AMA Computer University Quezon City Campus COLLEGE OF ENGINEERING MICROWAVE LINK DESIGN A DESIGN SUBMITTED TO ENGR. ANTIPAS TEOLOGO JR. IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE SUBJECT ECEG11A – EC SUBMITTED BY: CALDERON, Leonard Andre’ MANALO, April Gray MORTALLA, Anjo PEGUIT, Jan Anthony 3 nd Trimester 2009-2010
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AMA Computer University
Quezon City Campus
COLLEGE OF ENGINEERING
MICROWAVE LINK DESIGN
A
DESIGN
SUBMITTED TO
ENGR. ANTIPAS TEOLOGO JR.
IN
PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE SUBJECT
ECEG11A – EC
SUBMITTED BY:
CALDERON, Leonard Andre’
MANALO, April Gray
MORTALLA, Anjo
PEGUIT, Jan Anthony
3nd
Trimester 2009-2010
Microwave Link Design
ECEG11A – EC
TABLE OF CONTENTS
PRELIMINARY PAGES:
Letter of Transmittal …………………………………………………………………………………………… i
Approval Sheet ……………………………………………………………………………………………………. ii
Acknowledgement …………………………………………………………………………………………….… iii
Dedication ……………………………………………………………………………………………….………….. iv
Company Logo …………………………………………………………………………………………………….. v
CHAPTER 1: A. Objectives ……………………………………………….…………….…….……….… 2
B. Foreword to the Design ……….………………………………...….............. 3
C. Scopes and Limitations ……………………………………..………………..….. 4
D. Significance of the Study …………………………..…………………….…….. 5
E. Review of Related Literature ……………………………….…….…………… 6
CHAPTER 2: Terms and Definitions …………………………………………………………………. 12
CHAPTER 3: Factor Consideration in Choosing the Site …..…………….…………..…… 20
CHAPTER 4: Site Description ……………………………………………………………..…………..... 25
Manalo, April Gray Calderon, Leonard Andre’ _______________________________ ______________________________
Mortalla, Anjo Peguit, Jan Anthony
Microwave Link Design
ECEG11A – EC
APPROVAL SHEET
This is to certify that the group have designed, conducted studies and
documented important parameters in this microwave design which was prepared by the
group entitled MICROWAVE LINK SYSTEM DESIGN, and that this document has been
submitted for final examination by the oral examination committee.
_____________________________ ____________________________ Manalo, April Gray Calderon, Leonard Andre’ ____________________________ ____________________________ Mortalla, Anjo Peguit, Jan Anthony As member of the oral examination committee, we certify that we have
examined this document and hereby recommend that it be accepted as fulfillment for
the subject COMMUNICATIONS THEORY 5.
______________________________
Panel
This document is hereby approved and accepted by the Electronics Engineering
Department as fulfillment of the design requirement for the subject COMMUNICATIONS
THEORY 5.
______________________________ Engr. Antipas Teologo Jr.
Microwave Link Design
ECEG11A – EC
ACKNOWLEDGEMENT
We give our warmest thanks to the Calderon and Peguit family, for welcoming us
in their humble homes during those sleepless nights of labor and hardwork.
We also give our deep gratitude to Engr. Antipas Teologo Jr. who gave us the
opportunity to gain the knowledge we need through practical applications and designs.
We would also like to thank our parents who have supported us emotionally and
financially in making this design. And also for letting us go through with the series of
overnights to make this project successful. Your trust and understanding has given us
the energy and lessen the pressures that we have.
To the group, this would not be done without the trust and the cooperation
within our group. And this whole thing would not be possible if we never believed with
the capability of each other in doing our best.
And most especially, we give our thanks to the Lord Almighty for all the guidance
that He granted us in times of need. He unselfishly gave us wisdom to carry on and
finish this project. And we owe Him the strength that pushed us to continue in all that
we aim as a group, a friend and a family.
