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Modul 2_LargeScaleFading - WCS

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WIRELESS COMMUNICATION. SYSTEMModul 2 Large Scale FadingFaculty of Electrical CommunicationIT Telkom2012Modul 2 Large Scale FadingSubjecta. Path Loss Modelb. Model Okumura-Hatta, COST 231c. Model Walfish Ikegami, LEEa. Path Loss Modelb. Model Okumura-Hatta, COST 231c. Model Walfish Ikegami, LEEModul 2 Large Scale FadingIntroductionIn general, the received signal at the receiver point is the sum of thedirect signal and the number of signals reflected from various objects. Inmobile communications, reflection will be caused by: Environment Buildings Moving object, for example vehiclesVariation of the magnitude and phase of wave reflectiondepends on the reflection coefficient, the trajectory, and alsodepending on the angle of arrival. Thus, differences in the directsignal and reflected signal is:Modul 2 Large Scale FadingVariation of the magnitude and phase of wave reflectiondepends on the reflection coefficient, the trajectory, and alsodepending on the angle of arrival. Thus, differences in the directsignal and reflected signal is: Amplitude, depending on the magnitude of wave reflectioncoefficient Phase, depending on the phase variation of wave reflectionand path distance difference between the direct wave andreflecting waveThe worst condition occurs when the direct wave and reflection wavehas the same magnitude and different phases 180o. In such conditions, thedirect wave and its reflection will eliminate each other (completecancellation )Wireless Propagation RadioFree Space LossDiasumsikan terdapat satu sinyal langsung (line of sight path) sangat mudah memprediksi dengan free space formulaReflectionTerdapat sinyal tak langsung datang ke receiver setelahmengalami pantulan terhadap object. Mungkin terdapat banyakpantulan yang berkontribusi terhadap besarnya delay.DiffractionPropagasi melewati object yang cukup besar seolah-olahmenghasilkan sumber sekunder, seperti puncak bukit dsb.ScatteringPropagasi melewati object yang kecil dan/atau kasar yangmenyebabkan banyak pantulan untuk arah-arah yang berbeda.Free Space LossDiasumsikan terdapat satu sinyal langsung (line of sight path) sangat mudah memprediksi dengan free space formulaReflectionTerdapat sinyal tak langsung datang ke receiver setelahmengalami pantulan terhadap object. Mungkin terdapat banyakpantulan yang berkontribusi terhadap besarnya delay.DiffractionPropagasi melewati object yang cukup besar seolah-olahmenghasilkan sumber sekunder, seperti puncak bukit dsb.ScatteringPropagasi melewati object yang kecil dan/atau kasar yangmenyebabkan banyak pantulan untuk arah-arah yang berbeda.Modul 2 Large Scale FadingModul 2 Large Scale FadingRadio Propagation MechanismsRStransmitterStreetBuilding BlocksDSR: ReflectionD: DiffractionS: ScatteringreceiverDModul 2 Large Scale FadingModul 2 Large Scale Fading Efek propagasi multipath pada kanal wirelessmobile adalah: Large scale fading Large scale path loss Small scale propagation Large scale path loss Large attenuation dalam rata-rata Daya sinyal terima menurun berbanding terbalik denganpangkat- terhadap jarak , dimana umumnya 2 < < 5(untuk komunikasi bergerak). disebut Mean PathlossExponent Sebagai dasar untuk metoda prediksi pathloss Small scale Flukstuasi sinyal yang cepat disekitar nilai rata-rata(large scale) - nya Doppler spread berhubungan dengan kecepatan fading(fading rate) Penyebaran waktu berhubungan dengan perbedaan delaywaktu kedatangan masing-masing sinyal multipath. Efek propagasi multipath pada kanal