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RF COURSE CONTENTS
CDMA Drive Test in 5 important parameters worth to see
1)TXPOWER 2)RXPOWER 3)Ec/Io 4)TXADJ 5)FER. 1.EcIo EcIo reflects the handset in the current received pilot signal level. This is an integrated pilot signal. Why, because mobile phones are a multi-channel soft switching, which translates into mobile phones often lies in more than one pilot overlapping coverage area, the level of the phone, EcIo reflects the phone at this point that a multi-channel pilot signal level of the overall coverage. We know that the Ec is a mobile phone available pilot signal strength, and Io is the mobile phone receives all the strength of the signal. Therefore, EcIo reflects the available signal strength in occupies all signals. The higher the value, the greater the proportion of a useful signal, on the other hand also reversed. At some point EcIo big, there are two possibilities. First, the Ec is very large, dominant level here, Ec, Io is very small, that is to say here is from another base station's messy little pilot signal, EcIo also larger. In the latter case is weak, because the Ec small, Io is also small, so small, so RSSI also there may be dropped. At some point EcIo also small, there are two possible, first, the Ec is also small small RSSI, this is the weak coverage area. The Ec is not small, RSSI, this illustrates the Io is the overall intensity of the signal is not bad. This situation is often a BSC switch data configuration, no nearby strong pilot signal into the adjacent community table, so the phone doesn't recognize the strong pilot signal in the vicinity as a jamming signal processing. On the road, in the case of a typical phenomenon is the phone in a move to maintain certain RSSI, EcIo level, rapid rise to FER and eventually dropped. 2 TXPOWER TXPOWER is the phone's transmitter power. We know that power control is guaranteed call quality and address the CDMA community interference tolerance and one of the key means of mobile phone from the base station near, uplink quality good, the mobile phone transmitting power is smaller, because at the base station is able to guarantee the reception of the signal to launch mobile phone and fer also small and mobile phones transmitting power is smaller to other mobile phones in the community is also a small interference. So mobile phones transmit power level, reflecting the handset's current uplink loss and interference. Uplink loss of large, or there is serious interference with the phone's transmitter power will be greatly missed mobile phone transmitting power is smaller. Roadtest, in normal circumstances, the more closer to the base station or Repeater, the mobile phone transmitting power is reduced, away from the base station and Repeater, the mobile phone transmitting power increases. If the base station and Repeater nearby mobile phone transmitting power, obviously it is not normal. Perhaps there is interference, the uplink can be a base station and Repeater itself. Such as community antenna wrong receive carrier frequency amplifier circuit problems, etc. If the Repeater nearby, cell phone transmitter power, it may be a Repeater malfunctions, uplink gain set too small, and so on.Above you can

see, the road of TXPOWER level reflects the base station coverage area of reverse link quality and uplink interference levels. 3RXPOWER RXPOWER is a mobile phone to receive power. In CDMA, according to my personal understanding, there are three parameters is very close by, you can almost equivalent to the use of parameters. Namely RXPOWER, RSSI, Io. RXPOWER is a mobile phone to receive power, Io is mobile phones currently receives all signal strength, RSSI is receives downlink band of total power, as currently I have access to information, the title explains, but understanding is very similar, is the phone receives a total of signal strength. RXPOWER and reflects the current signal receiving phone, RXPOWER small area, the weak positive fall within the coverage area, RXPOWER places belong to the covered area. But the high places, RXPOWER and does not necessarily signal quality is good, because there may be no signal, leading to frequency, or too many strong pilot, pilot frequency pollution. Therefore, the analysis of RXPOWER to EcIo to analysis.Above you can see, RXPOWER and simply reflects the drive test signal coverage area, rather than the quality of the signal coverage. 4TXADJ TXADJ reflects the up and down-link a balance. Note that this value is calculated from the measurement, instead. 800M CDMA system is Tx_adjust = 73dB + Tx_power + Rx_power, 1900M CDMA is Tx_adjust = 76dB + Tx_power + Rx_power. TXADJ reflects the current location of the mobile uplink and downlink of a more mass. We know that under normal circumstances, the cell phone away from the base station close to the phone's transmitter power will decrease, and received power will become larger and far away from the cell phone, mobile phone base station transmitter power will increase while receiving power gets smaller. Normally, the transmitter power and receiver power plus a constant fixed values, the result should be a small interval (for example,-10 to + 10). If TXADJ great, it means that the phone's transmitter power, receive the power, then it is obvious that mobile current downlink of good quality (receiving power), and the poor quality of the uplink (transmitter power), this time forward link is better than a reverse link. On the contrary, TXADJ is very small, explains this reverse link well to the forward link. We know that the base station coverage depends on the reverse link loss level. Therefore, in General, we require the following TXADJ in 0. But greater than 10, the reverse link forward link than are poor, the situation is not ideal. For TXADJ, nor can they be said to be as small as possible. But in the actual drive test, we generally encounter, often TXADJ too high, forward link, reverse link. 5 FER FER is a forward-fer. Forward fer with EcIo also is a comprehensive quality of forward link. Because when the phone is in the multi-channel soft switching, fer actually multi-channel forward an integrated signal quality. FER, description of the mobile phone of the forward link better, received signal is good, this time EcIo also should be better. The larger the Description cell phone FER the received signal strength is poor, EcIo should also at this time. FER is large, it may also be due to a neighboring community switch parameter configuration error. If you switch between adjacent community with leakage, single and mobile to mobile, adjacent to the pilot was not recognized, and the pilot does not recognize, it will become interference signal, resulting in increased FER. In reality, often manifested in mobile, mobile phones, FER a rapid rise in sharp decline, EcIo, and finally dropped.Above that is closely followed by EcIo FER. FER reflects the call quality is good or bad, reflects the RoadTest

