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Analysis of Bit Error Rate Between BCH Code and Convolutional Code in Picture Transmission

In signal transmission processing, when the signal passes through the channel, it increases noise and causes the recovered signal to distort. Error codes can cause errors in the transmission of information. In order to reduce the bit error rate (BER) and improve the accuracy of receiving information at the receiving end, this paper uses BCH code, convolution code two kinds of coding methods, QPSK modulation for transmission, and no parity modulation is required. In the experiment, we change the signal-to-noise ratio of the signal to obtain different signal-to-noise ratio, the error rate corresponding to the different coding methods. By comparing the error rate, it can be concluded that for BCH code, the longer the code, the lower the BER, but the more spectrum resources will be used. For signals with a signal-to-noise ratio greater than or equal to 3dB, the transmission of (7,4) BCH codes is the optimal solution. For convolution code, the more bits the code generator has, the lower the BER. Soft decoding has a lower BER than hard decoding. When the two coding methods are in series, BER decreases.