Description
Title of Invelltioti
COMMUNICATION TERMINAL, COMMUNICATION METHOD, BASE
STATION AND COMMUNICATION SYSTEM
Technical Field
[OOOI]
The present disclosure relates to a cotntnunication terminal, a
10 coln~nunicationm ethod, a base station and a cotnmunication system.
Background Art
[0002]
Ctlrrently, standardization of LTE radio comt~n~nicatiosny stems is under
15 progress by 3GPP (Tliird Generation Partnership Project). According to LTE,
inlprovement in masimutn communication speed and quality i~nprovetnent in cell
edges call be attained by using technologies st~clla s relays and carrier aggregation.
Moreover, considerations are giver1 to improving coverage by introducing base
stations other than eNodeB (macro-cell base station), such as MeNodeB (Home
20 eNodeB), a ferntocell base station, a cornpact base station for cell phones, and RHH
(Remote Radio Head).
[0003]
Moreover, disctrssion on MTC (Macliine T)lpe Comtnunicatiol~s) is also in
progress in the 3GPP. The MTC is generally synonymous to M2M (Machine to
25 Machine) and refers to a comtntlnication between niachines and not directly used by
a hornan. The MTC pritnarily is perfortiled between a server and an MTC terminal
that is not directly used by a human and is colisidered as a noticeable elemetlt
technology for efficiently coupling dispersing devices, for example, in a sensor
network.
30 [0004]
When the LTE is applied to the above-mentioned MTC, a battery for MTC
terminals is desirable as less frequently to be replaced as possible because the battery
replaceluent highly costs manpower and MTC terminals can possibly be installed in
places having difficalty of the battery replacecnent.
[OO05]
5 Incidentally, it is thought that average power consu~nption of a ternlinal can
be reduced by extending a paging cycle longer in LTE idle mode than in connection
mode. In addition, Patent Literature 1 and Patent Literature 2 disclose improvement
of the paging scheme.
10 Citation List
Patent Literature
[O006]
Patent Literature I : JP 2010-288278A
Patent Literature 2: JP 2010-050969.4
Summary of Invention
Technical Problem
[OO07]
Nevertheless, since the paging cycle defined in LTE is 2.56 s (256 system
20 frames) at the longest, the power consulnption is difficult to be sufficiently reduced.
[OOOS]
Therefore, the present disclosure proposes a communication terminal, a
cotnn~unicationm ethod, a base station and a communication system which are novel
and inlproved and by which a processing interval for paging can be made longer.
25
Solution to Problem
[0009]
According to the present disclosure, there is provided a communication
ter~ni~lianlc luding a tinling detection unit that detects arrival of timing according to a
30 configured cycle, a condition determination unit that determines whether or not a
shared condition shared with a base station is satisfied, and a c o n ~ ~ ~ ~ u ~ l i c a t i o ~ ~
controller that controls receptio~lo f paging when the timing detection unit detects the
arrival of timing and the condition deter~ninatiotl unit deterniines that the shared
cotlditiotl is satisfied.
[OO 1 01
5 According to the present disclosure, there is provided a communication
method including detecting arrival of timing according to a co~ifigured cycle,
determining whether or not a shared condition shared with a base station is satisfied,
and controlling reception of paging when the arrival of titning is detected and it is
determined that the shared condition is satisfied.
10 [OOII]
According to the presetit disclosure, there is provided a base station
including a timing detection unit that detects arrival of timing according to a
configured cycle, a co~lditiotl deter~nination unit that determines whether or not a
shared condition shared \\
Currently, standardization of LTE radio cotll~llutlicatio~sly stems is in
5 progress in 3GPP. The embodiments according to the present invention can be
adapted to an LTE radio communication systelll as above by way of exatnple and,
first, at1 overview of the LTE radio communication system \\(ill be described.
[0020]
(1-1. Configuration of Radio Co~nm~~nicatSioysnt em)
10 FIG. 1 is an explanatory drawing of an exemplary configi~rationo f a radio
communication system. As illustrated in FIG. 1, the radio co~nmutlication systeni
includes a base station 10, a core network including an MME (Mobility Management
Entity) 12, an S-GW (Serving Gatexvay) 14 and a P-GW 16 (Packet Data Nettvork
Gatewa)(), UEs (User Equipments) 20 and an external server 30.
15 [0021]
The embodiment according to the present invention can be adapted to radio
communication devices such as the base station 10 and the UEs 20 illustrated in FIG.