regional coverage quality level, rather than the signal coverage strength level. In some areas although belonging to the weak signal coverage area, but relatively clean (messy signals, noise), as well as be good FER. Note the above parameters, EcIo, RXPOWER is the phone in standby or call have parameters, TXPOWER, TXADJ, FER is only a phone call and from the only parameter. The above five parameters, together, to analysis of drive test region to cover the intensity level, the former to override the quality level, as well as the reverse link loss level, and so on, is the analysis of drive test is the most important parameters. In-depth understanding of the five parameters, combined with the overall situation for drive testing specific analysis, is engaged in network optimization staff in one of the basic conditions.

CDMA Drive Test- 5 Important Parameters worth to see 1)TXPOWER 2)RXPOWER 3)Ec/Io 4)TXADJ 5)FER. For more detail About Click Here 1.EcIo EcIo reflects the handset in the current received pilot signal level. This is an integrated pilot signal. Why, because mobile phones are a multi-channel soft switching, whichtranslates into mobile phones often lies in more than one pilot overlapping coverage area, the level of the phone, EcIo reflects the phone at this point that a multi-channel pilotsignal level of the overall coverage. 2 TXPOWER TXPOWER is the phone's transmitter power. We know that power control is guaranteed call quality and address the CDMA community interference tolerance and one of the key means of mobile phone from the base station near, uplink quality good, the mobile phone transmitting power is smaller, because at the base station is able to guarantee the reception of the signal to launch mobile phone and fer also small and mobile phones transmitting power is smaller to other mobile phones in the community is also a small interference. 3RXPOWER RXPOWER is a mobile phone to receive power. In CDMA, according to my personal understanding, there are three parameters is very close by, you can almost equivalent to the use of parameters.

Module-A
Introduction to Radio waves......................................................................................................... 1 Cell site, Introduction & classification of cell site……………………………………………………………………… 1 Different types of Telecom Towers & Shelters ………………………………………………………………………… 6 RF Cables & RF Connectors………………………………………………………………………………………………………. 9 Introduction to Antenna, Antenna……………………………………………………………… Properties of Antenna, Antenna Gain………………………………………………………… Antenna Tilt, Mechanical & Electrical Tilt……………………………………………………

Module A: Fundamental of Radio Frequency
The term "RF waves" typically refers to radio frequency waves, a form of electromagnetic energy invisible to the human eye. Radio frequency communication is virtually omnipresent in the modern world, used for everything from automobile radios to computers. Radio frequency (RF) is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals. RF waves travel at the speed of light, and are also emitted by natural sources including stars. Radio frequency (RF) energy has been used in medical treatments for over 75 years, generally for minimally invasive surgeries, using radiofrequency ablation and cryoablation, including the treatment of sleep apnea. Magnetic resonance imaging (MRI) uses radio frequency waves to generate images of the human body.
CELL: A cell is the basic geographic unit of a cellular system and is defined as by one BS antenna system. the area of radio coverage given

Classification of cells in GSM Network: Large Cells: Large cells are employed in 1. Remote areas. 2. Coastal regions. 3. Areas with few subscribers. 4. Large areas which need to be covered with the minimum number of cell sites

SMALL CELLS or MICRO CELLS:     Urban areas. Low transmission power required. High number of MS’s. However, micro cells are cells where the antenna height is under the average roof top level and they are typically used in urban areas

Pico Cells: The Pico cells are small cells whose diameter is a few dozen meters and are mainly used indoors.