wirelessmobile adalah: Large scale fading Large scale path loss Small scale propagation Large scale path loss Large attenuation dalam rata-rata Daya sinyal terima menurun berbanding terbalik denganpangkat- terhadap jarak , dimana umumnya 2 < < 5(untuk komunikasi bergerak). disebut Mean PathlossExponent Sebagai dasar untuk metoda prediksi pathloss Small scale Flukstuasi sinyal yang cepat disekitar nilai rata-rata(large scale) - nya Doppler spread berhubungan dengan kecepatan fading(fading rate) Penyebaran waktu berhubungan dengan perbedaan delaywaktu kedatangan masing-masing sinyal multipath.Modul 2 Large Scale Fading Fading didefinisikansebagai fluktuasi daya dipenerima Karena perilaku sinyalpada kanal multipathadalah acak, makaanalisis fadingmenggunakan analisisprobabilitas stokastik Fading terjadi karenainterferensi atausuperposisi gelombangmultipath yang memilikiamplitudo dan fasa yangberbeda-bedaDefinisi FadingFadingLarge Scale FadingSmall Scale FadingTerdistribusiLognormal Terdistribusi Rayleigh / Rician Fading didefinisikansebagai fluktuasi daya dipenerima Karena perilaku sinyalpada kanal multipathadalah acak, makaanalisis fadingmenggunakan analisisprobabilitas stokastik Fading terjadi karenainterferensi atausuperposisi gelombangmultipath yang memilikiamplitudo dan fasa yangberbeda-bedaModul 2 Large Scale FadingDefinisi : local mean ( time averaged) dari variasi sinyalLarge Scale Fading disebabkankarena akibat keberadaan obyek-obyek pemantul serta penghalangpada kanal propagasi sertapengaruh kontur bumi,menghasilkan perubahan sinyaldalam hal energi, fasa, serta delaywaktu yang bersifat random. Sesuai namanya, large scalefading memberikan representasirata-rata daya sinyal terima dalamsuatu daerah yang luas. Statistik dari large scale fadingmemberikan cara perhitunganuntuk estimasi pathloss sebagaifungsi jarak.Kuat sinyal (dB)JarakDefinisi : local mean ( time averaged) dari variasi sinyalLarge Scale Fading disebabkankarena akibat keberadaan obyek-obyek pemantul serta penghalangpada kanal propagasi sertapengaruh kontur bumi,menghasilkan perubahan sinyaldalam hal energi, fasa, serta delaywaktu yang bersifat random. Sesuai namanya, large scalefading memberikan representasirata-rata daya sinyal terima dalamsuatu daerah yang luas. Statistik dari large scale fadingmemberikan cara perhitunganuntuk estimasi pathloss sebagaifungsi jarak.Modul 2 Large Scale FadingEqual level main & reflected pathLower level reflected pathRx LevelWidebandChannelNarrowbandChannelFrequencyChannel Frequency ResponsettttChannel PulseResponseDirect WaveReflected WaveResultantSinyal multipath juga akan menyebabkan distorsi sinyal / cacat sinyal.Problem ini secara khusus berkaitan dengan bandwidth sinyal yangdigunakan dalam komunikasi mobile, dan juga karena respon pulsayang berbeda dari sinyal multipathEqual level main & reflected pathLower level reflected pathRx LevelWidebandChannelNarrowbandChannelFrequencyChannel Frequency ResponsettttChannel PulseResponseDirect WaveReflected WaveResultantModul 2 Large Scale FadingModul 2 Large Scale FadingKANAL MULTIPATH FADING KANAL MULTIPATH FADINGFADING :Fenomena fluktuasi daya sinyal terima akibat adanyaproses propagasi dari gelombang radio. Pengaruh fading terhadaplevel sinyal terima adalahdapat menguatkan ataupunmelemahkan tergantungphasa dari sinyal resultanmasing-masing path.CADBReceiverTransmitter Pengaruh fading terhadaplevel sinyal terima adalahdapat menguatkan ataupunmelemahkan tergantungphasa dari sinyal resultanmasing-masing path.CADBReceiverTransmitterA: direct pathB: reflectionC: diffractionD: scatteringPRPR_threst0Modul 2 Large