High-speed rail mobile terminal uplink transmission method based on directional antenna

Abstract

The invention discloses a high-speed railway mobile terminal uplink transmission method based on a directional antenna, and mainly aims to solve the problem of short uplink transmission distance of ahigh-speed railway mobile terminal in the prior art. According to the technical scheme, the method comprises the following steps: acquiring the position information and posture information of the directional antenna through a built-in GPS (Global Positioning System) of high-speed railway mobile terminal UE (User Equipment) and antenna posture information sensing equipment by means of the definiteness of a high-speed railway mobile terminal running rail; acquiring the position information and the posture information of the directional antenna at a target sector from a base station system message; and adjusting the posture of the directional antenna of the high-speed railway mobile terminal UE according to the acquired antenna information, so that the center normal direction of the directional antenna of the high-speed railway mobile terminal UE in a high-speed moving state is always aligned with the center position of the direction antenna at the target sector, and directional antenna gain is utilized to the maximum extent. Through adoption of the method, the power consumption of the high-speed mobile terminal UE in the uplink transmission process is lowered, and the uplink transmission range of the mobile terminal is enlarged.

Description

technical field [0001] The invention belongs to the technical field of communication, and in particular relates to an uplink transmission method of a high-speed rail mobile terminal based on a directional antenna, which can be used in a high-speed rail mobile communication system. Background technique [0002] High-speed rail is the abbreviation of China High-speed Railway CHSR, which refers to the newly-built passenger-dedicated railway with a design of 250 km / h and above EMU trains and an initial operating speed of not less than 200 km / h; due to its fast economy, good safety and passenger capacity High-end features have been favored since it was put into operation, and its economic benefits are also very considerable; at present, my country's high-speed railway has reached a speed of 350km / h, covering a wide range, and the construction scale is still increasing; under this background, the applicable The development of mobile communication systems for high-speed rail has caus...

AI Technical Summary

Problems solved by technology

Since 2005, long-term evolution LTE has been put into research as a standardization project of 3GPP, which requires the system to achieve better performance, including higher data rate, lower delay, better coverage, and better frequency efficiency And greater mobility support, etc., especially for mobility support, LTE puts forward higher requirements, requiring the system to support a mobile speed of 350km / h, and even support a very high speed of 500km / h in some frequency bands. Mobile speed; the existing LTE technology uses omnidirectional antennas for mobile terminals, so the uplink transmission distance is limited. In the LTE private network deployed by high-speed rail, the coverage distance of each LTE base station is usually 1-2Km, resulting in the communication process. A large number of switching operations are generated, and even frequent disconnections occur, which cannot well meet the business transmission requirements of high-speed rail real-time monitoring

[0003] The high-speed rail monitoring mobile communication system can monitor the movement status of the high-speed rail in real time. It is a mobile communication system to ensure the fast and safe operation of the high-speed rail. Compared with the current commercial mobile communication system, the user distribution of the high-speed rail monitoring mobile communication system is sparse and the amount of data is small. , and the movement speed of the high-speed rail is mostly about 300 kilometers per hour. The traditional cell division method cannot meet its high mobility requirements. By increasing the height of the base station and increasing the coverage distance of each cell under the base station is the solution to the high-speed rail mobile communication problem An effective technology; at present, it is proposed to build LTE base stations on airships above 20Km, so that the coverage radius of a single sector is greater than 100Km, and the high-speed rail mobile terminal is located on the high-speed rail, moving at high speed with the high-speed rail, and reporting the movement of the high-speed rail in real time Information and safety information in the compartment, its running trajectory is determined and its speed is basically constant, which provides convenience for solving the problem of uplink transmission of high-speed rail mobile terminals; however, the existing mobile terminals use omnidirectional antenna technology, and the uplink transmission distance is limited, so Unable to meet the uplink transmission distance requirements with large coverage radius

[0004] Ma Zhijian of Shandong University of Science and Technology's master's thesis "Research and Development of Vehicle-mounted Directional Antenna Stable Tracking Platform" takes the telepresence remote control system as the application background, and researches and develops a set of vehicle-mounted directional antenna stable tracking platform with high speed, high precision and good real-time performance , the platform can offset the interference caused by the long-distance movement of the moving carrier and the angular movement of the carrier, so that the directional antenna of the command station can always automatically point to the mobile station, thereby improving the anti-interference and reliability of wireless image transmission; but the The mobile station in this paper uses an omnidirectional antenna, and the uplink transmission distance is small, which cannot solve the problem of uplink transmission with a large coverage radius in the high-speed rail mobile communication system

[0005] In the patent No. 201020172662.4, the patent titled "An Antenna for Automatic Detection of Azimuth and Elevation Angle" provides an antenna, including an electronic compass installed in the antenna. The electronic compass includes an azimuth sensor, an elevation angle Sensors, multi-channel analog-to-digital converters, microcontrollers and serial communication interfaces; the azimuth and elevation angle sensors are used to detect the azimuth and elevation angle parameters of the antenna, and transmit the azimuth and elevation angle information to the multi-channel analog-to-digital conversion device; the multi-channel analog-to-digital converter is used to perform analog-to-digital conversion on the analog voltage signals generated by the azimuth sensor and the pitch sensor; Serial communication of data; the azimuth and elevation angle of the antenna are transmitted to the background network management or local maintenance terminal through the serial communication interface; The mobile terminal antennas in the commercial network are all omnidirectional antennas, so it cannot improve the uplink transmission range of the high-speed rail mobile terminal UE, and still cannot solve the uplink transmission problem under the large coverage radius in the high-speed rail mobile communication system

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