Quantum satellite communication has the natural advantages of strong survival reliability and wide coverage, and is currently a research hotspot in the field of communication at home and abroad. The successful launch of the "Mozi" scientific experimental satellite has laid the foundation for the construction of the quantum space-earth integrated communication network. In order to further improve the communication performance of the quantum satellite-ground link, a tuning strategy based on quantum coupled associative feedback control (QCAFC) is proposed in this paper. QCAFC estimates the state information of atoms by measuring the photons leaked in the optical cavity, and adjusts the controller to change the spin state of the atoms in the optical cavity. The evolution of the system is studied, the influence of the QCAFC system on the performance parameters of the satellite-ground quantum communication is analyzed, and the simulation is verified. The simulation results show that in the amplitude damped channel, the QCAFC system can significantly improve the channel capacity and coherence. When transmitting in the plasma environment, when the particle radius is 5, when the transmission distance between the satellite and the earth increases from 50km to 200km, the bit error rate of the system without QCAFC is increased from 7.34×10-3 to 21.93×10-3, and the bit error rate of the system with QCAFC is increased from 4.81×10-3 to 14.72×10-3. Simulation results show that the use of QCAFC system has a significant improvement in the performance of quantum satellite communication.
Quantum satellite communication has the natural advantages of strong survival reliability and wide coverage, and is currently a research hotspot in the field of communication at home and abroad. The successful launch of the "Mozi" scientific experimental satellite has laid the foundation for the construction of the quantum space-earth integrated communication network. In order to further improve the communication performance of the quantum satellite-ground link, a tuning strategy based on quantum coupled associative feedback control (QCAFC) is proposed in this paper. QCAFC estimates the state information of atoms by measuring the photons leaked in the optical cavity, and adjusts the controller to change the spin state of the atoms in the optical cavity. The evolution of the system is studied, the influence of the QCAFC system on the performance parameters of the satellite-ground quantum communication is analyzed, and the simulation is verified. The simulation results show that in the amplitude damped channel, the QCAFC system can significantly improve the channel capacity and coherence. When transmitting in the plasma environment, when the particle radius is 5, when the transmission distance between the satellite and the earth increases from 50km to 200km, the bit error rate of the system without QCAFC is increased from 7.34×10-3 to 21.93×10-3, and the bit error rate of the system with QCAFC is increased from 4.81×10-3 to 14.72×10-3. Simulation results show that the use of QCAFC system has a significant improvement in the performance of quantum satellite communication.
Quantum satellite communication is a communication method with strong security and large coverage area, and it has become a hot research topic at home and abroad. The successful launch of the quantum satellite has laid an important foundation for future integrated quantum communication. When further studying the communication performance between quantum satellite-ground links, it is found that atmospheric particulate matter has a significant impact on quantum satellite communication performance. In this paper, by analyzing the extinction characteristics of atmospheric particles, a mathematical model of particle concentration, transmission distance and satellite-earth quantum energy is established, and the influence of atmospheric particles on communication parameters, bit error rate and entanglement degree is analyzed. The simulation results show that with the increase of particle concentration, the performance indicators of quantum satellite communication are affected to a certain extent. As the concentration of particulate matter in the atmosphere continues to decrease, the energy of the optical quantum signal continues to increase, and the quantum bit error rate increases with the increase in the concentration of atmospheric particulate matter and the transmission distance. The degree of quantum entanglement decreases with the increase of the particle size of atmospheric particles, and increases with the increase of visibility. The luminosity of light quantum will decrease with the increase of transmission height and the increase of surface particle concentration. By studying the optimization and adjustment strategy of quantum signal based on fidelity quantum relay satellite, simulation ensures the feasibility of this strategy. It is observed that the research in this paper can provide the necessary theoretical reference for the development of quantum space-ground integrated communication network.
In quantum satellite communication, when the optical quantum signal is transmitted between satellite and ground links, it will be affected by various natural environments.At the same time, haze has become one of the largest environmental problems in the world.Therefore, it is of great significance to study the communication performance of quantum satellites in haze atmosphere.In this paper, according to the scale distribution and vertical spatial concentration change of large aerosol haze particles, the extinction characteristic model of large aerosol haze particles and the attenuation model of atmospheric haze particle concentration and transmission height on quantum satellite ground link are established.Some important performance parameters in quantum satellite communication are analyzed for amplitude damping channel, depolarization channel and phase damping channel respectively, It includes the quantitative relationship between channel capacity, quantum fidelity, quantum bit error rate and entanglement and large aerosol haze particle concentration and transmission height.The simulation results show that with the increase of transmission distance and haze particle concentration, the channel capacity, quantum fidelity and entanglement of quantum satellite communication in different channels will decrease, and the bit error rate will increase.Therefore, the impact of large haze environment on quantum satellite communication should be fully considered in the actual process of quantum satellite communication, Adaptive adjustment of relevant parameters to ensure the normal operation of quantum satellite communication.
