학술논문

Multirate Optical CDMA Systems Combining Generalized Modified Prime Sequence Code and Bi-Orthogonal Code
Document Type
Periodical
Source
IEEE Access Access, IEEE. 12:56789-56798 2024
Subject
Aerospace
Bioengineering
Communication, Networking and Broadcast Technologies
Components, Circuits, Devices and Systems
Computing and Processing
Engineered Materials, Dielectrics and Plasmas
Engineering Profession
Fields, Waves and Electromagnetics
General Topics for Engineers
Geoscience
Nuclear Engineering
Photonics and Electrooptics
Power, Energy and Industry Applications
Robotics and Control Systems
Signal Processing and Analysis
Transportation
Codes
Adaptive optics
Multiaccess communication
Visible light communication
Optical transmitters
Optical receivers
Internet of Things
Bi-orthogonal code
generalized modified prime sequence code
multirate transmission
optical code division multiple access
visible light communication
Language
ISSN
2169-3536
Abstract
Recently, visible light communications (VLCs) have attracted attention as a complement to wireless communications by radio frequency. In addition, the demand for Internet of Things (IoT) communications has increased in the last decade, and VLC-based IoT systems are being considered. Because IoT devices operate at various data rates, multirate transmission is required. Herein, we propose a scheme that supports multirate data transmission for synchronous optical code division multiple access systems. This scheme employs a generalized modified prime sequence code and multiple extended bi-orthogonal codes. The proposed scheme realizes multirate transmission with an arbitrary number of data rate levels by superimposing spreading codes of different codelengths. In addition, the proposed scheme eliminates not only interference between users with the same data rate, but also interference between users with different data rates. Furthermore, we investigated the bit error rate performance and energy efficiency of the proposed scheme, considering the effects of background light, dark current, and PIN photodiode noise including shot noise, and thermal noise.