optical satellite communication

Satellite communication terminal equipment is a device in the user segment of the mobile satellite communication system, including Mobile device and hand-held terminal. In terms of types, there were many satellite communication terminal devices in different application scenarios. For example, in the Aerospace Mobile Satellite System (AMSS), the receiving and transmitting equipment on the aircraft belonged to the aerospace mobile satellite communication terminal. It was composed of a satellite data unit (SDIU), a radio frequency unit (RFO), a high power amplifier (HPA), and an antenna. It was used to provide voice and data communication between the aircraft and the ground for the crew and passengers. It was required for functions such as cockpit voice, data, automatic position and status reports, and passenger direct dial phones. The satellite communication terminal of Tongyu Communication (002792.SY) was mainly a mobile communication antenna, such as a ship-borne satellite antenna, a car-mounted satellite antenna, etc. There were also popular smart phones such as the Huawei Mate X6 Triple-Network Satellite collector's edition, which were also satellite communication terminal equipment. It was the world's first popular smart phone that supported triple-network satellite communication. It could communicate with the outside world through Tiantong Satellite Communication, Beidou Satellite News, and low-orbit satellite Internet.(The low-orbit satellite internet system was being tested and was expected to open in the second half of 2025.) It could realize communication functions such as sending edited text messages, receiving text messages, sending picture messages, sending positioning and action trajectories composed of positioning, making and receiving satellite phones, satellite pagers, and so on. Glory had also made a breakthrough in satellite communications technology. The results could be applied to future smart terminal devices (such as Glory Magic6), enabling them to have satellite communications capabilities. The antenna size, power consumption, and communication stability were optimized, entering the era of "ground + satellite" dual communications. In addition, there were satellite communication terminal devices such as the Beidou satellite positioning smart badge on the market, as well as small satellite Mobile device such as satellite phones. They were relatively cheap and could allow ordinary mobile phones to have satellite phone functions. In terms of basic composition, the main units of the satellite terminal, including the satellite transmission unit, image coding unit, voice coding unit, etc., can all be combined in a portable box. The terminal provides a rich data interface for computers, cameras and other external devices to access the terminal. Its radio frequency output and input can be different frequency bands, which can be adapted to various mainstream antenna units at home and abroad. The satellite communication portable terminal could provide users with a portable multi-service satellite communication platform, so that users could easily establish satellite communication links with the command center or other terminal to transmit images, voice, data and other services, no matter where they were. It mainly provided satellite phones, image acquisition and transmission, two-way video calls, file transmission, remote network access, data transmission and other functions. In the military, the miniaturized satellite communication terminal could be operated by a single soldier or in the form of a vehicle. It could be used in the L-band (1 to 2 gigaHertz), X-band (8 to 12 gigaHertz), Ku-band (12 to 18 gigaHertz), and Ka-band (26.5 to 40 gigaHertz). "A Short History of the Future: Legends of the Intelligent Era" was equally exciting. Everyone was welcome to click and read it!

Take Beidou Messenger as an example. It was priced at 999 yuan, including three-year fees (including 1500 free communication services). The initial discount price was 799.1 yuan. In 2024, there was a 50% discount on Double Eleven, which was only 399 yuan. Different satellite communication phones or devices may have different charging methods. For example, some mobile phone satellite communication functions are exclusive to top-tier models and need to be purchased at an additional cost, but the specific amount is not available.

There were several ways to apply for a satellite phone card: 1. Travel agency: If you often travel abroad or participate in adventure activities, you can apply for a satellite phone card at the travel agency. Some large travel agencies provided satellite communication services and recommended suitable satellite phone cards according to their needs. 2. [For the operator, go directly to the local telephone business hall for consultation.] Many carriers provided satellite communications services and had a variety of packages to choose from. They could choose the right card according to their needs. 3. Internet platform: Many third-party Internet platforms now provide satellite phone card processing services. You can search for related goods or services on various shopping platforms or online travel platforms. These platforms usually provide detailed product introductions and user reviews in order to choose the right satellite phone card.

Mobile satellite communication has the following uses: 1. ** Emergency SOS **: In situations where there is no ground network signal, such as remote areas (deserts, seas, and mountains), and "signal desert" areas (oceans and forests), you can still send a message for help through mobile satellite communication. For example, the Huawei Mat50 series could send messages through the Changlian App when there was no terrestrial network signal. It could also use Beidou satellite messages to generate trajectories to facilitate the positioning of rescuers. 2. ** Make up for the lack of network signal coverage of the operator **: ensure that mobile phones can still talk and send text messages in areas where the ground network signal cannot cover, so that the communication in remote areas can be improved. 3. ** Commercial marketing and brand promotion **: For mobile phone manufacturers, satellite communication is a differentiated function. It can bring topics to the product, help improve the brand image, show their technical strength, and win more market share. 4. ** Realizing global information communication **: Theoretically, it can achieve true global communication and eliminate signal blind spots.

