1. By Project & Technical Support Department Mar 2003UTSI CONFIDENTIAL

2. Base Station Antenna Mobile Radio environment (Top View) Propagation Path Loss region Multipath Fading RegionThree Basic mechanism that effects signalpropagation of mobile communicationSystem: Reflection Diffraction ScatteringUTSI CONFIDENTIAL 3. RF PropagationIn Mobile communication environment the propagation is influenced by the various factors such as: Reflection Occurs when a propagating electromagnetic wave strikes a smooth surfsce with a very large dimensions compared to the RF signal wavelengthExample- Ground reflected waves Diffraction Occurs when the radio path between the transmitter and receiver is obstructed by adense body with the large dimensions compared to the wavelength. Accounts for the RF energy traveling from transmitter to receiver without using line of sight path between the two.Example- Obstruction hills, irregular terrain and sharp edged building corners Scattering Occurs when a radio wave impinges on either large rough surface or any surface whose dimensions are on the order of the signals wavelength or less Cause reflected energy spread out in all directions Example - urban environment - objects like lamp posts, street signs, foliageUTSI CONFIDENTIAL 4. Multipath Fading The presence of reflecting objects and scatterers in the channel creates a constantlychanging environment that dissipates the signal energy in amplitude, phase andtime. This results in fluctuations in signal strength, thereby inducing fading,distortion or both Speed of Mobile The relative motion between the base station and the mobile results in randomfrequency modulation due to different Doppler shifts on each of the multipathcomponents. Speed of the surrounding Objects The object that move at a greater rate that the mobile would induce a time varyingDoppler shift on multipath components and thus results in fading and distortion.UTSI CONFIDENTIAL 5. In mobile environment, the rate of change of RF signal over the distance is not necessarly to follow either R-2 or R-4.Jian De - Com m ercial CS Height is 21 mtrs. 80 70 60LOS outdoor 50 No LOS outdoor RSSi (dBuV)Indoor 40CF-LOS outdoor 30 CF-No LOS outdoor dBuV= -22.5log(d) + 106.68 -bef ore breal point, Stdev.CF-Indoor dBuV= -88.3log(d) + 243.568 -af ter breal point, Stdev. 20 dBuV= -59.5log(d) + 171.4, Stdev. 4.06dB 10 dBuV= -6log(d) + 58.207 -before breal point, Stdev. dBuV= -77.5log(d) + 204.437 -af ter breal point, Stdev. 010 100 1000Distance (mtrs)UTSI CONFIDENTIAL 6. In Mobile environment, the RF signal propagation is statistically distributed unlike in Free Space environment doe to the large scale and small scale fading and distortion. The RSSI over the distance is normally distributed with standard Deviation 8 dB. The Solid line represents the mean curve of the RSSI signal level at a given distance from the Base Station. I.e. The Probability is 50% Any RF Propagation equation represents mean curve RSSI is normally distributed IS RS DistanceUTSI CONFIDENTIAL 7. Three important Statistical Distributions 1 Normal Distribution 2 Binomial Distribution 3 Poisson DistributionUTSI CONFIDENTIAL 8. Statistics- Basics 1 nMean( ) Xn n 1 1 nVariance ( ) 2 (xn )2 n 1 1 1 nStandard Deviation ( ) (xn )2 n 1 1UTSI CONFIDENTIAL 9. Normal Distribution Central Limit Theorem The frequency distribution of a large random sample size n is Normal, a bellshaped curve The sampling mean of a large random sample size of n is normallydistributed., a bell shaped curve. Normal DistributionUTSI CONFIDENTIAL 10. The Standard Deviation determines the shape of the curveNormal Distribution Normal Distribution =0.5 ProbabilityProbability=2 - + f(X=x) - f(X=x) + Normal Distribution=1Probability- + f(X=x)UTSI CONFIDENTIAL 11. Area under the curve is 1 and the below or above mean is 0.5 Normal Distribution Normal DistributionNormal Curve N(, )ProbabilityProbability Probability = 0.5 - f(X=x) +- f(X=x) + Normal Distribution = Mean = Std. Dev ProbabilityProbability = 1 - +UTSI CONFIDENTIALf(X=x) 12. 