The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean...The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12 and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be extended to domestic and international use. This system played a very important role in the 14th Chinese Antarctic Exploration Navigation, and was introduced a broad attention paid by Chinese newspapers and TV Stations.展开更多
Space–time metasurfaces are promising candidates for breaking Lorentz reciprocity,which constrains light propagation in numerous practical applications.There is a substantial difference between carrier and modulation...Space–time metasurfaces are promising candidates for breaking Lorentz reciprocity,which constrains light propagation in numerous practical applications.There is a substantial difference between carrier and modulation frequencies in space–time photonic metasurfaces that leads to negligible spatial pathway variation of light and weak nonreciprocal response.To surmount this obstacle,herein,the design principle of a high-quality-factor space–time gradient metasurface is demonstrated at the near-infrared regime that increases the lifetime of photons and allows for strong power isolation by lifting the adiabaticity of modulation.The all-dielectric metasurface consists of an array of silicon subwavelength gratings(SWGs)that are separated from distributed Bragg reflectors by a silica buffer.The resonant mode with ultrahigh quality-factor exceeding 10^(4)is excited within the SWG,which is characterized as magnetic octupole and features strong field localization.The SWGs are configured as multijunction p–n layers,whose multigate biasing with time-varying waveforms enables modulation of carriers in space and time.The proposed nonreciprocal metasurface is exploited for free-space optical power isolation by virtue of modulationinduced phase shift.It is shown that under time reversal and by interchanging the directions of incident and observation ports,power isolation of≈35 dB can be maintained between the two ports in free space.展开更多
基金the State Oceanic Administration "95" Principal Project "9501" National Antarctic"95" Principal
文摘The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12 and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be extended to domestic and international use. This system played a very important role in the 14th Chinese Antarctic Exploration Navigation, and was introduced a broad attention paid by Chinese newspapers and TV Stations.
基金supported in part by Air Force Office of Scientific Research(Grant No.FA9550-18-1-0354).
文摘Space–time metasurfaces are promising candidates for breaking Lorentz reciprocity,which constrains light propagation in numerous practical applications.There is a substantial difference between carrier and modulation frequencies in space–time photonic metasurfaces that leads to negligible spatial pathway variation of light and weak nonreciprocal response.To surmount this obstacle,herein,the design principle of a high-quality-factor space–time gradient metasurface is demonstrated at the near-infrared regime that increases the lifetime of photons and allows for strong power isolation by lifting the adiabaticity of modulation.The all-dielectric metasurface consists of an array of silicon subwavelength gratings(SWGs)that are separated from distributed Bragg reflectors by a silica buffer.The resonant mode with ultrahigh quality-factor exceeding 10^(4)is excited within the SWG,which is characterized as magnetic octupole and features strong field localization.The SWGs are configured as multijunction p–n layers,whose multigate biasing with time-varying waveforms enables modulation of carriers in space and time.The proposed nonreciprocal metasurface is exploited for free-space optical power isolation by virtue of modulationinduced phase shift.It is shown that under time reversal and by interchanging the directions of incident and observation ports,power isolation of≈35 dB can be maintained between the two ports in free space.
