Detailed Answer
FDD (Frequency Division Duplex) and TDD (Time Division Duplex) are duplex communication methods: FDD uses two different frequencies for transmit and receive, TDD uses the same frequency with time-division transmit/receive. Industrial remote controls are mostly one-way (transmitter → receiver), i.e., half-duplex or simplex communication, and do not involve strict duplexing. Some high-end models (XINGJIA) support two-way communication (control + status backhaul) using TDD time division. Understanding duplexing helps when selecting products with two-way monitoring features.
| FDD | Two frequencies for TX/RX |
| TDD | Same frequency, time division |
| Remote controls | Mostly simplex |
Note:Choose a model supporting two-way communication when you need status backhaul.