Knowledge Net Cisco Aironet Wireless Site Survey (Cawss) 4.0 Student Guide

8/6/2019 Knowledge Net Cisco Aironet Wireless Site Survey (Cawss) 4.0 Student Guide

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CAWSS

Cisco Aironet Wireless

Site Survey

Version 4.0

Student Guide

Text Part Number: 67-1801-01


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CopyrightM 2002, Cisco Systems, Inc. All rights reserved.

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Table of ContentsCourse Introduction 1

Overview 1Course Goal and Objectives 1Course Outline 2

Learner Skills and Knowledge 3Learner Responsibilities 4General Administration 5Course Flow 6Icons and Symbols 7Learner Introductions 8Wireless Networking Overview 9Customer Assistance 10WLAN Topologies 11

Impact of WLAN Applications and Design on a Site Survey 1-1

Overview 1-1Module Objectives 1-1

Module Outline 1-2WLAN Applications 1-3WLAN Design 1-7Retail 1-12Warehousing and Manufacturing 1-18Healthcare 1-22Hotels and Hospitality 1-26Hot Spots 1-30Education 1-32Offices 1-34Transportation 1-36Government 1-39Summary 1-44

Review Questions 1-45Manual Site Survey Tools 2-1

Overview 2-1Module Objectives 2-1Module Outline 2-2

Access Point Selection 2-3Site Survey Equipment 2-5Summary 2-16Review Questions 2-17

Manual Site Survey Utilities and Techniques 3-1

Overview 3-1

Module Objectives 3-1Module Outline 3-2

Preparation 3-3Indoor Site Survey Concepts 3-4Software Tools 3-20Summary 3-45Review Questions 3-46


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ii Cisco Aironet Wireless Site Survey (CAWSS) v4.0 Copyright 2004, Cisco Systems, Inc.

Using the AirMagnet Site Survey Tool for a Manual Survey 4-1


DSA Coverage 4-3AirMagnet Site Survey Tool 4-11Manual Survey Situations and Obstacles 4-28Summary 4-39Review Questions 4-40

Assisted Site Survey Techniques 5


Introduction to Assisted Site Survey Technologies 5-3Required Cisco Products 5-6Density Testing 5-8Access Point Radio Scans 5-11Client Walkabout 5-20Final Testing 5-28

Displaying a Configured Radio Parameters Report (11b) 5-32Displaying a Path Loss Between Managed APs Report (11b) 5-32Displaying a Channel Loading Report (11b) 5-33

Summary 5-36Review Questions 5-37

WLAN Design Considerations 6-1


LAN Infrastructure 6-3Cables and Connectors 6-6

Plenum 6-10Firewalls 6-13Risers 6-15Mounting 6-16Securing the Access Point 6-20Splitters 6-24NEMA Enclosures 6-27Summary 6-31Review Questions 6-32

Documentation 7-1

Overview 7-1Module Objectives 7-1

Module Outline 7-2Site Survey Preassessment Form 7-3Site Survey Report 7-5Summary 7-13Review Questions 7-14


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CAWSS

Course Introduction

OverviewCisco Aironet Wireless Site Survey (CAWSS) v4.0 teaches how to perform site surveys for

wireless LAN (WLAN) solution implementations. Presentation material will explore WLAN

applications in specific markets, WLAN topologies and design concerns, essential equipment,

access point configuration, and site survey techniques. The class will feature instructor-led

presentations highlighting both manual and assisted site survey techniques. Successful

completion of the Cisco Aironet Wireless LAN Fundamentals (AWLF) course is a prerequisite

to taking this course.

Course Goal and Objectives

This section describes the course goal and objectives.

2004 Cisco Systems, Inc. All rights reserved. CAWSS 4.0 #-3

Course Goal

To guide the learner to performmanual and assisted site surveysfor the wireless LANenvironment.

Cisco Aironet Wireless Site Survey


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2 Cisco Aironet Wireless Site Survey (CAWSS) v4.0 Copyright 2004, Cisco Systems, Inc.

Upon completing this course, you will be able to meet these objectives:

Describe the requirements for a manual and an automated site survey

Generate proper documentation of site survey findings, including being able to develop a

complete WLAN solution with staging and installation services, and all necessary

equipment

Describe installation techniques and WLAN infrastructure issues

Course Outline

The outline lists the modules included in this course.


Course Outline

Impact of WLAN Applications and Design on aSite Survey

Manual Site Survey Tools Manual Site Survey Utilities and Techniques

Using the AirMagnet Site Survey Tool for aManual Survey

Assisted Site Survey Techniques

WLAN Design Considerations

Documentation


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Copyright 2004, Cisco Systems, Inc. Course Introduction 3

Learner Skills and KnowledgeThis topic lists the course prerequisites.


Prerequisite Learner Skillsand Knowledge

AWLFCAWSS v4.0

To benefit fully from this course, you must have these prerequisite skills and knowledge:

Knowledge of fundamental networking components and terminology

Knowledge of the Open Systems Interconnection (OSI) reference model

Knowledge of basic LAN components and functions

Successful completion of the Cisco Aironet Wireless LAN Fundamentals (AWLF) course


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Learner ResponsibilitiesThis topic discusses the responsibilities of the learners.


Learner Responsibilities

Completeprerequisites

Ask questions

Provide feedback

To take full advantage of the information presented in this course, you must have completed the

prerequisite requirements.

In class, you are expected to participate in all lesson exercises and assessments.

In addition, you are encouraged to ask any questions relevant to the course materials.

If you have pertinent information or questions concerning future Cisco product releases and

product features, please discuss these topics during breaks or after class. The instructor will

answer your questions or direct you to an appropriate information source.


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Course FlowThis topic covers the suggested flow of the course materials.


Course Flow

Course Introduction

Manual Site Survey Tools

Lunch

AM

P

M

Day 1

Impact of WLAN Applications andDesign on a Site Survey

Using the AirMagnet Site Survey Tool for aManual Survey

Assisted Site Survey Techniques

Manual Site Survey Utilities and Techniques

WLAN Design Considerations

Documentation

The schedule reflects the recommended structure for this course. This structure allows enough

time for the instructor to present the course information. The exact timing of the subject

materials depends on the pace of your specific class.


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Icons and SymbolsThis topic shows the Cisco icons and symbols used in this course.


Icons and Symbols

Ethernet

Client

AccessPoint

Handheld

Device

PC Card

Tablet

Wireless

Connectivity

Scanner

Wireless

Bridge

Dual-Mode

AccessPoint

PC

Laptop

Mobile

Access

Router

BBSM

Small Hub

(10BASE-T Hub)

100BASE-T

Hub

Router

Wireless LAN

Solution Engine


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Learner IntroductionsThis is the point in the course where you introduce yourself.


