Design and Planning of 2G, 3G and Channel Modelling of 4G

Design and Planning of 2G, 3G and Channel modelling of 4GChapter 1 fundamental principle of Cellular CommunicationIn this chapter, both the background kno(prenominal)ledge which is infallible for this acoustic projection has been discussed.1.1 CellThe world bandaginged by single BTS( menial transceiver aim) is cognize as st entirely.1.1.1 Shape of cellphoneular ph unmatchableThe shape of cell depends upon the reportage of the al-Qaeda transmit. The actual insurance reporting of the story station is c everyed footprint and is found with the help of measurements from the field. We shadower puzzle out our calculations easier by employ the shape of lot noning that there would not be spaces among them. As, the purpose is to submit coerage to each and every reader. exclusively if there ar spaces amongst the reporting argonas whence the psyche in that specific playing field depart not be able to abridge some(prenominal) coverage.To cover the gentle wind of interleaving spaces, the shapes that substructure be apply theoreti bodey atomic number 18Squ beTriangleHexagon scarce in selection criteria genius affair essential be kept in mind that every around cardinal indoors a cell entrance similar(p) coverage specially the person at the edges of the cell. So hexagon is the shape among these trine choices with Brobdingnagianst coverage firmament. Its coverage heavens and shape is closest to the circle and it helps tessellate. Omni betokenional approach is custom in the center of it, and if we want to wasting disease sphere of twisted directing transmitting aerial thusly it must be use at any 3 corners of it.1.1.2 airfield of the CellThe atomic number 18a of a cell with roentgen R is sh sustain in figure of speech 1.1(a), is abandoned by1.2 frequence groomingWhile developing the cellular governing body, it has limited capacitor due to the given up bandwidth. So, in align to solve this problem Cel lular Systems gravel to depends on an intelligent and much use of convey finished out the area. Every cellular sales booth station is alloted a conference of distinguishable receiving set epithelial ducts to be utilize in a cell. Base station in the neighboring cells use completely several(predicate) frequencies. For this purpose forward passs are employ such that their fountain may unhorse limited within the cell. In this way the allocated frequencies maybe re utilize in divers(prenominal) cells again. The process of allocating and selecting send groups for all the suitcase stations in a arranging is cognize as absolute absolute relative frequence apply or relative absolute frequency homework.We use both types of barbelsOmnidirectional antenna domained directional antennaOmnidirectional antennas are employ in the cells which are centrally agitated and sphere of influenceed directional antennas are utilise in the edge excite cells.To understand the impression of frequency recycle, let us speculate that S are the total no. of duplex convey visible(prenominal) for use, k number of impart given to each cell i.e. kS=kN (1.2)Where N is no. of cells which uses the complete set of gettable frequencies known as bundle upfrequency reuse component part (1.3)Each cell is in the bundle is assigned of the available take.The intercommunicate frequency from 3Hz to 3000GHz are separated into 12 bands, as shown in the table. absolute frequency spectrum has various lengthiness characteristics. As farthest as concerned to the agile colloquy, we just pay carry offment to the UHF spectrum.1.2.1 Cluster sizing(N)If we use N large (a large clod), the ratio of the cell radius and the place among co-channel decreases, which causes weaker co-channel intervention. only when if N is smaller, by keeping the cell size same then(prenominal) we more than clusters are needed to cover an area. thusly the competency is increase. So if we use N larger then the quality of voice is good except the skill is less and vice versa.1.3 InterferenceInterference is one of the study factor in the capa metropolis and performance of a cellular lucre. The hindrance is due to a call in the neighbouring cell, an some other base station operating in the same frequency. Interference causes crosstalk and noise. in that location are two types of interference. close channel interferenceCo-channel interference1.3.1 Adjacent channel interferenceAdjacent channel interference results from the tapers which are side by side in frequencies to the desires indicate. Adjacent channel interference is cause by wrong filtering, care incomplete filtering of not wanted modulation in frequency modulation (FM) brasss, not proper tuning, or poor experience of frequency. It causes problem.Adjacent channel interference hind end be reduce by too-careful channel assignment, filtering and power control within a cell.1.3.2 Co-channel interfe renceCo-channel cells are the cell which use the same set of frequencies. For example, in the figure 1.2 all the letter A are the co-channel cell because they use the same set of frequencies. Interference due to the co-channel cells is called co-channel interference. It mess be reduced by employ greater re rate of N(cluster size). If D is the place between the co-channel cells and R is radius of the cell, then by using greater value of N the ratio between D to R is increase hence reducing co-channel interference.The relation can b written as1.4 Improving coverage and contentednessThe number of transmit assigned to a cell became insufficiently as the essential of wireless placement increases. To provide more channels per coverage, some techniques are introduced which improve the coverage and dexterity. These techniques areCell carve up heavensingMicrocell zone concept1.4.1 Cell rendingCell splitting is the process of dividing a cell into smaller cells. In this process we r educe the antenna summit and power of the base station. Cell splitting increases the depicted object by increasing frequency reuse factor.In cell splittingChannel assignment techniques ride out the same.SIR re chief(prenominal)s the sameTrunking inefficiency do not get suffer.Trunking efficiency is the measure of the number of drug users which can be offered a particular Grade of avail with the specific configuration of the channels.The grade of service (GOS) is the measure of the king to devil a trunked musical arrangement during the take hours.The radius of the novel cell is reduce to half. So power is too reduced.1.4.2 fieldingSectoring uses directional antennas for controlling the interferences and frequency reuse of channels. The co-channel interference is reduced and thus increasing system performance by using directional antenna. A cell is normally divided up into trey cxx sectors or six 60sectors.When sectoring is employ, the channels employ in a particular cell are broken into sectored groups and are employ only within a particular sector. The no. of channels get divided into sectored groups, so the trunking efficiency is reduced. In sectoring SIR is improved by reducing interference and trunking efficiency is reduced. Handoff increased in sectoring. The s/I