Note: Descriptions are shown in the official language in which they were submitted.
CA 02242296 2002-04-05
METHOD AND APPARATUS FOR PROVIDING PACKET DATA SERVICE
IN A COMMUNICATION SYSTEM
BACKGROUND OF THE INVENTION
1. Field of the IllVent~011
The Present ilwention relates to a data commmiication method in a CDMA
{Code Division Multiple Access) communication system, and in Pwticular, to a
packet data service Providing method.
2. Description of the Related Art
In CDMA of the present communication system and W-CDMA {Wideband-
CDMA) considered as a standard for the next generation communication system,
a packet data communication is implemented with one-to-one continuous
connection established between a terminal and a base station. >3ut it is ideal
that the
one-to-one com~ection between a terminal and a base station lasts as long as
Packet
are exchanged and is released during a Packet data communication suspension
period, so that the capacity of communication channels is efficiently used and
thus
communication cost is saved for users.
A conventional Packet data service in a CDMA communication system
suffers excessive overheads due to the continuous one-to-one connection state
of
commwiication channels dwing a Packet data service, thus decreasiyg use
efficiency of a channel capacity and imposing increased cost on users.
Moreover;
the demands for data service such as PC (Personal Computer) communication and
CA 02242296 1998-10-07
intemet access and mobile communication-based data service are gradually
increasin.~. Most data services are performed in the form. of packet data and
data
is instantaneous rather than always present. That is, most data communications
are
packet data communications.
LJnder this circumstance, there is an ever increasing need for enabling more
subscribers to access a data service at a low expense by subjecting an
interface
structure in the conventional CDMA network to a minimum modification.
FIG. 1 is a block diagram of a ternii.nal, a base station, and a radio l.in.k
in. a
mobile corn~nunication system. The radio link of FIG. .1 is composed of a
forward
channel for data transmission .from the base station to the terminal anal a
reverse
channel for data transmission from the ternainal to the base station.
A conventional CDMA mobile communication system has a forward channel
structure as shown in FIG. 3 and a reverse channel structure as shown in FIG.
2.
Th.e forward CDMA channel. has a pilot channel, a sync channel, a paging
channel,
and a forward traffic channel divided into a fundamental channel and a
supplemental channel. The reverse CDMA channel includes an access chancel and
a reverse traffic channel divided into a fundamental channel and a
supplemental
channel.
A conventional bidirecti.onal traffic channel has too low a bit rate to
provide
a packet data service. An approach to ensuring a bit rate high. enough for the
packet
data service by the conventional bidirectional traffic channel i.s to separate
it into
a .fundamental channel for affording th.e same .function of the conventional
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CA 02242296 1998-10-07
bidirecti.onal tl-affic channel and a supplemental channel for use in. packet
data
communication.
For a packet data service, a call should be maintained between a base station
and a terminal as shown. in FIG. 1 via forward and reverse fundamental
channels.
FIG. 4 is a flowchart of using channels for a conventional packet data
service.
Refen-in~ to FIG. 4, a basic call i.s set up between a terminal. and a base
station using a pilot channel, a sync channel, a paging channel. and au access
channel, in step 411. Here, the basic call is bidirectionally perfornied on
forward
and reverse fundamental channels. In step 412, the base station (terminal)
determines whether a request for packet data tran.smi.ssion has been issued
from the
terminal (base station). In th.e absence of. the packet data tlvansmission
request, the
procedure jumps to step 41.7 in. which the call is maintained on th.e
bidirectional
fundamental charnels.
In the presence of th.e packet data transnussion request in step 412, th.e
base
station (telmilal) notifies the terminal (base station) of use of. a
supplemental
channel on th.e forward (reverse) fiu~damental channel, in step 413, and the
terminal
(base station) sends an acknowledge signal to the base station (terminal.) on
th.e
reverse (forward) fundamental channel, in step 414. In step 415, packet data
i.s
completely transmitted on bidirectional supplemental chancels. Upon
compl.eti.on
of the packet data trallsmission/reception, the bidirectional supplemental
channels
stop their action. in step 416. Then, the call. is maintained on the
bidirectional
fundamental. channels, in step 417.