I . Notably, the base station 10 may be, for example, an eNodeB, a relay node or a
Honle eNodeB which is a compact base station for home use. Moreover, the UEs
20 20 may be either tlon-MTC terminals such as a mobile phone and a PC (Personal
Computer) or MTC terminals specialized for MTC which refers to a cot~~munication
between tnachit~esa nd not directly used by a human discussed in the 3GPP.
roo221
The base station 10 is a radio base station configured to co~nmonicatew ith
25 the UEs 20. FIG. I illustrates only one base station 10, whereas a number of base
stations 10 are co~~nectetod t he core network in reality.
[0023]
The MME 12 is a device co~lfiguredt o perfonn controls of settings, opening
and hand-over of a data commutlication session. The MME 12 is connected to the
30 base station 10 via an interface called S1.
[0024]
The S-GW 14 is a device configored to perfom1 routing, transfer and the
like of user data. The P-GW 16 futlctiotis as a connecting node with an IP service
~ietworka nd transfers the user data to and frotn the IP service network.
[0025]
5 The UE 20 is a coln~liutlication tertninal configured to perform radio
com~nonicatio~wii th the base station 10. The UE 20 perfornis radio communication
with the base station 10 according to an application. Moreovet; the UE 20 performs
bidirectional communication with the external server 30 via the core network.
Notably, the external server 30 tnay be either a server device installed by an LTE
10 carrier or a server device of an Internet infom~ation service carrier externally
connecting to the LTE network.
[0026]
The UE 20 operating as an MTC ternlitla1 by way of example generally has
the follo\\.ing features, whereas not every MTC ter~ninal 20 needs to have all of the
15 following features but which of the features is to be assigned depends on an
application.
-Scarce needs to move (Lo\\, Mobility)
-Transmission of s~iialdl ata (Online S~nalDi ata Transmission)
-Very lo\\, po\Irer consumption (Extra Low Power Consumption)
20 -Handled by grouping respective MTCs (Group-based MTC Features)
[0027]
(1-2. Frarne Configuration)
The above-mentioned base station 10 and UEs 20 perform com~iiutiication
according to a COI~II~IOIfIr ame format. Hereafter, a specific example of the frame
25 forniat is described with reference to FIG. 2.
[0028]
FIG. 2 is an explanatory d~a\ving illostrating an LTE fratne format. As
illustrated in FIG. 2, a 10-ms radio frame is collfigitred of ten 1-tns sub-frames #O to
#9. A number identifier called systetn frame number (SFN) is assigned to each of
30 10-111s radio frames and the systetii fra~ne nutnber increases from 0 to 1023.
Moreovet; each of the 1-tns sub-frames is configured of two 0.5-111s slots.
Futthenuore, each of the 0.5-ms slots is configured of seven Ofdrn sytnbols.
[0029]
Notably, the Ofdtil sylnbol is a unit used it1 a cotnlnutlication schetne of an
OFDM (Orthogonal Frequency Division Multiplexing) tnodulation system and is a
5 uliit by which data processed in one time of FFT (Fast Fourier Transform) is
outputted.
[0030]
Moreover, at the head of each I-ms sub-frame ilti~stratedi n FIG. 2, a control
signal called PDCCH (Physical Domnlink Control Channel) is added. One Ofdm
10 sytnbol to three Ofdm sytnbols at the head of the st~b-framea re used for trat~sinission
of the PDCCH. Namely, there is a case where one Ofdln syinbol is used for
transmission of the PDCCH or there is also a case where three Ofdl11 sylnbols are
used for the same.
[003 I]
15 Notably, a region in the radio frame used for transmission of the PDCCH is
called a colltrol region and a region in the radio frame used fol tratis~nissiolls of a
PDSCH (Physical Downlink Shared Channel) or a PUSCI-I (Physical Uplink Shared
Channel) is called a data region.
[0032]
20 (1-3. Paging)
The elnboditnent relates to communication between the above-mentioned
base station 10 atid UEs 20 and specifically relates to paging h ~thne ba se station 10
to the UEs 20. Therefore, the paging in LTE will be described, followed by specific
description of the embodiment.
25 [0033]
The base station transmits a paging message for calling each UE to each UE
that is in idle mode in paging timing according to a constant period such as a
discontinuous reception period called DRX (Discontinuous Reseption) cycle for each
UE. Namely, the base station transmits the paging message in a paging cycle
30 corresponding to the DRX cycle for each UE. As above, a calling procedure for
calling a UE by nleans of transmission of a paging message is the paging.
Meanwhile, the UE in idle mode confirms whether or not a paging tnessage is
transmitted in pagitig timing according to the DRX cycle and performs power saving
by turning off power supply for primary circnits for reducing battery power
consumption to as less an extent as possible in a period except the paging timing.
