This paper introduces an application of QC-LDPC codes to telemetry system. At the same time, a joint design method of code length and telemetry frame length is proposed. Spectrum resources, channel qualities, and hardware capabilities are comprehensively considered in this design method, so that the optimal scheme can be designed. By using the RU encoding algorithm and the LLR BP decoding algorithm, a hardware implementation method based on FPGA and AD936X architecture is proposed. The coding gain of the designed system is simulated according to the technical route. Combining the theoretical analysis and simulation results, it can be seen that of the advantages of low latency and high gain, the proposed telemetry system design method has certain application value in future telemetry systems. In summary, the proposed method solves the problem of high coding delay in traditional telemetry system, and brings about 8 dB coding gain at the cost of minimal delay.