BPSU, Philippines - Microwave Link Communication Design aided using Google Earth

MICROWAVE LINK COMMUNICATION DESIGN

INTRODUCTION In today’s information age, knowledge is made readily available not only through cable or wired connections but also through wireless communications. Knowing your way back in the mountains is no longer a problem with GPS (Global Positioning System). Communicating with family and friends without the use of landline phones is now possible with cellular phones. Exchanging documents can be done in a minute using Bluetooth. Even accessing the internet in a restaurant or while commuting is now a regular thing because of Wi-Fi (Wireless Fidelity). And the one thing they all have in common is that they operate in microwave frequencies.

Microwaves are electromagnetic waves with frequencies that range from approximately 500MHz to 300GHz or more. The prefix "micro-" in "microwave" is not meant to suggest a wavelength in the micrometers range. It only indicates that microwaves are "small" compared to waves used in typical radio broadcasting, falling along 1.0mm to 30cm which are slightly longer than infrared energy.

The main advantage of using microwaves in communications is that it has the capacity to carry thousands of individual information channels between two points without the need for physical facilities such as coaxial cables or optical fibers. It also avoids the need for right-of-way acquisition between properties and are better suited for spanning large bodies of water, going over high mountains, or going through heavily wooded terrain that impose formidable barriers to cable systems. But with these advantages also comes disadvantages. Due to high frequencies employed in microwave systems, it is more difficult to analyze and design circuits and to implement measuring techniques and conventional components. Also, microwave frequencies propagate in a straight line, limiting their use to line-of-sight applications.

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MICROWAVE LINK COMMUNICATION DESIGN Aside from those mentioned earlier, another line-of-sight application for microwaves is a point-to-point communication link. It uses a beam of radio waves in the microwave frequency range to transmit information between two fixed locations on the Earth. A point-to-point microwave communication link is often employed in the form of fixed-link operator, utility private network, TV distribution network and mobile backhaul network among other things.

In the succeeding parts, the group will design a point-to-point microwave communication link with no specific application intended but with communication requirements identified. In this design, the specified points of communication are Dangcol Balanga, Bataan as the receiver site while the transmitter site can be any location at least 25km away from the receiver site. The maximum transmit power is 2W with a receiver IF bandwidth of 10MHz. To meet ―industry standard‖, the performance requirements range per link should be from a minimum of 99.999% availability (about 300seconds outage a year) to 99.9996% (about 125seconds outage a year).

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ACKNOWLEDGMENT The group would like to extend their gratitude and appreciation to the following persons who have shown their support and have been an integral part in the progress and completion of this design.

To Engr. Riadal Sampang, their instructor, for her patience, assistance, and professional guidance in the preparation and completion of this design,

To their family members, for inspiring them to work hard in this project and for understanding and attending to their needs,

To their classmates and friends, for supporting them despite undergoing the same hardships in their own designs,

And above all, to the Almighty God, who bestowed them with intelligence and provide them with the determination to put this design together up to the end.

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TABLE OF CONTENTS INTRODUCTION

1

ACKNOWLEDGMENT

3

TABLE OF CONTENTS

4

OBJECTIVES

5

DESIGN CONSIDERATIONS

6

I SITE SELECTION

6

II ANTENNA HEIGHT

10

III TOWERS IV FIELD SURVEY REPORT V ANTENNA TYPES VI REPEATER VII WAVEGUIDE AND TRANSMISSION LINES

16 22 31 34 36

DESIGN SPECIFICATIONS

40

DESIGN COMPUTATION

41

SYSTEM RELIABILITY

52

SYSTEM FIGURE

53

POWER LEVEL DIAGRAM

55

COST ESTIMATION

56

CONCLUSION

57

GLOSSARY

59

SPECIFICATIONS

60

REFERENCES

69

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OBJECTIVES MAIN OBJECTIVE To design a Point-to-Point Microwave Communication Link with a path length of no less than 25 kilometers from the receiver site (Dangcol, Balanga Bataan) with 4 million pesos (Php 4 000 000) as the allocated budget.

SPECIFIC OBJECTIVES 

Discuss the factors that should be considered in the design of the microwave link.



Select possible receiver, transmitter and if necessary, repeater site locations to provide a path link with line-of-sight (LOS).



Visit site locations to check for land availability and for possible obstructions and their height.



Compute for antenna tower height by considering the effective Earth bulge, land elevation, height of obstructions (e.g. houses, commercial establishments, trees) and Fresnel clearance.



Choose antenna tower based on computed height, land area, and location wind loading.



Choose antenna type and diameter to be used for the transmitting and receiving antennas.



Choose the type of repeater, waveguide and transmission lines to be used.

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

Solve for system reliability and figure and provide a power level diagram.



Provide a tabulated list of the materials including description, specification, and cost.

DESIGN CONSIDERATIONS I.

SITE SELECTION Site selection is the process of choosing the optimal location for an anticipated

use. It involves measuring the needs of a new project against the merits of potential locations. Since microwave communication is a line-of-sight (LOS) communication, the first step in choosing the location of the transmitter and receiver sites is verifying that there are no natural and man-made obstructions between them. In cases where a straight path with no obstructions is unavailable, a repeater can be employed to relay signals over the obstructions so that the signal can cover longer distances.

Microwave terminal sites can be a tower constructed on an existing structure such as building rooftops or a separate tower in an elevated location. In putting up a tower on a building rooftop, the architectural and structural plan of the building should be investigated to determine whether the structure is adequate. The cost of building modifications to accomplish the purpose and the possibility of future building construction along the path must also be taken into consideration. When additional height is required and building structure is unable to support a tower, a separate tower can be erected to mount the antenna fixtures.

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MICROWAVE LINK COMMUNICATION DESIGN For maintenance purposes, the site location should have road access from the nearest improved road to the proposed building location. The site should also have adequate source of power often in the form of commercial electric power of suitable secondary or distribution voltage.

Before visiting every potential terminal site, topographic maps are often used to check the terrains for clear LOS. Topographic maps are detailed, accurate graphic representations of features that appear on the Earth’s surface. These features can be divided into the following categories: 

Culture: roads, buildings, urban development, boundaries, railways, power transmission lines



Hydrography: lakes, rivers, streams, swamps, coastal flats



Relief: mountains, valleys, slopes, depressions



Vegetation: wooded and cleared areas, vineyards and orchards



Toponymy: place names, water feature names, highway names

Since topographic maps are only two or three dimensional representation of the physical environment at a given time, it will never be entirely up to date. Therefore, terrain mapping using topographic maps is a good starting point and is only a prerequisite to a field survey.

In the site selection, the group used Google Earth to check for line-of-sight in choosing potential terminal site locations. Google Earth is a virtual globe, map and geographical information program that maps the Earth by the superimposition of images obtained from satellite imagery, aerial photography and geographic information system (GIS) 3D globe. The baseline resolution of Google Earth is about 15 meters while BSECE5B

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MICROWAVE LINK COMMUNICATION DESIGN the altitude resolution varies by country. Since Google Earth is free and is readily available to students, the group used it as a preliminary tool in the site selection.

