Here we discuss about LTE Technology, details on 4G and How to LTE.
How Handover Filtering by UE in LTE ? If the IE “Filter coefficient” is received the UE applies filtering of the measurements for that measurement quantity according to the formula below. This filtering is performed by the UE before UE event evaluation. The UE filters also the measurements reported in the IE “Measured results”. The … Read more
Handover principles and Handover measurements in LTE 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 … Read more
What is AMC & its Algorithm in LTE The effective Eb/No and hence the spectral efficiency depend on BLER. However there are QoS requirements which also have to be considered. Taking both into account leads to a target BLER. AMC is in use in order to tune BLER so that the target value is reached. … Read more
UL and DL cell based scheduler The scheduling is performed on cell basis. The two main functions are to decide which UE(s) shall be scheduled, the number of resources and the MCS to be applied. Furthermore the scheduler needs to be QoS aware. There is priority given to random access responses, control data, HARQ retransmissions. … Read more
Scheduler types in LTE A variety of scheduling strategies is available in LTE. The scheduling strategy is based on a certain metric. – Round-Robin. No quality indication is taken into consideration. The resources are mainly shared in an equal manner. – Max C/I. The UE with the best channel conditions gets the highest priority. The … Read more
Scheduling Principle,Frequency and time domain in LTE Deployment of shared channels offers the possibility for scheduling. In this way information on varying channel conditions can be exploited to increase the overall throughput. Fast scheduling in time (1 ms) and frequency domain reduces latency and improves peak rate. Adaptive Modulation and Coding leads to higher data … Read more
Hybrid ARQ (HARQ) in LTE 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. … Read more
How CQI, PMI and RI reporting by UE in LTE? 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 … Read more
Modulation and TB size LTE Modulation Techniques In Long-Term Evolution (LTE) networks, modulation is a fundamental aspect of the physical layer responsible for encoding digital information into analog signals for transmission. LTE employs various modulation schemes to adapt to different channel conditions and maximize data rates. The primary modulation schemes used in LTE include: Quadrature … Read more
Based on DCI formats Resource allocation in LTE Based on DCI formats In LTE Three types of allocation are used: type 0: DCI formats 1, 2, 2A type 1: DCI formats 1, 2, 2A type 2: DCI formats1A, 1B, 1C, 1D One bit in the header is indicating if DCI formats 1, 2, 2A are … Read more