5 [0034]
FIG. 3 is an explanatory drawing illostrating a concept of paging. As
illustrated in FIG. 3, the UE confinns whether or not a paging message is transmitted
in paging timing 82, 84 and 86 according to the DRX cycle. Since a paging
tnessage is not transmitted in paging timing 82 and 84, the UE does not receive a
10 paging message herein.
[0035]
On the other hand, the base station transmits a paging tnessage (RRC paging
message) in paging timing 86 according to tlie DRX cycle immediately after
reception of an SlAP paging tilessage from the MME (S92 and S94). Therefore,
15 the UE can receive tlie paging tnessage in the paging timing 86.
[0036]
More in detail, the UE monitors whether or not there is infor~natioti
indicating the presence of a paging message in the PDCCM in the paging timing,
using a fised value (FFFE) as a P-RNTI (Radio Network Temporary Identify) for
20 paging. Then, when the fised value (FFFE) is detected as the P-RNTI in the paging
timing, the UE decodes the paging message succeedinglp transmitted in the PDSCH.
The paging message includes a ter~ninal ID (S-TMSI: SAE Temporary Mobile
Subscriber Identifier) of the target UE, cletwork domain information (circoitlpacket),
S1 change itifor~iiation, ETWS infonnation, and the like. When the UE recognizes
25 that tlie pagitig message is to itself, it starts connection to the base station in a
random access manner,
[0037]
(1 -4. DRX cycle)
As above, tlie overview of the paging has been described. Succeedingly,
30 the above-mentioned DRX cycle and paging timing are described more specifically.
Notably, tlie 10-ms radio fraine is hereinafter referred to as system frame.
[0038]
The DRX cycle includes a cell inherent DRX cycle (discontinuous reception
cycle colnlnou in a cell) which is assigned to and common to all the UEs in the cell
and user inherent DRX cycles (discontinuous reception cycle for a terminal) which
5 are individually assigned to the UEs.
[0039]
The cell itlherent DRX cycle takes any value of 4 system frame numbers of
32, 64, 128 and 256 and is reported as 2-hits information with system infonnation
SIB2. Notably, siuce 1 system frame length is 10 nls, 32 system frames, 64 system
10 frames, 128 systetn frati~esa nd 256 systetn frames correspond to 320 Ins, 640 ms,
1.28 s and 2.56 s, respectively.
[0040]
Similarly, the user i~il~erenDtR X cycle is 2-bits infonnation indicating any
of 4 system frame numbers of 32, 64, 128 and 256. The user inherent DRX cycle is
15 reported froin the MME to the base station and the UE with tile SlAP paging
message. Otherwise, the user inherent DRX cycle is reported to the network side in
connection request from the UE or mith an update message of a tracking area.
[0041]
(1-5. Paging Timing) - -
20 The paging timing is determined according to the above-described DRX
cycle. For example, 3GPP TS36.304 describes the following for~iiulae for
determining the LTE paging timing.
[0042]
[Math. I]
T
SFN mod T = - [UE - ID mod N}
N
(formula 1)
[0043]
[Math. 21
is = ~loor[U-E I D I N} mod N,
(formola 2)
[0044]
[Math. 31
(fonnula 3)
[0045]
[Math. 41
(forn~ula4 )
I0 [0046]
[Math. 51
(formula 5)
[0047]
15 In the above-mentioned formulae, SFN denotes a system fia~ne nc~mber
taking any value of 0 to 1023, T denotes a DRX cycle, UE-ID denotes lo~ver 10 bits
of IMIS stored in a UE's USIM card, and nB denotes a palameter reported from the
network and takes any value of 4T, 2T, T, Tl2, Tl4, TI8, TI16 and Tl32.
[0048]
20 Formola I mentioned above indicates an algoritlnii for determining the
system frame n~~tnbteor u ndergo the paging in LTE. The base station performs tlie
paging with this SFN in accordance with formula 1 above when the remainder
obtained by dividing the SFN by the DRX cycle T is equal to the value obtained by
the right side. Notably, as indicated by for~iiula 3, the smaller one of the cell
25 inherent DRX cycle (Tc) atid the user inherent DRX cycle (TuE) is used as a DRX
cycle T. When tlie user inherent DRX cycle Tuc is not assigned, the cell inherent
DRX cycle Tc is used as the DRX cycle T.
[0049]
Herein, since the right side of for~iiula1 includes an operation using IMIS of
the UE, the paging timing for each UE is random timing with a uniform distribution.
Notably, fonnula 2 indicates an algorithm for determining the sub-frame for which
the paging is performed in the system frame determined according to formula 1.
5 Similarly in fonnula 2, since it includes an operation using lMIS, the sub-frame for
which the paging is performed is also randomized.
