) and the other
pair marked as R1 (Radio 1). R0 supports the 5 GHz frequency band and R1 supports the 2.4 GHz radio
band.
USB Console Interface
A USB serial console port is provided for connection to a terminal, allowing direct local management. Use
the following setting to access the terminal:
Power Interface
The type of power interface on your AP-175 depends on which model you have purchased.
zAP-175P: This version does not include a power interface since it is only powered by PoE+ (802.3at).
zAP-175AC: 1x AC power connector
zAP-175DC: 1x DC power connector
Ethernet Interface
The AP-175 is equipped with a 10/100/1000Base-T Gigabit Ethernet port for wired network connectivity. On
the AP-175P, this port also supports IEEE 802.3at Power over Ethernet (PoE), accepting 48 VDC as a
standards-defined powered device (PD) from a power sourcing equipment (PSE) device, such as a PoE
midspan injector. Inversely, the AP-175AC and AP-175DC can act as a PSE device to provide IEEE802.3af
PoE power to devices connected to the Ethernet port.
Grounding Point
Always remember to protect your AP-175 by installing grounding lines. The ground connection must be
complete before connecting power to the AP-175 enclosure. Ensure that the resistance is less than 5 ohm
between the ground termination point and the grounding tier.
LED Status Indicators
The AP-175 include visual indicators for power, link, and radio status. Additionally, each radio has a four-
LED array that indicates received signal strength (RSSI).
Table 1 Console Settings
Baud Rate Data Bits Parity Stop Bits Flow Control
9600 8 None 1 None
NOTE
The RSSI LED indicators represent varying degrees in the RSSI level. The absence of a signal is indicated by no
LED response, and full signal strength is indicated when all four LEDs are active and lit.
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4Aruba AP-175 Outdoor Access Point | Installation Guide
Figure 2 LED Layout
Table 2 lists the meanings of the LEDs on the AP-175 outdoor access points.
Table 2 AP-175 LED Status Indicators
LED Function Indicator Status
P/S AP Power/Ready
Status Off No power to AP
Blinking Device booting, not ready
On Device ready
ENT LAN/Network Link
Status Off Ethernet link unavailable
On (Amber) 10/100 Mbs Ethernet link
negotiated
On (Green) 1000 Mbs Ethernet link negotiated
Blinking Traffic on Ethernet link
R0 Radio 0 Status Off Radio 0 disabled
On (Amber) Radio 0 enabled in WLAN mode
Blinking Air Monitor (AM) mode
R1 Radio 1 Status Off Radio 1disabled
On (Blue) Radio 1 enabled in WLAN mode
Blinking Air Monitor (AM) mode
RSSI (Radio 0) RSSI Level for
Radio 0 Off RSSI disabled/no signal
4 Step Progressive
Bars (Red)
25/50/75/100%
Each bar represents a progressive
increase in signal strength, with 4
bars representing maximum signal
strength (100%).
Minimum data rate: One lit LEDs
Maximum data rate: Four lit LEDs
RSSI (Radio 1) RSSI Level for
Radio 1 Off RSSI disabled/no signal
4 Step Progressive
Bars (Blue)
25/50/75/100%
Each bar represents a progressive
increase in signal strength, with 4
bars representing maximum signal
strength (100%).
Minimum data rate: One lit LEDs
Maximum data rate: Four lit LEDs
P/S ENT
RSSI for Radio 1
RSSI for Radio 0
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Aruba AP-175 Outdoor Access Point | Installation Guide 5
Outdoor Planning and Deployment Considerations
Prior to deploying an outdoor wireless network, the environment must be evaluated to plan for a successful
Aruba WLAN deployment. Successfully evaluating the environment enables the proper selection of Aruba
APs and antennas and assists in the determination of their placement for optimal RF coverage. This process
is considered WLAN or RF planning and Aruba’s system engineers can assist in the outdoor planning
process.
Scale Requirements
The potentially immense scale of outdoor deployments requires consideration of factors that may not be as
important in a typical indoor deployment:
zRange (distance): Range or distance between APs must be taken into account during the planning phase.