In this microwave link communication design, the required receiver site is Dangcol Balanga, Bataan. Since there are no buildings of suitable height to construct a tower on, the group chose an empty lot along a concrete road as the receiver site (14°38'49.37"N, 120°29'57.32"E). After establishing the receiver site, the group selected potential transmitter sites that are at least 25km away from the receiver site as per requirement. The chosen transmitter site is in Prado Siongco, Lubao Pampanga. The transmitter site (14°52'23.54"N, 120°31'27.50"E) is also an empty lot (for reasons the same BSECE5B

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MICROWAVE LINK COMMUNICATION DESIGN as the receiver site) about one kilometer away from a concrete road. Since the transmitter and receiver sites have no line-of-sight, a repeater site is also chosen. The repeater site (14°41'25.74"N, 120°29'2.43"E) is also an empty lot along the road in Capitangan, Abucay Bataan. Given that the three sites have road access, it is assumed that transmission power lines also exist especially if there are street lights. The finality of the selected site locations will be verified in a field survey.

RECEIVER SITE TO TRANSMITTER SITE: 25.2km

REPEATER TO TRANSMITTER

REPEATER TO RECEIVER

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MICROWAVE LINK COMMUNICATION DESIGN II.

ANTENNA HEIGHT The antenna height at each end of the link can be determined by creating a path

profile. A path profile is a graphical representation of the path traveled by the radio waves between the two ends of a link. Together with considering the effects of Earth bulge and Fresnel Zones, it insures that the link is free from obstructions.

EARTH BULGE Microwave Propagation at Free Space

Although the surface of the Earth is curved, a beam of microwave energy tends to travel in a straight line. Thus, over some distance, there is a protuberance called the ―physical Earth bulge‖.

Microwave Propagation at Standard Atmospheric Condition

However, since microwaves propagate in air instead of free space, the beam is normally bent downward a slight amount by atmospheric refraction. Any change in the

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MICROWAVE LINK COMMUNICATION DESIGN amount of beam bending caused by atmospheric conditions can then be expressed as a change in k or effective Earth radius factor.

k-factor

ATMOSPHERIC CONDITION Flat Earth Condition: The refractive signal path arc follows earth curvature

k=∞

exactly, meaning there is no relative change in the curvature between the beam and the Earth. This makes the Earth appear ―flat‖. Sub-standard / Sub-refraction Condition: The refracted signal path deviates

2 k<3

from a straight line, and it arcs in the direction opposite the earth curvature. This makes the Earth looks rounder. Super standard / Super refraction Condition: The refracted signal path

4 k>3

deviates from a straight line, and it arcs in the same direction as the earth curvature. This results in an effective flattening of the Earth Standard Condition: The usual effect of the declining pressure of the atmosphere with height is to bend radio waves down toward the surface of

4 k=3

4 the Earth by a factor of 3. The end result is that the earth can be considered a little bit flatter. It is a very small variation, but sufficient to help microwave engineers to reach unseen sites.

When the effects of atmospheric refraction are combined with physical Earth bulge, a modified profile is produced, known as ―effective Earth bulge.‖ The formula for effective Earth bulge is given as:

Earth bulge(m) =

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d1(km) x d2(km) 12.75k

Earth bulge(ft) =

d1(mi) x d2(mi) 1.5k

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MICROWAVE LINK COMMUNICATION DESIGN Where: d1 and d2 = the distance from each end site k = the effective Earth radius factor

FRESNEL ZONES

A Fresnel zone, named for physicist Augustin-Jean Fresnel, is one of a (theoretically infinite) number of concentric ellipsoids which define volumes in the radiation pattern of a (usually) circular aperture. Fresnel zones result from diffraction by the circular aperture. The cross section of the first (innermost) Fresnel zone is circular. Subsequent Fresnel zones are annular (doughnut-shaped) in cross section, and concentric with the first.

If unobstructed, radio waves will travel in a straight line from the transmitter to the receiver. But if there are reflective surfaces along the path, such as bodies of water or smooth terrain, the radio waves reflecting off those surfaces may arrive either out of phase or in phase with the signals that travel directly to the receiver. Waves that reflect off of surfaces within an even Fresnel zone are out of phase with the direct-path wave and reduce the power of the received signal. Waves that reflect off of surfaces within an BSECE5B

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MICROWAVE LINK COMMUNICATION DESIGN odd Fresnel zone are in phase with the direct-path wave and can enhance the power of the received signal. Sometimes this results in the counter-intuitive finding that reducing the height of an antenna increases the signal-to-noise ratio.

Fresnel provided a means to calculate where the zones are--where a given obstacle will cause mostly in phase or mostly out of phase reflections between the transmitter and the receiver. Obstacles in the first Fresnel zone will create signals with a path-length phase shift of 0 to 180 degrees, in the second zone they will be 180 to 360 degrees out of phase, and so on. Even numbered zones have the maximum phase cancelling effect and odd numbered zones may actually add to the signal power.

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MICROWAVE LINK COMMUNICATION DESIGN To maximize receiver strength, one needs to minimize the effect of obstruction loss by removing obstacles from the radio frequency line of sight (RF LOS). To establish RF LOS, it is necessary to clear 60% of the 1st Fresnel zone boundary, from the signal beam centerline outwards, across the entire signal path. Failure to do so will result in additional signal loss caused by diffraction; the amount of loss will depend on the degree of Fresnel zone encroachment. The formula for Fresnel zone is:

Fn(m) = 17.3√

Fn(ft) = 72.1√

Where: Fn = Specific Fresnel zone radius d1 = Distance from one end of path to reflection point d2 = Distance from reflection point to opposite end of path D = Total length of path f = Frequency in GHz n = number of specific Fresnel zone

The formula for Fresnel clearance is: Fc = 0.6(F1) Where: F1 = First Fresnel Zone

After choosing tentative terminal sites and determining the relative elevation of the terrain, a path profile is prepared next. The path is created by plotting the Earth BSECE5B

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MICROWAVE LINK COMMUNICATION DESIGN Curvature and the Total Height Extended. The Earth Curvature is the elevation profile of the land with the addition of the effects of the Earth Bulge. The Total Height Extended is the Earth Curvature with the addition of the Fresnel Clearance and 15 meters for vegetation. The initial path link is used to plot a line of sight from the transmitter to repeater and from repeater to receiver.

TRANSMITTER TO REPEATER LINK

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MICROWAVE LINK COMMUNICATION DESIGN REPEATER TO RECEIVER LINK

The red triangle in the plot is a representation of the antenna height. The antenna height is calculated by subtracting the Total Height Extended from the Earth’s Elevation. The tentative antenna height for the transmitter, receiver, and repeater (both in Transmitter-Repeater Link and Receiver-Repeater Link) is 15m (approximately 50ft). (Sample calculations will be shown in the final path profile and in the Design Computations).

