Rayleigh Distribution with Flower Pollination Algorithm based Channel Estimation in Orthogonal Frequency Division Multiplexing

Orthogonal Frequency Division Multiplexing (OFDM) is an extensively used transmission technique that enables feasible modulation and demodulation in communication systems.Channel Estimation (CE) is applied in channel conditions where time-varying features are essential.However, Inter-Symbol Interference (ISI) occurs in MOFDM and leads to inaccurate channel impulse response estimation due to multi-path propagation.Therefore, this research proposes a Rayleigh Distribution with Flower Pollination Algorithm (RDFPA) for pilot insertion in CE to reduce Normalized Mean Square Error (NMSE) in the OFDM system.Additionally, the RDFPA identifies optimal factors by exploring possible areas in the global search space with quick convergence.To encode and decode the signals, the Space-Time Block Code (STBC) is applied, which improves communication and enhances the signal's spatial diversity.The 16-quadrate Amplitude Modulation (16-QAM) is used for signal modulation and demodulation.The Additive White Gaussian Noise (AWGN) is applied to the transfer signal from the transmitter to the receiver.The Bit Error Rate (BER), NMSE, and Symbol Error Rate (SER) are used to evaluate the RDFPA performance in CE.The RDFPA achieved a lower NMSE of 0.510-1 for a Signal-to-Noise Ratio (SNR) of 10dB, which is better than the existing Tunicate Swarm Optimization (TSO).