Presentation on theme: "ESTeem RF Design Tools SECTION 4 - RF System Design."— Presentation transcript:
1 ESTeem RF Design ToolsSECTION 4 - RF System Design
2 Presentation Overview Review Radio BasicsTerminologyUse Information from Radio Basics and Antenna SectionsUse RF Design ProgramInitial Site WorkUsing RF Design ProgramSite Example
3 Presentation Overview Each Radio Application is UniqueWireless is being applied in many applications but few have a working knowledge of designing a successful wireless systemSelecting A Wireless VendorDizzying array ranges from vendorsProvide tools to personally review specifications
4 Steps to Successful Radio Network RF System DesignReview MapsRF Design Program AnalysisOn-Site Radio Site SurveyPhysical Inspection and TestingConfirming Results from RF System DesignSite CommissioningSame Testing on Installed System
5 Presentation Overview RF Design ProgramConservative model of expected radio results\Installed hardware generally higher signal strengthsAllows for modification to system design prior to installation if problems are foundChange Antenna TypeChange Coax Cable TypesProvides means of determining expected data errors
6 Minimum Antenna Height Required to Clear the Radio Horizon Distance (miles)Minimum Height (ft.)Radio HorizonMinimum Height (ft.)EarthAntenna AAntenna BOmni-directional AntennaDirectional AntennaBottom Reference Line for Height Clearance
7 Fresnel ZoneFresnel Zone shows the ellipsoid spread of the radio wavesArea must be clear of obstructions or signal strength will be reducedBlockage in 60% will induce significant signal lossesUse for frequencies above 900 MHz
8 RF Basics - Effective Radiated Power SECTION 4 - RF System DesignEffective Radiated Power (ERP) = Tx Power - Feedline Losses + Antenna GainReceived Signal = Rx Power - Feedline losses + Antenna GainAntenna gain is a logarithmic equation, gain doubles for every 3db increase, but is cut in half for every 3db decrease.High Gain antennas become more directional. This slide give an example of a High Gain UHF antenna.Erp is the rf power plus or minus the gain or loss of the antenna. The loss that is incurred at the transmit site can quite possibly be made up at the receive site, through the same practice.
9 RF Basics - Fade MarginReceiver 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 byTransmitter PowerTransmitter feedline attenuationTransmitting antenna gainReceiving antenna gainReceiver feedline attenuationReceiver SensitivityMaximum Received Signal StrengthFade Margin = Usable Range of ReceiverMinimum Receiver Sensitivity
10 RF Basics - Fade Margin How much Fade Margin? Imperfect world and things are constantly changing.Equipment agesAntennas go out of alignmentUnexpected man-made noise/interferenceBasic rules of thumb for digital transceivers.10 dB - 10% link retries20 dB - 1% link retries30 dB - .1% link retriesLink Listed Marginal <10dBOver 10dB Fade Margin = Green1-10db Fade Margin = Yellow (Marginal)Less than 1dB = Red (Site Not Operational)
11 Initial Site Work 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®
12 Initial Site WorkMost Radio Systems are designed as a “Multiple” of Point to Point RF PathsBase to RemoteBase to RepeaterRepeater to RemoteRepeater to RepeaterEach Path Needs Evaluation
13 Initial Site WorkSketch a site diagram and distances between site nodes. Note LOS blockages.NPump Site #2Control RoomPump Site #1Water TankPump Site #3LOS4 miles5.5 miles5 miles3 miles
14 Initial Site Work Find the elevation of each node above sea level. Reference maps or use a hand held 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.
15 Initial Site Work Antenna Feedline Length Height of Antenna Above Ground for LOS PathEquipment CabinetTerrain Height Above Sea Level
16 Initial Site WorkCalculate Elevation Differential between the lowest node and the remaining nodes.Calculated the Adjusted Antenna Height.Site Elevation Differential + Antenna Height above ground.
17 Initial Site WorkCalculate Elevation Differential between lowest node and remaining nodes.Adjusted Antenna Height = Elevation Differential + Antenna Height above ground.
18 Site Layout Map and Information Pump Site #3N5.5 milesLOSLOSWater Tank3 milesPump Site #2Pump Site #14 miles5 milesControl Room
19 RF Site Design ProgramUse the RF Site Design Program on each point-to-point RF path.In this example we will use the ESTeem 195Eg2.4 GHz FrequencyUse your Site Information Table dataUse Vendor information on transceiver selectedThe RF Site Design Program will provide ESTeem hardware recommended for operating frequency selectedEnter data in the Data Entry Key Board
20 Standard Enclosure Mounting Omni-Directional AntennaDirectional AntennasESTeem Model 195EgCoax CableLightning ArrestorAntenna PortEquipment PortPower Supply
21 Model 195E Outdoor Pole Mount Model 195E Outdoor Fixed Base Hardware DiagramDirectional AntennasOmni-Directional AntennaExternal AntennasDirect Mount AntennasAntenna FeedlineUnit Shown With Rubber Duct AntennasWeather Proof BootWeather Proof BootDirect Pole MountPole Mounting Kit EST P/N AA195PMModel 195EgWeather Proof Front CoverWeather Proof BootPower Over Ethernet CableEthernet Surge Protection EST P/N AA166Ethernet CAT-5e Cable 300 ft. maximumPoE Power Supply EST P/N AA175Ethernet CAT 5e Cable EST P/N: AA09.2To LAN Interface
22 Outdoor Mounting Benefits Remove Long Coax Cable RequiredLower cost ($65-$500 Savings)Lower signal lossNo Lightning Arrestor NeededLower cost ($120 Savings)Also removes loss in jumper cableNo Enclosure NeededGreatly reduced design and installation costs ($300 Savings)
23 RF Path Analysis Control Room to Pump Site #1 Perform a RF Path Analysis from the Control Room to Pump Site #1.Pump Site #3N5.5 milesLOSLOSWater Tank3 milesPump Site #2Pump Site #14 miles5 milesControl Room