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CA 02242296 1998-10-07
The above call set-up procedure will be reviewed on tile part of the terminal.
A controller of the temninal. obtains information on a corresponding base
station via
a pilot channel., a sync channel, and a paging chatmel among the .forward
channels
of the base station. Information for access to the base station is generated
by a
message processor of the tetmin.al, converted to a signal by a baseband
processor,
and transmitted to the base station on a reverse access chatmel.
A message processor in. the base station analyses the access information
received ii'om the terminal, gets forward and reverse fimdaln.ental channels
ready,
and seeds to th.e terminal a message indicating that the fundamental. channels
are
ready on the paging channel. The message processor of. the terminal obtains
the
fouward fundamental channel, using the bidirectional fundamental channel
information received from the base station. Then, the tel-minal sends a signal
to the
base station on the reverse fundamental channel in order to allow the base
station
to obtain the reverse fundamental channel. When the base station. succeeds in
obtaining the reverse fundamental channel., it notifies the terminal of the
fact on the
forward fundamental channel. When the base station and the tornainal obtain
the
bidirectional fundamental channels, the call set-up is completed.
Following the call set-up on the bidirectional fundamental ch.ann.els, the
terminal and the base station await packet data transmiss.ion/reception, while
exchanging their information on the bidirectional fundamental channels.
Despite
the absence of transmit/receive packet data, the call. should be maintained on
the
bidirectional fundamental channels. Packet data communication after the call
set-up
is implemented while repeating the procedure shown in FIG. 4.
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FIG. 5 is a state transition diagram of a terminal on th.e basis of a
conventional CDMA standwd. Referring to FIG. 5, when power i.s on in a state 5
1. l,
the terminal is set to an initialization state 512. If the tetmin.al
synchro~~izes its
timing to that of a system in. the i~~i.tiali.zation state 512, it transits to
an. idle state
513. The terminal lnay attempt a call, the base station ti~ansnvts
informatio~.l of the
call attempt to the terminal on a pagiaig channel, and the terminal sends a
page
response message to the base station, in the idle state 513. Then, the
terminal i.s set
to a system access state 514. If the terminal fails to obtain a paging channel
message or is directed from the base station to a different adjacent base
station in
a handoff i..n the idle state 513, the terminal. retut.-n.s to the
initialization state 51.2.
Here, if. the terminal succeeds ui system. access except for the call attempt
or
reception. of a call acknowledge signal in the system access state 51.4, the
terminal.
retmms to the idle state 513. On the contrary, if th.e terminal succeeds in.
the call
attempt or reception of. the call acknowledge signal in the system access
state 514,
it goes to a traffic channel state 515. The traff:~c channel state 515 lasts
as long as
traffic is processed. Wlien. traffic channels stop their action, the terminal
retw-ns to
the initialization state 512.
A communication system should maintaui a call on bidirectional
fundamental channels despite infrequent transmit/receive packets in. the
conventional packet data service. For example, assuming that packet data i.s
transmi.tted/received for one second in about one minute interval, the
communication system should remain logged on the bidirectional fundamental
channels for 59 seconds even with a data transmission/reception suspended. 1n
this
case, a signal transmitted on the bidirectional fmldanientals interferes with.
another
channel, resulting in wasted capacity of another supportable service in the
GDMA
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CA 02242296 1998-10-07
communication network. Furthermore, as more users demand for the packet data
service, the CDMA. mobile communication network becomes less accessible to
users con tined to voice communication on fundamental channels only.
