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Approximate communications using Software Radio.
The digital domain allows for much easier recovery of information from coherent systems. Even though radio channels are noisy and fading and difficult to work with, information can be recovered using approximation.
Resources
Setup
Currently, a two-USRP GNURadio setup is being used, with either differential 8-PSK or straight 8- or 16-QAM.
Todo
GNURadio: Feedback (non-feedforward) AGC that doesn't use std::max(), which should be more noise-resistant
Error data using PSK/QAM
Working QAM implementation:
Streaming video
Help, I Don't Have the Permissions to Create a New Page for This
What Steve is doing this week:
Reading about how
DSSS works, used in 802.11b,g to spread the signal in frequency. Open questions are:
Assuming that QAM on GNU Radio is dead, unless a better AGC/phase error calculator works magically, given that we'll have WARP radios soon.
Fighting occasionally with docuwiki syntax