33 lines
984 B
Plaintext
33 lines
984 B
Plaintext
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Linmodem contains an X11 interface which can be used to monitor the
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modem parameters. It is used for example in v34 testing (lm -m v34). The
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X11 simulation works only in 16 bit mode. If you are interested by
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other screen depths, please implement them :-)
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The function keys are used to change the parameters which are dumped
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on the screen:
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* for V34:
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F1 : dump the brut samples which enter into the modem (at 8000Hz). A
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hamming windowed FFT is done to output the spectral power.
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F2 : dump the echo cancellor parameters (not implemented yet).
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F3 : dump the samples after frequency normalization & symbol timing
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recovery. You have 3 samples per baud for V34. A hamming windowed FFT
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is done to output the spectral power.
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F4 : dump the equalizer filter in both time & frequency domains.
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F5 : dump the QAM points just after the equalizer and phase
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recovery. This graphic can be used to monitor the overall modem
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quality.
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* for V21/V23 tests
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F1: same as V34
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F3: decision samples
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