Commit Graph

9 Commits

Author SHA1 Message Date
Andreas Eversberg d2472cfca6 Emphasis: Add filter to prevent emphasis above 4000 Hz
Remove obsolete filter from fsk.c.
2017-09-01 18:42:47 +02:00
Andreas Eversberg ca10048e5c Rename filter -> iir_filter (file name and instance name)
This is useful when using fir_filter in the future.
2017-05-15 21:46:32 +02:00
Andreas Eversberg 7e45f556ce Correcting all levels and move all remaining integer samples to sample_t
The leves are based on the standards of each mobile network. They
are adjusted to the specified frequency deviation now.
2017-02-18 21:01:13 +01:00
Andreas Eversberg bd7ccc5fa0 Add global DC-Filter and remove all individual DC-Filters 2017-02-18 21:01:12 +01:00
Andreas Eversberg 71e556e7ff Work on emphasis filter: Neutral @ 1000 Hz; Use filter before de-emphasis 2017-02-18 21:01:11 +01:00
Andreas Eversberg 7ea3bc188d Move samples of int16_t format to sample_t, that is of type double
This prepares the correction of all levels
2017-02-18 21:01:08 +01:00
Andreas Eversberg 1ea95de120 C-Netz: Use emphasis with 200 uS time constant 2016-10-23 08:46:05 +02:00
Andreas Eversberg 42eefe90bf common code: Fixed de-emphasis by adding high pass filter
This high-pass filter filters out DC and frequencies below 300 Hz.
Now de-emphases will not cause low frequencies to saturate audio level
range or cause too high levels on low frequencies.
2016-05-13 09:37:02 +02:00
Andreas Eversberg 4356c93afa common: Add pre and de emphasis, if the radio does not support it
Connect to the oscillator of the transmitter - good girl!
You need to enable pre emphasis in this case.

Connect to the discriminator of the receiver - good boy!
You need to enable de emphasis in this case.
2016-04-24 15:14:56 +02:00