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How does SC-FDMA work?

How does SC-FDMA work?

SC-FDMA is a hybrid modulation scheme that combines the low peak-to-average ratio (PAR) of traditional single-carrier formats such as GSM with the multipath resistance and in-channel frequency scheduling flexibility of orthogonal frequency-division multiplexing (OFDM).

What is SC-FDMA in wireless communication?

Single-carrier FDMA (SC-FDMA) is a frequency-division multiple access scheme. It is also called linearly precoded OFDMA (LP-OFDMA). Like other multiple access schemes (TDMA, FDMA, CDMA, OFDMA), it deals with the assignment of multiple users to a shared communication resource.

Why SC-FDMA is single carrier?

SC-FDMA (Singe Carrier FDMA) presents the benefit of a single carrier multiplexing of having a lower Peak-to-average Power Ratio. On SC-FDMA before applying the IFFT the symbols are pre coded by a DFT (Discrete Fourier Transform). This way each subcarrier after de IFFT will contain part of each symbol.

Why SC-FDMA is used in uplink?

Single-carrier frequency division multiple access (SC-FDMA) is common choice for uplink of long term evolution (LTE) standard for broadband wireless communication. SC-FDMA is preferred for LTE uplink mainly due to its advantage of having low peak-to-average power ratio (PAPR) during signal transmission.

What is the advantage of SC-FDMA?

SC-FDMA offers similar performance and complexity as OFDM. However, the main advantage of SC-FDMA is the low PAPR (peak-average-power ratio) of the transmit signal.

What is OFDM and SC-FDMA in LTE?

One of the key elements of LTE is the use of OFDM (Orthogonal Frequency Division Multiplex) as the signal bearer, as well as OFDM’s associated access schemes, OFDMA (Orthogonal Frequency Division Multiple Access) and SC-FDMA (Single Carrier Frequency Division Multiple Access).

How does SC-FDMA differ from OFDMA?

From the figure it is imperative that OFDMA is multi-carrier system with one data symbol carried over by one subcarrier; while SC-FDMA is a single carrier system where in each qpsk symbol is carried by one much wider bandwidth subcarrier.

Why LTE uses OFDMA for DL and SC-FDMA for UL?

Unfortunately OFDM has a high peak to average ratio. While this is not a problem for the base station where power is not a particular problem, it is unacceptable for the mobile. As a result, LTE uses a modulation scheme known as SC-FDMA – Single Carrier Frequency Division Multiplex which is a hybrid format.

How does SC-FDMA differ from FDM?

SC-FDMA system usually will have low PAPR compare to OFDM system. SC-FDMA system is less sensitive to frequency offset compare to OFDM system. SC-FDMA is widely used in LTE subscriber terminals in the transmit path and its variant OFDMA is used in the eNodeB downlink(or receive path of LTE subscribers).

What is SC-FDMA and how is it different from OFDM?

SC-FDMA is widely used in LTE subscriber terminals in the transmit path and its variant OFDMA is used in the eNodeB downlink(or receive path of LTE subscribers). While OFDM is used in many broadband technologies such as wimax-16d/16e, WLAN-11a/11n/11ac. OFDM is referred as multicarrier modulation.

How does SC-FDMA differ from OFDM?

What is FDMA full form?

FDMA is the most basic way of creating channels, by assigning users to nonoverlapping frequency bands, it was used in first and 2G cellular systems.