3 formatting list of questions

I need to output a data stream at 40 kbit/s$$40\textrm{ kbit/s}$$ or faster out of a computer system whose only accessible output peripheral is the audio interface. This interface has reasonable specs, 96 kHz$$96\textrm{ kHz}$$ sample rate, with 24$$24$$-bit$$\textrm{bit}$$ resolution, but the output stage is AC-coupled. Only one output channel is available. A good assumption would be that it behaves like a band-pass filter with a 4Hz$$4\textrm{ Hz}$$ to 40kHz$$40\textrm{ kHz}$$ pass-band with less than -1dB$$-1\textrm{ dB}$$ attenuation; and that it has a 90dB$$90\textrm{ dB}$$ SNR. I don't have any other complexity constraint on the emitter.

I do not expect additional noise / attenuation on the cable connecting the emitter to the receiver.

The receiver is an embedded system with a 120 MHz$$120\textrm{ MHz}$$ Cortex-M3 MCU. If necessary, similar audio acquisition performance can be assumed. An additional dedicated demodulation chip (if there exists such a thing for such low frequencies) could be an option.

Which digital modulation scheme would be suitable for this situation? Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel? Are there existing applications with similar constraints at which I could look for inspiration?

• Which digital modulation scheme would be suitable for this situation?
• Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel?
• Are there existing applications with similar constraints at which I could look for inspiration?

I need to output a data stream at 40 kbit/s or faster out of a computer system whose only accessible output peripheral is the audio interface. This interface has reasonable specs, 96 kHz sample rate, with 24-bit resolution, but the output stage is AC-coupled. Only one output channel is available. A good assumption would be that it behaves like a band-pass filter with a 4Hz to 40kHz pass-band with less than -1dB attenuation; and that it has a 90dB SNR. I don't have any other complexity constraint on the emitter.

I do not expect additional noise / attenuation on the cable connecting the emitter to the receiver.

The receiver is an embedded system with a 120 MHz Cortex-M3 MCU. If necessary, similar audio acquisition performance can be assumed. An additional dedicated demodulation chip (if there exists such a thing for such low frequencies) could be an option.

Which digital modulation scheme would be suitable for this situation? Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel? Are there existing applications with similar constraints at which I could look for inspiration?

I need to output a data stream at $$40\textrm{ kbit/s}$$ or faster out of a computer system whose only accessible output peripheral is the audio interface. This interface has reasonable specs, $$96\textrm{ kHz}$$ sample rate, with $$24$$-$$\textrm{bit}$$ resolution, but the output stage is AC-coupled. Only one output channel is available. A good assumption would be that it behaves like a band-pass filter with a $$4\textrm{ Hz}$$ to $$40\textrm{ kHz}$$ pass-band with less than $$-1\textrm{ dB}$$ attenuation; and that it has a $$90\textrm{ dB}$$ SNR. I don't have any other complexity constraint on the emitter.

I do not expect additional noise / attenuation on the cable connecting the emitter to the receiver.

The receiver is an embedded system with a $$120\textrm{ MHz}$$ Cortex-M3 MCU. If necessary, similar audio acquisition performance can be assumed. An additional dedicated demodulation chip (if there exists such a thing for such low frequencies) could be an option.

• Which digital modulation scheme would be suitable for this situation?
• Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel?
• Are there existing applications with similar constraints at which I could look for inspiration?
2 added 9 characters in body

I need to output a data stream at 40 kbit/s or faster out of a computer system whose only accessible output peripheral is the audio interface. This interface has reasonable specs, 96 kHz sample rate, with 24-bit resolution, but the output stage is AC-coupled. Only one output channel is available. A good assumption would be that it behaves like a band-pass filter with a 4Hz to 40kHz pass-band with less than -1dB attenuation; and that it has a 90dB SNR. I don't have any other complexity constraint on the emitter.

I do not expect additional noise / attenuation on the cable connecting the emitter to the receiver.

The receiver is an embedded system with a 120 MHz Cortex-M3 MCU. If necessary, similar audio acquisition performance can be assumed. An additional dedicated demodulation chip (if there exists such a thing for such low frequencies) could be an option.

Which digital modulation scheme would be suitable for this situation? Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel? Are there existing applications with similar constraints at which I could look for inspiration?

I need to output a data stream at 40 kbit/s or faster out of a system whose only accessible output peripheral is the audio interface. This interface has reasonable specs, 96 kHz sample rate, with 24-bit resolution, but the output stage is AC-coupled. Only one output channel is available. A good assumption would be that it behaves like a band-pass filter with a 4Hz to 40kHz pass-band with less than -1dB attenuation; and that it has a 90dB SNR. I don't have any other complexity constraint on the emitter.

I do not expect additional noise / attenuation on the cable connecting the emitter to the receiver.

The receiver is an embedded system with a 120 MHz Cortex-M3 MCU. If necessary, similar audio acquisition performance can be assumed. An additional dedicated demodulation chip (if there exists such a thing for such low frequencies) could be an option.

Which digital modulation scheme would be suitable for this situation? Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel? Are there existing applications with similar constraints at which I could look for inspiration?

I need to output a data stream at 40 kbit/s or faster out of a computer system whose only accessible output peripheral is the audio interface. This interface has reasonable specs, 96 kHz sample rate, with 24-bit resolution, but the output stage is AC-coupled. Only one output channel is available. A good assumption would be that it behaves like a band-pass filter with a 4Hz to 40kHz pass-band with less than -1dB attenuation; and that it has a 90dB SNR. I don't have any other complexity constraint on the emitter.

I do not expect additional noise / attenuation on the cable connecting the emitter to the receiver.

The receiver is an embedded system with a 120 MHz Cortex-M3 MCU. If necessary, similar audio acquisition performance can be assumed. An additional dedicated demodulation chip (if there exists such a thing for such low frequencies) could be an option.

Which digital modulation scheme would be suitable for this situation? Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel? Are there existing applications with similar constraints at which I could look for inspiration?

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# Which digital modulation scheme would be suitable for transmitting digital data through the output of a PC soundcard

I need to output a data stream at 40 kbit/s or faster out of a system whose only accessible output peripheral is the audio interface. This interface has reasonable specs, 96 kHz sample rate, with 24-bit resolution, but the output stage is AC-coupled. Only one output channel is available. A good assumption would be that it behaves like a band-pass filter with a 4Hz to 40kHz pass-band with less than -1dB attenuation; and that it has a 90dB SNR. I don't have any other complexity constraint on the emitter.

I do not expect additional noise / attenuation on the cable connecting the emitter to the receiver.

The receiver is an embedded system with a 120 MHz Cortex-M3 MCU. If necessary, similar audio acquisition performance can be assumed. An additional dedicated demodulation chip (if there exists such a thing for such low frequencies) could be an option.

Which digital modulation scheme would be suitable for this situation? Are there already code libraries (software defined radio libs?) that would prevent me from reinventing the wheel? Are there existing applications with similar constraints at which I could look for inspiration?