Umbrella Cells: Umbrella cells are used to cover shadow regions of smaller cells and fill in gaps of coverage between those cells. These cells are usually built on high ways to cover the uncovered region. A Cluster is a group of cells. No channels are reused within a cluster. If a cluster has 3 cells, it is called 3 cell cluster, if a cluster has 4 cells, it is called 4 cell cluster, and if it is 7 cells, it is called 7 cell cluster.

Telecommunication Towers:

Telecommunication towers are used for communication purposes among people. All the wireless communication, mobile networking, radio broadcasting and television antennas are connected via these towers. A full telecommunication tower is a whole set of mechanical structures and electronic signal processing unit which is used to connect people via telecommunications. All the telephone lines and mobile phone services are connected through these towers. These towers are also used for radar system and other armed forces purposes. Different heights of towers are used in different places and purposes. They can vary from 15 to 60 meters and some time more if required. For example in the land areas towers are higher in hill area so 15 to 30 meters high towers can be used but in land areas they are 30 to 60 meters in height. There are different types of the telecommunication towers which are used i.e. monopole, self supporting and guyed etc. The most used are the self supporting towers in the field of telecommunication, which is the specialization of final project and thesis as well. Based on structural action.
Towers are classified into three major groups based on the structural action. They are: • • • Self supporting towers Guyed towers Monopole.

Self supporting towers.

The towers that are supported on ground or on buildings are called as self-supporting towers. Though the weight of these towers is more they require less base area and are suitable in many situations. Most of the TV, MW, Power transmission, and flood light towers are self-supporting towers. Guyed towers. Guyed towers provide height at a much lower material cost than self-supporting towers due to the efficient use of high-strength steel in the guys. Guyed towers are normally guyed in three directions over an anchor radius of typically 2/3 of the tower height and have a triangular lattice section for the central mast. Tubular masts are also used, especially where icing is very heavy and lattice sections would ice up fully. These towers are much lighter than self- Design of Steel Structures. Whenever large open space is available, guyed towers can be provided. There are other restrictions to mount dish antennae on these towers and require large anchor blocks to hold the ropes. Monopole It is single self-supporting pole, and is generally placed over roofs of high raised buildings, when number of antennae required is less or height of tower required is less than 9m. Based on cross section of tower Towers can be classified, based on their cross section, into square, rectangular, triangular, delta, hexagonal and polygonal towers. Open steel lattice towers make the most efficient use of material and enable the construction of extremely light-weight and stiff structures by offering less exposed area to wind loads. Most of the power transmission, telecommunication and broadcasting towers are lattice towers. Triangular Lattice Towers have less weight but offer less stiffness in torsion. With the increase in number of faces, it is observed that weight of tower increases. The increase is 10% and 20% for square and hexagonal

cross sections respectively. If the supporting action of adjacent beams is considered, the expenditure incurred for hexagonal towers is somewhat less Based on the type of material sections Based on the sections used for fabrication, towers are classified into angular and hybrid towers (with tubular and angle bracings). Lattice towers are usually made of bolted angles. Tubular legs and bracings can be economic, especially when the stresses are low enough to allow relatively simple connections. Towers with tubular members may be less than half the weight of angle towers because of the reduced wind load on circular sections. However the extra cost of the tube

and the more complicated connection details can exceed the saving of steel weight and foundations. Based on the placement of tower Based on this placement, Communication towers are classified as follows: Green Field Tower Roof Top Tower Erection Erected on natural ground with suitable foundation Erected on existing building with raised columns and tie beams. Height 30 – 200 m 9 – 30 usual Location Rural Areas Urban Areas Economy Less More Based on the number of segments: The towers are classified based on the number of segments as three slope tower; two slope tower; Single slope tower; Straight tower.

Telecom Shelter: Shelter or cabinet” means a cabinet or building used by telecommunication providers to
house equipment at a facility.

RF Cable & RF Connectors:

 ANTENNA:  An antenna is a specialized transducer that converts radio-frequency (RF) fields into alternating current (AC) or vice-versa. There are two basic types: the receiving antenna, which intercepts RF energy and delivers AC to electronic equipment, and the transmitting antenna, which is fed with AC from electronic equipment and generates an RF field.



Directional antenna – Antenna having a preference for a particular direction and radiating (receiving) a signal more efficiently in (from) this direction than in other directions.





