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has been cited by the following article:

• TITLE: Performance Comparison of Three Algorithms Applied to UM2000 Signal Demodulation

  AUTHORS: Zhichao Qiao, Fuping Wang

  KEYWORDS: UM2000 Signal; Differential Frequency Detection; Zero-Crossing Detection; Quadrature Demodulation

  JOURNAL NAME: Journal of Signal and Information Processing, Vol.4 No.3B, October 16, 2013

  ABSTRACT: UM2000 signal is a type of multi-audio frequency-modulated signal which is widely used for railway blocking. Principles of three typical demodulating algorithms are presented in details in this paper. Bit error rates of the three methods at different SNRs are achieved by Monte Carlo simulation experiments. Among the three algorithms, the quadrature demodulation has the best performance at the real working environment. However, the three methods have the same problem of phase hopping when noise is too strong.