This paper first describes a binary Low-Density Parity-Check(LDPC)-coded Probabilistic Shaping(PS)scheme for Multiple-Input Multiple-Output(MIMO)systems based on Signal Space Diversity(SSD).Second,a Nonbinary(NB)LDPC-...This paper first describes a binary Low-Density Parity-Check(LDPC)-coded Probabilistic Shaping(PS)scheme for Multiple-Input Multiple-Output(MIMO)systems based on Signal Space Diversity(SSD).Second,a Nonbinary(NB)LDPC-coded PS scheme for MIMO systems based on SSD is proposed.The first scheme can be used to obtain a shaping gain,whereas the second can also realize a coding gain.The theoretical average mutual information of the optimized rotated quadrature amplitude modulation constellations is analyzed and the simulated error per-formance with 22 and 44 MIMO schemes is investigated.The theoretical average mutual information analysis and simulation results show that the proposed NB LDPC-coded PS scheme for MIMO systems based on SSD is reliable and robust,and is therefore suitable for future wireless communication systems.展开更多
In this Letter, we provide a novel maximum a posteriori probability detection-based decision-directed carrier phase estimation(MAP-DDCPE) algorithm. The introduced probability-aware maximum a posteriori probability(MA...In this Letter, we provide a novel maximum a posteriori probability detection-based decision-directed carrier phase estimation(MAP-DDCPE) algorithm. The introduced probability-aware maximum a posteriori probability(MAP) detection avoids the decision errors brought by an ununiform probability distribution, which enhances the phase-tracking ability for the probabilistic shaping(PS) signals. With the proposed MAP-DDCPE, we experimentally demonstrate the 96-channel transmission that delivers 40-GBaud polarization division multiplexing(PDM) PS-64-ary quadrature amplitude modulation(64QAM) signals over the 2-km nested anti-resonant nodeless fiber(NANF). We believe the PS-assisted broadband NANF transmission enabled by the MAP-DDCPE is a promising solution for large-capacity optical communication.展开更多
In this paper,a carrier-less amplitude and phase modulation passive optical network(CAP-PON)scheme is proposed based on dynamic probabilistic shaping(DPS)and Rubik’s cube encryption in optical access networks.The key...In this paper,a carrier-less amplitude and phase modulation passive optical network(CAP-PON)scheme is proposed based on dynamic probabilistic shaping(DPS)and Rubik’s cube encryption in optical access networks.The key is generated from a novel five-dimensional entangled chaos model for dynamic probabilistic shaping and Rubik’s cube encryption.To verify the performance of the encryption scheme,an experimental demonstration of 70 Gb/s(7×10 Gb/s)encrypted DPS-3D-CAP signal transmission over 2 km weakly coupled 7-core fiber is performed.The key space of the new five-dimensional entangled chaos model reaches 10173,and the interference level reaches 100%.Experimental results show that the receiver sensitivity increases by 1.47 dB compared to the conventional uniform 3D-CAP due to the introduction of dynamic probabilistic shaping.展开更多
To increase the spectral efficiency of the underwater acoustic(UWA)communication system,the high order quadrature amplitude modulations(QAM)are deployed.Recently,the prob-abilistic constellation shaping(PCS)has been a...To increase the spectral efficiency of the underwater acoustic(UWA)communication system,the high order quadrature amplitude modulations(QAM)are deployed.Recently,the prob-abilistic constellation shaping(PCS)has been a novel technology to improve the spectral efficiency.The PCS with high-order QAM is introduced into the UWA communication system.A turbo equal-ization scheme with PCS was proposed to cancel the severe inter-symbol interference(ISI).The non-zero a priori information is available for the equalizer and decoder before turbo iteration.A pri-ori hard decision approach is proposed to improve the detection performance and the equalizer con-vergence speed.At the initial turbo iteration,the relation between the a priori information and the probability of the amplitude of 16QAM symbols in one dimension is given.The simulation results verified the efficiency of the proposed method,and compared to the uniform distribution(UD),the PCS-16QAM had a significant improvement of the bit error rate(BER)performance with PCS-ad-aptive turbo equalization(PCS-ATEQ).The UWA communication experiments further verified the performance superiority of the proposed method.展开更多
