5G • RAN

QPSK

Quadrature Phase Shift Keying

Robust modulation scheme mapping 2 bits per symbol, used for control channels and cell-edge conditions.

Technical Explanation

QPSK maps pairs of bits into four distinct phase constellation points. It provides high resilience against low signal-to-noise ratios (SINR), making it the universal modulation for PDCCH, PUCCH, PBCH, and cell-edge PDSCH/PUSCH data transmissions.

Key Functions

  • Maps 2 coded bits per complex modulation symbol
  • Serves as baseline modulation for all 5G control channels
  • Maintains connectivity under harsh negative SINR conditions
Specifications
3GPP TS 38.211
Interfaces
Uu

Related 5G Concepts

Want to memorize 5G concepts like this one?
Study it with SuperMemo SM-2 spaced repetition flashcards.
Practice 5G Flashcards