Scale FadingMultipath dalam kanal radio menyebabkan :Lingkungan kanal radio mobile ( indoor / outdoor ) seringkalitidak terdapat lintasan gelombang langsung antara Tx danRx, sedemikian daya terima adalah superposisi dari banyakkomponen gelombang pantul masing-masing memilikiamplitudo dan fasa saling independenMultipath Fading , atau Short Term Fading Perubahan yang cepat dari amplituda kuat sinyal Modulasi frekuensi random berkaitan dengan efekDoppler pada sinyal multipath yang berbeda-beda Dispersi waktu (echo) yang disebabkan oleh delaypropagasi multipathModul 2 Large Scale FadingIntroductionWhy is it important to understand the characteristicsof wireless channel ? To determine the most appropriate signal design (source, channelcoding, and modulation) To develop new technologies in the radio signal transmitters andreceivers In multiuser communications, channel access scheme must bedone as efficiently as possible. In cellular systems, coverage of the desired signal is computed asaccurately as possible excess power would result in excessiveinterference as well. In cellular communication systems, to ensure the communicationconnection from cell to cell, then the lowest allowable level to bedetermined.Modul 2 Large Scale Fading To determine the most appropriate signal design (source, channelcoding, and modulation) To develop new technologies in the radio signal transmitters andreceivers In multiuser communications, channel access scheme must bedone as efficiently as possible. In cellular systems, coverage of the desired signal is computed asaccurately as possible excess power would result in excessiveinterference as well. In cellular communication systems, to ensure the communicationconnection from cell to cell, then the lowest allowable level to bedetermined. Ideal Channel Ideal channel passed all the spectrum of the signal without distortion(called BW infinite channel with a 'flat' frequency response for allfrequencies) signal attenuation and the error is only caused by the AWGN (AdditiveWhite Gaussian Noise). Received signal is a deterministic quantity which the characteristicsexpressed by using the statistical properties of the AWGN (Gaussiandistributed).Transmitted bitIdeal channelAWGNdetectionIntroductionModul 2 Large Scale Fading Ideal Channel Ideal channel passed all the spectrum of the signal without distortion(called BW infinite channel with a 'flat' frequency response for allfrequencies) signal attenuation and the error is only caused by the AWGN (AdditiveWhite Gaussian Noise). Received signal is a deterministic quantity which the characteristicsexpressed by using the statistical properties of the AWGN (Gaussiandistributed).Introduction Real channel (Physical Channel) : Physical channel always has a limited bandwidth Only a significant component of the signal spectrum that passedthrough the physical channel, in other words the signal isdistorted Signal bandwidth must be smaller or equal to the coherencebandwidth of the channel for relatively no distortion. The questionis: How to obtain the BW signal is smaller than coherentbandwidth of the channel?Transmitted bitPhysicalChannelAWGNdetectionModul 2 Large Scale Fading Real channel (Physical Channel) : Physical channel always has a limited bandwidth Only a significant component of the signal spectrum that passedthrough the physical channel, in other words the signal isdistorted Signal bandwidth must be smaller or equal to the coherencebandwidth of the channel for relatively no distortion. The questionis: How to obtain the BW signal is smaller than coherentbandwidth of the channel?Introduction(((

