How far can you go until the losses are over 160 dB? Reason I'm asking is that LTE Cat-M (low-bandwidth IoT) go that low, or lower [0]. GLONAS (GPS) receivers deal with over 180 dB of loss [1]. It depends on the power level in the transmitter, and how well the receiver can lock on to very faint, but expected, patterns in the noise. One of the tricks is to re-transmit, sometimes literally thousands of times.

[0] https://www.altair-semi.com/wp-content/uploads/2017/02/Cover...

[1] https://en.wikipedia.org/wiki/DBm -- Satellites transmitting +55 dBm, receivers seeing -127 dBm.