 |
In radio systems in particular, a major source of interference is from
other users of the radio spectrum. For example, equipment radiating on frequencies close
to the wanted channel can pass through the receiver selection filtering, causing what is
termed adjacent channel interference.
In cellular applications, mobile users in different geographical locations are assigned
the same frequency for their calls, and if they are not separated by sufficient distance, co-channel interference occurs.
In both radio and television, multipath interference is
common, manifest as ghosting on the television screen, caused by signals travelling
by many different paths between transmitter and receiver each with slightly different time
delay.
|