ot o= 2m22 ) m m (me21) m ( pProbability Distribution Function (PDF) of a lognormal distributedrandom variable is represented as follows :Modul 2 Large Scale Fadingwherem = normal random variable signal strength(dBm)= Average (mean) signal strength (dBm)om= standard deviationmIntroduction (Free Space Prop. Model) Isotropic antenna: power is distributedhomogeneously over surface area of a sphere.Modul 2 Large Scale Fading Isotropic antenna: power is distributedhomogeneously over surface area of a sphere.Received power is power through effective antennasurface over total surface area of a sphere of radius d(Free Space Prop. Model), continuedThe power density w atdistance d iswhere PTis the transmitpower.24 dPw T=Modul 2 Large Scale FadingThe power density w atdistance d iswhere PTis the transmitpower.R TP Ad P=4 2tThe received power iswith A the `antenna aperture' orthe effective receiving surface area.(Free Space Prop. Model), continuedThe antenna gain GRisrelated to the aperture Aaccording toThus the received signalpower isG R A= 42t2||.|

\|-- -d4GGP=Pd4 14G P=PRTT R22R T R Modul 2 Large Scale FadingThe antenna gain GRisrelated to the aperture Aaccording toThus the received signalpower is 2||.|

\|-- -d4GGP=Pd4 14G P=PRTT R22R T R Received power decreases with distance,PR:: d-2Received power decreases with frequency, PR:: f-2Cellular radio planning: Path Loss in dB:Lfs= 32.44 + 20 log (f / 1 MHz) + 20 log (d / 1 km)Microwave and Satellite Communications .... Friis transmission formula, Assumption: there is only a direct wave from the sender to the receiver Radio link designed for local Fresnell I (R1) are free of obstructions. Highantenna tower at the transmitter and the receiver is determined in such away as to guarantee the line of sight conditions) Km ( ) MHz ( P D log 20 f log 20 45 , 32 L + + =22 Introduction Friis transmission formula, Assumption: there is only a direct wave from the sender to the receiver Radio link designed for local Fresnell I (R1) are free of obstructions. Highantenna tower at the transmitter and the receiver is determined in such away as to guarantee the line of sight conditionsFresnell_Iradius= 2 11 h h 4RModul 2 Large Scale FadingPlain Earth Propagation Model. (Eglis Model) As the basic theory of wave trajectory analysis inmobile communication Key words: there are multiple paths (multipath): 1direct wave and a wave reflection. Analysis of the signal path in mobilecommunications is much different from the LOSmicrowave communications because signals havediffraction, much obstructed, and a lot of reflection.23 Introduction As the basic theory of wave trajectory analysis inmobile communication Key words: there are multiple paths (multipath): 1direct wave and a wave reflection. Analysis of the signal path in mobilecommunications is much different from the LOSmicrowave communications because signals havediffraction, much obstructed, and a lot of reflection.Empirical Model. Derived from measurements and intensive research in an area Attenuation curves are plotted and the results made formulations Popular attenuation formula : Okumura-Hata, dan Walfish Ikegami Another path attenuation models developed by: Lee, Egli, Carey,Longley-Rice, Ibrahim-Parson, etcModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingKarakteristik propagasi pada jaringan bergerak (seluler)berbeda dibandingkan dengan karakteristik propagasipada jaringan tetap. Pada jaringan bergerak fading yangterjadi lebih hebat dan fluktuatif dibandingkan denganjaringan tetap.Untuk menghitung path loss pada propagasi jaringanseluler telah banyak dilaakukan percobaan dan penelitian.Beberapa diantaranya yang sering dipakai adalahUntuk menghitung path loss pada propagasi jaringanseluler telah banyak dilaakukan percobaan dan penelitian.Beberapa diantaranya yang sering dipakai adalah Model Hata Model Walfisch-Ikegami ( COST-231 ) Model Okumura dllModul 2 Large Scale FadingMacrocells In early days, the models were based on empricalstudies Okumura did comprehesive measurements in1968 and came up with a model. Discovered that a good model for path loss was a simple powerlaw where the exponent n is a function of the frequency, antennaheights, etc. Valid for frequencies in: 100MHz 1920 MHzfor distances: 1km 100kmPROPAGATION MODEL In early days, the models were based on empricalstudies Okumura did comprehesive measurements in1968 and came up with a model. Discovered that a good model for path loss was a simple powerlaw where the exponent n is a function of the frequency, antennaheights, etc. Valid for frequencies in: 100MHz 1920 MHzfor distances: 1km 100kmModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingOkumura Model L50(d)(dB) = LF(d)+ Amu(f,d) G(hte) G(hre) GAREA L50: 50th percentile (i.e., median) of path loss LF(d): free space propagation pathloss. Amu(f,d): median attenuation relative to free space Can be obtained from Okumuras emprical plots shown in the book (Rappaport),page 151. G(hte): base station antenna heigh gain factor G(hre): mobile antenna height gain factor GAREA: gain due to type of environment G(hte) = 20log(hte/200) 1000m > hte> 30m G(hre) = 10log(hre/3) hre hre> 3m hte: transmitter antenna height hre: receiver antenna height L50(d)(dB) = LF(d)+ Amu(f,d) G(hte) G(hre) GAREA L50: 50th percentile (i.e., median) of path loss LF(d): free space propagation pathloss. Amu(f,d): median attenuation relative to free space Can be obtained from Okumuras emprical plots shown in the book (Rappaport),page 151. G(hte): base station antenna heigh gain factor G(hre): mobile antenna height gain factor GAREA: gain due to type of environment G(hte) = 20log(hte/200) 1000m > hte> 30m G(hre) = 10log(hre/3) hre hre> 3m hte: transmitter antenna height hre: receiver antenna heightCellular radio planning: Path Loss in dB:Lfs = 32.44 + 20 log f (MHz) + 20 log d (km), , ((