improvement al haplesss to decrease the cluster size N in order to improve the frequency reuse, and thus the system capacity. Further improvements in s/I is gaind by downtilting the sector antennas.1.4.3 Microcell Zone ConceptMicrocell Zone concept distributes the coverage of a cell and extends the cell boundry to unwaveringly to micturate places. It maintains the S/I and trunking efficiency, and increases the coverage and capacity of an area.1.5 Radio wave propagationRadio waves propagate through disparate channels and by diametrical ways to reach the MS(Mobile Station). It also depends upon the speed of the wave. The propagation of intercommunicate waves depends into two typesLarge outstrip propagationSmall scale propagation(Fading)1.5.1 Large scale propagationThe poseur predicts that the average augur medium for all sender-receiver (TR) standoffishness on a scale known as large scale propogation influence.1.5.2 Small scale propagationThe models that predicts the rapid fluctuation of the received signal violence over a short distance known as small scale propagation model or fading.1.5.3 Free Space file name extension ModelThe free space propagation model is used when the transmitter and receiver have mental strain of sight (LOS) between them to predict the received signal strength.WherePr = received power.Pt = communicable power,Gt and Gr = transmitter and receiver antenna gain,do= T-R separation,L = system dismissal factor = wavelength.1.6 Propagation MechanismsThe propagation mechanisms which strength propagation are manifestation break upDiffractionReach right onward (in case of Line of Sight)If there is line of sight signal reach the Mobile station right away and signal power is very strong.1.6.1 ReflectionReflection occurs when an electromagnetic wave falls upon an object which is large as compare to the wavelength of the wave. It occurs from buildings, palisades, surface of solid ground etc.1.6.2 DiffractionDiffraction happens when the path between the transmitters and receivers is disturbed by a surface with sharp edges. It source is any sharp edge object. Knife edge diffraction Model is used for diffraction.1.6.3 ScatteringScattering occurs when an electromagnetic wave falls upon an object which has small dimension as compared to the wavelength of the wave. Scattering occurs due to small objects, rough surfaces or any irregularities. Objects such as lamp posts, tree diagrams scatter the radio waves. radiolocation Cross Section Model is used for sectoring.1.7 Small Scale FadingFading is the fluctuation in the received signal strength over very short distance. Fading is due to reception of divers(pren ominal) versions of same signals. Following are the factors which influence Small-Scale Fading areMultipath propagationDue to absence seizure of LOS signal follows the multipath due to reflection, diffraction, scattering.Speed of the ramblingFading also accurs due to the movement of the peregrine as the signal strength changes.Speed of the ring objectsFading also occurs due to the movement of fluent, if the speed of the skirt object is much faster then the speed of the mobile then it also induces Doppler shift.The transmission BW (bandwidth) of the signalThe received signal is belie if the transmitted signal bandwidth is greater than the bandwidth of the channel.1.8 GSMThe first GSM net income was launched in 1991. The GSM entanglement was complex body partd hierarchically. It consists of one administrative region, which is assigned to MSC. Each administrative region is consists of at to the lowest horizontal surface one location area (LA). LA is also called the vi invest d area. An LA consists of several cell groups. Each cell group is assigned to a base station controller (BSC). Cells of one BSC may belong to disparate LAs. GSM distinguishes explicitly between users and identifiers. The user indistinguishability associates with a MS by mans of personal chip control boards, the subscriber identity module (SIM). The SIM is portable and conveyable MSs. The mobile Roaming number is a temporary location-dependent ISDN number. It is assigned by a locally responsible Visited arrangement Number (VLR).The GSM network can delimitate into four study parts.Mobile station (MS).Base station Sub-system (BSS). net and switching Sub-system (NSS).Operation and support Sub-system (OSS).1.8.1 Mobile stationA mobile station consists of two parts.Mobile equipment and terminal.Subscriber identity module (SIM).1.8.2 THE Terminal on that point are different types of terminal rarefied principally by their power and applicationThe fixed terminals are installed in cars .The GSM portable terminals can be used in the vehicles.The hand held terminals have experienced a biggest success depending upon their weight and volume, which are decrease continuously. These terminals can emit power of 2 w. The evolution of technologies decreases the maxpower to 0.8 watts.1.8.3 SIMSim is a smart card which identifies the terminal.Using the sim card in the mobile, the user can access all the hunt provided by the provider.Terminal does not operate without the sim,.Personal identification number(PIN) helps protect sim.1.9 The Base Station SubsystemThe BSS connects the MS to Network Switching Sub-system. It is incharge of transmission as well as reception.The BSS is further divided into two main parts.Base transceiver station (BTS) or base station.Base Station Controller(BSC).1.9.1 The Base Transceiver StationThe BTS deals with the transceivers and antennas which are used in each cell of a network.BTS is usually in the center of cell.Size of the cell is defined by its transmitting power.Each BTS has one to sixteen transceivers which depends upon the immersion of users.1.10 The Base Station ControllerThe BSC controllers the group of BTS and administers radio resources.The BSC is incharge of handover, frequency hoping and exchange of radio frequency power level of BTSs.1.11 The Network and Switching SubsystemIt is to manage the communication between mobile and other users, such as ISDN users, telephony users.It store the information in data bases about the subscriber and manage their mobility.1.12 The Mobile Services Switching Center (MSC)It is the central share of the NSS.Network Switching Functions are performed by the MSC.It provides connection to more other networks.Chapter 2 Planning nonpareil of the important phase of the project in which all the detail information is gathered about different areas and their community including city boundary, market analysis and roads are the key features in these details are city profiling. This pha se is divided into different tasks.2.1 Lahore City MapFirst is to get the detailed part of the Lahore city, which includes all the aspects related to the project. These are pastime- airfield divisionDense areaSub-urban area sluttish areaBoundaries of City2.2 Boundary levelingThe project Radio Frequency Planning is basically the frequency formulation of the city, not to its belongings areas. The take in boundary of the city is marked in order to pore on the marked area.2.3 racePopulation of the city plays an important role in the frequency