Survey System Design and Engg

SURVEY, SYSTEM DESIGN, ENGINEERING FOR LINE OF SIGHT LINKS AND GUIDELINES FOR SURVEYCONTENTS1.Transmission Concepts.2.Parameters for path loss calculations3.Survey of LOS links:Preliminary surveyMap studiesDetailed surveyFeasibility study and report generationGuidelines for LOS SurveyTransmission Planning Guidelines-Nokia for Bharti Cellular Limited

LINE OF SIGHT LINKS (LOS)AIMS OF THE COURSETO ENABLE YOU TO PLAN LINE OF SIGHT POINT TO POINT MICROWAVE LINKS AND PERDICT THE PERFORMANCEOF THE LINK YOU HAVE PLANNED.STUDY OF SURVEY OF INDIA MAPS, MARKING OF SITES, ESTABLISHING OF HOP AND LOCATION OF CRITICAL POINTS.CARRY OUT SURVEY, WHICH IS MOST IMPORTANT PART OF LINK DESIGNING TO FIND OUT WHAT IS GOING TO BE THE TOWER HEIGHTS BETWEEN ANY TWO POINTS OF A HOP.

LINE OF SIGHT LINKS (LOS)(PURPOSE AND REQUIREMENT)PurposeFor the establishment of short / long haul LOS linksFeasibility studiesSubmission of tendersUp gradation of existing linksRequirements of LOS linksSignals follow straight linesSignals are affected by free space attenuation and precipitationUse of frequencies greater than 150 MHzUse of spread spectrum and time sharing techniques

TRANSMISSION CONCEPTSA simplified transmission system:TransmitterReceiverTransmission Media

TRANSMISSION CONCEPTSTypes of Media:Open wire copper cable systemCoaxial cable systemsHigh frequency radio communication systemsLine of sight communication systemsTroposphere scatter systemsSatellite communication systemsOptical fiber cable systems

TRANSMISSION CONCEPTSTransmission Concepts:Decibel (dB):- The decibel is a unit that describes a ratio.Number of decibels (dB)=10 log10 P2/P1, P1 is lower and P2 is higher power.

dBm:- Is a power level related to 1 m W power (0 dBm=1 mW)Power (dBm) = 10 log power (mW)/1 mWIf power of an amplifier is 20 W, Whats it output in dBm?Power dBm = 10 log 20x103 mW/1 mW = + 43 dBm(Plus sign indicates that the quantity is above reference of 0 dBm)If input to a network is 0.0004 W, Whats the input in dBm?Power dBm = 10 log 4 x 10-1 mW/1 mW = - 4 dBm(minus sign indicates that the quantity is below reference of 0 dBm)NetworkP1P2If P1=1W P2=2WGain dB=10 log 2/1 =3 dBP1=1000WP2=1WLoss dB=10 log 1000/1 =30 dB

TRANSMISSION CONCEPTSdBW:- is extensively used in microwave applications. It is an absolute decibel unit referred to 1W.Power level (dBW) = 10 log power (W) /1 W (+30 dBm=0 dBW)dBmV:- is extensively used in video transmission. It is voltage level in decibels above and below 1 mV across 75 .Voltage level dBmV=20 log mV/1 mV10 V = + 80 dBmV 1V = + 60 dBmV1mV = 01V = -60 dBmV

TRANSMISSION CONCEPTSSignal-to-Noise Ratio: The signal-to-noise ratio expressed in decibels (dB) is the amount by which a signal level exceeds its corresponding noise.

S/N dB = Signal Level dBm Noise Level dBmNoise Figure: All networks active or passive contribute noise to a transmission system. The noise figure is a measure produced by a practical network compared to an ideal network i.e. one that is noise less. For a linear system noise figure is expressed by:-NF (dB) = 10 log 10 Signal-to-Noise in / Signal-to Noise out0203060NoiseSignalFrequency

TRANSMISSION CONCEPTSEffective Isotropic ally Radiated Power (EIRP): This is an antenna performance expressed in dBm or dBW over an isotropic antenna, which radiates energy uniformly in all directions and has a gain of 1 or 0 dB and is an imaginary antenna used as a reference.High Frequency Radio (HF): Radio frequency transmission between 3 and 30 MHz is called HF. HF propagation is characterized by ground waves and sky wave component.Ground waves follow surface of the earth and can provide useful communication up to about 650 Km.Sky waves permits reliable communication (up to 90 % path reliability) for distances of 6500 Km and even more. The ionosphere is the key to HF sky wave communication*.

TRANSMISSION CONCEPTSTerminal, Repeater (R/R), Drop Insert, Hop and Link concept for LOS links:Terminal-ATerminal-B

Drop Insert-4Drop Insert-8R/R-1R/R-2R/R-3R/R-5R/R-6R/R-7R/R-9Hop-7Hop-1Hop-2Hop-3Hop-4Hop-5Hop-6Hop-8Hop-10Microwave Vs OFC Route130 Km139 Km65 KmHop-9

LINE OF SIGHT LINKS (LOS)(LINK ENGINEERING)Selection of sites which are in line-of-sight of each otherSelection of an operational frequencyDevelopment of path profiles to determine economic tower heightsPath calculations so as to achieveDesired reliability for given fade margin and threshold levelMaking path survey to ensure correctness of steps 1-4Equipment configuration to achieve fade marginsEstablishment of frequency planFinalization of bill of quantitiesPlacement of orders for equipments & towersInstallation testing and commissioning of links

LINE OF SIGHT LINKS (LOS)(LINK ENGINEERING)GENERAL FREQUENCY ASSIGNMENTS (BANDS)FREQUENCY WAVE LENGTH (CM)LF : 30 kHz-300 kHzMF : 300 kHz-3 MHz HF : 3 MHZ-30 MHzVHF : 30 MHZ-300 MHzUHF : 300 MHz-3GHzSHF : 3 GHz-30 GHz100mm-10mmEHF : 30 GHz-300 GHZTHESE BANDS ARE FURTHER DIVIDED INTO SUB-BANDS

PARAMETERS FOR PATH LOSS CALCULATIONS(Limitations of Line of Sight Systems)How far we can go: The range of LOS microwave systems is limited by:-Curvature of earth-ActualTechnical radio characteristics (K-factor)-Modified Earth CurvatureActual Obstructions en-route in each hopRF effect of fresnel zonePath lossTransmitter powerAntenna gainsTransmission line loosesFrequency of operationReceived powerReceiver thresholdSignal to noise ratioFade margin requiredDesired reliability of link

PARAMETERS FOR PATH LOSS CALCULATIONS(Design of Line of Sight Microwave Links)Link Design: The design of microwave links, involves three sets of calculations.Working out antenna heights for the link.K-factor is major dominant variable.Earth bulge.Fresnel zone radius.Actual obstructions on the routePath LossOperating frequency.Path profile: it indicates the distance from one of the transmitter site where obstructions to the line of sight radio link may occur.The object of this calculation is to arrange tower heights along the entire route of the link, so that an obstruction in the path does not enter into the fresnel zone by a specified amount for a specified K-factor used.

PARAMETERS FOR PATH LOSS CALCULATIONS(Design of Line of Sight Microwave Links)To determine equipment and other parameters for each hop.Transmit power.Antenna type and gain.Transmission type.Other losses. (Absorption, Diffraction, Reflection or Scattering etc.)Maximum received power.Receiver threshold.This will decide the thermal fade margin, which we will be able to get for each hop.To determine the reliability of each hop and overall reliability of the link.Climatic factor.Terrain roughness.Average annual temperatureAnnual rain.This will decide, what is total expected outage time per annum for each hop as well as for the entire link.

PARAMETERS FOR PATH LOSS CALCULATIONS(Free Space Loss)PROPAGATION:Free space loss: consider a signal is traveling between transmitter at A to a receiver at B. There is for a given frequency and distance, a characteristic loss. This loss increases with both distance and frequency. It is known as free space loss.