Tl~e constraint of. ColltlrruorrS C0r111eCtloll between. the terminal and th.e
base
station for a short packet transmi.ssion/reception increases packet data
communication cost and places an obstacle on wide provision of the packet data
communication over the CDMA mobile communication network. As a result, the
CDMA mobile communication lags behind other communication systems in
competitiveness and will be less provided.
SUMMARY OF THE INVENTION
An object of the present invention i.s to provide a packet data service
providing method in a CDMA mobile communication. system, for occupying
channels only during packet transrnission/reception while a call is
established.
Another object of the present invention is to a packet data service providing
method, for processing voice and data service channels independently with. a
new
channel structure intl-oduced.
To achieve the above objects, there is provided a packet data service
providing method between a tennilal and a base station in a mobile
commmlication
system. In the nieth.od, packet data is transmitted from the terminal (base
station)
on a reverse (forward) channel to the base station (terminal) during a data
tlvansmission period, and the occupation. of. the reverse (forward) terminal.
is released
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CA 02242296 1998-10-07
during a data transmission suspended period.
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects and advantages of the present invention will become more
apparent by describing in detail a prefen-ed embodiment thereof with reference
to
the attaclred drawings in which:
FIG. 1 is a block diagram of a terminal, a base station, and a radio li.n.k in
a
mobile cornmruii.catiorr system;
FIG. 2 illustrates the structure of areverse channel for a conventional packet
data sewice;
FIG. 3 illustrates th.e structure of. a forward channel for the conventional
packet data service;
FIG. 4 is a .flowchart of using channels for th.e conventional packet data
service;
FIG. 5 illustrates a state transition diagram of a terminal. on the basis of.
a
conventional CDMA standal-d;
FIG. 6 illustrates the structure of a forward channel for a packet data
service
according to an embodiment of the present invention;
FIG. 7 illustrates the structure of a reverse channel for the packet data
service
according to th.e embodiment of the present invention;
FIG. 8 is a state transition diagram of a terminal for the packet data service
according to the embodiment of the present invention;
FIG. 9 illustrates the timing of a packet control channel with respect to that
of a forward packet traffic channel;
FIG. 10 illustrates th.e timing of th.e packet control channel with respect to
CA 02242296 1998-10-07
that of a reverse packet traffic channel; and
FIG. 11 is a block diagram of a base station and a terminal. in a
communication. system for the packet data service according to the embodiment
of
the present invention.
DETAILED DESCRLPT.ION OF THE PREFERRED EMBODIMENT
A. packet data service providing rnetlrod in a CDMA communication. system
according to au embodiment of the present invention avoids occupation of
forward
and reverse channels during a packet data service suspension period with. a
call.
established, to thereby reduce overheads caused by contiguous occupation of
fundatn.ental changers for transm.ission/reception of packet data and afford a
packet
data service to a large number of terminals with one or- a small number of
common
channels.
New channel. structures are designed for the above packet data service, as
shown in FIGS. 6 and 7. A forward channel includes a pilot channel, a sync
channel,
a paging channel, a packet control channel, a .forward packet traffic
charrlrel, and a
forward traffic channel in FIG. 6. The forward traffic charmer is .fw-ther
divided
into a fiu~damental channel anal a supplemental channel. A reverse charnel
includes
an. access charnel, a reverse packet traffic channel, and a reverse traffic
channel in
FIG. 7. The reverse traffic channel is also divided into a fundamental channel
and
a supplemental channel.
Two for-wal-d channels and one reverse channel are newly defined in the
channel. structm'es of FIGs. 6 and 7 for the packet data service according to
the
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CA 02242296 1998-10-07
embodiment of the present invention: the packet control channel and the
forward
packet traff c channel in t1e forward channel; anal the reverse packet traif c
channel.
in the reverse channel.. The forward packet traffic channel supports a path
of. packet
data travelling OI1 a fol-ward link from a base station to a terminal. The
reverse
packet traffic channel supports a path of packet data travelling on a reverse
link
fi-otn. the terminal to tl~e base station.