Isotropic antenna – Antenna transmitting (receiving) equal radiation in (from) all directions. Isotropic antenna is a idealized device that does not exist in reality. It is usually taken as a reference when measuring directivity of actual antennas. Omni directional antenna: Antenna transmitting (receiving) equal radiation in (from) all directions. A typical example is a whip antenna. Whip antenna's radiation power is distributed equally in all directions in a plane perpendicular to the whip.

The Yagi antenna:   The Yagi antenna or more correctly, the Yagi - Uda antenna was developed by Japanese scientists in the 1930's. It consists of a half wave dipole, a rear "reflector" and may or may not have one or more forward "directors". These are collectively referred to as the "elements of Yagi Antenna”.

Parabolic antenna:  The parabolic antenna is a high-gain reflector antenna used for radio, television and data communications, and also for radio location (RADAR), on the UHF and SHF parts of the electromagnetic spectrum. The relatively short wavelength of electromagnetic (radio) energy at these frequencies allows reasonably sized reflectors to exhibit the very desirable highly directional response for both receiving and transmitting.



RADITION PATTERN:  “A radiation pattern is a plot of electric field intensity, at a fixed distance, as a function of direction from the antenna or antenna array. Although radiation patterns [can be] determined mathematically, it is possible to obtain patterns by taking actual field measurements.

ANTENNA GAIN: Gain (G) = Maximum Radiation Intensity from Antenna Maximum Radiation Intensity from Reference

ANTENNA TILT: Electrical Tilt: This is done with the help of phase shifters.The phase of the feed(voltage) to the dipoles is changed further leading to change in the radiation pattern in a better manner. Mechanical Tilt: In this you bend the antenna mechanically without any change in the internal ckt. The major lobe will become heart shaped in case of larger tilts.

The efficiency of a cellular network depends of its correct configuration and adjustment of radiant systems: their transmit and receive antennas.And one of the more important system optimizations task is based on correct adjusting tilts, or the inclination of the antenna in relation to an axis. With the tilt, we direct irradiation further down (or higher), concentrating the energy in the new desired direction. When the antenna is tilted down, we call it 'downtilt', which is the most common use. If the inclination is up (very rare and extreme cases), we call 'uptilt'.

The tilt is used when we want to reduce interference and/or coverage in some specific areas, having each cell to meet only its designed area.

Module C: RF Survey( Radio Frequency Survey)
RF survey is carried out to find out suitable location for BTS cell site giving best desired result on RF. RF Survey is done after the RF planning. RF planning data is created based on indoor & outdoor coverage criteria in the circle where mobile services are to be provided.

RF survey is important because it gives visual details to RF planner. Based on these details planner can create better model. Two types of RF survey is conducted: a) Nominal Survey b) Hot Spot Survey Tools used during the RF survey: a) GPS b) Digital Camera c) Magnetic Compass d) Map Info Software e)Measuring Tape f)Binocular

Important points to be checked during RF Survey:

a) Type of area- Residential/commercial b) Type of Population- Income wise c) Any hilly areas or rivers or forest falling & direction d) Type of buildings available e) Check for immediate obstructions f) Check for coverage objectives RF site survey is carried out in the following steps:  Collect list of Nominal’s to be surveyed, from the customer. In case of new town surveys where Nominal’s are not provided, survey the town and provide a nominal for suitable site location.   Use the survey report template forwarded by the customer. Identify physical location of the proposed nominal and locate 3 candidates (maximum) for each nominal, as per search ring size suggested by the customer.   Survey the site for RF suitability. Record Latitude and Longitude, building height etc. of the proposed candidates.

LOS (Line of Sight): By definition, line of sight is the visual line of sight that is determined by the ability of the average human eye to resolve a distant object. Our eyes are sensitive to light but optical wavelengths are very short compared to radio wavelengths. Accurate radio transmission depends on a clear path between radio antennas known as Line of Sight.

FRESNEL ZONE: Now the zone surrounding the RF LOS is said to be the Fresnel zone. Fresnel zone named for physicist Augustine-Jean Fresnel. To maximize receiver strength, one needs to minimize the effect of the out-of-phase signals by removing obstacles from the radio frequency line of sight (RF LOS). The strongest signals are on the direct line between transmitter and receiver and always lie in the first Fresnel zone.If unobstructed, radio waves will travel in a straight line from the transmitter to the receiver. But if there are obstacles near the path, the radio waves reflecting off those objects may arrive out of phase with the signals that travel directly and reduce the power of the received signal.

