Terminology » IoT » LTE NB-IoT Channel Types: Downlink and Uplink

LTE NB-IoT Channel Types: Downlink and Uplink

lte nb-iot channel downlink uplink

This page dives into LTE NB-IoT channel types, outlining the signals and channels utilized in both downlink and uplink directions.

NB-IoT LTE Channel Types NB-IoT LTE Channel Types

  • LTE NB-IoT leverages physical signals and physical channels.
  • Physical signals facilitate system synchronization, cell identification, and channel estimation.
  • Physical channels are dedicated to transporting control information, scheduling data, and user payloads originating from higher layers.
  • NB-IoT employs OFDMA in the downlink and SC-FDMA in the uplink direction at the physical layer.
  • It supports both FDD and TDD modes of operation.

The image illustrates the signal and channel types used in LTE-NB (NB-IoT) technology for both downlink and uplink communication. Let’s break down each one:

  • NPSS: Narrowband Primary Synchronization Signal. This signal is crucial for initial cell search and synchronization.
  • NSSS: Narrowband Secondary Synchronization Signal. This signal helps with cell identification and frame timing.
  • NRS: Narrowband Reference Signal. Used for channel estimation, which is vital for demodulating downlink signals.
  • NPBCH: Narrowband Physical Broadcast Channel. Carries essential system information, allowing devices to access the network.
  • NPDCCH: Narrowband Physical Downlink Control Channel. Transports downlink control information, such as resource assignments for NPDSCH.
  • NPDSCH: Narrowband Physical Downlink Shared Channel. Used for transmitting user data and some system information.
  • DMRS: Demodulation Reference Signal. This uplink signal is used for channel estimation at the base station, facilitating proper demodulation of uplink data.
  • NPRACH: Narrowband Physical Random Access Channel. Allows devices to initiate communication with the network, often for initial access or after a period of inactivity.
  • NPUSCH: Narrowband Physical Uplink Shared Channel. Carries user data and control information from the device to the network.