Yes, the trace has DC resistance and additional resistance from skin effect and, eventually, surface roughness. This loss is proportional to the length of trace. The effective impedance shown by a TDR has the characteristic impedance plus the length-dependent resistance building up over the trace length.

Yes, the trace has DC resistance and additional resistance from skin effect and, eventually, surface roughness. This loss is proportional to the length of trace. The effective impedance shown by a TDR has the characteristic impedance plus the length-dependent resistance building up over the trace length.