Learner Introductions

Your name

Yourcompany

Skills andknowledge

Brief history

Objective

Prepare to share the following information:

Your name

Your company

If you have most or all of the prerequisite skills

A profile of your experience

What you would like to learn from this course


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Wireless Networking OverviewThis topic provides an overview of wireless networking.


Why Would I Want a Site Survey?

Many people think that there is a science behind installing a wireless LAN (WLAN). While

there is certainly a lot of science behind the technology, performing a site survey may be

thought of more as an art.

As a WLAN site survey engineer, you will have to be knowledgeable about both the wireless

equipment that you are installing and the wired equipment with which you may be interfacing.

To overcome limitations that are presented by the facility, as well as by the equipment, a good

site engineer will be able to thinkoutside of the box.

So why is a site survey important? Before installing WLAN access points, you need to know a

number of things about the facility of your customer. A good site survey will help you

determine the following:

Feasibility of the desired coverage

Radio frequency (RF) interference

Wired connectivity limitations

A site survey will allow the customer to properly install the WLAN and have consistent,

reliable wireless access.


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Customer AssistanceThis topic identifies how a site survey will help the customer determine how many access

points will be needed throughout a facility to provide the desired coverage.


Customer Assistance

Howmany?

Where

?Throughput?

RFWL

AN

Coverage

WiredAve.

Wireles

s Blvd.

A site survey can also help determine the placement of those access points and detail the

necessary information for installation.

This class will provide you with lists of all the necessary tools, and the knowledge that is

needed, to perform a site survey. While exposure to the tools and knowledge is certainly the

place to start, it must be combined with experience. The more experienced the site survey

engineer, the better the survey.


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WLAN TopologiesThis topic identifies some of the topology information, standards, and components that a site

survey engineer might need to be aware of when performing a site survey.


WLAN Topologies

Limitations of the wirednetwork

Knowledge of wired LANsallows the following:

Creativity in your WLANdesign

Superior design for thecustomer

Know wired and wirelessalternatives

Sometimes the topology of the WLAN will be dictated by the layout of the wired LAN to

which the WLAN will be connected. If wired connectivity is available only along one side of a

100,000 square-foot (9,290 square meters) warehouse, for example, the distance limitations of a

Category 5 cable run (328 feet, or 100 m) may not be sufficient to reach the recommended

location of the access point.

This is where the site survey engineer will have to be creative. There are many possible

solutions: a wireless hop using a repeater talking back to a wired access point, a repeater or a

hub to extend the Category 5 cable run, or installation of a fiber link to provide connectivity on

the other side of the warehouse.

As a site survey engineer, you are responsible not only for finding the best locations for the

access points but also for finding ways to connect the access points to the wired network.


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WLAN Topologies (Cont.)

Understand wired

networking productsand their functionality

Hubs

Switches

Routers

Alternative media

It is therefore crucial that the engineer have an understanding of wired networks. This

understanding should cover wired LAN topologies, standards, and components.

The understanding of components must include the functionality of repeaters, hubs, switches,

and routers. Attaching an access point to a hub has very different implications from attaching

an access point to a switch, for example.

By understanding the components, you will be able to design a WLAN that meets all

specifications for the existing wired LAN topology. You must also be aware of the media being

installed and be sure that the WLAN that you design will meet all requirements for that media

type, as well as state and local building codes.


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Module 1

Impact of WLAN Applicationsand Design on a Site Survey

OverviewThis module explores the various types of wireless LAN (WLAN) sites that site survey

engineers need to survey in order to optimize coverage, and the special considerations that each

site type presents.

Module Objectives

Upon completing this module, you will be able to complete the objectives shown in the figure.

2004 Cisco Systems, Inc. All rights reserved. CAWSS 4.04-2

Objectives

Obtain information necessary to perform the sitesurvey

Determine customer needs as part of preparationfor designing a wireless LAN

Identify the type of site survey to be performed priorto arrival at the customer site

Describe the site situation and any possibleobstacles that may impede the site survey


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1-2 Cisco Aironet Wireless Site Survey (CAWSS) v4.0 Copyright 2004, Cisco Systems, Inc.

Module Outline

The outline lists the components of this module.


Outline

Overview

WLAN Applications

WLAN Design

Retail

Warehousing and Manufacturing

Healthcare

Hotels and Hospitality

Hot Spots

Education

Offices

Transportation Government

Summary

Review Questions


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Copyright 2004, Cisco Systems, Inc. Impact of WLAN Applications and Designs on a Site Survey 1-3

WLAN ApplicationsAs wireless technology continues to evolve, data rates and interference immunity are

improving. These improvements make wireless a viable technology for use in most

applications. This topic discusses WLAN applications.


WLAN Applications

As the acceptance of wireless technologies continues to grow, the advantages of a mobile

workforce and a flexible network become more apparent to network managers.


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Be Prepared

Come prepared to ask and answer questions.

Instill a sense of confidence in the customer.

Bring proper equipment.

Site survey engineers need to be aware of specific issues that surround many of the industries

that require WLAN services. IT managers, upper management, or board members often want

to discuss the implementation of wireless equipment in their facility.

The customer wants to know that the WLAN installation will provide a reliable link to the

network for wireless clients. Site survey engineers can expect that certain issues have already

been resolved with a salesperson or site engineer prior to their arrival, but this is not always the

case. Site survey engineers must be aware of all potential concerns so that they can present an

informed and confident image when meeting with the customer. Site survey engineers who

appear incompetent or misinformed may cause the survey or even the implementation to be

cancelled altogether. Having the proper equipment (IEEE 802.11a, 802.11b, or 802.11g) onhand is one way that the site survey engineer can foster confidence.


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RFYesterday and Today

Early adopters of RF technology

Vertical markets

Mobility

Today

Vertical and horizontal markets

Movability

Standards and throughput

Early adopters of wireless technology were in vertical markets such as education and logistics.

These users were more concerned with mobility than with standards or data throughput.

Users today are moving into more horizontal markets where mobility may be less of a concern

than interoperability and throughput. With the Cisco Aironet products, users do not have to

sacrifice mobility and roaming to gain throughput and interoperability.


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5 GHz vs. 2.4 GHz

Both technologies will

work in these markets.

XXFinancial

Institutions

XXRetail

XXXEnterprise

Office

XTransportation

XWarehousing

XXXHigher

Education

XXXHealthcare

XXManufacturing

XXHospitality

802.11a802.11g802.11b

Popular Choices

The figure here shows popular application choices for the various technologies. Depending on

the application, all three technologies function very well in vertical markets. For instance,

warehousing is generally record transaction updating, and therefore the data rate is not the

highest concern; instead, the range is of chief interest. On the other hand, the patient areas of a

hospital may require high data rates for file transfers of X-ray images.

