Consider a standard RF channel over which signals are being transmitted over a 10 MHz bandwidth at 1800 MHz (using OFDM).
- How does the channel's intrinsic attenuation vary over frequency?
- More precisely, the subcarriers OFDM would be communicating over would be doing so over different bands of frequencies within the 10 MHz bandwidth.Would the channel attenuate the subcarriers differently based on whether they lie in the lower/higher frequencies within the bandwidth.
- Is 10 MHz too small a bandwidth to observe any significant variations?
I am not referring to the Doppler spectrum (multi-path propagation) which causes small scale frequency spread and is a property of the physical surroundings, but to the attenuation that results from the medium itself.