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5G Millimeter Wave Frame Structure Overview

5g
mmwave
frame structure
tdd
wireless communication

This page provides an overview of the 5G millimeter wave (mmWave) frame structure, focusing on the dynamic Time Division Duplex (TDD) frame utilized in 5G mmWave systems.

The 5G mmWave frame structure is designed to facilitate both downlink (eNB to UE) and uplink (UE to eNB) communication, using control and data sections. This radio frame structure dictates how 5G eNBs and UEs relay transmissions over the air interface.

The figure below illustrates a single subframe, which repeats throughout the duration of a single 5G radio frame. Therefore, a 5G radio frame will contain multiple such subframes.

5G millimeter wave frame structure 5G millimeter wave frame structure

5G millimeter wave frames operate using TDD. TDD stands for Time Division Duplex.

Key characteristics of the 5G mmWave frame:

  • Frame Duration: Approximately 10ms.

  • Subframes: The frame is divided into smaller subframes, each lasting 1ms.

  • OFDMA Symbols: Each subframe consists of OFDMA symbols.

  • Time Division: Downlink (eNB to UEs) and uplink (UEs to eNB) transmissions are allocated different time slots within the subframe.

  • Frequency Reuse: Both downlink and uplink utilize the same RF frequencies in TDD, but at different time slots.

  • Guard Period (GP): A guard period or gap is inserted between different parts of the subframe to mitigate interference.

  • Subframe Components: The subframe is divided into reference, control, and data parts.

    • Reference Signals: These are included in each subframe to facilitate demodulation of downlink and uplink data.
    • Control Part: This section carries messages for connection establishment and management between the eNB and UE.
    • Data Part: This section carries the actual data payload, based on the application being used by various UEs in the 5G system.

  • Directionality: Subframes can be downlink-only (DL only), uplink-only (UL only), or bidirectional, supporting both UE and eNB communication.

Note: This frame structure is a proposed design. Always read latest 5G specifications from 3GPP and related websites for the most up-to-date information: