Performance evaluation of coherent free space optical communications with a double-stage fast-steering-mirror adaptive optics system depending on the Greenwood frequency

Liu, Wei; Yao, Kainan; Huang, Danian; Lin, Xudong; Wang, Liang; Lv, Yaowen

doi:10.1364/oe.24.013288

Cited by 73 publications

(23 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…17,18 The mixing efficiency and the BER performances of the closed-loop AO integrated with the coherent optical communications were analyzed. [19][20][21] Different AO approaches for OGS were presented and compared. 22 Although the AO was proven to be a very promising technique that can largely improve the performances of the space-to-ground optical communication links, the complex systems and expensive costs limit its application.…”

Section: Introductionmentioning

confidence: 99%

2.5- and 5-Gbps time-delay self-homodyne interference differential phase-shift keying optical receiver for space-to-ground communication link

et al. 2019

View full text Add to dashboard Cite

The availability and reliability of the high data rate space-to-ground optical coherent communication links are critically challenged because the wave front of the signal beam is distorted and impaired when propagating through atmospheric turbulence. Based on the free-space interference of two successive data bits delayed by an unequal-arm-length Mach-Zehnder interferometer (MZI), a pupil-matching time-delay self-homodyne interference differential phase-shift keying (DPSK) optical receiver with 2 × 4 90-deg optical hybrid is designed for the high data rate space-to-ground optical communication links due to its immunity from wave front impairment. The delayed optical path difference (OPD) in the unequal-arm-length MZI corresponds to the duration of one bit and can be stabilized to below 1000th of the wavelength by the closed-loop feedback control. The maximum system insertion loss is <1 dB. The measurement accuracy of OPD in unequal-armlength MZI is 0.01 mm by the deramping method from a chirped laser. The double-bit-rate 2.5-∕5-Gbps DPSK optical receiver has been presented. Parallel and separate atmospheric measurement along the optical communication link is also performed simultaneously. The 2.5-and 5-Gbps optical communication links have already been verified with a ϕ300-mm receiving telescope between two buildings in downtown over a distance of 2.4 km in the worst-case atmospheric conditions. The measured bit-error-rate is better than 10 −6 . Without wave front compensation of the adaptive optics, local oscillator, and optical phase-locked loops, the pupil-matching time-delay self-homodyne interference DPSK optical receiver has great significance for future developments of space-to-ground optical communication links.

show abstract

Section: Introductionmentioning

confidence: 99%

2.5- and 5-Gbps time-delay self-homodyne interference differential phase-shift keying optical receiver for space-to-ground communication link

et al. 2019

View full text Add to dashboard Cite

show abstract

“…FSMs have been widely used in many fields, such as imaging [2,3] and laser processing systems [4], free-space optical communications [5,6], and laser weaponry [7,8]. With a high bandwidth, FSMs are capable of fast response and good disturbance rejection [9].…”

Section: Introductionmentioning

confidence: 99%

Structural parameter design method for a fast-steering mirror based on a closed-loop bandwidth

2019

View full text Add to dashboard Cite

When a fast-steering mirror (FSM) system is designed, satisfying the performance requirements before fabrication and assembly is vital. This study proposes a structural parameter design approach for an FSM system based on the quantitative analysis of the required closedloop bandwidth. First, the open-loop transfer function of the FSM system is derived. In accordance with the transfer function, the notch filter and proportional-integral (PI) feedback controller are designed as a closed-loop controller. The gains of the PI controller are determined by maximizing the closed-loop bandwidth while ensuring the robustness of the system. Then, the two unknown variables of rotational radius and stiffness in the open-loop transfer function are optimized, considering the bandwidth as a constraint condition. Finally, the structural parameters of the stage are determined on the basis of the optimized results of rotational radius and stiffness. Simulations are conducted to verify the theoretical analysis. A prototype of the FSM system is fabricated, and corresponding experimental tests are conducted. Experimental results indicate that the bandwidth of the proposed FSM system is 117.6 Hz, which satisfies the minimum bandwidth requirement of 100 Hz.

show abstract

“…Liu et al . 12 experimentally studied the influence of the GF on FSOC performance, and the experimental results showed that a higher bandwidth is necessary to guarantee communication quality with increasing GF. Cao et al .…”

Section: Introductionmentioning

confidence: 99%

Performance analysis of an adaptive optics system for free-space optics communication through atmospheric turbulence

Wang

et al. 2018

Sci Rep

View full text Add to dashboard Cite

The performance of free-space optics communication (FSOC) is greatly degraded by atmospheric turbulence. Adaptive optics (AO) is an effective method for attenuating the influence. In this paper, the influence of the spatial and temporal characteristics of turbulence on the performance of AO in a FSOC system is investigated. Based on the Greenwood frequency (GF) and the ratio of receiver aperture diameter to atmospheric coherent length (D/r0), the relationship between FSOC performance (CE) and AO parameters (corrected Zernike modes number and bandwidth) is derived for the first time. Then, simulations and experiments are conducted to analyze the influence of AO parameters on FSOC performance under different GF and D/r0. The simulation and experimental results show that, for common turbulence conditions, the number of corrected Zernike modes can be fixed at 35 and the bandwidth of the AO system should be larger than the GF. Measurements of the bit error rate (BER) for moderate turbulence conditions (D/r0 = 10, fG = 60 Hz) show that when the bandwidth is two times that of GF, the average BER is decreased by two orders of magnitude compared with fG/f3dB = 1. These results and conclusions can provide important guidance in the design of an AO system for FSOC.

show abstract

Performance evaluation of coherent free space optical communications with a double-stage fast-steering-mirror adaptive optics system depending on the Greenwood frequency

Cited by 73 publications

References 17 publications

2.5- and 5-Gbps time-delay self-homodyne interference differential phase-shift keying optical receiver for space-to-ground communication link

2.5- and 5-Gbps time-delay self-homodyne interference differential phase-shift keying optical receiver for space-to-ground communication link

Structural parameter design method for a fast-steering mirror based on a closed-loop bandwidth

Performance analysis of an adaptive optics system for free-space optics communication through atmospheric turbulence

Contact Info

Product

Resources

About