= =L d PPdB PLrt2224log 10 log 10 ) (Modul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingHatta Model Valid from 150MHz to 1500MHz A standard formula For urban areas the formula is: L50(urban,d)(dB) = 69.55 + 26.16logfc- 13.82loghte a(hre) +(44.9 6.55loghte) log dwherefcis the ferquency in MHzhteis effective transmitter antenna height in meters (30-200m)hreis effective receiver antenna height in meters (1-10m)d is T-R separation in kma(hre) is the correction factor for effective mobile antenna height whichis a function of coverage areaa(hre) = (1.1logfc 0.7)hre (1.56logfc 0.8) dBfor a small to medium sized city Valid from 150MHz to 1500MHz A standard formula For urban areas the formula is: L50(urban,d)(dB) = 69.55 + 26.16logfc- 13.82loghte a(hre) +(44.9 6.55loghte) log dwherefcis the ferquency in MHzhteis effective transmitter antenna height in meters (30-200m)hreis effective receiver antenna height in meters (1-10m)d is T-R separation in kma(hre) is the correction factor for effective mobile antenna height whichis a function of coverage areaa(hre) = (1.1logfc 0.7)hre (1.56logfc 0.8) dBfor a small to medium sized cityModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale Fading Daerah urbanModel Hata pada daerah urban berlaku rumus sbb :L50(u)= C1+ C2log ( f ) - 13,82 log (hb) a (hm) + { 44,9 6,55log (hb) } log (d).Dimana :f = frekuensi (MHz)hb= tinggi antena BTS (m)hm= tinggi antena MS (m)d = jarak antara BTS MS (km)C1= 69,55 untuk 400 f 1500= 46,3 untuk 1500 < f 2000C2= 26,16 untuk 400 f 1500= 33,9 untuk 1500 < f 2000f = frekuensi (MHz)hb= tinggi antena BTS (m)hm= tinggi antena MS (m)d = jarak antara BTS MS (km)C1= 69,55 untuk 400 f 1500= 46,3 untuk 1500 < f 2000C2= 26,16 untuk 400 f 1500= 33,9 untuk 1500 < f 2000a(hm) = {1,1log (f) - 0,7} hm {1,56 log(f) 0,8 }Modul 2 Large Scale Fading Daerah dense urbanModel Hata pada daerah urban berlaku rumus sbb :L50(du)= C1+C2log ( f )-13,82 log (hb) a (hm)+{ 44,9 6,55log (hb) } log (d)+CmDimana :f = frekuensi (MHz)hb= tinggi antena BTS (m)hm= tinggi antena MS (m)d = jarak antara BTS MS (km)C1= 69,55 untuk 400 f 1500= 46,3 untuk 1500 < f 2000C2= 26,16 untuk 400 f 1500= 33,9 untuk 1500 < f 2000Cm = 3 dBf = frekuensi (MHz)hb= tinggi antena BTS (m)hm= tinggi antena MS (m)d = jarak antara BTS MS (km)C1= 69,55 untuk 400 f 1500= 46,3 untuk 1500 < f 2000C2= 26,16 untuk 400 f 1500= 33,9 untuk 1500 < f 2000Cm = 3 dBa(hm) = 3,2{ log(11,75hm) }2 4,97Modul 2 Large Scale Fading Daerah suburbanL50(su)= L50(u) 2{log(f/28)}2 5,4 Daerah rural terbukaL50(rt)= L50(u) 4,78{log(f)}2+ 18,33log(f) 40,94Modul 2 Large Scale FadingKelebihan : mudah digunakan ( langsung dimasukkan pada rumus jadi )Kekurangan: tidak ada parameter eksak yang tegas antara daerah kota,daerah suburban, maupun daerah terbukaLu= 69,55 + 26,16log fC 13,83log hT a(hR) + [44,9 6,55 log hT] log d Lu= 69,55 + 26,16log fC 13,83log hT a(hR) + [44,9 6,55 log hT] log dDimana ,150 s fC s 1500 MHz30 s hT s 200 m , 1 s hr s 10 m1 s d s 20 kma(hR) adalah faktor koreksi antenna mobile yang nilainya adalah sebagaiberikut : Daerah kotaOkumura-Hata Prediction ModelPrediction Model150 s fC s 1500 MHz30 s hT s 200 m , 1 s hr s 10 m1 s d s 20 kma(hR) adalah faktor koreksi antenna mobile yang nilainya adalah sebagaiberikut : Untuk kota kecil dan menengah,a(hR) = (1,1 log fC 0,7 )hR (1,56 log fC 0,8 ) dB, dimana, 1 s hR s 10 m Untuk kota besar,a(hR) = 8,29 (log 1,54hR)2 1,1 dB fC s 300 MHza(hR) = 3,2 (log 11,75hR)2 4,97 dB fC> 300 MHzModul 2 Large Scale Fading Daerah Suburban(((

