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

Abstract

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 M-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.

Performance Analysis of Multi User Optical Wireless Network (IR, or UV light for signal carrying) under Different Environmental Conditions

“…Different rain attenuation circumstances are also used to compare the performance of different codes. The work [9] has been reported based on the bipolar OCDMA method based on SCA for optical-polarized creation and transmission. The suggested system utilizes a dual electrooptical modulator architecture, which boosts transmission speed above existing methods.…”

Performance Analysis of Bipolar Optical Code Division Multiple Access with Dual Electro-Optical Modulator Scheme for Free-Space Optical Communication

“…The performance measurement in the simulation implemented the bipolar OCDMA with dual EOM scheme proposed in our previous work [14]. The performance of bipolar OCDMA with dual EOM scheme increase the transmission rate compare to switch scheme [13].…”

“…Figure 3 displays the example when user send alternate bit of "0" and "1" will resulted in "-1" and "+1" signals in the receiver-end. To implement the signature codes with length N in the proposed schemes, the results of the following correlation must be obtained [14]:…”

“…The limitation in the optical switch speed caused the limitation in transmission rate of the system [13]. In our further work [14], a dual electro-optical modulator (EOM) was proposed to improve the transmission rate. The results verified the visibility of the proposed scheme.…”

Special Issue on Enabling Technology in Optical Fiber Communications: From Device, System to Networking

“…Regarding the system-level technologies for optical communication, Tseng, S. et al 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 [ 7 ]. The proposed free-space optics communication system used a dual electro-optical modulator design, which could improve the transmission rate.…”