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Passive Backscatter Communication Scheme for OFDM-IM with Dynamic Carrier Activation
1College of Oceanography and Space Informatics, China University of Petroleum (East China), Qingdao 266580, China.
Sensors (Basel, Switzerland)
|April 28, 2023
Summary
This study introduces a dynamic subcarrier activated scheme for orthogonal frequency division multiplexing (OFDM) backscattering. It enhances communication distance and spectral efficiency for passive devices with limited power.
Area of Science:
- Wireless communication
- Signal processing
- Energy harvesting
Background:
- Multicarrier backscattering offers high communication rates but suffers from high power consumption.
- Complex circuits in multicarrier devices limit communication range, especially for distant passive devices.
- Insufficient power for backscatter devices hinders reliable communication.
Purpose of the Study:
- To propose a dynamic subcarrier activated scheme for orthogonal frequency division multiplexing (OFDM) backscattering.
- To improve communication range and spectral efficiency for passive backscattering devices with limited power.
- To reduce the power threshold required for device activation.
Main Methods:
- Introducing carrier index modulation (IM) into OFDM backscattering.
- Developing a dynamic subcarrier activation strategy based on collected power levels.
- Utilizing a block-wise combined index mapping with a look-up table for information transmission.
Main Results:
- The proposed scheme effectively increases communication distance for passive backscattering devices.
- Spectral efficiency is improved, particularly for low-order modulation schemes.
- Reduced power consumption allows devices farther from the RF source to maintain communication.
Conclusions:
- The dynamic subcarrier activated OFDM-IM scheme addresses power limitations in passive backscattering.
- This approach enhances the viability of backscattering communication in scenarios with limited energy.
- The method offers a practical solution for extending the range and performance of low-power wireless devices.
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