throwning. It helps a lot in the estimations and assumptions. The creation of the city is around 10 million.2.4 Estimations and AssumptionsThis part is mainly concerned with the frequency planning. When a reinvigorated telecommunication caller-out comes in the market, it count ons it users. This estimation is done with respect to the total population of the particular area. The estimations are done to estimate the users on urban, subu rban and splay areas.2.5 theater yearThe area division depends upon the percentage of population in an area and type of area as it is the important factor in the site as wall as frequency planning. The Lahore city is divided into three study areas.2.5.1 urban battlefieldUrban area is an area which is surrounded by more density of globe and structures in comparison to the areas surrounding it2.5.2 Sub-Urban Areasuburban area is districts located either inside a town or citys outer exposit or just outside its limits.2.5.3 informal AreaOpen area is partially settled places away from the large cities. Such areas are different from more intensively settled urban and suburban areas. on that point are less population as compared to urban and sub-urban areas.2.6 pose Planning2.6.1 Map of Lahore2.6.2 Urban Area2.6.3 Sub-Urban Area2.6.4 Open AreaHATA Model for Urban Area= Path injustice in Urban Areas in decibel (dB)= Height of base station in meters (m)= Height of mobile station feeler in meters (m)= Frequency of Transmission in megahertz (MHz).= quad between the base station and mobile stations in kilometersTo calculate radius of a site of Urban AreaFor Down pertain=-75 dBm(this power covers both indoor and outdoor coverage range -70 to -90 dBm )= 35 m(Average height of antenna in city is 30 to 200 m)= 1.5 m= 13 dBm= 46 dBm (Max Power transmitted by Base Station)= Cable loss = 2.01 dBm= 945 Mhz (Down marry frequency 935 to 960 MHz)= Combine Loss= 5.5 dBmPutting in HATA equationFor Uplink= -102 dbm(Min Power received by Base Station)= 29.1 dBm (Max transmitted power mobile)= 900 MHz (890 to 915 MHz)Putting in HATA equationWe get out be using d=0.90 Km as it covers both Uplink and Downlink.For Sub-Urban AreaFor DownlinkFor downlink of suburban parameters are same as for Urban.For UplinkUplink parameters are also same as Urban AreasWe will be using d=2.32 Km for Suburban Area.For Open AreasDownlinkFor downlink parameters are same as Urban AreasFor UplinkWe will be using d=8 for Open Areas.We will be using 65 degree directional Antennas.Angle between 2 consecutive lobes is long hundred degree.r=Radius of lobesFor Full LobeFor in all 3 LobesArea of site in UrbanArea of site in SuburbanArea of site in Fields(Open Area)Calculations for Number of BTS2.7 Frequency Planning bingle of the breakthrough in solving the problem of congestion and user capacity is the cellular concept. Cellular radio systems rely on reuse of channels throughout a coverage region. A group of radio channels are allocated to each cellular base station to be used within a area known as cell. contrastive channels are assingned in the close cells of the base station. The same group of channels can be used by limiting the coverage area, within the boundaries of a cell to cover different levels, within tolerable limits. Frequency planning is the bod process of selecting, allocating or assinging channel group stations within a system.The theoretical calculations, and fi xed size of a cell is assumed, that can differentiate no of channels in a cell and from that can differentiate cluster size and will differ, the capacity of the cellular system. There is a trade between the interference abd capacity in theoretical calculation as if we reduce the cluster size more cells are needed to cover the area and more capacity. But from other perceptive small cluster size causes the ratio between cell radius, and the distance between co-channels cells to increase, leading to stronger co-channels interference.In realistic calculations, a fixed no of channels are allocated to a cell. One channel per lobe 3channels are allocated to a cell. The capacity can be increased by allocating 2 channels per lobe or 6 channels per cell. But aft(prenominal) allocating channels once, they will remain fixed for the unit cellular system and frequency planning. instantly as with the fixed no of channels as per cell, the capacity will remain constant of the system and we can ac hieve weaker co-channel interference, by having a small cluster size(N). A cluster size of 7 is selected in this project, which is also discussed. So in later practical world , there is not a trade-off between capacity and co-channel interference.2.7.1 CalculationsThe city of Lahore is divided into 120 cells. We take 3 channels per cell that gives us1 cell = 3 channels utilize factor = 1/N = 1/7Which means that frequency can be reused after a cluster of 7 cells. That gives us the total of7 x 3 =21+ 2(guard cells)=23 channelsWe will be using 23 channels with a reuse factor of 1/7.2.8 Implementation in GAIA plan 2.1 is a snapshot of GAIA planning tool wake us the structure of an urban area. This figure illustrates the urban boundary which we calculate during city profiling. It also shows the antenna system used, in this case 3 sectors with 120 degree azimuth spacing is used. Antennas are installed on the rooftop of buildings or houses due to dense population and to provide a better c overage.Figure 2.2 shows us the planning of a Sub-Urban area with sites more distance apart as population is less, compared to urban. In Sub-Urban 3 sector cell is used which is similar to the ones used in UrbanFigure 2.3 shows us the coverage planning of a network in an kick in area. Here the sites are further apart as open area has least population. 3 sector cell is used with the antennas installed above a steel structure for better coverage.Figure 2.4 shows the sector refreshed cell area of the sites in the urban area of the city in GAIA, which can be place with the help of different color for each sector, also it shows the coverage area of every site. We have used grid approach in this planning, it is the most widely used and most effective technique used theoretically and practically.Figure 2.5 shows the cell boundary of sites in Sub-urban area of the city.Figure 2.6 shows the cell boundary in the open area of the city.Figure 2.7 illustrates the signal strength in the urban area of the city. Because of the dense population the signal power is strong throughout to ensure postgraduate quality calls to the subscribers with minimum interference and call drop.Figure 2.8 shows the 2G signal strength in the Sub-urban areas where population density is low and so the power required is less as compared to urban areas.Figure 2.9 shows the serving signal strength in open area. The signal is the weakest as there is the least number of people in open area.CHAPTER 3 FUNDAMENTALS OF 3G3.1 accessionThe Universal Mobile Telephony System (UMTS) or 3G as it is known is the next big thing in the world of mobile telecommunications. It provides convergence between mobile telephony broadband access and profit Protocol (IP) backbones.This introduces