RF Path Analysis

REV

F 0

FILE NAME

BY DATE

J.R. Lawrence

0

Issued for general use.

HOP NAME

First Issue

HOP TYPE

SITE A to SITE B

August 7, 2000 Your Name Date

GEN

Unlicensed Radio Hop Data Sheet 01 SITE NAME

LOCATION TAG

02 ADDRESS

CITY

BY

TOWER SITE A

ANTENNA / COAX RADIO

APRVD

JRL

ST

ADDRESS (If applicable)

ZIP

DEG

MIN

04 OTHER INFO

32

SEC

29

CITY

52.0

COUNTY NAME

87

NORTH LATITUDE

ST

43

5.0

Zip

WEST LONGITUDE

27

NAD

195

05 ELEVATION

TOWER HEIGHT

HEIGHT AGL

06 MFR

MODEL

FCC TOWER #

ROHN

GAIN

ANT. MFR.

59.4

FT

360

METERS

109.7

FT

555

METERS

169.2

FT

METERS

80

07 OTHER INFO 08 MFR

MODEL

TYPE

SIZE

BEAM W.

ANT. MODEL

229.3 DEG

09 BEARING - A to B

HEIGHT AGL

OTHER

10 COAX MFR

TYPE

SIZE

11 COAX 1 LENGTH

FREQ

ATTENUATION

12 COAX 2 LENGTH

FREQ

ATTENUATION

GRID DISH (or other)

160

48.8

FT

COAX MFR.

180 30

33.0 dBi

SIZE IN FEET

COAX TYPE

54.9 9.1

FT FT

METERS METERS

3.5

DEG

METERS

2455.0 MHz 0.0 MHz

COAX SIZE IN INCHES

2.22 dB per 100 FT 5.93 dB per 100 FT

4.0 dB LOSS 1.8 dB LOSS

13 OTHER INFO 14 MFR

MODEL

15 XMIT FREQ

SERIAL XMIT GAIN

W-M LYNX

CONFIG XCEIVE SENS

31250

2455.00000 MHz

27.0 dBm

-94.0 dBm

16 OTHER INFO

+/- 20 TO +/-63 Volts, < 45 W

17 POWER SUPPLY MISC

CHKD

SITE "A" NAME

POINT CODE

COUNTY

03 LATITUDE / LONGITUDE

REV

REVISION

18 19

GEN

20 21 SITE NAME

LOCATION TAG

POINT CODE

22 ADDRESS

CITY

ST

COUNTY

23 LATITUDE / LONGITUDE

DEG

MIN

TOWER

24 OTHER INFO

SITE B

SEC

32

23

23.0

87

NORTH LATITUDE

52

1.0

WEST LONGITUDE

27

NAD

25 ELEVATION

TOWER HEIGHT

HEIGHT AGL

26 MFR

MODEL

FCC TOWER #

310

94.5

FT

270

METERS

82.3

FT

580

METERS

176.8

FT

METERS

27 OTHER INFO 28 MFR

ANTENNA/COAX

SITE "B" NAME

ZIP

MODEL

TYPE

SIZE

GAIN

33.0 dBi

BEAM W.

29 BEARING - B to A

HEIGHT AGL

OTHER

30 COAX MFR

TYPE

SIZE

31 COAX 1 LENGTH

FREQ

ATTENUATION

32 COAX 2 LENGTH

FREQ

ATTENUATION

49.3 DEG 270 30

250 82.3 9.1

FT FT

76.2

FT

DEG

METERS

METERS

2455.0 MHz

METERS

MHz

2.22 dB per 100 FT 5.93 dB per 100 FT

6.0 dB LOSS 1.8 dB LOSS

RADIO

33 OTHER INFO 34 MFR

MODEL

35 XMIT FREQ

SERIAL XMIT GAIN

CONFIG XCEIVE SENS

W-M LYNX

31250

2455.00000 MHz

27.0 dBm

-94.0 dBm

36 OTHER INFO

MISC

37

SAME AS ABOVE

38 POWER SUPPLY 39

COMMON DATA

40 41 HOP DISTANCE

HOP FACTORS

42 SYSTEM GAINS 43 SYSTEM LOSSES 44 FADE MARGIN

COMMENTS

45 PATH AVAILABILITY

PREDICTED DOWNTIME

11.45 MILES 18.43 KM 0.50 (0.125 DRY to 0.500 HUMID) 1.00 (4.0 SMOOTH to 0.25 MOUNTAINS) 27.0 dB XMIT 94.0 dB XCEIVE 33.0 dB "A" ANT 33.0 dB "B" ANT 187.0 TOT 131.1 dB PATH 5.8 dB COAX "A" 7.8 dB COAX B 7.8 dB OTHER 152.4 TOT 34.6 dB 99.999840% 50 SEC / YR or 0.84 MIN / YR or 0.01 HR / YR

NOTES

1 FADE MARGIN, AVAILABILITY AND DOWNTIME CALCULATIONS ARE FOR SITE "A" TO SITE "B". 2 SPIKE IN GROUND ELEVATION THROUGH FOLIAGE IN GRAPH IS AN EXAMPLE OF AN OBJECT, SUCH AS A TOWER, IN OR NEAR THE LOS PATH.

