Richard Jhon

Evaluation process for Cell selection in LTE S-CRITERION The cell selection criterion S is a pre-condition for suitable cells. The conditions for E-UTRAN, UTRAN FDD and GSM cells are listed in the figure. R – CRITERION – CELL RESELECTION The cell reselection evaluation process depends on whether Hierarchical Cell Structure (HCS) is used or not. … Read more

PLMN Selection Process in LTE The UE scans all RF channels in the UTRAN band according to its capabilities to find available PLMNs. On each carrier, the UE searches for the strongest cell according to the cell search procedure (refer cell searching) and read its system information in order to find out which PLMN the … Read more

Cell selection and reselection in LTE UE To get service from the selected PLMN, the UE performs two types of  procedures: LTE cell selection and LTE cell reselection CELL SELECTION in LTE Upon PLMN selection, LTE UE uses “cell selection” for fast cell searching to camp on. To receive system information LTE UE tunes to … Read more

How UE Switch to Service types in LTE? The action of camping on provides access to services. The network provides different levels of service to a UE in either Idle mode or Connected mode. Three levels of services are defined: LIMITED SERVICE: emergency calls on an acceptable cell. Acceptable cell: UE may camp to obtain … Read more

PLMN selection in “IDEL Mode” for LTE-UE When an UE is switched on, it attempts to make contact with a PLMN. The selection of the PLMN could be either automatically or manually. • Automatic mode: Utilizes a list of PLMN to be selected in priority order. • Manual mode: The mobile station indicates available PLMN … Read more

Synchronization in LTE Mobile “Switch On” Primary and Secondary Synchronization Signals occupy 2 blocks of symbols per 10 ms (central 72 subcarriers for all channel bandwidths). An example is shown below for 72 subcarrier- (1.4 MHz) / single antenna case. During the initial cell search, the mobile station searches for the strongest cell. It then … Read more

Uplink data transmission in LTE The mapping of transport channels and UL control information (UCI) to physical channels is a task of the physical layer (PHY). Furthermore reference signals are provided by the physical layer which do not transfer any higher layer information. Logical channel mapping is provided by the MAC layer. Physical channel for … Read more

System information & DL-SCH data in LTE System information 1920 bits or 1728 bits are to be transmitted for normal or extended CP resp.. The PBCH is transmitted every 40 ms. The bit scrambling depends on the cell id and is starting in radio frames 0, 4, 8 … . PBCH uses QPSK. I.e. 960 … Read more

RE – groups & CFI – Control Format Indication in LTE RE – groups & CFI – Control Format Indication in LTE is as below. RE – groups In order to support DL control information mapping, RE-groups are defined. Four useful symbols are bundled, useful in the sense that RE’s carrying the cellspecific reference symbols … Read more