(Redirected from Uplink)
Uplink
An 'uplink' (UL or U/L) is the portion of a
communications link used for the
transmission of signals from an
Earth terminal to a
satellite or to an airborne platform. An uplink is the inverse of a
downlink. An uplink or downlink is distinguished from
reverse link or
forward link.
★ Pertaining to
data transmission from a data station to the headend.
★ Pertaining to
GSM and cellular networks, the radio uplink is the transmission path from the
Mobile Station (Cell Phone) to a
Base Station (Cell Site). Traffic and signalling flows within the
BSS and
NSS may also be identified as uplink and downlink.
Downlink
A 'downlink' (DL) is the link from a
satellite to a ground station.
★ Pertaining to
GSM and Cellular Networks, the radio downlink is the transmission path from a
Base Transceiver Station (Cell Site) to the
Mobile Station (Cell Phone). Traffic and signalling flows within the
BSS and
NSS may also be identified as uplink and downlink.
Forward link
A 'forward link' is the link from a fixed location (e.g., a
base station) to a mobile user. If the link includes a
communications relay satellite, the forward link will consist of both an
uplink (base station to satellite) and a
downlink (satellite to mobile user).
Reverse link
The 'reverse link' (sometimes called a ''return link'') is the link from a mobile user to a fixed base station.
If the link includes a
communications relay satellite, the reverse link will consist of both an
uplink (mobile station to satellite) and a
downlink (satellite to base station) which together constitute a half
hop.
Sources