Free space loss LdB=92.44+20 log10 F+20 log10 DWhere F is in GHz and D is in km's.If D is 40 Km and F is 6 GHz, then free space in dBLdB=92.44+20 log 40+20 log 6 =92.44+20*1.6021+20*0.7782 =92.44+32.042+15.564=140.046 dB (

PARAMETERS FOR PATH LOSS CALCULATIONS(Free Space Loss)Free space loss:Example:- Free space loss if F=2.5 GHz and D=30 KmFSL (dB) = 92.44 + 20 log 2.5 + 20 log 30=92.44 + 20*0.398 + 20*1.478 =92.44 + 7.96 + 29.56 = 129.96 dBNow, if F=7.5 GHz (changed) and D=30 Km (unchanged)FSL (dB) = 92.44 + 20 log 7.5 + 20 log 30 =92.44 + 20*0.875 + 20*1.478 =92.44 + 17.5 + 29.56 = 139.5 dBNow, if F=2.5 GHz (unchanged) and D=40 Km (changed)FSL (dB) = 92.44 + 20 log 2.5 + 20 log 40=92.44 + 20*0.398 + 20*1.602=92.44 + 7.96 + 32.04 = 132.44 dBIt can be seen, that, free space loss increases both with distance and frequency

PARAMETERS FOR PATH LOSS CALCULATIONS (Fictitious Earth Curvature)Earth bulge and K-factor:The propagation of radio beam is affected by atmospheric conditions and the obstructions on the way. It can be subjected to:DiffractionReflectionRefractionMost important is refraction, which is caused by changes in the density of atmospheric layers confronted by the radio beam front. The curvature of earth and slight bending of waves as it is refracted downwards by the earths atmosphere are two factors, that, must be considered while making path profiles.The earths curvature and microwave beam refraction are combined to form fictitious earth curvature or earth bulge.EARTH CURVATURE (M)=0.078 x d1 x d2 / KWHERE K= EFFECTIVE EARTH RADIUS/TRUE EARTH RADIUSEARTH BULGE=d1 x d2 / 12.75 x KEARTH BULGE FOR K=4/3=d1 x d2 / 17EARTH BULGE FOR K=2/3=d1 x d2 / 8.5

PARAMETERS FOR PATH LOSS CALCULATIONS ( TOWER HEIGHT FOR DIFFERENT VALUES OF K)

PARAMETERS FOR PATH LOSS CALCULATIONS (EARTH BULGE FOR VARIOUS K- FACTORS)hdDEPARTURE FROM A LEVEL TANGENT, hDISTANCE FROM CENTER OF PATH dh=2d2/3KK=4/3K=1K=2/3K=5/12K=1/2K=7/615 10.58112225h is in feet and d is in miles

PARAMETERS FOR PATH LOSS CALCULATIONS(Fresnel Zone)Fresnel zone:The radio beam energy travels in an ellipsoidal wave front, the different components of which maintains different path lengths.The distance from microwave beams center is commonly measured in fresnel zones to take into account both frequency and distance.The first fresnel zone (FFZ) is the surface of the point along which the distance to the ends of the path is exactly wave length larger than the direct end to end path.FFZ radius in meters=17.32d1*d2/fDWhere d1 & d2 are in kms, f is the frequency in GHz and D is the hop distance in Kms.In order to achieve a free space propagation condition for a radio beam at least 60 % of FFZ should be cleared under the standard atmospheric condition of K=4/3.

PARAMETERS FOR PATH LOSS CALCULATIONS(Fresnel Zone)FFZ radius in meters=17.32d1*d2/fD, If f=2.5 GHz and D=30 Km, then FFZ=32.99 MIf f=4.5 GHz and D=30 Km, then FFZ=24.03 MIf f=6.5 GHz and D=30 Km, then FFZ=19.75 MIf f=7.5 GHz and D=30 Km, then FFZ=17.32 MIf f=18.5 GHz and D=30 Km, then FFZ=11.43 MFFZ radius decreases with increase in frequency.If f=2.5 GHz and D=30 Km, then FFZ=32.99 MIf f=2.5 GHz and D=34 Km, then FFZ=35.33 MIf f=2.5 GHz and D=36 Km, then FFZ=36.46 MIf f=2.5 GHz and D=40 Km, then FFZ=38.64 MIf f=2.5 GHz and D=50 Km, then FFZ=43.73 MFFZ radius increases with increase in distance.

PARAMETERS FOR PATH LOSS CALCULATIONS(KNIFE-EDGE LOSS CALCULATIONS)-1-0.500.51.01.52.02.5-40-30-20-100+10FRESNEL ZONE NUMBERS123456R=1.0R=0.3R=0dBOBSTRUCTION ZONEINTERFERENCE ZONER= REFLECTION COEFFICIENT CLEARANCE / FIRST FRESNEL ZONER=1.0R=0

PARAMETERS FOR PATH LOSS CALCULATIONS(FIRST FRESNEL ZONE AND EARTH BULGE)NATURAL EARTH FEATURESEARTH BULGEFIRST FRESNEL ZONE RADIUSABTBUILDINGd1d2Df

PARAMETERS FOR PATH LOSS CALCULATIONS(PROPAGATION CONDITIONS)

PARAMETERS FOR PATH LOSS CALCULATIONS (REFLECTION POINT) The reflection point area lies between a k-factor of grazing (k=1) and a k-factor of infinity.From the profiles, possible reflection points can be obtained.The object is to adjust tower heights, such that, the reflection point is adjusted to fall on land area, where the reflected energy is broken up and scattered (forest/wooded area).Water bodies and other smooth surfaces cause reflection, which is undesirable.Figure will assist in adjusting the reflection point.It uses a ratio of tower heights h1/h2, where shorter tower is always h1 and distance expressed is always from h1.By adjusting the ratio h1/h2 the reflection point can be moved.For a highly reflective path, we may go in for space diversity.

PARAMETERS FOR PATH LOSS CALCULATIONS(REFLECTION POINT) 0.10.20.30.40.50.60.70.80.91.01.00.10.20.30.40.5Ratio of Tower Heights h1 / h2d1 / DDistance to Reflection Point/Total DistanceK of GrazingK of Infinity

PARAMETERS FOR PATH LOSS CALCULATIONS(DIVERSITY OPERATION)Diversity Operations is based on the fact, that, radio signals received over different paths will have different levels i.e. if one is faded, other may not. The separation may be in:FrequencySpace (Including angle of arrival and polarization)Polarization Diversity (Fade may not be same on both polarizations)Angle Diversity ( Split energy at feed horn and signals arrive on separate paths)Most common are Frequency (separated by 2-3 %) and Space (separated by 100-200 , so that the reflected wave travels wave length further than the normal path). The space diversity improvement can be calculated by Vagrant's formula applied to fading margins. The improvement factor on fading margin is:Le=10 log (1.2 x10-3 x S2 x V2 x fm/d), where:S= Separation between the antennasV= Power ratio between the two receiversf = Frequency in GHzm= Selective margin (Number)d= Hop distance in KmsImprovement is limited to 200.Greater improvement can be obtained by combining frequency and space diversity.

PARAMETERS FOR PATH LOSS CALCULATIONS(RECEIVER SENSITIVITY, FADE MARGIN AND SIGNAL TO NOISE RATIO)Receiver Sensitivity: Sensitivity or Threshold Power of receiver is the level of signal which would produce a 30 dB signal to noise ratio out of the base band of an analogue receiver, or a bit error ratio (BER)=10-4 out of the base band of a digital receiver. Typically it is -70 to -90 dB.Fading: Received Signal vary with time due to multipath fading and rain etc. Refractive index of atmosphere varies with Temp. humidity and pressure which in turn cause the electromagnetic waves to change direction. Another cause for Multipath fading is ground reflection. So a fade margin is built in Link Designing.Fade Margin: The fade margin is the power level, that, the unfaded received signal can fall to until it reaches the receiver threshold. This margin will vary depending on geographic and climatic conditions of different geographic areas and desired reliability of the system. Typically it is 20-40 dB.Fade Margin dB=Prx-Pthresh

Signal to Noise Ratio: Its the minimum power difference between the wanted received signal and received noise.Signal/Noise Ratio (dB)=10 log10 (Signal Power/Noise Power)Typically it is > 50 dB, logically it should be more than the Fade Margin, so that it is always below the threshold level.