   

At the time of Calculating FZ radius we use frequency as given : For 0 to 15 km distance we have to use 15Ghz More than 15km we have to use 7Ghz frequency. But when u make calculation then we have put frequency in Mhz..e.g-15 GHz=15*10^3*10^6 = 15*10^3Mh

Module C: 2G & 3G RF Drive Test
Means collecting data on vehicle movement. Its variation has also intuitive: Walk Test, i.e., collect data by walking areas of interest. a) Coverage area b) Coverage –Indoor & outdoor c) Speech Quality d) Interference

e) Call drops in the network

The main types of Drive Test are :     Performance Analysis Benchmarking/Comparative Drive Test SCFT(Single Cell Functionality Test)) Cluster Drive Test

There are many drive test tools in market which is used by us for Drive Test. Drive Test Software tools are used by us:      TEMS(8.0.3,9,10,11,12)NEMO,PROBE,AGILENT DONGLE (Related tools) MOBILE ( W995 FOR TEMS,U 120E FOR PROBE ETC) TESTING SIM OF OPERATOR GPS 72,70 OR MOUSE GPS

Following is the procedure and parameters that need to checked while performing Drive Test for a New Site.          CPC (Cell Parameter Check) MOC (Mobile Originated Calls) MTC (Mobile Terminated Calls – Prepaid to Postpaid) SMS (Short Messaging Service) GPRS Intra Site Handover Inter Site Handover Idle Drive (Normal Drive & Frequency Lock Drive) Dedicated Drive

Radio Parameters:

    

RxLev : Receiving level in terms of dBm that mobile is receiving from the site. Range of -30 dBm to -110dBm. RxQual : Quality of voice which is measured on basis of BER. Range of RxQual 0 -7. FER : Frame Erasure Rate it represents the percentage of frames being dropped due to high number of non-corrected bit errors in the frame. It is indication of voice quality in network.



BER:-Ratio of the number of bit errors to the total number of bits transmitted in a given time interval.



BER is a measure for the voice quality in network.. Depending on BER RxQual is measured. E.g., BER 0 to 0.2 % corresponds to RxQual 0. Max. BER countable and useful is up to 12.8 % which corresponds to RxQual of max. 7.



SQI : SQI is a more sophisticated measure which is dedicated to reflecting the quality of the speech (as opposed to radio environment conditions). This means that when optimizing the speech quality in your network, SQI is the best criterion to use.



SQI is updated at 0.5 s intervals. It is computed on basis of BER and FER. For EFR 30, FR – 21 & HR – 17 are respectively ideal values.



C/I : The carrier-over-interference ratio is the ratio between the signal strength of the current serving cell and the signal strength of undesired (interfering) signal components. It should be at least > 9 .

HANDOVER:     Maintains Call Continuity. Controlled by BSS. Based on RF subsystem criteria or traffic loading considerations. Both MS and BTS provide RF link measurements to the handover process.

Handover Types:     Within same Base Transceiver Station (Intra-BTS) Between different BTSs served by same BSC (intra- BSS/inter-BTS) Between different BSSs within same MSC (intra-MSC/inter-BSS) Between different MSCs (inter-MSC)

INTERFERENCE Interference is nothing but the unwanted signal or noise. EFFECTS OF INTERFERENCE a) Interference is a major factor which affects network performance. b) It reduces the signal quality in network. c) It makes bit errors in the received signal. d) The up link and down link signal strength are affected by interference. MAJOR SOURCES OF INTERFERENCE a) other user Equipment in the same site. b) Nearer BTS on the same frequency. c) Due to environment TYPES OF INTERFERENCE There are two types of interference



Co-channel interference Co-channel interference is caused because of frequency reuse pattern (Different Sites using same set of frequency. For minimizing the co-channel interference, co-channel cells should be separated by a minimum distance and also by set various frequencies.



Adjacent channel interference Adjacent channel interference is caused by adjacent in frequency to the desired signal and also due to imperfect receiver filters in mobile equipment. It can be reduced by careful filtering and channel assignments.

3G Drive Test Procedure:

Radio Network Initial Tuning for WCDMA
  Preparations 
Parameter Audit Drive Testing & Post Processing Analysis & Change Proposals Change Verification & Reporting

Commercial Launch

WCDMA SERVING SET: Active Set (AS): The cells involved in soft handover and measured by the UE.