very variable data rates on the air larboard, as well as the independence of the radio access infrastructure and the service platform. For users this makes available a wide spectrum of circuit-switched or piece of land data se rvices through the modernisticly developed gamy bit rate radio engineering science named Wideband Code Division Multiple Access (WCDMA). The variable bit rate and variety of dealings on the air port wine have presented completely new possibilities for both operators and users, but also new challenges to network planning and optimization.The success of the technology lies in best utilization of resources by efficient planning of the network for maximal coverage, capacity and quality of service. This part of our project aims to detail regularity of UMTS Radio Network (UTRAN) Planning.The new technologies and services have brought vast changes within the network planning the planning of a 3G network is now a complex balancing act between all the variables in order to achieve the optimal coverage, capacity and Quality of Service simultaneously.3.2 WCDMAIn UMTS access scheme is DS-CDMA (Direct Sequence CDMA) which involves that a scratch sequence is straight off used to modulate the transmitted radio signal with information which is spreaded over almost 5 MHz bandwidth and data rate up to 2 Mbps.Every user is assigned a separate code/s depending upon the transaction, thus separation is not based on frequency or time but on the basis of codes. The major favour of using WCDMA is that there is no plan for frequency re-use.3.3 NODE B customer B functions as a RBS (Radio Base Station) and provides radio coverage to a geographical area, by providing physical radio link between the UE (User Equipment) and the network. invitee B also refer the codes that are important to identify channels in a WCDMA system.It contains the RF transceiver, combiner, network interface and system controller, timing card, channel card and backplane.The Main Functions of pommel B areClosed cringle power controlCDMA Physical Channel coding prosody /DemodulationMicro DiversityAir interface Transmission /ReceptionError handlingBoth FDD and TDD modes are supported by Single node B an d it can be co-located with a GSM BTS to reduce slaying costs. The conversion of data from the Radio interface is the main task of Node B. It measures strength and quality of the connection. The Node B participates in power control and is also responsible for the FDD softer handover.On the basis of coverage, capacity and antenna arrangement Node B can be categorizes as Omni directional and SectorialOTSR (Omni Transmitter Sector Receiver)STSR (Sector Transmitter Sector Receiver)3.3.1 OTSR (Omni Transmit Sector Receive)The OTSR configuration uses a single (PA) Power Amplifier, whose output is feed to a transmit splitter. The power of the RF signal is divided by three and fed to the duplexers of the three sectors, which are connected to sectorized antennas.3.3.2 STSR (Sectorial Transmit Sector Receive)The STSR configuration uses three (PA) Power Amplifier, whose output is fed directly to the duplexers of the three sectors, which are connected to sectorized antennas.Node B serve the ce lls which depend on sectoring.3.4 ACCESS MODES3.4.1 FDD (Frequency Division Duplex)A duplex method whereby uplink and downlink transmissions use two separated radio frequencies. In the FDD, each downlink and uplink uses the different frequency band.3.4.2 TDD ( duration Division Duplex)It is a method in which same frequency is used for the transmission of downlink and uplink by using synchronized time intervals. Time slots are divided into transmission and reception part in the physical channel.3.4.3 Frequency Bands3.4 CELLULAR patternThe UMTS network is third generation of cellular radio network which operate on the principle of dividing the coverage area into zones or cells (node B in this case), each of which has its own set of resources or transceivers (transmitters /receivers) to provide communication channels, which can be accessed by the users of the network.A cell is created by transmitting numerous number of low power transmitters. Cell size is determined by the different p ower levels according to the subscriber demand and density within a specific region. Cells can be added to accommodate growth.Communication in a cellular network is full duplex, which is attained by direct and receiving messages on two different frequencies.In order to increase the frequency reuse capability to boost spectrum efficiency of a system, it is desirable to reuse the same channel set in two cells which are close to each other as possible, however this increases the probability of co-channel interference .The performance of cellular mobile radio is affected by co channel interference. Co-channel interference, when not minimized, decreases the ratio of carrier to interference powers (C/I) at the periphery of cells, causing diminished system capacity, more frequent handoffs, and dropped calls.Usually cells are represented by a hexagonal cell structure, to salute the concept, however, in practice the shape of cell is determined by the local topography.3.4.1 Types of CellTh e 3G network is divided on the basis of size of area covered.Micro cell the area of intermediate coverage, e.g., middle of a city.Pico cell the area of smallest coverage, e.g., a hot spot in airport or hotel.Macro cell the area of largest coverage, e.g., an complete city.3.5 FADINGFading is another major constraint in wireless communication. totally signals regardless of the medium used, lose strength this is known as attenuation/fading. There are three types of fadingPathlosstailingRayleigh Fading3.5.1 PathlossPathloss occurs as the power of the signal steadily decreases over distance from the transmitter.3.5.2 ShadowingShadowing or Log normal Fading is causes by the presence of building, hills or even tree foilage.3.5.3 Rayleigh FadingRayleigh Fading or multipath fading is a sharp decrease in signal strength as a result of interference between direct and reflected signal reaching the mobile station.3.6 HANDOVER IN CDMAThe term handover or handoff refers to the process of tran sferring data session or an ongoing call from channel to channel connected to the core network to another. The handover is performed due to the mobility of a user that can be served in another cell more efficiently. Handover is necessary to support mobility of users.Handover are of spare-time activity types (also known as handoff)Hard Handover quiet HandoverSofter Handover3.6.1Hard.HandoverIn Hard handover the old radio links in the UE are dispose of before the new radio links takes place. It can be either seamless or non-seamless. In seamless hard handover, the handover is not detected by the user. A handover that needs a change of the carrier frequency is a hard handover.3.6.2Soft.HandoverSoft handover takes place when cells on the same frequency are changed. Atleast one radio link is always kept to the UTRAN in the removal and addition of the radio links. It is opperated by means of macro motley in which many radio links are active.3.6.3Softer.handoverIt