III. TOWERS Radio

masts

and

towers

are,

support antennas (also known as aerials)

typically,

tall

structures

designed

to

for telecommunications and broadcasting,

including television. The terms "mast" and "tower" are often used interchangeably. However,

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in

structural

engineering

terms,

a

tower

is

a

self-supporting

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MICROWAVE LINK COMMUNICATION DESIGN or cantilevered structure, while a mast is held up by stays or guys. In selecting what type of tower to use, the following should be considered first.



Rigidity - The capability of the tower to hold loads such as antennas and cables prior to construction.



Height - The height of the tower must be enough in order to avoid obstructions.



Wind Loading - The anticipated wind loading has to be identified under harsh and additional loading.



Land Area – The land area will determine the kind of towers that can be employed.



Cost – The cost of the antenna will vary depending on height and wind loading.

These are the parameters that will be considered when choosing what type of tower to use – monopole, self-supporting or guyed towers.

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MICROWAVE LINK COMMUNICATION DESIGN MONOPOLE TOWERS Monopole towers are of a single pole design and are generally used in cellular and personal communication service. They are free standing and are usually built cylindrically or with multiple sides. Monopole towers are often placed on the roofs of tall buildings. Each section of the monopole is welded or bolted together to a height ranging from 30 to 490 feet. The section with the largest diameter is at the bottom of the tower, with each successive section smaller as the tower rises. This decrease in diameter contributes to the low wind resistance of monopole towers compared to other tower types.

SELF-SUPPORTING TOWERS Self-supporting towers have a larger footprint than monopoles, but still requires a much smaller area than guyed towers. These towers tend to be the most expensive to build. Used for television, microwave and power transmission, self-supported towers can have either three or four legs. Built on the ground or on buildings, these towers generally feature a lattice frame design. Self-supporting towers are the strongest and have the greatest resistance to ice and wind loads of any of the three communication tower designs. These towers can range from 30 to 490 feet high.

GUYED TOWERS Guyed towers are lighter and more cost efficient than self-supporting towers where space is inexpensive. For this reason, guyed towers are more often used in rural settings. Three guy wires made of high-strength steel anchor the tower to the ground over an anchor radius equal to 2/3 of the tower’s height. The additional support structure in terms of guy wires are also increase the strength of towers against wind sways.

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MICROWAVE LINK COMMUNICATION DESIGN MONOPOLE

GUYED TOWERS

SELF-SUPPORTED

Rigidity

Low

Moderate

High

Height

Low

High

Moderate

Wind Loading

Low

Moderate - High

High

Land Area Required

Low

High

Low

Moderate

Moderate – High

High

Cost

Since the tentative antenna height is 50ft, a 50ft Self-Supporting Tower for the Transmitter, Repeater and Receiver is considered. The tower footprint for a self-erecting tower is lesser than in guyed towers. This is practical for our application since the land area we chose as transmitter, repeater and receiver sites are limited (as viewed from Google Earth).

Finally, though self-supporting towers tend to be expensive compared to monopole and guyed towers, it has the advantage when it comes to wind loads, knowing that the Philippines experience storms in a regular basis every year.

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In the current wind zone map found in the National Structural Code of the Philippines (NSCP), the maximum speed experienced in Bataan and Pampanga (Zone II) can reach as high as 200kph or 124mph.

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According to Beaufort Wind Scale, (an empirical measure that relates wind speed to observed conditions at sea or on land) this is the wind speed experienced during hurricanes. Therefore, to ensure that the towers will not fail and can withstand the wind speed, a self-supporting tower with its strong wind resistance is chosen for this application.

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MICROWAVE LINK COMMUNICATION DESIGN IV. FIELD SURVEY REPORT Field survey is the collection and gathering of information about a location and is often carried out through observation and measurements. For microwave link design, field survey is done on the path between the transmitter and repeater sites and between repeater and receiver sites. The objectives of the field survey done by the group are the following: 

To verify the availability and size of the land area



To examine the existence and height of obstructions (e.g. buildings and trees) along the path of the signal



To check for transmission power lines in the area



To confirm the accessibility of the road accessibility of the area

The following are the collective observation of the group from the field survey.

RECEIVER 

The receiver site is along the road and is ten meters away from the nearest cemented road with AC transmission line, verifying that the site has road and electric power access.



The maximum vegetation around the chosen receiver site is approximately 15 meters. Aside from trees (vegetation), no other obstructions, man-made or natural is found in the vicinity of the receiver site.



The available land area is about 150 square meters.

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REPEATER 

The chosen repeater site is unavailable because foreign investors are already developing the area. Since another empty lot is found near the area, the group chose that as an alternative repeaters site. Then the group verified for line-ofsight between the repeater and transmitter and between the receiver and repeater using Google Earth. Thus, the repeater site has been moved from (14°41'25.74"N, 120°29'2.43"E) to (14°41'24.76"N, 120°28'56.21"E).

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

The only obstructions in the vicinity of the repeater site are the trees with height of about 12 meters.



The repeater site is along the road and is approximately 15 meters away from the cemented road, ensuring easy road access. The availability of electric power source is also verified by the existence of AC transmission lines along the road.

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

The available land area is about 50 square meters.

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MICROWAVE LINK COMMUNICATION DESIGN TRANSMITTER



Even though the transmitter is 1km away from the nearest cemented road, the group still chose this location as the transmitter site because the road can still be accessed. The road access is a straight, uncemented path where vehicles like jeepneys and small trucks have enough room to travel. AC transmission lines along the road also ensures electric power source.



The surroundings of the transmitter site was composed of farms, poultry, piggery, and farm to market roads but the highest obstruction are still those of trees which are about 15 meters.



The available land area is 50 square meters.

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MICROWAVE LINK COMMUNICATION DESIGN source. The path profile is also verified not only from obstructions due to the Earth’s natural elevation (Google Earth) but also through the observation and verification of obstruction by other obstructions like tress, buildings and other structure. The changing of repeater location also resulted to a new path profile and antenna height.

