Optimization of operating bandwidth and subcarrier transmit powers using partial pre-equalization for optical OFDM transmissions with IM/DD | |
| Author | Jariya Panta |
| Call Number | AIT Thesis no.TC-14-01 |
| Subject(s) | Orthogonal frequency division multiplexing Optical communications |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Telecommunications |
| Publisher | Asian Institute of Technology |
| Abstract | Orthogonal Frequency Division Multiplexing (OFDM) has been considered as an emerging modulation technique for high data rate transmissions in optical wireless communication (OWC). This thesis focuses on indoor OWC based on asymmetrically clipped optical OFDM (ACO-OFDM) transmission with intensity modulation and direct detection (IM/DD). To demonstrate its performances, ACO-OFDM transmissions through OWC channels are simulated and compared to DC-biased optical OFDM (DCO-OFDM) and flip-OFDM. The power efficiency of ACO-OFDM is verified to be better than DCO-OFDM, and to be the same as for flip-OFDM. The transmit optical power is then optimized through the proposed use of partial pre-equalization, which can reduce the required transmit optical power over post-equalization, and can be used in broadcast systems where pre-equalization is not applicable. Since not all subcarriers are used when OWC channels become dispersive, the utilized bandwidth, which corresponds to the transmission bit rate, is quantified and optimized by varying the number of transmitted bits per OFDM symbol. Moreover, to further improve power efficiency, bit loading algorithms are applied in these investigations. |
| Year | 2014 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Telecommunications (TC) |
| Chairperson(s) | Teerapat Sanguankotchakorn; |
| Examination Committee(s) | Poompat Saengudomlert;Keattisak Sripimanwat; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2014 |