The following slides will address key issues that the site survey engineer should consider when

deploying wireless technology. IEEE 802.11a uses a 5-GHz radio. 802.11b and 802.11g use

2.4-GHz radios.


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WLAN DesignThere are several factors that are important in a WLAN design. This topic discusses some of

those factors.


Wireless LAN Design Concerns

Client type and mobility

Cards

PCM, LMC, PCI

Repeaters and workgroupbridges

Third-party 802.11 devices

Bar code scanners,telephony, Wi-Fi devices

One of the factors affecting WLAN design may be the particular type of client that the

customer will be using. PC cards or embedded radios in laptops provide mobility to internal

staff and easy connectivity for remote users when they are in the facility. Peripheral Component

Interconnect (PCI) cards give users the freedom to occasionally move desktop PCs without

having to worry about installing cable. A repeater or a workgroup bridge provides connectivity

to remote users without standard leased lines or the need to run fiber. Some customers maywant to use data collection terminals, while others want 802.11 phones.

Most sites will use a combination of these options. A review of the specifications and

compatibility information is needed from all devices to ensure functionality.


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Customer Applications

Know what the customer needs from the

wireless LAN

E-mail and web users have different needsthan a CAD developer

Client-server

Thin client

The site survey engineer must be aware of the applications that will be used in the wireless

network. Someone who performs the occasional file transfer and checks e-mail has very

different needs from someone using a computer-aided design (CAD) application across the

network.

Many offices today use a model with frequently used applications such as e-mail and internal

ordering software loaded on each terminal. Other companies are moving to thin clients. They

may have much greater bandwidth requirements. This type of setup requires a very reliable

connection to the network, because an interruption of network service leaves the user helpless.


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Wireless LAN Design

Pools of higher data rate coverage

Stationary vs. mobile54

Mbps

11 Mbps

In an environment where the PCs remain stationary most of the time, providing wireless

connectivity is a fairly easy task. For installations of this type, users typically need pools of

coverage and are not overly concerned with their link speed while moving.

Many customers do not fully understand the equipment that will be installed or what to expect.

Some people believe that it will be a full 11- or 54-Mbps link for every user. Some people

question the reliability of the radio frequency (RF) link and intend to use the wireless link on a

limited basis. The truth is that most users will fall somewhere between these two.


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Rate Shifting

Survey performed at

each data rate?

Coverage cell foreach rate mapped

Higher rates shiftto proper areas

Lower rates overlap andfrequency

There will be pools of coverage at each data rate. If the customer wants to provide certain

areas with coverage at a specific data rate, multiple site surveys may be required. The Cisco

Aironet Site Survey Utility surveys are at a given rate, and that rate does not shift.

The higher data rate cells will need to be mapped out so they can be shifted to the proper areas.

The lower data rate coverage cells will also need to be mapped out with an eye on the overlap

of these cells and on frequency selection. An overlap of approximately 15 percent is required

for smooth, reliable handoffs between access points.

Before surveying, knowing how much throughput that the users require will help in

determining where the access points will need to be placed.


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RetailOne of the early adopters of wireless technology was the retail industry. This topic discusses

wireless in the retail industry.


Wireless in Retail

Early users of wirelesstechnology

Wireless use for real-time applications

Use of wirelesstechnology for specialevents

Use of WLANs for voiceand paging

Hot spots in retail stores

Data collection devices are extremely valuable tools for checking stock, receiving, and point of

sale. Wireless data collection devices offer the retail industry real-time updates to their

databases and the ability to place registers and printers throughout the store for special events

(such as a sidewalk or tent sale) without having to worry about cabling.

Recently there have been new kinds of wireless devices and services placed in the retail stores.

The most popular are as follows:

Wireless 802.11 phones

Wireless kioskshelp customers to scan and validate prices

Wireless multimedia stations or cartsprovide marketing and advertising information to

retail customers

Wi-Fi hot spotsWi-Fi access to the Internet in certain locations in the stores

These wireless services and devices are additional overhead to the WLAN in the retail industry.

They can be difficult to plan for because the wireless use is coming from the retail customers

and not from the retail employees.

Additional customer services may require a higher throughput RF technology such as 802.11a

or 802.11g. In this case, a site survey would need to be performed to accommodate data

collection devices using 802.11b and 802.11a or 802.11g devices.


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Wireless in Retail (Cont.)

Uneven use of wirelessduring retail open and offhours

Different wirelessapplications during differentretail hours

Heavy wireless LAN usageduring inventory hours

Heavy WLAN overhead by802.11 voice devices

Special coveragerequirements on loadingdocs, back rooms andtrailers, and hot spot usage

Retail implementations often involve a large number of users sending data frequently. These

same stores are likely to conduct their inventory at night. This situation can mean that there will

be an uneven WLAN use during the normal store hours and night hours.

During normal business hours, the WLAN may be taxed more with voice devices that place

huge overhead on the 11-Mbps access points, because most voice devices operate in 2.4-GHz

range. Typically, one Cisco access point can handle seven to eight concurrent voice

conversations. If data collection terminals need to operate at the same time and in the same

locations, the design and survey should be performed accordingly.

When the inventory crew comes in at night, the customer expects that the WLAN will be able

to handle the demand. The design needs to take several factors into consideration: how ofteninventory is conducted, how many data collection devices are used, the specific locations, and

what the requirements are for their particular applications. It is also important to know if

wireless phones will be used at the same time that the inventory is being conducted.

It is also important to know if coverage on the loading docks or inside the trucks at the loading

docks is required. Depending on the WLAN design, there may be enough RF coverage

extending to the outside of the buildings to accommodate this need, but it is recommended that

it be factored into the design.


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Most data collection devicesdo not support 802.11a or802.11g yet.

Some devices require only 2to 11 Mbps.

Will data collection devicesbe the only clients usingWLAN?

Survey for 11-Mbpscoveragemost used on DCdevices.

Some devices can rate shift.

If the customer intends to use data collection devices exclusively, this situation will change

how the survey is performed. Most data collection devices today do not support 802.11a or

802.11g yet, and operate only at the 2- to 11-Mbps range. Most data collection applications do

not require 54 Mbps.

If the customer is using an 11-Mbps data collection device with no intention of adding other

wireless clients or services that may operate in the range of 11- to 54-Mbps, then the site survey

should be performed at 11 Mbps. All areas where the data collection devices will be used must

have at least a 2-Mbps link if rate shifting is supported on the devices.

Some data collection devices have the ability to rate shift from 54 to 48 to 36 to 24 to 18 to 11to 5.5 to 2 to 1 Mbps for 802.11g or from 54 to 48 to 36 to 24 to 18 to 12 to 9 to 6 for 802.11a.