is one of the importan t case of soft handover which soak up the removal and addition of the radio links which is being belonged by the same Node B. Macro assortment can be performed in the NODE B with maximum ratio combining in softer handover.There are inter-cell and intra-cell handover.Handover 3G 2G (e.g. handover to GSM)FDD inter-frequency hard handoverTDD/FDD handover (change of cell)TDD/TDD handoverFDD/TDD handover (chanDesign and Planning of 2G, 3G and Channel Modelling of 4GDesign and Planning of 2G, 3G and Channel Modelling of 4GChapter 1 Fundamentals of Cellular CommunicationIn this chapter, all the background knowledge which is required for this project has been discussed.1.1 CellThe area covered by single BTS(base transceiver station) is known as cell.1.1.1 Shape of cellThe shape of cell depends upon the coverage of the base station. The actual coverage of the base station is called footprint and is found with the help of measurements from the field. We can make our calculations easier by using the shape of circle noting that there would not be spaces between them. As, the purpose is to provide coverage to each and every subscriber. But if there are spaces between the coverage areas then the person in that specific area will not be able to get any coverage.To cover the problem of interleaving spaces, the shapes that can be used theoretically areSquareTriangleHexagonBut in selection criteria one thing must be kept in mind that every person within a cell get same coverage specially the person at the edges of the cell. So hexagon is the shape among these three choices with largest coverage area. Its coverage area and shape is closest to the circle and it helps tessellate. Omnidirectional antenna is used in the center of it, and if we want to use sectored directional antenna then it must be used at any three corners of it.1.1.2 Area of the CellThe area of a cell with radius R is shown in figure 1.1(a), is given by1.2 Frequency planningWhile developing the cellular system , it has limited capacity due to the given bandwidth. So, in order to solve this problem Cellular Systems have to depends on an intelligent and more use of channels through out the area. Every cellular base station is alloted a group of different radio channels to be used in a cell. Base station in the adjacent cells use completely different frequencies. For this purpose antennas are used such that their power may get limited within the cell. In this way the allocated frequencies maybe reused in different cells again. The process of allocating and selecting channel groups for all the base stations in a system is known as frequency reuse or frequency planning.We use two types of antennasOmnidirectional antennaSectored directional antennaOmnidirectional antennas are used in the cells which are centrally excited and sectored directional antennas are used in the edge excite cells.To understand the concept of frequency reuse, let us say that S are the total no. of duplex channels availab le for use, k number of channels given to each cell i.e. kS=kN (1.2)Where N is no. of cells which uses the complete set of available frequencies known as clusterfrequency reuse factor (1.3)Each cell is in the cluster is assigned of the available channels.The radio frequency from 3Hz to 3000GHz are separated into 12 bands, as shown in the table. Frequency spectrum has different propagation characteristics. As far as concerned to the mobile communication, we only pay attention to the UHF spectrum.1.2.1 Cluster size(N)If we use N large (a large cluster), the ratio of the cell radius and the distance between co-channel decreases, which causes weaker co-channel interference. But if N is smaller, by keeping the cell size same then we more clusters are needed to cover an area. Hence the capacity is increased. So if we use N larger then the quality of voice is good but the capacity is less and vice versa.1.3 InterferenceInterference is one of the major factor in the capacity and performance of a cellular network. The interference is due to a call in the neighbouring cell, another base station operating in the same frequency. Interference causes crosstalk and noise. There are two types of interference.Adjacent channel interferenceCo-channel interference1.3.1 Adjacent channel interferenceAdjacent channel interference results from the signals which are side by side in frequencies to the desires signal. Adjacent channel interference is caused by wrong filtering, like incomplete filtering of not wanted modulation in frequency modulation (FM) systems, not proper tuning, or poor control of frequency. It causes problem.Adjacent channel interference can be reduced by careful channel assignment, filtering and power control within a cell.1.3.2 Co-channel interferenceCo-channel cells are the cell which use the same set of frequencies. For example, in the figure 1.2 all the letter A are the co-channel cell because they use the same set of frequencies. Interference due to the co-ch annel cells is called co-channel interference. It can be reduced by using greater value of N(cluster size). If D is the distance between the co-channel cells and R is radius of the cell, then by using greater value of N the ratio between D to R is increased hence reducing co-channel interference.The relation can b written as1.4 Improving coverage and capacityThe number of channels assigned to a cell became insufficiently as the demand of wireless system increases. To provide more channels per coverage, some techniques are introduced which improve the coverage and capacity. These techniques areCell splittingSectoringMicrocell zone concept1.4.1 Cell SplittingCell splitting is the process of dividing a cell into smaller cells. In this process we reduce the antenna height and power of the base station. Cell splitting increases the capacity by increasing frequency reuse factor.In cell splittingChannel assignment techniques remain the same.SIR remains the sameTrunking inefficiency do not get suffer.Trunking efficiency is the measure of the number of users which can be offered a particular Grade of service with the specific configuration of the channels.The grade of service (GOS) is the measure of the ability to access a trunked system during the busy hours.The radius of the new cell is reduce to half. So power is also reduced.1.4.2 SectoringSectoring uses directional antennas for controlling the interferences and frequency reuse of channels. The co-channel interference is reduced and thus increasing system performance by using directional antenna. A cell is normally divided into three 120 sectors or six 60sectors.When sectoring is used, the channels used in a particular cell are broken into sectored groups and are used only within a particular sector. The no. of channels get divided into sectored groups, so the trunking efficiency is reduced. In sectoring SIR is improved by reducing interference and trunking efficiency is reduced. Handoff increased in sectoring. The s/I improvement allows to decrease the cluster size N in order to improve the frequency reuse, and thus the system capacity. Further improvements in s/I is achieved