The packet control channel acts to control tel-minals so that a large number
of terminals accommodate a small number of forward and reverse packet traffic
cl~anlels. It also controls the output power level of a tennin.al accessing;
to a system
on the reverse packet traffic channel, thereby controlling a system capacity,
in turn.
The introduction of the new channels for the packet data service brings a
change to the con.ven.tional state transition diagram of FIG. 5. FIG. 8 is a
state
transition diagram of a terminal for the packet data service according to the
embodiment of. the present invention.
Refewing to FIG. 8, when. power is initially on in a state 81.1, the terminal
is set to an initialization state 81.2. If the tornain.al synchronizes its
timing to that of
a system iti the initialization state 81.2, it transits to an idle state 813.
T.he terminal
may attempt a call, the base station transmits inforniation of the call
attempt to the
terminal on a pagilg channel, and the terminal. sends a page response message
to the
base station on an access channel., ita the idle state 813. Then, the tel-
minal is set to
a system access state 81.4. If the tel-minal fails to obtain. a paging chanlel
message
or is directed from the base station to a different adjacent base station in a
handoff
in the idle state 813, th.e terminal returns to th.e initialization state 812.
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CA 02242296 1998-10-07
If the terminal succeeds in the call attempt or reception of the call
acknowledge signal in the system access state 814, it goes to a traffic
channel state
815. On the contrary, if. the terminal succeeds in system access except for
the call
attempt or reception of a call acknowledge signal in th.e system access state
814, the
terminal retw-ns to the idle state 813. When a packet anode is registered in
the
system access state 81.4, aloe terminal is set to a packet idle state 816.
Meanwhile,
when traffic channels stop their action in the traffic channel state 815, the
terminal
I'et11I71S to initialization state 812.
D11I'Lilg tran.smission/reception of packet data, the tenn.inal .i.s di.rected
from
the packet idle state 816 to a packet busy state 817. Llpon completion of
packet
tran.srni.ssion/reception, the terminal returns to the packet idle state 816.
T.he
tetmin.al alternates between the packet idle state 816 and the packet busy
state 817
depending on packet data transmi.ssion/reception. or vice versa. When the
packet
mode is over in. th.e packet idle state 816, the terminal retLUms to the
initialization
state 812.
The terminal. mainly aiming at a packet data service as shown. in FIG. 8
transits not to the traffic channel state 815 but to the packet idle state
81.6 upon
registration of the packet mode i.n th.e system access state 814.
In th.e packet idle state 816, the terminal peri.odi.cally monitors a packet
control channel to determine whether there is packet data to be received on a
forward packet traffic channel. In the presence of receive packet data, the
terminal
demodulates the forward packet traffic channel during a predetermined time in
the
packet busy state 81.7.
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When there is packet data to be transmitted from the terminal in the packet
idle state 816, it waits for an authorization to use a reverse packet traffic
channel,
while monitoring the packet control channel. Upon receipt of the
authorization, the
te~-~ni.nal transmits the packets on th.e reverse packet traffic channel in
the packet
busy state 817.
Upon completion of tile packet data transmission/reception on the forward
and reverse packet traffic channels in the packet busy state 81.7, the
terminal
periodically monitors the packet control channel agai..n in the packet idle
state 816.
The pm-pose of using th.e packet control channel i.s to reliably provide a
packet data service to a large number of terminals in the packet idle state
via a small
number of forward and reverse packet traffic chancels. The packet control
channel
also controls the output power level of a terminal. on a reverse packet
traffic
channel, thus increasing system capacity.
The packet control channel is constituted as in table l..
Table 1.
forward packet reverse packet reverse packet trafficreserved
traffic channeltraffic channel cliannel power control
bit
status access control (variable BW)
The packet control channel of the above structure remains on, and a single
packet control channel occupies one code channel. A plurality of packet
control
channels can be used for many packet data service subscribers. The single
packet
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contl-ol charmer is accompanied by one or more forward and reverse packet
traffic
channels.
