Power ramping in LTE

Power ramping in LTE Open loop power control together with optional power ramp-up is used during the random access process at the beginning of the connection until more accurate control information is available. Power loss due to transmission distance depends on to the increase of the distance between NodeB and the UE. In such a case, feedback information … Read more

Non-contention vs Contention Access procedure in LTE

Non-contention vs Contention Access procedure in LTE Random access procedure is performed for the following five events: • Initial access from RRC_IDLE; • RRC Connection Re-establishment procedure; • Handover; • DL data arrival during RRC_CONNECTED requiring random access procedure; • UL data arrival during RRC_CONNECTED requiring random access procedure; E.g. when UL synchronization status is … Read more

Uplink Power Control Calculation in LTE

Uplink Power Control Calculation in LTE Transmit power of PUSCH in subframe i is defined by PPUSCH (i) = min{PMAX,10 log10 (MPUSCH (i)) + PO_PUSCH ( j) +α ( j) ⋅ PL + ΔTF (i) + f (i)} [dBm] Pmax: max. allowed power, MPUSCH: number of scheduled RBs, PL: pathless [dB]. ΔTF (i) = 10 … Read more

Downlink Power control in LTE

Downlink Power control in LTE The eNodeB determines the downlink transmit energy per resource element (lte epre). Downlink cell-specific reference-signal (RS) lte epre is constant across the downlink system bandwidth and constant across all subframes until different cell-specific RS power information is received. The downlink RS lte epre is given by the parameter Reference-signal-power provided by higher … Read more

Principle of Power control in LTE

Principle of Power control in LTE Power control – already being applied in 2nd and 3rd generation networks – has high potential for improvement of the performance of mobile networks. Main benefits are: 1. It can bring down the interference in up- and downlink and hence enhances the capacity of the networks. 2. Additionally it … Read more

Timing Advance in LTE

Timing advance lte what is timing advance in lte: -The eNB measures the required timing advance based on the received UE signal arrival time. It commands the UE to adjust the transmission time. This is performed on a per-need basis. It is signaled by means of a special MAC control element; LCID = 11101. The … Read more

Evaluation process for Cell selection in LTE

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 procedure and criteria in LTE UE

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

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?

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