is the Paging
|What is the Paging System?
Paging Systems are wireless communication systems
that are designed to send brief messages to a subscriber.
Itís a one-way messaging system in which Base Station
send messages to all subscribers. The Paging System
transmits the message also known as Page, along with Paging
System access number, throughout the service area using Base
Station, which broadcast the page on a radio link.
Types of Paging Systems The Paging Systems can be of two types.
Manual Paging System: In a manual paging system,
a message is sent to the paging operator through telephone
call by the caller. The message is then delivers to the pager
through paging network by the operator.
Automatic Paging System: In an automatic paging system,
the incoming requests are automatically processed by the
paging terminal and then this information is delivers to the pager.
Automatic Paging Systems are mostly used.
Messages in Paging Systems One of the following four types
of information messages can be delivered in a Paging System.
Alert Tone Message
Digital String Message
Text String Message
Alert Tone Message: In the alert tone message,
a dedicated telephone number is assigned to the receiver,
which is also known as Tone Pager. The pager is triggered
by dialing the number. To generate tone-type messages,
the advantage of tone paging is that it utilizes a small amount of airtime.
Voice Message: In the voice message, a voice message
can be transmitted in some tone paging systems after the beep.
Digital String Message: In digital string message, the receiver
is a Numeric Pager. The string can be the telephone number of
the caller or a coded message. This coded message is generated
on request of the caller by the paging center and is decoded by a
codebook built into the pager. This type of paging takes less
amount of airtime.
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)
Operation and Maintenance Center (OMC)
Base Station Controller (BSC)
Base Station (BS)
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 customerís database which is stored in terminal
paging can be accessed by the OMC to add or delete
new customerís 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
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