High attenuation may lead to the inability to recover the signal on the far end. Signal repeaters may be used on the transmission path to periodically boost the signal strength. Baseband transmission is extremely limited to attenuation. Broadband much less so. In addition, wireless communications is much less susceptible to attentuation that is wireline communications such as xDSL or cable modems.
Crosstalk refers to the interference between channels.
If so, you have experienced the effect of crosstalk. This is because strong signals originating from the near end, can interfere with the weaker signals originating at the far end. Noise may be defined as the combination of unwanted interfering signal sources whether it comes from crosstalk, radio frequency interference, distortion, or random signals created by thermal energy. Noise impairs the detection of the smallest analog levels which may be resolved within the demodulator. The noise level along with the maximum clip level of an analog signal path set the available amplitude dynamic range.