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update on freq deviation

Excessive frequency deviation for DMR handsets?

A Hytera DMR handset that I am working with has a frequency deviation of 2300-2700 Hz. This is higher than the expected 1944.0 Hz frequency deviation specified in the DMR specification (ETSI TS 102 361-1). Is it expected that low cost handsets have excessive frequency deviation? I'm wondering how the receiver performs synchronization when the frequency deviation can be so far out of range?

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More info:

  • I/Q samples are collected with an SDR
  • This question is not about carrier frequency offset but rather the FSK frequency deviation
  • To determine the deviation, I used an FM demodulator then measured the distance between minimum and maximum deviation.

Update 1:

  • the frequency deviation is closer to 2100-2400 Hz after further measurement.