PARAMETERS FOR PATH LOSS CALCULATIONS(System and Link Reliability)Reliability of the link: Outage time for each hop and for the complete link is to be worked out, which in turn will give the over all reliability of the link in terms of percentage. Rayleigh fading chart is given below.Single hop reliability (%)Fade Margin99.928 dB99.9938 dB99.99948 dBCCIR defines its availability objective for radio relay systems over a hypothetical reference circuit as 99.7 %. Resulting unavailability 0.3 % is of three components.Outage due to power failureOutage due to equipment failureOutage due to propagationIt is reasonable to allot 50 % of the outage time to power and equipment failures and 50 % for propagation. Considering propagation alone, system should have an availability (reliability) of 99.85 % apportioned across the 2500 Km route. This provide guide to establish a per hop propagation reliability for a particular system.Planner rather first set the limit for the reliability and for wide band links it is better than 99.99 %.

PARAMETERS FOR PATH LOSS CALCULATIONS(LOS LINK GAINS AND LOSSES SIMPLIFIED)ANTENNA GAINLINE LOSSESFREE SPACE LOSS=139.2 dBANTENNA GAINLINE LOSSES11 GHzEIRP= + 60.5 dBm27dBmLINE LOSS EACH=1.5 dBANTENNA GAIN EACH END=35 dB20 Km-68dBm-47.2 dBmRECEIVERINPUTdBMisc. Loss=2dB

PARAMETERS FOR PATH LOSS CALCULATIONS(LOS LINK GAINS AND LOSSES SIMPLIFIED)

PARAMETERS FOR PATH LOSS CALCULATIONS(DETAILED PATH LOSS CALCULATION SHEET)Site from:to:Link name:Equipment type:Frequency:Transmit power:Nominal received power:Receiver threshold:Desired fade margin:Desired reliability:Hot standby / frequency diversity and / or space diversity:Azimuth A B:Azimuth B A:Path length:Path length:

PARAMETERS FOR PATH LOSS CALCULATIONS(DETAILED PATH LOSS CALCULATION SHEET)

SURVEY OF LOS LINKS(PRELIMINARY SURVEY)Topography of an area is to be extensively studied with the help of detailed survey maps.Initial study of the given linkAerial/quick survey of terrain/map studySelection of media of communication LOS/OFC/Satellite etcFormulation of best route & an alternate routeSelection of tentative sites & repeatersMost techno economical media and route to be finalized

SURVEY OF LOS LINKS(PRELIMINARY SURVEY)Points to ponder for site selectionNear approach roads for accessibilityNear power supply lines to avoid solar powerSmall hillocks gives height advantage & reduced tower heightsAvoid lakes big water reservoirsDense forests fineStudy of other routes around the area

SURVEY OF LOS LINKS (MAP STUDIES)It will be found, that, a through map study will narrow down the problem considerably particularly in case of multi-repeater systems with a wide range of choices. By checking a number of possible routes from map data alone, it will be usually possible to reduce the choice down to a few alternativesSurvey maps are available for every country & now digitized in most of the countries2.Survey of India Topographical maps in different scales of (1:250,000, 1:50,000 and 1:25,000) provides most excusive information3.Indias co-ordinates areLongitude 68 to 96 degrees ELatitude 8 to 36 degrees NFor preliminary survey i:2,50,000 scale or larger scales to be studied where as for detailed survey 1:50,000 or 1:25,000 scales are requiredTentative sites to be marked on the mapsEach hop needs detailed study for working out exact tower heights

SURVEY OF LOS LINKS (MAP STUDIES-INDEX OF MAPS)8121620242832366872768084889296Longitude E of GreenwichLatitude N

SURVEY OF LOS LINKS (MAP STUDIES)Survey of India have divided India in to blocks and maps numbered. Each 1:250,000 sheet contains sixteen 1:50,000 sheets, which are numbered from 1-16 i.e. say number 84 is divided into 16 segments 84 A to 84 P as shown opposite. Each such map is in the scale of 1: 250,000.

SURVEY OF LOS LINKS (MAP STUDIES)Each segment is further divided in to 16 sections say 84 A/1 to 84 A/16, which are 1:50,000 scale. For 1:25,000 scale maps, each map is further divided into 4 viz 84 A/2 will have 84A/2/NW, 84A/2/NE,84A/2/SW and 84A/2/SE.Most likely sites will be located on different maps, which may have to be joined to study individual hops

SURVEY OF LOS LINKS (MAP STUDIES)PATH PROFILINGAfter tentative terminals or repeater sites are selected, draw a straight line on maps connecting two adjacent sitesCarefully trace from one site to another, marking all obstacles or obstructions and possible points of reflectionMark the mid point, which is point of maximum earth bulge and to be marked as obstaclePath profiles are plotted on rectangular graph paper or recorded for feeding in to computerHASL of all obstacles between two sites marked on the map are to be taken in to account at 1-2 km intervalCarefully mark water bodies viz lakes, rivers, ponds etc for evaluation of reflection points.Contour interval is at 5/10/20 M, bench mark heights can be located in the maps, heights of most of the hill tops is also given.Study of maps will give an idea, which of the critical points have to be visited and how to approach them during actual survey.

SURVEY OF LOS LINKS (MAP STUDIES-RELEVANT POINTS TO BE CHECKED FOR PATH PROFILING )Contour interval: It may be at intervals of 5,10, 20 M or more.Bench Marks and other heights: It is required to ascertain the HASL of site in question.Roads, cart tracks, foot paths: For approach to site and to look around for any obstruction on both sides in a hop.Dams, rivers, lakes and other reflecting bodies: For any reflection points in a hop.Hills, sand dunes, rocky slopes, cliffs: For any critical obstruction points (OB).Town, villages, towers, chimneys: For calculating OB points.Communication Towers, Broadcasting stations, TV stations, Airports: For checking interference from other media.

SURVEY OF LOS LINKSTRANSFER OF TERRAIN DATAIN THE SOFTWARE MODULES TERRAIN PROFILE IS PREREQUISITE. THIS CONSISTS OF A TABLE OF DISTANCE AND ELEVATION BETWEEN TWO SITES OF ANY HOP. TERRAIN PROFILE IS CREATED IN THE SOFTWARE MODULE BY ANY METHOD. AFTER DETAILED STUDY OF MAPS AND ROUTE SURVEY MANUAL ENTRY OF CO-ORDINATES, ALTITUDES AND DISTANCES FROM TOPOGRAPHICAL MAPS. SOFTWARE WILL CREATE A PROFILE.MANUAL ENTRY OF CO-ORDINATES AFTER SITE VISITS, SOFTWARE HAVING A MAP SOURCE OF THE REGION WILL READ FROM TERRAIN DATA BASE AND CREATE A PROFILE. TERRAIN PROFILE MODIFICATIONSTERRAIN PROFILES TAKEN FROM MAP SOURCES USUALLY SHOW LESS ALTITUDES AT STEEP HILL TOPS THERE BY INCREASING THE TOWER HEIGHTS. THIS TYPE OF ERROR CAN BE CORRECTED BY ACTUALLY VISITING THE HILL TOP AND CHECKING THE HEIGHT BY HIGH RESOLUTION ALTIMETER.

SURVEY OF LOS LINKS (DETAILED SURVEY - LIST OF INSTRUMENTS)Laptop with software tool and map source loadedGlobal positioning system (GPS map 76-s or GPS-V)Digital or analogue THEODOLITE/TELESCOPE with compass as an attachmentDigital altimeter 0.5 m resolutionHigh resolution binoculars (Stinger-German) 25 Km rangeDigital Camera - SonyWALKI-talkie 1.2 GHz rangeWALKI-talkie VHF rangeDigital or Analogue compassHeliograph/Mirrors/Lamps for Line of Sight Tests

SURVEY OF LOS LINKS (DETAILED SURVEY - LIST OF INSTRUMENTS)Topographical Maps 1:50,000 (Best) For preliminary work out 1:2,50,000 or large scale maps are helpful. In hilly areas where contours are too close 1:25,000 maps are useful.Measuring tape 5 and 50 m.ROTRING scale 1:100, 125, 200, 250, 500, 750Reporting Performa : To be completed before leavingMagnifying glassStationary itemsTopographical instrumentsLadders, Poles, flags, first aid kit, Helmets, safety belts, shoes, water, Identity cards, letter of authority. Balloons with flags at 1 M interval

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN MIRROR TEST)Mirrors required for mirror tests: A perfect way of cross checking LOS.Two mirrors are scratched in the shape of a red cross as shown.Scratched portions are joined back to back, faces are out side.

