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PS core network

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The PS core network consists of two parts, the traditional General Packet Radio Service (GPRS) core network and the new Evolved Packet System (EPS) core network. The PS core network connects mobile subscribers to Packet Data Networks (PDNs) such as the Internet, corporate networks or operator services networks.  a functional overview of the PS core network. Logical entities and interfaces are shown in black and form a 2G/3G network, while the blue boxes and lines in Figure  show the LTE/EPC related parts. The LTE/EPC network can be regarded as an extension and evolution of existing 2G/3G networks. From a node implementation perspective, there is no strict border between the two networks. The corresponding logical entities of GPRS and EPS networks can be deployed concurrently in Ericsson PS core nodes, such as the SGSN-MME and EPG; these are marked in red. In addition, Ericsson GPRS nodes can be upgraded with EPC functionality by software only. Network evolution i...

Ericsson RAN - Radio Access Networks Associate Certification

Overview – Ericsson RAN - Radio Access Networks Associate Certification RAN Fundamentals ·          Describe general RAN architecture ·          Describe radio design principles ·          Describe air interface principles ·          Describe signaling, protocols and layers ·          Describe radio network basic functionalities ·          Describe RAN performance LTE RAN Technology ·          Describe the technology and characteristics of LTE RAN ·          Describe the products & solutions, functionality and features ·          Describe main advantages/values. WCDMA RAN Technology ·   ...

Link Budget in WCDMA / UMTS

Link budget planning is part of the network planning process, which helps to dimension the required coverage, capacity and quality of service requirement in the network. UMTS WCDMA macro cell coverage is uplink limited, because mobiles power level is limited to (voice terminal 125mW). Downlink direction limits the available capacity of the cell, as BTS transmission power (typically 20-40W) has to be divided to all users. In a network environment both coverage and capacity are interlinked by interference. So by improving one side of the equation would decrease the other side. System is loosely balanced by design. The object of the link budget design is to calculate maximum cell size under given criteria: Type of service (data type and speed) Type of environment (terrain, building penetration) Behavior and type of mobile (speed, max power level) System configuration (BTS antennas, BTS power, cable losses, handover gain) Required coverage probability

What is HARQ and explain cell breathing.

Hybrid automatic repeat-request(HARQ) :Data and voice blocks are transmitted in 10 ms time-intervals called frames. At each frame and for each transmission the SIR is evaluated and used to derive the Block Error Rate (BLER).  Each block is then considered correct or erroneous according to a random experiment based on the BLER. For the packet switched traffic only, an ideal ARQ procedure is adopted, i.e., the transmitted block is kept in the transmitting queue in case of error and is cancelled otherwise Cell breathing is the constant change of the range of the geographical area covered by a cellular telephone transmitter based on the amount of traffic currently using that transmitter. When a cell becomes heavily loaded, it shrinks.

How many codes are required to get 7.2Mbps in HSDPA?

5 codes and qpsk= 1.8mbps; 5 codes and 16 qam= 3.6 mbps; 10 codes and 16 qam= 7.2 mbps; 15 codes and 16 qam= 14.4; 15 codes and 64 qam= 21.1mbps; 15 codes and 16 qam(mimo)=28mbps; 16 codes and 64 qam(mimo)=42.2mbps

WCDMA System message

SIB1 : NAS Information. UE Timers and counters to be used in RRC Idle & Connected State, SIB2 : List of URA Identities SIB3 : Parameters for Cell Selection and Reselection SIB4 : Same as SIB3 but used in Connected State SIB5 : Configuration parameters of common physical channels in a cell. PCH and PICH Info (CPCH) SIB6 : Configuration of Common and Shared physical channel SIB7 : Contains fast changing UL interface params and dynamic. As this is changes often so controlled by timer SIB8 : Used in FDD . Static CPCH info of cell. Used in Connected mode only SIB9 : CPCH info. As it changed often, controlled by timers connected mode only. SIB10 : DRAC Procedure, used when CELL_DCH controlled by timer SIB11 : Measurement control information to be used in CELL SIB12 : Same as SIB11 but used in connected mode only SIB13 : For ANSI-41 . It also has 4 associated SIBS 13.1 to 13.4. Reference to subblocks. Used when System is ANSI-41. SIB14 : Parameters for common and dedicat...

PACKET DATA APPLICATIONS

The WCDMA/GSM GPRS system supports end-users wishing to access the Internet and Intranets using a WCDMA UE or GPRS MS as the connecting device. Some examples of user applications enabled by 3G are given below: ·           Video Telephony and Video Conferencing ·           Broadband Web Browsing and Multimedia Streaming; for  example, video clips, news on demand and music ·          Mobile Broadband ·           Multimedia Messaging (voice mail with pictures) ·           Location-based Servic Additionally, all data services enabled by 2.5G technologies will also be available. For example, some horizontal applications enabled by 2.5G are: ·           E-mail ·       ...