We successfully demonstrate 32-Gbaud Probabilistically Shaped 4096-ary Quadrature Amplitude Modulation(PS-4096QAM)TeraHertz(THz)signal wired transmission at 325 GHz over the 1-m Hollow-Core Fiber(HCF)in a photon-assis...We successfully demonstrate 32-Gbaud Probabilistically Shaped 4096-ary Quadrature Amplitude Modulation(PS-4096QAM)TeraHertz(THz)signal wired transmission at 325 GHz over the 1-m Hollow-Core Fiber(HCF)in a photon-assisted THz-wave communication system.By employing advanced Digital Signal Processing(DSP)and the PS technique,the 352-Gbit/s line rate(288-Gbit/s net rate)delivery with a net Spectral Efficiency(SE)of 9 bit/s/Hz is realized in the experiment,satisfying the 0.86-Normalized Generalized Mutual Information(NGMI)Low-Density Parity-Check(LDPC)threshold.展开更多
We demonstrated a fiber-terahertz(THz)-fiber communication system at the D-band based on full photonic conversions,exploiting a modified unitraveling-carrier photodiode(MUTC-PD)module to achieve optical-to-THz convers...We demonstrated a fiber-terahertz(THz)-fiber communication system at the D-band based on full photonic conversions,exploiting a modified unitraveling-carrier photodiode(MUTC-PD)module to achieve optical-to-THz conversion at the transmitter end and an ultrabroadband packaged thin-film lithium niobate Mach-Zehnder modulator(MZM)to convert the THz signal to the optical signal at the receiver end.This system successfully realized the transmission of 33-Gbaud 16-quadrature amplitude modulation(QAM)and 31-Gbaud probabilistic shaping-64-QAM signals through 10-km standard singlemode fiber(SSMF),0.6-m wireless distance,and the subsequent 5-km SSMF,achieving net data rates of 116.03 and123.72 Gbps,respectively.展开更多
Probabilistically shaped(PS) pulse amplitude modulation(PAM) is a promising technique for intra-data-center networks due to its superior performance, for which a low-complexity and cost-effective distributed matching ...Probabilistically shaped(PS) pulse amplitude modulation(PAM) is a promising technique for intra-data-center networks due to its superior performance, for which a low-complexity and cost-effective distributed matching method is critical. In this work, we propose an energy-level-assigned method to yield PS-PAM-4 signals with various bit rates based on variable probabilistic distributions. We experimentally demonstrate the proposed method in a 25 Gbaud PS-PAM-4 transmission over a bandwidth of approximately 10 GHz. Compared to a uniform PAM-4 system, the proposed multi-distributed PS-PAM-4 system approaches the hard decision threshold at a wide range of received optical power for different applications.展开更多
Probabilistically shaped(PS)high-order quadrature amplitude modulation(QAM)signals are attractive to coherent optical communication due to increased spectral efficiency.However,standard digital signal processing algor...Probabilistically shaped(PS)high-order quadrature amplitude modulation(QAM)signals are attractive to coherent optical communication due to increased spectral efficiency.However,standard digital signal processing algorithms are not optimal to demodulate PS high-order QAM signals.Therefore,a compromise equalization is indispensable to compensate the residual distortion.Meanwhile,the performance of conventional blind equalization highly depends on the accurate amplitude radius and distribution of the signals.The PS high-order QAM signals make the issue worsen because of indistinct amplitude distributions.In this work,we proposed an optimized blind equalization by utilizing a peak-density K-means clustering algorithm to accurately track the amplitude radius and distribution.We experimentally demonstrated the proposed method in a PS 256-QAM coherent optical transmission system and achieved approximately 1 dB optical signal-to-noise ratio improvement at the bit error rate of 1×10^(−3).展开更多
In this work,we proposed and experimentally demonstrated a novel probabilistic shaping(PS)64-ary quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)with low-density parity-check(LDPC)-...In this work,we proposed and experimentally demonstrated a novel probabilistic shaping(PS)64-ary quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)with low-density parity-check(LDPC)-coded modulation in a W-band radio-over-fiber(RoF)system using envelope detection.The proposed PS scheme has the advantages of no complex multiplication and division operations and low hardware implementation complexity.In our experiments,the two-stage bit weight distribution matching-based PS-64QAM OFDM signals with a rate of 28.13 Gb/s transmission over 4 m wireless+45-km standard single-mode fiber transmission can be achieved.The system performance is investigated under one LDPC code rate(3/4)and two PS parameter values(k=3 and 9).The experimental results show that the receiver power sensitivity and the system fiber nonlinear effect tolerance can be significantly improved compared with uniformly distributed OFDM signals.展开更多
基金supported by Fundamental Research Program of Shanxi Province(202203021212159).