((

= 4 , 528flog 2 L L 2Cu su Daerah Open Area94 , 40 f log 33 , 18 ) f (log 78 , 4 L L c2c u o + =Okumura-Hata Prediction Model94 , 40 f log 33 , 18 ) f (log 78 , 4 L L c2c u o + =Modul 2 Large Scale FadingMerupakan formula pengembangan rumus Okumura Hata untuk frekuensi PCS ( 2GHz)COST-231 ( PCS Extension Hata Model)M T R T c uC )logd 6,55logh (44,9 ) a(h logh 13,82 logf 33,9 46,3 L + + + =dimana , 1500 MHz s fC s 2000 MHz30 m s hT s 200 m ,1 m s hR s 10 m1 s d s 20 kma(hR) adalah faktor koreksi antena mobile yang nilainya sebagai berikut :Prediction Model Untuk kota kecil dan menengah,a(hR) = (1,1 log fC 0,7 )hR (1,56 log fC 0,8 ) dBdimana, 1 s hR s 10 m Untuk kota besar,a(hR) = 8,29 (log 1,54hR)2 1,1 dB fC s 300 MHza(hR) = 3,2 (log 11,75hR)2 4,97 dB fC > 300 MHzdan,CM =0 dB untuk kota menengah dan kotasuburban3 dB untuk pusat kota metropolitan1500 MHz s fC s 2000 MHz30 m s hT s 200 m ,1 m s hR s 10 m1 s d s 20 kma(hR) adalah faktor koreksi antena mobile yang nilainya sebagai berikut :Modul 2 Large Scale FadingCOST231 Walfish Ikegami ModelCost231 Walfish Ikegami Model digunakan untuk estimasi pathloss untuklingkungan urban untuk range frekuensi seluler 800 hingga 2000 MHz.Wallfisch/Ikegami model terdiri dari 3 komponen : Free Space Loss (Lf) Roof to street diffraction and scatter loss (LRTS) Multiscreen loss (Lms)LC=Lf+ LRTS+ LmsLf; untuk LRTS+ Lms< 0Prediction ModelLC=Lf; untuk LRTS+ Lms< 0 Lf= 32.4 + 20 log10R + 20 log10fcdimana R (km); fc(MHz) LRTS= -16.9 + 10 log10W + 20 log10fc + 20 log10 Ahm + Ludi manaLu=-10 + 0.354| ; 0 < | < 352.5 + 0.075(| - 35) ; 35 < | < 554.0 0.114(| - 55) ; 55 < | < 90Modul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale Fading Lms= Lbsh+ ka+ kdlog10R + kflog10fc- 9log10bdimana Lbsh=-18 + log10(1 + Ahm) ; hb< hr| ; hb> hrka=54 ; hb> hr54 + 0.8hb; d > 500 m hb< hr54 + 0.8 Ahb. R ; 55 < | < 90Catatan : Lshdan kameningkatkan path loss untuk hbyang lebih rendah.COST231 Walfish Ikegami ModelPrediction ModelCatatan : Lshdan kameningkatkan path loss untuk hbyang lebih rendah.kd=18 ; hb> hr18 15 (Ahb/Ahr) ; hb< hrkf=4 + 0.7 (fc/925 - 14 + 1.5 (fc/925 - 1); Untuk kota ukuran sedang dansuburban dengan kerapatan pohoncukup moderat; Pusat kota metropolitanModul 2 Large Scale Fading Model ini valid ; d 5km, hb 50m, micro cell, data basegedung dan jalan yang lengkap Pada prinsipnya model ini terdiri dari 3 elemen yaitu :- Free Space Loss,- Rooftop to Street Diffraction Scatter Loss,- Multi Screen Loss, seperti rumus berikut :L50= Lf+ Lrts+ LmsL50= Lf+ Lrts+ LmsL50= Lf, jika Lrts+ Lms 0Lf= free space loss, Lrts = rooftop to street diffraction & scatterdan Lms= multi screen loss Seperti disinggung di depan Lf dapat dihitung dengan rumusLf= 32,4+ 20log r + 20 log fc (dB)Modul 2 Large Scale Fading Lrtsdapat dihitung dengan rumusLrts= - 16,9 +10log W + 10log fc+ 20log hm+ L0(dB) Variable yang mendukung rumus di atas ditunjukan sepertigambar berikuthbRhbhrhbb whmhmW lebar jalan (m) dan hm= hr hm(m)Lrst= 0 jika hm 0Modul 2 Large Scale FadingbuildingbuildingbuildingbuildingbuildingbuildingL0= -10 +0,354 dB untuk 00 < 350L0= 2,5 + 0,075(-35) dB untuk 350 < 550L0= 4 - 0,114(-55) dB untuk 550 900Modul 2 Large Scale Fading Lmsdapat dihitung dengan rumusLms= Lbsh+ ka+ kdlog r + kflog fc 9logb (dB)Lbsh= -18log(1+ ) hbUntuk hbhb> 0= 0Untuk 0Ka= 54Ka= 54 0,8 hbUntuk hb > 0Untuk r 0,5 dan hb 0Ka= 54 0,8 hbKa= 54 1,6 hbrUntuk r 0,5 dan hb 0Untuk r < 0,5 dan hb 0Kd= 18Untuk hb > 0Kd= 18 -15 (hbhr) hbUntuk 0Kf= -4 +0,7 (f925-1 )Untuk urban dan suburbanKf= -4 +1,5 (f925-1 )Untuk dense urbanModul 2 Large Scale FadingTentukan loss propagasi dengan menggunakan model Hatadan COST 231 antara BTS dan MS pada daerah dense urbanjika diketahui data-data sbb :f = 1887 MHz, hm = 1,5 m , hb = 30 m, r = 3km , hr = 30 m = 900, b = 30 m, W = 15 mModul 2 Large Scale Fadingro= 1mil= 1,6 kmrProPr P P rr ffr roo ono= |\