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To our PARENTS, FRIENDS, LOVED ONES and THE LORD ALMIGHTY…
Microwave Link Design
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Microwave Link Design
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CHAPTER 1
A. Objectives
B. Foreword to the Design
C. Scopes and Limitations
D. Significance of the Study
E. Review of Related Literature
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OBJECTIVES
• To be able to design a reliable Point-to-Point Microwave Cellular
Communications System
• To be able to design a “fully-operational” microwave link system having the ideal
reliability of 99.9999%
• To be able to know the general principles in Microwave Communications
• To be able to come up with a project that will help the students grasp the idea of
microwave design more comprehensively
• To be able to provide the students a material that will serve as their guide in
making their own microwave design
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FOREWORD
This paper describes and provides guidelines for the design and implementation
of a two-hop microwave communications system in Nueva Ecija, Philippines. Adherence
to these guidelines should allow significant terrain and propagation dynamics as well as
cost savings to be made for the pursuit of a highly reliable system. The suggested
procedure and considerations are presented with the fundamental components of
microwave path design: determining whether a proposed path is "line-of-sight",
evaluating path clearances with regard to refractive effects, evaluating path clearances
with regard to Fresnel zones, considering path reflections, deriving a power budget and
the fade margin as well as the path reliability.
This design focuses on a Microwave System designed for cellular communication.
The system link’s Site A is located on General Tinio, Site B is located on Tampak-I, and
Site C is located on Bongabon. A 13 Ghz operating frequency is used for both Hop 1 and
Hop 2 and in each relay station in an SFN (single frequency network), the coupling from
the transmitting antenna to receiving antenna causes loop interference. The
interference must be reduced to an allowable level in order to avoid problems with
distortion and oscillation so a Coupling Loop Interference Canceller was used.
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SCOPES AND LIMITATIONS
This part deals with the scopes and limitations of the design. These categorize
the reach and restrictions of the microwave system which might be useful to the
readers of the paper and on the people of Nueva Ecija.
The scope of the proposed project is focused on:
• The system is comprised of one transmitter, one receiver and one
repeater.
• The designed microwave link system is to operate at a frequency of
13Ghz for both Hop 1 and Hop 2.
• A circuit called Coupling Loop Interference Canceller is used in the system
to avoid co-channel interference in the transmit-receive process
The limitations of the proposed projects are as follows:
• The distance between sites of each hop is limited to 40 kilometers.
• The system is comprised of only two hops.
• The designed system is only to be used for cellular communication
purposes.
• The microwave link covers the province of Nueva Ecija only.
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SIGNIFICANCE OF THE STUDY
Prior to the advent of commercial wireless communications market today, most
microwave designs were destined for profitable applications. Because of the fast
phasing of technology, there is a need, for students who are not yet in the actual field of
their studies, to cope up with the technological advancements.
This design will be of great help to the students to practice everything they have
learned theoretically. This design intends to introduce the basics of microwave system
design to the students who are required to take up this subject as well as to those who
are interested in the field of microwave communications.
This design as well will serve as a reference for students who will take the
subject in the future.
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REVIEW OF RELATED LITERATURE
This part aims to briefly discuss the concepts of microwave communications
system, the design considerations and the components behind a fully functional system
that would work under the conditions of being a microwave communications system
design.
From researches about Microwave Systems, it specifies that there are so many
factors to consider in designing an effective and efficient microwave system.
Urgent Communications, Official Publication of IWCE
Microwave communications path design poses many
challenges. In addition to static gain and loss considerations,
terrain and propagation dynamics can play a large role in
determining whether a proposed path will have the required
signal levels, clearances and reliability.
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Electronic Communications Systems 5th
Edition, Tomasi, 2004, p.1021
The free-space path is the line-of-sight path directly
between the transmit and receive antennas (this is also called
the direct wave).
If a prospective path is not line-of-sight, then an alternate route is considered.
The transmit and receive antennas in a microwave system should have a line-of-sight to
be able to transmit the intended signal and data.
Determining whether a path is line-of-sight can be partially accomplished with
the aid of a topographical map. This type of map will show the various elevations along
the length of the path between proposed endpoints. Plotting these elevations at
intervals will produce a path profile showing terrain relative to the antenna elevations.
This graphical representation aids in determining not only whether a line-of-site
condition exists between endpoints but also in measuring clearances between the
center of the path and the surrounding terrain.
