A signal frequency calibration method and device for a small base station

Abstract

The invention provides a signal frequency calibration method and device for a small cell. The method comprises the steps of controlling a computer to establish communication connection with a board card of the small cell; carrying out scanning by the computer through a sniffer to acquire a global system for mobile communication (GSM) frequency band in a preset range, and selecting a frequency point in the GSM frequency band as a frequency reference, wherein both a network color code and a base station color code of the frequency point can be identified, and a signal to noise ratio of the frequency point is the highest; and successively approximating a preset frequency precision range through adoption of a Broadcom algorithm according to the frequency reference, thereby carrying out frequency calibration to obtain an automatic frequency control (AFC) voltage value, and storing the AFC voltage value to a calibration file of the board card. According to the method and the device, the frequency offset problem of a small cell product can be solved only through utilization of the computer, the board card does not need to be returned to a factory for reparation due to the frequency offsetproblem, and the outfield maintenance efficiency and precision are improved.

Description

technical field [0001] The present invention relates to the technical field of frequency calibration, in particular to a signal frequency calibration method and device for a small base station. Background technique [0002] Before leaving the factory, each Small Cell (SMC) board must use the 10MHz reference signal output by the Global Positioning System (GPS) as a standard to calibrate the frequency accuracy of the 19.2MHz signal of the board and save it as a calibration file. AFC_INIT value. Due to the difference of hardware, the initial AFC_INIT value of different boards will be different. Therefore, for a newly installed board, frequency calibration must be performed to obtain the AFC_INIT value. [0003] For example, a Long Term Evolution (LTE for short) small base station (LTE Hotspot / indoor, LTE_HI) needs to be synchronized with an existing network base station signal, and the existing network base station uses a Global Positioning System (Global Positioning System, ...

AI Technical Summary

Problems solved by technology

Global System for Mobile Communication (GSM for short), Time Division-Synchronous Code Division Multiple Access (TDS for short), Wideband Code Division Multiple Access (WCDMA for short), Multiple signals such as LTE are completed. However, this method can only be used when the frequency deviation of the board itself is small. If the frequency deviation of the board itself is large, it cannot be synchronized with the external live network macro station.

[0004] In the production process, it was found that after a period of time after the production calibration of the board, due to the influence of the environment, the compensation value after frequency calibration may shift again, and in the use of small base stations, the frequency deviation may occur after a period of time. moved so that the device cannot be used

Although the software can use the built-in synchronization message to synchronize the device, it can only be completed when the frequency deviation is not large. Once the frequency deviation is large or the calibration data is lost, the board must be returned to the factory for repair and frequency deviation calibration Caixing

It can be seen that SMC uses the single tone leaked by the local oscillator for frequency calibration, which needs to be carried out in the factory, but after a period of time, for some reason, some products will have a frequency deviation, so that they cannot be used.

You have to use the RGPS module for synchronization, or return to the factory for repair, which increases the cost

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