文摘This paper first describes a binary Low-Density Parity-Check(LDPC)-coded Probabilistic Shaping(PS)scheme for Multiple-Input Multiple-Output(MIMO)systems based on Signal Space Diversity(SSD).Second,a Nonbinary(NB)LDPC-coded PS scheme for MIMO systems based on SSD is proposed.The first scheme can be used to obtain a shaping gain,whereas the second can also realize a coding gain.The theoretical average mutual information of the optimized rotated quadrature amplitude modulation constellations is analyzed and the simulated error per-formance with 22 and 44 MIMO schemes is investigated.The theoretical average mutual information analysis and simulation results show that the proposed NB LDPC-coded PS scheme for MIMO systems based on SSD is reliable and robust,and is therefore suitable for future wireless communication systems.
基金supported by the National Key R&D Program of China (No. 2018YFB1800905)the National Natural Science Foundation of China (Nos. 61935005, 61720106015, 61835002, and 62127802)。
文摘In this Letter, we provide a novel maximum a posteriori probability detection-based decision-directed carrier phase estimation(MAP-DDCPE) algorithm. The introduced probability-aware maximum a posteriori probability(MAP) detection avoids the decision errors brought by an ununiform probability distribution, which enhances the phase-tracking ability for the probabilistic shaping(PS) signals. With the proposed MAP-DDCPE, we experimentally demonstrate the 96-channel transmission that delivers 40-GBaud polarization division multiplexing(PDM) PS-64-ary quadrature amplitude modulation(64QAM) signals over the 2-km nested anti-resonant nodeless fiber(NANF). We believe the PS-assisted broadband NANF transmission enabled by the MAP-DDCPE is a promising solution for large-capacity optical communication.
基金supported by the National Key Research and Development Program of China(No.2023YFB2804901)the National Natural Science Foundation of China(Nos.U2001601,62225503,and 62205151)the Jiangsu Provincial Key Research and Development Program(Nos.BE2022079 and BE2022055-2).
文摘In this paper,a carrier-less amplitude and phase modulation passive optical network(CAP-PON)scheme is proposed based on dynamic probabilistic shaping(DPS)and Rubik’s cube encryption in optical access networks.The key is generated from a novel five-dimensional entangled chaos model for dynamic probabilistic shaping and Rubik’s cube encryption.To verify the performance of the encryption scheme,an experimental demonstration of 70 Gb/s(7×10 Gb/s)encrypted DPS-3D-CAP signal transmission over 2 km weakly coupled 7-core fiber is performed.The key space of the new five-dimensional entangled chaos model reaches 10173,and the interference level reaches 100%.Experimental results show that the receiver sensitivity increases by 1.47 dB compared to the conventional uniform 3D-CAP due to the introduction of dynamic probabilistic shaping.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA22030101)the National Natural Science Foundation of China(No.61971472)the Institute of Acoustics,Chinese Academy of Sciences Free Exploration Project(No.ZYTS202003).
文摘To increase the spectral efficiency of the underwater acoustic(UWA)communication system,the high order quadrature amplitude modulations(QAM)are deployed.Recently,the prob-abilistic constellation shaping(PCS)has been a novel technology to improve the spectral efficiency.The PCS with high-order QAM is introduced into the UWA communication system.A turbo equal-ization scheme with PCS was proposed to cancel the severe inter-symbol interference(ISI).The non-zero a priori information is available for the equalizer and decoder before turbo iteration.A pri-ori hard decision approach is proposed to improve the detection performance and the equalizer con-vergence speed.At the initial turbo iteration,the relation between the a priori information and the probability of the amplitude of 16QAM symbols in one dimension is given.The simulation results verified the efficiency of the proposed method,and compared to the uniform distribution(UD),the PCS-16QAM had a significant improvement of the bit error rate(BER)performance with PCS-ad-aptive turbo equalization(PCS-ATEQ).The UWA communication experiments further verified the performance superiority of the proposed method.
