This paper presents a secure communication scheme using real-time synchronization of multiple fractional-order chaotic systems (FOCS). The method employs a Step-By-Step Sliding-Mode Observer (SBS-SMO) for synchronization and an artificial Harris hawks optimization (HHO) algorithm to optimize the observer's parameters. The scheme successfully recovers secret messages (signal, voice, etc.) from the receiver portion of the system within a short time. Experimental validation was conducted using an Arduino microcontroller and electronic components, with results showing good agreement with theoretical calculations. The transmitter system is modeled using fractional-order differential equations, with secret information injected into the third derivative of the chaotic system. The receiver system is designed to synchronize with the transmitter using the SBS-SMO, which estimates the state variables and the secret message. The HHO algorithm is used to determine the optimal parameters for the SBS-SMO, ensuring effective synchronization and message recovery. The proposed method demonstrates the effectiveness of fractional-order chaotic systems in secure communication, leveraging their complex behavior and sensitivity to initial conditions. The system's security is enhanced by the use of fractional orders and initial conditions, which are critical for the synchronization process. The results show that the proposed scheme can recover secret messages with high accuracy, even in the presence of noise and disturbances. The study also highlights the practical implementation of the proposed method, including the use of Rung Kutta 4 for memory allocation in the microcontroller and the addition of capacitors to improve the performance of the NRF24L01 module. The results confirm the validity of the proposed secure communication scheme from both mathematical and numerical perspectives, demonstrating its potential for real-world applications.This paper presents a secure communication scheme using real-time synchronization of multiple fractional-order chaotic systems (FOCS). The method employs a Step-By-Step Sliding-Mode Observer (SBS-SMO) for synchronization and an artificial Harris hawks optimization (HHO) algorithm to optimize the observer's parameters. The scheme successfully recovers secret messages (signal, voice, etc.) from the receiver portion of the system within a short time. Experimental validation was conducted using an Arduino microcontroller and electronic components, with results showing good agreement with theoretical calculations. The transmitter system is modeled using fractional-order differential equations, with secret information injected into the third derivative of the chaotic system. The receiver system is designed to synchronize with the transmitter using the SBS-SMO, which estimates the state variables and the secret message. The HHO algorithm is used to determine the optimal parameters for the SBS-SMO, ensuring effective synchronization and message recovery. The proposed method demonstrates the effectiveness of fractional-order chaotic systems in secure communication, leveraging their complex behavior and sensitivity to initial conditions. The system's security is enhanced by the use of fractional orders and initial conditions, which are critical for the synchronization process. The results show that the proposed scheme can recover secret messages with high accuracy, even in the presence of noise and disturbances. The study also highlights the practical implementation of the proposed method, including the use of Rung Kutta 4 for memory allocation in the microcontroller and the addition of capacitors to improve the performance of the NRF24L01 module. The results confirm the validity of the proposed secure communication scheme from both mathematical and numerical perspectives, demonstrating its potential for real-world applications.