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When evaluating a proposed path, the path profile should be developed first.
This will identify path obstructions from terrain features. A field survey should follow,
which offers the necessary visual confirmation that the height of man-made
objects (which are not indicated on a topographical map) will not be located in or too
near the proposed path.
Communication Infrastructure Corporation, 2008
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Figure 1: K factors describe the effective Earth radius, e.g., the radius of a hypothetical
Earth for which the distance to the radio horizon in straight-line propagation is the same
as for the actual Earth with a uniform vertical gradient of atmospheric refractive index.
Less obvious barriers to microwave signals include the Earth’s curvature (k-
factor) and atmospheric conditions, which differ over geographic areas and change
locally throughout the year. In coastal areas, for example, changes in atmospheric
density due to temperature inversions, rain storms, and normal diurnal fluctuations can
vary the Earth’s effective curvature from 4/3 to 0.5. During the year, a typical
microwave path might experience a change in clearance by 20 feet or more. As
atmospheric fluctuations cause the beam to bend, the signal strength can easily vary by
20 to 30 dBm. (See Figure 2) In order to account for these fluctuations, the engineer
must carefully calculate the Fresnel zone clearance based on the likely range of k-factors
for the region where the microwave path is to be built. Thus, Fresnel zone clearance
cannot be determined through a visual LOS survey.
The entire path survey for a microwave link system includes four details
according to a microwave communications company and these are as follows:
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Communication Infrastructure Corporation, 2008
Detailed microwave path surveys include:
• Accurately locating the tower sites.
• Plotting the tower sites and deriving an elevation profile.
• Traversing the path on the ground to identify potential obstacles.
• Determining the antenna heights and performing a reflection
analysis.
Microwave link design covers a very wide range and field of study. A well-
planned system is very much required to reach the objectives in putting up a point-to-
point LOS link.
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CHAPTER 2
Terms and Definitions
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TERMS AND DEFINITIONS
Adjacent-channel interference fade margin (AIFM) (in decibels). Accounts for receiver
threshold degradation due to interference from adjacent channel transmitters.
Antenna bandwidth. The frequency range within which the antenna performance
meet specifications.
Antenna gain. A measure of directivity properties and the efficiency of the antenna. It
is defined as the ratio of the radiation intensity in the peak intensity direction to the
intensity that would be obtained if the power accepted by the antenna were radiated
isotropically. The difference between the antenna gain and the directivity is that the
antenna efficiency is taken into account in the former parameter. Antenna gain is
measured in dBi, i.e. decibels relative to isotropic antenna.
Branching losses. Comes from the hardware used to deliver the transmitter/receiver
output to/from the antenna.
Fading. Defined as the variation of the strength of a received radio carrier signal due to
atmospheric changes and/or ground and water reflections in the propagation path.
Four fading types are considered while planning links. They are all dependent on path
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length and are estimated as the probability of exceeding a given (calculated) fade
margin
Fading Margin. Number of decibels of attenuation which may be added to a specified
radio-frequency propagation path before the signal-to-noise ratio of a specified channel
falls below a specified minimum in order to avoid fading. Allowance made in radio
system planning to accommodate estimated fading.
First Fresnel Zone. Circular portion of a wavefront transverse to the line between an
emitter and a more distant point, where the resultant disturbance is being observed,
whose center is the intersection of the front with the direct ray, and whose radius is
such that the shortest path from the emitter through the periphery to the receiving
point is one-half wavelength longer than the direct ray.
Flat fade margin. In an analog microwave radio system, the flat fade margin is equal to
the system total Gains minus system total losses. In a digital microwave radio system,
the "flat" or thermal fade margin (TFM) is calculated from the system total Gains minus
system total losses.
Free Space Loss. The signal attenuation that would result if all absorbing, diffracting,
obstructing, refracting, scattering, and reflecting influences were sufficiently removed
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so as to have no effect on propagation. Note: Free-space loss is primarily caused
by beam divergence, i.e., signal energy spreading over larger areas at increased
distances from the source.