600 500 400 300 200 100 0

RRR RRRR RRRR RRRR RRRR RRR o o o o o o o o o o o o o o o o o o o o o o www wwww wwww wwww wwww www LOS Foliage

60% Fresnel

Adjusted

© Copyright 2000, El Paso Energy

Elevation (feet)

Path Profile 575.00 550.00 525.00 500.00 475.00 450.00 425.00 400.00 375.00 350.00 325.00 300.00 275.00 250.00 225.00 200.00 175.00 150.00 125.00 100.00 75.00 50.00 25.00 0.00 Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row Row 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 Data Point LOS

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Fresnel

60% Fresnel

08/24/2009

Adjusted

Foliage

Profile

Row Row Row 1 32 33

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Profile

Rev

Date

Description

TOPO DATA CALCULATIONS

Data Point 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

Distance d1 (miles) 0.00 0.55 1.09 1.64 2.18 2.73 3.27 3.82 4.36 4.91 5.45 6.00 6.55 7.09 7.64 8.18 8.73 9.27 9.82 10.36 10.91 11.45

Frequency Path Length Curvature Height k Foliage Height Beam elevation

21362473.xls

Ground Elevation 195 200 190 200 200 212 190 250 250 200 250 292 250 250 200 273 200 230 150 250 200 310

Distance d2 (miles) 11.45 10.91 10.36 9.82 9.27 8.73 8.18 7.64 7.09 6.55 6.00 5.45 4.91 4.36 3.82 3.27 2.73 2.18 1.64 1.09 0.55 0.00

2.46 11.45 h = d1*d2 / 1.5k 1.33 40 0

LOS Path 355.00 364.76 374.52 384.29 394.05 403.81 413.57 423.33 433.10 442.86 452.62 462.38 472.14 481.90 491.67 501.43 511.19 520.95 530.71 540.48 550.24 560.00 GHz miles feet 4/3 (default) feet radians

Path Information Fresnel 60% Fresnel Clearance Clearance 355 355 332 345 329 347 330 352 333 357 337 364 343 371 350 379 357 388 366 397 375 406 385 416 395 426 406 437 418 448 431 459 445 471 460 484 476 498 495 513 517 530 560 560

Adjusted Elevation 195.00 202.97 195.65 208.03 210.11 223.90 203.39 264.58 265.47 216.06 266.36 408.36 266.06 265.47 214.58 286.39 211.90 240.11 158.03 255.65 202.97 310.00

Foliage Elevation 195.00 242.97 235.65 248.03 250.11 263.90 243.39 304.58 305.47 256.06 306.36 348.36 306.06 305.47 254.58 326.39 251.90 280.11 198.03 295.65 242.97 310.00

Earth Curvature 0 2.97 5.65 8.03 10.11 11.90 13.39 14.58 15.47 16.06 16.36 16.36 16.06 15.47 14.58 13.39 11.90 10.11 8.03 5.65 2.97 0

Point Adder Notes

100 Example of a structure in or near the path.

Notes: 1) Columns in feet unless otherwise noted. 2) The user input areas are un-shaded.

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Topo Data

Rev Date

Description

BEARING & DISTANCE CALCULATION Definition of Variables

~ A B La Lb L D C C'

:= := := := := := := := :=

Value 32.49778 32.38972 87.71806 87.86694 -0.14889 below below below

Units deg deg deg deg deg degrees of arc deg deg

Notes Site "A" Latitude in decimal degrees. (Note 1) Site "B" Latitude in decimal degrees. (Note 1) Site "A" Longitude in decimal degrees. (Note 1) Site "B" Longitude in decimal degrees. (Note 1) Longitude of Site "A" minus the Longitude of Site "B" Distance along path. True bearing from North if sin L is positive. True bearing from North if sin L is negative, (360 - C).

