5G NTN Helps to Build Satellite-Ground Converged Network II

IoT-NTN and NR-NTN

3GPP is actively exploring the concept of NTN with a focus on developing IoT-NTN and NR-NTN. These initiatives involve leveraging the foundation of NB-IoT/eMTC for IoT-NTN and building upon the advancements of 5G NR for NR-NTN for different application scenarios.

To implement 5G NTN, there are two architectures: 3GPP Rel.17 Bent-pipe architecture (Transparent mode) and Rel.18 Regenerative architecture (Regenerative mode). The standards work reflects this split. IoT-NTN is ideal for messaging since it is designed for low data rate connections, while NR-NTN allows for higher data rates that can support video calls and other applications.

?

Transparent/Bent-pipe mode:

Transparent satellites repeat the NR-Uu radio interface between the feeder link (NTN gateway to the satellite) and the service link (satellite to the UE). The NR-Uu interface serves as the communication channel for transmitting data and signals. Transparent satellites primarily focus on relaying communication between the NTN gateway and the UE, without the need for inter-satellite connections.

?

Regenerative mode:

Regenerative satellites implement signal regeneration of the received signals from Earth. They actively process and enhance the signals before retransmitting them, ensuring improved quality and reliability. The NR-Uu radio interface on the service link between the UE and the satellite.

?

Transparent/Bent-pipe mode

Regenerative mode

IoT-NTN eNB Software Functions and Description

IoT-NTN protocol stack has been categorized into user leveling and control plane. In user-plane IoT-NTN protocol multi consists of physical layer (PHY), MAC layer, RLC layer also PDCP layer. In Control-plane IoT-NTN protocol stack consists of PHY, MAC, RLC, PDCP, RRC and NAS layers.

?

eNB L1 FPGA-baseband Software

4??PHY Layer

ALifecom IoT-NTN eNB PHY ensures reliable transmission and reception of wireless signals. It supports narrowband channels with a bandwidth of 200 KHz, enabling efficient spectrum utilization. The PHY layer utilizes QPSK modulation for both downlink and uplink transmissions, maximizing spectral efficiency and signal robustness. And employs Orthogonal Frequency Division Multiple Access (OFDMA) in the downlink and Single Carrier Frequency Division Multiple Access (SC-FDMA) in the uplink, facilitating efficient resource allocation and power-saving capabilities.

?

eNB Radio Protocol Software

4??MAC Layer

The MAC layer provides efficient access control and scheduling functions for radio resources. It ensures optimal resource utilization, enabling simultaneous communication with multiple user devices. The MAC layer supports different classes of service, allowing for differentiated quality of service (QoS) based on application requirements.

4??RLC Layer

The RLC layer ensures reliable transmission of data packets. It handles segmentation, reassembly, and error detection for seamless and error-free data transfer. The RLC layer employs advanced techniques for efficient bandwidth utilization and reduced latency.

4??PDCP Layer

The PDCP layer optimizes the transmission of IP packets by providing header compression and encryption. It reduces the overhead associated with packet transmission, enhancing the overall efficiency of data transfer. The PDCP layer ensures secure communication by implementing encryption and integrity protection mechanisms.

4??RRC Layer

The RRC layer handles control signaling and connection management between the user devices and the core network elements. It manages procedures such as device registration, mobility management, and power-saving features. The RRC layer ensures seamless handover, network attachment/detachment, and efficient utilization of network resources.

4??RRM Layer

RRM optimizes the allocation and utilization of radio resources, and ensures efficient load balancing, interference management, and quality of service (QoS) control.

ALifecom Technology Coporation

#ALifecom?is a leading provider of wireless communication signal testing solutions, specializing in network testing solutions for top industrial and consumer electronics manufacturers worldwide. With multiple core technology patents, we are committed to delivering industry-leading mobile network testing solutions for cell phones, designed to serve top industrial and consumer electronics manufacturers globally.

We have focused on researching and developing advanced wireless communication technology for many years. Our research and development team has accumulated extensive technical expertise in various wireless communication technologies, including 5G NTN, WiFi, DVB-T, WiMax, g.hn, 4G LTE/LTE-A, eMTC, NBIoT, small cell, and the latest 5G NR technology, focusing on wireless communication technology related?to the terminal and base station (including base station and core network) of cellular mobile networks.

Contact us at?[email protected]