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A New LoRa-like Transceiver Suited for LEO Satellite Communications
Mohamed Amine Ben Temim1, Guillaume Ferré1, Romain Tajan1
1IMS, University of Bordeaux, Bordeaux INP, CNRS UMR 5218, F-33400 Talence, France.
Sensors (Basel, Switzerland)
|March 10, 2022
Summary
This study introduces differential chirp spread spectrum (DCSS) to improve LoRa communication. The new method enhances synchronization, enabling reliable long-range IoT and satellite data transmission.
Area of Science:
- Wireless communication
- Signal processing
- Internet of Things (IoT)
Background:
- LoRa utilizes chirp spread spectrum (CSS) modulation for low-power, long-range IoT.
- LoRa signal decoding is highly sensitive to synchronization errors.
- Existing LoRa receivers have limitations on carrier frequency offset.
Purpose of the Study:
- To propose a modified LoRa physical layer, differential CSS (DCSS), to overcome synchronization challenges.
- To develop an original synchronization algorithm for DCSS.
- To enable robust communication for applications like low-Earth orbit (LEO) satellites.
Main Methods:
- Modification of the LoRa physical layer to introduce differential chirp spread spectrum (DCSS).
- Development and implementation of a novel synchronization algorithm tailored for DCSS.
- Demodulation of received signals with relaxed frequency and timing synchronization requirements.
Main Results:
- DCSS allows signal demodulation without complete frequency synchronization.
- The proposed method tolerates timing synchronization errors effectively.
- The receiver handles ultra-narrowband signals with no maximum carrier frequency offset limitation.
- DCSS demonstrates superior performance over CSS in the presence of varying Doppler shifts.
Conclusions:
- DCSS offers a robust solution for LoRa signal synchronization, mitigating sensitivity to errors.
- The proposed receiver is suitable for challenging communication environments, including LEO satellite links.
- DCSS enhances the applicability of LoRa-like technologies in demanding IoT scenarios.
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