You can use FM, AM, QAM, or other multi-bit modulation schemes to send that information, but you need to have the signal-to-noise ratio to demodulate it. WiFi

You can use FM, AM, QAM, or other multi-bit modulation schemes to send that information, but you need to have the signal-to-noise ratio to demodulate it. WiFi actually goes up to QAM-1024 (10 bits per symbol) in the more recent specs. However, the SNR you need to decode that is perfectly is something like 35 DB, while recovering a signal that sends 1 bit at a time needs ~3 DB. A 35 DB SNR is very hard to reach unless the RF environment is quiet (basically impossible in an apartment building, for example), but 3 DB is easy. Shannon's limit tells you about the total information capacity of a channel given its bandwidth and SNR. This is usually achieved by using deeper modulation than theoretical, and using error-correcting codes to recover the lost data.