In order to study the communication performance and parameter analysis of the satellite-to-earth link of the quantum satellite under the condition of forming snowfall in the stratosphere, firstly, according to the distribution function and extinction characteristics of the concentric spherical ice water condensation nuclei in the stratosphere and the snowfall, according to the Mie theory, the system environment is obtained. The extinction efficiency factor establishes the relationship between the quantum signal transmission distance and link attenuation under different system environmental levels. Further studies have been done to establish the relationship between channel capacity, survival function, bit error rate, transmission distance, and system environment level under the condition of long-distance transmission of optical quantum signals at a moderate proportion of stratus cloud and snowfall. The simulation shows that as the transmission distance and environmental level increase, the link attenuation gradually increases, the channel capacity and survival function are greatly reduced, and the bit error rate increases. Therefore, when performing satellite-to-earth link communication, the relevant parameters of quantum communication should be adjusted adaptively to reduce the influence of snowfall caused by the formation of stratus clouds and improve the transmission performance of quantum communication.
In the atmospheric boundary layer far from the mainland, the complex climate environment, strong sea winds, and intermediate currents pose challenges to ocean satellite and starship communication. Especially in quantum communication, the interference of ionosphere, space plasma, and ice crystal particles can affect the stability and security of communication, which has become a research hotspot in the current field of starship communication. This article proposes an innovative method to optimize starship communication based on Quantum Entanglement Adaptive Control (QEAC). This article establishes the relationship between environmental factors and fidelity, bit error rate, and adaptive adjustment strategies. It compares the system performance parameters before and after the introduction of QEAC. This innovative method can improve the fidelity of quantum satellite communication systems under natural environmental interference through quantum entanglement adaptive control. Especially in the amplitude damping and depolarisation channels, the application of QEAC has significantly improved the stability of quantum starship communication. To verify the effectiveness of the proposed method, this paper conducted performance simulation experiments and achieved satisfactory results. Therefore, the optimization strategy based on quantum entanglement adaptive control proposed in this article is innovative and practical, providing a novel solution for solving the problems faced by ocean satellite communication. This study is of great significance for improving the stability and security of quantum starship communication under complex oceanic and meteorological conditions.
Quantum satellite communication is an essential part in building a global quantum communication network. In order to cope with the sudden interference brought by snowfall to the quantum satellite communication system, an adaptive adjustment strategy for quantum satellite communication performance based on the optimal average photon number is proposed based on the decoy state protocol and snowfall spectral distribution function for the depolarization channel characteristics. The relationship between snowfall intensity and communication elevation angle and the optimal average number of photons per pulse is established, and the bit error ratio(BER) and survival performance of the system before and after the adoption of this strategy is compared. The simulation results show that the BER of the system decreases from 0.07 and 0.085 to 0.046 and 0.064 for medium and heavy snowfall environments, respectively; if the minimum communication elevation angle is required to be 0.81, the survival capability of the system increases from 0.81 to 0.92 for heavy snowfall environment; if the channel survival capability is required to be 0.8, the minimum communication elevation angle of the satellite link can be adjusted from 26° to 18° for heavy snowfall environment. Therefore, the strategy proposed enables the system to cope with more intense snowfall, improves the transmission quality of small elevation angle communication, further reduces the BER of the quantum satellite communication system, and enhances the reliability of the system in the snowfall context.
To study the effect of PM2.5 on the communication performance of satellite-ground quantum links, firstly, the effect of PM2.5 particle concentration on channel parameters such as quantum communication link attenuation, channel fidelity, and channel utilization was analyzed, and parametric simulations were carried out based on the PM2.5 particle concentration spectral distribution function and Mie scattering theory to obtain its extinction efficiency factor. The simulation results show that the link attenuation factor increases from 0.221 to 5.085 when the PM2.5 particle concentration increases from 10 to 230 over a transmission distance of 14km. When the transmission distance is 10 km, and the particle concentration increases from 0 to 200, the channel fidelity decreases from 1 to 0.804. When the transmission distance is 5km, and the particle concentration increases from 30 to 200, the channel utilization decreases from 0.51 to 0.36. Therefore, the impact of PM2.5 on the performance of satellite-ground quantum link communication is more significant. According to the PM2.5 concentration, corresponding adjustment strategies can be adopted to improve the reliability of the transmission system and ensure the smooth implementation of quantum communication.