2.4 – OFDMA/SC-FDMA IN 4G LTE – PART 2
OFDMA/SC-FDMA in 4G LTE – Part 2
Streams of data, in the form of bits, reaches network gateway from various sources. The Gateway forwards it to the eNodeB. But how does the eNodeB converts them into radio signals and transmit them to the user over the air interface? How does the user equipment communicate back with e Node B?
We have shown, how data is transmitted and mapped on resource element using different modulation scheme, serial to parallel converter and Resource mapping technique.
Further how it is inefficient to transmit data using 1200 Oscillator, so to overcome this we have introduce IFFT in OFDMA block diagram, which convert frequency domain to Time domain sample signal.
We have also describe, number of sample required for 1 subcarrier and 1200 subcarrier for 1 second and for 1 symbol with period of 66.7Microseconds. How Backward compatibility used in OFDMA for sampling rate.
How OFDMA is not suitable for UPLINK Direction due to Large PAPR, and how it is overcome by using SCFDMA and introduction of FFT block.
Enjoy the video.
HAPPY LEARNING
Reference:
Images – Google images, Openclipart,
Video – Norway (Rusted Media)
Music – Bensound, Google youtube audio library
Content – 1. LTE – The UMTS Long Term Evolution (From Theory to Practice – book)
2. LTE Advanced by Wiley Publication – Book
3. Wikipedia
4. LTE in Bullets
5. Other Internet Resource
4g lte