Size of the mirror shouldbe such, that, it can be heldIn the hand. Mirror is held in hand and light of Sun is allowed to fall on the mirror. Sun light will be seen on the Palm and its reflection in the mirror. Now, the mirror is so adjusted, that, it is directed towards the direction of other station whose Azimuth is known and mirror is tilted such, that, parallax is Removed Between rays falling on the palm and its reflection in theMirror. The person at other siteCan see reflected signal, if LOSIs there.This test is very usefulFor cross checking of LOS.Useful in Metros having highrise buildings and map studyhas no relevance.Between two hill tops, wheredetailed maps are not availableand many critical obstructions are seen.If LOS is there, one can see mirror up to hundreds of Kms.

Reflection side of Mirror - 1Reflection side of Mirror - 2Scratched side of Mirror 1 & 2

SURVEY OF LOS LINKS (DETAILED SURVEY GPS APPLICATIONS)Measurements of exact latitude, longitude and altitude of site or for bench marking.Measurements of areas without triangulation.Oceanic and en route navigation.Precise airfield and landing aid locations.Direct routing of aircraft for fuel saving.Monitoring air craft locations in flight.Search and rescue.Tracking and recovering stolen vehicles.Offshore drilling research.Location of containers in marine terminals.Maintaining security of VIPs.Train control and collision avoidance.Hydrographic surveying.Placing and controlling satellites in orbit.

SURVEY OF LOS LINKSGPS MAP 76 SGPSMAP 76 S IS A GPS AND MAPPING TOOL..THE S STANDS FOR SENSORS BECAUSE IT INCORPORATES A GPS RECEIVER, BAROMETERIC ALTIMETER AND AN ELECTRONIC COMPASS THAT DELIVER PRECISE LOCATION, ELEVATION AND BEARING INFORMATION.THE UNIT CAN TAKE A BASE MAP WITH A PLENTY OF MEMORY (24 MB) FOR DOWNLOADING MAP SOURCE DATA,IT IS WAAS (WIDE AREAAUGUMENTATION SYSTEM) ENABLED PRODUCT. COLLECT DATA FROM THE REFERENCE STATIONS AND CREATE A GPS CORRECTION MESSAGE. THIS CORRECTION IS APPLIED TO THE WAAS- ENABLED GPS RECEIVERS.

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN) Path design: the basic purpose in engineering a radio relay path in microwave range is to achieve a path which will meet the requirements for long term medium noise and also ensure, that, outages due to fading, below the predetermined value is minimized.Regardless of system size, for proper system operation, it is essential for each hop to have adequate clearances under all atmospheric conditions. To determine clearances, the actual topography of the path and also the height location of obstacles along the path, such as multistoried buildings, chimneys, trees, water bodies are taken into account.In a relatively flat country a practical rule of thumb is, that, repeater spacing are generally limited to 25-40 Km with tower heights up to 100 M. Actually, it depends on the topography of terrain. Can any one imagine, that, LOS communication to two terminals which are at a distance of 28 Km is possible with six hops having 3 active and 3 passive repeaters*.

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN)Determining precise co-ordinates, ground elevation (HASL), pinpointing potential obstacles on the point-to-point microwave path is a critical part of the design process. Path survey consists of five basic steps.Step one-site documentation:Site location maps to be studied thoroughly to obtain best access route to the siteOn the way to site make note of the distances and time taken from a well known reference point-mettle road- un-mettle road-cart road-foot path right up to the site. Description of accessibility to site is very important for the visit by future teams.Re-location of site if required If it is existing site detailed information may have to be collected from the concerned agency viz existing tower, equipment room, power plant lay outs and their details etcAll collected data to be re-confirmed

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN)Step two-site location verification: if site is new it is to verified from maps, THEODOLITE, electronic distance/height meter, known bench mark position. After proper verification of the site following data is to be collected.Site co-ordinates: six digit co-ordinates to be marked. Cross checked by GPS, maps.HASL: cross checked from near by bench mark, barometric altimeter of 0.5 m resolution, maps and GPS.Marking of tower center from minimum three reference points with bearing angle from north and distance- near by hill top, chimneys, buildings, transmission tower or any permanent structure. This is again important for the visit by future teams.Marking of preferably true north/otherwise magnetic north*.Marking of azimuth (Map) of each antenna and checking of near end obstructions: use THEODOLITE, prismatic compass and distance height meter. Tower height, antenna heights and AZIMUTHAL angles.

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN)Types and sizes of antennas.Type and length of transmission lines.Transmitter output power.Receiver input level, receiver threshold level and requirement of fade margin.Check on space diversity requirements.Number of main and stand by transmitters and receivers.Laptop/small computer can be very handy at site.Operating frequencies for future equipments.Take photographs of site, which may be useful for identification in future.Take note of the type of soil and soil samples can be taken for laboratory testing. This will be useful for economical design of the tower.

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN)If site is existing, complete lay-out of site is to be made.Existing tower: Type and height of towers, guyed, mast. Take photos.Type, heights, AZIMUTHAL angles of each antenna and availability of space for the type and at proposed height for new antennas.Availability of space for proposed transmission lines on the run way and at wave guide entry point to equipment room.If there is some problem for items at Para 2 & 3, proposal to be submitted in report.Existing equipment, power plant rooms:Type of existing equipments, their operating frequencies & power etc. Lay out to be drawn.Type of power plant, capacity, existing loads and spare capacity also in case solar power is used.Take photos for various equipments.

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN)Step three-identification of critical points along the path.On the maps two sites are joined by a thin straight line.Determine the height, width of all obstructions along the path and HASL at each point for all potential obstructions. Record the man made obstructions, trees, chimneys etc. all above HASL at 1-2 km Intervals, specially record center point obstruction.Allow for future growth of trees and other vegetations for minimum 10 years.Visit every likely critical point to ascertain its height and check other parameters.Determine the width of water bodies, other reflecting points falling along the route.Take mirror tests if after calculations, it is found, that, it is feasible*.Some clients insist on propagation tests, which is neither a practical nor viable approach*.

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN)Step four-path profile: path profiles are drawn based on the detailed survey report. It can be manually or by computerized software. Hop wise data required is given below.Site names.Co-ordinates of each hop. HASL of each siteHop distance (If co-ordinates are fed to computer software, you get hop distance and azimuthal angles)HASL of each obstruction and its height including near-end obstructions.Clearance criteria being adopted.Say Cl=k 4/3 + 100% ffzAND OR Cl=k 2/3 + 30% FFZFrequency band of operation.With the above parameters antenna heights in each direction of operation can be worked out and hence the tower height at each sight.

SURVEY OF LOS LINKS (DETAILED SURVEY SYSTEM DESIGN)Step five-detailed survey report: the report apart from antenna and tower heights already worked out will need reliability calculations for each hop and for the complete link. Determine following parameters.Transmitter powerSize and gain of antennas for main and diversity operations (if applicable)Type and transmission line losses for main and diversity operations (if applicable)Other lossesReceiver thresholdReceived power of receiverSignal to noise ratioWe get Fade Margin and reliability/availability for each hop.The complete exercise can be worked out manually with the help of a calculator. But now a days different Software's are available for Path Loss Calculations, which has made the job simple for the Engineers.

FEASIBILITY STUDIES ANDREPORT GENERATIONCASE STUDY: Feasibility study was carried out for one of the clients for a route length of 2294 Km and report submitted in 2 months. The detailed survey was carried out by three teams in a months time. Because of the limitations of the client, we had to visit at least two to three times the number of sites for microwave repeaters than we would have visited in normal case*.Client gave repeat order for another 2000 Km after going through this report and analyzing the recommendations.

