11-02-2013, 04:17 PM
LTE architecture n basics Overview
LTE architecture.pdf (Size: 1.1 MB / Downloads: 28)
What is orthogonality……?
Orthogonality occurs when two things can vary independently, they are uncorrelated, or they are perpendicular.
In Telecommunication terminology
If you take two signals, multiply them together and then
integrate over some interval, and the result is zero, then
they are orthogonal in that interval.
Benefits of using ofdma
Is easier to implement digitally due to DFT / FFT.
Has efficient bandwidth utilization. Subcarriers are put closeby & overlap but are orthogonal. (Reduced ISI).
Has good diversity due to the parallel transmission.
Is robust to multipath fading due to cyclic prefix.
Provides resource allocation flexibility. (A wideband channel is split into many subchannels.