MSAN-108 Zarlink Semiconductor, Inc., MSAN-108 Datasheet - Page 12

• Manufacturer Part Number: MSAN-108
• Description: Applications of The MT8870 Integrated DTMF Receiver
• Manufacturer: Zarlink Semiconductor, Inc.

MSAN-108
A multi-channel repeater system serving a multitude
of user groups may be found to achieve its most
effective performance in the
case, one RF channel is reserved for system
signalling. System operation could be achieved as
follows.
Each mobile plus the repeater system contain a
DTMF receiver, DTMF generator and appropriate
control logic. Mobiles are assigned individual DTMF
I.D. codes and always monitor the signalling channel
when idle. An originating mobile automatically sends
a DTMF sequence containing its own I.D. and the
I.D. of the called party. This is recognized by the
repeater control which retransmits the called party’s
I.D.
handshake indicating to the repeater control that it is
available to accept a call. At this time the repeater
control sends a DTMF command sequence to both
the
instructs their logic circuits to switch to a specific,
available channel.
repeater control could send DTMF sequences to put
both mobiles on
"
A-56
channel-request
CH5 CH4 CH3 CH2 CH1
REPEATER RECEIVE
originating
AUDIO PATHS
The answering mobile returns a DTMF
PROGRAMMING
AND DISPLAY
KEYPAD
TEST/
"
and
"
queue. This arrangement would
Figure 13 - Block Diagram of Control for "Trunked" Repeater System"
hold
If all channels are busy the
"
answering
CH5 CH4 CH3 CH2 CH1
and add their I.D.’s to a
REPEATER TRANSMIT
"
CROSS-
SWITCH
MT8804
trunked
POINT
AUDIO PATHS
4 x 8
mobiles
"
mode. In this
SINGLE CHIP MICROCOMPUTER
RECEIVER
MT8870
SWITCH
CROSS-
MT8804
DTMF
POINT
4 x 8
CONTROL LOGIC OR
which
GENERA-
allow users to access any available frequency and
converse privately instead of being restricted to one
assigned channel which is shared among several
user groups.
As well as an individual I.D., each mobile belonging
to a particular organization could also have a
common group I.D.
messages to be sent to all company mobiles
simultaneously.
DTMF control, messages could be sent to an
unattended vehicle and, at the user’s convenience,
displayed on a readout .
Each radio link either established or attempted would
result in DTMF I.D. codes being sent to the repeater
control. These occurrences could easily be collected
by a computer for statistical analysis or billing
information.
rental payments could be denied access to the
system.
Simplified block diagrams of the control systems for
both the repeater and mobiles are shown in Figures
13 and 14 respectively.
MT5089
DTMF
TOR
Customers who have defaulted on
Since mobiles would be under
RX
PHONE
PATCH
TX
This would allow dispatch
MONITORS
STATION
PERIPHERAL PORT
HOST COMPUTER,
Application Note
DATA LOGGER,
ETC
TO TELEPHONE
EXCHANGE