Fresnel Zone. Circular portions of a wavefront transverse to a line between an emitter
and a point where the disturbance is being observed; the nth zone includes all paths
whose lengths are between n -1 and n half-wavelengths longer than the line-of-sight
path. Also known as half-period zones.
Figure 2: Fresnel Zone in relation to distance
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Gas absorption. Primarily due to the water vapor and oxygen in the atmosphere in the
radio relay region.The absorption peaks are located around 23GHz for water molecules
and 50 to 70 GHz for oxygen molecules.The specific attenuation (dB/Km)is strongly
dependent on frequency, temperature and the absolute or relative humidity of the
atmosphere.
Interference fade margin (IFM). Is the depth of fade to the point at which RF
interference degrades the BER to 1x 10-3 . The actual IFM value used in a path
calculation depends on the method of frequency coordination being used.
Line of Sight. An unobstructed view from transmitter to receiver.
Link Budget. The accounting of all of the gains and losses from the transmitter, through
the medium (free space, cable, waveguide, fiber, etc.) to the receiver in
a telecommunication system. It accounts for the attenuation of the transmitted signal
due to propagation, as well as the antenna gains, feed line and miscellaneous losses.
Randomly varying channel gains such as fading are taken into account by adding some
margin depending on the anticipated severity of its effects
Microwave. These are the ultra high, super high and extremely high frequencies
directly above the lower frequency ranges.
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Microwave Link Design. A methodical, systematic and sometimes lengthy process that
includes
• Loss/attenuation Calculations
• Fading and fade margins calculations
• Frequency planning and interference calculations
• Quality and availability calculations
Miscellaneous (other) losses. Unpredictable and sporadic in character like fog, moving
objects crossing the path, poor equipment installation and less than perfect antenna
alignment etc.
Multipath Fading. The dominant fading mechanism for frequencies lower than 10GHz.
A reflected wave causes a multipath, i.e.when a reflected wave reaches the receiver as
the direct wave that travels in a straight line from the transmitter.
Multipath Interference. When signals arrive at a remote antenna after being reflected
off the ground or refracted back to earth from the sky (sometimes called ducting), they
will subtract (or add) to the main signal and cause the received signal to be weaker (or
stronger) throughout the day.
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Parabolic Antenna can be used as a transmit and receive antenna with both Single and
Dual polarized feeds available. Frequencies from 1.7 to 23.6 GHz can be accommodated
just by changing out the Feed assembly. Various mounting hardware and accessories
availably. Dual frequency and specialty feeds are also available.
Propagation losses. Losses due to Earth’s atmosphere and terrain.
Rain Attenuation. Attenuation of radio waves when passing through moisture-bearing
cloud formations or areas in which rain is falling; increases with the density of the
moisture in the transmission path.
Receive Signal Level. Receive signal level is the actual received signal level (usually
measured in negative dBm) presented to the antenna port of a radio receiver from a
remote transmitter.
Receiver Sensitivity. Receiver sensitivity is the weakest RF signal level (usually
measured in negative dBm) that a radio needs receive in order to demodulate and
decode a packet of data without errors.
Receiver sensitivity threshold. Is the signal level at which the radio runs continuous
errors at a specified bit rate
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Refraction – Diffraction Fading. Also known as k-type fading. For low k values, the
Earth’s surface becomes curved and terrain irregularities, man-made structures and
other objects may intercept the Fresnel Zone. For high k values, the Earth’s surface gets
close to a plane surface and better LOS(lower antenna height) is obtained. The
probability of refraction-diffraction fading is therefore indirectly connected to
obstruction attenuation for a given value of Earth –radius factor.
System Operating Margin. System operating margin (SOM) is the difference (measured
in dB) between the nominal signal level received at one end of a radio link and the signal
level required by that radio to assure that a packet of data is decoded without error.
Thermal fade margin (TFM). In db, is the difference between the normal received
signal RSL at the input of microwave receiver expressed in dbm and the receiver's
threshold ( given by the manufacturer) expressed in dbm (TFM = RSL - TH )
Transmit Power. The transmit power is the RF power coming out of the antenna port of
a transmitter. It is measured in dBm, Watts or milliWatts and does not include the signal
loss of the coax cable or the gain of the antenna.