[0050]
(1-6. Background of Emboditnent)
By the way, when LTE is applied to the above-mentioned MTC, a battety
10 for MTC terminals is desirable as less frequently to be replaced as possible because
the battery replacement highly costs manpower and MTC terminals can possibly be
installed in places having difficulty of the battery replacement. Although it is
tliought that a DRX cycle in idle mode is made longel; it is difficult for a DRX cycle
with a longer period exceeding a cycle of system frames (1024 system kames) to be
15 attained. Hereafter, the reason is described. .
[0051]
As mentioned above, the DIlX cycle in idle mode is 32, 64, 128 or 256
system frames. Therefore, the DRX cyclc is 2.56 s at the longest. The algorithm
for determining the paging timing described in reference to formula 1 restricts the
20 DRX cycle to be less than 1024 systeln frames (10.24 s) which correspond to the
cycle of system frames even if any alternatives for a longer DRX cycle. However,
it is,assumed that the DRX cycle is desired to be a longer cycle for fo~thcoming
MTC. For example, it is thot~ght that the DRX cycle is desired to be a cycle of 30
seconds, I minute or longer for applications giving a first priority to the service life
25 of batteries.
LO0521
As to this point, it is thought that the DKX cycle to be a longer cycle is
attained by making the cycle of systeln frames longer than 1024 system frames.
Howeve]; this measure is not the best solution, taking compatibility with the existing
30 ter~iiinalsi nto consideration, because this affects the whole system.
[0053]
Moreover, sj'stem parameters designating the DRX cycle employ tlie cell
inherent DRX cycle Tc and the user inherent DRX cycle TUE as mentioned above.
However, as indicated by formula 3, the algorithm for deterrnitiing the paging timing
eniploys the smaller one of the cell inherent DRX cycle and the user inherent DRX
5 cycle TUE as the DRX cycle Tc. Accordingly, the DRX cycle is difficult to be
attained to be a longer cycle even if the user inherent DRX cycle TUE is made longer
than the cell inherent DRX cycle Tc.
[0054]
On the other hand,the DRX cycle can be made longer if both of the cell
10 inherent DRX cycle Tc and the user inherent DRX cycle TUE are niade longer.
Ho\\rever, this affects the DRX cycles of all the UEs in the cell. For example, since
notification of an ETWS (Earthqclake/Tsuna~nWi arning System) is to be included in
a paging message, tlie ETWS does not operate properly if both of the cell inliesent
DRX cycle Tc and the user inherent DRX cycle TUE are niade longer.
15 [0055]
Moreovet; according to the algorithm for deterinining tlie paging timing
described with reference to fonnala 1, since tlie paging tinling for each UE is random
timing with a in~iform distribution, concentration of radio resources used for paging
can be prevented. This is thought to be preferable when tlie DRX cycle is 2.56 s at ~ ~
20 the longest. However, if the DRX cycle is niade longer, tlie paging timing suffers a
distribution within tlie longer cycle. As a result, there is a risk that the paging is
performed-in timing exceedingly apart from intended timing. ~ .., ,
[0056]
Frotii another viewpoint, the user inherent DRX cycle T Uis~ re potted from
25 tlie UE in any tinling in connection request at initiation of the UE (attachiog request)
and in updating a tracking area (tracking area updating). However, there is a case
where the UE operating as an MTC tenninal has lo\\, mobility. Moreover, report of
the user inherent DRX cycle Tut is not a process which is supposed to be performed
in arbitrary timing. Hence, it is supposed that the user inherent DRX cycle TUc is
30 reported to the network in low frequency.
[0057]
Therefore, the enlbodi~nent has been devised directed by the above-
~nentioned circumstances. According to the etnbodiment, a processing interval for
paging can be made longer individt~ally for every UE to exceed the cycle of system
frames. Iiereafter, an overall flow, a configuration of the base station 10, a
5 configuration of the UE 20 and the like according to such an enlbodiment will be
sequentially described in detail.
[OOSS]
<2. Overall Flow of Radio Communication System>
FIG. 4 is an explanato~y drawing illustrating an overall flow of the radio - .
10 commt~nications ystem according to the embodiment. As illustrated in FIG. 4, first,
the external server 30 tmnsmits paging instruction information to the UE 20 via the
P-GW 16, the S-GW 14 and the base station 10 while the UE 20 is operating in
connection mode (S310, S312, S314 and S316).
