For channel estimation different types of reference signals are in use: – Cell specific reference signals. – MBSFN reference signals. – UE specific reference signals CELL-SPECIFIC REFERENCE SIGNALS These signals
The eNodeB determines the downlink transmit energy per resource element (lte epre). Downlink cell-specific reference-signal (RS) lte epre is constant across the downlink system bandwidth and constant across all subframes until
The uplink DPDCH and DPCCH are I/Q code multiplexed. But the downlink DPDCH and DPCCH is time multiplexed. This is main difference. Basically, there are two types of downlink DPCH.
Power control is essential for the smooth operation of a cdma system. Because all users share the same rf band through the use of pn codes Each user looks like random
The LTE link budget tool support the analysis for DL Traffic, UL Traffic, as well as signaling channel. Then the smallest radius is used as the final coverage radius based
Rake Receiver Instead of trying to overpower or correct multipath problems, CDMA takes advantage of the multipath to improve reception quality in fading conditions. CDMA does this by using multiple
lets talk about LTE Architecture- SERVICE, EPC, E-UTRAN and User Equipment. In the LTE network is divided into 2 basic networks, namely: 1. EUTRAN (Evolved Universal Terrestrial Radio Access Network) 2.
A 5-bit “modulation and coding scheme” yields the modulation order, i.e. QPSK, 16QAM or 64QAM. Implicitly the coding rate is given by a combination of the number of scheduled RBs
EPC ( Evolved Universal Terrestrial Radio Access Network) Functionally the EPC is equivalent to the packet switched domain of the existing 3GPP networks. EPC consist of:–MME (Mobility Management Entity)–SAE GW
Peak data rate 100Mbps (DL) and 50Mbps (UL) to 20MHz Throughput increased by 3-4 times and 2-3 times for the downlink to uplink from HSDPA Rel6 (DL=14.4Mbps, to use transmitter
Less complex modulation. OFDM is a simpler modulation technique that is better suited to deployments that do not require support for mobility. License-exempt bands. Mobile services require licensed spectrum to