Frequency selection device and method based on WIA-PA protocols

Abstract

The invention relates to a frequency selection device based on the WIA-PA protocols. The frequency selection device comprises a double-path phased-locked loop unit, an MCU and an RF narrowband filtering and amplification unit in sequential connection, the double-path phased-locked loop unit is connected with the RF narrowband filtering and amplification unit, and the RF narrowband filtering and amplification unit is also connected with an antenna and a modem. The frequency selection method comprises that when the MCU receives a switching command from a host computer, and the double-path phased-locked loop unit is configured to output first local oscillation and second local oscillation; after the model emits a reception trigger signal, first and second RF switches are switched to a reception link, and the reception link is powered on; and the RF narrowband filtering and amplification unit carries out low-noise amplification on a received RF signal, primary frequency mixing is carried out on the RF signal to generate an intermediate-frequency signal, the intermediate-frequency signal is filtered and amplified, secondary frequency mixing is carried out on the filtered and amplified intermediate-frequency signal so that the intermediate-frequency signal is recovered to an RF signal, and the recovered RF signal is amplified and then output by the switch RF switch. Interference of WLAN signals can be effectively filtered by increasing intermediate-frequency filtering in the reception link, the device reception sensitivity is improved, and the transmission distance is increased.

Description

Technical field [0001] The invention belongs to the field of industrial Internet of Things, and specifically is a WIA-PA anti-interference device and method applied in an industrial control system. Background technique [0002] WIA-PA industrial wireless network uses the 2.4GHz free frequency band. There are WLAN and Bluetooth devices in the 2.4GHz free frequency band, causing serious interference to WIA-PA wireless devices, especially WLAN interference. At present, the three major operators have For large-scale commercial use of WLAN, in order to ensure the download speed, the signal strength must be guaranteed. At present, the radio frequency transmission power of outdoor WLAN base stations is generally 2W. In addition, the interference of private wireless routers and wellhead monitoring wireless cameras on WIA-PA cannot be ignored, causing WIA- The receiving sensitivity of the PA device is reduced, and the data transmission is unstable. Summary of the invention [0003] The pu...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to overcome the deficiencies in the anti-interference ability of the existing WIA-PA receiving chip, and solve the device and method for coexistence with other networks in the 2.4GHz free frequency band

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