Site Survey UCSC -Engineering 2

Linda Rosewood – Lynne Sheehan – Bob Vitale

Equipment: WinXP Laptop with NetstumblerMacOSX Laptop with KisMACCisco 1200 AP with two types of antennas

1. Compare 802.11b/g coverage using 2.2dBi “duck” and 5.2dBi ceiling mount antennas.

2. Investigate interesting propagation effects-through walls, windows, between floors, down corridors.

3. Map a coverage area for the 2nd floor using APs positioned in the corridor and positioned in a lab. Do the results help determine AP placement for building?

Objective: Learn About & Understand Propagation in the Engineering 2 Building

South Corridor Note “decorative” metal ceiling tiles

2nd Floor Survey Areas

Faculty offices

Labs

Academic Support

Conferenceroom

Conference room

Loc #2: Rear Corridor Ceiling, AP above 5.5dBi antennas hang below

Loc #1: Inside Lab, survey done with 2.2dBi “ducks” and 5.5dBi ceiling mount omnis

Ducks vs. Ceiling Mount Omni

5.5dBi Suspended Ceiling Mount Omni- Directional AntennasCisco AIR-ANT1728Cost: $105 each

2.2dBi Rubber Duck AntennasCisco AIR-ANT4941Cost: $15 each

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1615

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108

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E2 2nd Floor West Survey – Rubber Duck vs. Ceiling Mt Omni

See Next Slide for values, most points Omnis beat ducks by 1 to 6 dB, average 3dB improvement

Hidden Area behind elevators

Hidden Area behind ducts/walls

   RubberDuck 

Ceiling Mount Omni  Diff

Location# Name Average STDEV Average STDEV + = om

1Room 208

3 feet from AP 63 7 61 10 -2

2Outside Rm 208

Main Cooridor 49 7 54 5 5

3Bench 1

Outside Rm 210 49 6 54 5 5

4Bench 2

Outside Rm 215 33 5 37 9 3

5Room 216

cube close to AP 32 3 35 4 2

6Room 216

cube furtherest away 31 4 33 4 2

7Room 215

card towards AP 22 4 23 5 2

8Room 215

card away from AP 19 2 19 3 1

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Room206Card pointed SouthA/C Unit between AP/Card 49 4 54 3 4

10Room 205

cube closest to windows 39 4 45 2 6

11Hall behind

Room 208 53 10 59 7 6

12Room 237B

Office w/Door closed 45 3 49 3 4

13 Interactive Space 48 3 49 8 1

14Benches outside

E2-219 21 4 25 6 4

15Room 201

Last Cubicle on Windows 37 3 42 5 5

16Cowboy Chairs

2nd Chair in 20 6 18 3 -2

17Room 308

Immediately above AP 16 2 16 3 0

E2 2nd Floor – East Survey

Hidden Areas due to coated glass, walls and ductwork

802.11b PropagationFreeSpace vs. Through Coated Glass

Compare Propagation: Glass vs. Free Space

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1 13 25 37 49 61 73 85 97 109 121 133 145 157 169 181 193 205 217 229 241 253 265 277 289 301 313 325 337 349 361 373 385 397 409 421 433 445 457

Data Points

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Free Space (10ft) IndoorGlass Window (10ft)Free Space (10ft) Outside

Average Loss due to GlassUsing Indoor Free Space Measurement: 19dB

Using Outdoor Free Space Measurement: 24dB

Compare Propagation: Metal Stud Wall vs. Free Space

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1 7 13 19 25 31 37 43 49 55 61 67 73 79 85 91 97 103 109 115 121 127 133 139 145 151 157 163 169 175 181 187 193 199 205 211

Data Points

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Indoor Free Space (5ft total dist)

With Wall Insert (5ft total dist)

Average Loss due to Metal Stud WallUsing Indoor Free Space Measurement: 3dB

Glass Corridor vs. Free SpaceIs there a difference at 173 feet?

Glass Corridor vs Free Space Outdoor PropagationDistance on both is 173 feet

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1 29 57 85 113 141 169 197 225 253 281 309 337 365 393 421 449 477 505 533 561 589

Data Point

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Free Space - Outdoor (173ft)

Glass Corridor

Data FreeSpace Glass CorridorAverage 35 39Std Dev 5 15Max 44 51Min 11 0

Proposed 2nd Floor Coverage Plan

Faculty offices

Labs

Academic Support

Conferenceroom

Conference room

Channel 1

Channel 11

Channel 6

Channel 1