FEASIBILITY STUDIES ANDREPORT GENERATIONCONTENTSCHAPTERDESCRIPTIONLINE DIAGRAMSURVEY AT A GLANCE1. INTRODUCTION2. ORGANIZATION OF THE SURVEY3.METHODOLOGY USED IN SURVEY4.ENGINEERING AND TECHNICAL CONSIDERATIONS5.RESULTS AND PRESENTATION6.RECOMMENDATIONS7.SITE DETAILS

FEASIBILITY STUDIES ANDREPORT GENERATIONCONTENTSCHAPTERDESCRIPTION8.HOP DETAILS8.1PATH PROFILES8.2REFLECTION POINT PROFILES8.3TOWER HEIGHT CALCULATION SHEET8.4RELIABILITY CALCULATION SHEET9.LINK DETAILS9.1GEOGRAPHICAL INFORMATION9.2TOWERS AND AERIALS9.3REFLECTION POINTS9.4INTERFERENCE CALCULATIONS9.5FREQUENCY PLAN9.6OUTAGE TABLE9.7 SYNOPTIC OF THE LINK10.TECHNO ECONOMIC JUSTIFICATION

FEASIBILITY STUDIES (Line Diagram)

LONG= LONG= LONG= LONG= LAT = LAT = LAT = LAT =++++73M/673M/773M/1173M/1473M/1579A/279A/679A/1179A/15ABCDKmKmKmGIVE BEARING ANGLES A-B & B-AAS PER ACTUAL DATA RESULTSGIVE HOP DISTANCES AS PER DATA RESULTSNOT TO SCALETYPICAL EXAMPLE

FEASIBILITY STUDIES(SURVEY AT A GLANCE)FOLLOWING INFORMATION CAN BE GIVEN IN A TABULAR FORM:SL.NO.1.STATION NAMEBELMURIOWNERCLIENT NAMEHASL (M)11LONGITUDE 88 08 53 E LATITUDE22 56 12 NANTENNA HEIGHT (M) TOWARDS80.2 AND 70.2 HOWRAH83.4 AND 73.4 BURDWANAZIMUTH (DEGREES)159.32 AND 323.24HOP DISTANCE (Km)43.75 AND 46.61TOWER HEIGHT (M)90MAP NOS79B/1REMARKSIF ANY, SAY AIR STRIP NEAR BY

FEASIBILITY STUDIES ANDREPORT GENERATIONIntroduction: Brief is given about the clients floating of an enquiry, submission of the bid by the consultant and subsequent letter of award to carry out feasibility study etc.Details of officers involved in technical discussions and feasibility survey works.From clients sidea)Corporate Officeb)Regional Officec)Field coordinatorsd)Survey coordinatorsFrom Consultants sideFeasibility study was carried out for 2294 Km route length in the states of Orissa, West Bengal and Assam.Details of links are given say,A-B=169 KmB-C=176 Km and so on

FEASIBILITY STUDIES ANDREPORT GENERATIONClients Requirements: Technical specifications and B.O.Q given by the client specified, that, wide band communication systems needs to be established between various control centers/substations of eastern region.Media of communication to be through Microwave System, wherever feasible.End terminals to be located at the stations given in the BOQ and Repeaters to be located in any of the manned 33/66/132/220 KV sub-stations on the route.In case the Microwave either becomes non-feasible or becomes much costlier due to large number of repeaters, fiber optics is to be considered.Optical Fiber Cable to run over 400/220 KV transmission lines between end terminals. Repeater if any has to be considered in any of the manned 33/66/132/220 KV sub-stations to the extent possible, failing which repeaters have to be located on the 400/220 KV transmission lines with Solar Power.

FEASIBILITY STUDIES ANDREPORT GENERATIONConstraints:Since repeater (R/R) sites became non-negotiable, it became necessary to carry out the field survey first by making a visit to terminal stations and proposed R/Rs on any 33/66/132/220 KV sub-stations.In the process no of R/R sites to be visited became much more (2-3 times), than, if R/Rs could be negotiable.2.Organization of the Survey: The survey for this feasibility study was carried out for one month by three different teams simultaneously to meet time schedule of the client.Each site (terminals and proposed R/Rs) was visited and map study carried out on the Survey of India Maps of scale 1:50,000. Six digit coordinates were marked by Global Positioning System (GPS) and cross checked on maps.Survey related data was collected for the sites and capacity of system data collected from representatives of the client.After elimination of non-feasible/extra sites, the selected sites were marked on the site plans and brought forward in the feasibility report.

FEASIBILITY STUDIES ANDREPORT GENERATIONThe survey of sites was carried out bearing in mind, that, existing towers shall be shared wherever available and feasible for the best usage of available national resources. However, if permission to share the tower is not agreed upon, nearest sites may be chosen for the erection of tower as per minimum height given in the report.An integrated communication system of 8 Mbps in the frequency band of 2.3 2.5 GHz was considered for Microwave Systems to cater for Voice and Data Communication for the entire network, whereas 34 Mbps OPGW/ADSS cable was considered, where Microwave was either non-feasible or it becomes costly due to more repeaters were coming in the section or tower height was more than 100 M.

FEASIBILITY STUDIES ANDREPORT GENERATION3.METHODOLOGY USED IN SURVEY: Each team used following instruments.Global Positioning System (GPS)TheodolitePrismatic CompassAltimetersBinocularsCameraTopographical InstrumentsRodometerSet of maps 1:2,50,000 and 1:50,000 scaleROTRING scale and necessary stationary itemsApart from clients representative, It was necessary to take a local person to act as a guide to show us different sites.

FEASIBILITY STUDIES ANDREPORT GENERATIONFollowing information was collected and points kept in mind during survey.Determination of sitesSix digit coordinates by GPS and cross checking on mapsHASL i.e. Altitude was checked by Altimeter, GPS and crosschecked on mapsExact location of plot, lay out of the station, orientation and collection of site dataAccessibility to site, by taking references from known pointsLocation, altitude and height of obstacles in each hop.Antenna heights and in turn Tower heights. Towers were kept as low as possible but up to a limit of 100 M.For this clearance criteria given by the client was kept in mind0.3 FFZ for K=2/31.0 FFZ for K=4/3, whichever was more stringent (Up to 44 Km)Space Diversity was proposed on some of the hops either due to reflection point falling on surface of water or length of hop (not meeting desired reliability)Space diversity antenna's proposed at a spacing of 150 , which comes to 20 M.

FEASIBILITY STUDIES ANDREPORT GENERATIONENGINEERING AND TECHNICAL CONSIDERATIONS:Clients requirement of varied telecommunication facilities amongst various dedicated service stations located on existing sites operating in 2.3 to 2.5 GHz band.The scheme falls under the category of light capacity routes, still its engineering and design demands careful consideration to ensure high quality, stability and reliability of the entire route.Objective is to achieve a path, which will meet requirements for long term noise and ensure, that, outage due to fading is below predetermined values.Radio Engineer has to work with many different factors, some of which interact with each other, but he has to come up with solutions which are feasible both technically and economically.It is essential for each hop to have adequate clearance under all atmospheric conditions. For this, the actual topography of the path and also obstacles along the path such as multistoried buildings, chimneys, trees, water bodies and other tall structures will have to be taken into account. In relatively flat country R/R spacing is 25-30 Km and Tower height up to 100 M, economy plays a major role for this height limitation. (In HBJ gas pipe line project this limit was crossed with the result weight of 100 M tower was around 85 MT, where as that of 127 M tower was around 185 MT, increasing enormously cost of foundation and tower material)

FEASIBILITY STUDIES ANDREPORT GENERATIONMap engineering and site selection:Usually topography of an area is extensively studied before going to the field.In this case, since R/R sites were non-negotiable, there was no choice but to visit the sites first and mark them on the maps.All the sites visited were marked on the maps, traveling along each path, collecting information about the type, size, location and characteristics of obstacles, such as, buildings, trees, chimneys, water bodies, low lying areas, river beds, lakes, hills and anticipated critical points. Preliminary profiles were made.Map engineering was carried out on Survey of India maps 1:50,000 scale with contour intervals at 10-20 M.Work out all the alternatives in the night, eliminate non-feasible and extra sites, take decisions before proceeding further.Terminals were fixed by the client, repeaters were to be selected from a number sub-station choices.Engineer had to exercise a great deal in selection of repeater sites for the proposed study to meet the path design requirements with regard to:

FEASIBILITY STUDIES ANDREPORT GENERATIONClearance criteria: Following criteria was adopted for this scheme.1.0 F at K=4/3 ( more stringent up to 44 Km)0.3 F at K=2/3 (more stringent beyond 44 Km)Free Space Loss=92.44 + 20 log10 F + 20 log10 Dwhere F is in GHz and D is in Km.Space Diversity: Vertical antenna space diversity was proposed in few links, wherever it was found necessary for improving the link reliability. Clearance criteria adopted for space diversity antenna was K4/3+0.6F.Reflection point: Due care was taken to avoid reflection, but in one case link was across a dam, in which case space diversity was proposed. This was the only case where, space diversity was proposed due to reflection and not because hop was long.