Available AP mounting locations are often far less flexible in an outdoor environment. Regardless of
these outdoor restrictions, the desired goal is to achieve results similar to an indoor deployment: a
“dense” RF deployment that supports advanced Aruba features, such as ARM, efficient client roaming,
and failover.
zElevation: Proper consideration and planning for elevation differences between APs (AP to AP) and AP
to Client can be critical to success. To plan for these differences in elevation, it is important to
understand the 3D coverage pattern provided by the antennas that will be deployed in the environment.
zNon-Fixed Considerations: The RF environment might change on a day to day basis. Keep non-fixed
items, such as shipping containers, vehicles, and future building construction, in mind when planning for
an outdoor deployment.
Identifying Known RF Absorbers/Reflectors/Interferences Sources
Identifying known RF absorbers/reflectors/interference sources while out in the field during the installation
phase is critical. Even though outdoor environments consist of fewer RF absorbers/reflectors/interference
sources compared to indoor environments, ensure that these sources are identified and taken into
consideration when installing and mounting an AP to its fixed outdoor location.
RF Absorbers
zCement/Concrete
zNatural Items: Trees/vegetation
zBrick
RF Reflectors
zMetal Objects: Roof-installed air-conditioning equipment, chain link fences (depending on aperture
size), other wire fences, or water pipes
RF Interference Sources
zOther 802.11a/b/g/n or broadband access equipment operating nearby
zIndustrial RF welding equipment or other Industrial, Scientific and Medical (ISM) equipment that utilizes
RF to heat or alter the physical properties of materials
zMilitary, Commercial Aviation or Weather Radar Systems
Line of Sight (Radio Path Planning)
A wireless bridge or mesh link requires a “radio line of sight” between the two antennas for optimum
performance. The concept of radio line of sight involves the area along a link through which the bulk of the
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6Aruba AP-175 Outdoor Access Point | Installation Guide
radio signal power travels. This area is known as the first Fresnel Zone of the radio link. For a radio link, no
object (including the ground) must intrude within 60% of the first Fresnel Zone.
Figure 3 illustrates the concept of a good radio line of sight.
Figure 3 Line of Sight
If there are obstacles in the radio path, there may still be a radio link but the quality and strength of the
signal will be affected. Calculating the maximum clearance from objects on a path is important as it directly
affects the decision on antenna placement and height. It is especially critical for long-distance links, where
the radio signal could easily be lost.
When planning the radio path for a wireless bridge or mesh link, consider these factors:
zAvoid any partial line of sight between the antennas
zBe cautious of trees or other foliage that may be near the path, or may grow and obstruct the path.
zBe sure there is enough clearance from buildings and that no building construction may eventually block
the path.
zFor very long distance links, the curvature of the earth (20 cm per km) may need to be considered in the
calculation of relative heights.
zCheck the topology of the land between the antennas using topographical maps, aerial photos, or even
satellite image data (software packages are available that may include this information for your area)
zAvoid a path that may incur temporary blockage due to the movement of cars, trains, or aircraft.
Antenna Height
A reliable wireless bridge or mesh link is usually best achieved by mounting the antennas at each end high
enough for a clear radio line of sight between them. The minimum height required depends on the distance
of the link, obstacles that may be in the path, topology of the terrain, and the curvature of the earth (for
links over 3 miles).
For long-distance links, the AP may have to be mounted on masts or poles that are tall enough to attain the
minimum required clearance. Use the following table to estimate the required minimum clearance above
the ground or path obstruction (for 5 GHz bridge links).