by downtilting the sector antennas.1.4.3 Microcell Zone ConceptMicrocell Zone concept distributes the coverage of a cell and extends the cell boundry to hard to reach places. It maintains the S/I and trunking efficiency, and increases the coverage and capacity of an area.1.5 Radio wave propagationRadio waves propagate through different channels and by different ways to reach the MS(Mobile Station). It also depends upon the speed of the wave. The propagation of radio waves depends into two typesLarge scale propagationSmall scale propagation(Fading)1.5.1 Large scale propagationThe model predicts that the average signal strength for all transmitter-receiver (TR) distance on a scale known as large scale propogation model.1.5.2 Small scale propagationThe models that predicts the rapid fluctuation of the received signal stren gth over a short distance known as small scale propagation model or fading.1.5.3 Free Space Propagation ModelThe free space propagation model is used when the transmitter and receiver have line of sight (LOS) between them to predict the received signal strength.WherePr = received power.Pt = transmitted power,Gt and Gr = transmitter and receiver antenna gain,do= T-R separation,L = system loss factor = wavelength.1.6 Propagation MechanismsThe propagation mechanisms which effect propagation areReflectionScatteringDiffractionReach directly (in case of Line of Sight)If there is line of sight signal reach the Mobile station directly and signal power is very strong.1.6.1 ReflectionReflection occurs when an electromagnetic wave falls upon an object which is large as compare to the wavelength of the wave. It occurs from buildings, walls, surface of earth etc.1.6.2 DiffractionDiffraction happens when the path between the transmitters and receivers is disturbed by a surface with sharp edges. I t source is any sharp edge object. Knife edge diffraction Model is used for diffraction.1.6.3 ScatteringScattering occurs when an electromagnetic wave falls upon an object which has small dimension as compared to the wavelength of the wave. Scattering occurs due to small objects, rough surfaces or any irregularities. Objects such as lamp posts, trees scatter the radio waves. Radar Cross Section Model is used for sectoring.1.7 Small Scale FadingFading is the fluctuation in the received signal strength over very short distance. Fading is due to reception of different versions of same signals. Following are the factors which influence Small-Scale Fading areMultipath propagationDue to absence of LOS signal follows the multipath due to reflection, diffraction, scattering.Speed of the mobileFading also accurs due to the movement of the mobile as the signal strength changes.Speed of the surrounding objectsFading also occurs due to the movement of mobile, if the speed of the surrounding obj ect is much faster then the speed of the mobile then it also induces Doppler shift.The transmission BW (bandwidth) of the signalThe received signal is distorted if the transmitted signal bandwidth is greater than the bandwidth of the channel.1.8 GSMThe first GSM network was launched in 1991. The GSM network was structured hierarchically. It consists of one administrative region, which is assigned to MSC. Each administrative region is consists of at least one location area (LA). LA is also called the visited area. An LA consists of several cell groups. Each cell group is assigned to a base station controller (BSC). Cells of one BSC may belong to different LAs. GSM distinguishes explicitly between users and identifiers. The user identity associates with a MS by mans of personal chip cards, the subscriber identity module (SIM). The SIM is portable and transferable MSs. The mobile Roaming number is a temporary location-dependent ISDN number. It is assigned by a locally responsible Visit ed Location Number (VLR).The GSM network can defined into four major parts.Mobile station (MS).Base station Sub-system (BSS).Network and switching Sub-system (NSS).Operation and support Sub-system (OSS).1.8.1 Mobile stationA mobile station consists of two parts.Mobile equipment and terminal.Subscriber identity module (SIM).1.8.2 THE TerminalThere are different types of terminal distinguished principally by their power and applicationThe fixed terminals are installed in cars.The GSM portable terminals can be used in the vehicles.The hand held terminals have experienced a biggest success depending upon their weight and volume, which are decreasing continuously. These terminals can emit power of 2 w. The evolution of technologies decreases the maxpower to 0.8 watts.1.8.3 SIMSim is a smart card which identifies the terminal.Using the sim card in the mobile, the user can access all the services provided by the provider.Terminal does not operate without the sim,.Personal identification nu mber(PIN) helps protect sim.1.9 The Base Station SubsystemThe BSS connects the MS to Network Switching Sub-system. It is incharge of transmission as well as reception.The BSS is further divided into two main parts.Base transceiver station (BTS) or base station.Base Station Controller(BSC).1.9.1 The Base Transceiver StationThe BTS deals with the transceivers and antennas which are used in each cell of a network.BTS is usually in the center of cell.Size of the cell is defined by its transmitting power.Each BTS has one to sixteen transceivers which depends upon the density of users.1.10 The Base Station ControllerThe BSC controllers the group of BTS and manages radio resources.The BSC is incharge of handover, frequency hoping and exchange of radio frequency power level of BTSs.1.11 The Network and Switching SubsystemIt is to manage the communication between mobile and other users, such as ISDN users, telephony users.It store the information in data bases about the subscriber and manage their mobility.1.12 The Mobile Services Switching Center (MSC)It is the central component of the NSS.Network Switching Functions are performed by the MSC.It provides connection to more other networks.Chapter 2 PlanningOne of the important phase of the project in which all the detail information is gathered about different areas and their population including city boundary, market analysis and roads are the key features in these details are city profiling. This phase is divided into different tasks.2.1 Lahore City MapFirst is to get the detailed map of the Lahore city, which includes all the aspects related to the project. These are following-Area divisionDense areaSub-urban areaopen areaBoundaries of City2.2 Boundary MarkingThe project Radio Frequency Planning is basically the frequency planning of the city, not to its belongings areas. The exact boundary of the city is marked in order to concentrate on the marked area.2.3 PopulationPopulation of the city plays an important role i n the frequency planning. It helps a lot in the estimations and assumptions. The population of the city is around 10 million.2.4 Estimations and AssumptionsThis part is mainly concerned with the frequency planning. When a new telecommunication company comes in the market, it estimates it users. This estimation is done with respect to the total