LTE

Here we discus about LTE Technology, detail on 4G and How to LTE.


Difference between DL and UL in LTE

what is main Difference between DL and UL in LTE ? OFDMA Advantages Robust against narrow-band co-channel interference Robust against Intersymbol interference (ISI) and fading High spectral efficiency Efficient implementation

OFDMA Transmitter in LTE

How OFDMA Transmitter in LTE ? In the downlink, OFDM is selected to efficiently meet E-UTRA performance requirements. With OFDM,  it is straightforward to exploit frequency selectivity of the multi-path

Cyclic Prefix problem in LTE

The problem is fixed by adding a guard time between each symbol to avoid the ISI. The ISI is still present but is not disturbing for the receiver. Principle :

Inter-Symbol Interference in LTE

What is the multipath? Due to the signal propagation phenomena, like reflection or diffraction, a receiver can receive several delayed versions of the same signal. This creates Inter-Symbol Interference (ISI).

LTE Sub-carrier

How Many Sub Carrier in LTE? Read below,..There are different kinds of sub-carriers: Data sub-carrier Pilot Sub-carrier DC sub-carrier Guard Sub-carrier DC stands for Direct Current and it is a

Notion of Orthogonality in LTE

In FDM, the sub-carriers are separated in the frequency domain to avoid interference between the sub-channels It results in a loss of spectrum efficiency because the frequency guard band can

OFDMA Principles in LTE

There are several ways to transmit over the frequency band and to share the resource between several devices.   What is TDMA,CDMA & FDMA ?   1.TDMA • The users

Constellation in LTE

The QPSK is the most robust modulation. It can be represented by a constellation: The radius, R, represents the amplitude. The angle, ?, represents the phase. There are 1 amplitude

Modulation in LTE

The 3G LTE uses 3 Quadrature Amplitude Modulations (QAMs) depending on the radio quality. QAM uses both the amplitude and the phase. The LTE supports in DL and UL the

LTE Architecture

Long Term Evolution (LTE) is the newest 3GPP standard for mobile network technology. The goal of the System Architecture Evolution (SAE) effort in 3GPP is to develop a framework for

LTE RF Link Budget

In any two-way radio system, the radio pathlosses and the equipment output powers and sensitivities must be taken into account for both directions. This is especially true in a mobile

RF Link Budget Gains & Losses

The system designer will need to determine the specific RF link budget parameters to be used when designing the system. The following figure shows the typical gains and losses that