Table 3 Antenna Minimum Height and Clearance Requirements
Total Link Distance
Max Clearance for
60% of First Fresnel
Zone at 5.8 GHz
Approximate Clearance
for Earth Curvature
Total Clearance
Required at
Mid-point of Link
0.25 mile (0.402 km) 4.6 ft (1.4 m) 0.007 ft (0.002 m) 4.6 ft (1.4 m)
0.5 mile (0.805 km) 6.2 ft (1.9 m) 0.03 ft (0.010 m) 6.2 ft (1.9 m)
Radio Line of Sight
Visual Line of Sight
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Aruba AP-175 Outdoor Access Point | Installation Guide 7
Figure 4 Antenna Height and Line of Sight
A wireless bridge or mesh link is deployed to connect building A to building B, which is located three miles
(4.8 km) away. Mid-way between the two buildings is a small tree-covered hill. From the above table it can
be seen that for a three-mile link, the object clearance required at the mid-point is 5.3 m (17.4 ft). The tree
tops on the hill are at an elevation of 17 m (56 ft), so the antennas at each end of the link need to be at least
22.3 m (73 ft) high. Building A is six stories high, or 20 m (66 ft), so a 2.3 m (7.5 ft) mast or pole must be
constructed on its roof to achieve the required antenna height. Building B is only three stories high, or 9 m
(30 ft), but is located at an elevation that is 12 m (39 ft) higher than building A. To mount an antenna at the
required height on building B, a mast or pole of 1.3 m (4.3 ft) is needed.
1 mile (1.6 km) 8.9 ft (2.7 m) 0.13 ft (0.04 m) 8.9 ft (2.7 m)
2 miles (3.2 km) 12.5 ft (3.8 m) 0.5 ft (0.15 m) 13.1 ft (4.0 m)
3 miles (4.8 km) 15.4 ft (4.7 m) 1.0 ft (0.3 m) 16.4 ft (5.0 m)
4 miles (6.4 km) 17.7 ft (5.4 m) 2.0 ft (0.6 m) 19.7 ft (6.0 m)
5 miles (8 km) 20 ft (6.1 m) 3.0 ft (0.9 m) 23 ft (7.0 m)
7 miles (11.3 km) 23.6 ft (7.2 m) 6.2 ft (1.9 m) 30 ft (9.1 m)
9 miles (14.5 km) 27 ft (8.2 m) 10.2 ft (3.1 m) 37 ft (11.3 m)
12 miles (19.3 km) 30.8 ft (9.4 m) 18.0 ft (5.5 m) 49 ft (14.9 m)
15 miles (24.1 km) 34.4 ft (10.5 m) 28.0 ft (8.5 m) 62.7 ft (19.1 m)
Table 3 Antenna Minimum Height and Clearance Requirements
Total Link Distance
Max Clearance for
60% of First Fresnel
Zone at 5.8 GHz
Approximate Clearance
for Earth Curvature
Total Clearance
Required at
Mid-point of Link
NOTE
To avoid any obstruction along the path, the height of the object must be added to the minimum clearance required
for a clear radio line of sight. Consider the following simple example, illustrated in Figure 4.
AB
3 miles (4.8 km)
5.4 m
17 m
20 m
2.4 m
12 m
9m
1.4 m
Radio Line of Sight
Visual Line of Sight
!
CAUTION
Never construct a radio mast, pole, or tower near overhead power lines.
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Antenna Position and Orientation
Once the required antenna height has been determined, other factors affecting the precise position of the
wireless bridge or mesh link must be considered:
zBe sure there are no other radio antennas within 2 m (6 ft) of the wireless bridge or mesh link. These
include other WiFi radio antennas.
zPlace the wireless bridge or mesh link away from power and telephone lines.
zAvoid placing the wireless bridge or mesh link too close to any metallic reflective surfaces, such as roof-
installed air-conditioning equipment, tinted windows, wire fences, or water pipes. Ensure that there is at
least 5 feet clearance from such objects.
zThe wireless bridge or mesh link antennas at both ends of the link must be positioned with the same
polarization direction, either horizontal or vertical. Proper alignment helps to maximize throughput.
Radio Interference
The avoidance of radio interference is an important part of wireless link planning. Interference is caused by
other radio transmissions using the same or an adjacent channel frequency. You should first scan your
proposed site using a spectrum analyzer to determine if there are any strong radio signals using the 802.11a/
b/g channel frequencies. Always use a channel frequency that is furthest away from another signal.
