Sampling rate influence in up and down mixing of QPSK and OFDM signals using an SOA‐MZI in a differential configuration

Abstract

Up and down frequency conversions in the range of 0.5-39.5 GHz are performed by using a Semiconductor Optical Amplifier-Mach-Zehnder interferometer (SOA-MZI) in a differential configuration as a sampling mixer. The authors show that increasing the sampling frequency by a ratio of 2.5 (from 7.8 to 19.5 GHz) improves the efficiency and the quality of the optical transmission of QPSK and OFDM signals due to a better signal level and a lower aliased noise power when the sampling rate is higher. At the high sampling rate, the obtained EVM is sufficiently low for allowing data bit rates higher than 1 Gbit/s and 245 Mbit/s, respectively, for QPSK and OFDM modulated data.

Repetition rate performance for frequency mixing of four simultaneous QPSK signals based on a SOA-MZI photonic sampling mixer

“…As a result, we have built the same setup as the experimental work. 11,13 The genuine SOA-MZI used in simulation by the VPI simulator is displayed in Fig. 3.…”

“…As a result, we have used the same SOA-MZI (structure, static, and dynamic characteristics) built in a VPI simulator as the real device from CIP (40G-2R2-ORP). 11,13 The IF signals are created using laser sources, optical Mach-Zehnder modulators (MZMs), and optical attenuators (OAtts), respectively. The generation and detection module at the electrical port of the MZMs is used to produce the QPSK data.…”

“…The advantages of using this configuration to augment the sampling frequency are studied in our previous work. 13 By increasing the sampling frequency, the highest mixing frequency, which is the target frequency of the up converted signals, is related to different n of the sampling signal. For every channel, the up conversion obtained at the highest mixing frequency related to H 10 ¼ 10f s1 with f s1 ¼ 7.8 GHz can be also obtained with H 8 ¼ 8f s2 , H 6 ¼ 6f s3 , and H 4 ¼ 4f s4 with f s2 ¼ 9.75 GHz, f s3 ¼ 13 GHz, and f s4 ¼ 19.5 GHz, respectively.…”

“…Hence, we have used the same characteristics of the SOA-MZI performed in a VPI simulator as the real device from CIP (40G-2R2-ORP). 11,13 The simultaneous up conversion system is used to achieve better quality and efficiency of the optical transmission system in comparison with the SOA-MZI for up conversion of a single IF signal. 11,13 In other words, we can demodulate the signal through the EVM with a variety of bit rates (BRs) at a higher mixing frequency compared with the experimental work.…”

“…11,13 The simultaneous up conversion system is used to achieve better quality and efficiency of the optical transmission system in comparison with the SOA-MZI for up conversion of a single IF signal. 11,13 In other words, we can demodulate the signal through the EVM with a variety of bit rates (BRs) at a higher mixing frequency compared with the experimental work. Hence, in simultaneous up conversion, four IF signals are frequency up converted at nf sk AE f m at the SOA-MZI output.…”