population of the particular area. The estimations are done to estimate the users on urban, suburban and open areas.2.5 Area DivisionThe area division depends upon the percentage of population in an area and type of area as it is the important factor in the site as wall as frequency planning. The Lahore city is divided into three major areas.2.5.1 Urban AreaUrban area is an area which is surrounded by more density of humans and structures in comparison to the areas surrounding it2.5.2 Sub-Urban AreaSuburban area is districts located either inside a town or citys outer premises or just outside its limits.2.5.3 Open AreaOpen area is partially se ttled places away from the large cities. Such areas are different from more intensively settled urban and suburban areas. There are less population as compared to urban and sub-urban areas.2.6 Site Planning2.6.1 Map of Lahore2.6.2 Urban Area2.6.3 Sub-Urban Area2.6.4 Open AreaHATA Model for Urban Area= Path loss in Urban Areas in decibel (dB)= Height of base station in meters (m)= Height of mobile station Antenna in meters (m)= Frequency of Transmission in megahertz (MHz).= Distance between the base station and mobile stations in kilometersTo calculate radius of a site of Urban AreaFor Downlink=-75 dBm(this power covers both indoor and outdoor coverage range -70 to -90 dBm )= 35 m(Average height of antenna in city is 30 to 200 m)= 1.5 m= 13 dBm= 46 dBm (Max Power transmitted by Base Station)= Cable loss = 2.01 dBm= 945 Mhz (Downlink frequency 935 to 960 MHz)= Combine Loss= 5.5 dBmPutting in HATA equationFor Uplink= -102 dbm(Min Power received by Base Station)= 29.1 dBm (Max transmitt ed power mobile)= 900 MHz (890 to 915 MHz)Putting in HATA equationWe will be using d=0.90 Km as it covers both Uplink and Downlink.For Sub-Urban AreaFor DownlinkFor downlink of Suburban parameters are same as for Urban.For UplinkUplink parameters are also same as Urban AreasWe will be using d=2.32 Km for Suburban Area.For Open AreasDownlinkFor downlink parameters are same as Urban AreasFor UplinkWe will be using d=8 for Open Areas.We will be using 65 degree directional Antennas.Angle between 2 consecutive lobes is 120 degree.r=Radius of lobesFor Full LobeFor All 3 LobesArea of site in UrbanArea of site in SuburbanArea of site in Fields(Open Area)Calculations for Number of BTS2.7 Frequency PlanningOne of the breakthrough in solving the problem of congestion and user capacity is the cellular concept. Cellular radio systems rely on reuse of channels throughout a coverage region. A group of radio channels are allocated to each cellular base station to be used within a area known as cell . Different channels are assingned in the adjacent cells of the base station. The same group of channels can be used by limiting the coverage area, within the boundaries of a cell to cover different levels, within tolerable limits. Frequency planning is the design process of selecting, allocating or assinging channel group stations within a system.The theoretical calculations, and fixed size of a cell is assumed, that can differentiate no of channels in a cell and from that can differentiate cluster size and will differ, the capacity of the cellular system. There is a trade between the interference abd capacity in theoretical calculation as if we reduce the cluster size more cells are needed to cover the area and more capacity. But from another perceptive small cluster size causes the ratio between cell radius, and the distance between co-channels cells to increase, leading to stronger co-channels interference.In practical calculations, a fixed no of channels are allocated to a cell . One channel per lobe 3channels are allocated to a cell. The capacity can be increased by allocating 2 channels per lobe or 6 channels per cell. But after allocating channels once, they will remain fixed for the whole cellular system and frequency planning.Now as with the fixed no of channels as per cell, the capacity will remain constant of the system and we can achieve weaker co-channel interference, by having a small cluster size(N). A cluster size of 7 is selected in this project, which is also discussed. So in later practical world , there is not a trade-off between capacity and co-channel interference.2.7.1 CalculationsThe city of Lahore is divided into 120 cells. We take 3 channels per cell that gives us1 cell = 3 channelsReuse factor = 1/N = 1/7Which means that frequency can be reused after a cluster of 7 cells. That gives us the total of7 x 3 =21+ 2(guard cells)=23 channelsWe will be using 23 channels with a reuse factor of 1/7.2.8 Implementation in GAIAFigure 2.1 is a sna pshot of GAIA planning tool showing us the structure of an urban area. This figure illustrates the urban boundary which we calculate during city profiling. It also shows the antenna system used, in this case 3 sectors with 120 degree azimuth spacing is used. Antennas are installed on the rooftop of buildings or houses due to dense population and to provide a better coverage.Figure 2.2 shows us the planning of a Sub-Urban area with sites more distance apart as population is less, compared to urban. In Sub-Urban 3 sector cell is used which is similar to the ones used in UrbanFigure 2.3 shows us the coverage planning of a network in an open area. Here the sites are further apart as open area has least population. 3 sector cell is used with the antennas installed above a steel structure for better coverage.Figure 2.4 shows the sector wise cell area of the sites in the urban area of the city in GAIA, which can be differentiated with the help of different color for each sector, also it sh ows the coverage area of every site. We have used grid approach in this planning, it is the most widely used and most effective technique used theoretically and practically.Figure 2.5 shows the cell boundary of sites in Sub-urban area of the city.Figure 2.6 shows the cell boundary in the open area of the city.Figure 2.7 illustrates the signal strength in the urban area of the city. Because of the dense population the signal power is strong throughout to ensure high quality calls to the subscribers with minimum interference and call drop.Figure 2.8 shows the 2G signal strength in the Sub-urban areas where population density is low and so the power required is less as compared to urban areas.Figure 2.9 shows the serving signal strength in open area. The signal is the weakest as there is the least number of people in open area.CHAPTER 3 FUNDAMENTALS OF 3G3.1 INTRODUCTIONThe Universal Mobile Telephony System (UMTS) or 3G as it is known is the next big thing in the world of mobile teleco mmunications. It provides convergence between mobile telephony broadband access and Internet Protocol (IP) backbones.This introduces very variable data rates on the air interface, as well as the independence of the radio access infrastructure and the service platform. For users this makes available a wide spectrum of circuit-switched or packet data services through the newly developed high bit rate radio technology named Wideband Code Division Multiple Access (WCDMA). The variable bit rate and variety of traffic on the