## 2 Electro-Optical Basic Concept of Architectural Standard Modulation  
The design of the SOA-MZI utilized in our experimental observations and simulations is depicted in Figure 1. The simulated outcomes are achieved using a VPI emulator. A SOA-MZI mixing investigation based on the VPI application was originally introduced in our earlier research [30; 31]. In each arm of the MZI, there is a semiconductor optical amplifier (SOA). Both output arms benefit from phase stabilization achieved by incorporating a phase-shifting element situated in each arm's top section. To the best of our knowledge, Figure 1 is the first depiction of the operational principle of the SOA-MZI standard modulation design for electro-optical mixing. In previous work, we utilized the sampling technique to explain the up-conversion process; you can find more details in [20]. Additionally, our previous setup [28] elaborates on the methodology used in the electro-optical up-converter constructed with SOA-MZI employing differential modulation. In the standard modulation approach, the sampling signal, transmitted by an optical pulse clock (OPC) at a specific sampling frequency \(f_{s}\) and a wavelength \(\lambda_{s}\), undergoes splitting at the median port (MP) of the SOA-MZI into two identical copies. Furthermore, the spectral elements of the sampling captured signal experience upward conversion in conjunction with the intermediate-stage signal. Importantly, there is no constraint on the repetition rate being within the modulation bandwidth of the SOA-MZI, allowing operation at frequencies that are abundant, as required for MMW applications [32]. In recent work, we used a data acquisition rate of \(f_{s}=19.5\) GHz [23]. Consequently, as the sampling interval rises, the photonic transmission efficiency is significantly improved [33]. The intermediate frequency (IF) photon is applied to the SOA electrode, where it modulates the steady-state current (bias current) with a specific intermediate frequency, denoted as \(f_{IF}\), as shown in Figure 1. Quadrature Phase Shift Keying (QPSK) data can be transmitted over this electric subcarrier. This variation in the steady-state current leads to changes in the carrier density, allowing the IF signal to control the sampling signal immediately [20]. Since the optical gain of SOA1 is contingent on the carrier density, the enhanced sampling signal is continuously varied. This variation can be observed at the top and bottom ports, indicating that it is modified using the data channel. Consequently, the sampled signal exiting SOA1 and the amplified sampling captured signal from SOA2 are integrated at the terminal of the SOA-MZI. This is achieved following photonic filtering at the wavelength \(\lambda_{s}\) to generate the up-shifted photon. The resultant sampled photon contains frequency components of the sampling signal and is present at mixing frequencies \(nf_{s}\pm f_{IF}\), where \(n\) varies from 1 to 10. Electro-optical mixing, particularly when implemented using a SOA-MZI standard modulation, offers several compelling benefits compared to its all-optical counterpart [20; 23]. One significant advantage lies in its inherent compatibility with established electronic signal processing techniques, allowing seamless integration into existing electronic systems. The ability to convert optical signals to electrical ones facilitates the precise control and manipulation of the signals, enabling advanced modulation and signal shaping. This feature proves advantageous in applications where intricate signal processing, format conversion, or regeneration are essential. Additionally, electro-optical mixing provides a versatile platform, accommodating a wide range of modulation formats and enabling the exploitation of electronic technologies for real-time adaptive control. The incorporation of electronic components, though introducing some complexity, often results in improved signal quality and reliability.