Time Division Duplex

TDD Time Division Duplex

Duplexing method to enable bidirectional (Uplink and Downlink) communication between devices

TDD uses the same frequency band for both uplink and downlink transmissions, but separates them by time slots.
At a given time, a device either transmits or receives. The direction switches rapidly so both directions appear nearly simultaneous to users.
Advantages:
- Flexible allocation of Uplink/Downlink capacity (e.g., more DL slots if needed).
- Better suited for scenarios with asymmetric data traffic.
- Spectrum efficiency in certain deployment models.
Used in many 5G NR and LTE networks, especially in unpaired spectrum (single frequency channel).
Example of TDD configuration in 5G: frame is divided into slots, and each slot is allocated as either DL, UL, or special (guard period).