Telecommunications – Radiotelephone system – Zoned or cellular telephone system
Reexamination Certificate
2000-06-23
2004-12-21
Chin, Vivian (Department: 2682)
Telecommunications
Radiotelephone system
Zoned or cellular telephone system
C455S432200, C455S438000, C455S439000, C455S442000, C455S450000, C370S329000, C370S331000, C370S460000
Reexamination Certificate
active
06834190
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to state transition in a mobile communication system, and in particular, to a method of controlling the change of a radio physical channel caused by transition between an active mode and a control hold mode in a traffic channel substate of a mobile station or a base station in the base station.
2. Description of the Related Art
A conventional CDMA (Code Division Multiple Access) mobile communication system provides primarily voice service. From this CDMA mobile communication system, IMT (International Mobile Telecommunication)-2000 standards have been evolved. An IMT-2000 mobile communication system is capable of additionally providing a high quality voice service, a moving picture service, Internet browsing, and various other data communications.
The standard CDMA mobile communication system is comprised of a base station (BS) having a base station transceiver system (BTS) and a base station controller (BSC), a mobile switching center (MSC), and a mobile station (MS). Radio links between the MS and the BTS are a forward link on which data is directed from the BTS to the MS and a reverse link on which data is directed from the MS to the BTS.
All channels are grouped into physical channels and logical channels. A logical channel is established on a physical channel. It is possible to establish a plurality of logical channels on one physical channel. If the physical channel is released, the logical channels are also released. A physical channel is not necessarily established prior to establishment of a logical channel. When an intended physical channel is set up for another logical channel, all that should be done is to allocate a logical channel in question on the established physical channel.
The physical channels are divided into dedicated channels and common channels according to their natures. The dedicated channels are dedicated to communications between a BTS and an MS, including a fundamental channel (FCH), a dedicated control channel (DCCH), and a supplemental channel (SCH). The FCH is commonly used to transmit data according to the for TIA/EIA-95-B standard and transmits a voice signal, a data signal, and a signaling signal (or a control signal). The DCCH transmits a data signal and a signaling signal. The SCH transmits a large amount of data. All other physical channels except the dedicated channels are common channels. The common channels are shared commonly by a plurality of MSs to communicate with a BTS. A physical channel on a forward link is a paging channel and a physical channel on a reverse link is an access channel. These common channels are compatible with the IS-95-B standard.
Dedicated logical channels allocated on the physical channels are a dedicated signaling channel (DSCH) and a dedicated traffic channel (DTCH). The DSCH can be allocated on an FCH and a DCCH. On the DTCH can be allocated all of the FCH, DCCH, and SCH information. The DSCH is so called because it transmits a control signal between a BTS and an MS. The DTCH is used to transmit user data between the BTS and the MS. Common logical channels allocated on the common physical channels are a common signaling channel (CSCH) for transmitting a signaling signal and a common traffic channel (CTCH) for transmitting user data. The common logical channels are allocated on the paging channel for the forward link and on the access channel for the reverse link.
In the CDMA mobile communication system, packet data communication is characterized in that transmission of burst data alternates with long non-transmission periods. Connection of a channel only at a data transmission starting point has been suggested for a packet data communication service in the future mobile communication system. That is, in consideration of limited radio resources, base station capacity and power consumption of an MS, a BS should secure a channel for data communication with another MS by releasing the channel for a non-data transmission period and rapidly reconnecting the channel when data transmission resumes. In addition, the BS should provide the MS with a function of controlling channel allocation duration, channel allocation action time, and channel allocation end time.
FIG. 1
is a diagram of transition between an active mode and a control hold mode in a traffic channel substate where traffic channel frames are communicated between an MS and a BS.
Referring to
FIG. 1
, an ERM (Extended Release Message), an ERMM (Extended Release Mini Message), and a UHDM (Universal Handoff Direction Message) are used for transition from the active mode to the control hold mode. An RAM (Resource Allocation Message), an RAMM (Resource Allocation Mini Message), an ESCAM (Extended Supplemental Channel Allocation Message), a Forward/Reverse SCAM (Supplemental Channel Allocation Message), and a UHDM are used for transition from the control hold mode to the active mode. An SCH can be allocated between the MS and the BS and gated transmission is not implemented on a reverse pilot channel in the active mode. On the other hand, the SCH is not allocated between the MS and the BS and the reverse pilot channel is gated-transmitted in the control hold state.
FIG. 2
illustrates a reference model as provided by the 3G IOS (Interoperability Specifications) for a digital air interface between an MSC and a BS and between BSs in a general mobile communication system.
Referring to
FIG. 2
, an A
1
interface and an A
2
/A
5
(exclusive for circuit data) are defined for transmitting a signal and user information respectively between an MSC
20
and a BSC
32
. An A
3
interface is defined to connect a target BS
40
to a frame selection/distribution function unit (SDU)
34
of a source BS
30
for soft/softer handoff between the BSs
30
and
40
. Through the A
3
interface are transmitted signaling and user data between the target BS
40
and the SDU
34
of the source BS
30
. An A
7
interface is defined to transmit/receive signals between the target BS
40
and the source BS
30
for soft/softer handoff between the BSs
30
and
40
. An A
8
/A
9
interface is used for transmitting signaling and user data between the source BS
30
and a PCF (Packet Control Function) block
50
. A
10
and A
11
interfaces are defined to transmit signaling and user data between the PCF
50
and a PDSN (Packet data Serving Node)
60
.
Wired communications links between BSs and between a BS
30
and an MSC in the CDMA mobile communication system are forward link directed from the MSC to the BS, a reverse link directed from the BS to the MSC, and link connected between the BSs. Specific procedures are performed in BSs and MSCs when packet data is transmitted within a BS, between the BSs, and between the MSCs.
FIG. 3
illustrates function mapping for state transition between modes shown in FIG.
1
.
In
FIG. 3
, the function mapping is shown for the case that MAC and L2/L3 are given to a source BSC
32
, an MS
2
is within the coverage area of the target BTS
40
after soft handoff, and the MS
2
or the BSs are transited from an active mode to a control hold mode or vice versa. Here, the source BS
30
is responsible for controlling a radio channel in use for the MS
2
. Therefore, a signal for controlling the radio channel is transmitted through an A
7
or A
3
signal message. For example, when the active mode is transited to the control hold mode, an SCH used for communication between the MS
2
and a channel element
46
of the target BTS
40
should be released and the source BSC
32
should inform the target BTS
40
of information about gated transmission of a reverse pilot channel. On the other hand, upon transition from the control hold mode to the active mode, gated transmission of the reverse pilot channel is discontinued and an SCH is allocated to the MS
2
when necessary.
IMT-2000 standards are under development. However, this standardization work does not include definition of either a signal message (on the A
7
interface) for mode transition between a BSC and an MS
Lee Hyun-Seok
Yong Chang
Chin Vivian
Dilworth & Barrese LLP
Samsung Electronics Co,. Ltd
Yun Eugene
LandOfFree
Controlling method and apparatus for transition between... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Controlling method and apparatus for transition between..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Controlling method and apparatus for transition between... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3321160