Security in Spatially Correlated MIMO OSFBC OFDM Multicast System over Frequency Selective Fading Channel

Abstract

The system performance can be improved significantly by employing orthogonal space-frequency block coding (OSFBC) and orthogonal frequency division multiplexing (OFDM) because in this combination the receiver suffers lesser complexity. Recently, the wireless systems are deploying by the increasing number of closely spaced antennas. So the assumption of in-dependency among the antenna brunches is not valid. Realizing the advantages of this combination of system and taking account the effect of antenna correlation, this work demonstrates the insight of secured wireless multicasting network consisting multiple antennas both in transmitter and receiver over spatially correlated frequency selective fading channels. The desired signals have been protected from eavesdropping by useful impact of antenna diversity and antenna correlation. The main contribution of this work is the development of mathematical models of the probability of non-zero secrecy multicast capacity (PNSMC) and the secure outage probability for multicasting (SOPM) to secure the system from eavesdropping. The analytical results are verified via Monte-Carlo simulation to ensure the validity of the developed mathematical model. Moreover, the numerical analysis gives a clear indication that security in OSFBC OFDM system with antenna diversity over spatially correlated frequency selective fading channel upgrades due to the effect of transmit antenna correlation and degrades due to receive antenna correlation. But the loss of this security can be significantly reduced employing antenna diversity with OSFBC-OFDM systems.