Multi-modulation compatible miniaturization system for FSO communication assisted by chirp-managed laser

Abstract

In recent years, the thriving satellite laser communication industry has been severely hindered by the limitations of incompatible modulation formats and restricted Size Weight and Power (SWaP). A multi-modulation compatible method serving for free-space optical (FSO) communication has been proposed assisted by chirp-managed laser (CML). The corresponding demonstration system has been established for realizing free-switching between intensity (OOK) and phase modulation (RZ-DPSK). The feasibility and performance of system have been evaluated sufficiently when loading with 2.5 and 5 Gbps data streams, respectively. Additionally, a control-group system has been operated utilizing Mach-Zehnder modulator (MZM) for comparison between CML-based and MZM-based compatibility solutions. The OOK receiving sensitivities of CML-based system are −47.02 dBm@2.5 Gbps and −46.12 dBm@5 Gbps at BER of 1×10−3 which are 0.62 dB and 1.11 dB higher than that of MZM; the receiving sensitivities of RZ-DPSK are −50.12 dBm@2.5 Gbps and −47.03 dBm@5 Gbps which are 0.79 dB and 0.47 dB higher than that of MZM respectively. Meanwhile, CML-based transmitter abandoned the traditional modulator and its complicated supporting devices which can effectively contribute to the reduction of SWaP. The CML-based system has been proven to have the compatibility between intensity and phase modulation while also possesses a miniaturized design. It may provide fresh thinking to achieve a practical miniaturization system for satisfying the requirements of space optical network in future.

Enhancing recognition performance of vortex arrays through conditional generative adversarial network-based data augmentation

“…In Fig. 1(b), ðl x ; l y Þ are set as (2,6), (2,9), (3,5), (3,8), (4, 7), (5,6), (8,2), and (9, 1). To distinguish them, each array mode was labeled from VL1 to VL8.…”

“…Free-space optical communication (FSOC) holds a vital role in facilitating high-speed and long-distance communication, attributed to its advantages of requiring no frequency authorization, possessing a remarkable transmission bandwidth, and boasting low power cost 1 – 5 Mode division multiplexing has emerged as a promising technique of FSOC, enabling the fulfillment of high-capacity communication requirements 6 , 7 . Optical vortex beams are distinguished by their nonzero orbital angular momentum (OAM).…”

Research progress of chirp managed lasers

“…In order to suppress transient chirp, the bias voltage of DFB operation should be higher than the threshold, usually set at 5 times the threshold. The CML laser, combined with an OSR filter, can immediately perform spectral shaping on low extinction ratio intensity signals as soon as they are emitted through the filter, thus achieving high extinction ratio intensity modulation of the signal, as shown in Figure 1 [7] .…”