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2.5- and 5-Gbps time-delay self-homodyne interference differential phase-shift keying optical receiver for space-to-ground communication link.
- Source :
- Optical Engineering; Jan2019, Vol. 58 Issue 1, p1-12, 12p
- Publication Year :
- 2019
-
Abstract
- 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. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 00913286
- Volume :
- 58
- Issue :
- 1
- Database :
- Complementary Index
- Journal :
- Optical Engineering
- Publication Type :
- Academic Journal
- Accession number :
- 137122215
- Full Text :
- https://doi.org/10.1117/1.OE.58.1.016114