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CHAPTER 3
Factor Consideration in Choosing the Site
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FACTOR CONSIDERATION IN CHOOSING THE SITE
For many wireless carriers, microwave is becoming a popular choice over wire
line transport. It is an attractive option for many reasons, especially as radio equipment
costs decrease. Low monthly operating costs can undercut those of typical expenses,
proving it more economical over the long term. But before you move forward, make
sure you understand all of the design considerations that will affect your deployment.
First, it is important to understand the relationship between capacity, frequency
band, path distance, tower heights, radio equipment and antennas.
Frequency Options
Wavelengths in the lower frequencies are longer, which is important because the
wavelength determines how the atmosphere affects transmission. The atmosphere may
refract longer waves. Refraction can reduce the length of the path, or microwave hop.
Microwave Systems in the 2GHz to 6GHz frequencies can transmit over longer
distances, which make them more suitable for rural areas. High-frequency systems are a
better fit for suburban and urban environments.
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Terrain and Weather
Because line of sight is a microwave requirement, terrain such as mountains,
hills, trees and buildings can block a microwave signal and limit the distance of a
microwave path.
Capacity is another important consideration. You can configure radios to carry a
certain amount of traffic in a specific frequency. Based on capacity and radio
equipment, antenna size, tower heights and terrain elevation will play a major role in
how you plan and construct the system. These four factors also will dictate system
reliability, multi-path fading, fade margin calculations, fresnel zone clearance,
interference analysis, system diversity and long-distance specifications.
You will use a large antenna (low frequency) when the path is longer. Large
antennas require large towers and have higher wind factors. As a result, you also must
consider existing tower loads to ensure that you can implement the design on existing
or planned towers and structures.
You also must take into account attenuation, the reduction in energy as a signal
travels through equipment, transmission lines or air. The term often refers to the impact
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of rain, or fog as well as normal signal loss in the waveguide and microwave system
itself.
Path reliability normally has to meet the same standards as the rest of the
microwave system. Reliability objectives are often stated on a per hop basis or end-to-
end. The objective applied to each hop is limited to a distance of 35km to 40km, having
a ratio of 2cm : 1km.
Fading mechanisms considered include fading due to multipath phenomena,
obstructions, and rain attenuation. Equipment and power-source reliability demands are
dealt with through a combination of highly reliable components plus designs that
incorporate redundancy and protection.
Equipment Selection
When selecting equipment, determine the amount of power the system uses to
transmit and receive signals. More power usage equates to higher operating costs.
System planners should perform path calculations to establish fade margins and system
gain, taking into account an estimate of system downtime for the locale of the planned
radio (average rainfall). Fade margin is the allowance made to accommodate estimated
propagation fading without exceeding a specified signal-to-noise ratio.
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With careful attention to link gain power, antenna height, receiver sensitivity,
free space loss, attenuation and availability requirements, you can integrate microwave
radio effectively into virtually any wireless system.
Population
Sites A, B, and C are located at towns in Nueva Ecija where the population is not
that large, to avoid so much of external interference, however, the population is not
that small as well to attain the objective of providing reliable information signals to the
people.
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CHAPTER 4
Site Description
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SITE DESCRIPTION
Province of Nueva Ecija, Philippines
Founded in 1705 by Spanish Governor
General Don Fausto Couzar, he named the province
after his homeland Ecija in Seville, south of Spain.
The province has three cities: Cabanatuan, San Jose, and Palayan, its capital.
Nueva Ecija has a total land area of 550,718 hectares with 29 municipalities consisting
of: Aliaga, Bongabon, Cabiao, Carranglan, Cuyapo, Gabaldon, Gapan, General M.