TRANSMITTER TO REPEATER LINK d1 (km)

d2 (km)

Elevation (m)

Earth Bulge (m)

Earth Curvature (m)

Fresnel Radius (m)

Fresnel Clearance (m)

Vegetation (m)

Total Height Extended (m)

0.00

20.90

9.00

0.00

9.00

0.00

0.00

0.00

9.00

0.50

20.40

9.00

1.07

10.07

4.78

2.87

15.00

27.93

1.00

19.90

8.00

2.08

10.08

6.67

4.00

15.00

29.08

1.50

19.40

7.00

3.04

10.04

8.07

4.84

15.00

29.88

2.00

18.90

7.00

3.95

10.95

9.20

5.52

15.00

31.47

2.50

18.40

6.00

4.81

10.81

10.15

6.09

15.00

31.90

3.00

17.90

6.00

5.62

11.62

10.96

6.58

15.00

33.19

3.50

17.40

6.00

6.37

12.37

11.67

7.00

15.00

34.37

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MICROWAVE LINK COMMUNICATION DESIGN 4.00

16.90

7.00

7.07

14.07

12.30

7.38

15.00

36.45

4.50

16.40

7.00

7.72

14.72

12.85

7.71

15.00

37.43

5.00

15.90

8.00

8.31

16.31

13.34

8.00

15.00

39.32

5.50

15.40

14.00

8.86

22.86

13.77

8.26

15.00

46.12

6.00

14.90

16.00

9.35

25.35

14.14

8.49

15.00

48.84

6.50

14.40

18.00

9.79

27.79

14.47

8.68

15.00

51.47

7.00

13.90

20.00

10.18

30.18

14.76

8.85

15.00

54.03

7.50

13.40

25.00

10.51

35.51

15.00

9.00

15.00

59.51

8.00

12.90

33.00

10.79

43.79

15.20

9.12

15.00

67.91

8.50

12.40

37.00

11.02

48.02

15.36

9.21

15.00

72.24

9.00

11.90

42.00

11.20

53.20

15.48

9.29

15.00

77.49

9.50

11.40

44.00

11.33

55.33

15.57

9.34

15.00

79.67

10.00

10.90

49.00

11.40

60.40

15.62

9.37

15.00

84.77

10.50

10.40

56.00

11.42

67.42

15.63

9.38

15.00

91.80

11.00

9.90

61.00

11.39

72.39

15.61

9.37

15.00

96.75

11.50

9.40

69.00

11.30

80.30

15.55

9.33

15.00

104.64

12.00

8.90

75.00

11.17

86.17

15.46

9.28

15.00

110.44

12.50

8.40

77.00

10.98

87.98

15.33

9.20

15.00

112.18

12.90

8.00

80.00

10.79

90.79

15.20

9.12

15.00

114.91

13.20

7.70

62.00

10.63

72.63

15.08

9.05

15.00

96.68

13.50

7.40

85.00

10.45

95.45

14.95

8.97

15.00

119.42

14.00

6.90

101.00

10.10

111.10

14.70

8.82

15.00

134.92

14.50

6.40

111.00

9.70

120.70

14.41

8.65

15.00

144.35

15.00

5.90

121.00

9.25

130.25

14.07

8.44

15.00

153.70

15.50

5.40

135.00

8.75

143.75

13.69

8.21

15.00

166.96

16.00

4.90

130.00

8.20

138.20

13.24

7.95

15.00

161.15

16.50

4.40

144.00

7.59

151.59

12.75

7.65

15.00

174.24

17.00

3.90

142.00

6.93

148.93

12.18

7.31

15.00

171.24

17.50

3.40

139.00

6.22

145.22

11.54

6.92

15.00

167.15

18.00

2.90

130.00

5.46

135.46

10.81

6.48

15.00

156.94

18.50

2.40

119.00

4.64

123.64

9.97

5.98

15.00

144.62

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1.90

137.00

3.78

140.78

8.99

5.39

15.00

161.17

19.50

1.40

151.00

2.85

153.85

7.82

4.69

15.00

173.54

20.00

0.90

190.00

1.88

191.88

6.35

3.81

15.00

210.69

20.50

0.40

225.00

0.86

225.86

4.28

2.57

15.00

243.43

20.90

0.00

257.00

0.00

257.00

0.00

0.00

0.00

257.00

RECEIVER TO REPEATER LINK Earth Bulge (m)

Earth Curvature (m)

Fresnel Radius (m)

Fresnel Clearance (m)

Vegetation (m)

Total Height Extended (m)

d1(km)

d2(km)

Elevation (m)

0.00

5.14

66.00

0.00

66.00

0.00

0.00

0.00

66.00

0.50

4.64

62.00

0.24

62.24

4.59

2.76

15.00

80.00

1.00

4.14

84.00

0.43

84.43

6.14

3.68

15.00

103.12

1.50

3.64

87.00

0.57

87.57

7.05

4.23

15.00

106.80

2.00

3.14

93.00

0.66

93.66

7.56

4.54

15.00

113.19

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2.64

114.00

0.69

114.69

7.75

4.65

15.00

134.34

3.00

2.14

124.00

0.67

124.67

7.64

4.59

15.00

144.26

3.50

1.64

135.00

0.60

135.60

7.23

4.34

15.00

154.94

4.00

1.14

155.00

0.48

155.48

6.44

3.86

15.00

174.34

4.50

0.64

181.00

0.30

181.30

5.12

3.07

15.00

199.37

5.00

0.14

228.00

0.07

228.07

2.52

1.51

15.00

244.59

5.14

0.00

257.00

0.00

257.00

0.00

0.00

0.00

257.00

Based on plotted values of Earth Elevation, Earth Bulge, Fresnel Clearance, and Vegetation, the new antenna and tower heights are determined by drawing a line-ofsight on the graph.

ANTENNA HEIGHT

TOWER HEIGHT

TRANSMITTER

20 meters

70 feet

REPEATER

20 meters

70 feet

RECEIVER

30 meters

100 feet

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MICROWAVE LINK COMMUNICATION DESIGN V.

ANTENNA TYPES Microwave antenna is a type of antenna which is operated at microwave

frequencyand they are widely used in many practical applications .A microwave antenna is a major system component that allows a microwave system to transmit and receive data between microwave sites. A microwave antenna is located at the top of a tower at each microwave site. Microwaves are radio waves with wavelengths ranging from as long as one meter to as short as one millimeter. Microwave antennas are widely used in various applications such as Televisions, and telephone communications are transmitted between ground stations and to and from satellites.

Antenna is an important part of any wireless communication system as it converts the electronic signals into Electromagnetic. The IEEE Standard Definitions of Terms (IEEE Std 145-1983) for antenna is any device that converts electronic Signals to electromagnetic waves (and vice versa), effectively with minimum loss of signals.

CLASSIFICATION OF MICROWAVE ANTENNA 1. MICRO STRIP PATCH ANTENNAS Microstrip antennas are attractive due to their light weight, conformability and low cost. These antennas can be integrated with printed strip-line feed networks and active devices. A major contributing factor for recent advances of microstrip antennas is the current revolution in electronic circuit miniaturization brought about by developments in large scale integration. As conventional antennas is often bulky and costly part of an electronic system, micro strip antennas based on photolithographic technology. Its typical applications are on Global Positioning System, Paging, Cellular Phone, and Personal Communication System.