It is important to know what the devices of the customer are, what abilities these devices have,

and how the devices are to be used.

Different data rates provide different coverage areas; the lower the data rate, the larger the

coverage area will become, and the adjacent access point overlap may increase significantly.


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Multiple workers

sending lots ofinformation

Needs of theapplication

Evaluate theapplication

Retail sites may have areas with large numbers of very busy users, such as a receiving area. As

equipment is unloaded from trailers, it is unboxed and bar codes are scanned in rapid

succession, sending large packets containing a lot of data. If there are 20 to 30 users scanning

bar codes and entering keystrokes in rapid succession, a single access point may not be enough.

As an example, if all of the data collection devices are communicating at 11 Mbps, realistically,

the access point is operating at only 11 Mbps. This is not to say that the access point is limited

to 11 Mbps, but that there are no communications happening at data rates above 11 Mbps.

While the 11-to-54-Mbps connection might be sufficient to handle the 20 to 30 users, the single

11-Mbps access point may be a bottleneck. The packet size of the application, the number of

users, and the frequency with which the users will be transmitting data via the WLAN need to

be assessed to determine if extra access points are needed in this area. If extra access points areneeded, then access points must be configured on nonadjacent channels.


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Source of interferencein retail

Inventory items

2.4- and 5-GHz equipment

Colocated stores usingWLANs

Colocated hot spots

Locate access points awayfrom these items on theshowroom floor.

Consider differentapproaches to lower

interference.

Other concerns within the retail industry include the close proximity of the store to other RF

devices. Some stores may stock and demo RF devices in their store, including satellite systems,

baby monitors, or cordless phones. Many of these may be operating in 2.4-GHz range and some

in the 5-GHz range. It is not recommended that access points be installed next to this type of

equipment because they typically have a higher transmitter power.

Some retail stores use internal cordless phone systems. Ideally, they should use a system that

operates in a different RF spectrum. There are phones that operate at 900 MHz, 2.4 GHz, and 5

GHz. It is far less expensive to replace a few cordless phones than to try and design a WLAN

around an existing phone system so that it does not interfere with it.

Retail stores may also be located in malls or strip malls where there may be other users

operating 2.4-GHz equipment or even a hot spot service provider operating on the same RF

spectrum. The systems integrators and surrounding store managers can provide information

about their systems or hot spot services. Site surveys should not be performed without this

information. Optimally, the stores can separate their signals by channel, service set identifier

(SSID), and so on.


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Warehousing and ManufacturingWarehouse and manufacturing implementations present many obstacles. This topic discusses

the various problems with warehouse and manufacturing implementations.


Warehousing

Multiple users

Large coverage areas

Transaction-orientedapplications

Highly mobile users

Varied wireless

devices

Warehouse implementations present many of the same problems as the retail market. There

may be a limited number of users during the day, but when a shipment comes in, or if multiple

shipments come in at the same time, many or all users may be operating at the same time.

Coverage areas are generally large, subject to a lot of multipath or RF interference because of

concrete floors, metal roofing, and metal shelving. Cell size is more important than data rates

because warehouse applications are generally transaction-driven with small packet sizes. Cell

coverage overlap needs to be from 10 to 15 percent. The usage is not that high, but the users are

highly mobile and must roam often.

2.4 GHz is almost always the choice. Diversity antennas are often useful in areas with higher

multipath interference and utilization. Medium-gain antennas are generally the best solution.

There is no way of determining the distance of a signal without knowing the type of inventory.

Different types of stock will either absorb or reflect the radio frequency.

Inventory that reflects an RF signal includes metal and lead-based paint. Inventory that absorbs

an RF signal includes water, wood, plants and trees, paper and boxes, non-lead-based paint, pet

food, and cat litter.


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Warehousing (Cont.)

Talk with warehouse

personnel aboutinventory levels.

Consult more thanone individual.

The site survey engineer should try to talk with personnel who work in the warehouse. A

forklift driver may actually have a more accurate opinion of current stock levels. These levels

can vary on a monthly, weekly, or daily basis depending upon the time of year and the

business. The site survey engineer should also talk with the warehouse manager about when

stock levels are at their highest and try to perform the site survey during this period. A

warehouse at 50 percent stocking level has a very different RF footprint than what the same

warehouse has at 100 percent.

Making inquiries of numerous people will provide more accurate details about stock levels. The

site survey engineer should talk with as many people as possible throughout the warehouse,

inquiring about stock levels and periods of high usage. If this information gathering is not

possible, the plan should compensate for the potential increase in stock. Otherwise, thereshould be a statement in the documentation that indemnifies the engineer if the physical layout

of the site changes, to include stock levels.


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Warehousing (Cont.)

Keep in mind while performing the survey:

Exposure to the elements

Freezers

Weatherproof enclosures

Shelving

Antenna mounting

Forklift paths

Warehouses or distribution centers are typically dirty and have maximum exposure to the

elements. Here are a few questions to keep in mind while performing the survey:

Will the access points need to be mounted in sealed boxes for protection? The environment

will help determine if a sealed box is needed.

Are there freezer areas (which are difficult to cover and hard on electrical equipment)?

If the environment exceeds the limitations of the access point, will you need heated

enclosures?

How much clearance exists above the shelving? Will it be sufficient to mount an antenna?Or will a forklift or the inventory that the forklift is loading onto a top shelf crush the

antenna?

It is important to consider the performance of the various wireless devices. Warehouses often

have wireless devices from several vendors or for different applications. The access point must

be able to interface with the various devices and provide coverage for all.


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Manufacturing

The applications are generally transaction-oriented.

Throughput is not the primary concern.

Surveying should be done with the sameconcerns as warehousing.

Manufacturing embraces WLAN solutions because it integrates very nicely into its just in

time environment. WLAN devices are used for assembly line inventory accounting, RF-

controlled robots, quality control, network connectivity, and warehouse management. Forklifts

can be equipped with wireless data collection devices, and handheld devices can be given to

mobile workers.

Manufacturing presents some issues that the site survey engineer must consider:

High ceilings: Caution should be used when omnidirectional antennas are installed higher

than 40 feet. This height will cause data collection devices underneath the antennas to lose

the signal.

Forklift paths: Forklifts can knock down equipment when they are moving stock.

Machines: Conflicting frequencies can be generated by machines.

Chain-link fence: This kind of fence blocks and grounds RF signals (such as in the tool

room).

Conveyor belts: The metal in the belts causes multipathing.

Robots: Unmanned robots follow tracks in the floor to deliver products throughout the

plant.

Racking: Racking can affect WLAN devices depending on how the racks are oriented and

what the racking holds.

Unions: Respectfully find out what can and cannot be done by the site survey engineer.

System redundancy: Hot Standby might need to be deployed to protect mission critical

areas.


