Differential Decoding of SIM DPSK over FSO MIMO Links

作者：Bhatnagar Manav R^*

来源：IEEE Communications Letters, 2013, 17(1): 79-82.

DOI：10.1109/LCOMM.2012.112012.121920

• Differential modulation
• free space optical links
• Gamma-Gamma fading
• multiple-input multiple-output (MIMO) system

In this paper, we derive a differential decoder for the subcarrier intensity modulation (SIM) based differential phase shift keying (DPSK) scheme in free space optical (FSO) multiple-input multiple-output (MIMO) communication system. The proposed differential decoder avoids requirement of the knowledge of irradiance fluctuations in the receiver contrary to the existing selection combining (SC) based decoder of SIM DPSK. Moreover, the proposed differential decoder enables the SIM DPSK scheme to outperform the non-coherent decoding based pulse position modulation scheme. We theoretically analyze the bit error rate (BER) performance of the SIM differential binary phase shift keying modulation scheme with differential decoding over FSO MIMO links which follow the Gamma-Gamma distribution. On the basis of the analytical BER, the analytical diversity order of the proposed differential decoder is obtained.

• 出版日期2013-1