[0059]
15 The paging instruction infonnation includes information regarding a
determination method of the paging timing. For example, the paging instruction
information includes the user inherent DRX cycle TUE, flag inforlnation indicating
whether or not a determination method of the paging timing according to the
embodiment is perfomled, an extension parameter K and infonnation regarding re-
20 paging used in a case of failure of the paging. Note that part or all of the abovementioned
information regarding a determination method of the paging timing may
be stored in a storage mediunl soch:as a SIM card of the UE20. In this case, the , . ~ -.
paging instructioil inforn~atiori may include information instructing usage of the
information stored in the storage medium of the UE 20 for deternlining the paging
25 titning.
[0060]
h40reovel; the above-mentioned flag information rnay be FGI (Featore
Group Indicator) information. The FGI infor~nation is generally used as a bit
information string by ~vhich the UE 20 indicates affirmative or negative of tising a
30 specific fi~nction of the UE 20 to the network. The extension parameter K is a
parameter for making a processing interval for paging longer as described from <3.
Configuration of Base Station> in detail. Notably, the above-mentioned reporting
of the paging instructioti infortnation tnay be performed separately into a plarality of
times.
[0061]
5 Succeedingly, the UE 20 reports the paging instructioti infortilation received
from the external server 30 to the base statioti 10 and tlie MME 12 (S320 and S322).
Thereby, the paging i~istructiotl infortilation can be shared with the UE 20 and the
network side including the base station 10 and the MME 12. Notably, when the
infonilation regarding a deteniiitiation method of the paging tiinitig is stored in the
10 storage medium of the UE 20, the UE 20 may cotnpare tlie paging instruction
informatioti received from the external server 30 with the information stored in the
storage tlieditlm properly to update the information stored in the storage medium.
[0062]
Then, after the UE 20 moves to idle mode, the paging is performed in a
15 longer cycle than the cycle of system fiatnes using the paging instruction infortl~ation
shared in connection mode (S330, S332, S334, S336 atid S338).
[0063]
<3. Configuration ofBase Station>
As above, tlie overall flowof the radio communicatiot~s ystem according to
20 the embodiment has been described. Succeedingly, a configuration of tlie base
station 10 according to the etnbodiroent is described with reference to FIG. 5.
. ~ [0064] ,~ . . ~ ~ .~ ~ , . .... . .. ~ ~ .-
FIG. 5 is a filnctio~ialb lock diagra~iil lustrating a configuration of the base
station 10 according to the embodilnent. As illastrated in FIG. 5, an antentia 116, an
25 antenna sliaring device 118, a receiver circuit 120, a transtnitter circuit 122, a
received data processing unit 132, an ititerface 133, a tra~istiiission data processitig
unit 138, an tipper layer 140, a controller 150 and a storage I60 are included.
[0065]
The antenna 116 receives a radio signal froin the UE 20 atid converts the
30 radio signal into an electric received signal. Since the antenna 116 is con~ieoted to
tlie receiver circuit 120 via the antenna sharing device 118 in receiving signals, the
received signal obtained by the antenna 116 is supplied to the receiver circuit 120.
100661
Moreover, since the antenna 116 is connected to the transmitter circuit 122
via tlie antenna sharing device 118 in transmitting signals, a trans~nissio~sig nal is
5 supplied to the antenna 116 from the transmitter circuit 122. The antenna 116
transmits the trans~nissions ignal to the UE 20 as a radio signal.
[0067]
Notably, only one antenna is illustrated in FIG. 5 for convenience of
explanation, whereas the base station 10 tnay include a plurality of antennas. When
10 including a plurality of antennas, the base station 10 can perform MiMO (Multiple
Input Multiple Outpot) communication, diversity co~n~nunicatioan d the like.
[0068]
The receiver circuit 120 perfornis demodulation processing, decoding
processing and the like on the received signal supplied from the antenna 116 and
15 supplies the.received data after the processing to the received data processing unit
132. As above, the receiver circuit 120 fi~nctionsa s a receiving unit in cooperation
with the antenna 116.
100691
The transmitter circuit 122 performs tnodulation processing and the like on
20 a control signal supplied fro111 the controller 150 (PDCCH. BCH and tile Like) and a
data signal supplied fro111 tlie transmission data processing unit 138 (PDSCH) and
supplies the trans~nissio~silg tial after the pmcessing to the antenna 11 6. As above,
transmitter circuit 122 fi~nctiotis as a transmitting unit in cooperation with the
antenna 116.
25 [0070]
The received data processing icnit 132 analyzes the received data supplied
from the receiver circuit 120. Then, the received data that is for the upper layer 140
is supplied to the interface 133. On the other hand, the paging instruction
information that is received from the UE 20 is supplied to the controller 150 to be
30 stored in the storage 160.
[0071]
The interface 133 is an interface to and from the upper layer 140. The
received data is outputted fro111 the interface 133 to the upper layer 140 and the
transmission data is inputted fsom the upper layer 140 to the interface 133.