68%-95%-99.7% Rule Normal Distribution Normal DistributionProbability = 0.68Probability = 0.95ProbabilityProbability(CDF)(CDF)- - 1 f(X=x) +1+- -2 f(X=x) +2 + Normal DistributionProbability = 0.997Probability(CDF)- -3 f(X=x) +3 +UTSI CONFIDENTIAL 13. Standard Normal Curve Standard Deviation ( ) = 1Mean () = 0Standard Normal Distribution =1Probability- -Z0+Z +f(X=x)UTSI CONFIDENTIAL 14. How to Convert a Normal Curve to Standard Normal Curve x Standard Transformation is z= Standard Normal Distribution Normal Distribution =1 ProbabilityProbability- + -x +x-z0 f(X=x) +z-f(X=x)+UTSI CONFIDENTIAL 15. Table of z0.00 0.01 0.02 0.030.04 0.05 0.06 0.07 0.08 0.09-0.3 0.3821 0.3783 0.3745 0.37070.3669 0.3632 0.3594 0.3557 0.3520 0.3483-0.2 0.4207 0.4168 0.4129 0.40900.4052 0.4013 0.3974 0.3936 0.3897 0.3859-0.1 0.4602 0.4562 0.4522 0.44830.4443 0.4404 0.4364 0.4325 0.4286 0.4247-0.0 0.5000 0.4960 0.4920 0.48800.4840 0.4801 0.4761 0.4721 0.4681 0.46410.00.5000 0.5040 0.5080 0.51200.5160 0.5199 0.5239 0.5279 0.5319 0.53590.10.5398 0.5438 0.5478 0.55170.5557 0.5596 0.5636 0.5675 0.5714 0.57530.20.5793 0.5832 0.5871 0.59100.5948 0.5987 0.6026 0.6064 0.6103 0.61410.30.6179 0.6217 0.6255 0.62930.6331 0.6368 0.6406 0.6443 0.6480 0.6517UTSI CONFIDENTIAL 16. Standard Normal Distribution CalculatorUTSI CONFIDENTIAL 17. Confidence Level, Confidence Interval & Margin of Error The area under the curve( i.e. Probability / CDF) C is C% Confidence Level The distance between boundaries at equal distances both sides from mean C%Confidence Interval The distance between mean and one side of the boundary is C% Margin of errorNormal DistributionStandard NormalCurve N( =0, =1)Probability1CProbability = C1C == 22--z* f(X=x) +z*+UTSI CONFIDENTIAL 18. In mobile environment, the rate of change of RF signal over the distance is not necessarly to follow either R-2 or R-4.Jian De - Com m ercial CS Height is 21 mtrs. 80 70 60LOS outdoor 50 No LOS outdoor RSSi (dBuV)Indoor 40CF-LOS outdoor 30 CF-No LOS outdoor dBuV= -22.5log(d) + 106.68 -bef ore breal point, Stdev.CF-Indoor dBuV= -88.3log(d) + 243.568 -af ter breal point, Stdev. 20 dBuV= -59.5log(d) + 171.4, Stdev. 4.06dB 10 dBuV= -6log(d) + 58.207 -before breal point, Stdev. dBuV= -77.5log(d) + 204.437 -af ter breal point, Stdev. 010 100 1000Distance (mtrs)UTSI CONFIDENTIAL 19. In Mobile environment, the RF signal propagation is statistically distributed unlike in Free Space environment doe to the large scale and small scale fading and distortion. The RSSI over the distance is normally distributed with standard Deviation 8 dB. The Solid line represents the mean curve of the RSSI signal level at a given distance from the Base Station. I.e. The Probability is 50% Any RF Propagation equation represents mean curve RSSI is normally distributed IS RS DistanceUTSI CONFIDENTIAL 20. Example If the mean curve tells you that the RSSI at 100 mtrs from the base station is 40 dBuV, at most (equal or less than) what should be RSSI level for 95% probability when The signal propagation has the standard deviation of 8dB?UTSI CONFIDENTIAL 21. x z=Normal Distribution If the mean curve tells you that the RSSI at 100 mtrs from the base station is 40 dBuV, at most (equal or less than) what should be RSSI levelProbability for 95% probability when The signal propagation has the standard deviation of Probability = C 8dB? =40; =8 We have to find out x value from the above equation.From the table, for the probability=0.95 -+z+ f(X=x) (95%) , Normal Distribution z = +1.645 When we substitute z, , values in above equation,Standard NormalProbability Curve N( =0, =1) x= 53.2 dBuV Probability = 0.95 The RSSI level of 53.2dBuV or above will have the probability of 95% OR, 95% of the time the RSSI level at thatpoint is 53.2 dBuV or more- f(X=x)+1.645 +UTSI CONFIDENTIAL 22. ExampleThe RF propagation in a typical urban area is characterized by the relation,RSSI(in dBuV) =171-59.5Log(d inMtrs.) with the standard