Monitored Set (MN): The monitored set is created from the neighbor cell lists of all the cells in the Active Set. The max number of cells in each set is 32. Unmonitored set: cells excluded from MN set because MN set is full. UE is not ordered to measure them. Detected Set (DN) : The intra frequency cells detected by the UE but not part of Active Set or monitored set. (Can then be an Unmonitored or a Missing neighbor) PILOT Pollution: Simply speaking, when the number of strong cells exceeds the active set size, there is “pilot pollution” in the area. Typically the active set size is 3, so if there are more than 3 strong cells then there is pilot pollution. Definition of “strong cell”: pilots within the handover window size from the strongest cell. Typical handover window size is between 4 to 6dB. For example, if there are more than 2 cells (besides the strongest cell) within 4dB of the strongest cell then there is pilot pollution. CPICH RSCP: The CPICH RSCP is the key measurement for DL coverage. The CPICH RSCP is an RXLEV measurement. The CPICH RSCP (Received Signal Code Power) is the received power on one code measured on CPICH. CPICH (Common Pilot Channel) RSCP—Received power on one code measured on the pilot bits of the primary CPICH. The reference point for the RSCP is the antenna connector at the mobile station Range is for CPICH RSCP is from –115dBm to -25 dBm. CPICH Ec/IoThe CPICH Ec /Io is the key measurement for radio optimization for CDMA. The CPICH EC/I0 measures the soft radio capacity. This measurement is for:    Cell re-/selection DL open-loop power control Soft HO and inter-frequency Hard HO

UE Tx Power:The UE TX power is the key measurement to analyze UL coverage.



It is the only uplink measurement that is available at the UE side. It is defined in the 3GPP TS25.215 as the total UE transmitted power on one total UE transmitted power on one carrier at the UE antenna connector. The reporting range for UE transmitted power is from -50 dBm to 33 dBm

RSSI:RSSI-Received signal strength indicator, the wideband received power within the relevant channel bandwidth. Measurement shall be performed on downlink carrier.  The reference point for the RSSI is the antenna connector at the mobile station

SIR:Signal-to-interference ratio, defined as: (RSCP/ISCP)×(SF/2), where ISCP = interference signal code power, the interference on the received signal Measured on the pilot bits.    Only the no orthogonal part of the interference is included in the measurement. SF = the spreading factor used. The SIR shall be measured on DPCCH after RL combination. The reference point for the SIR is the antenna connector of the mobile station. HSDPA TESTING/HSUPA TESTING:

Module D: RF Optimization & Planning
RF Optimization:
Optimization is an important step in the life cycle of a wireless network. Drive testing is the first step in the process, with the goal of collecting measurement data as a function of location. Once the data has been collected over the desired RF coverage area, it is output to post-processing software. Engineers can use the collection and post-processing software to identify the causes of RF coverage or interference problems and determine how these problems can be solved. When the problems, causes and solutions have been identified, steps are performed to solve the problems. Network statistics are also an important step in analysis and troubleshooting of RF issues. Analyzing daily and weekly basis KPI trend for parameters like Call Setup Success Rate, Drop Call Rate (DCR), Rx Quality & level, Handover Success Rate etc. and resolve problem promptly. Analyzing & rectifying Neighbor discrepancies, non-symmetrical Neighbor, adjacent Co-BISC, Co- CH and Adj-CH neighbors. Responsible for Post processing of drive data and implementing the changes with the help of ACTIX post processing tool. Analysis of daily reports of OMCR and modification of undeclared neighbor list for each Sector to maintain KPIs. Optimization process can be explained by below step by step description: Problem Analysis  Analyzing performance retrieve tool reports and statistics for the worst performing BSCs and/or Sites      Viewing Reports for BSC/Site performance trends Examining Planning tool Coverage predictions Analyzing previous drive test data Discussions with local engineers to prioritize problems Checking Customer Complaints reported to local engineers

Checks Prior to Action:

    

Cluster definitions by investigating BSC borders, main cities, freeways, major roads Investigating customer distribution, customer habits (voice/data usage) Running specific traces on Network to categorize problems Checking trouble ticket history for previous problems Checking any fault reports to limit possible hardware problems prior to test

Subjects to Investigate
               Non–working sites/sectors o In–active Radio network features like frequency hopping Disabled GPRS Overshooting sites – coverage overlaps Coverage holes C/I, C/A analysis Drop Calls Capacity Problems Other Interference Sources Missing Neighbors One–way neighbors Ping–Pong Handovers Not happening handovers Accessibility and Retain-ability of the Network Equipment Performance



Faulty Installations

After the Test  Post processing of data Plotting RX Level and Quality Information for overall picture of the driven area     Initial Discussions on drive test with Local engineers Reporting urgent problems for immediate action Analyzing Network feature performance after new implementations Transferring comments on parameter implementations after new changes

BENCHMARKING:  Benchmarking service based on field data collection and a comparative analysis process involving the quality and coverage of different networks audited.  This analysis is followed by a full report and a set of recommendations that allow the customer to identify their strengths and weaknesses compared to its major competitors, always with the objective of improving the network quality by applying the recommendations.

