Multiple-antenna based mobile communication method for high-speed train

Abstract

The present invention provides a multiple-antenna based mobile communication method for high-speed train. The method comprises following steps: when a high-speed train is running in a high speed on a straight section, a mobile station connecting a directional antenna and establishing connection with base stations in the radiation range of the directional antenna; the mobile station computing the offset of the transmission and receiving frequencies thereof according to the speed data transferred from a speed sensor of the high-speed train and conducting frequency compensation; the mobile station conducting the switching between base stations in the radiation range of the directional antenna according to the change in the intensity of received base station signals and the serial number of the base stations; real-time displaying the signal intensity between the mobile station of the high-speed train and various connected base stations, the numbers of the base stations and the connection state. The present invention can realize connection between the mobile station of the high-speed train and multiple base stations at the same time, greatly reduce the Doppler shift caused by the relative motion between the mobile station and base stations, ensure reliable, continuous massive data transmission and have high engineering application value.

Description

technical field [0001] The invention relates to a high-speed rail mobile communication method, in particular to a high-speed rail mobile communication method based on a composite antenna. Background technique [0002] In recent years, with the rapid development of my country's high-speed railway, high-speed railway has become an important means of transportation for people's daily travel, providing convenience for people's life and work, but at the same time there are many technical problems, real-time and effective communication of high-speed trains has become a Technical problems that need to be solved urgently. Since mobile communication was mainly used at low mobile speeds in the past, the Doppler effect involved when the speed of the transmitting signal source and the receiving signal source is not synchronized is not obvious, and it can be adjusted with a simple algorithm. If the existing mobile communication technology is directly applied to the high-speed rail, there...

AI Technical Summary

Problems solved by technology

[0005] The receiver at the high-speed rail terminal is instantly affected by twice the maximum Doppler frequency shift, which affects the time and reliability of switching and reconnecting, and is prone to disconnection

At the same time, because the value of θ frequently changes between 0°, 90°, 180°, 0°, 90°, 180°..., resulting in f d is also changing frequently. For OFDM systems, f d Frequent large changes will greatly affect the orthogonality between carriers, resulting in a decrease in synchronization performance and an increase in the bit error rate, which is difficult to solve with existing algorithm software algorithms

[0006] 2. The data transmission time between the high-speed rail mobile station and the base station is limited

[0007] Assuming that the distance between base stations next to the existing high-speed rail is calculated as 3 kilometers, and the high-speed rail travels 3 kilometers, it switches with the base station once. If the speed of the high-speed rail is calculated at 300 km / h, the switching interval is 36 seconds. After deducting the switching connection time, the remaining transmission data time will be will be greatly affected

[0008] 3. Unable to form a multi-line connection between the mobile station and the base station

[0009] In traditional mobile communication, the connection between the mobile station and the base station is "single thread", that is, the high-speed rail mobile station does not connect and transmit data with two or more base stations at the same time, which is obviously not suitable for high-speed railway applications

Images