Units rad/deg km/deg mi/km deg/rad

Notes Note 2

Definition of Constants -

:= := := := :=

Value 0.017453293 111.2300 0.62137119 57.295779

Note 2 Note 2

Equations 1) 2)

cos D = sin A sin B + cos A cos B cos L cos C = (sin B - sin A cos D) / (cos A sin D)

Solution Param. sin A cos A sin B cos B sin L cos L cos D D sin D cos C C C C' D D D

= = = = = = = = = = = = = = = = =

Value 0.537266910 0.843412276 0.535675343 0.844424021 -0.002598598 0.999996624 0.999995817 0.002892403 0.002892399 -0.651498132 2.280353827 229.345 49.345 0.165722469 18.433 11.454

Units n/a n/a n/a n/a n/a n/a n/a rad n/a n/a rad deg deg deg km mi (statute)

Notes

From Equation 1 above

From Equation 2 above Note 4 Note 4 degrees of earth surface arc. Note 4 Note 4

Notes: 1) 2) 3) 4) 21362473.xls

Value from user input on the Cover Sheet. From "Handbook of Chemistry & Physics", 59th Edition, CRC Press. There is no user input on this sheet. This value is shown on the Cover Sheet. 08/24/2009

B_D Calc

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B_D Calc

Rev Date

Description

PATH LOSS CALCULATION Definition of Variables

~ f D Lfs

:= Value := 2.45500

Units GHz

Notes Operating Freq. Value from user input on the Cover Sheet.

:= 11.45393 := calc below

mi (statute) dB

From B&D Calc Sheet. Free-space path loss.

Units dB

Notes Pseudo constant depends upon frequency.

Definition of Constants K

:= Value := 102.07

Equation 1)

Lfs := K + 20 log f + 20 log D

Note 2

Solution Param. log f log D Lfs

= = = =

Value 0.390051496 1.058954445 131.051

Units n/a n/a dB

Notes

This value is shown on the Cover Sheet.

Notes: 1) 2)

21362473.xls

There is no user input on this sheet. Formula from the Adtran Tracer manual and from the Andrew Catalog. Values for K from Cylink manual.

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Path Loss

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Path Loss

Rev Date

Description

AVAILABILITY CALCULATION Definition of Variables

~ a b f d FM

:= := := := := :=

Value 1.00 0.50 2.45500 11.45393 34.60062

Units n/a n/a GHz mi (statute) dB

Notes Terrain Roughness factor. User input from Cover Sheet. Climate factor. User input from Cover Sheet. Frequency. User input from the Cover Sheet. Distance. Calculated value from the B&D Calc Sheet. Fade Margin. Calculated value from the Cover Sheet.

Units sec/yr

Notes Seconds per mean solar year.

Definition of Constants s

:= Value := 31558149.5

Equation 1)

Availability (Av) = (1 - a * b * 10-5 * f/4 * d 3 * 10-FM/10) * 100% (Note 2)

Solution Param. Av dt1 dt2 dt3

= = = = =

Value 99.999840% 50 0.84 0.014

Units sec/yr min/yr hr/yr

Notes Availability Predicted downtime per year.

Notes: 1) 2)

There is no user input on this sheet. Barnett's Model for outage or "unavailability". References: "Engineering Considerations for Microwave Communications Systems", AG Communication System, 4th Edition, 1991, pp. 68-69.

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Availability

21362473.xls

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Availability

Rev

Date

Description

OTHER GAINS & LOSSES

LOSS Description Connectors Coax Cable Surge Suppressor Jumper Radome Attenuator Filter Cable Degradation Antenna/Feedline estimated mismatch Other, Misc.

Qty 8 2

Each 0.10 1.00

1 2

1.00 2.00

Total Units 0.800 dB 2.000 dB 0.000 dB 0.000 dB 0.000 dB 0.000 dB 1.000 dB 4.000 dB 0.000 dB 0.000 dB 0.000 dB 0.000 dB 0.000 dB

Basis

Example of an estimated, temporary loss. Example of an estimated, temporary loss.

7.800 dB

GAIN Description Amplifier

Qty

Each

Total Units 0.000 dB 0.000 dB 0.000 dB

Basis

0.000 dB NET LOSS =

7.800 dB

Notes: 1)

