Review Maps RF Design Program Analysis RF System Design Physical Inspection and Testing Confirming...

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ESTeem RF System Design

• Review Maps• RF Design Program Analysis

RF System Design

• Physical Inspection and Testing• Confirming Results from RF System Design

On-Site Radio Site Survey

• Same Testing on Installed System

Site Commissioning

Steps to Successful Radio Network

• Wireless is being applied in many applications but few have a working knowledge of designing a successful wireless system

Each Radio Application is Unique

• Dizzying array ranges from vendors• Provide tools to personally review

specifications

Selecting A Wireless Vendor

RF Design Overview

RF Design Program

• Conservative model of expected radio results• Installed hardware generally higher signal strengths

• Allows for modification to system design prior to installation if problems are found• Change Antenna Type• Change Coax Cable Types

• Provides means of determining expected data errors

Presentation Overview

Antenna A Antenna B

Minimum Height (ft.)

Distance (miles)

Radio Horizon

Directional Antenna

Omni-directional Antenna

Bottom Reference Line for Height Clearance

Minimum Antenna Height Required to Clear the Radio Horizon

Fresnel Zone shows the ellipsoid spread of the radio waves

Area must be clear of obstructions or signal strength will be reduced

Blockage in 60% will induce significant signal losses

Use for frequencies above 900 MHz

Fresnel Zone

Effective Radiated Power (ERP) = Tx Power - Feedline Losses + Antenna Gain

Received Signal = Rx Power - Feedline losses + Antenna Gain

RF Basics - Effective Radiated Power

RF Basics - Fade Margin

Receiver Sensitivity is the minimum signal level in dB needed by the receiver to output received data.

Fade Margin in dB is the amount of received signal above the receiver’s minimum required useable Receiver Sensitivity.

Fade Margin is controlled by• Transmitter Power • Transmitter feedline attenuation• Transmitting antenna gain• Receiving antenna gain• Receiver feedline attenuation• Receiver Sensitivity

Minimum Receiver Sensitivity

Maximum Received Signal Strength

Fade Margin = Usable Range of Receiver

How much Fade Margin?

• Imperfect world and things are constantly changing.• Equipment ages• Antennas go out of alignment• Unexpected man-made noise/interference

• Basic rules of thumb for digital transceivers.• 10 dB - 10% link retries• 20 dB - 1% link retries• 30 dB - .1% link retries

• Link Listed Marginal <10dB• Over 10dB Fade Margin = Green• 1-10db Fade Margin = Yellow (Marginal)• Less than 1dB = Red (Site Not Operational)

RF Basics - Fade Margin

Draw a simple layout of the proposed system.

Determine Line-of-Sight (LOS) distances between each point to point radio path by:

• Site maps.• If Latitude and longitude are known use the “Distance

Between Two Points Calculator” in the RF Design Program.• Use a hand held GPS.• Google Earth®

Initial Site Work

Most Radio Systems are designed as a “Multiple” of Point to Point RF Paths

• Base to Remote• Base to Repeater• Repeater to Remote • Repeater to Repeater

Each Path Needs Evaluation

Initial Site Work

Sketch a site diagram and distances between site nodes. Note LOS blockages.

Initial Site Work

Pump Site #2

Control Room

Pump Site #1

Water Tank

Pump Site #3

LOSLOS

4 miles

5.5 mile

5 miles

3 miles

LOSLOS

Find the elevation of each node above sea level.

• Reference maps• Handheld GPS.• Google Earth®

Estimate installed antenna height at each node above ground level to achieve LOS to destination site.

Estimate feedline length from antenna to equipment cabinet.

Initial Site Work

Accurate site locations

Longitude and Latitude

Distance between locations

Side profile for Line of Sight (LOS) measurement

Google Earth

Antenna

Feedline Length

Equipment Cabinet

Terrain Height Above Sea Level

Height of Antenna Above Ground for

LOS Path

Initial Site Work

Calculate Elevation Differential between the lowest node and the remaining nodes.

Calculated the Adjusted Antenna Height.

• Site Elevation Differential + Antenna Height above ground.

Initial Site Work

Name Site Elev. Elev. Dif. Ant. Hgt. Adj. Ant. Hgt. Feedline Lgh.Control Room 560 80 20 100 30Pump Site #1 570 90 20 110 30Pump Site #2 820 340 20 360 30Water Tank 1100 620 120 740 130Pump Site #3 480 0 15 15 30

Site Information

Calculate Elevation Differential between lowest node and remaining nodes.

Adjusted Antenna Height = Elevation Differential + Antenna Height above ground.

Initial Site Work

Name Site Elev. Elev. Dif. Ant. Hgt. Adj. Ant. Hgt. Feedline Lgh. Ant. Type

Control Room 560 80 20 100 30 Omni-Dir.

Pump Site #1 570 90 20 110 30 Directional

Water Tank 1100 620 120 740 130 Omni-Dir.

