In Long-Term Evolution (LTE), the channel architecture refers to the organization and allocation of different types of channels used for communication between the User Equipment (UE) and the Evolved NodeB (eNB). LTE employs a flexible and efficient channel architecture to support various services and optimize resource utilization. Here are key components of the channel architecture … Read more
The MAC layer is oriented to the connections. Each connection corresponds to a service flow. The service flow defines the QoS parameters of PDU transmitted over the connection. The design core of the MAC protocol is the concept of service flow architecture on the connection. The service flow provides an uplink/downlink QoS management mechanism. An … Read more
Transmitting: After being processed at the MAC layer, the downlink data is sent to the physical layer inthe format of MAC PDU. The MAC PDU arranges the data block size according to the allocation results of radio resources at the MAC layer. After the data packets are processed through the channel coding, modulation, and IFFT … Read more
How Physical channel of LTE works in UL & DL?A distinction has to made between: The Physical channel The Physical signal The DL physical channels are: Physical DL Shared Channel (PDSCH) It is a shared channel used to carry user data, radio & core network, system information (BCH), paging message. Physical DL Control Channel (PDCCH) … Read more
Transport channels are then mapped on the physical channels which are sent over the air interface A CRC is calculated and appended to each TB. It allows the receiver to detect errors. It is used by retransmission mechanisms like H-ARQ Depending on the Transport Format and the radio quality, the TB is coded and interleaved. … Read more
A transport channel defines how and with what characteristics the information is transmitted. Inherited from the WCDMA, data on the transport channel is organized into “Transport Blocks”, TBs. A Transport block can be transmitted every TTI = 1 ms The “Transport Format”, TF, defines how the blocks can be transmitted: Transport block size, it depends … Read more
The following control logical channels have been defined by the 3GPP: BCCH, Broadcast Control Channel, used for the transmission of system control information. A UE needs to decode it before requesting a connection. PCCH, Paging Control Channel, is a downlink channel that transfers paging information and system information change notifications. This channel is used for … Read more
The MAC protocol provides the following services: Logical Channel to Transport channel mapping Scheduling: There is no dedicated channel allocated to a UE. Time and frequency resources are dynamically shared between the users in DL and UL. The scheduler is part of the MAC layer and controls the assignment of uplink and downlink resources. Multiplexing/Demultiplexing … Read more
The Radio Link Control (RLC) protocol provides the following services: Segmentation of SDU according to the size Re-Segmentation of PDU Radio Bearer to logical channel mapping Transfer of data in 3 modes: TM Transparent Mode Without retransmission. For real-time service. UM Unacknowledged Mode Without retransmission, but error statistics (BLER) It can be used for the … Read more