基金supported by National Key R&D Program of China(2018YFB1800900)National Natural Science Foundation of China(61935005,91938202,61720106015,61835002,61805043,62127802).
文摘We successfully demonstrate 32-Gbaud Probabilistically Shaped 4096-ary Quadrature Amplitude Modulation(PS-4096QAM)TeraHertz(THz)signal wired transmission at 325 GHz over the 1-m Hollow-Core Fiber(HCF)in a photon-assisted THz-wave communication system.By employing advanced Digital Signal Processing(DSP)and the PS technique,the 352-Gbit/s line rate(288-Gbit/s net rate)delivery with a net Spectral Efficiency(SE)of 9 bit/s/Hz is realized in the experiment,satisfying the 0.86-Normalized Generalized Mutual Information(NGMI)Low-Density Parity-Check(LDPC)threshold.
基金supported by the National Key Research and Development Program of China(No.2022YFB2903600)the National Natural Science Foundation of China(Nos.62235005,62171137,and 61925104)。
文摘We demonstrated a fiber-terahertz(THz)-fiber communication system at the D-band based on full photonic conversions,exploiting a modified unitraveling-carrier photodiode(MUTC-PD)module to achieve optical-to-THz conversion at the transmitter end and an ultrabroadband packaged thin-film lithium niobate Mach-Zehnder modulator(MZM)to convert the THz signal to the optical signal at the receiver end.This system successfully realized the transmission of 33-Gbaud 16-quadrature amplitude modulation(QAM)and 31-Gbaud probabilistic shaping-64-QAM signals through 10-km standard singlemode fiber(SSMF),0.6-m wireless distance,and the subsequent 5-km SSMF,achieving net data rates of 116.03 and123.72 Gbps,respectively.
基金This work was supported by the National Natural Science Foundation of China(No.62075147).
文摘Probabilistically shaped(PS) pulse amplitude modulation(PAM) is a promising technique for intra-data-center networks due to its superior performance, for which a low-complexity and cost-effective distributed matching method is critical. In this work, we propose an energy-level-assigned method to yield PS-PAM-4 signals with various bit rates based on variable probabilistic distributions. We experimentally demonstrate the proposed method in a 25 Gbaud PS-PAM-4 transmission over a bandwidth of approximately 10 GHz. Compared to a uniform PAM-4 system, the proposed multi-distributed PS-PAM-4 system approaches the hard decision threshold at a wide range of received optical power for different applications.
基金This work was supported in part by the National Key R&D Program of China(No.2020YFB1805805)the National Natural Science Foundation of China(No.62075147).
文摘Probabilistically shaped(PS)high-order quadrature amplitude modulation(QAM)signals are attractive to coherent optical communication due to increased spectral efficiency.However,standard digital signal processing algorithms are not optimal to demodulate PS high-order QAM signals.Therefore,a compromise equalization is indispensable to compensate the residual distortion.Meanwhile,the performance of conventional blind equalization highly depends on the accurate amplitude radius and distribution of the signals.The PS high-order QAM signals make the issue worsen because of indistinct amplitude distributions.In this work,we proposed an optimized blind equalization by utilizing a peak-density K-means clustering algorithm to accurately track the amplitude radius and distribution.We experimentally demonstrated the proposed method in a PS 256-QAM coherent optical transmission system and achieved approximately 1 dB optical signal-to-noise ratio improvement at the bit error rate of 1×10^(−3).
基金supported by the Natural Science Research Startup Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(No.NY223144)。
文摘In this work,we proposed and experimentally demonstrated a novel probabilistic shaping(PS)64-ary quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)with low-density parity-check(LDPC)-coded modulation in a W-band radio-over-fiber(RoF)system using envelope detection.The proposed PS scheme has the advantages of no complex multiplication and division operations and low hardware implementation complexity.In our experiments,the two-stage bit weight distribution matching-based PS-64QAM OFDM signals with a rate of 28.13 Gb/s transmission over 4 m wireless+45-km standard single-mode fiber transmission can be achieved.The system performance is investigated under one LDPC code rate(3/4)and two PS parameter values(k=3 and 9).The experimental results show that the receiver power sensitivity and the system fiber nonlinear effect tolerance can be significantly improved compared with uniformly distributed OFDM signals.
