Text String Message:
In the text string message, the receiver is an
Alphanumeric Pager, which has large screen to display the text
strings. This type of messaging is becoming more popular than
numeric messaging.
Paging System Architecture
The Paging System network consists of six basic elements.
-
User Terminal
Equipment (Input Devices)
-
Paging
Terminal
-
Operation and
Maintenance
Center (OMC)
-
Base Station
Controller (BSC)
-
Base Station
(BS)
-
Pager
User Terminal Equipment (Input Devices):
Terminal
equipment is used by the caller to send messages. The equipment can
be a telephone handset, a computer with modem and a specific input
device. A telephone handset is used to generate alert tone or
numeric type messages and is delivered through the Public Switch
Telephone Network (PSTN), while alphanumeric messages are generated
by the computers and are delivered through the Public Switch Digital
Network (PSDN).
Paging Terminal:
The messages are sent to the paging terminal through user
access interface. A paging terminal can supports 1 million pagers
and is connected to a central office of PSTN. The paging terminal
also maintains a database of the customer which conations
information such as page number, pager code etc.
Operation and
Maintenance
Center (OMC):
The OMC is used
for operation, administration and maintenance functions of a paging
network. The customer’s database which is stored in terminal paging
can be accessed by the OMC to add or delete new customer’s records.
Base Station Controller (BSC):
The paging
terminal and base stations are connected by the BSC by powering up
the base stations. In transmitting mode, the BS consumes the high
power and when it is in idle mode it consumes low power.
Base Station (BS):
The messages to the pager are broadcasted by the BS over
radio links. The BS and its pagers have dedicated paging channels.
The messages from the paging terminal to the BS are transmitted by
using transmission technologies, which are leased telephone lines
and satellite based networks.
Pager:
A pager includes four basic elements.
-
A Receiver:
To receive and demodulate the paging signals, the receiver is
tuned to the same radio frequency (RF) as the BS.
-
A Decoder:
The binary information is decoded by the decoder.
-
A Control
Logic:
The control logic provides control for duplicate messages,
locking messages and freeze messages.
-
A Display:
A display is used to read messages.
Paging Systems have ultra-reliable coverage, high infra
structure, high complexity and high hardware cost.
COMPUTER TIPS