Radius PDR 121, Installation And Operation Manual

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RADIUS
Product Description
PDR 121
iom_pdr121_04_r02.doc Rev 02 Page 14 (67)
Parity – A one-bit quantity indicating whether the number of 1’s in a word is even or odd.
Peer-to-Peer –
Peer-to-Peer is a communications model in which each party has the same
capabilities and either party can initiate a communication session. Other models with which it might
be compared to, include the client/server model and the master/slave model. In some cases, peer-
to-peer communications is implemented by giving each communication node both server and client
capabilities.
Point-to-multipoint
– is one-way or two-way communications from a central point to a number of
subsidiary points, and vice versa.
Poll –
is a method to check the status of an input line, sensor, or memory location to see if a
particular external event has been registered. The communications control procedure by which a
master station or computer systematically invites tributary stations on a multipoint circuit to transmit
data.
Repeater
– is a device that will repeat serial communications on to the predetermined destination.
Routing of messages –
is the selection of a path or channel for sending a message.
RTU –
is a Remote Terminal Unit that is physically remote from a main station or computer but can
gain access through communication channels.
RSSI
(Received Signal Strength Indication) – a parameter returned from a transceiver that gives a
measure of the RF signal strength between the mobile station and base transceiver station, either
as an uplink or downlink measurement.
SCADA –
(Supervisory Control and Data Acquisition) is a system used in industry to monitor and
control equipment status and provide logging facilities.
Transceiver
– A terminal unit which can both transmit and receive information from a data
transmission circuit.
Unsolicited system
– In an unsolicited response system, the RTU’s generate all reporting
messages required, without beein polled by the master. Typically, such messages report a change
of state or a fault, or simply pass data to the SCADA central host without being polled for the data.
6.1 dBm to W Conversion Table
dBm Watts dBm Watts dBm Watts
0 1 mW 16 40 mW 32 1.6 W
1 1.3 mW 17 50 mW 33 2.0 W
2 1.6 mW 18 63 mW 34 2.5 W
3 2.0 mW 19 79 mW 35 3.2 W
4 2.5 mW 20 100 mW 36 4.0 W
5 3.2 mW 21 126 mW 37 5.0 W
6 4 mW 22 158 mW 38 6.3 W
7 5 mW 23 200 mW 39 8.0 W
8 6 mW 24 250 mW 40 10 W
9 8 mW 25 316 mW 41 13 W
10 10 mW 26 398 mW 42 16 W
11 13 mW 27 500 mW 43 20 W
12 16 mW 28 630 mW 44 25 W
13 20 mW 29 800 mW 45 32 W
14 25 mW 30 1.0 W 46 40 W
15 32 mW 31 1.3 W 47 50 W