Abstract: This application provides a communication method and apparatus applying a Huygens equivalent surface, to increase energy of a wanted signal and a degree of freedom of a spatial channel, and improve communication performance. The method includes: A receive end receives a first receiving signal based on a first Huygens equivalent surface. The receive end may further send first indication information. The first indication information includes indication information of at least one Huygens equivalent surface, the indication information of the at least one Huygens equivalent surface is determined based on a second Huygens equivalent surface, and the second Huygens equivalent surface corresponds to the first receiving signal.

Abstract: A first device receives a first signal sent by a second device, receives a second signal sent by a third device, and determines a first length based on first time, second time, and delay duration. The first time is time at which the first device receives the first signal. The second time is time at which the first device receives the second signal. The first length is a distance from an intersection point of a first straight line on which a terminal device is located and a first transmission line between a first network device and a second network device to the second network device, and the first straight line is perpendicular to the first transmission line.

Abstract: A Cassegrain or quasi-Cassegrain structure objective lens is used in a polar MOKE metrology system. The quasi-Cassegrain reflective objective lens includes a primary concave mirror and a secondary mirror. The primary concave mirror has a wider diameter than the secondary mirror and defines an aperture through which the laser beam is configured to be transmitted toward the secondary mirror. The secondary mirror can be convex, concave, or have a flat surface.

Abstract: The present invention provides synthetic nucleic acid sequences comprising 10-30 nucleotides of the J2L and B6R gene regions and/or the 3? non-coding region of the Monkeypox virus genome, and a synthetic nucleic acid sequence comprising 10-30 nucleotides of a nucleic acid sequence that is complementary to at least one of those regions. Also provided are compositions comprising the sequences, and uses of the sequences in diagnostic kits. The present invention further provides a primer and probe set for determining the presence or absence of Monkeypox virus in a biological sample, wherein the primer set comprises at least one of the synthetic nucleic acid sequences. Also provided are a composition comprising the primer and probe set, and use of the primer and probe set in a diagnostic kit. Finally, the present invention provides kits and methods for determining the presence or absence of Monkeypox virus in a biological sample.

Abstract: A Flettner rotor that employs localized suction over its surface improves performance and fuel efficiency. Simulations and analysis show that such a method can significantly improve the performance of the Flettner rotor. Improvements in rotor performance enable reduction in fuel costs and greenhouse gas emission by ships or other modes of transport. Improvements in rotor performance can also reduce noise for applications such as drones or other devices having rotors.

Abstract: Embodiments of this application provide a leaky coaxial cable and a communication system. The leaky cable includes: an inner conductor, an insulation layer, and an outer conductor, where the insulation layer is configured to separate the inner conductor from the outer conductor; and the outer conductor includes M perforated segments and N non-perforated segments, the M perforated segments and the N non-perforated segments are alternately arranged, at least one of the M perforated segments includes at least three leak holes, spacings between leak holes in each of the at least one perforated segment are the same, and M and N are positive integers greater than or equal to 1.

Abstract: Embodiments of the present invention disclose a communication method and apparatus, and a computer-readable storage medium. The method includes: An environment controller sends location information and a state pattern to a control board via an access network device. The control board adjusts a location and a state of the control board based on the location information and the state pattern. In embodiments of the present invention, a propagation environment of surrounding space may be optimized by adjusting the location and the state of the control board, to improve a throughput of a communication system.

Abstract: This application discloses a time reversal-based communication method and apparatus. The method includes: A first device receives first time reversal detection signals from a second device in M spatial channels from a first direction, a second direction, and a third direction, where M is a quantity of spatial channels on which the first device is capable of working, and the first direction, the second direction, and the third direction are perpendicular to each other. The first device determines N1 spatial channels in the M spatial channels based on the first time reversal detection signals. The first device communicates with the second device based on N1 first time reversal vector sequences through the N1 spatial channels, where the N1 first time reversal vector sequences are determined by the first device based on the first time reversal detection signals received in the N1 spatial channels from the three directions.

Abstract: A method for extracting water includes introducing a first gas into a lower inner volume section of a vessel via a first jet. The first gas stirs regolith in the lower inner volume section and at least partially separates a first portion of the regolith from a second portion of the regolith in the lower inner volume section. The first portion floats up through the lower inner volume section and into an upper inner volume section of the vessel. The method also includes introducing a second gas into the upper inner volume section via a second jet. The second gas causes particles of the first portion of the regolith to collide with one another, which exposes ice in the first portion of the regolith. The first portion of the regolith is heated in the upper inner volume section, which causes the ice to sublimate into water vapor.

Abstract: The present disclosure relates to precoding matrix determining methods, devices, and systems. In one example method, a receive end device obtains channel state information (CSI) of a first channel and information about P antenna port groups of a transmit end device. The receive end device determines V orbital angular momentum (OAM) mode groups based on the CSI of the first channel and first OAM modes, determines a first precoding matrix based on the P antenna port groups of the transmit end device and the V OAM mode groups, and sends, to the transmit end device, first indication information indicating the first precoding matrix. The transmit end device receives the first indication information, and determines the first precoding matrix based on the first indication information.