A.s shown in. table l., the packet control channel should notify a terminal.
which. terminal to occupy a forward packet h-af.Iic charnel by broadcasting
the status
of the forward packet traffic channel. It also sh.oul.d broadcast information.
of an
access authority to terminals wlvch intend to occupy areverse packet traffic
channel
so that an. authorized terminal may transm..it packet data on the reverse
traf~.c
channel. The packet control channel transmits a power control bit to control
the
output power levels of tenn.inals in th.e process of trala.smitting packet
data on the
reverse packet traffic channels. Then, the corresponding tenninal.s should
adjust
their own output power levels as directed by the power control bit.
FIG. 9 illustrates the timing of th.e packet control channel with respect to
that
of the forwal-d packet traffic channel, and FIG. 10 illustrates the timing of.
the packet
control. channel with respect to that of the reverse packet traffic chanliel..
Referring to FIG. 9, reference numerals 9a and 9b denote the packet control.
channel and the forward packet traffic channel, respectively. Reference
characters
FPC i and FPT i indicate packet control channel data anal forward packet
traff.c
channel data, assigned to an i-th time slot, respectively.
The terminal is informed of the presence of packet data addressed thereto oli
the packet control channel, while montoring the packet control channel 9a, and
then
demodulates the forward packet traffic channel. 9b. The forward packet traffic
channel status information of. th.e packet control c.l.~an.nel 9a assigned to
an. i-th time
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slot indicates a terminal for which the packet data of an (i+1)-th. tune slot
of. the
forward packet traffic channel 9b. Here, a time slot unit T = T;+, - T,.
Refen-ing to FIG. 1.0, reference characters 10a and lOb denote the packet
conU-ol channel. and the reverse packet traffic channel, respectively.
Reference
character FPCi i.ndi.cates packet control channel data assigned to an i-th
time slot,
for designating a terminal to access an (i+1)-th time slot and controlling the
power
of te1-minals accessing in the i-th time slot. Reference character RPTi
indicates
reverse packet traffic channel data assil;ned to the i-th time slot and having
a
st1-ucture of preamble preceding data. Only terminals authorized to access in
an
(i-1)-th time slot can access the i-th time slot and a terminal authorized but
having
no transmit data i.s denied access. Here, the time slot unit T = T;+, - T,.
FIG. 11 is a block diagram of a base station and a terminal for packet data
communications in a communication system according to an. embodiment of. the
present invention.
In a base station 1100, a packet controller 111.1 outputs col-respondi.ng
signaling signals to a packet control data transceiver 1113 and control
signals to
cowespoliding transceivers 1.115, 1117, and 1119 in order to transmit packet
data
to a terminal 1200 or receive packet data from the terminal 1200. The
signaling
signals output from the packet controller l 1.1l include a forward packet
signal
F SIGP, a reverse packet signal R-SIGP, a forward voice signal F SIGV, a
reverse
voice signal R SIGV, a forward continuous data signal F SIGC, and a reverse
C011t1111to11S data signal R SIGC, anal the control signals include a data
receive
control. signal R CTL and a data transmit control. signal T CTL.
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The packet control data transceiver 1113 transmits the signaling signals
F SIGP, R SIGP, F SIGV, R~SIGV, F SIGC, and R SIGC on a packet control.
signal under the control of the packet controller 11.11. The packet traffic
data
transceiver 1.1 I S tran.smits/receives packet data to/from the terminal 1.200
on packet
traffic channels by control signals T CTL1 and R CTLI. output fi~otn the
packet
controller 111.1. The fundamental. data transceiver 1117 transmits/receives
data
to/from the tet~tninal 1200 on fundamental channels by control signals T CTL2
and
R_CTL2 output from the packet controller 11.11. The supplemental data
transceiver
119 transmits/receives supplemental data to/ti~om the terminal 1200 on
supplemental
channel. by contt~ol signals T CTL3 and R CTL3 output.from th.e packet
controller
111.1.