24 RF Path Analysis Control Room to Pump Site #1 Path Distance: 4 miles
25 RF Path Analysis Control Room to Pump Site #1 • 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?
26 RF Output Power Levels Peak Power vs Average Power Modulation Based upon type of modulation typeMaximum for peak power set by FCC/DOCModulationAverage power and peak same in Direct SequenceMaximum peaks in OFDM has lower average powerAverage power used in RF Design ProgramModulation type based upon data rateVerify all RF data rates and power levels
27 RF Data Rate Analysis #1Only available for wireless Ethernet products 195Eg, 195Ep and 195EdEnter site information same as RF Path AnalysisFade margin results for each data rateOver 10dB Fade Margin = Green1-10db Fade Margin = Yellow (Marginal)Less than 1dB Fade Margin = Red (Site Not Operational)
28 RF Data Rate Analysis #1Maximum design data rate for application would be 9 MbpsMaximum possible data rate is 18 MbpsActual Data Rates Could Be Higher in Normal Operation195E will not reserve 10dB in operation195E will maintain highest data rate possible
29 RF Data Rate Analysis #2Same application using higher gain directional antennaAA204Eg 19dB Parabolic directional antennaLegal for use from single remote to omni-directional
30 RF Data Rate Analysis #2Much higher RF Data Rates available with higher fade marginMaximum design data rate for application would be 24 MbpsMaximum possible data rate is 48 Mbps
31 RF Path Analysis Control Room to Pump Site #2 Perform a RF Path Analysis from the Control Room to Pump Site #2.Pump Site #3N5.5 milesLOSLOSWater Tank3 milesPump Site #2Pump Site #15 miles4 miles24 MbpsControl Room
32 RF Path Analysis Control Room to Pump Site #2 Path Distance: 5 miles
33 RF Path Analysis Control Room to Pump Site #2 Maximum design data rate for application would be 24 MbpsMaximum possible data rate is 36 Mbps
34 RF Path Analysis Control Room to Water Tank Perform a RF Path Analysis from the Control Room to Water Tank.Pump Site #3N5.5 milesLOSLOSWater Tank3 milesPump Site #2Pump Site #14 miles5 miles24 Mbps24 MbpsControl Room
35 RF Path Analysis Control Room to Water Tank Path Distance: 3 miles
36 RF Path Analysis Control Room to Water Tank Maximum design data rate for application would be 9 MbpsMaximum possible data rate is 24 Mbps
37 Water Tank to Pump Site #3 Perform a RF Path Analysis from the Water Tank to Pump Site #3.Pump Site #3N5.5 milesLOSLOSWater Tank9 MbpsPump Site #23 milesPump Site #14 miles5 miles24 Mbps24 MbpsControl Room
38 RF Path Analysis Water Tank to Pump Site #3 Path Distance: 5.5 miles
39 RF Path Analysis Water Tank to Pump Site #3 Maximum design data rate for application would be 24 MbpsMaximum possible data rate is 36 Mbps
40 Pole Mounting Water Tank to Pump Site #3 Problem areasFresnel Zone WarningIncrease height of the Pump Site #3 AntennaNeed 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.
41 Model 195Eg Maximum Range Two Directional Antennas Cable Loss Range AA204Eg is the highest gain antenna that the unit is type accepted for.19 dB gainCable Loss.6 dB because the unit is pole mounted.RangedB Fade MargindB Fade Margin
42 Model 195Eg Maximum Range Range 179 miles @ 1 Mbps @ 6 dB Fade Margin Antenna Height = 4,010 ft at each endFresnel Zone (60%) = 185 feetThis would probably be usable only from mountain top to mountain topdB Fade MarginAntenna Height = 54 ft. at each endThis is a practical height
43 Model 195Eg Maximum Range Two Omni-Directional Antennas Cable Loss AA20Eg6 dB gainCable Loss.6 dB because the unit is pole mountedRange 6 dB with Fade Margin1 Mbps = minimum antenna height of 45 ft Mbps = minimum antenna height of 36 ft Mbps = minimum antenna height of 31 ft Mbps = minimum antenna height of 26 ft Mbps = miles @ minimum antenna height of 14 ft.
44 Conclusions Education is Best Means to Confidence Use the Tools Reliability is only as good as the system designUse the ToolsCompare different vendor’s hardwareReview specifications and claimsRadio Applications Are Not DifficultPlaning and evaluation are best keys to success