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MICROWAVE LINK COMMUNICATION DESIGN 2. PLASMA ANTENNAS A plasma antenna is a column of ionized gas in which the free electrons emit, Absorb and reflect radio signals just as the free electrons in a metal antenna. The plasma antenna can be made to appear and disappear in milliseconds. The plasma antenna has an adjustable high frequency cut off. It can transmit and receive low frequency signals while not interacting with high frequency signals. It is primarily use for high speed digital communication, radar systems, radio antenna, 4G, RFID, and Digital Home.

3. MIMO (Multiple-input and Multiple-output) ANTENNAS It uses multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology. it offers significant increases in data throughput and link range without additional bandwidth or increased transmit power. It achieves this goal by spreading the same total transmit power over the antennas to achieve an array gain that improves the spectral efficiency or to achieve a diversity gain that improves the link reliability. It is usually used in WLAN – WiFi 802.11n, Mesh Networks , WMAN – WiMAX 802.16e ,and RFID

4. HORN ANTENNAS

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MICROWAVE LINK COMMUNICATION DESIGN Horn antennas are highly suitable for frequencies where waveguides are the standard feed method, as they consist essentially of a waveguide whose end walls are flared outwards to form a megaphone-like structure. In the case illustrated, the aperture is maintained as a rectangle, but circular and elliptical versions are also possible. The dimensions of the aperture are chosen to select an appropriate resonant mode, giving rise to a controlled field distribution over the aperture. The best patterns (narrow main lobe, low side lobes) are produced by making the length of the horn large compared to the aperture width, but this must be chosen as a compromise with the overall volume occupied. A common application of horn antennas is as the feed element for parabolic dish antennas in satellite systems

Horn antennas are extensively used at microwave frequencies when the power gain needed is moderate. For high power gains other antennas like lines or parabolic reflectors are preferred rather than horn antennas.

5. PARABOLIC ANTENNA A parabolic antenna is an antenna that uses a parabolic reflector, a curved surface with the cross-sectional shape of a parabola, to direct the radio waves. The most common form is shaped like a dish and is popularly called a dish antenna or parabolic dish. The main advantage of a parabolic antenna is that it has high directivity. It functions similarly to a searchlight or flashlight reflector to direct the radio waves in a narrow beam, or receive radio waves from one particular direction only. Parabolic antennas have some of the highest gains, that are they can produce the narrowest beam widths, of any antenna type. In order to achieve narrow beam widths, the parabolic reflector must be much larger than the wavelength of the radio waves used, so parabolic antennas are used in the high frequency part of the radio spectrum, at UHF and microwave frequencies, at which the wavelengths are small enough that BSECE5B

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MICROWAVE LINK COMMUNICATION DESIGN conveniently-sized reflectors can be used. Horn antennas are extensively used at microwave frequencies when the power gain needed is moderate. For high power gains other antennas like lines or parabolic reflectors are preferred rather than horn antennas.

Applications 

Point-to-point communications



In applications such as microwave relay links that carry telephone and television signals between nearby cities, WAN/LAN links for data communications, satellite communications and spacecraft communication antennas.



They are also used in radio telescopes

In this design, parabolic dish with parabolic reflector will be used to provide high power gain which is important in a point-to-point microwave communications system.

VI. REPEATER

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MICROWAVE LINK COMMUNICATION DESIGN A wireless repeater allows point to point wireless links, also referred to as pointto-point wireless, to cover greater distances and get around obstructions that may limit line of sight (LOS). Wireless repeaters are also used to provide a greater signal level where needed and for wireless repeaters it could be either be passive or active repeater.

A passive radio link deflection, or passive repeater is a plant that implements a microwave link, in places where an obstacle in the signal path blocks any direct, line of sight microwave link and essentially beam benders while active repeaters receives and transmits radio device installed at intermediate points in radio communications links, designed to amplify received signals and then retransmit them farther along the link.

Passive repeaters have the following advantages over active sites: 

No power is required



No regular road access is required



No equipment housing is needed



They are environmentally friendly



Little or no maintenance is required

In many cases it is not possible, practical, or allowable to use a passive repeater an active repeater will be required to use. Active repeaters receive and transmit radio device installed at intermediate point in the radio communications link. It is designed to amplify received signals and then transmit them farther along the link. The basic types of active microwave repeaters are the following. 

IF Repeater / Heterodyne Repeater – the received the RF carrier is downconverted to an IF frequency, amplified, reshaped, up-converted to an RF frequency and then retransmitted.

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

Baseband Repeater – the received RF carrier is down-converted to an IF frequency, amplified, filtered, and then further demodulated to baseband. The baseband signal, which is typically frequency-division multiplexed voice-band channels is further demodulated to a master group, a subgroup, group or even channel level. Once the baseband signal has been configured, it FM modulates the IF carrier, which is up-converted to an RF carrier and then retransmitted



RF Repeater – the received microwave signal is not down-converted to IF or baseband; it simply mixed (heterodyned) with a local oscillator frequency in a nonlinear mixer. The radio signal is simply converted in frequency and then reamplified and transmitted to the next down-line repeater or terminal station. Reconfiguring and reshaping are not possible.

The group used active RF repeaters in this design to increase the gain of the system. Since RF repeaters doesn’t demodulate the received signals it also used less components compared to IF or baseband repeaters.

VII. WAVEGUIDE AND TRANSMISSION LINES The purpose of the transmission line (feeder) in this context is to transfer the RF signal from the transmit module of the radio equipment to the antenna system in the most efficient manner. For equipment configurations that have the RF unit at the back of the antenna, the feeder is used to carry the baseband and IF signals plus the power and telemetry signals. There are two main types of transmission lines used in microwave systems: coaxial cables and waveguides.

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MICROWAVE LINK COMMUNICATION DESIGN COAXIAL CABLE Coaxial cable is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880. Coaxial cable differs from other shielded cable used for carrying lowerfrequency signals, such as audio signals, in that the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a radio frequency transmission line.

Cable loss is a function of the cross-sectional area; therefore, the thicker the cable, the lower the loss. Obviously the disadvantage of thicker cables is the reduced flexibility and increased cost. Cable loss is quoted in decibels per 100m. Air dielectric cables offer a low-loss solution, but have the added complexity of pressurization to keep moisture out.

As the frequency of operation increases, the resistance of the conductor increases, resulting in power loss due to heating. Any alternating current does not have a uniform current density. The current density tends to be greater at the surface of the conductor, which is a phenomenon known as the skin effect. At gigahertz frequencies, this change in resistance can be large. The conductor loss per 100m thus increases as frequency increases.

WAVEGUIDE Microwave energy can be guided in a metallic tube—called a waveguide—with very low attenuation. The electric and magnetic fields are contained within the guide, and therefore there is no radiation loss. Furthermore, since the dielectric is air, the BSECE5B

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MICROWAVE LINK COMMUNICATION DESIGN dielectric losses are negligibly small. A waveguide will only operate between two limiting frequencies, called the cutoff frequency. These frequencies depend on the waveguide geometry compared to the wavelength of operation. The waveguides must be chosen within the frequency band that supports the desired mode of propagation. There are three types of waveguides: rectangular, circular and elliptical.

