What is SC?
SC (Single Carrier) is a transmission technique that uses a single radio frequency carrier to transmit all data, as opposed to multicarrier techniques (like OFDM) that distribute data across multiple parallel subcarriers. Single-carrier transmission has inherently lower PAPR than multicarrier, making it attractive for uplink transmission where UE power amplifier efficiency is critical. In 5G NR, DFT-s-OFDM is a single-carrier-like waveform option available for the uplink.
How Does SC Work?
In a single-carrier system, the entire channel bandwidth is used by one serial symbol stream. Each symbol occupies the full bandwidth for a short duration (symbol period = 1/bandwidth). This creates a single peak in the frequency domain, resulting in lower PAPR compared to OFDM where multiple subcarriers can add coherently. However, single-carrier transmission in a wideband frequency-selective channel requires complex time-domain equalization at the receiver (unlike OFDM where equalization is simplified to per-subcarrier scaling). DFT-s-OFDM in 5G NR bridges both worlds — it provides the PAPR advantage of single-carrier while using OFDM-style processing (IFFT/FFT) for efficient implementation and frequency-domain equalization.
Use Cases
5G NR uplink transmission using DFT-s-OFDM for coverage enhancement, power-limited UE scenarios, IoT and MTC uplink with power efficiency requirements, and cell-edge performance improvement using single-carrier waveforms.
3GPP / Standards Reference
3GPP TS 38.211 (NR — DFT-s-OFDM uplink), 3GPP TS 38.300 (NR waveform overview)
Related Terms
MC | OFDM | DFT-s-OFDM | PAPR | CP-OFDM
Learn More
This glossary entry is part of the 5GWorldPro Complete 5G Glossary. To go deeper into 5G architecture and technology, explore our 5G Training courses.
