Abstract / Description of output
An expression for the bit error rate of a multiple subcarrier intensity-modulated atmospheric optical communication system employing spatial diversity is derived. Spatial diversity is used to mitigate scintillation caused by atmospheric turbulence, which is assumed to obey log-normal distribution. Optimal but complex maximum ratio, equal gain combining (EGC) and relatively simple selection combining spatial diversity techniques in a clear atmosphere are considered. Each subcarrier is modulated using binary phase shift keying. Laser irradiance is subsequently modulated by a subcarrier signal, and a direct detection PIN receiver is employed (i.e. intensity modulation/direction detection). At a subcarrier level, coherent demodulation is used to extract the transmitted data/information. The performance of on-off-keying is also presented and compared with the subcarrier intensity modulation under the same atmospheric conditions.
Original language | English |
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Pages (from-to) | 16-23 |
Number of pages | 8 |
Journal | IET Optoelectronics |
Volume | 2 |
Issue number | 1 |
DOIs | |
Publication status | Published - Feb 2008 |