Aiming at the shortcomings of traditional broadcast transmitter noise test methods, such as low efficiency, inconvenient data\nstorage, and high requirements for testers, a dynamic online test method for transmitter noise is proposed. The principle of system\ncomposition and test method is given. The transmitter noise is real-time changing. The Voice Active Detection (VAD) noise\nestimation algorithm cannot track the transmitter noise change in real time. This paper proposes a combined noise estimation\nalgorithm for VAD and dynamic estimation. By setting the threshold of the double-threshold VAD detection to be low, it can\naccurately detect the silent segment. The silent segment is used as a noise signal for noise estimation. For the nonsilent segment\ndetected by the VAD, a minimum value search dynamic spectrum estimation algorithm based on the existence probability of the\nspeech (IMCRA) is used for noise estimation. Transmitter noise is measured by calculating the noise figure (NF).The test method\ncollects the input and output data of the transmitter in real time, which has better accuracy and real-time performance, and the\nfeasibility of the method is verified by experimental simulation.
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