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HealthcareHealthcare site surveys are some of the most restricting, time-consuming, and difficult site

surveys to be performed. The primary reason for this difficulty is that almost every hospital is a

multistory building with numerous small rooms. This topic discusses site surveys in hospitals.


3-D Site Survey

Watch out for the 2-D trap.

Expect lots of access points.

Make use of nonoverlappingchannels.

Look for trauma or X-ray

rooms with lead-lined walls. Elevators represent potentialdead zones.

Because of the multifloor configuration of many sites, the survey must be thought of as a three-

dimensional (3-D) survey. While marking site maps (which are two-dimensional), many

engineers start to think of the survey as two-dimensional. The RF signal needs to be thought of

as three-dimensional, covering not only the floor on which the access points are mounted butalso the floors above and below.

A hospital is a good example of a 3-D site survey. The need to think of a hospital site survey as

3-D is especially true in hospitals, because they typically require a large number of access

points. Because there are only three nonoverlapping channels, special care needs to be taken

when locating access points so that interference from other access points is eliminated as much

as possible. Take advantage of the nonoverlapping channels when possible.

Watch out for trauma and X-ray areas where the walls may be lead-lined. Also locate elevator

shafts, which are usually colocated in hospitals and may be detrimental to the RF signal.


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Healthcare

Multiple floors

Numerous rooms

Numerous and quitediverse applications

Multiple vendors ofWLAN equipment

Certain applications such as portable X-ray and ultrasound devices may require a lot of

bandwidth. These applications would require 802.11a or 802.11g data rates and are generally

used in areas of the hospital that are the least friendly to RF signal propagation. These same

areas of the hospital mostly have an overlay of RF networks. Those networks may be on

different frequency bands but are generally using one of the three industrial, scientific, and

medical (ISM) bands.

Beyond this, there are a number of concerns that the RF devices may interfere with the wireless

equipment, or vice versa, and hospital administrators will want assurances that there will not be

interference. It is important to remember that portable hospital monitoring equipment may have

embedded WLAN radios.


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Healthcare (Cont.)

Testing performed by

biomedical department

Cisco Aironet Access Points

Industrial, scientific, andmedical

FCC compliance

FCC safety

Hospital equipment shouldbe built to a standard toavoid RF interference

Before any hospital floor space is surveyed, it is imperative that the site survey engineer

determine that deploying 2.4-GHz and 5-GHz equipment will not interfere with life support

equipment. This information is obtained by using the hospital biomedical department to certify

that the equipment will not cause life-threatening problems.

The 2.4-GHz and 5-GHz radios are Federal Communications Commission (FCC)-compliant

and are part of the ISM unlicensed band.


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Healthcare (Cont.)

Hospitals house sick peoplebe preparedto deal with this.

Be sensitive to areas where you may not bewanted or allowed.

Do not abuse privileges.

Hospital surveys also require engineers with a certain amount of mettle. It is not unheard of to

have to survey the intensive care unit, infant intensive care unit, birthing unit, surgery unit, burn

victim unit, morgue, emergency room, or trauma unit. The sight of patients in a condition that

requires them to be in one of these units sometimes has a very profound effect on individuals.

The engineer needs to be able to handle all of this with grace. More than one engineer has been

caught in the trauma unit when a critically injured patient is being wheeled in.

Most hospitals cannot afford to have an individual escort the engineer all day while they

perform the survey. Engineers are usually given a visitor badge and a tour, where they are

shown specific areas where they will not be allowed without an escort, if at all. In the surgery

area of the hospital, the engineer may be required to wear a gown to survey the area. Usually,

engineers are not allowed in the psychiatric ward or the criminal ward without a security escort.


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Hotels and HospitalityHotels are much like hospitals in their building construction and configuration (multifloor with

many rooms). Hotels have started using WLANs to support data collection devices for taking

inventory of things such as minibars. However, with the popularity of the Internet and the

demand for Internet connectivity, WLANs are being installed into more and more hotels to

provide Internet connectivity for hotel guests. This topic discusses the specific site survey

concerns presented by hotels.


Hotels and Hospitality

Multifloor construction

Numerous rooms

Throughput

Fewer users peraccess point

Multiple buildingmaterials

Hotel

Beyond requiring the engineer to look at the survey three-dimensionally, hotels present suchconcerns as data rates and throughput, and security.

The high number of walls (separating guest rooms) decreases the range of access points and

thus increases the need for more access points.

Hotels want to offer their guests fast, reliable Internet access, which means fewer users per

access point. In addition, hotels historically have a lower density as rooms geographically

distribute users fairly well, which helps with the placement of access points.


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Hotels and Hospitality (Cont.)

Physical security

Network security Billing

Aesthetics

Older hotel buildings

Hard-cap ceiling

Poured concrete walls

Newer hotels have drop-tile ceilings

Most business travelers want to know that the data that they are sending is secure, and the hotel

wants to know that not just anyone with an 802.11 card can access its network.

Hotels often house restaurants, and retail and convention areas, which makes them fairly public

places and thus susceptible to theft and vandalism. Proper securing of the access points to

ceilings or walls, in addition to hiding them above the ceiling, are good practices.

One solution to the security issue is Wired Equivalent Privacy (WEP) encryption. Cisco

Aironet recommends using at least 128 bits. Other methods of security available with Cisco

Aironet include a RADIUS server or Building Broadband Service Manager (BBSM). The

overhead that WEP adds is minimal (about 3 percent). This relative lack of overhead means

that there is no need to survey using WEP keys. If the customer decides to implement WEPduring installation, it will have no effect on the survey. Another solution is Cisco Lightweight

Extensible Authentication Protocol (LEAP) authentication (based on 802.1x standards). Just as

with WEP, there is no need to implement LEAP during the survey. These two solutions do,

however, require additional directions to customers and possible back-end work on the part of

IT (creating new user accounts and so on) or both.

Hotels will also have many of the same concerns as hospitals regarding aesthetics. Depending

on the age of the hotel, building construction may become a factor. Newer hotels will have

drop-tile ceilings in hallways but rarely in guest rooms. Older hotels will often have hard-cap

ceilings. These are ceilings that are poured concrete. There is no real, effective way to run cable

across a hard-cap ceiling. Keep this fact in mind when you are deciding where to mount access

points. Older hotels may also have walls of poured concrete instead of Sheetrock. This situation

presents the same problems as hard-cap ceilings. A solution is to use Cisco LRE (Long-ReachEthernet) over the existing phone lines; Cisco LRE makes use of the phone lines for high-speed

Ethernet.


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Possible interference with hotel infrastructure

wireless Cleaning services, maintenance, security

Possible multiple providers in separate locationsof hotel

Rooms, convention center, retail areas

Wireless has become increasingly popular as a means of streamlining hotel operations, for

everything from guest services (check-in, concierge) to house cleaning and maintenance.