21362473.xls

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Other G _ L

Rev Date

Description

Spreadsheet Documentation 1.0 Purpose and Scope The purpose of this "Program" is to provide data-sheet style documentation for an unlicensed radio path, (hop), and to provide calculations to support the viability of the hop. Although the calculations used herein are generally applicable to several VHF, UHF, and microwave bands, the intended scope of application is the 902-928 MHz, the 2.4-2.483 GHz, and the 5.7 GHz unlicensed spread spectrum, (ISM), bands. This program is not intended to replace commercial programs - it is intended to provide a more readily available tool for individuals involved in path analysis. It was created for use by Communications Engineers and Technicians and should not be used by those not familiar with path analysis. Note: This spreadsheet is not suitable for microwave system design; a more sophisticated analysis is required. 2.0 General The Program is an Excel Workbook consisting of several spreadsheets including: Cover; Profile; Topo Data; B&D Calc (Bearing & Distance); Path Loss; Availability; and Other G&L (Gains & Losses). Calculations and input/output data span the various spreadsheets. The user should be certain he is using the latest Program version. See the Version information in the Summary paragraph for information. Contact the author for the latest version. 3.0 User Input User input is allowed only on the following sheets; Cover, Topo Data, and Other G&L. Space for user notes is allowed on the Path Loss and Availability sheets. The various spreadsheets are protected so that the user cannot inadvertently overwrite a formula or a reference. The spreadsheet contains sample data for instructional purposes. The user should overwrite sample data during data entry and delete all other sample data in non-required spreadsheet cells. Cover Sheet: User input areas are generally un-shaded. The revision and hop nomenclature areas at the top contain sample input data and should be overwritten with site specific data. Ensure that the data are entered using the units of measure indicated. In several cases, conversions are calculated for the user's viewing pleasure. Topo Data: User data input is limited to several areas. These are; the twenty (20) elevation points, the average foliage height, the point adder column, and the notes. With regard to the elevation or data points, the elevation data would normally be read from a topographic map such as a USGS 7.5 minute type. For program simplicity, the number of data points requested by the spreadsheet was fixed at twenty, (20), and the distance between the data points is automatically calculated as equidistant based on the total distance between the subject sites. It is recommended that the user select twenty equidistant points along a straight line drawn on the topo map(s) between the two subject sites. Note that the subject site locations are not to be included in the count of the twenty selected data points. The elevation for any particular datum point may be selected "off-center" to accentuate a ridge, peak, or valley. Note: If the path was previously engineered or is known to be good empirically, this step may be bypassed. If bypassed, it is recommended that "dummy" data be entered and a notation be made on the cover sheet.

21362473.xls

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Documentation

For adjustments to elevations based upon man-made objects in or near the path, there is a column for "Point Adder". An example of this is given. See point #12 on the Topo Data sheet and note the effect of this "adder" on the graph. Average foliage height may be adjusted as required; this number is set at 40 feet for a default value. The foliage height will appear as a green trace on the path profile graph. Other Gains & Losses: The "Other G&L" worksheet provides space for estimating additional factors which will affect the Fade Margin, (or Received Signal Level). Note that although an amplifier is listed under "Gains", in most cases, an amplifier would not be acceptable due to the power restrictions imposed on the intentional radiator, (the antenna), by the FCC for the subject ISM bands. 4.0 Calculations and Output The Program provides a path analysis from Site A to Site B. Because of the intended use of this program with regard to service, (ISM), transmitting and receiving equipment at each end will normally be identical with regard to make, model, and performance. If there is a significant difference between power outputs and antenna types between the sites, the user may elect to do the calculation twice, (e.g. "B" to "A"), or use the worst case scenario at Site A. Formulae and reference information is included on the various sheets. Additional reference information is given in Paragraph 4 below. Of most interest to the User is the calculated output data given on the Cover Sheet Line 41 (distance between the sites), Line 44 (Fade Margin), and Line 45 (estimated Availability). Also refer to Lines 9 and 29 for the bearing or azimuth angle from North for the purpose of antenna aiming. The topo data entered provides a full page Profile and a summary profile on the Cover Sheet. 5.0 Summary & References This spreadsheet is intended to document unlicensed spread spectrum hops in the ISM bands. The results obtained will be in close agreement with commercial and vendor supplied programs using the same data although the calculations herein may be slightly more conservative. It is not the purpose of this documentation to teach path analysis - this Program should only be used by qualified personnel with an understanding of radio path analysis. Any suggestions, recommendations, or corrections are welcomed.

References: Conversion Factors

"Handbook of Chemistry & Physics", 59th Edition, CRC Press.

Path Loss Formula

Various Supplier catalogs and Radio Manufacturer support documentation.

Availability Formula (Barnett's Model)

"Engineering Considerations for Microwave Communications Systems", AG Communication System, 4th Edition, 1991, pp. 68-69.

Note: Other calculations are based on simple algebra and spherical trigonometry. Some suggested inputs are based upon the author's experience. Standard spreadsheet functions have been applied, and all formulae are within printable sheet boundaries and in plain view.

21362473.xls

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Documentation