PARAMETERS FOR PATH LOSS CALCULATIONS(TOWER HEIGHT CALCULATIONS)COMPARISON FOR CLEARANCE CRITERIA BETWEEN (K4/3+1.0F) AND (K2/3+0.3F) WHICHEVER IS CRITICAL

FEASIBILITY STUDIES ANDREPORT GENERATION5.RESULTS AND PRESENTATION: Results of survey were displayed in three parts.I)Site Details: a)A data sheet giving:-Geographic coordinates and altitudeStation to be servedReference of map on which station is locatedAccess sketch with reference to surrounding cities and villagesDetails if site is existingInformation about energyInformation about vegetation and soilInformation about towers, aerials, azimuth and more precisely type of tower and its heightDiameter and height of antenna

FEASIBILITY STUDIES ANDREPORT GENERATIONb)Orient Sheet Giving:-A part of the map with indication on site location and direction to last, next and other sites (if any)Orientation of the site with reference to some permanent marking i.e. hill tops, buildings, chimneys, transmission lines or any permanent structure, with approximate distances and azimuthal angle from north. Since all the sites were existing, orientation was not given in the report.c)Site lay out:-Site lay-out at different scales, giving by drawing all the information about the site as found from either, site lay out or information collected from clients representatives. Proposed location of Tower with respect to control Room was given.

FEASIBILITY STUDIES ANDREPORT GENERATIONII)Hop Details: Path profiles:- Path profiles have been drawn on flat earth by computer for clearance criteria already specified. In case of space diversity links lower antenna height is mentioned. Clearance criteria adopted for space diversity antenna was 4/3+0.6 F.Reflection point profiles:- Due care was taken to ensure, that, the reflection points do not fall on water surface/reflecting surfaces by adjusting antenna heights by using PATH LOSS software program Version 3.0.Tower height calculation sheet:- The desired information already collected from the field during survey was fed to the computer software to arrive at the tower heights for each hop. Reliability calculation sheet:- Going through the clients specifications, equipment is selected which are fed to the computer along with antenna gains and transmission line losses figures. Reliability figures were checked and in case, desired results were not achieved, changes were made to meet the targets.

FEASIBILITY STUDIES ANDREPORT GENERATIONIII)Link Details:Geographical informationTowers and aerialsReflection pointsInterference calculationsFrequency planOutage tableSynoptic of the linkThe above information in the tabular forms was given for the entire route length.Wherever, microwave links were not feasible, Fiber Optics was suggested.

FEASIBILITY STUDIES ANDREPORT GENERATIONRecommendations:Selection Criteria:- Considering the present and future requirements of client for voice and data, feasibility study was carried out for 8 Mbps Microwave System in 2.3 to 2.5 GHz frequency band on all feasible links.Optical Fiber System was recommended where Microwave was not either feasible or it was becoming more costly due to more repeaters.Considering the overall requirements of the client, as specified in the tender and discussion with their representatives from time to time, following parameters were kept in mind for preparing this report.MICROWAVE:Overall reliability was kept better than CCIR limits.Network to provide 120 digital channels of 64 Kbps.Fade margin has been kept 30- 40 dB.Reliability has been worked out for 8 Mbps at 2.4 GHz.OPTICAL FIBER:Optical Fiber repeater spacing was limited to 100 Km.Optical Fiber Repeaters to be located at 33/66/132/220 KV sub-stations as for as possible, in the absence of which it was to be kept on tower near road crossings with provision of solar power.

FEASIBILITY STUDIES ANDREPORT GENERATIONMICROWAVE SYSTEMS:Merits:-Optimum use of the capacity by the user. 2.3 to 2.5 GHz are low capacity systems.Project can be completed quickly on available sub-stations. Delay in acquiring land is avoidable.Microwave is slightly cheaper as long as repeater spacing is between 25-40 Km.Demerits:-Site clearance from SACFA takes time.WPC is conserving frequencies and sparing minimum slots.There is tendency of Microwave becoming costlier than Fiber Optics.In spite of best design of Microwave System, there could be chances of interference from other users.Land acquisition, Tower foundation and erection are time consuming and could cause delay if sub-soil is rocky or have high water table.In close proximity of EHT lines, tower erection could hazard and need extra care.Since repeater stations shall be erected in the campus of other agencies, there could be coordination problems during execution. Operation and maintenance of the system.

FEASIBILITY STUDIES ANDREPORT GENERATIONOPTICAL FIBER SYSTEM:Merits:-Can be installed on existing or future power lines easily.In case no dropping of channels is required it can be installed end to end between two terminals.Optical fiber is safe, since it is over the EHT lines.Number of repeaters are far and few, lesser the equipment lesser the maintenance problems.Optical fiber cable maintenance can be done along with the EHT lines.The system provides unlimited capacity and is easily expandable. Extra capacity can be leased out and generate extra revenue.Demerits:-Optical fiber repeaters are to be located in any of the sub-stations failing which they were to be located on 220/440 KV transmission lines with solar power, which could be a vulnerable point in remote areas.Failure of transmission towers is likely to disrupt the communication for a longer period.

FEASIBILITY STUDIES ANDREPORT GENERATIONRECOMMENDATIONS:Feasibility study was carried out for 2294 Km route length to see, if Microwave Systems were feasible on these routes. Though microwave links were feasible on 1334 km as indicated in the report. It was recommended, that, optical fiber cable could be the best communication media for the entire region for the following reasons.Single media of communication is the best from execution, operating and maintainability point of view. Microwave cannot be single media, since it is non-feasible on many routes.Separate clearances for Frequency and SACFA not be taken.Co-ordination, operational and maintenance problems with other agencies, where microwave repeaters shall be falling could be avoided.Interface problems amongst different media can be avoided.Microwave system will be used only by nodal agency, whereas if optical fiber is used, spare fiber can be leased out to other agencies, thereby generating extra revenue.For microwave systems Royalty and License fee to be paid to DOT is a recurring expenditure.OFC system has unlimited channel bandwidth. Future expansion is easy and relatively less expensive, unlike Microwave Systems.

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE PARTICULARS CALCUTTA)Site Particulars: The information for each site to be noted in tabular form.Site Name: CalcuttaLink Name: Calcutta-DurgapurLongitude: 88 21 03 ELatitude: 22 29 49 NAltitude: 6 MOperating Frequency: 2400 MHzMap Number: 79/B-6Scale: 1:50,000Access to sit: Existing otherwise details to be given.Room for Equipment: Available in existing building.Type of soil: Normal soil with sand at top.Vegetation: GrassyEnergy: AC and -48 V availableTower:Type SSHeight 100 M (Existing)Antenna:TypeDiameterHeightAzimuthTowardsDAX-61.8 M50 M325.33Howrah15.Remarks: Permission for using existing 100 M tower of DOT to be taken by client.