Handheld devices and IP phones require their own infrastructure. If the public access provider

is willing, the use of VLANs can allow single access points to support both public and private

usage. Otherwise, overlay networks are required.

Hotels are no longer simply places for travelers to spend the night. Increasingly, they have

everything that travelers need during their stay: convention and conference services, retail

shops, and, of course, restaurants. These locations may have their own contracts and providers,

causing possible interference between networks.


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Hotel conference centers

Sporadic usage High density for key shows

Differing security requirements for individualshows

By their very definition, convention and conference centers do not have continual usage and

often provide fewer access points. When the convention or conference is in use, however, there

is the potential for a huge number of users in a small area, a situation that requires a high

number of access points providing high throughput per user.

The convention center network usually needs to be isolated and available for numerous changes

and additions. Each incoming convention requires different types of security (WEP, 802.1x,

open, and so on), as well as front-end servers and other services available to attendees. This

location should not be connected to the hotel network because it could provide a source for

viruses and bring instability to the hotel network.


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EducationThe primary concern when you are implementing a WLAN in an educational facility is the

students. More and more WLANs are being installed in grade schools, middle schools, and high

schools. Students at this age have a tendency to be curious and sometimes destructive. This

topic discusses the factors involved in an educational site survey.


Education

Children can be

Curious

Destructive

Antennas and access points should be hidden or

enclosed to avoid damage.

An antenna mounted to the ceiling in a hallway will likely not stay mounted for long. Access

points have flashing lights that seem to draw in curious children.

Educational facilities, more so than any other implementation, must have the equipment

installed in the most inconspicuous manner possible. This level of precaution is the only way to

ensure that the equipment will be safe. However, there are other security mechanisms that can

help with the situation. Using National Electrical Manufacturers Association (NEMA)

enclosures with enclosed locks can help prevent tampering or theft. You can use these

enclosures in locations where access points cannot be hidden easily or in a truly high-risk area.


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Education (Cont.)

New technologies

requiring schools to planfor new surveys

New applications(IP telephony andsurveillance) requiringincreased access pointdensity

Wireless technology provides more than just data access for laptops; it can also be used for IP

telephony or surveillance cameras. These new technologies use additional bandwidth that

requires increased density of access points or use of newer technologies (802.11g and 802.11a).

New site surveys may need to be conducted on locations that have already deployed wireless

technology that was designed exclusively for limited data access.


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OfficesThe wireless office and small office, home office (SOHO) markets are some of the most

quickly emerging markets. This topic discusses the special concerns that the site engineer must

address when surveying the wireless office.


Small Office

Quickly emergingmarket

New solutions beingdeveloped

Many vendors are racing to put out RF products for the home. In the meantime, many

customers are trying to find creative ways to use industrial products in the SOHO environment.

Most small offices will not require a site survey. If the office has fewer than four computers,

then a more economical solution might be an ad hoc network. However, using an access point

ensures a central point for connectivity and troubleshooting.

Some customers may want a site survey anyway, looking ahead to future growth and

expansion. In such instances, a single access point that may be moved or connected via a

wireless repeater can be set up.

Small offices are often located near retail properties that have other small offices. Those offices

may also be using WLAN solutions, so there is the potential of overlapping cells between

different businesses. Channels should be selected with either low use or with a signal strength

that is adequate but that does not send the signal far outside the required coverage area. Part of

securing a network is making it less visible. Lowering the transmit (Tx) power to just what is

needed to provide coverage inside the office area makes the network more secure from outside

the office.

A remote wireless office can also be monitored and surveyed from a centralized management

system like the CiscoWorks 1105 Wireless LAN Solution Engine (WLSE).


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Enterprise Office

95 Feet

120

Feet

Reception

ConferenceRoom

ConferenceRoom

ConferenceRoom

54 Cubes4 Conference Rooms 54 Cubes4 Conference Rooms

95 Feet

ConferenceRoom

120

Feet

Reception

ConferenceRoom

ConferenceRoom

ConferenceRoom

ConferenceRoom

2.4 GHz

4 Access Points

5 GHz

16 Access Points

The wireless office presents a tremendous opportunity today. On the average, enterprise offices

change configurations at least twice a year. This change may involve new additions or

expansions, or it may involve relocating individuals or entire departments. In either case, a

WLAN makes these types of moves much easier. Whether the employee is using a desktop or a

laptop, all that needs to be done is to move the PC and ensure that it is within a WLAN

coverage area.

This ease of use means countless hours saved by the IT department, and money saved on

cabling or recabling expenses.

WLAN equipment with data rates of up to 54 Mbps are likely to be popular in an enterprise

solution, allowing more users and better throughput on a per-access-point basis. The 54-Mbpscoverage area will be approximately one-quarter of the 11-Mbps cell size, meaning more access

points to cover the same area. Also, 5-GHz equipment will not able to penetrate through walls

as well as 2.4-GHz equipment will.

Tools like Cisco Works WLSE can be extremely helpful for setting up access points in a new

office or changing the configuration of access points in an office where a WLAN already exists

but needs to be upgraded. If there are a variety of client types and applications, it is a good idea

to use a walkabout survey with each client. The walkabout with various clients ensures that all

clients will receive adequate coverage.

The number of access points that are required to provide coverage will vary based on the radio

band used, the Tx and receive (Rx) characteristics of the clients, the Tx and Rx configurations

of the access points, and the types of cable and antennas that are used with the access points.


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TransportationTransportation surveys for sites such as rail yards and airports present a variety of situations

and obstacles that site survey engineers must take into consideration. This topic discusses those

situations.


Transportation

Rail Yards

Rail cars

Made of woodand metal

Transport a varietyof cargo

Large

Narrow pathwaysbetween tracks

Rail yards can be difficult to survey and install for many reasons. The cars themselves are very

large and constructed of wood or metal. Cars may be filled with a variety of materials that can

limit the signal, such as livestock, wood, metals, or perishable materials in wooden or

cardboard boxes.

Inside the yard, tall rail cars that are located on parallel tracks form narrow pathways for the

signal. Yagi antennas mounted on poles above the cars at either end of the yard are often the

best solution to this situation, allowing the RF signal to shoot down the narrow pathways.


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Transportation (Cont.)

Airports

Easy two-dimensionalcoverage

Typically open area

Long open pathways

Post-9/11 issues

Rules and regulations

Baggage ramp area

Airports are usually very wide, open areas, with long, open pathways. This type of coverage

makes the survey simpler for the engineer because the survey becomes two-dimensional.

Because of security restrictions after the 9/11 terrorist incident, the engineer should check with

local airport authorities about obtaining the proper clearance. This clearance may require an

FBI background check.