[0072]
5 The transmission data processing anit 138 generates a data signal on the
basis of the data supplied from the interface 133 to supply it to the transmitter circuit
122.
[0073]
The controller 150 includes a co~ntnunicatiotc~o ~ltroller 152, a timing
10 detection unit 154, a counter 156 and a condition determination unit 158. The
storage 160 stores the paging instruction infortnation. The colltroller 150 co~ltrols
the whole operations of the base station 10 using the paging instruction infor~nation
stored in the storage 160.
[0074]
15 (Timing Detection Unit)
The tinling detection unit 154 detects paging candidate timing which arrives
according to the user inherent DRX cycle TuE included in the paging instruction
infor~nationr,e gartling the target UE 20. For example, the timing detection unit 154
{nay detect the paging candidate timing according to formula 6 below.
20 [0075]
[Math. 61
1 SFN mod T,, = ~ { U- IED m od NJ
N
(formula 6)
[0076]
25 When the remainder obtained by dividing the SFN by the user inherent
DRX cycle TUE is equal to the value obtained in the right side, the timing detection
unit 154 detects the relevant SFN as the paging candidate timing according to
fonnula 6 above. Notably, fortnula 6 by way of example indicates that the SFN is
divided by the user i~lherentD RX cycle TUEw, hereas the detection method of the
paging timing is not limited to the above example. For example, the timing
detection unit 154 may use the cell inherent DRX cycle Tc in place of the user
inherent DRX cycle Tue or may use the s~nallero ne of the cell inherent DRX cycle
Tc and the user inherent DRX cycle TuE as indicated by formula 3.
5 [0077]
(Counter)
The counter 156 counts elapse of a predeter~nined period. For example,
the counter 156 stalls counting fiom "0", increments a count value i every time the
user inherent DRX cycle Tw elapses, and resets the count value i to "0" when the
10 count value i reaches the extetension parameter K incloded in tlie paging instructiotl
infortnation. Notably, the explanation is made for usage of the user inherent DRX
cycle TUE by \\lay of example as the predetennitled period above, whereas the
predetermined period tnay be the cell inherent DRX cycle Tc or may be a period in
relation to neither the user inherent DRX cycle TUE nor tlle cell inherent DRX cycle
.15 Tc.
[0078]
(Condition Determination Unit)
The condition determination unit 158 detertnines whether or not a shared
condition shared with the UE 20 regarding the paging issatisfied. For example, the
20 condition determination unit 158 detennitles that the shared condition is satisfied
when the count value i obtained by the counter 156 is equal to a setting value x
. .... . ., . shared \\9itl~th e UE 20. Herein, the setting value :x by way of example is
represented as in fortnt~la7 below. Notably, the setting value x is not limited to the
value indicated by formola 7. For example, tlie setting value x tnay be a value
25 directly designated from the external server 30.
[0079]
[Math. 71
x=UE - IDmodK
[OOSO]
(Comn~unicationC ontroller)
The co~n~nunicatioco~ni troller 152 co~itrolst ransmission of the paging to
the UE 20 when the tinling detection unit 154 detects the paging candidate ti~iii~ig
and tlie conditio~dl etermination unit 158 determines that the count value obtained by
the counter 156 is eqi~atlo the setting value x. According to such a configuration,
tlie period of the paging tiniing can be extended, for example, to the multiplication
value of the inherent DRX cycle TUE and the extension parameter K. Hereafter, this
is described more specifically with reference to FIG. 6.
[OOS I ]
FIG. 6 is an explatlatory drawiilg illustrating a specific example of the
paging timing according to the embodiment. Notably, FIG. 6 by way of example
illustrates that tlie user inherent DRX cycle TUE is 128 (system frames), the extension
parameter K is 47 and the setting value x is 1.
[0082]
When the user inherelit DRX cycle T Uis~ 1 28, the paging carididate timing
arrives at all interval of 128 system frames, as illustrated in FIG. 6, at the SFNs being
"I", " 129" a~id "257". Notably, although the paging calldidate tiliiing corresponds
to the rioniial paging tiniing, tlie paging is not always perfor~iied at all tlie pieces of
paging candidate tillling it1 tlie embodiment.
