Synchronization & BCH for TDD Frame in LTE Synchronization: Purpose: Achieves alignment between the base station (eNodeB) and User Equipment (UE) in LTE Time-Division Duplex (TDD) frames. Methods: Time synchronization ensures proper timing, and frequency synchronization aligns the carrier frequency. Importance: Synchronization is critical for avoiding interference and optimizing signal reception. Broadcast Channel (BCH): Function: … Read more
Which Cell Parameters needs to Obtain in LTE? To provide the most critical information to the UEs, the eNodeB uses the BCH channel The information is sent on pre-defined time-frequency resources. This information is organized into different information blocks: The MIB, the Master Information Block. System Frame Number DL -downlink System Bandwidth Number of Transmit Antennas … Read more
RACH(Random Access Channel) Uplink only. Used by the MS when making its first access to the Network. The reason for access could be initiation of a call or a page response. AGCH (Access Grant Channel) Downlink only. Used for acknowledgement of the access attempt sent on RACH. Used by the network to assign a signaling … Read more
OFDMA is essentially a hybrid of FDMA and TDMA: Users are dynamically assigned subcarriers (FDMA) in different time slots (TDMA) . The advantages of OFDMA start with the advantages of single-user OFDM in terms of robust multipath suppression and frequency diversity. In addition, OFDMA is a flexible multiple-access technique that can accommodate many users with … Read more
After the power on, the UE knows: the UE category and capability. the preferred PLMN. the carriers. The UE needs to know: The frame synchronization to be able to decode the DL radio frame. The cell parameters to be able request a connection. The UE can use: The PSS: Primary Synchronization Signal. The SSS: Secondary … Read more
When the UE has obtained system information, it has to request an RRCconnection. Like it has no dedicated resources, the UE requests the connection using the Random Access Procedure using common uplink resources. At the end of the procedure, the UE is RRC connected UE and eNodeB are able to exchange data using dedicated radio … Read more
When the UE is powered up, it has to be RRC connected to be able to exchange data and signaling with the network. After the RRC connection, the Initial network attach allows to establish all the bearers to carry the data from the UE to the gateway. After the RRC connection, Signaling Radio Bearers (SRBs) … Read more
1. Random access channel (RACH) It is an uplink channel used for MS randomly access to network by requesting for an SDCCH. The request includes a 3bit setup reason (call request, paging response, location update request and short message request etc.) and a 5bit random reference number for MS to differentiate the access granted messages. … Read more
The UE is requested to send either periodic or a periodic reports concerning • Rank indication (RI) Reports are applicable for closed- and open-loop spatial multiplexing. In case of open-loop TRI=1 corresponds to transmit diversity and TRI>1 to large delay CDD. • Precoding matrix indicator (PMI) PMI reporting is relevant for spatial multiplexing (open- and … Read more