|.| |\

|.| . . .P P rr n ffr roo o o= |\

|.| |\

|.| + . log . log 10 10Dalam persamaan linear,Dalam persamaan logaritmik (dB),Lees Prediction ModelPrediction ModelP P rr n ffr roo o o= |\

|.| |\

|.| + . log . log 10 10Pr= Daya terima pada jarak r dari transmitter.Pro= Daya terima pada jarak ro= 1 mil daritransmitter.= Slope / kemiringan Path Lossn = Faktor koreksi, digunakan apabila adaperbedaan frekuensi antara kondisi saateksperimen dengan kondisi sebenarnya.o= Faktor koreksi, digunakan apabila adaperbedaan keadaan antara kondisi saateksperimen dengan kondisi sebenarnya.Kondisi saat eksperimen dilakukan,1. Operating Frequency = 900 MHz.2. RBS antenna = 30.48 m3. MS antenna = 3 m4. RF Tx Power = 10 watt5. RBS antenna Gain = 6 dB overdipole l/2.6. MS antenna Gain = 0 dB overdipole l/2.Modul 2 Large Scale Fading L0and are obtained from tablewherehb in mPT in WGb = BS antenna gain in scalarhm in mfc = carrier frequency in MHzf0 = In an 900 MHz frequency referencen = 2 - 3Lee Models0 0 log F d L LLee + + = 5 4 3 2 1 0 F F F F F F =215 . 30 |.|

\|= bhFEnvironment L0 [dB] Free Space 91.3 20Open (Rural) 91.3 43.5Suburban 104.0 38Urban:Tokyo 128.0 30Philadelpia 112.8 36.8Newark 106.3 43.1Modul 2 Large Scale Fading L0and are obtained from tablewherehb in mPT in WGb = BS antenna gain in scalarhm in mfc = carrier frequency in MHzf0 = In an 900 MHz frequency referencen = 2 - 3215 . 30 |.|

\|= bhF102 TPF =43 bGF =234 |.|

\|= mhFncffF ||.|

\|=05Environment L0 [dB] Free Space 91.3 20Open (Rural) 91.3 43.5Suburban 104.0 38Urban:Tokyo 128.0 30Philadelpia 112.8 36.8Newark 106.3 43.1Proand didapat dari data hasil percobaanin free space,Pro= 10-4.5mWattsg = 2in an open area,Pro= 10-4.9mWattsg = 4.35in urban area (Philadelphia),Pro= 10-7mWattsg = 3.68in urban area (Tokyo),Pro= 10-8.4mWattsg = 3.05ao= faktor koreksio=1 . 2 . 3 . 4 . 521(m) 48 . 30 (m) riil station base antena tinggi||.|

\|= v(m) 3 (m) riil unit mobile antenna tinggi2 ||.|

\|= Lees Prediction Modelin an open area,Pro= 10-4.9mWattsg = 4.35in sub urban area,Pro= 10-6.17mWattsg = 3.84in urban area (Tokyo),Pro= 10-8.4mWattsg = 3.05v(m) 3 (m) riil unit mobile antenna tinggi2 ||.|