In the terminal 100, a packet controller 1222 outputs control signals t-ctl
and
t ctl for receivi..ng packet data on. a .forward channel or hvansmi.ttiag data
on a reverse
channel by analysing the signaling signals received from the packet control
data
transceiver 11.1.3 of. the base station. 11.00. The packet controller 1222
also outputs
switch control signals F ON, F OFF, and OFF for selecting a forward or reverse
link. The receive control signal r ctl and the transmit control signal t ctl
are used
to control cowespon.ding transceivers 1224, 1226, arid 1228 for processing
data
translnitted/recei.ved on the .forward/reverse channels. The switch control
signal.
F ON serves to twn on a forward link and tuna off a reverse li.llc, the switch
control
signal F OFF serves to turn off th.e forward link and turn on the reverse
link, and
the control signal OFF serves to turli off. both the forward and reverse
licks.
A. f.rst switch 1234 selects a path for the packet traffic data by th.e switch
control signals F ON 1., F OFF l, and OFF 1. output from the packet controller
1.222.
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The packet traffic data transceiver 1224, connected to the first switch 1234,
transtni.ts or receives packet data on a link selected by the switch 1.234
under the
control of the control signal. t ctl 1 or ~-ctl l output f_i-om the packet
controller 1.222.
A second witch 1236 selects a path for th.e fundamental channel data by the
switch control signals F ON2, F OFF2, and OFF2 output from the packet
controller 1222. The fimdanien.tal data transceiver 1226, connected to the
second
switch .1.236, transmits or receives th.e fundamental channel data on a link
selected
by the second switch .1.236 under the control of the control signal t ctl2 or
r ctl2
output fi-oln the packet cont~~oll.er 1222.
A third switch 1238 selects a path for the supplemental channel data by the
switch control signals F ON3, F OFF3, and OFF3 output from the packet
controller 1.222. The supplemental data transceiver 1.228, connected to the
third
switch 1238, transmits or receives the supplemental channel data on a link
selected
by the third switch 1238 under the control of the control signals t ctl3 or
1_ctl3
output from the packet controller 1222.
Referring to FIG. 11, the base station 1100 and the terminal 129.9 according
to the embodiment of. the present invention employ their respective charmel
structm-es for .independently supporting packet data, as described before.
That is,
the charnel structure of the present invention shown in FIGS. 6 anal 7 newly
define
two forwal-d channels and one reverse channel. Here, the new forward chancels
are
a packet control channel. and a forward packet traffic channel, and the n.ew
reverse
chalmel is a reverse packet traffic channel. The forward packet traffic
channel
supports a path for packet data to be transmitted on a forward channel from a
base
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CA 02242296 1998-10-07
station to a terminal. The reverse packet traffic channel supports a path for
transmitting packet data on a reverse channel. from the terminal. to the base
stati.on..
In addition, the packet control channel allows a large number of. terminals to
share
a small lumber of forward and reverse channels, and controls the output power
levels of. tel-lninals accessing to a system via reverse packet traffic
c.ha.nnels to
thereby control system capacity.
Tl.~e control signals as shown in FIG. L 1 are defned in the following table.