RECTANGULAR WAVEGUIDE As shown in the given diagram, the rectangular wave guide is designed from conducting material in rectangular shape which is hollow from the center and fully polished from interior. The outer surface of the wave guide is coded with insulating material or paint in order to avoid dust and rust. These types of wave guides are available in different lengths and sizes in order to fulfill the requirements of the circuit.

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MICROWAVE LINK COMMUNICATION DESIGN CIRCULAR WAVEGUIDE As shown in the given diagram the circular waveguide is designed from a conducting pipe which is hollow from the center and polished from interior portion. The outer surface of the wave guide is coded with the insulated paint in order to avoid dust and rust. These types of wave guide are available in different lengths and sizes in order to fulfill the requirement of the circuit.

ELLIPTICAL WAVEGUIDE The most common waveguide used in a microwave radio installation is the elliptical waveguide. This has corrugated copper walls with a plastic sheath for protection. The corrugations result in a strong cable with limited bending ability. The limitation on bending is specified in terms of a bending radius in the E-plane and the Hplane. A much smaller bending radius is allowed in the E-plane; therefore, one should utilize this when planning a waveguide installation. Although a maximum twist allowance is specified, twists should be avoided when planning an installation. A change in plane from E to H can easily be achieved within a few meters without twisting the waveguide by bending the waveguide within the specified bending radius of each E- and H-plane, respectively. The effective usable length of waveguide is determined by the loss of waveguide. The waveguide loss is specified in decibels per 100m and increases significantly as frequency increases. Above 10 GHz, the loss becomes excessive and radio manufacturers often offer the choice of a baseband or IF connection to an outdoor RF unit mounted on the tower to avoid long lossy waveguide runs.

The type of transmission line that will be used in this design is waveguide because the transmission losses in waveguides are less than that of coaxial cables. The BSECE5B

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MICROWAVE LINK COMMUNICATION DESIGN specific kind of waveguide that will be used is elliptical waveguide because it is the most common type of waveguide used in microwave applications.

DESIGN SPECIFICATIONS TRANSMITTER TO REPEATER LINK LOCATION

Prado Siongco

Capitangan

LATITUDE

14°52'23.54"N

14°41'24.76"N

LONGITUDE

120°31'27.50"E

120°28'56.21"E

ELEVATION

9 meters

257 meters

TOWER TYPE

Self-Supporting

Self-Supporting

70 feet

70 feet

TOWER HEIGHT

20.90 kilometers

PATH DISTANCE

REPEATER TO RECEIVER LINK LOCATION

Capitangan

Dangcol

LATITUDE

14°41'24.76"N

14°38'49.37"N

LONGITUDE

120°28'56.21"E

120°29'57.32"E

ELEVATION

257 meters

66 meters

TOWER TYPE

Self-Supporting

Self-Supporting

70 feet

100 feet

TOWER HEIGHT PATH DISTANCE

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5.14 kilometers

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DESIGN COMPUTATIONS 1. Transmitter Power (PT) PT PT(dbW) = 10log 1W

PT PT(dbm) = 10log 1mW

2. Transmitter Waveguide Loss (LT) α(dB) LTx(db) = length x total length 3. Transmitter Parabolic Dish Antenna Gain (GT) GT(db) = 17.8 + 20logfGHz + 20logD(m)

GT(db) = 7.5 + 20logfGHz + 20logD(ft)

4. Effective Isotropic Radiated Power (EIRP) EIRP(watts) =

P T x GT LT

EIRP(dB) = PT(dBm) + GT(dB) – LT(dB)

5. Free Space Loss (FSL) – The loss incurred by an electromagnetic wave as it propagates in a straight line through vacuum with no absorption or reflection from nearby objects. FSL (db) = 92.4 + 20logfGHz + 20logD(km)

FSL (db) = 96.6 + 20logfGHz + 20logD(mi)

6. Isotropic Receive Level (IRL) IRL(dBW) = EIRP(dBW) – FSL(dB)

IRL(dBm) = EIRP(dBm) – FSL(dB)

7. Receiver Waveguide Loss (LRx) α(dB) LRx(db) = length x total length 8. Receiver Parabolic Dish Antenna Gain(GR) GR(db) = 17.8 + 20logfGHz + 20logD(m)

GR(db) = 7.5 + 20logfGHz + 20logD(ft)

9. Received Signal Level (RSL) RSL(dBW) = IRL(dbW) + GR(dB) – LRx(dB)

RSL(dBm) = IRL(dbm) + GR(dB) – LRx(dB)

10. Noise Threshold (N)

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N(dBW) = -204 + 10logB + NF(dB)

N(dBm) = -174 + 10logB + NF(dB)

11. FM Improvement Threshold (IT) – The point where ―capture-effects‖ takes place and the output signal-to-noise ratio suddenly jumps to 30dB. IT(dBW) = N(dBW) + 10dB

IT(dBm) = N(dBm) + 10dB

12. Fade Margin (FM) – A ―fudge factor‖ included in the system gain equation that considers the non-ideal and less predictable characteristics of radio-wave propagation, such as multipath propagation and terrain sensitivity. (Interpolation of Rayleigh Table) FM(dB) = RSL(dBW) – IT(dBW)

FM(dB) = RSL(dBm) – IT(dBm) RAYLEIGH TABLE

PROPAGATION RELIABILITY

FADE MARGIN(DB)

90

8

99

18

99.9

28

99.99

38

99.999

48

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TRANSMITTER TO REPEATER LINK SAMPLE COMPUTATION

Effective Earth Bulge Eb(m) =

d1(km) x d2(km) 1O x 10.9 = 4 12.75k 12.75 x 3

Eb(m) = 6.41m

First Fresnel Zone F1(m) = 17.3√

= 17.3√

F1(m) = 15.62m

Fresnel Clearance Fc = 0.6(F1) = 0.6(15.62m) Fc = 9.372m

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MICROWAVE LINK COMMUNICATION DESIGN POWER CALCULATION

Transmitter Power PT 2W PT(dbm) = 10log 1mW = 10log 1mW PT(dbm) = 33.01dBm

Transmitter Waveguide Loss α(dB) LT(db) = length x total length 4.56dB 3.2808 = 100ft x (20m + 2.5m) x m LT(db) = 3.37dB

Transmitter Antenna Gain GT(db) = 7.5 + 20logfGHz + 20logD(ft) = 7.5 + 20log(6.4) + 20log(6) GT(db) = 39.19dB

Effective Radiated Power EIRP(dB) = PT(dBm) + GT(dB) – LT(dB) EIRP(dB) = 33.01dBm + 39.19dB – 3.37dB EIRP(dB) = 68.83dBm

