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What is SC-FDMA and how it works in LTE?

What is SC-FDMA and how it works in LTE? One of the major drawbacks of an OFDMA system is, that the transformation of a complex symbol mapped sequence (e.g. BPSK, QPSK, etc.) onto a small set of subcarriers produces time sequences that have high PAPR (Peak-to-Average Power Ratio). PAPR is the ratio between the maximum … Read more

Radio Protocol Architecture in LTE

Radio Protocol Architecture in LTE The EUTRAN radio protocol model specifies the protocols terminated between UE and eNB. The protocol stack follows the standard guidelines for radio protocol architectures (ITU-R M1035) and is thus quite similar to the WCDMA protocol stack of UMTS. The protocol stack defines three layers: the physical layer (layer 1), data … Read more

Different Tasks and States of RRC Protocol in LTE-EUTRAN

Different Tasks and States of RRC Protocol in LTE-EUTRAN The RRC protocol for EUTRAN is responsible for the basic configuration of the radio protocol stack. But one should note, that some radio management functions (scheduling, physical resource assignment for physical channels) are handled by layer 1 and layer 2 autonomously. MAC and layer 1 signaling … Read more

Physical Channel Types of LTE

Physical Channel Types of LTE The physical layer uses resource blocks to transmit binary coded information in QPKS, 16QAM or 64QAM or OOK modulation form. Physical channels determine how data is processed and then mapped via dynamical scheduling onto resource blocks. Thus physical channels also in EUTRAN represent the available physical resources. Like transport channels, … Read more

How Transport Channel Processing in LTE?

How Transport Channel Processing in LTE? Transport channels are block oriented transmission services and transmit one or more transport blocks per transmission time interval (TTI). The TTI is 1 ms (e.g. one sub-frame). Transport blocks may in general have variable size. Typically the number of transport blocks that can be transmitted in a TTI depends … Read more

Layer and channel relationship in LTE

Layer and channel relationship in LTE The radio interface is composed of different layers in order to set up, reconfigure and release the radio bearer services. The protocol layer is composed of physical layer (layer 1), data link layer (layer2), and the network layer (layer3). In the E-UTRAN layer 2 is divided into two sub-layers: … Read more

Synchronization in LTE Mobile “Switch On”

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

PLMN selection in “IDEL Mode” for LTE-UE

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

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

Gigabit LTE

Gigabit LTE – definition, class, technology, devices, availability Gigabit LTE is an important springboard for mobile 5G data connectivity. It contains a number of building blocks for the new network. Gigabit LTE is an advanced form of LTE, the 4G radio technology that mobile operators use to connect mobile devices. Gigabit class lte what is … Read more