Table 2
F SIGP forward packet signal R CTL data receive control
r ctl signal
R SIGP reverse packet signal T CTL data transmit control
t ctl signal
F SIG forward voice signal F ON forward link ON
V reverse link OFF
R SIG reverse voice signal F OFF forward link OFF
V reverse link ON
F SIGC forwal-d continuous data OFF fol~.vard link
signal OFF
reverse 1W k OFF
R SIG reverse continuous data
signal
C
Intermittent forward packet data communication from the base station 1 1U0
- 16 -
CA 02242296 1998-10-07
to the terminal 1200
The packet controller 1111 sends the control signal F SIGP to the packet
controller 1.222 on the packet control channel by control.l.ing the packet
control data
transceiver 11 13, and outputs the control signal T CTL1 to the packet traffic
data
transceiver 11. l.5 to designate a forward packet traffic channel. Llpon
receipt of. tile
control signal F SIGP from the base station 1100, the packet controller 1222
outputs the control. signal r-ctrl to the packet traffic data transceiver
1224, and the
control signals F ON1, OFF2,OFF3 to the first to third switches 1234 to 1.238,
respectively. In this case, the base station 11.00 sends packet data on tlr.e
designated
forward packet traffic channel and the terminal 1200 processes the packet data
received via the designated forward packet traff.c channel. During
transmission/reception of packet data on the forward link, the base station
1100 and
the terminal 1200 use only the packet traffic channels, not folwar-d
fiu~damen.tal and
supplemental channels. Upon completion of. the packet data
translnission/reception
on tl.~e forward Link,, the packet controller 1222 outputs the control signal
OFF I. to
the first switch 1234 to disconnect the packet data tl-ansmission/reception
path oli
a forward link.
Intermittent reverse packet data communication from the terminal 1200 to the
base station 11.00
The packet controller 11.11 of the base station 11.00 outputs the control
signal
R S1GP to the packet controller 1.222 of the terminal 1200 on the packet
control
channel by periodically controlling the packet control data transceiver 111.3.
In the
presence of packet data to be transmitted to th.e base station 1100, the
packet
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CA 02242296 1998-10-07
controller 1222 of the terminal 1200 designates a packet traffic charnel by
outputting the control signal t ctr l to th.e packet tl-affic data transceiver
1234 and
selects a reverse packet traffic channel by outputting the control signal F-
OFF 1. to
the .fi.rst switch 1234. The packet controller 1.222 of the ternli.nal 1200
turfs off a
link .for a fmidanlental channel and a supplemental charnel by outputting the
control
signals OFF2 and OFF3 to the second and third switches 1236 and 1238,
respectively. Then, the terninal 1.200 transmits packet data on. the reverse
traffic
channel to the base station 1100. On the other hand, in. the absence of packet
data
to be transmitted to the base station 1100, the packet controller 1222 of the
terminal
1200 outputs the control signals OFF1, OFF2, and OFF3 to the first to third
switches 1234, 1.236, and 1238, respectively, to thereby tulm off the link for
the
channels.
Continuous forward data communication from the base station 1.100 to the
terminal 1200
The packet controller 11.11 of the base station 11.00 sends the con t1-ol
signal
F SIGC to the packet controller 1222 of the tel-mi.nal on the packet control
channel
by controlling the packet control data transceiver 1113, and outputs the
control
signals T CTL2 and T CTL3 to the fundamental. data ta-ansceiver 1117 and the
supplemental data transceiver 111.9, respectively, to thereby send data of
fun.dam.ental and supplemental channels. Upon receipt of the control signal.
F SIGC, th.e packet conU-oll.er 1222 of the terninal. 1.200 outputs the
control signals
r ctl2 and r ctl.3 to the fundamental data transceiver 1226 anal the
supplemental data
transceiver 1228, respectively, and outputs the control sigmals F ON2 and F
ON3
to the second and third switches 1236 and 1238, respectively, so that a path
is
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CA 02242296 1998-10-07
desi~n.ated to receive data continuously on the forward fmdamental and
supplemental channels. Then, the base station 1100 continuously tl-a~.~smits
data on
the designated forward fmdalnental and supplemental. channels to the terminal
1200.
