SC-FDMA

Single-Carrier Frequency Division Multiple Access (SC-FDMA) is a frequency division multiple access scheme that has gained popularity, particularly in long-term evolution (LTE) uplink communication. It is a method that allows multiple users to share a common communication channel by dividing the available bandwidth into multiple frequency sub-bands. The uniqueness of SC-FDMA lies in its use of a single carrier to transmit signals. This reduces the peak-to-average power ratio (PAPR) compared to other multiple access schemes, making it more power-efficient and ideal for uplink communication where mobile devices have limited power resources. In SC-FDMA, each user's signal is converted from time domain to frequency domain using Fast Fourier Transform (FFT). The signals are then allocated to different sub-bands based on the frequency-domain spreading. After this, the signals are converted back to time domain using Inverse Fast Fourier Transform (IFFT) before transmission. The use of SC-FDMA in LTE uplink communication offers several advantages, including reduced inter-symbol interference, improved power efficiency, and better frequency diversity. It also allows for flexible bandwidth allocation, which can be adjusted according to the user's data rate requirements.