Propagation Model

The advanced GSM/CDMA/WCDMA technological features and various services have attracted many subscribers and telecom operators. Study and modeling of the radio wave propagation model is the foundation of network planning, and is also the foundation of link and coverage estimation. The accuracy of the propagation model directly influences the scale of radio network planning, the accuracy of coverage estimation, and the layout of Node Bs.
Aware of the importance of propagation model’s accuracy, mPraxis has been devoted to the study of propagation model, and achieved rich experiences in practice.

In propagation model tuning, we simulate the test result with the field strength of the test point and the line between the test point and the transmitter, when transmission power and reception power are known. Usually, the final result of model tuning fulfills an average error of 0 and a minimal standard deviation. Here we use tools like Asset to make propagation model tuning.

CW Drive Tests

We perform Continuous Wave (CW) testing at various locations throughout the network to provide better insight into the radio signal’s propagation characteristics at these locations. This testing consists of installing the CW receiver equipment in a test vehicle and driving specified routes intended for coverage by a wireless site if constructed at the test transmitter location. The purpose of this testing is to measure the propagation of defined radio signals (at known TX power level, locations and frequency) to develop a baseline model. The equipment used to transmit and receive should remain consistent throughout all of the drive tests. Accuracy of the propagation modeling requires parameters of the test site configuration to be recorded accurately for each drive test performed. We support this activity by wither using Agilent Kit, Invex 3G kit sot TEMS kits.

Nominal Cell Plan

Nominal Cell Plan using standard planning tools for UMTS, GSM and CDMA like Asset, Cell Plan, Planet, Net Plan we determine
  1. Demand forecast service and location of demand. Outline desired area of coverage defined by Client via maps or software.
  2. Develop coverage objectives. Prepare coverage plan to meet objectives. Define building coverage penetration requirement for “Urban”, “Suburban” and “Rural”. Define GSM Link Budget
  3. Generate coverage plots
  4. Document and distribute radio base station dependent data. Identify the following cell site information based on client’s coverage and capacity design requirements:

    • Number of voice channels.
    • Effective radiated power.
    • Antenna radiation centre above ground level (AGL).
    • Sector/omni antenna and orientations.
    • Down-tilt angle
    • Frequency plan
    • Site name, site code and number
    • Provide map co-ordinates of base stations.
    • Create Cell Design Data (CDD) for each site.

  5. Frequency plan based on data collected in item 5 above.
  6. Prepare & submit nominal Cell Plan on ASSET and Frequency Plan.
  7. Approve the nominal cell plan
  8. Issue search rings
RF Survey of Search Area/ MW LOS survey and selection of suitable site candidates
  • Obtain general building information
  • Taking digital photos
  • Technical site survey (TSS) and preparation of the RF part of the TSS report
  • Performing line of sight (LOS) surveys for sites that are connected via MW links using Pathloss tools.
  • Preparation of site layout (from RF and MW transmission point of view), including information on antenna heights, antenna directions, location of the BTS and any other special needs to be captured for a particular site
  • Approval of the site layout through the Customer and contribution of the layout to the site folder
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