Continuous reverse data co~.n:mw.~.ication from the terni.nal 1.200 to th.e
base
station 1100
The packet controller 1111 con tt-ols th.e packet control data hvansceiver
1113
to periodically transmit the control signal R SIGC to the packet controller
1222 of
the terminal 1200 on the packet control charnel, and receives continuous data
front
the terminal. 1200 on reverse fundamelital and supplemental channels by
outputting
the control signals R-CT.L2 and R CTL3 to the fmdaniental data transceiver
1117
and tloe supplemental data transceiver 1117, respectively. In addition, in the
presence of. data to be continuously transmitted to the base station 1100, the
packet
control.l.er 1.222 of the terminal 1200 outputs the control signals t ctl2 and
t ctl3 to
the fmdalnental data transceiver 1226 and the supplemental data transceiver
1.228,
respectively, and th.e control signals OFF1, F OFF2, and F OFF3 to the first
to
third switches 1.234 to 1238. Then, th.e terminal 1200 continuously outputs
data oli
the reverse filndamental and supplemental channels. In the absence of data to
be
continuously transmitted to the base station 11.00, the packet controller
1.222 outputs
the control signals OFF1 to OF.F3 to the .first to third switches 1.234 to
1238,
respectively. Therefore, tile terminal 1200 transmits data continuously oli
the
designated reverse .fundamental and supplemental channels to the base station
1100.
Fol-ward voice colnmuni.cation from the base station 11.00 to the terminal.
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CA 02242296 1998-10-07
1200
The packet controller 11.11. of the base station 11.00 sends the control.
signal
F SIGV to the packet controller 1222 of th.e tetm.inal 1200 by controlling the
packet
control data transceiver 1113 and outputs voice data on the forward
.fmdamental
chan~iel by outputting the control signal T CTL2 to the fundamental data
transceiver 1.117. Upon receipt of the control signal F SIGV on the forward
packet
contt~ol channel, the packet coaltroller 1222 of the terminal 1200 outputs the
control
signals yctl2 to the fundamental data transceiver 1226, and the cont~~ol
signals
OFFI, F ON2, and OFF3 to the first to third switches 1234 to 1238,
respectively.
Thus, the base station 1100 transmits th.e voice data on the forward
fm~.damental
chancel to the terminal 1.200.
Reverse voice communication ii~om the terminal 1200 to the base station
1100
The packet controller 1111 of the base station 1200 sends the conh~ol signal
R-SIGV to the packet controller 1222 of tl.~e terminal 1200 on the packet
control
channel by controlluig th.e packet control data transceiver 1113 and
designates a
reverse i:undamental channel by outputti~.ig the control signal R-CTL2 to the
fmdam.ental data transceiver 1117. Here, in th.e presence of voice data to be
transmitted to th.e base station 1.1.00, the packet controller 1.222 of the
base statio~i
1200 outputs the control sigmal t ctl2 to the fundamental data transceiver
1226 and
designates the reverse fun.damen.tal channel by outputting the control signals
OFF 1,
F OFF2, anal OFF3 to the first to third switches 1234 to 1238, respectively.
Thus,
the terminal 1200 outputs voice data on. th.e reverse fundamental channel to
the base
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CA 02242296 1998-10-07
station 1.200.
As described above, the present invention may maximize channel resource
use efficiency in a packet data service of a mobile communication network by
introducing the packet control channel and the forward anal reverse packet
traffic.
That i.s, the forward or reverse channels are occupied during a packet data
transmissioWreception period after a call set-up, and are unoccupied during a
packet
data transmission/reception. suspended period, thereby enabling efficient use
of
channel capacity.
While the present invention has been described in detail with reference to the
specif c em.bodinient, it is a mere exemplary application. Thus, it is to be
clearly
mderstood that matey variations can be made within the scope and spirit of the
present invention. .en actually impletnenti.ng the packet data service as
described
above, the timing of. the packet control channel with respect to that of the
packet
traffic channel can be different from that as shown. i.n. FIGs. 9 and 10. For
example,
the i-th time slot of. the packet control channel may designate an (i+j)-th
time slot
of the packet traffic channel instead of the (i+l.)-th. time slot.
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