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE MAP AND SITE ORIENTATION)Map No: 79/ BAzimuth AngleDistanceA=55750 MB=1201.2 KmC=3007.9 Km325.33HOWRAH1:50,000 SCALE MAPCALCUTTABuildingHill Road crossingABCProposed Tower centerNorth

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE PARTICULARS BELMURI)Site Particulars: The information for each site to be noted in tabular form.Site Name: BELMURILink Name: Calcutta-DurgapurLongitude: 88 08 53 ELatitude: 22 56 12 NAltitude: 11 MOperating Frequency: 2400 MHzMap Number: 79/B-1Scale: 1:50,000Access to sit: Existing otherwise details to be given.Room for Equipment: Available in existing building.Type of soil: Normal.Vegetation: GrassyEnergy: AC available, DC not availableTower:Type SSHeight 90 MAntenna:TypeDiameterHeightAzimuthTowardsDAX-103 M80.2 M159.32HOWRAHDAX-103 M70.2 M159.32HOWRAHDAX-124 M83.4 M323.24BURDWANDAX-82.4 M73.4 M323.24BURDWAN

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE LAYOUT PLAN BELMURI) BELMURI SITE: (NOT TO SCALE)CONTROL ROOMSHEDRAMP20 M20 MPROPOSED LOCATION FOR 90 M TOWERSWITCH YARDROADRAILWAY TRACK50 MN

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE PARTICULARS BURDWAN)Site Particulars: The information for each site to be noted in tabular form.Site Name: BURDWANLink Name: Calcutta-DurgapurLongitude: 87 52 32 ELatitude: 23 16 25 NAltitude: 28 MOperating Frequency: 2400 MHzMap Number: 73/M-15Scale: 1:50,000Access to sit: Existing otherwise details to be given.Room for Equipment: New.Type of soil: Normal.Vegetation: GrassyEnergy: AC available, DC not availableTower:Type SSHeight 100 MAntenna:TypeDiameterHeightAzimuthTowardsDAX-124 M96.5 M143.13BELMURIDAX-82.4 M86.5 M143.13BELMURIDAX-124 M97.0 M299.00MANKARDAX-103 M44.2 M291.41Galsi (alternative to MANKAR)15.Remarks: 100 M cable required from new equipment room to control room.

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE LAYOUT PLAN BURDWAN)BURDWAN SITE: (NOT TO SCALE)ROADKATWABURDWANPROPOSED 100 M TOWER(OPTION-I)PROPOSED100 M TOWER(OPTION-II)SWITCH YARDCONTROLROOM(SINGLE STORY)OH CABLE70 MN

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE PARTICULARS MANKAR)Site Particulars: The information for each site to be noted in tabular form.Site Name: MANKARLink Name: Calcutta-DurgapurLongitude: 87 32 07 ELatitude: 23 25 49 NAltitude: 60 MOperating Frequency: 2400 MHzMap Number: 73/M-11Scale: 1:50,000Access to sit: Kacha road (Motor able).Room for Equipment: New.Type of soil: Normal.Vegetation: GrassyEnergy: Not availableTower:Type SSHeight 50 MAntenna:TypeDiameterHeightAzimuthTowardsDAX-124 M48 M116.42BURDWANDAX-103 M42 M313.76PARULIA15.Remarks: Since this is new site, suitable space be kept for Eqpt. room and Tower.

FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)(SITE LAYOUT PLAN MANKAR)MANKAR SITE: (NOT TO SCALE)DVC WATER SUPPLYFOR IRRIGATIONMANKAR RURAL HOSPITALPROPOSED 50 M TOWERPROPOSED TELECOM BUILDINGPROPOSED LAND FOR 132 KV SUB STATIONNMOTOR ABLE ROAD

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(PATH PROFILE BELMURI - BURDWAN)BELMURILATITUDE 22 56 12 NLONGITUDE 88 08 53 EAZIMUTH 323.24 DEG.ELEVATION 11 M AMSLANTENNA CL 83.4, 73.4 M AGLBURDWANLATITUDE 23 16 25 NLONGITUDE 87 52 32 EAZIMUTH 143.13 DEG.ELEVATION 28 M AMSLANTENNA CL 96.5, 86.5 M AGLPATH LENGTH 46.61 KmFREQUENCY=2400 MHzK=0.66, 0.66% F=30.00, 20.0020406080100120140160005101520253035404596.5 28 M11 M83.4

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(REFLECTION POINT PROFILE BELMURI - BURDWAN)BELMURI BURDWAN HOP:051015202530354045020406080100120140160REFLECTION PLANE DEFINED BETWEEN 0.00 AND 46.61 KmREFLECTION POINT LOCATION AT 22.3 KmFREQUENCY 2400 MHzFRESNEL ZONE 30.0 %F1

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(TOWER HEIGHT CALCULATION SHEET BELMURI-BURDWAN)

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(RELIABILITY CALCULATION SHEET BELMURI - BURDWAN)

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(PATH PROFILE BURDWAN - MANKAR)BURDWANLATITUDE 23 16 25 NLONGITUDE 87 52 32 EAZIMUTH 296.56 DEG.ELEVATION 28 M HASLANTENNA CL 93.2 M AGLMANKARLATITUDE 23 25 49 NLONGITUDE 87 32 07 EAZIMUTH 116.42 DEG.ELEVATION 60 M HASLANTENNA CL 48 M AGL

PATH LENGTH 38.87 KmFREQUENCY 2400 MHzK = 1.33% F = 100.00

051015202530204060801001203560 ASL48 AGL93.2 AGL28 ASLM

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(REFLECTION POINT PROFILE BURDWAN - MANKAR)REFLECTION PLANE DEFINED BETWEEN 0.00 AND 38.87 KmREFLECTION POINT LOCATION AT 24.2 KmFREQUENCY 2400 MHzFRESNEL ZONE 100 %F10510152025303538.8720406080100120

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(TOWER HEIGHT CALCULATION SHEET BURDWAN - MANKAR)

FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)(RELIABILITY CALCULATION SHEET BURDWAN - MANKAR)

FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)(GEOGRAPHICAL INFORMATION)FOLLOWING INFORMATION CAN BE GIVEN IN A TABULAR FORM:SL.NO.1.STATION NAMEBELMURIOWNERCLIENT NAMEHASL (M)11LONGITUDE 88 08 53 E LATITUDE22 56 12 NAZIMUTH (DEGREES)159.32 TOWARDS HOWRAH323.24 TOWARDS BURDWANTOWER HEIGHT (M)90HOP DISTANCE (Km)43.75 TOWARDS HOWRAH46.61 TOWARDS BURDWANREMARKSIF ANY SAY AIR STRIP NEAR BY

FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)(TOWERS AND AERIALS)FOLLOWING INFORMATION IS GIVEN IN A TABULAR FORM:

S.N.STATIONFROMSTATION TOANT.DIA.(M)ANT.HT. (M)AZIMUTHDEGREETX LINE(M)1CALCUTTAHOWRAH1.850325.33702HOWRAHCALCUTTABELMURI1.83.352.684.2,74.2145.31339.3873105, 953BELMURIHOWRAHBURDWAN3.34.0,2.480.2,74.283.4,73.4159.32323.24101, 91104, 944BURDWANBELMURIMANKAR4.0, 2.44.096.5, 86.593.2143.13296.56117, 1071165MANKARBURDWANPARULIA4.03.048.041.9116.42313.7668626PARULIAMANKAR3.055.0133.6975

FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)(REFLECTION POINTS)

FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)(FREQUENCY PLAN)26.96 Km35.33 Km46.61 Km43.75 Km9.75 KmPARULIAMANKURBURDWANBELMURIHOWRAHCALCUTTAf1f1f1f1f1f1f1f1f1f1VHVHVABCDEF5085851005055

FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)(INTERFERENCE CALCULATIONS)

FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)(OUTAGE TABLE)

FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)(SYNOPTIC OF THE LINK)29.96 Km35.33 Km46.61 Km43.75 Km9.75 KmPARULIAMANKARBURDWANBELMURIHOWRAHCALCUTTA55 M50 M100 M85 M85 M50 M55M41.9M48M93.2M96.5M86.5M83.4M73.4M80.280.2M70.2M84.2M74.2M52.6M50.0M

FEASIBILITY STUDIES AND REPORT GENERATION(TECHNO - ECONOMIC JUSTIFICATION){(CALCUTTA PARULIA (DURGAPUR)}

GUILDLINES(SURVEY FOR LINE OF SIGHT LINKS)Formation of team for surveyCollection of: Relevant survey instruments/tools etc.Topographical maps 1:25,000/50,000 scale with contour at 10 M.Site Profiles/DrawingsData on existing towers and availability of space Antennas/Equipment.Customers specifications and requirements.Information about location of Radar Sites and Airports.Information about existing Terrestrial systems in the area.

GUILDLINES(SURVEY FOR LINE OF SIGHT LINKS)Map Study as per tender requirements for Co-ordinates, altitude, terrain conditions and LOS conditions.Site survey:- Is carried out for each site to determine:Access road and approach to siteLongitude, latitude, altitude and availability & stability of power supply.Soil bearing capacity, weather conditions, availability of Infrastructure etc. Hop Survey: Map study and terrain between two site of each hop is thoroughly trekked to determine:Altitude and heights of Near end obstructions, 1-2 Km points along the LOS route for each hop.Water logging and other reflecting areas.Likely interference from nearby Radar and Airport sites.