One difficulty in covering airports is when coverage is needed outside the facility, for example,

in the outdoor baggage areas. Much like warehouse installations, these access points may be

subject to extreme weather conditions and may require weatherproof enclosures.

Another situation that the site survey engineer can encounter is that there may already be

wireless gear installed throughout the airport, making channel selection difficult. WLANproducts are used in many airports today by the airlines, as well as by service providers that are

enabling business travelers to connect to the Internet wirelessly while waiting for flights. The

projected wireless application must be in accordance with FAA regulations as well as any other

governing guidelines for the specific airport.


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Transportation (Cont.)

High traffic areas Equipment can be

damaged or stolen ifnot put away properly

Another difficulty in surveying airports is the high traffic there. While people are certainly used

to seeing work crews roaming throughout an airport, it does not mean that they will be cautious

around an engineer during a site survey. Proper care of the site survey materials is important to

prevent theft or injury. A misplaced cable that a traveler trips over could result in a lawsuit.

In addition, today more than ever, airports are concerned with security. Access points and

battery packs, with their flashing lights and wires wrapped around them, can easily be mistaken

for some sort of destructive device. It is important that the site survey engineer meet with all

necessary security personnel before starting the survey.


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GovernmentGovernment facilities, like airports, are at a heightened level of security, and care should be

taken that the site survey equipment is not mistaken for something other than site survey

equipment. There are facilities of every type at government locations, particularly military

facilities. Many military bases may have one of every facility already discussed in this module.

This topic discusses government site survey issues.


Government

Secure facilities

Variety of facilities

Security clearance

Equipment checklists

Security clearances or escorts will likely be required as part of a government site survey. The

vehicle of the site survey engineer may be subject to a search upon entering or leaving the

facility. An equipment list may be required, and the equipment may be checked on a dailybasis.

Equipment lists and proper documentation will be required when entering foreign countries to

perform site surveys. Each country may have different standards and require different

documentation for entering the country with site survey equipment. The site survey engineer

must be prepared and have the proper paperwork to save time, trouble, and potentially the

expense of having the equipment bonded or retained by the customs department.


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Key Requirements for Metropolitan MobileNetworks

Need real-time access to

intelligence information foreffective resourcemanagement

Need for voice, video, anddata communications tosupport mission-criticalsituations within thecommunity

Need to enable mobilenetworks to download andupload data

The government implementation addresses the need for real-time access to people and

resources in the field.

Cisco Metropolitan Mobile Networks are driven by the need for voice, video, and data

communications, as well as the need to enable mobile networks to download and upload data.


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Mobile DevicesImprove Communication Processes

Extend the reach of the network to anylocation in a secure and manageable manner

Provide the tools that are needed to workremotely

Send field information in real time

Public Sector Agency Gains

Provide access to agency

services from the field

Increase employee productivity

and response time while atremote locations

Applications are the driving force for mobile networks to be used. Public agencies need to

share infrastructure and save money.


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Community Residential Deployment

802.11a / 54 Mbps

802.11b / 11 Mbps

802.11b / 11 Mbps

Service Provider

Service Provider / Tower : Cisco Aironet 1400 Series Bridge

Tower / Residential Houses: Cisco Aironet 350 Series Bridge

There are many examples of how a service provider can supply a neighborhood with wireless

coverage using a combination of multiple technologies.


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Local Government Deployment

Police StationCity Hall

Fire Station

Hospital

City Agency Vehicle

On Buildings: Cisco Aironet 350 and 1400 Series Bridges

On Vehicles: BR350, 3220 Mobile Access Router

This is an example of how a mobile network can use many wireless products.


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Review QuestionsUse the practice items here to review what you have learned in this lesson.


Review Questions

What are some of the items that retail storesstock that may interfere with WLAN equipment?

What are some of the equipment concerns thatare involved with surveying hospitals?

How can a WLAN improve productivity in anoffice?

What type of inventory absorbs an RF signal?

IEEE 802.11a and 802.11b and g use what type of

radio frequencies?


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Module 2

Manual Site Survey Tools

OverviewThis module explores the types of equipment that a site survey engineer should always have as

part of a site survey kit.

Module Objectives

Upon completing this module, you will be able to complete the objectives shown in the figure.


Module Objectives

Identify the equipment that is needed to build asite survey kit

Determine the importance of items that areincluded in the site survey kit


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Module Outline

The outline lists the components of this module.


Module Outline

Overview

Access Point Selection

Site Survey Equipment

Summary

Review Questions


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Copyright 2004, Cisco Systems, Inc. Manual Site Survey Tools 2-3

Access Point SelectionDifferent types of sites require different access points. This topic discusses access point

selection.


Access Point Selection

2.4-GHz access points

Supporting remote antennas

Reverse Polarity Threaded NavalConnector (RP-TNC)

1200 Series Access Point (2.4 GHz)

Supporting only internal antennas

1100 Series Access Point

5-GHz access points

1200 Series with 5-GHz module

Attached antenna only

The site survey engineer should always carry more than one device of each model that is

needed in the survey. Many engineers have had a mishap with their only device, resulting in

downtime during the survey. An extra access point or client device allows the survey to

continue without having to wait for a spare to be shipped.

Access points that have radio frequency (RF) connectors allow the site survey engineer the

option of using a variety of antennas to overcome coverage problems or mounting issues. The2.4-GHz antenna ports of the Cisco Aironet 1200 Series Access Point have reverse-polarity

threaded naval connectors (RP-TNCs).

The Cisco Aironet 1100 Series Access Point does not have an RP-TNC, which limits the site

survey engineer to a diversity 2.2 decibels over isotropic (dBi) internal antenna. The 1200

Series Access Point has a 5-GHz module that serves as the 5-GHz CardBus radio and the

antenna. Because of Federal Communications Commission (FCC) requirements, the 5-GHz

antenna module offers two options, a 6-dBi patch mode and a 5-dBi omnidirectional mode. At

some point in the future there may be available a version of a 5-GHz RF module for the 1200

Series Access Point that does not support the Unlicensed National Information Infrastructure

(UNII) 1 band, and therefore may be supplied with remote antenna capability.


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Survey with Correct Equipment

If the customer is purchasing a 1200 Series AccessPoint, then survey with a 1200 Series Access Point.

Analyze the client devices that are intended to be usedin the site.

Many clients support lower transmit power levels than the Ciscocards.

Choose a power setting on the client side that simulates thelowest-powered device that will be used.

Use the same technology that the customer hasspecified for an application (802.11a, 802.11b, 802.11g).

It may be beneficial to use an 802.11g access point for all 2.4-GHzsurveys. The device will support both 802.11b and 802.11g.