There were many differences between satellite communication phones and ordinary phones: 1. ** Call signal **: Satellite communication phones transmit signals directly to the satellite for communication, while ordinary phones transmit signals to the ground base station for directional transmission. 2. ** Signal Search **: Normal cell phones will automatically search for signal networks when turned on. Satellite communication cell phones need to search for satellite networks. 3. ** antenna **: Satellite communication mobile phones need a long antenna to receive signals. The antenna of ordinary mobile phones cannot be seen. 4. ** Function **: Satellite communication mobile phones are mainly functional and do not have entertainment functions. Ordinary mobile phones have various functions, including entertainment functions. 5. ** Communication quality **: Satellite communication mobile phones are not affected by natural disasters on the ground. The communication quality is stable and the coverage is wide. Ordinary mobile phones may have poor communication quality when encountering natural disasters on the ground. 6. ** Adding an antenna **: Satellite communication mobile phones generally need to be equipped with an outdoor antenna to receive signals stably. Ordinary mobile phones do not need it.

Puyi Eyewear was a high-end eyewear brand founded in Hong Kong. Its price was higher because it was of very high quality, and the materials and craftsmanship used were very exquisite. Pu Yi glasses were designed, produced, and sold by brand manufacturers, so the price was much more expensive than ordinary glasses. Pu Yi Glasses cooperated with many internationally renowned brands to provide high-quality products and services, as well as a luxurious experience. Its stores provided a personalised service, selecting matching styles for each customer, and providing a series of shopping experiences and VIP services. Mr. Qiu Zijie, the founder of Puyi Glasses, shared his experience and ideas in brand management, product selection, and service content. Pu Yi Glasses was based on the personalisation and advanced optometrification and eye protection technology, providing perfect answers for every pair of eyes. Puyi Glasses had been in the market for 18 years and had become the leader of the luxury glasses market.

The hood was a device installed at the front of the camera lens, digital camera, and video camera. It was an important part of the lens optical system. Its main uses included: 1. ** Suppression of stray light **: avoid glare and improve image clarity and color reproduction. In different light positions such as backlighting, side backlighting, forward lighting, side lighting, lighting photography or night photography, it can prevent non-imaging light, surrounding scattered light or interference light from entering the lens, avoid fog and halo phenomena, and improve the color saturation and clarity of the picture. 2. ** Protect the lens **: When the lens is accidentally dropped, it can help reduce the damage caused by the fall; it can prevent fingers from accidentally touching the surface of the lens; it can also block the sand, rain, snow, etc. to a certain extent to prevent other things from directly touching the surface of the lens. In terms of usage, the hood in front of all the lenses had been carefully calculated by the manufacturer to help improve the quality of the shot. If the lens was equipped with a crystallizer, although the crystallizer and the hood had no similarities, the hood still needed to be installed. When rotating the crystallizer, the hood could be turned upside down and buckled on the lens, or temporarily removed and placed in the camera bag. It was not necessary to buy the original hood. Buying a hood that matched the lens 'caliber and angle of view could play its role. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