• Saint John District (Pob.) • San Agustin • San Andres • San Bernardino • San Marcelino • San Miguel • San Rafael • San Roque • Santa Ana • Santa Cruz • Santa Lucia • Santa Veronica District
(Pob.) • Santo Cristo District
(Pob.) • Saranay District (Pob.) • Sinulatan • Subol
Path Length (Site A – Site B): 40 km Path Length (Site B – Site C): 40 km Reliability Requirement: 99.9995% - 99.9999%
B. TOPOGRAPHICAL SITE OF THE MAP
The Scale used is 1:50,000 Hop 1: Sampaguita, General Tinio, Nueva Ecija to Tampac I, Guimba, Nueva Ecija Hop 2: Tampac I, Guimba, Nueva Ecija to Larcon, Bongabon, Nueva Ecija
C. FREQUENCY PLAN
For Hop 1: Frequency Band: 13 GHz Frequency Range: 12.75 – 13.25GHz For Hop 2: Frequency Band: 13 GHz Frequency Range: 12.75 – 13.25GHz
D. FREE SPACE LOSS
FSL = 92.4 + 20 log (fGHz) (D)
For Hop 1 & Hop 2 LBF: FSL = 92.4 + 20 log (12.75) (40) = 146.55 dB HBF: FSL = 92.4 + 20 log (13.25) (40) = 146.86 dB
Do = 2.35 DE = D/ [1 + (D/Do)] Hop 1: DE = 40 / [1 + (40/2.35)] = 2.22
Hop 2: DE = 40 / [1 + (40/2.35)] = 2.22
J. RAIN ATTENUATION
Hop 1 & Hop 2 LBF:
γ = k (180)α
γ = 0.029 (180)1.17
γ = 12.62
Arain = DE (γ) Arain = 2.22 (12.62) Arain = 28.0164 dB
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HBF:
γ = k (180)α
γ = 0.025 (180)1.18
γ = 11.46 Arain = DE (γ) Arain = 2.22 (11.46) Arain = 25.4412 dB
K. ATMOSPHERIC LOSSES
o Oxygen Absorption Loss
Ao = [7.19 x 10-3 + (6.09/(f2 + 0.227)) + (4.81/((f-57)2 + 1.5)))] (f2 x 10-3) D
LBF: Ao = [7.19 x 10-3 + (6.09/(12.752 + 0.227)) + (4.81/((12.75 – 57)2 + 1.5)))] (12.752 x 10-3) D Ao = 7.79 x 10-3 dB/km Ao for 40 km = 0.3116 dB HBF: Ao = [7.19 x 10-3 + (6.09/(13.252 + 0.227)) + (4.81/((13.25– 57)2 + 1.5))] (13.252 x 10-3) D Ao = 7.78 x 10-3 dB/km Ao for 40 km = 0.3112 dB
Hop 1 LBF: U = 1 x 10-9 (12.751.2)(403.5)(10(-28.08/10)) = 1.34 x 10-8
HBF: U = 1 x 10-9 (13.251.2)(40 3.5)(10(-28.57/10)) = 1.25 x 10-8
Hop 2 LBF: U = 1 x 10-9 (12.751.2)(403.5)(10(-23.48/10))
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= 3.85 x 10-8
HBF: U = 1 x 10-9 (13.251.2)(40 3.5)(10(-23.97/10)) = 3.60 x 10-8
R = (1 – U) x 100%
For Hop 1
LBF: R = (1 – 1.34 x 10-8) x 100% = 99.99999866%
HBF: R = (1 – 1.25 x 10-8) x 100% = 99.99999875%
For Hop 2
LBF: R = (1 – 3.85 x 10-8) x 100%
= 99.99999615%
HBF: R = (1 – 3.60 x 10-8) x 100% = 99.9999964%
P. K-Q RELIABILITY WITH TERRAIN ROUGHNESS
U = (K-Q/S1.3) x fb x Dc x 10(-FMeff/10)
Hop 1: LBF: U = (1 x 10-9/15.491.3) (12.751.2) (403.5) (10(-28.08/10)) = 3.79 x 10-7
HBF: U = (1 x 10-9/15.491.3) (13.251.2) (40 3.5) (10(-28.57/10)) = 3.55 x 10-7
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Hop 2:
LBF: U = (1 x 10-9/15.161.3) (12.751.2) (403.5) (10(-23.48/10)) = 1.12 x 10-6
HBF: U = (1 x 10-9/15.161.3) (13.251.2) (40 3.5) (10(-23.97/10)) = 1.05 x 10-6
R = (1 – U) x 100%
Hop 1: LBF: R = (1 – 3.79 x 10-7) x 100% = 99.9999621%
HBF: R = (1 – 3.55 x 10-7) x 100% = 99.9999645%
Hop 2: LBF: R = (1 – 1.12 x 10-6) x 100% = 99.99988%
HBF: R = (1 – 1.05 x 10-6) x 100% = 99.999895%
Microwave Path Data Sheet