Abstract: This application relates to communication methods and apparatuses. In an example method, a first communication apparatus generates first indication information, and sends the first indication information to a second communication apparatus. The first indication information indicates M orbital angular momentum (OAM) modes jointly supported by the first communication apparatus and the second communication apparatus, where there is a correspondence between N OAM modes in the M OAM modes and a demodulation reference signal (DMRS) port.

Abstract: An antenna includes: a dielectric plate provided with a first surface and a second surface; a ground plane located on the first surface; and an antenna unit. A size of the antenna unit is a preset length, the antenna unit includes at least three antenna elements in a ring arrangement, and each antenna element includes a first patch, a second patch, and a third patch that are located on the second surface, and three conductive portions that penetrate through the first surface and the second surface.

Abstract: A Flettner rotor that employs localized suction over its surface improves performance and fuel efficiency. Simulations and analysis show that such a method can significantly improve the performance of the Flettner rotor. Improvements in rotor performance enable reduction in fuel costs and greenhouse gas emission by ships or other modes of transport. Improvements in rotor performance can also reduce noise for applications such as drones or other devices having rotors.

Abstract: A method includes sending a first orbital angular momentum (OAM) reference signal in a first beam direction. The first OAM reference signal is used to determine a second beam direction from the first beam direction. The method also includes receiving first indication information. The first indication information includes information about the second beam direction. The method also includes sending a second OAM reference signal in the second beam direction. The second OAM reference signal is used to determine antenna information and a second channel response of the second OAM reference signal. The method also includes receiving second indication information. The second indication information is determined based on the second channel response and the antenna information. The second indication information is used to determine a transmission manner. The transmission manner includes OAM wave transmission, plane wave transmission, or joint transmission of OAM and a plane wave.

Abstract: A radio resource identification method and an apparatus. The method includes: obtaining OAM mode domain information, where the OAM mode domain information includes a first OAM mode domain identifier, the first OAM mode domain identifier corresponds to a first transmission parameter of a vortex electromagnetic wave in a first OAM physical mode, or the first OAM mode domain identifier corresponds to a first ratio between the first transmission parameter and a reference value, and the reference value includes a transmission parameter of a plane electromagnetic wave or a transmission parameter of a vortex electromagnetic wave in a specified OAM physical mode in a plurality of OAM physical modes; and any plurality of waveform symbols pass through a same vortex electromagnetic wave channel; and determining a radio resource used for uplink transmission or downlink transmission.

Abstract: A quantum communication method, an apparatus, and a system are provided. The method includes: modulating a first symbol to an ith direction vector of a first electric wave based on a preset mapping relationship, to obtain a second electric wave; and transmitting the second electric wave, where the first electric wave supports M direction vectors, the ith direction vector of the first electric wave is one of the M direction vectors of the first electric wave, the first symbol is a symbol corresponding to first data, the ith direction vector of the first electric wave corresponds to an ith distribution result, the ith distribution result is obtained by converting the second electric wave into an energy quantum. The first symbol may be modulated to a direction vector of the first electric wave, and this application is compatible with the conventional technology.

Abstract: The present disclosure relates to precoding matrix determining methods, devices, and systems. In one example method, a receive end device obtains channel state information (CSI) of a first channel and information about P antenna port groups of a transmit end device. The receive end device determines V orbital angular momentum (OAM) mode groups based on the CSI of the first channel and first OAM modes, determines a first precoding matrix based on the P antenna port groups of the transmit end device and the V OAM mode groups, and sends, to the transmit end device, first indication information indicating the first precoding matrix. The transmit end device receives the first indication information, and determines the first precoding matrix based on the first indication information.

Abstract: A Cassegrain or quasi-Cassegrain structure objective lens is used in a polar MOKE metrology system. The quasi-Cassegrain reflective objective lens includes a primary concave mirror and a secondary mirror. The primary concave mirror has a wider diameter than the secondary mirror and defines an aperture through which the laser beam is configured to be transmitted toward the secondary mirror. The secondary mirror can be convex, concave, or have a flat surface.

Abstract: This application provides a quantum communication method, an apparatus, and a system. The method includes: modulating a first symbol to an ith direction vector of a first electric wave based on a preset mapping relationship, to obtain a second electric wave; and transmitting the second electric wave, where the first electric wave supports M direction vectors, the ith direction vector of the first electric wave is one of the M direction vectors of the first electric wave, the first symbol is a symbol corresponding to first data, the ith direction vector of the first electric wave corresponds to an ith distribution result, the ith distribution result is obtained by converting the second electric wave into an energy quantum. In this application, the first symbol may be modulated to a direction vector of the first electric wave, and this application is compatible with the conventional technology.

Abstract: A laser beam is directed through a transmissive axicon telescope or a reflective axicon telescope such as in a magneto-optic Kerr effect metrology system. With the transmissive axicon telescope, a Gaussian beam profile is directed through a first axicon lens and a second axicon lens. The first axicon lens and second axicon lens transfer the Gaussian beam profile of the laser beam to a hollowed laser ring. The laser beam with a hollowed laser ring can be directed through a Schwarzschild reflective objective. With the reflective axicon telescope, the laser beam is directed through two conical mirrors that are fully reflective. One of the conical mirrors defines a central hole that the laser beam passes through.