4RF Limited SRN0400025A ユーザーズマニュアル
About the Radio | 17
Aprisa SR User Manual
Repeater Messaging
The Aprisa SR uses a routed protocol throughout the network whereby messages contain source and
destination addresses. Upon registration, the radios populate an internal neighbor table to identify the
radios in the network. The remote stations will register with a base station, or a repeater, and the
repeater registers with a base station. In networks with a repeater, the repeater must register with the
base station before the remotes can register with the repeater.
destination addresses. Upon registration, the radios populate an internal neighbor table to identify the
radios in the network. The remote stations will register with a base station, or a repeater, and the
repeater registers with a base station. In networks with a repeater, the repeater must register with the
base station before the remotes can register with the repeater.
Additionally, all messages contain a ‘message type’ field in the header and messages are designated as
either a ‘broadcast’ message, originating from a base station, or a ‘unicast’ message, originating from a
remote station.
either a ‘broadcast’ message, originating from a base station, or a ‘unicast’ message, originating from a
remote station.
In a network with a repeater, or multiple repeaters, the base station broadcasts a message which contains
a message type, a source address and a destination address. The repeater receives the message and
recognizes it is a broadcast message, from the message type and source address and re-broadcasts the
message across the network. All remote stations in the coverage area will receive the message but only
the radio with the destination address will act upon the message.
a message type, a source address and a destination address. The repeater receives the message and
recognizes it is a broadcast message, from the message type and source address and re-broadcasts the
message across the network. All remote stations in the coverage area will receive the message but only
the radio with the destination address will act upon the message.
Similarly, the remote station will send a unicast message which contains a message type (unicast) a source
address and a destination address (the base station). The repeater will receive this message; recognize
the message type and source address and forward it to the destination address.
address and a destination address (the base station). The repeater will receive this message; recognize
the message type and source address and forward it to the destination address.
It is this methodology which prevents repeater-repeater loops. If there is repeater (A) which, in some
circumstances, is able to pick up the RF signal from another repeater (B), it will not forward the message
as it will only forward broadcast messages from the base station (recognized by the source address). For
unicast messages the repeater (A) will recognize that the message (from repeater (B)) is not from a
remote with which it has an association and similarly ignore the message.
circumstances, is able to pick up the RF signal from another repeater (B), it will not forward the message
as it will only forward broadcast messages from the base station (recognized by the source address). For
unicast messages the repeater (A) will recognize that the message (from repeater (B)) is not from a
remote with which it has an association and similarly ignore the message.