In addition to the traveling wave approach, a numerical solution for the enhanced time-delay rate equation model by assigning arbitrary lengths to the external cavities will be introduced [13; 14; 15]. Using very fine time integration in combination with a long integration time interval of several microseconds will result in a stable solution. With the help of this solution, we will study the operational aspects, dynamic behavior, and noise characteristics of the semiconductor laser further. This exploration will involve categorizing these features based on the bifurcation diagram (BD) of the output power of the LD and the RIN power spectrum in the laser signal [16]. The dynamics of the laser under double OFB are characterized using various tools, including the time variations of the emitted photons and RIN. Our investigation will span various values of external OFB strengths originating from double external cavities, along with variations in their distance from the laser's facet. We aim to identify the optimal conditions that result in stable laser operation with low noise for use in optical fiber communications. Additionally, we will identify the conditions that lead to chaotic dynamics, where the RIN spectrum does not reveal information about the laser system. This chaotic behavior holds potential significance in the realm of secure optical data encryption. Another application of our research is to better understand certain feedback processes and the resulting feedback noise, as these are the main limitations of Fiber-To-The-Home (FTTH) systems--for instance, to propose noise reduction solutionswithout the need for expensive optical isolators [17]. Using feedback control can involve adjusting the laser parameters or using them to minimize the impact of the feedback on system performance. In addition, optical attenuators can reduce the power of the feedback signal, which can help in reducing its impact on the laser, and the application of anti-reflective coatings to optical components can reduce the amount of reflection within the optical system, thereby minimizing the potential for feedback. The results of this work have a high impact on researching these topics further. Our improved model of double OFB can be used with LDs operating in single and multi-longitudinal modes, including various types of LDs. We categorize the laser's behavior based on output power and RIN power spectrum, considering two distinct external cavity lengths and optical phase due to OFB [18]. We present an investigation of the dynamic states and RIN of LDs subject to double OFB. We used modified and improved time delay rate equations for the LDs to consider double external OFB [12]. The dynamic states and noise of the LDs will be determined using the output photon number BD, its temporal variations, and the RIN of the LD with OFB strengths from the double OFB, as well as their spacing from the laser facet and with and without optical phase due to OFB. The LD dynamics are studied within two regions: short and long double external cavities. The simulated results show that the single OFB LD changes its state from continuous wave (CW) to periodic oscillation (PO), period doubling (PD), coherence collapse, and chaotic operation. In a short double external cavity region, LD draws from each of the operations with the single OFB to a route-to-CW state. This route-to-CW state is a reflection of the identical route-from-chaos to the identical operation with a single OFB. In a long double OFB regime, increased double OFB strength takes the LD to a route-to-chaos. In comparison with a single OFB case, the double OFB external cavity produces smoother, more chaotic RIN power spectra, which have no specific relationship with the resonance frequencies of the external cavities. Considering optical phase due to OFB in single OFB and double OFB cavities causes significant intensity suppression and phase shift in the temporal photon output of the LD changes.