ADInstruments S7200 Operation Manual page 169

AD INSTRUMENTS S7200 TV Signal Analyzer Operation Manual
Post-echo scenario
The transmission scenario and the channel impulse response for post-echos are
show in Figure 6-43. In the post-echo scenario, the strongest path (main path) is
from the nearest transmitter tower and the other paths are either from
transmitters located further away or from reflections which arrive after the main
path and have lower power levels. In Figure 6-43, just one echo is shown.
Figure 6-43 Post-echo Scenario and the Associated Channel Impulse Response
Pre-echo scenario
The transmission scenario and channel impulse response for pre-echoes are give
in Figure 6-44. Pre-echoes often occur when there are repeaters nearby. For the
pre-echo scenario, the strongest is re-transmitted from the repeater and doesn't
arrive first. The LOS (line of sight) path arrives first but has a lower power level.
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