Free Space Loss FSL(db) = 92.4 + 20logfGHz + 20logD(km) FSL(db) = 92.4 + 20log(6.4) + 20log(20.9) FSL(db) = 134.93dB BSECE5B

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Isotropic Receive Level IRL(dBm) = EIRP(dBm) – FSL(dB) IRL(dBm) = 68.83dBm – 134.93dB IRL(dBm) = -66.10dBm

Receiver Waveguide Loss α(dB) LRx(db) = length x total length 4.56dB 3.2808 LRx(db) = 100ft x (20m + 2.5m) x m LRx(db)

= 3.37dB

Receiver Parabolic Dish Antenna Gain GR(db) = 7.5 + 20logfGHz + 20logD(ft) = 7.5 + 20log(6.4) + 20log(6) GR(db) = 39.19dB

Receives Signal Level RSL(dBm) = IRL(dbm) + GR(dB) – LRx(dB) RSL(dBm) = -66.10dBm + 39.19dB – 3.37dB RSL(dBm) = -30.28dBm

Noise Threshold N(dBm) = -174 + 10logB + NF(dB) N(dBm) = -174 + 10log(10x106) + 10dB N(dBm) = -94dBm

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FM Improvement Threshold IT(dBm) = -94dBM) + 10dB IT(dBm) = -84dBm

Fade Margin FM(dB) = RSL(dBm) – IT(dBm) FM(dB) = -30.28dBm –(-84dBm) FM(dB) = -30.28dBm + 84dBm FM(dB) = 53.72dBM

Propagation Reliability 48

99.999

53.72

R

58

99.9999

BSECE5B

58-53.72 99.9999 - R = 99.9999-99.999 58-48 R = 99.9995%

Page 46


REPEATER TO RECEIVER LINK SAMPLE COMPUTATION

Effective Earth Bulge Eb(m) =

d1(km) x d2(km) 2.5 x 2.64 = 4 12.75k 12.75 x 3

Eb(m) = 0.39m

First Fresnel Zone F1(m) = 17.3√

= 17.3√

F1(m) = 7.75m

Fresnel Clearance Fc = 0.6(F1) = 0.6(7.75m) Fc = 4.65m

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MICROWAVE LINK COMMUNICATION DESIGN POWER CALCULATION

Transmitter Power PT(dbm) = Transmitter to Repeater Link RSL(dBM) PT(dbm) = -30.28dBm

Transmitter Waveguide Loss α(dB) LT(db) = length x total length 4.56dB 3.2808 = 100ft x (17.5m + 2.5m) x m LT(db) = 2.99dB

Transmitter Antenna Gain GT(db) = 7.5 + 20logfGHz + 20logD(ft) = 7.5 + 20log(6.4) + 20log(4) GT(db) = 35.66dB

Active Repeater Antenna Gain GRpt(db)= 63dB (Antenna specification)

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Effective Radiated Power EIRP(dB) = PT(dBm) + GT(dB)

+

GRpt(db) – LT(dB)

EIRP(dB) = -30.28dBm + 35.66dB + 63dB – 2.99dB EIRP(dB) = 65.39dBm

Free Space Loss FSL(db) = 92.4 + 20logfGHz + 20logD(km) FSL(db) = 92.4 + 20log(6.4) + 20log(5.14) FSL(db) = 122.74dB

Isotropic Receive Level IRL(dBm) = EIRP(dBm) – FSL(dB) IRL(dBm) = 65.39dBm – 122.74dB IRL(dBm) = -57.35dBm

Receiver Waveguide Loss α(dB) LRx(db) = length x total length 4.56dB 3.2808 LRx(db) = 100ft x (30m + 2.5m) x m LRx(db) = 4.86dB

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Receiver Parabolic Dish Antenna Gain GR(db) = 7.5 + 20logfGHz + 20logD(ft) = 7.5 + 20log(6.4) + 20log(2) GR(db) = 29.64dB

Receives Signal Level RSL(dBm) = IRL(dbm) + GR(dB) – LRx(dB) RSL(dBm) = -57.35dBm + 29.64dB – 4.86dB RSL(dBm) = -32.57dBm

Noise Threshold N(dBm) = -174 + 10logB + NF(dB) N(dBm) = -174 + 10log(10x106) + 10dB N(dBm) = -94dBm

FM Improvement Threshold IT(dBm) = -94dBM) + 10dB IT(dBm) = -84dBm

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Fade Margin FM(dB) = RSL(dBm) – IT(dBm) FM(dB) = -32.57dBm –(-84dBm) FM(dB) = -32.57dBm + 84dBm FM(dB) = 53.72dBM

Propagation Reliability 48

99.999

51.43

R

58

99.9999

BSECE5B

58-51.43 = 58-48

99.9999 - R 99.9999-99.999

R = 99.9993%

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SYSTEM RELIABILITY System reliability is the percentage of time a system or link meets performance requirements. R = (1 – Unavailability) x 100%

U = (1 – Availability) x 100%

UTotal = U1 + U2 + U3 … + UN

PROPAGATION RELIABILITY / AVAILABILITY Transmitter to Repeater

99.9995%

Repeater to Receiver

99.9993%

UTx-Rpt = 1 – 0.999995 = 0.000005 URpt-Rx = 1 – 0.999993 = 0.000007 UTotal = UTx-Rpt + URpt-Rx = 0.000005 + 0.000007 = 0.000012 RTotal = (1 – UTotal) x 100% = (1 – 0.000012) x 100% = 99.9988% SYSTEM RELIABILITY = 99.9988%

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SYSTEM FIGURE

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POWER LEVEL DIAGRAM

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COST ESTIMATION DESCRIPTION

QUANTITY

PRICE

1 Tower

301,955.06Php

1 Tower

342,436.95Php

1 Tower

606,078.01Php

2 Antennas

234,133.96Php

1 Antenna

128,673.12Php

1 Antenna

747,68.94Php

320 feet

261,632.45Php

Transmitter Site Land Area

30 square meter

45, 000Php

Repeater Site Land Area

30 square meter

30, 000Php

Receiver Site Land Area

40 square meter

20, 000Php

Transmitter Tower T-36 70’ Medium Self Supporting Tower Kit Repeater Tower T-36 70’ Heavy Self Supporting Tower Kit Receiver Tower T-48 100’ Medium Self Supporting Tower Kit Transmitter and Repeater Antenna Radio Waves SP6-59RS Repeater Antenna CommScope P4-57W-PXA Receiver Antenna CommScope P257W-PXA Waveguide RFS Cablewave EP65-STANDARD

TOTAT AMOUNT:

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2,044,678.49

Page 56


CONCLUSION The following are the conclusion after the design of Point-to-Point Microwave Communication Link with a path length of no less than 25 kilometers from the receiver site (Dangcol, Balanga Bataan) with 4 million pesos (Php 4 000 000) as the allocated budget:

The factors that could affect the point to point microwave system are site selection, antenna height, antenna type, tower type, site survey, repeater, waveguide and transmission line.