Site Information

Pump Site #2

Control Room

Pump Site #1

Water Tank

Pump Site #3

4 miles

5 miles

3 miles

LOS LOS

Site Layout Map and Information

Use the RF Site Design Program on each point-to-point RF path.

• In this example we will use the ESTeem 195Eg• 2.4 GHz Frequency • Use your Site Information Table data• Use Vendor information on transceiver selected

• The RF Site Design Program will provide ESTeem hardware recommended for operating frequency selected

• Enter data in the Data Entry Key Board

RF Site Design Program

Standard Enclosure Mounting

Lightning Arrestor

Directional Antennas

Omni-Directional Antenna

Coax CableESTeem

Model 195Eg

Power Supply

Model 195E Outdoor Pole Mount

Model 195Eg

Omni-Directional Antenna

Model 195E Outdoor Fixed Base Hardware

Diagram

Direct Pole MountPole Mounting Kit EST P/N AA195PM

Power Over Ethernet Cable

Ethernet CAT-5e Cable 300 ft. maximum

Weather Proof Boot

Weather Proof Front Cover

Antenna Feedline

External Antennas

Directional Antennas

Weather Proof Boot

To LAN Interface

PoE Power Supply EST P/N AA175

Ethernet Surge Protection

EST P/N AA166

Ethernet CAT 5e Cable

EST P/N: AA09.2

Unit Shown With Rubber Duct Antennas

Direct Mount Antennas

Remove Long Coax Cable Required

• Lower cost ($65-$500 Savings) • Lower signal loss• Increased Range and/or data rate

No Lightning Arrestor Needed

• Lower cost ($120 Savings)• Also removes loss in jumper cable

No Enclosure Needed

• Greatly reduced design and installation costs ($300 Savings)

Outdoor Mounting Benefits

Pump Site #2

Control Room

Water Tank

Pump Site #3

4 miles

5 miles

3 miles

LOSLOS

Perform a RF Path Analysis from the Control Room to Pump Site #1.

Name Adj. Ant. Hgt. Feedline Lgh. Ant. Type

Control Room 100 30 Omni-Dir.

Pump Site #1 110 30 Direction

Pump Site #1

RF Path AnalysisControl Room to Pump Site #1

Name Adj. Ant. Hgt. Feedline Lgh. Ant. Type

Control Room 100 30 Omni-Dir.

Pump Site #1 110 30 Direction

Path Distance: 4 miles

• In this example we used the highest Rx Sensitivity of -89 dB for a RF data rate of 1Mbps. This will give a 12.6 dB Fade Margin for a 4 mile path length.• What would be the maximum data rate for this RF link?

RF Path Analysis Control Room to Pump Site #1

Peak Power vs Average Power

• Based upon type of modulation type• Maximum for peak power set by FCC/DOC

Modulation

• Average power and peak same in Direct Sequence • Maximum peaks in OFDM has lower average power

Average power used in RF Design Program

• Modulation type based upon data rate• Verify all RF data rates and power levels

RF Output Power Levels

Only available for wireless Ethernet products 195Eg, 195Ep, 195Ea and 195Ed

Enter site information same as RF Path Analysis

Fade margin results for each data rate

• Over 10dB Fade Margin = Green• 1-10db Fade Margin = Yellow (Marginal)• Less than 1dB Fade Margin = Red (Site Not Operational)

RF Data Rate Analysis #1

Maximum design data rate for application would be 9 Mbps

Maximum possible data rate is 18 Mbps

Actual Data Rates Could Be Higher in Normal Operation• 195E will not reserve 10dB in operation• 195E will maintain highest data rate possible

Same application using higher gain directional antenna

AA204Eg 19dB Parabolic directional antenna

Legal for use from single remote to omni-directional

Much higher RF Data Rates available with higher fade margin

Pump Site #2

Control Room

Pump Site #1

Water Tank

Pump Site #3

Name Adj. Ant. Hgt. Feedline Lgh. Ant. TypeControl Room 100 30 Omni-Dir.Pump Site #2 360 30 Directional

4 miles

5.5 mile

5 miles

LOSLOS

Perform a RF Path Analysis from the Control Room to Pump Site #2.

24 Mbps

3 miles

Name Adj. Ant. Hgt. Feedline Lgh. Ant. TypeControl Room 100 30 Omni-Dir.Pump Site #2 360 30 Directional

• Maximum design data rate for application would be 24 Mbps• Maximum possible data rate is 36 Mbps

Name Adj. Ant. Hgt. Feedline Lgh. Ant. TypeControl Room 100 30 Omni-Dir.Water Tank 740 130 Omni-Dir.

Perform a RF Path Analysis from the Control Room to Water Tank.

24 Mbps

RF Path AnalysisControl Room to Water Tank

Pump Site #2

Control Room

Pump Site #1

Water Tank

Pump Site #3

5.5 mile

5 miles

LOSLOS

3 miles

4 miles

Name Adj. Ant. Hgt. Feedline Lgh. Ant. TypeControl Room 100 30 Omni-Dir.Water Tank 740 130 Omni-Dir.