\|= ||.|

\|=(watts) 10 (watts) riil pemancar daya3|.|

\|=4 2 dipole antena tdh riil station base antena gain4 |.|

\|=1 2 dipole antena thd. riil unit mobile antena gain54 Modul 2 Large Scale FadingLees Prediction Modeln diperoleh dari percobaan / empirisdec / dB 30 n dec / dB 20 s sHarga n diperoleh dari hasil percobaan yangdilakukan oleh Okumura dan YoungBerdasarkan eksperimen oleh Okumuran=30 dB/dec untuk Urban Area.Correction factor to determine vin a2v = 2,for new mobile-unit antenna heigh > 10 mv = 1,for new mobile-unit antenna heigh < 3 mBerdasarkan eksperimen oleh Okumuran=30 dB/dec untuk Urban Area.Berdasarkan eksperimen oleh Youngn=20 dB/dec untuk Sub.Urban Areaatau Open Arean hanya berlaku untuk frekuensi operasi30 sd. 2,000 MHzv = 1,for new mobile-unit antenna heigh < 3 mModul 2 Large Scale Fading3Jarak dalam mil2 4 5 6 7 8 9 10 1-110-100-90-80-70-60-50-120Signal strength in dBm1222324252627282Signal strength in dB(mikroVolt)New York City ( Po = - 77 dBm, = 48 dB/dec )Tokyo, Japan ( Po= - 84 dBm, = 30.5 dB/dec )Philadelphia ( Po = - 70 dBm, = 36.8 dB/dec )Newark ( Po = - 64 dBm, = 43.1 dB/dec )Suburban ( Po = - 61.7 dBm, = 38.4 dB/dec )Open Area ( Po = - 49 dBm, = 43.5 dB/dec )Open Area ( Po = - 45 dBm, = 20 dB/dec )Lees Prediction Model3Jarak dalam mil2 4 5 6 7 8 9 10 1-110-100-90-80-70-60-50-120Signal strength in dBm1222324252627282Signal strength in dB(mikroVolt)New York City ( Po = - 77 dBm, = 48 dB/dec )Tokyo, Japan ( Po= - 84 dBm, = 30.5 dB/dec )Philadelphia ( Po = - 70 dBm, = 36.8 dB/dec )Newark ( Po = - 64 dBm, = 43.1 dB/dec )Suburban ( Po = - 61.7 dBm, = 38.4 dB/dec )Open Area ( Po = - 49 dBm, = 43.5 dB/dec )Open Area ( Po = - 45 dBm, = 20 dB/dec )Modul 2 Large Scale Fadingro= 1mil= 1,6 kmr1ProPrr2area 1area 2rr1r2rarea 1 area 21.6 kmLees Pathloss Formula Untuk Berbagai Jenis KondisiLingkunganr1r2r 1.6 kmono 1 o1ro r .ff.rr.rr. P P 2 1 ||.|

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\|=o=1 . 2 . 3 . 4 .5ono 1 N 12o1ro r .ff.r r. ... .rr.rr. P P N 2 1 ||.|

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\|=persamaanumum,Modul 2 Large Scale FadinguMOBILEBuildingIncidentWave u = incident angle relative to streetBuildingBuildingBuildingRDiagram ParameterwobMobileRhb Ahbhr AhmhmCell siteGROUNDModul 2 Large Scale Fading L [dB]=L (d0)+10 log (d/d0) from table 3.2 (Rappa, pp 104)Log Distance Path Loss ModelEnvironment Pathloss ExponentFree Space 2Urban 2.7 - 3.5Shadowed Urban 3.0 - 5.0in building LOS 1.6 - 1.8in building Obstructed 4.0 - 6.0in factories Obstructed 2.0 - 3.0Modul 2 Large Scale FadingEnvironment Pathloss ExponentFree Space 2Urban 2.7 - 3.5Shadowed Urban 3.0 - 5.0in building LOS 1.6 - 1.8in building Obstructed 4.0 - 6.0in factories Obstructed 2.0 - 3.0 L [dB]=L (d0)+10 log (d/d0) + X Shadowing effect + fading margin + availability (Rappa, pp 104)Log-normal ShadowingModul 2 Large Scale Fading L [dB]=L (d0)+10 log (d/d0) + X Shadowing effect + fading margin + availability (Rappa, pp 104)Modul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingModul 2 Large Scale FadingThe measurement method with Regression Methods Select multiple locationsat distances d1and takethe measurement ofpath loss Repeat for thedistance d2and d3, etc. Plot of themean pathloss asa function of distanceCell site(Tx)d1d2d3Modul 2 Large Scale Fading Select multiple locationsat distances d1and takethe measurement ofpath loss Repeat for thedistance d2and d3, etc. Plot of themean pathloss asa function of distanceCell site(Tx)Getting Mean and Standard Deviation Measurement isusually done for some typesof areas: Urban, suburban, andopen areas Measurements at constant radius from the BTS to producedifferent pathloss With the linear regression method,we can obtain the meanpathloss trend and standarddeviation around the average value Example for urban: path loss Slope = 33.2 dB / decade and Std dev. = 7 dBPath loss [dB]urbanxxxx xx x xx xx xx xx xo o oo o oo oo oo oo ooo o798575Modul 2 Large Scale Fading Measurement isusually done for some typesof areas: Urban, suburban, andopen areas Measurements at constant radius from the BTS to producedifferent pathloss With the linear regression method,we can obtain the meanpathloss trend and standarddeviation around the average value Example for urban: path loss Slope = 33.2 dB / decade and Std dev. = 7 dB Distance d [km]Path loss [dB]suburbanopenxxxx xx x xx xx xx xx xo o oo o oo oo oo oo ooo o# ## ## ##3 4 675

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