The strategic location of the transmitter is on (14°52'23.54"N, 120°31'27.50"E) Prado Siongco Lubao, Pampanga while the receiver is on (14°38'49.37"N, 120°29'57.32"E) Dangcol Balanga, Bataan. Since there is no line-of-sight between the transmitter and receiver,

a

repeater

located

at

Capitangan

Abucay,

Bataan

(14°41'24.76"N,

120°28'56.21"E) was employed.

From site survey, the availability and the obstruction was determined in which the primary obstructions where the trees and other vegetation with a maximum height of 15m

The measured antenna height considering the earth bulge, land elevation, height of the obstructions and Fresnel clearance was 20m for the repeater and transmitter and 30m for the receiver.

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MICROWAVE LINK COMMUNICATION DESIGN Self-supporting tower with its strong wind resistance for the three (3) towers was selected to be used for the transmitter, repeater and receiver.

The determined antenna type to be use was Parabolic Dish Antenna with 6ft diameter on the transmitter and front repeater and 4ft diameter on the back repeater while 2ft diameter on the receiving antenna.

The chosen repeater was active repeater because it is not possible, practical, or allowable to use a passive repeater on the chosen location and the transmission line used is a waveguide because the transmission losses in waveguides are less than that of coaxial cables.

The overall system reliability of the designed point - to - point microwave communication link is based from the computed result was 99.9993% which meet the industry standard of 99.999% availability (about 300 seconds outage a year) to 99.9996% (about 125seconds outage a year).

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GLOSSARY Earth Bulge - It refers to the circular segment of earth profile which blocks off long distance communications.

Fade Margin – A ―fudge factor‖ included in the system gain equation that considers the non-ideal and less predictable characteristics of radio-wave propagation, such as multi-path propagation and terrain sensitivity.

Fresnel Clearance – It is 60% of the first Fresnel zone. In microwave communication design, once the Fresnel Clearance is freed of obstruction, free space loss can be assumed.

Fresnel Zone – It is one of a (theoretically infinite) number of concentric ellipsoids which define volumes in the radiation pattern of a (usually) circular aperture.

Microwaves – A type of an electromagnetic wave whose wavelength ranges from 1.0mm to 30cm.

Repeater – It is an electronic device that receives a signal and retransmits it at a higher level or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances.

System Reliability – The percentage of time a system or link meets performance requirements.

Waveguide - A waveguide is a structure that guides waves, such as electromagnetic waves or sound waves. In electromagnetics and communications engineering, the term waveguide may refer to any linear structure that conveys electromagnetic waves between its endpoints.

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SPECIFICATION TRANSMITTER TOWER ► T-36 70’ Medium Self Supporting Tower Kit REPEATER TOWER ► T-36 70’ Heavy Self Supporting Tower Kit

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RECEIVER TOWER ► T-48 100’ Medium Self Supporting Tower Kit

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TRANSMITTER and REPEATER ANTENNA ► Radio Waves SP6-59RS

alpha frequency

6 GHz

front-to-back ratio (dB)

46 dB

mounting hdw included (Y/N)

Y

maximum power input (W)

N/A

polarization

horizontal or vertical

lightning protection

DC ground

vertical tilt (deg)

0 deg

antenna diameter (ft)

6'

radome (Y/N)

N

antenna size range

6 ft to 7.9 ft

frequency range

5150-5949

dB gain range

30.0 to 39.9

gain

39.2 dBi

frequency (bandwidth)

5.725-6.425 GHz

VSWR

<1.37:1

connector

CPR137G

wind survival w/o ice (MPH)

125 MPH

beamwidth (deg)

1.9 deg

Depth

77"

Width

20"

Height

80"

Weight

230 LB

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ACTIVE REPEATER

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REPEATER ANTENNA ► CommScope P4-57W-PXA/A

alpha frequency

6 GHz


40 dB


Y


150W

polarization



DC ground

vertical tilt (deg)

0 deg


4'

radome (Y/N)

Y

antenna size range

3.5 ft to 5 ft

frequency range

5950-7125

dB gain range

30.0 to 39.9

gain

35. dBi


5.725-6.425 GHz

VSWR

<1.1:1

connector

CPR137G


125 MPH

beamwidth (deg)

2.9 deg

Depth

58"

Width

56"

Height

56"

Weight

370"

BSECE5B

Page 66


RECEIVER ANTENNA ► CommScope P2-57W-PXA

alpha frequency

6 GHz


40 dB


Y


150W

polarization



DC ground

vertical tilt (deg)

0 deg


2'

radome (Y/N)

N

antenna size range

2 ft to 3 ft

frequency range

5950-7125

dB gain range

20.0 to 29.9

gain

29.3 dBi


5.725-6.425 GHz

VSWR

<1.10:1

connector

CPR137G


125 MPH

beamwidth (deg)

5.8 deg

Depth

27.6"

Width

27.6"

Height

24.8"

Weight

41 LB

BSECE5B

Page 67


WAVEGUIDE ► RFS Cableware EP65-STANDARD

type

standard

maximum frequency range

5.90-7.125 GHz

min. bend radius w/o rebend E

7.9"

min.bend radius w/o rebend H

19.8"

min.bend radius w/ rebend E

11.9"

min. bend radius w/ rebend H

23.7"

attenuation, (dB/100'@)

[email protected] GHz





Depth

1.26"

Width

2"

Height

12"

Weight

0.67 LB

BSECE5B

Page 68


REFERENCES BOOK AND ARTICLE REFERENCES      

Microwave Radio Transmission Design Guide Second Edition By Trevor Manning Electronic Communications System Eight Edition By Wayne Tomasi Engineering Considerations for Microwave Communications System By Rober F. White Microwave Network Design: A Manager's Guide to the Engineering Process By Pinnacle Telecom Group Tashjian Towers Corporation Corporation 2013 Catalog By Tashjian Towers Corporation Fundamentals of Radio Link Engineering By J. Frank Jimenez

WEB REFERENCES 

http://financialdictionary.thefreedictionary.com/site+selection



http://en.wikipedia.org/wiki/Site_selection



http://www.ga.gov.au/scientific-topics/geographic information/topographic-maps-data/basics/what-is-atopographic-map



http://docstore.mik.ua/univercd/cc/td/doc/product/wireless/bbf w/ptop/p2pspg02/spg02ch2.htm



http://earthsci.org/education/fieldsk/topmap.htm



http://www.oly-tech.com/antennaheight.html



http://en.wikipedia.org/wiki/Google_Earth



http://en.wikipedia.org/wiki/Beaufort_scale



http://en.wikipedia.org/wiki/Path_profile

BSECE5B

Page 69

BPSU, Philippines - Microwave Link Communication Design aided using Google Earth

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