RF Planning:
RF planning plays a critical role in the Cellular design process. By doing a proper RF Planning by keeping the future growth plan in mind we can reduce a lot of problems that we may encounter in the future and also reduce substantially the cost of optimization.On the other hand a poorly planned network not only leads to many Network problems , it also increases the optimization costs and still may not ensure the desired quality. Nominal planning , RF Network Planning, Neighbor planning , Coverage Planning & Frequency Planning, Preparation of Database (LAC, CI,…) , Creating daily KPI report based on Daily Counter. Taking Status of Survey Site & Co-ordinate with Survey Engineer & Survey Co-ordinator.

RF Planning Tools:    Planet, Pegasus, Cell Cad Net plan by Motorola, TEMS by Ericsson

   

Actix Atoll Planet Net dim by Nokia

Network Planning Tool:Planning tool is used to assist engineers in designing and optimizing wireless networks by providing an accurate and reliable prediction of coverage, doing frequency planning automatically, creating neighbor lists etc.RF Network Planning and Optimization Software and Tools ... like Actix, XCAP, Atoll, Planet With a database that takes into account data such as terrain, clutter, and antenna radiation patterns, as well as graphical interface, the Planning tool gives RF engineers a state-of-the-art tool to:    Design wireless networks Plan network expansions Optimize network performance

Traffic Modelling Tools:   Traffic modelling tool is used by the planning engineer for Network modelling and dimensioning. It helps the planning engineer to calculate the number of network elements needed to fulfil coverage, capacity and quality needs.  Net dim by Nokia is an example of a Traffic modelling tool.

Project Management Tools:  Designing a cellular system - particularly one that incorporates both Macro cellular and Microcellular networks is a delicate balancing exercise.  The goal is to achieve optimum use of resources and maximum revenue potential whilst maintaining a high level of system quality.  Full consideration must also be given to cost and spectrum allocation limitations.



A properly planned system should allow capacity to be added economically when traffic demand increases.

RF PLANNING PROCEDURE: Terrain, Clutter, Vector data acquisition and setup: --Procure the terrain, clutter and vector data in the required --Setup these data on the planning tool. --Test to see if they are displayed properly and printed correctly on the plotter. Setup site tracking database: --This is done using Project management or site management databases. resolution.



Marketing Analysis and GOS (Grade of Services) determination:

--Marketing analysis is mostly done by the customer. --Growth plan is provided which lists the projected subscriber growth in phases. --GOS is determined in agreement with the customer (generally the GOS is taken as 2%)

--Based on the marketing analysis, GOS and number of carriers as inputs, the network design is carried out. Zoning Analysis: -This involves studying the height restrictions for antenna heights in the design area  The objective of a cellular system is to provide quality communication to the maximum number of users in a defined area.    The number of users supported by the system can be increased by using more frequencies. Frequency resources are however always limited. Hence RF Planning engineers are required to maximise spectrum efficiency.

Site Location    Proper site location determines usefulness of its cells. Site are expensive and have to be chosen carefully. The planner needs to visit each and every site.

Good Site Selection  We need to understand various factors we must take into account to ensure that the selected site is good.    Simple way is to ask yourself three questions 1) Why am I putting this site ? 2) Will this selected site serve that purpose ?

Module E: RF Data Preparation
Steps for Making RF Report using MAPINFO Tool: 1.Export the log files( For this u can see previous pages) 2.After making export we will open our export in MapInfo. 3.For making report see in your MapInfo .At the top of your MapInfo there is map or not? Of course it will be there then follow this: Go to Map-Create thematic map-ok-here we will see templates( From here we mostly use point rage default)-Next---Choose which you want-Next--arrange of ranges(How we arrange:-Go to custom-ranges(We can change as our requirement)--Reclac-ok--style--Marlette--ok-------- To open MapInfo Professional

Choose Start > Programs > MapInfo > MapInfo Professional 6.5 or click on the shortcut on the desktop if one is created.  To analyze drive test data using MapInfo, you will need an input data and this input data is the TEMS exported log files. If you have not exported log files, check the previous pages on how to export log files using TEMS Investigation. MapInfo can be used to analyze RX_LEV and RX_QUAL as we shall see in the following To create a Thematic Map simply following the steps below: Step 1:  In this step click on Open Table on the toolbar or menu bar and the Open Table dialogue box comes up Open Table window