[0083]
. Namely, the communicatio~c~o ~itroller1 52 perfor~iist he paging when the
count value i obtained by the counter 156 is equal to the setting value x in tlie paging
candidate timing. For example, as illustrated in FIG. 6, the count value i is "0" for
the SFN being "1" which is in the paging candidate timing, but is different fiom tlie
setting value s being "I". Therefore, the co~n~iit~nicatcioon~trio ller 152 does not
perforti? tlie paging. Meanwhile, since the coont value i is "I" for the SFN being
"129" which is in the paging candidate timing, and is equal to the setting value x
being " 1 ", the communication controller 152 perfoniis tlie paging. Afterwards, the
conlmunicatio~i controller 152 does not perform tlie paging until the count value i
reaches "46" and is reset to "0" to become " 1" again, and performs tlie paging in the
paging candidate titning when the count value i becomes "1".
[0084]
Namely, when the user inherent DRX cycle TL,i~s 128 (system frames) and
the extension parameter K is 47, the interval of the paging timing can be extended to
5 6016 syste~iif rames (approximately 1 iiiinute) which is the ~nultiplicationv alue of
Tm and K.
[0085]
As described above, the base station 10 according to the embodiment can
~ ~~ make the intervalof the paging~timing longer. as a resalt, power consamption in . . -- -
10 the UE 20 can be reduced.
[0086]
Notably, the communication controller 152 may determine paging timing
for sub-fianies according to for~liitla 2 or may determine it according to a method
separately instructed fiom the external server 30. Moreover, when the paging to the
15 UE 20 has resulted in failure? the paging [nay be performed again based on
infonnation regarding re-paging \vhich is included in the paging instruction
infonnation.
[0087]
14; Configuration of UE> ~. . . ..
20 As above, the configuration of the base station 10 according to the
embodiment has been described. Succeedingly, a configuration of the UE 20
according to the embodi~nenits described with reference to FIG.7. - . . .. .. , : . , . . . .. .. .
[0088]
FIG. 7 is a fi~nctional block diagram illustrating a cotifiguration of the UE
25 20 according to the embodiment. As illustrated in FIG. 7, the UE 20 according to
the embodimeut includes an antenna 216, an antenna sharing device 218, a receiver
circuit 220, a transmitter circuit 222, a received data processing unit 232, an interface
233, a transmission data processing unit 238, an upper layer 240, a controller 250 and
a storage 260.
30 [0089]
The antenna 216 receives a radio signal fioni the base station 10 and . ~
converts the radio signal into an electric received signal. Since the antenna 216 is
connected to the receiver circuit 220 via the antenna sharing device 21 8 in receiving
signals, the received signal obtained by the antenna 216 is supplied to the receiver
circuit 220.
5 [0090]
Moreover, since the antenna 216 is connected to the transmitter circuit 222
via tlie antenna sharing device 218 in transmitting signals, a transmission signal is
st~pplied to the antenna 216 &o~n the transmitter circuit 222. The antenna 216
transmits the transmission signal to the base station 10 as a radio signal.
10 [0091]
Notably, only one antenna is illustrated in FIG. 7 for convenience of
explanation, whereas tlie UE 20 may include a plurality of antennas. When
including a plurality of antennas, the UE 20 can perforni MIMO communication,
diversity conimunication and tlie like.
15 [0092]
The receiver circt~it 220 perfor~ils demodulation processing, decoding
processing and tlie like on the received signal supplied fiom tlie antenna 216 and
sc~ppliest he received data after the processing to tlie received data processing unit
232. As above, the receiver circuit 220 filnctions as a receiving tt~iitin cooperatioli
20 with the antenna 216.
[0093]
The transmitter circuit 222 performs modulation processing and the like on
a control signal supplied froni the controller 250, a data sigtial supplied from tlie
transtnissio~i data processing unit 238 and tlie like and supplied the transtilission
25 signal after tlie processing to tlie antenna 216. As above, the transmitter circuit 222
fi~nctionsa s a transmitting unit in cooperation with the antenna 2 16.
[0094]
The received data processing unit 232 analyzes the received data supplied
fiom the receiver circuit 220. Then, the received data that is for the upper layer is
30 supplied to the interface 233. On the other hand, tlie paging instruction infomiation
that is received from the external server 30 is supplied to tlie controller 250 to be
stored in the storage 260.
[0095]
The interface 233 is an interface to and fro111 the upper layer 240. The
received data is outputted from the interface 233 to the upper layer 240 and the
5 trans~llissiond ata is inputted from the upper layer 240 to tlie interface 233.
[0096]
The upper layer 240 is a functional unit for executing an application
according to the UE 20. Notably, examples of the application include "Metering",
"Health" and the like. When the application is "Metering", the transmission data is
10 supposed as data indicating consumption amounts of water supply and electricity.
Moreovef; when the application is "Health", the transmission data is supposed as data
indicating current physical status of the subject.
[0097]
The transn~issioil data processing t~nit 238 generates a data signal on the
15 basis of the data slipplied fiom the interface 133 to supply it to the transmitter circuit
222.
