Frequency Alteration Built on an Electro-Optical Sampling SOA–MZI Using a Differential Modulation Schema

Abstract

In this paper, we present a real and simulated study of a frequency up mixing employing an electro-optical sampling semiconductor optical amplifier Mach–Zehnder interferometer (SOA–MZI) along with the differential modulation schema. The sampling signal is generated by an optical pulse clock (OPC) at a frequency of fs= 19.5 GHz. The quadratic phase shift keying (QPSK) signal at an intermediate frequency (IF) fIF is shifted to high frequencies nfs ± fIF at the SOA–MZI output. Using a simulator entitled Virtual Photonics Inc. (VPI), we generate sampled QPSK signals and analyze their merits during conversion gains and error vector magnitudes (EVMs). We conducted simulations of mixing in the SOA–MZI operating in a high-frequency band up to 195.5 GHz. The positive conversion gain is accomplished over the mixing frequencies. The EVM is used to evaluate the performance of the electro-optical sampling up-convertor. The EVM reaches 14% at a data rate of 5 Gbit/s at 195.5 GHz. During the experimental work, the results obtained in simulations are set side by side with the factual ones in the frequency range up to 59 GHz. Thus, the comparison between them confirms that they have approximately the same performance.

Terahertz Replica Generation of Ultra-High Data Rate Transmission in an Electro-Optical Semiconductor Optical Amplifier Mach–Zehnder Interferometer System

“…In both setups, an additional IF signal is introduced at the electrical terminal of SOA1. This configuration was originally established as part of the innovative differential modulation [28]. A comparative analysis between these methods is presented in Table 1, which substantiates that the differential modulation exhibits superior efficiency and quality, as evidenced by enhanced conversion gains and reduced EVMs, respectively.…”

“…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.…”

“…A comparative analysis between these methods is presented in Table 1, which substantiates that the differential modulation exhibits superior efficiency and quality, as evidenced by enhanced conversion gains and reduced EVMs, respectively. While acknowledging the groundbreaking achievement of implementing the standard modulation approach in the electro-optical SOA-MZI design for the first time, it is essential to highlight the major advantages it offers in comparison to the previously explored differential modulation method [20,23,28,33]. Firstly, standard modulation techniques are renowned for their simplicity and ease of implementation, making them particularly advantageous in scenarios where a straightforward system design is paramount.…”

“…As a result, changes in carrier density also modulate the photonic gain. The sampling and the IF or RF signals, requiring up-or down-conversion, can both be processed simultaneously on the same device [27,28].…”

“…In real-world experiments and simulations, we are exploring innovative electro-optical up-converters within the standard modulation structure of a SOA-MZI, which is an extension to our previous work [28] based on photonic differential SOA-MZI modulation. The central receptacle of the administered SOA-MZI is designed to allow the ingress of the sampling signal into the active area of SOA1, while the IF electric subcarrier controls the electric terminal of SOA1.…”