If radio interference is still a problem with your wireless bridge or mesh link, changing the antenna
direction may improve the situation.
Weather Conditions
When planning wireless bridge or mesh links, you must take into account any extreme weather conditions
that are known to affect your location. Consider these factors:
zTemperature: The wireless bridge or mesh link is tested for normal operation in temperatures from
-. Operating in temperatures outside of this range may cause the unit to fail.
zWind Velocity: The wireless bridge or mesh link can operate in winds up to. You must consider the
known maximum wind velocity and direction at the site and be sure that any supporting structure, such
as a pole, mast, or tower, is built to withstand this force.
zLightning: Rain: The wireless bridge or mesh link is weatherproofed against rain. However, it is
recommended to apply weatherproof sealing tape around the Ethernet port and antenna connectors for
extra protection. If moisture enters a connector, it may cause a degradation in performance or even a
complete failure of the link.
zSnow and Ice: Falling snow, like rain, has no significant effect on the radio signal. However, a buildup of
snow or ice on antennas may cause the link to fail. In this case, the snow or ice has to be cleared from
the antennas to restore operation of the link.
NOTE
Local regulations may limit or prevent construction of a high radio mast or tower. If your wireless bridge or mesh link
requires a high radio mast or tower, consult a professional contractor for advice.
!
CAUTION
An Aruba Lightning Arrestor, AP-LAR-1, must be installed on each antenna port for protection against lightning
induced surges. Failure to use an AP-LAR-1 can void the warranty of an Aruba outdoor AP model and renders the
AP susceptible to failure from lightning induced surges
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Aruba AP-175 Outdoor Access Point | Installation Guide 9
Ethernet Cabling
When a suitable antenna location has been determined, you must plan a cable route from the wireless
bridge or mesh link outdoors to a suitable power and/or network source.
Consider these points:
zThe Ethernet cable length should never be longer than 90 m (295 ft).
zDetermine a building entry point for the cable (if applicable).
zDetermine if conduits, bracing, or other structures are required for safety or protection of the cable.
zFor lightning protection at the power injector end of the cable, consider using a lightning arrestor
immediately before the cable enters the building
Grounding
It is important that the wireless bridge or mesh link, cables, and any supporting structures are properly
grounded. Each AP-175 access point includes a grounding screw for attaching a ground wire. Be sure that
grounding is available and that it meets local and national electrical codes. Ground the access point first
using the external ground stud on the unit before making any other connection.
Installing the AP-175
The AP-175 can be installed on a wall or attached to a pole. The following section describes how to attach
the necessary hardware to the AP and how to mount the AP in the selected location.
Selecting the Installation Site
zThe site should be located within at least a 60% range of the 1st fresnel zone without obstacles to provide
line of sight (LOS) transmission, increase coverage capacity, and minimize the number of necessary
sites.
zIf no LOS is secured, areas in non-line-of-sight (NLOS) areas could be covered as well, but the distance
of coverage and area of coverage are decreased; more sites are needed to provide coverage for same
area than in the LOS scenario.
zInterference must be considered in site selection. The new site should avoid known interference, unless
the interference is controllable.
zKeep the AP-175 away from places that are susceptible to high temperature, dust, harmful gas,
inflammable, explosive, electromagnetic interference (high power radar, radio station and transformer),
unstable voltage, heavy vibration, or loud noise. In engineering design, the site should be selected
according to the network planning and technical requirements of communications equipment, as well as
the considerations such as climate, hydrology, geology, earthquake, electric power, and transportation.
Installing the AP-175 on a Pole
1. Attach the AP-175 on the mounting bracket using the two M6 x30 bolts (with flat and spring washers) on
each side of the mounting bracket.
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10 Aruba AP-175 Outdoor Access Point | Installation Guide
Figure 5 Attaching the mounting bracket to the AP
2. Attach the mounting bracket (with AP-175) on the pole using four M8 x110 bolts (with flat washers,
spring washers and nuts) and the pair of pole anchors.
Figure 6 Attaching the mounting bracket to the pole
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