OFDM is well-known for LiFi; however, it is still fresh advanced waveform for OCC. This post shares an implementation of 2D-OFDM for Screen-to-Camera communication system in which a massive number of display cells brings a great advantage for communication.
- A full journal version of this topic is available online at IEEE Access.
- MIMO-OFDM screen-camera
- MIMO channel with sub-channels consisting of subcarriers for reliable communication.
- Configurable size of Tx, with OFDM symbols based on experimentally verifying the channel in conjunction with the channel analysis
- The new design of Tx that jointly supports critical functionalities
- 360-degree rotation support.
- Asynchronous communication with frame rate variation support.
- Correction of perspective distortion.
- Complete system architecture and detailed implemental guidance.
- OFDM symbol creation and Tx post-processing (2D-cyclic prefix insertion and clipping processes).
- Scaling and DC-bias control.
- 2D pilots design and channel equalization.
- PHY frame format PPDU co-existent to 802.15 standards.
- Effective FEC.
- Comprehensive Rx processing and decoding guidance
- Specific decoding processes are given based on implemental results, significantly including
- Spatial downsampling and the correction of perspective distortion,
- Temporal downsampling to deal with frame rate variation, and
- Rotation correction
The transmitter design:
- The bolder area: to support the detection and extraction of the code.
- The rotation tracking corners: to determine the rotation.
- Clock cells at the surrounding of the code: to support the Rx determining the proper sampling ratio under the presence of perspectivedistortion.