## 2 Electro-Optical Basic Concept of Architectural Standard Modulation
### Optical Conversion Gain Features  
The terminus of the photonic SOA-MZI defines the outbound photonic power for the up-mixed field, determined by the applied electro-optical standard modulation design, and quantified at 29.5 dBm through precise measurement with a power meter (PM). The optical conversion gain (OCG) of the up-lifted signal is determined by the difference between the outgoing mixed power of 29.5 dBm and the inlet data power of \(-15\) dBm. In consequence, the electro-optical classical modulation technology can be assessed with an OCG number of 44.5 dB, which is efficiently considered a valuable outcome. It is important to highlight that the OCG holds a similar value in both the experimental and simulated investigations. In our experimental or simulated arrangement, it is feasible to measure only a single output optical power value along with the optical input power using a PM. In such instances, a singular value for the OCG is obtained. Various approaches can be employed to assess the mixing system's performance for optimal results. Initially, the optical input power of the data signal is adjusted within the range of \(-30\) to 15 dBm, establishing that the most favorable OCG outcome occurs at \(-15\) dBm, as depicted in Figure 3 for the experimental and simulated results. Furthermore, adopting the standard modulation configuration with the OBPF set at 1550 nm, corresponding to the OPC wavelength, significantly enhances system quality, as evidenced in Figure 3.  
Conversely, modifying the OBPF wavelength to 1545 nm, aligning with the data signal wavelength as shown in Figure 4, leads to a substantial 20 dB reduction in the OCG across the entire input power range for the experimental study. To address this issue, implementing the standard switching configuration, wherein the positions of the OPC and data signal are interchangeable, proves beneficial [30]. Consequently, the peak OCG of 44.5 dB is attained with an input optical power of \(-15\) dBm for the data signal, aligning with the OBPF set at 1550 nm. Figure 3: Experimental and simulated OPG as a function of the input optical power of the data signal. C. Electrical Conversion Gain Attributes  
In both the simulated and experimental investigations, we display the electrical spectra of the up-lifted signal at the outgoing of the SOA-MZI, as displayed in Figures 5 and 6, respectively. These results serve as evidence of the fundamental concept of the electro-optical standard modulation design. It is worth noting that the original input IF signals in both cases are up-converted at mixing frequencies \(nf_{s}\pm f_{IF}\). In these scenarios, the amplitude of the multiple harmonics of the sampling captured signal gradually decreases with the harmonic rank. The simulation results depicted in Figure 5 show an approximately 8 dB distinction from the initial to the tenth harmonic due to the dynamic nature of the SOA-MZI [20; 30; 45]; this phenomenon cannot be avoided. Notably, the up-converted transmissions include the tenth harmonic of the sampling signal. Therefore, \(10f_{s}+f_{IF}=195.5\) GHz represents the highest frequency range achieved in Figure 5.  
Figure 4: Experimental OPG as a function of the input optical power of the data signal when the OBPF is adjected at two different wavelengths. Figure 5: Electrical spectrum of the up-converted photon at mixing frequencies \(nf_{s}\pm f_{IF}\) at the SOA-MZI outgoing for the applied standard modulation. The frequency of the IF signal is \(f_{IF}=0.5\) GHz, the sampling control frequency is \(f_{s}=19.5\) GHz, and the sampling signal harmonics at \(H_{u}=nf_{s}\). The experimental exploration of the SOA-MZI standard modulation system is depicted in Figure 6, showcasing the representation of solely the initial three harmonics of the control signal alongside the replicas of the mixed signal. Consequently, the deterioration of the up-mixing replicas is fundamentally identical in both situations. In both cases, the up-converted signals track the control signal harmonics as they recede.