GUIDELINES(SURVEY FOR LINE OF SIGHT LINKS)Preparation of Drawings:Site lay out planPath profiles: Clearance criteria (as per clients requirements) , heights of critical points (as per survey) to be taken into account.Finalization of:Tower Heights:-are calculated for each hop. K-factor, first fresnel zone clearance, critical points, reflection points and diversity option are main factors.Received level and reliability calculations as specified. 9.Finalization of System Design: Transmitter Power, location of Terminals, Repeaters, Antenna Size/Type/Gain, TX line-Type/Loss.

TRANSMISSION PLANNING GUIDELINESBHARTI CELLULAR LIMITED-EASTERN REGION1.TRANSMISSION DESIGN CRITERIA (ACCESS PLANNING):POWER TRANSMIT: 18 dBm FOR FLEXIHOPPER 18 GHz RADIOS.POWER TRANSMIT: 20 dBm FOR FLEXIHOPPER 15 GHz RADIOS.TRAFFIC CAPACITY: CAN BE 4E1, 8E1 OR 16E1.RADIO OPERATING MODES: SINGLE (1+0) FOR SITES IN LOOP/RING. HSB (1+1) FOR REMOTE LOOP SITES. FOR SPUR LINKS WILL BE (1+0) BUT WILL BE (1+1) IF TWO MORE SITES DEPENDENT ON IT.1E1 TO BE COSIDERED FOR CITY SITES.RECEIVER THRESHOLD POWER AT BER: -81 dBm FOR 15GHz 16X2.RECEIVER THRESHOLD POWER AT BER: -83 dBm FOR 15GHz 8X2.RECEIVER THRESHOLD POWER AT BER: -86 dBm FOR 15GHz 4X2.INTERFERENCE MARGIN: 3 TO 4 Db.RELIABILITY OF LINKS: 99.995 FOR ACCESS LINKS AND 99.999 FOR BACKBONE.

TRANSMISSION PLANNING GUIDELINESBHARTI CELLULAR LIMITED-EASTERN REGIONFADE MARGIN: 35-40 dB.RAIN REGION: N (120 mm/h)ANTENNA SIZES: 0.6 M AND IF REQUIRED 1.2 M.ANTENNA HEIGHT: MAX. 40 M.ANTENNA SIZES FOR BB LINKS: 1.8 M/ 2.0 M.ANTENNA HEIGHT FOR BB LINKS: 80 M. PREFERENCE IS TO ESTABLISH AS MANY AS LOOPS AS POSSIBLE, SINCE IT PRODUCES 10-100 FOLDS IMPROVEMENT IN THE LINK AVAILABILITY COMPARED TO SINGLE NON-PROTECTED LINK.Microwave Radio TypeMaximum Hop Distance (Km)Antenna Sizes for both SitesFlexiHopper 15G,H Pol. 120 mm/hr.V Pol. 120 mm/hr. 16E1 (1+0)0.6 m1.2 m0.6 m1.2 m5.0 Km7.5 Km6.5 Km10.5 KmFOR LOS STUDY 100 % F.F.Z. CLEARANCE AT K=4/3, WILL BE CONSIDERED FOR ACCESS NETWORK PLANNING.

TRANSMISSION PLANNING GUIDELINESBHARTI CELLULAR LIMITED-EASTERN REGION2. BACKBONE TRANSMISSION DESIGN CRITERIA:POWER TRANSMIT: 24 dBm FOR CERAGON STM-1 RADIOS.POWER TRANSMIT: 23 dBm FOR FLEXIHOPPER 7 GHz RADIOS.RADIO OPERATING MODES: HSB (1+1) FOR ALL LINKS.SPACE DIVERSITY WILL BE USED FOR ALL BACKBONE SDH LINKS. FOR SPUR LINKS NOKIA WILL PERFORM LINK AVAILABILITY CALCULATIONS.TRAFFIC CAPACITY: STM-1 FOR Ceragon 7GHz (28 MHz BW) and 16E1 for Nokia FlexiHopper 7 GHz (28MHz BW).RECEIVER THRESHOLD POWER AT BER10 raised to power minus 6: -68 dBm for Ceragon radios.RECEIVER THRESHOLD POWER AT BER TEN RAISED TO POWER MINUS 6: -81dBmFOR FLEXIHOPPER 7 GHz 16X2 RADIOS.LINK RELIABILITY: 99.999 AND FOR SECTION 99.995.

TRANSMISSION PLANNING GUIDELINES

RAIN ZONE: 120 MM/HR. RAIN INTENSITY (0.01 %).FADE MARGIN: 35-40 DbMAXIMUM HOP LENGTH IN 7 GHz FOR STM-1 CAPACITY IS GIVEN.SL.NO. FREQ. LINK CONFIG.ANTENNA SIZES1.2 M1.8 M2.4 M

1 7 GHz (1+0)13.5Km17.4Km19.4Km (1+1)HSB12.0Km15.7Km17.9Km (1+1)HSB WITH S/D17Km28Km35Km FOR LOS STUDY, 100 % FIRST FREZNEL ZONE CLEARANCE AT K=4/3 AND 60 % F.F.Z. CLEARANCE ATK=2/3 WILL BE CONSIDERED FOR BACK BONE PLANNING.

SURVEY, SYSTEM DESIGN, ENGINEERING AND BID SUBMISSION FOR LOS AND OFC LINKSCONCLUSION: The course has been developed with the objective, that, Engineers come out of colleges with more theoretical knowledge and are not aware of actual field problems. International Exposure experienced during last 20 years on similar assignments have been shared.

SURVEY, SYSTEM DESIGN, ENGINEERING AND BID SUBMISSION FOR LOS AND OFC LINKSTick () on ones (a) Free space loss increases if frequency is increased and decreases if distance is increased.(b) Free space loss decreases with the increase of both distance and frequency.(c) Free space loss increases with the increase of both distance and frequency.2.(a) First Fresnel Zone Radius increases with increase in distance and decreases with increase in frequency.(b) First Fresnel Zone Radius decreases with increase in distance and increases with increase in frequency.(c) First Fresnel Zone Radius decreases both with the with increase in distance and in frequency.For standard atmosphere value of K is: (a) K=1 (b) K=4/3 (c) K=2/3In a hop Earth Bulge is maximum at (a) the ends (b) the center (c) the critical obstructed point.Reflection point area lies between a K factor of: (a) K=1 and K=Infinity.(b) K=4/3 and K=2/3 (c) K=7/6 and K=5/12.

SURVEY, SYSTEM DESIGN, ENGINEERING AND BID SUBMISSION FOR LOS AND OFC LINKS6.For a hop if all other parameters are kept same, for K=4/3 tower height will be (a) less (b) more (c) equal in comparison with K=2/3.If frequency diversity is used, the separation between two frequencies is generally kept (a) 12-20 % (b) 2-3% (c) 5-10%.Separation between Space Diversity antennas is to the tune of:(a) 100-200 (b) 5-10 (c) 20-40 .CCIR defines availability of radio relay links over hypothetical reference circuit of 2500 Km route as (a) 97.9 % (b) 79.7 % (c) 99.7 %.India is located between following co-ordinates:(a) Latitude 8 - 36 N, Longitude 68 - 96 E(b) Latitude 8 - 36 S, Longitude 68 - 96 W(c) Latitude 8 - 36 N, Longitude 68 - 96 WAzimuthal angles or bearing is measured from:(a) True South (b) True North (c) True East12.Maximum height of line of sight towers is normally limited to:(a) 200 M (b) 300 M (c) 100 M

SURVEY, SYSTEM DESIGN, ENGINEERING AND BID SUBMISSION FOR LOS AND OFC LINKSReliability of a LOS hop can be improved by:(a) Space Diversity (b) Increasing the hop distance (c) Decreasing tower height.14.On a straight link when single frequency is used in tandem, normally change of polarization is recommended every: (a) 3rd hop (b) hop (c) 5th hop (d) depends on the configuration of the route.

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