deviation of 8dB. Thethreshold signal required for the PSs successful operation is 32 dBuV.What is the radial distance covered by the base station?What should be the radial distance at which it is 90% coverage confidence(boundary coverage confidence)?UTSI CONFIDENTIAL 23. The RF propagation in a typical urban area is characterized by the relation RSSI(in dBuV) =171-59.5Log(d inMtrs.) with the standard deviation of 8dB. The threshold signal required for the PSs successful operation is 32 dBuV. What is the radial distance covered by the base station? What should be the radial distance at which it is 90% coverage confidence (boundary coverage confidence)? The relation RSSI = 171-59.5 Log(d) is amean curve for the RF propagation at aNormal Distributiongiven urban area. From the relation we can find out the RSSIlevel (in dBuV) for various distances d.Probability For the RSSI level of 32 dBuV, using the Probability = 0.5above equation, the radial distance coveredby the base station is , 32=171-59.5Log(d),d=216 mtrs.368 m216 Mtrs)-32f(X=x) + Since the relation is the mean curve, theboundary coverage confidence at 216mradius is 50% (I.e. RSSI 32dBuV and above)UTSI CONFIDENTIAL 24. Now, for the 90% coverage confidence, the probabilityfor RSSI is equal to 32 dBuV and above should be 90%. Normal DistributionWe use the value 32dBuV since it is threshold level inour problem. So, our strategy is to find out the value for which Standard Normalthe probability for RSSI is equal to and above 32 dBuV Curve N( =0, Probabilityis 90%. Finally use this value in the equation,=1)Probability = 0.90RSSI=171-59.5Log(d) to find out the radial distance d.This is the coverage for 90% confidence. =0.10 If the probability for RSSI 32 is 90%, then Probabilityfor RSSI 32 is 10%.-Z=-1.282 f(X=x)+ Find out z from the table for the probability = 0.10.From the Table, z=-1.282 Normal Distribution In our problem x=32 dBuV, =8 dB, z=-1.282x Substitute the above values in z= to get . Probability Normal Curve N( =42, =8)Probability = 0.90 = 42dBuV . This is the RSSI value at which thecoverage confidence is 90% =0.10 From the the equation RSSI=171-59.5Log(d), d=147m 147m radius from the base station would provide -32dBuV =42dBuV f(X=x)+UTSI CONFIDENTIAL 25. Cell Edge Confidence Contours for RSSI=171-59.5Log(d) & Std. Dev=8dB216m Radius 50% cell edge confidence 157m Radius 85% cell edge confidence 147m Radius 90% cell edge confidence 130m Radius 95% cell edge confidenceBase StationUTSI CONFIDENTIAL 26. Cell Boundary (or Edge) confidence Vs Cell Area Confidence In our last example we have seen how to calculate boundary coverage confidence (I.e.percentage of time the signal is to exceed the threshold at the boundary). It is possible to relate and compute the percentage of area covered within theboundary. i.e. the percentage of area with a received signal that is equal or greaterthat threshold RSSI level. It is computed from the below relations:Cell Edge Confidence Cell Area Confidence from Cell Edge Confidence 1 1 x y 1 2xy 1 -x 2 F u = 1 erf ( x) + e y2 1 erf Confidence Edge = 1 - e 2 dx 2 y 2 10nlog ( r ) 10 n log10e n = Path loss exponent y =r = Normalized cell radius(on the cell boundary, r = 1) 2 x = = Log normal shadow standard deviation 2 2 x erf ( x) = e t dt2 1 p 0 -x 2 2 log( 2r ) dx = Outage probability (cell edge)e = Log normal shadow margin for a given x o 10n (seelog normal shadow margin section for equation) n = Path loss exponentIt is the percentage of time when a receiver experiencesshadowed performance during shadowing. = Log normal shadow standard deviation in dBUTSI CONFIDENTIAL 27. Comparison of Cell Edge - Cell Area Confidence (R^4 Propagation, 8 dB Sigma)110%100% Confidence Level (%)90%Cell Edge80% Cell Area70%60%50% 0.00 1.012.033.08 4.205.406.73 8.29 10.25 13.1624.72 Log Norm al Fade Margin (dB)UTSI CONFIDENTIAL 28. Micro Cell RF Propagation Model The commonly used models for cellular technology , especially for GSM environment are, Okumara, Lee and Hata