A method for amplifying signals in a carriage and a vehicle-mounted repeater

Abstract

The invention discloses a method for amplifying signals in a compartment and a vehicle-mounted repeater. The method includes that the vehicle-mounted repeater arranged in the compartment obtains current position information of the compartment; and corresponding relation of position information and a frequency point is inquired according to the obtained current position information, and an amplifying frequency point corresponding to the current position information is determined. The amplifying frequency point comprises a switching reference frequency point of a first cell preset in a cell covering a position represented by the current position information and does not comprise a switching reference frequency point of a second cell. A switching area between two first cells with adjacent relation meets set area requirements, and the second cell is a cell in the cell covering the position represented by the current position information, and a switching area between the second cell and the first cell does not meet set area requirements. Signals bored by the amplifying frequency point are amplified according to set amplifying gain. By means of the technical scheme of an embodiment of the method and the vehicle-mounted repeater, signal strength in the compartment of high speed trains and success rate of cell switching are improved.

Description

technical field [0001] The invention relates to the technical field of signal coverage of expressways in the technical field of wireless communication, in particular to a method for amplifying signals in a vehicle compartment and a vehicle-mounted repeater. Background technique [0002] At present, for high-speed road signal coverage technology, due to the characteristics of fast speed and good airtightness of high-speed trains, its impact on network quality mainly has the following factors: [0003] The first aspect: the good airtightness of the car body causes the additional penetration loss to increase when the signal enters the compartment. The specific increase is related to different models. The attenuation of the signal in a closed compartment may even exceed 24dB. [0004] The second aspect: high-speed operation causes the signal strength at the handover edge of the cell to increase. According to the calculation of a typical propagation model, the signal strength at...

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Problems solved by technology

[0003] The first aspect: the good airtightness of the car body causes the additional penetration loss to increase when the signal enters the compartment. The specific increase is related to different models. The attenuation of the signal in the closed compartment will even exceed 24dB

[0004] The second aspect: high-speed operation causes the signal strength at the handover edge of the cell to increase. According to the calculation of a typical propagation model, the signal strength at the handover edge is required to reach -62dBm (outside the car)

[0006] At present, for high-speed road signal coverage, taking high-speed railways as an example, most of them adopt the form of urban and rural base stations taking into account the coverage of base stations along the railway, which can meet the coverage requirements at low speeds, but after speeding up due to the existence of the above factors, it often cannot meet the requirements. Expressed as:

[0007] The first aspect: the coverage depth does not meet the requirements, and the signal strength of the switching edge cannot meet the requirements of -62dBm (outside the vehicle body)

[0008] The second aspect: Cell reselection and handover are chaotic. Due to the insufficient length of the handover area, cell reselection and handover lag behind the signal attenuation speed, resulting in the inability to occupy the strongest signal and further deteriorating the coverage effect

[0013] Second: The private network can be regarded as an independent network. Through the setting of the neighborhood of the community, only the entrance and exit of the private network and the large network are set up in the station area. All switching and reselection are only carried out within the private network; while the adjustment of the existing network reduces the relationship with the neighbors of the external network, but generally retains the main neighbor relationship with the large network community;

[0014] Third: The private network does not absorb large-scale network services at all, but only absorbs services on trains running on high-speed roads; while existing network adjustments also need to absorb services from surrounding large-scale networks to a certain extent

[0020] First: The private network structure only has an entrance and exit to the large network in the station area. If the station cannot enter the private network community, it will be difficult for mobile terminals to enter the private network during train operation, resulting in poor signal quality for a long time;

[0021] Second: The private network has higher requirements on the coverage quality. Once the mobile terminal is disconnected from the private network (such as dropped calls, etc.), it will be difficult to re-enter the private network, resulting in poor signal quality for a long time;

[0022] Third: If the mobile terminal on the periphery of the expressway chooses a private network signal, then when the mobile terminal leaves the coverage of the expressway, since the private network does not have a large network adjacent relationship, disconnection and call drop will occur

If the base station (including repeater) outside the carriage is used to cover the mobile terminal in the carriage, it is necessary to use a very large power transmission of the base station to meet the coverage and switching requirements. In addition to energy saving and environmental protection factors, the high-intensity signal outside the carriage will The electromagnetic environment along the highway causes very large interference

And usually these base stations use dedicated frequencies, resulting in a waste of frequency resources

[0028] Second, the strict control of private network signals limits the use of private network coverage technology, because it is difficult to restrict the propagation of wireless signals in open spaces, and it cannot prevent mobile terminals around expressways from entering the private network signal coverage area

However, the repeater is only responsible for amplifying the signal. Although it improves the signal strength in the car, it cannot increase the length of the handover area of ​​the adjacent cell, and cannot solve the problem of cell reselection and handover confusion caused by the insufficient length of the handover area. It cannot independently solve the signal coverage of the expressway, but belongs to the means of adjusting the existing network. The vehicle repeater is used as an auxiliary method to strengthen the signal power of the base station

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