Customer: TELCO Project Number: 3 Frequency Band Used: 13 GHz Low Band Frequency: 12.75 Ghz High Band Frequency: 13.25 GHz Equipment: Digital Microwave Radio AT 9900 Site A: Sampaguita, General Tinio, Nueva Ecija Site B: Tampac I, Guimba, Nueva Ecija Site C: Larcon, Bongabon, Nueva Ecija Hop 1 Path Length: 40 km Hop 2 Path Length: 40 km
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Site Information Gen. Tinio (A) Guimba (B) Bongabon (C)
Longitude: 121’ 02’35.9” 120’ 47’19.8” 121’ 09’44” Latitude: 15’ 21’32.7” 15’ 37’20.6” 15’ 38’15.9” Site Elevation: 0 0 0 Antenna Height: 80 m 90 m 120 m Equipment Information
Transmitter Output Power: 26 dB Receiver Input Threshold: - 91 dB Connector Loss: 0.5 dB Waveguide Loss: Site A: 11.51 dB Site B: 12.66 dB Site C: 16.11 dB Antenna Gain – Low: 41.4 dB High: 41.8 dB
Path Losses LBF HBF
Free Space Loss: 146.55 dB 146.86 dB Atmospheric Loss: 0.3116 dB 0.3112 dB Water Vapor Loss: 0.0744 dB 0.0836 dB Rain Attenuation: 28.0164 dB 25.4412 dB Fade Margins Hop 1 Hop 2
LBF HBF LBF HBF Thermal FM: 28.08 dB 28.57 dB 23.48 dB 23.97 dB Flat FM: 25.07 dB 25.56 dB 20.46 dB 20.96 dB Effective FM: 28.08 dB 28.57 dB 23.48 dB 23.97 dB
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Path Reliability LBF HBF
: K-Q Reliability Calculation: Hop 1: 99.99999866% 99.99999875% Hop 2: 99.99999615% 99.9999964% K-Q Reliability Calculation w/ Terrain Roughness Hop 1: 99.9999621% 99.99988% Hop 2: 99.9999645% 99.999895%
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CHAPTER 7
Conclusion and Recommendation
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CONCLUSION AND RECOMMENDATION
Microwave link design is a specific sort of engineering in the broader field of
communications. Most installers know that clear line of sight is required between two
antennas, but there is a lot more to it than that. To have some certainty as to whether
your wireless link will be reliable, an RF path analysis needs to be performed.
A clear understanding of the microwave network build-out process is essential
for the successful implementation of a project, whether it is a new system or an
upgrade/expansion of an existing one.
Upon the completion of this design, we were able to meet the needed outcomes
and conditions regarding the design. We were able to make a Point – to –Point Cellular
Link System design having a 99.99999% reliability.
Due to the importance of a design like this, we highly recommend this paper to
the students who are interested in microwave communications system design and to
those who are required to take the subject Microwave Engineering and make their own
link design.
Microwave Link Design
ECEG11A – EC
CHAPTER 8
Equipment Specifications
Microwave Link Design
ECEG11A – EC
Bibliography
Books:
Ampoloquio, J. (2005), SUPERBook Electronic Systems and Technology
Blake, R. (2008), Electronic Communication Systems – 2nd
Edition, Singapore: Delmar
Freeman, R. (1991), Telecommunications Transmission Handbook – 3rd
Edition, Canada:
Wiley & Sons
Frenzel, L. (1994), Communications Electronics – 2nd
Edition, Singapore: Mcgraw-Hill
Rule, M,. Fundamentals of Microwave Communication with Microwave Planning Guide
Tomasi, W. (2004), Electronic Communications System – 5th