Working principle of wireless module

Working principle of wireless module

Introduction to wireless module

Wireless module is divided into wireless analog transmission module and wireless digital transmission module. The early wireless transmission module transmitted analog signals. With the continuous development of wireless technology, wireless analog transmission has been mostly eliminated. At present, the common wireless module transmits digital signals and wireless digital transmission.

The wireless module can transmit any digital information, such as audio, video, image, text, digital, etc. The wireless module can also set up various wireless networks, such as WiFi, ble, GPS, GSM, 3G, 4G, 5g and other networks. We take the wireless module of wireless digital transmission as an example to introduce the working principle of the wireless module in detail.

Wireless module modulation mode

The wireless part adopts frequency modulation, referred to as frequency modulation. It is a modulation method that makes the instantaneous frequency of the carrier wave change according to the change law of the required transmitted signal. It is a modulation method that makes the instantaneous frequency of the modulated wave change with the modulated signal. The circuit to realize this modulation method is called frequency modulator, which is widely used in FM broadcasting, TV sound, microwave communication, phase-locked circuit, walkie talkie, mobile phone and WiFi. The basic requirements for the frequency modulator are large frequency shift, good frequency modulation characteristics and small parasitic amplitude modulation. The radio wave generated by the frequency modulation method is called frequency modulation wave. Its basic feature is that the oscillation amplitude of the carrier remains unchanged and the oscillation frequency changes with the modulation signal. Frequency modulation (FM) means that the frequency of high-frequency carrier is not a constant, but a modulation mode that changes within a certain range with the modulation signal, and its amplitude is a constant.

Working principle of wireless module transmitting part

After the wireless module is powered on, the wireless part first resets the RF IC and waits for the reset to be completed. After the reset is completed, initialize the register, configure the working frequency, configure the transmission power, configure the wireless rate, configure the transmission bandwidth, write the data to be transmitted, enter the transmission state, wait for the transmission to be completed, that is, complete the transmission of one frame of data.

Transmission block diagram:

Working principle of wireless module receiving part

After the wireless module is powered on, the wireless part first resets the RF IC and waits for the reset to be completed. After the reset is completed, initialize the register, configure the working frequency, configure the transmission power, configure the wireless rate, configure the transmission bandwidth, write the data to be transmitted, enter the reception state, wait for the reception interrupt, read the received data in the register, that is, complete the reception of a frame of data.

Receiving block diagram: