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** Conditions :

• capacity not constant.
• separate analysis for UL/DL.
• joint coverage/capacity analysis.
• HO areas and levels affect directly system capacity.
• basic shared resource is power.

** Objective parameters :


• coverage.
• capacity (blocking).
• good link quality (BER, FER).
• throughput delay, for packet services Methods.
• preplanned during network planning process.
• real time radio resource management.
• real time power control.








Resource reservation for handling expected traffic without congestion.
           – load per cell/sector, handover areas.

Sets allowable “power budget” available for services.
           – load higher than expected.
           – load “badly” distributed.
           – implements statistical multiplexing.

Estimates average power/load, variations of it are taken care in run time by RRM.
           – maximal allowed load versus average load.

Planning methods

•  Preparation phase.
           – Defining coverage and capacity objectives.
           – Selection of network planning strategies.
           – Initial design and operation parameters.

• Initial dimensioning.
           – First and most rapid evaluation of the network elements count and capacity of these elements.
           – Offered traffic estimation.
           – Joint capacity coverage estimation.

• Detailed planning.
           – Detailed coverage capacity estimation.
           – Iterative coverage analysis.
           – Planning for codes and powers.

• Optimisation.
           – Setting the parameters.

• Soft handover.

• Power control.

• Verification of the static simulator with the dynamic simulator.
           – Test of the static simulator with simulator where the users actual movements are modelled.

  It was agreed that any new security architecture must be based on an evolution of GSM and must adopt four basic principles:

•   It will take into account the additional features needed for actual or predicted change in the operating environment

•   It will maintain compatibility with GSM wherever possible

•   It will retain those features of GSM that have proved to be robust and useful to the user and network operator

•   It will add or enhance features to overcome actual or perceived weaknesses in 2G system

1-  Additional features :

  One of the main reasons for the development of the 3G system to make higher value services available to as many users as possible world wide, using a universal design of the handset. However, this increases the number of relationships, as the number of Users, Service Providers, and Network Operators in the market expands.

  This increased level of service interaction increases the number of potential attackers and the opportunities open to them. This was not too much of a problem in the initial roll out of GSM, as there were a relatively small number of operators and the risk of compromise was low.

  For 3G, the networks are getting smaller and more numerous, so opportunities for hackers and other abusers of networks will increase. Even if deliberate abuse is not considered likely, unintentional mishaps may occur as a result of the complexity and the rate of new service introduction.

Planning

     • Planning should meet current standards and demands and also comply with future requirements.
     • Uncertainty of future traffic growth and service needs.
     • High bit rate services require knowledge of coverage and capacity enhancements methods.
     • Real constraints
               – Coexistence and co-operation of 2G and 3G for old operators.
               – Environmental constraints for new operators.
     • Network planning depends not only on the coverage but also on load.

Objectives of Radio network planning

     • Capacity:
               – To support the subscriber traffic with sufficiently low blocking and delay.
     • Coverage:
               – To obtain the ability of the network ensure the availability of the service in the entire service area.
     • Quality:
               – Linking the capacity and the coverage and still provide the required QoS.
     • Costs:
               – To enable an economical network implementation when the service is established and a controlled network expansion during the life cycle of the network.

     UMTS (Universal Mobile Telecommunications Service) is a third-generation (3G) broadband, packet-based transmission of text, digitized voice, video, and multimedia at data rates up to 2 megabits per second (Mbps). UMTS offers a consistent set of services to mobile computer and phone users, no matter where they are located in the world. 



   

 I want to speak about messages in CDMA , how it sent and what the call processing

**  In CDMA, most call processing events are driven by messages.
** Some CDMA channels exist for the sole purpose of carrying, they never carry user’s voice traffic.
          • Sync Channel (a forward channel).
          • Paging Channel (a forward channel).
          • Access Channel (a reverse channel).
          • On these channels, there are only messages, continuously all of the time.
** Some CDMA channels exist just to carry user traffic.
          • Forward Traffic Channel.
          • Reverse Traffic Channel.
          • On these channels, most of the time is filled with traffic and messages are sent only when there is something to do.
** All CDMA messages have very similar structure, regardless of the channel on which they are sent.

    The evolution process of the CDMA standards is roughly divided into the following stages :

   CdmaOne namely, IS-95A and IS-95B It mainly supports the voice service, belonging to 2G communications.

   cdma2000 1X: It can support both voice and data services. The max. Data rate can reach 153 kbps, belonging to 3G mobile communications.

   cdma2000 1xEV-DO: As the enhanced version of cdma2000 1X at stage 1, it supports data services, with max. forward rate being up to 2.4 Mbps.

   cdma2000 1xEV-DV: As the enhanced version of cdma2000 1X at stage 2, it supports both voice and data services, with max. data rate being up to 4 Mbps, and even higher.

   

Hello ,
My name is mahmoud . A communications engineer .I'd like to share all things that i know with you .This blog will discuss all things about Communications engineering and Communications networks as cellular ( GSM , UMTS and LTE ) and networks ( WiFi - WiMAX ).
I wish that i can help each one who needing help or searching for any information .
Thanks ,
Mahmoud