The influence of the nonlinear propagation effect on three 400 Gb/s/ch (400G) optical fiber communication systems with typical modulation formats, dual-carrier 16-quadrature amplitude modulation (16QAM), single-ca...The influence of the nonlinear propagation effect on three 400 Gb/s/ch (400G) optical fiber communication systems with typical modulation formats, dual-carrier 16-quadrature amplitude modulation (16QAM), single-carrier 16QAM (single-16QAM), and four-carrier quadrature phase-shift keying, are investigated. The received optical signal-to-noise ratio (OSNR), affected by the nonlinear interference noise together with the amplified spontaneous emission noise, are compared with three 400G systems and a standard 100 Gb/s/ch system by numerical simulations. Both single channel and multichannel cases are considered. Single-16QAM is found to have the best OSNR among those modulation formats.展开更多
We experimentally investigate multigranularity optical subband switching functionality between two superchannels with slight error vector magnitude penalty. One is 4×39 Gb/s polarization-division-multiplexed(PDM...We experimentally investigate multigranularity optical subband switching functionality between two superchannels with slight error vector magnitude penalty. One is 4×39 Gb/s polarization-division-multiplexed(PDM) quadrature phase shift keying discrete Fourier transform spread orthogonal frequency division multiplexing(DFT-spread-OFDM) superchannel with 12.5 GHz band spacing. The other is 8×29 Gb/s PDM-16-quadrature amplitude modulation Nyquist pulse shaping superchannel with 6.25 GHz band spacing. To the best of our knowledge, this is the first time that optical switching functionality for individual band between different superchannels with multigranularity is realized.展开更多
A data-aided method of joint frequency offset and chromatic dispersion estimation based on the Chu training sequences is shown in 112 Gb/s polarization-multiplexed (PM) quadrature phase-shift keying and 224 Gb/s PM-...A data-aided method of joint frequency offset and chromatic dispersion estimation based on the Chu training sequences is shown in 112 Gb/s polarization-multiplexed (PM) quadrature phase-shift keying and 224 Gb/s PM-16-quadrature amplitude modulation with different pulse-shaping filters, respectively. The proposed method achieves a good accuracy and is verified to be robust to polarization mode dispersion.展开更多
Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has bee...Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has been made to ascertain which modulation technique proves better for communication. This paper investigates the performance of ASK and PSK modulation based FSO system by varying different FSO parameters under several conditions including haze, rain, mist and fog. Finally, simulation results are analysed and discussed.展开更多
The history of the development of Chinese telemetry is introduced in the paper. The new telemetry ground station and the new onboard space telemetry system, with the idea of systematic design and the specification, ar...The history of the development of Chinese telemetry is introduced in the paper. The new telemetry ground station and the new onboard space telemetry system, with the idea of systematic design and the specification, are described.展开更多
幅度与相位联合调制(Amplitude and Phase Shift Keying,APSK)对于映射到星座图上同一个符号点的不同比特具有不均等的差错保护,其中受保护程度较低的比特限制了编码调制系统的整体误码性能。为消除这一限制,提出了一种非均衡编码方案,...幅度与相位联合调制(Amplitude and Phase Shift Keying,APSK)对于映射到星座图上同一个符号点的不同比特具有不均等的差错保护,其中受保护程度较低的比特限制了编码调制系统的整体误码性能。为消除这一限制,提出了一种非均衡编码方案,即对不同保护程度的数据进行分组,通过比特交织的方式匹配不同纠错能力的低密度奇偶校验码(Low Density Parity Check Code,LDPC)进行编码。在64-APSK调制方式下进行计算机仿真,仿真结果表明:均衡编码方案相比传统编码调制方案具有0.3 dB以上的性能增益。展开更多
基金supported by the National Key Scientific Instrument and Equipment Development Project of China under Grant No.2014YQ510403
文摘The influence of the nonlinear propagation effect on three 400 Gb/s/ch (400G) optical fiber communication systems with typical modulation formats, dual-carrier 16-quadrature amplitude modulation (16QAM), single-carrier 16QAM (single-16QAM), and four-carrier quadrature phase-shift keying, are investigated. The received optical signal-to-noise ratio (OSNR), affected by the nonlinear interference noise together with the amplified spontaneous emission noise, are compared with three 400G systems and a standard 100 Gb/s/ch system by numerical simulations. Both single channel and multichannel cases are considered. Single-16QAM is found to have the best OSNR among those modulation formats.
基金supported by the National 973 Program of China(No.2010CB328201)the National 863 Program of China(No.2012AA011302)the National Natural Science Foundation of China(No.61077053)
文摘We experimentally investigate multigranularity optical subband switching functionality between two superchannels with slight error vector magnitude penalty. One is 4×39 Gb/s polarization-division-multiplexed(PDM) quadrature phase shift keying discrete Fourier transform spread orthogonal frequency division multiplexing(DFT-spread-OFDM) superchannel with 12.5 GHz band spacing. The other is 8×29 Gb/s PDM-16-quadrature amplitude modulation Nyquist pulse shaping superchannel with 6.25 GHz band spacing. To the best of our knowledge, this is the first time that optical switching functionality for individual band between different superchannels with multigranularity is realized.
基金supported by the National Natural Science Foundation of China(No.61205065)the National "863" Project of China(No.2013AA013401)the Open Fund of State Key Laboratory of optical fiber communication network with the new type of optical communication system(Shanghai Jiao Tong University)(No.2013GZKF031310)
文摘A data-aided method of joint frequency offset and chromatic dispersion estimation based on the Chu training sequences is shown in 112 Gb/s polarization-multiplexed (PM) quadrature phase-shift keying and 224 Gb/s PM-16-quadrature amplitude modulation with different pulse-shaping filters, respectively. The proposed method achieves a good accuracy and is verified to be robust to polarization mode dispersion.
文摘Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has been made to ascertain which modulation technique proves better for communication. This paper investigates the performance of ASK and PSK modulation based FSO system by varying different FSO parameters under several conditions including haze, rain, mist and fog. Finally, simulation results are analysed and discussed.
文摘The history of the development of Chinese telemetry is introduced in the paper. The new telemetry ground station and the new onboard space telemetry system, with the idea of systematic design and the specification, are described.
文摘幅度与相位联合调制(Amplitude and Phase Shift Keying,APSK)对于映射到星座图上同一个符号点的不同比特具有不均等的差错保护,其中受保护程度较低的比特限制了编码调制系统的整体误码性能。为消除这一限制,提出了一种非均衡编码方案,即对不同保护程度的数据进行分组,通过比特交织的方式匹配不同纠错能力的低密度奇偶校验码(Low Density Parity Check Code,LDPC)进行编码。在64-APSK调制方式下进行计算机仿真,仿真结果表明:均衡编码方案相比传统编码调制方案具有0.3 dB以上的性能增益。