The following is some common optical parameters on the lens: 1. ** effective focal length (EFL)**: The distance from the center of the lens to the focal point. It could be divided into image focal length (the distance between the main surface of the image and the focal point of the image) and object focal length (the distance between the main surface of the object and the focal point of the object). If the focal length is too short, it will cause the field of view to be too large, causing distortion, difficulty in controlling the angle of the chief ray, low contrast, serious lens bending, difficulty in correcting the phase difference, and other problems. If the focal length is too long, the lens will be too long, which is not conducive to the miniaturized system. Moreover, the field of view is too small to meet the user's needs (FoV>60°). 2. ** Total length of lens (TL)**: It is divided into optical length (the distance between the first surface of the lens and the image surface) and mechanism length (the distance between the end of the lens barrel and the image surface). 3. ** Back focal length (BTL)**: The distance from the last side of the lens in the optical system to the image plane. 4. ** Front focal length (FFL)**: The distance from the first surface of the lens to the object surface in the optical system must be distinguished from the back focal length of the mechanism. 5. ** Mechanical back focal length (FTL/FFL)**: The distance from the last mechanical surface of the lens group to the image surface. 6. ** Field of View (FoV)**: The largest field of view that the camera can capture. It can be divided into diagonal field of view (FoV-D), horizontal field of view (FoV-H), and vertical field of view (FoV-V). The diagonal field of view is the largest, followed by the horizontal field of view, and the vertical field of view is the smallest. The so-called field of view refers to the diagonal field of view of the digital camera module. The size of the field of view was related to the focal length. Generally, the larger the field of view, the shorter the focal length. 7. ** Joules (F/NO.)**: It was the ratio of the effective focal length to the diameter of the pupil, which was used to determine the brightness of the lens. Under the premise of ensuring the same aperture, the shorter the focal length, the smaller the relative aperture should be. In general, the smaller the F/#, the larger the aperture. 8. Distortion: It is the off-axis phase difference. It is the height difference between the intersection point of the off-axis point and the main ray on the image plane and the ideal (paraxial-like) image plane. It is a function of the field of view and has nothing to do with the aperture. Distortion was divided into TV distortion and optical distortion. TV distortion was further divided into pillow type and cylinder type. Distortion is the image quality that users can easily feel. Different application scenarios have different requirements for distortion. For example, Optical-Distortion <3% is not easy to detect by the human eye, and the objective lens generally requires Optical-Distortion <2%. 9. ** relative illumination (Ri)**: The ratio of the central illumination to the peripheral illumination. If the contrast was too low, the center of the image would be bright and the surroundings would be dark (vignette phenomenon, commonly known as dark corners), which would also cause color distortion. The Ri is directly proportional to COS4 (semi-fov). Different semi-fov correspond to different theoretical values of the Ri. When the Ri<50%, the human eye can distinguish it. In serious cases, the four corners of the picture will be completely black. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

The optical parameters of the camera included the following aspects: 1. ** focal length **: This is a very important optical parameters of the lens. It refers to the distance from the main point of the lens to the focal point. It is an important performance indicator of the lens. The length of the focal length of the lens was inverse to the size of the image taken by the lens. That is, under the same object distance, the larger the focal length of the lens, the smaller the size of the image taken. Most industrial cameras use fixed-focus lenses in practical applications. Before choosing the focal length of the lens, you need to know the object distance of the on-site camera (the installation height of the camera lens from the surface of the measured object) and the field of view of the camera (the size of the characteristics of the measured object). In some applications involving the mixed inspection of objects at different heights, the use of a variable focal length lens would be considered. However, the variable focal length lens had two issues to consider: zooming speed and lens life. 2. ** Depth-of-field **: When the focal length of the lens is adjusted to a focal point, only the objects within a certain distance before and after the focal point are clearly visible. The objects outside this distance are blurred. This distance is the depth of field of the lens. 3. ** Pieces and resolution **: Pieces are the smallest unit of an image generated by the imaging chip, such as a 2-million-pel image. The resolution referred to the imaging ability of the CCD-or CMOS-chip. For example, the resolution of a 2-million-pel camera was 1626 x 1236, which meant that the camera had 1626 x 1236 rows in the X-axis direction. The total image taken was about 2 million pel. The detection accuracy could be simply evaluated by dividing the actual size of the image's X-axis by the number of X-axis dots. However, the final detection accuracy was affected by many factors, including the moving speed of the object being measured, light interference, the shape of the object, the contrast of the features, the computing power of the software, and so on. 4. ** Picture element size **: This is also an important optical parameters of the camera. 5. ** Target size of sensor **: It is the most concerned part of the camera's optical parameters. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>

Seal Optical Character Recognition was a technique that converted the seal text in the image into an edited text. Through this technology, the text on the seal could be easily extracted for subsequent processing and analysis. The steps of Optical Character Recognition include image pre-processing, seal position detection and seal content recognition. In the image pre-processing stage, you can use the openLV library to perform operations such as adjusting the image size and gray-scale processing. The seal position detection needed to locate the position of the main body of the seal, and the target detection method of deep learning could be used. The content of the seal text can be identified using techniques such as curved Optical Character Recognition. The output of the seal recognition system included the coordinate frames of all the texts in the seal and the recognition results. The seal recognition technology could be applied to all kinds of seals, including round seals, oval seals, square seals, etc. It supported the recognition of multiple seals and horizontal rotations at different angles. The seal recognition system could be applied to scenarios such as official documents and bills to improve work efficiency and security.