Before you begin surveying, it is important to understand what the customer applications will

require for bandwidth and range. This information may make a difference in what technology

will work best for the site. Use the access point the supports the required technology. For

802.11b, the site engineer can use an 802.11g access point and set the data rates to the 802.11b

rates only. This setup allows there to be one less device to maintain and carry.

For the client side, be certain that the power level is set appropriately. Many devices do not

support the 100 milliwatts (mW) that Cisco products support for 802.11b. The engineer should

review the listed client devices from the presite survey report, research to determine the power

levels of these devices, and then select a level that simulates the devices with the lower power

levels.


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Site Survey EquipmentThere are several pieces of equipment that the engineer should bring on any site survey. This

topic discusses the site survey equipment.


Client Cards

Client devices

PC cards

Embeddedlaptop radios

LM cards

MMCX cableconnectors

A survey kit should contain at least one of each type of client device. This kit should include a

laptop with an embedded radio, although the performance may be different than with a

CardBus card due to antenna variations. The device that represents the worst case

performance should be selected. In most cases this device will be either the laptop with an

embedded radio or a device with a CardBus card. Unlike the CardBus or internal radio, the

Peripheral Component Interconnect (PCI) client device and the workgroup bridge offer anantenna that can be placed in an optimum location for the device. The engineer should survey

with the device that the client intends to use. If the client is planning on mounting a terminal

inside of a crane and attaching it via a LAN Module (LM) card with a 5.2-dBi antenna, then the

engineer should survey with the same.

It may also be beneficial to include the adapter for the LAN Module Controller (LMC) card

(MMCXRP-TNC) and an LMC card in the survey kit. The engineer will be able to attach a

variety of antennas to the LMC card and emulate the installation that is desired by the client.


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Antennas

Two of every

antenna that youmay have to use

Diversity

Availability ofantennas

There is no single antenna that is perfect for all applications, and, therefore, a variety of

antennas are offered. The customer, in many cases, dictates antenna choice and placement. A

customer may not want the antenna to be visible, or may wish it be located in a high-traffic

area. By carrying a variety of antennas, the site survey engineer is prepared for any situation.

The minimum collection of antennas should include (but is not limited to) the following:

2.2-dBi rubber dipole antenna (AIR-ANT4941)

2.2-dBi diversity omnidirectional ceiling-mounted antenna (AIR-ANT3351)

5.2-dBi mast-mounted antenna (AIR-ANT2506)

5.2-dBi omnidirectional ceiling-mounted antenna (AIR-ANT1728)5.2-dBi diversity omnidirectional pillar-mounted antenna (AIR-ANT3213)

6.0-dBi diversity patch wall-mounted antenna (AIR-ANT2012)

8.5-dBi hemispherical patch antenna (AIR-ANT3549)

10.0-dBi Yagi mast-mounted antenna (AIR-ANT2410Y-R)

13.5-dBi Yagi mast-mounted antenna (AIR-ANT1949)

An engineer who knows that a special antenna will be required for a particular site survey

should be certain to include that antenna in the kit for that specific site. Site survey engineers

should always survey with the antenna that the client intends to use. If using diversity antennas,

the engineer will need to carry two of every antenna unless the antenna is especially made to

support diversity and contains two antennas. For more antenna options, refer to the CiscoAironet Antenna Reference Guide, which you can find at this URL:

http://www.cisco.com/en/US/products/hw/wireless/ps469/products_data_sheet09186a0080088

83b.html.

Note Do not use a different antenna and attempt to estimate the coverage. The site survey is

being performed to take the guesswork out of the installation.
http://www.cisco.com/en/US/products/hw/wireless/ps469/products_data_sheet09186a0080088http://www.cisco.com/en/US/products/hw/wireless/ps469/products_data_sheet09186a0080088


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Antenna Cable Loss

Try to use the cable that issupplied with the antenna,avoiding long cable runs

when possible.Cisco offers these cables:

LMR400-style cables

20 and 50 feet

Total loss of 1.3 and 3.4dB, respectively

LMR600-style cables

100 and 150 feet

Total loss of 4.4 and 6.6dB, respectively

7.254.4LMR600

10.86.6LMR400

5.8 GHzLoss

(db/100 feet)

2.4 GHzLoss

(db/100 feet)Cable Type

LMR400

LMR600

RF energy is carried between the antennas and the radio equipment through a coaxial cable. An

antenna cable introduces signal loss in the antenna system for both the transmitter and receiver.

Loss of signal strength is directly proportionate to the length of the cable segment. As the

diameter of the cable increases, signal loss is decreased, but at a much higher purchase cost. As

signal frequency increases (higher-numbered channel), signal loss increases.

To reduce signal loss, minimize the cable length and use only low-loss or ultralow-loss antenna

cable to connect radio devices to antennas.


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Mounting Tools

Mounting bracket

Mounting solutions Bright color tape

Velcro

Beam clamps

Zip ties

Secure the accesspoint!

The site survey engineer should always carry an access point mounting bracket (when

available). The kit should also contain various mounting solutions for the bracket (beam

clamps, C-clamps), as well as mounting brackets for each antenna (when available). Zip ties,

duct tape, bailing wire, electrical tape, two-sided tape, Velcro, and paper clips are common

components in the kit of a good engineer.

During a survey there is no bad mounting solution except the solution that does not properly

secure the access point, battery pack, and antenna. A bad mount not only might damage the

equipment but risks injuring the engineer or others when the equipment comes crashing down.


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Battery Pack and Cables

Battery Pack

Charger

Cables

Serial or RJ-45 to DB-9 rollover cable

RP-TNC assembly

Access points require power to operate. There will not always be power available nearby when

you are performing a site survey. A good battery pack will last for at least 8 hours, allowing the

engineer to survey all day without having to recharge.

Also recommended is a fast charger for the site survey tool. If a laptop is used, spare battery

packs that can be charged separately from the laptop are always recommended. Wireless PC

cards require a constant source of power while you are surveying and may reduce battery life to

less than two hours.


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Access Point Markers

Mark access pointand antenna

locations

Bright colors

Durable but easilyremoved

Once the access point placement is determined, it will be necessary to mark the location.

Location markers should be very bright and resistant to dust, grease, and water. Surveyor tape

works very well and comes in a variety of bright colors. Brightly colored signs allow the

engineer not only to mark the location of an access point but to give some detail as to how the

access point is to be configured and mounted, and provide a point of reference to anyone

reading the site survey report. Markers should be sturdy but temporary.


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Measuring Devices

Measuring wheel(horizontal distances)

Height measurement

Rope marked in 10-foot or3-meter increments(vertical distances)

In order to provide the customer with the details that are needed to bid for the installation, the

engineer will have to provide many measurements in the site survey report. And these

measurements need to be as accurate as possible.

If the engineer guesses

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