models. These models are derived based on the emprical data collected through extensive experiments at various citiessuch as New York, Tokyo, etc However these models are more applicable for the range one Km and above. I.e for macro cellular environment. PHS technology is based on micro cell concept. The Cell radius is 200-300 Mtrs. Akayama and Kaji first published a RF model for such micro cells. UTStarcom developed a model based on its extensive experiments at various cities in China and based on the resulted experimental data. Combining the experimental data and the statistical techniques, as discussed so far, a software tool is developed to predict the RF coverage and thus to design the RF network.UTSI CONFIDENTIAL 29. Composite 500mW CS Micro-Cell Propagation Measurement LO S r eet - S deS ti LO U ban- R S res I ndoor N LO U ban- Ro S res I ndoorLO O d Tow A l ey S ln l no LO S r eet - S deS t ino LO G t I ndoorS vm O d Tow I ndoorl n80. 070. 060. 0 uV50. 0 dB40. 030. 020. 010. 0101001000 D st anceiUTSI CONFIDENTIAL 30. RF Design Tool - MicroWizard IntroductionMicroWizard is a RF network design tool, with a laconic interface, a simpleoperation and powerful function. We can availably design network with givenenvironments through the tool. We can systematically decide the number of CS per a coverage area Calculate the commonly recognized coverage radius for the 500mW CSWhen we adjust various design parameters of an RF network, we willconcretely know how does each factor impact the performance of theentire network We can design new network more accurately and effectively MicroWizard can run in WIN98/WIN2000 operating system, with graphicinterface and simple operation.UTSI CONFIDENTIAL 31. Parameters of the MicroWizardUTSI CONFIDENTIAL 32. Meaning of Some Parameter TypeDefinition Dense Urban A complicated area mixed with 8-15 layers building and 15-20 layers intensive buildings, with 4 main streets and 2 small roads and few or no more trees Urban A complicated area mixed with 4-6 layers and 6-15 layers commercial /apartment houses/marketplace, with 4 main streets and 2 small roads and few or no more trees. Relation to dense urban ,the building is not so high and intensive. SuburbanGenerally less than 4 layers houses along the expressway/main road. The houses and hotels are arranged with 1-2 alignments at the outside town, there is few and middle quantity vegetation highway smooth road Rural There is self-governed small houses and independent/field.UTSI CONFIDENTIAL 33. Meaning of Some ParametersTypeDefinitionPlane Earth This is the smooth and flat ground with a lot of spacing suchas wide roads, parks in between the builit up area of 6-8story buildings.Rolling hills Hilly terrain with frequent ups and downs.Rugged terrainThe area Uneven, rocky and rough trrainSignificant The area with lake or riverlake/riverCrowded low-lvl The area with 1or 2 story houses with very less spacing orhousing no spacing between the houses and a very very narrowstreets of 1-1.5 metres.Lossy ground/soil The area with Muddy and watery soilsCrowded hi-rise The area with high rised buildings of more than10 storyspacing buildings separated by wide roadsUTSI CONFIDENTIAL 34. Meaning of Some Parameters Type Definition None This is used mainly when out door coverage is to be providedSuch as on high ways, cover the lake , river etc, 13dB thin wall The buildings with wall size of 4-6 thickness-especially old typeindependent houses, apartments, small shops,etc Thin wall w./ Roof Old type houses with roof bricks and no floors with walls of 4 Leakagethickness where the CS is place in such a way that the RF signalcan reach the indoor through the roofs Medium wallThe buildings with 6-9 thickness wall. Especially commercialbuildings, Private and Govt. office buildings,shopping mallsapartment houses etc, ThickThe buildings with 9 and above thickness of wall. building/wall Rain fades Rainy places Dense Vegetation The place with dense trees and plantations.UTSI CONFIDENTIAL