 

File name Select file name where saved Files of type Select “MapInfo (*.tab)”

Preferred View Change from “Automatic” to “Current Mapper. After selection click Open The result (map path) will be displayed as shown-

Creating Thematic Map To create Thematic Map, from menu bar choose Map > Create Thematic Map. The Create Thematic Map - Step 1 of 3 dialog displays. Creating a thematic map is a three-step process: Step 1: Choosing A Type Of Thematic Map Thematic templates allow you to make a thematic map based on values and settings in our default types, alter these settings and/or save them as a new template you can use again. When you first create a thematic map, you begin by selecting a template that you can modify to suit your requirements. You cannot create a theme without using an existing theme template.

  

To create a thematic map you can only use the “Ranges” under “Type” (see fig.) Type: Select Ranges Template Name: Select Template Name (e.g. Region Ranges, Solid Yellow-Blue,Dark



Click on Next

Step 2:     Step 3:  Customizing Your Thematic Map. The last step allows you to customize your thematic map, or create the map based on the default  settings. You can also preview the map's legend before you display the map, and change the legend's label order. Select a Table and a Field. Table: Select a table (these tables are log files) Field: Select a field (specify what you want to analyze e.g.RXLEV_FULL) Click Next



Preview

Displays a sample legend of the thematic map you are creating Legend label Order Ascending and Descending determines the order in which range and value labels (for ranged and individual values maps) and field labels (for all other thematic maps) appear in the legend.  If you are creating a ranged map, the order you specify is also shown in the Customize Range Styles dialog. 1. Choose Ascending to display ranges from lowest to highest value. 2. Choose Descending to display ranges from highest to lowest value. Customize:  The buttons in the Customize group enable you to change the default settings of particular aspects of your thematic map  Ranges - Allows you to customize settings on a ranged map. This option is available for ranged and grid maps.

Method For Customize:   Select ‘Custom’ # of Ranges: Select ‘4’ to define the ranges for RXLEV_FULL or Select ranges for RXQUAL_FULL   Define the minimum (>=Min) and maximum (<Max) ranges as shown in fig. 50 above. After defining the ranges, click Recalc. The window changes as shown below. ‘3’ to define the



Click on the Style Buttons at left to change style and see the next figure…



Select the symbol style color of your choice to define your range.

 

Click OK after defining all your colors. Legend - Enables you to customize your legend.

This option is available for all types of thematic maps



Define your ranges from the “Edit selected range here” and can also be modified through same.



Click OK

Template  The buttons in the Templates group enable you to specify a name for a template, save the thematic map as a template, and when modifying an existing theme merge the thematic map with another template. Save As :    Displays the Save Theme to a Template dialog. Type a unique name or select an existing name and overwrite it. If you overwrite an existing template, you are prompted to confirm this action.



Therefore, after customizing the ranges, style and legend for say RXLEV_FULL; you can save the template so that you use it again for other log files.



This will save you a lot of stress customizing severally.

For RXLEV_FULL, you may use the ranges defined below 35 – 66 (RXLEV>-75dBm) 20 – 35 (-90dBm=<RXLEV<-75dBm) 15 – 20 (-95dBm=<RXLEV<-90dBm) --1 – 15 (-110dBm=<RXLEV<-95dBm)



The size of the thematic map can be modified (i.e. made more presentable) from the tool bar .

     

Choose Layer Control > select Layer and click Display > Style override Font: Select font (select MapInfo Symbols) Size: Select size of your choice (preferably 6) Symbol: Select desired symbol Colour: Select desired colour Then click OK

For RX_QUAL, follow the same step as for RX_LEV but the customize range, style and legend will be different. The customize range, style and legend is as follows:



For making of all types of Report we have to follow same steps but little changes. we can also use ACTIX Tools. This tool is very -very useful for making report very easily and fast. Actix Analyzer offers the possibility to look at drive test data and scanner data to fully optimize a UMTS network. It allows the engineer to understand the causes and reasons fordrop calls and access failures.Analyzer offers an unprecedented capability to execute a detailed examination of message flows and automating statistical analyses of performance. Analyzer significantly accelerates the rollout, troubleshooting and optimization of the UMTS network. Actix has embedded intelligence in the software to allow the RF engineer to visualize specific events and understand real problems occurring in the network. Analyzer embodies our extensive experience as the market leader in optimization solutions for CDMA, UMTS and GSM.

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