RF Path AnalysisControl Room to Water Tank

Name Adj. Ant. Hgt. Feedline Lgh. Ant. TypeWater Tank 740 130 Omni-Dir.Pump Site #3 15 30 Directional

Site Information

Perform a RF Path Analysis from the Water Tank to Pump Site #3.

9 Mbps

Water Tank to Pump Site #3

24 Mbps

Pump Site #2

Control Room

Pump Site #1

Water Tank

Pump Site #3

5.5 mile

5 miles

LOSLOS

3 miles

4 miles

Path Distance: 5.5 miles

Name Adj. Ant. Hgt. Feedline Lgh. Ant. TypeWater Tank 740 130 Omni-Dir.Pump Site #3 15 30 Directional

Site Information

RF Path AnalysisWater Tank to Pump Site #3

• Maximum design data rate for application would be 24 Mbps• Maximum possible data rate is 36 Mbps

Pole MountingWater Tank to Pump Site #3

Problem areas◦ Fresnel Zone Warning

Increase height of the Pump Site #3 Antenna Need to increase from 15 ft. to 33 ft. to be above the minimum height

requirements for the Fresnel Zone. In this example I increased height to 40 ft. for a margin of error.

Two Directional Antennas

• AA204Eg is the highest gain antenna that the unit is type accepted for.• 19 dB gain

Cable Loss

• .6 dB because the unit is pole mounted.

• 179 miles @ 1 Mbps @ 10 dB Fade Margin• 8 miles @ 54 Mbps @ 10 dB Fade Margin

Model 195Eg Maximum Range

• 179 miles @ 1 Mbps @ 10 dB Fade Margin• Antenna Height = 4,010 ft at each end• Fresnel Zone (60%) = 185 feet• This would probably be usable only from mountain top to mountain top

• 8 miles @ 54 Mbps @ 10 dB Fade Margin• Antenna Height = 54 ft. at each end• This is a practical height

Two Omni-Directional Antennas

• AA20Eg• 6 dB gain

Cable Loss

• .6 dB because the unit is pole mounted

Range 6 dB with Fade Margin

1 Mbps = 9.0 miles @ minimum antenna height of 45 ft.

5.5 Mbps = 5.7 miles @ minimum antenna height of 36 ft.

Education is Best Means to Confidence

• Reliability is only as good as the system design

Use the Tools

• Compare different vendor’s hardware• Review specifications and claims

Radio Applications Are Not Difficult

• Planning and evaluation are best keys to success

Conclusions

Site Surveys

Develop Testing Plan

• Customer’s RF Communication Desires• Gather Maps, Site Layout, etc.

On-site Radio Measurements

• Confirm RF Design Results• RF Signals & Noise• Determine Radio Paths

Gather Site Information

• Physical Site Inspection• Installation Information

What is an RF Site Survey

Layout The Site• Review Topographic Maps• Site Walk-down

Pre-Test Preparation• Lay out equipment• Reference Site

Site Testing

Test Results

• Site Survey Report

Procedure

Review Map

• Area Topography• Repeaters - Antenna types

Site Walk down

• Look for LOS blockages• Type of antenna mounting structure and height• Routing of feedlines• Environmental considerations

Site Layout

Install Antenna• Antenna placement• SWR measurement

Conduct Spectrum Analysis

Choose Frequency for Testing• Isolated frequency• Check for license availability

Quick Connect Test

Reference Site

Proceed To Most Questionable Remote First

• Furthest or least likely to communicate direct

Install and Test Antenna

Quick connect• Status light• If no connection, determine repeater site

Signal Strength

Data Transmission Testing

• Polling Test or Pings

Remote Sites

Status Menu in Model 195 Series

• Repeater Peer List• RF Data Rates

Spectrum Analyzer

• View Noise and Signal• Other Transmitters in Area

10dB above minimum signal strength for fade margin

Received Signal Strength

Conduct Test to All Communication Paths

• Remote to master• Remote to repeater• Repeater to master

Long Term Testing

• Overnight Polling Test

Data Transmission Testing

Master

Repeater

RemoteRemote

All Signal Strengths Above Fade Margin

• 10dB above Minimum for Spread Spectrum

Antenna Heights and Locations

Operating Frequency

Background Noise

Data Transmission Tests

• From every site• Overnight to farthest site

Testing Results

Test Results

RF System Layout

Accurate Bill of Material

Installation Instructions

Safety Concerns

Modem Program Commands

Reliable Operating Frequency and License Information.

Site Survey Report

Site Commissioning

• Equipment Installed• Same testing as site survey with installed hardware

• Long term Ping Test• Confirmed reliable operation• Equipment Commissioned

Site Commissioning

Review Maps RF Design Program Analysis RF System Design Physical Inspection and Testing Confirming...

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