Bluetooth signal sending and receiving tws earbuds keep disconnecting

The process of Bluetooth sending and receiving signals. Carrier modulation is performed on the data before transmission, and the received high-frequency signal is demodulated after reception. The process of sending and receiving data in bluetooth In , valid data information and control information are transmitted on the channel at the same time, and they use their own interfaces respectively. Among them, the data information is sent to the space or received from the space: the control information is used to control the whole set of actions of the wireless radio frequency transceiver. In the whole set of control actions, the information mainly controlled by the control information during transmission includes the adjustment of the carrier frequency of the transmitter, the power level of the transmission, and the bit (bit) flow of the data information. bjbjaudio.com   <a style="opacity:0.0;color:#ffffff">tws earbuds keep disconnecting</a>

When receiving, the control information mainly controls the receiving procedure of the data stream, the demodulation after receiving the signal, the strength of the received information, the scientific and medical frequency bands, and there is unpredictable interference at any time during the communication process. In order to ensure the normal operation of the positive Bluetooth device without interference, the Bluetooth specification adopts the "frequency hopping" technology to ensure stable transmission. Frequency hopping technology divides the frequency band into several "frequency hopping channels". In the process of communication , the radio transmitter and receiver continue to hop from one channel to another according to the time and method code sequence agreed upon by both parties. It is random, and it is impossible to interfere with Bluetooth according to the same law of frequency hopping. This technology of constantly hopping channels is called frequency hopping technology. bj bjaudio.com

The Bluetooth signal transmission distance is closely related to the power of the Bluetooth transmitter: the greater the power, the more radiated the farther away. For example, the emission distance of 100mW is 100m, the emission distance of 2.5mW is 10m, and the emission distance of 1mW is 10cm. bjbjaudio.com            <a style="opacity:0.0;color:#ffffff">tws earbuds keep disconnecting</a>

Bluetooth modulation method
The modulation method used for Bluetooth radio signals is Gaussian Filter Frequency Shift Keying GFSK. GFSK high FSK modulation is to filter the input signal through a Gaussian low-pass filter, perform appropriate phase integration operation, and multiply the in-phase and quadrature components of the carrier respectively, which is equivalent to pre-modulation and then FSK modulation. The advantage of this modulation method is that it can not only maintain a constant amplitude, but also control the spectrum of the modulated signal by changing the 3dB bandwidth of the Gaussian low-pass filter. Desired characteristics of a communication system. bjbjaudio.com             <a style="opacity:0.0;color:#ffffff">tws earbuds keep disconnecting</a>