CORDLESS TELEPHONE SYSTEMS prepared at UNIVERSITY OF DAR ES SALAAM

1. GROUP 3:
Name: Reg#:
Paschal, Privatus 2011-04-05855
Richard, Evarist S 2011-04-00142
Nyakia,Thomas 2011-04-02271
Mchwampaka Davies 2011-04-03213
Urassa Richard E 2011-04-00697
Reuben, Elisha 2011-04-05998
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 1

2. CORDLESS means lacking a cord
so cordless of an electrical/electronic appliance means that appliance
requiring no wire leading to an external electricity source because
of a self contained power supply i.e. powered by an internal
battery
 E.g cordless telephone
Cordless telephone is a telephone with a wireless handset that
communicates via radio waves with a base station connected to a
fixed telephone line, usually within a limited range of its base
station (which has the handset cradle).
There are various generations of cordless system
CT0,CT1,CT2,CT3,DECT,PHP.,PACS,PCS and PWTS
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 2

3. PSTN
Fixed Port
(Base
Station)
Wireless Link
Cordless
Handset
CORDLESS SYSTEM CONFIGURATION
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 3

4. • An early standard for
analog cordless
telephony developed in
Europe. Originally CT0
Features;
 Operates in the 916MHz and
960MHz bands over paired
channels 25 kHz wide and
employs Frequency modulation
(FM).
 FDMA and FDD are used to
derive two separate channels,
one downstream and one
upstream each of which is 12.5
kHz wide.
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 4
•Limited in range to approximately
150m.
•It lacks security
•CT1+ was intended as the basis for
public wireless service along lines of
telepoint which operates in the 887MHz
and 932MHz bands over 80 channels 25
kHz wide with one channel per carrier.
•CT1+ employs FDMA and FDD

5. • It employs TDMA and TDD
• It was originally supporting only
outgoing calls,
• Contemporary CT2
implementations support two
way calling
• Does not support handoff, so the
user must remain within the
range of the antenna used to set
up the call
• 10 mW maximum power output
• It uses Gaussian filtered GMSK
• Up to 100 meter (300 ft) range
• CT2 operates in the 864-868MHz
• CT2+, this is an improvement of
CT2 supporting two way calling
and call hand-off which uses
8MHz in the rang 944MHz to
952MHz.
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 5
•A proprietary digital cordless telephone
system developed by Ericsson in 1990 as
a wireless office telecommunication
system (WOTS) for application in high-
density office environments that also
bases on TDMA and TDD at
approximately 8MHz bandwidth starting
from 944MHz.
CT-2 CT-3

6. • Typical CT users were sold a handset and base
station which they could connect to their own
home telephone system. Calls via the home base
station would be routed via the home telephone
line and in this configuration, the system was
identical to a standard cordless phone. When in
range, the user could receive incoming calls.
• E.g In CT-2, when in range user could receive
incoming calls and once out of range, the CT2 user
could find signs indicating a network base station
in the area, and make outgoing calls (but not
receive calls) using the network base station.
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 6

7.  Japanese air interface
standard developed by
the Research and
Development Centre for
Radio Systems (RCR). The
PHS network interface
was specified by the
Telecommunications
Technical Committee of
Japan.
 It offers two –way
communications, data
services and Internet
services.05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 7
•PHS cells are small with
transmission power of base
station a maximum of 500 mW
and coverage about 2km in
LOS
•Uses TDMA/TDD for its radio
channel access method,
•Pi/4 DQPSK modulation at a
channel rate of 384kbps is
used on both forward and
backward links.

8. • Has capability to handover from one cell to another.
This makes PHS suitable for dense urban areas, but
impractical for rural areas, and the small cell size also
makes it difficult if not impossible to make calls from
rapidly moving vehicles.
• It supports seventy-seven radio channels, each 300 kHz
wide. Forty of the channels are designated for public
systems, and the other thirty-seven are used for home
or office use.
• It has low-cost base stations, and it supports "Dynamic
Cell Assignment" system,
• Modern PHS phone support many value-added
services such as high speed wireless data/ Internet
connection (64 kbit/s and higher), WWW access, e-
mailing, text messaging and even color image transfer.
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 8

9. • Were published in 1992. The name has been
replaced by Digital Enhanced Coreless
Telephone .
• DECT is also based on TDMA/TDD.
• DECT is typically implemented as a wireless-
PBX connected to the PSTN.
• it is free wireless operates around 100 meters
outdoor and much less indoor around 50
meters
• Offers both speech and relatively high data rate
transmission capability (<300 kb/s).
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 9

10. • It transmit a signal during
the time slot allocated to it.
• Transmitting signal during
the idle time allows remote
handset to remain
synchronized and be able to
receive a call immediately.
• Output power is around
2mW in idle mode
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 10
• The handset does not
transmit at all during
the idle periods.
• The transmitted power
which results is around
9.5mW in active mode
(during calls) and
virtually zero in idle
mode (most of the
time).
BASE STATION
HANDSET

11. 05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 11

12. • Residential- one base station can be used to
provide in house voice and data transfer
• Office
small office can be serviced by one base station.
Multiple base stations can be configured to
support large office.
• Tele-point also set up for the public places like
in airports
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 12

13. 2G Digital Cordless specifications
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 13

14.  There are very few homes in Tanzania that use
CT2 system due to decline (poor infrastructure)
of landline trunks.
 DECT is much used in many offices like Bank,
Industries and companies.
 PHS Declined due to decreasing costs of full
cellular service.
05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 14

15. 05/22/15 TE412 : GROUP 3, CORDLESS SYSTEM 15