I've just been fooling around with digital radio modes.
I'm just curious about why the audible tone is commonly used to transfer information, rather than the carrier itself?
Are there any data radios that rely on phase shift of the carrier alone?
How hard would it be to detect? Is that the main issue?
The data could be transmitted by reversing the carrier output from the transmitter.
Lets pretent this is the output from a transmitter:
01010101010101010101010101010101010101010101010101
1 is the peak of the waveform, and 0 is the bottom.
Then to transmit data, reverse the carrier every so often"
01010110101010010101010110101011010101001010101101
00000011111111000000000011111111111111100000000111 - binary data
Is there an easy way to detect if the phase has shifted like that?
It seems like that would be the most effective way to transmit data, and use the least amount of bandwidth too.
The transmitter seems like it would be easy to me, just add a circuit to reverse the polarity on demand from a computer signal. The receiver is what I can't fathom how it could work.
I'm just curious about why the audible tone is commonly used to transfer information, rather than the carrier itself?
Are there any data radios that rely on phase shift of the carrier alone?
How hard would it be to detect? Is that the main issue?
The data could be transmitted by reversing the carrier output from the transmitter.
Lets pretent this is the output from a transmitter:
01010101010101010101010101010101010101010101010101
1 is the peak of the waveform, and 0 is the bottom.
Then to transmit data, reverse the carrier every so often"
01010110101010010101010110101011010101001010101101
00000011111111000000000011111111111111100000000111 - binary data
Is there an easy way to detect if the phase has shifted like that?
It seems like that would be the most effective way to transmit data, and use the least amount of bandwidth too.
The transmitter seems like it would be easy to me, just add a circuit to reverse the polarity on demand from a computer signal. The receiver is what I can't fathom how it could work.