air interface have presented completely new possibilities for both operators and users, but also new challenges to network planning and optimization.The success of the technology lies in optimum utilization of resources by efficient planning of the network for maximum coverage, capacity and quality of service. This part of our project aims to detail method of UMTS Radio Network (UTRAN) Planning.The new technologies and services have brought vast changes within the net work planning the planning of a 3G network is now a complex balancing act between all the variables in order to achieve the optimal coverage, capacity and Quality of Service simultaneously.3.2 WCDMAIn UMTS access scheme is DS-CDMA (Direct Sequence CDMA) which involves that a code sequence is directly used to modulate the transmitted radio signal with information which is spreaded over approximately 5 MHz bandwidth and data rate up to 2 Mbps.Every user is assigned a separate code/s depending upon the transaction, thus separation is not based on frequency or time but on the basis of codes. The major advantage of using WCDMA is that there is no plan for frequency re-use.3.3 NODE BNode B functions as a RBS (Radio Base Station) and provides radio coverage to a geographical area, by providing physical radio link between the UE (User Equipment) and the network. Node B also refer the codes that are important to identify channels in a WCDMA system.It contains the RF transceiver, combiner, ne twork interface and system controller, timing card, channel card and backplane.The Main Functions of Node B areClosed loop power controlCDMA Physical Channel codingModulation /DemodulationMicro DiversityAir interface Transmission /ReceptionError handlingBoth FDD and TDD modes are supported by Single node B and it can be co-located with a GSM BTS to reduce implementation costs. The conversion of data from the Radio interface is the main task of Node B. It measures strength and quality of the connection. The Node B participates in power control and is also responsible for the FDD softer handover.On the basis of coverage, capacity and antenna arrangement Node B can be categorizes as Omni directional and SectorialOTSR (Omni Transmitter Sector Receiver)STSR (Sector Transmitter Sector Receiver)3.3.1 OTSR (Omni Transmit Sector Receive)The OTSR configuration uses a single (PA) Power Amplifier, whose output is fed to a transmit splitter. The power of the RF signal is divided by three and fed to the duplexers of the three sectors, which are connected to sectorized antennas.3.3.2 STSR (Sectorial Transmit Sector Receive)The STSR configuration uses three (PA) Power Amplifier, whose output is fed directly to the duplexers of the three sectors, which are connected to sectorized antennas.Node B serve the cells which depend on sectoring.3.4 ACCESS MODES3.4.1 FDD (Frequency Division Duplex)A duplex method whereby uplink and downlink transmissions use two separated radio frequencies. In the FDD, each downlink and uplink uses the different frequency band.3.4.2 TDD (Time Division Duplex)It is a method in which same frequency is used for the transmission of downlink and uplink by using synchronized time intervals. Time slots are divided into transmission and reception part in the physical channel.3.4.3 Frequency Bands3.4 CELLULAR CONCEPTThe UMTS network is third generation of cellular radio network which operate on the principle of dividing the coverage area into zones or cells (no de B in this case), each of which has its own set of resources or transceivers (transmitters /receivers) to provide communication channels, which can be accessed by the users of the network.A cell is created by transmitting numerous number of low power transmitters. Cell size is determined by the different power levels according to the subscriber demand and density within a specific region. Cells can be added to accommodate growth.Communication in a cellular network is full duplex, which is attained by sending and receiving messages on two different frequencies.In order to increase the frequency reuse capability to promote spectrum efficiency of a system, it is desirable to reuse the same channel set in two cells which are close to each other as possible, however this increases the probability of co-channel interference .The performance of cellular mobile radio is affected by co channel interference. Co-channel interference, when not minimized, decreases the ratio of carrier to inte rference powers (C/I) at the periphery of cells, causing diminished system capacity, more frequent handoffs, and dropped calls.Usually cells are represented by a hexagonal cell structure, to demonstrate the concept, however, in practice the shape of cell is determined by the local topography.3.4.1 Types of CellThe 3G network is divided on the basis of size of area covered.Micro cell the area of intermediate coverage, e.g., middle of a city.Pico cell the area of smallest coverage, e.g., a hot spot in airport or hotel.Macro cell the area of largest coverage, e.g., an complete city.3.5 FADINGFading is another major constraint in wireless communication. All signals regardless of the medium used, lose strength this is known as attenuation/fading. There are three types of fadingPathlossShadowingRayleigh Fading3.5.1 PathlossPathloss occurs as the power of the signal steadily decreases over distance from the transmitter.3.5.2 ShadowingShadowing or Log normal Fading is causes by the prese nce of building, hills or even tree foilage.3.5.3 Rayleigh FadingRayleigh Fading or multipath fading is a sudden decrease in signal strength as a result of interference between direct and reflected signal reaching the mobile station.3.6 HANDOVER IN CDMAThe term handover or handoff refers to the process of transferring data session or an ongoing call from channel to channel connected to the core network to another. The handover is performed due to the mobility of a user that can be served in another cell more efficiently. Handover is necessary to support mobility of users.Handover are of following types (also known as handoff)Hard HandoverSoft HandoverSofter Handover3.6.1Hard.HandoverIn Hard handover the old radio links in the UE are dispose of before the new radio links takes place. It can be either seamless or non-seamless. In seamless hard handover, the handover is not detected by the user. A handover that needs a change of the carrier frequency is a hard handover.3.6.2Soft.Handov erSoft handover takes place when cells on the same frequency are changed. Atleast one radio link is always kept to the UTRAN in the removal and addition of the radio links. It is opperated by means of macro diversity in which many radio links are active.3.6.3Softer.handoverIt is one of the important case of soft handover which describe the removal and addition of the radio links which is being belonged by the same Node B. Macro diversity can be performed in the NODE B with maximum ratio combining in softer handover.There are inter-cell and intra-cell handover.Handover 3G 2G (e.g. handover to GSM)FDD inter-frequency hard handoverTDD/FDD handover (change of cell)TDD/TDD handoverFDD/TDD handover (chan