Bipolar Optical Code Division Multiple Access Techniques Using a Dual Electro-Optical Modulator Implemented in Free-Space Optics Communications

• Published in: Sensors (Basel, Switzerland) Vol. 20; no. 12; p. 3583
• Main Authors: Tseng, Shin-Pin, Wijanto, Eddy, Lai, Po-Han, Cheng, Hsu-Chih
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 24.06.2020; MDPI
• Subjects: Bandwidths; bipolar; Code Division Multiple Access; Coding theory; Communication; Communications systems; electro-optical modulator; Free space optics; free-space optics communication; Internet of Things; optical code division multiple access; Optical communication; Subtraction; Systems design; Wave division multiplexing; Wireless communications; bipolar; free-space optics communication; electro-optical modulator; optical code division multiple access
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s20123583

This study developed a bipolar optical code division multiple access (Bi-OCDMA) technique based on spectral amplitude coding for the formation and transmission of optical-polarized and coded signals over wireless optical channels. Compared with conventional Bi-OCDMA schemes, the proposed free-space optics communication system that uses a dual electro-optical modulator design improves the transmission rate. In theory, multiple access interference can be removed by using correlation subtraction schemes. The experiment results revealed that the proposed system can be employed to accurately extract codewords from an -sequence and subsequently reconstruct the desired original data. Moreover, the proposed architecture can be implemented easily in simple and cost-effective designs and may be beneficial for broadening the use of Bi-OCDMA schemes in wireless optical communications.