Hybrid ARQ (HARQ) leads to higher efficiency in transmission and error correction. There is one HARQ entity per UE with 8 stop-and-wait processes for each HARQ entity. Both incremental redundancy and chase combining are supported. The number of HARQ retransmissions targeted by the HARQ protocol depends on the network configuration. The BLER seen by RLC … Read more
Handover principles Lossless Packets are forwarded from the source to the target. Network-controlled Target cell is selected by the network, not by the UE. Handover control in E-UTRAN (not in packet core). UE-assisted Measurements are made and reported by the UE to the network. Late path switch Only once the handover is successful, the packet … Read more
Typically, the data rate available at the radio interface is lower than the data rate available on the network interfaces. Thus, when a certain rate data service is higher than the data rate of the LTE radio interface, this leads to buffering in the UE and the eNodeB. This buffer allows the programmer to the … Read more
Here i write about Radio Link Control -RLC in LTE in a simple word. The RLC layer is located between the PDCP ( the “top” layer) layer and MAC layer (the “lower” layer). Communicates with the PDCP layer through a service access point ( SAP ) , and the MAC layer via logical channels. The … Read more
UE Accessibility Verification If the best cell on the LTE frequency have banned or are protected, up to exclude This cell from cell selection list. In that case may consider UE the cell on the same frequency, if banned cell indicates (by using fields ‘ intraFreqReselection ‘ in SIB1), intra-frequency selection is not allowed for … Read more
Cell selection consists of the UE seeking stronger cell on all supported frequencies of each transport supported rat until it finds a suitable cell. The main requirement for cell selection is that it should not take too much time that becomes more difficult with the growing number of frequencies and rats to be searched. The … Read more
Here I write on How Inter-RAT Mobility performs in LTE, means Handover to LTE and Mobility from LTE. Handover to LTE Procedure for handover of LTE is largely the same as the handover procedure in LTE. The main difference is that the handover to LTE AS a whole-configuration must be signaled, and the LTE it … Read more
Here I write about a simulation analysis of the system performance deterioration caused by the following four types of interference: eNodeB->UE, UE->eNodeB, eNodeB->eNodeB, and UE->UE when two systems share the eNodeBs. During simulation, it is assumed that the time percentage of the interference occurrence is 100%, that is, interference is always there. From simulation result … Read more
Subscriber Types Subscriber Equipment may take different form factors. It may resemble alert 3G phones, or maybe a CPE device, or a device connected to a USB dongle or USB port. RF different features, such as different transmission power levels, different Receive diversity schemes, different antenna patterns and gains, it would need Appropriate to perform … Read more