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Numerical study of the performance improvement of the APSK transmission system using zero-nulling method
Hidenori Taga1, Jyun-Yi Wu, Wei-Tong Shih
1National Sun Yat-Sen University, No.70 Lien-Hai Road, Kaohsiung 80424 Taiwan ROC. hidenoritaga@mail.nsysu.edu.tw
Optics Express
|June 4, 2008
Summary
This study theoretically analyzes amplitude and phase shift keying (APSK) transmission. It evaluates the zero-nulling method
Area of Science:
- Optical Communications
- Digital Signal Processing
Background:
- Amplitude and Phase Shift Keying (APSK) is a modulation format with a trade-off between Amplitude Shift Keying (ASK) and Phase Shift Keying (PSK) performance, influenced by the ASK extinction ratio.
- The zero-nulling method has been proposed to enhance PSK performance, but it can reduce total system capacity.
Purpose of the Study:
- To theoretically investigate the transmission performance of APSK formats.
- To evaluate the effectiveness of the zero-nulling method in improving PSK performance under identical total system capacity.
Main Methods:
- Theoretical analysis of APSK transmission performance.
- Comparative study of modulation techniques considering extinction ratio and zero-nulling impact.
Main Results:
- The study quantifies the effectiveness of the zero-nulling method in enhancing PSK performance.
- Identified the conditions under which the zero-nulling method is beneficial without compromising total system capacity.
Conclusions:
- The zero-nulling method can be effectively employed to improve PSK performance in APSK systems.
- Maintaining identical total system capacity is crucial when implementing the zero-nulling method for optimal results.
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