[0098]
The cotitroller 250 includes a co~niiiunication controller 252, a timing
detection unit 254, a counter 256 and a condition determination unit 258. The
20 storage 260 stores the paging instruction information. The controller 250 controls
the \vliole operation of the base station 10 using the paging instructio~l infornlation
stored in tlie storage 260.
[0099]
(Tinling Detection Unit)
25 The timing detection unit 254 detects paging candidate tinling nrhich arrives
according to the tiser inherent DRX cycle T,IE included in the paging instruction
infosolation. For esaniple, according to fonnula 6 nlentioned above, when the
remainder obtained by dividing the SFN by the user inherent DRX cycle TUE is equal
to the value obtained in the right side, the timing detection unit 254 detects the
30 relevant SFN as the paging candidate timing.
[O 1001
(Counter)
The counter 256 counts elapse of a predetermined period. For example,
the counter 256 starts counting fro111 "0", increments a count value i evety time the
user inherent DRX cycle TUE elapses, and resets the count value i to "0" when the
5 count value i reaches the extension parameter K included in the paging instruction
information. Notably, the explanation is made for usage of the user inherent DRX
cycle Tw by way of exatnple as the predeterlnined period above, whereas the
predetermined period may be the cell inherent DRX cycle Tc or may be a period no
relation to the user inherent DRX cycle TUE or cell inherent DRX cycle Tc. .
10 [OlOl]
(Condition Determination Unit)
The condition determination utlit 258 detertnines whether or not the shared
condition shared with the base station 10 regarding the paging is satisfied. For
exa~nplet,h e cotldition tleter~ninationu nit 258 determines that the shared condition is
15 satisfied when the cou~itv alue i obtained by the counter 256 is equal to the setting
value x shared with the base station 10. I-Ierein, the setting value x by way of
example is represented as in fomlula 7 n~entioned above.
[O 1021
(Communication Controller) -
20 The commu~~icatiocno atroller 252 cotltrols reception of the paging when
the titniclg detection t111i2t 54 detects the paging candidate timing and the condition
determination unit 258 determines that the count value obtained by the counter 256 is
equal to the setting value s. According to such a configuration, the period of the
paging timing can be extended, for example, to the lnultiplicatio~v~a lue of the
25 inherent DRX cycle TVE and the extension paratneter K. As a result, power
consumption in the UE 20 can be reduced. Notably, since the ficnctions of the
communication controller 252 are largely conllnon to the f~~nctionos f the
communication controller 152 of the base station 10, their description is herein
omitted.
30 [0103]
15. Operations of Base Station and UE>
As above, the base station LO and the UE 20 according to the ernbodinie~lt
have been described. Succeedingly, operations of the base station 10 and the UE 20
according to the e~nbodi~neanrte organized with reference to FIG. 8 and FIG. 9.
[0 1041
(Operation of UE 20)
FIG. 8 is a flowchart illustrating operation of the UE 20 according to the
embodiment. As illusttated io FIG. 8, the UE 20 transmits the paging instruction
information received from the external server 30 to the base station 10 in connection
tnode(S404). Afterward, when the UE 20 niove to idle mode (S408), the counter
10 256 initializes the count value i (S412). Notably, information regarding
initialization timing for the count value i may be included in the paging instruction
information or processing of adjusting the initialization timing wit11 the base station
10 liiay be separately performed.
[0105]
15 Succeedingly, the condition determination unit 258 recognizes the count
value i of the counter 256 (S416) and determines ~vhethero r not the count value i is
equal to the setting value s indicated in forniula 7 (S420). When the count value i
is equal to the setting values, the process proceeds to S424 and when the count value
i is different fiom the setting value s, tlie process proceeds to S428.
20 [0106]
Then, when it is deter~nined that tlie count value i is equal to the setting
value s, the cotnmtinication controller-252 perfonus receiving processing of the
paging at a predetermined sub-franie of the SFN that is detected by the timing
detection unit 254 and satisfies formula 6 (S424).
25 [0107]
Afterward, wllen the user inlierent DRX cycle TUE lias elapsed after the
initialization of the count value i or the previous update thereof (S428) and the count
value i is not "K-I" (S432), the counter 256 increments the count value i. On the
other hand, \vlien the user inherent DRX cycle TUE has elapsed after the initialization
30 of the count value i or the previous update thereof (S428) and tlie count value i is "K-
1" (S432), tlie counter 256 initializes the count value i to "0" (S440). Then, after
the processing in S436 or S440, the processing in and after S416 is repeated.
[0108]
(Operation of Base Station)
FIG:9 is a flowvcha~t illostrating operation of the base station 10 according
to the embodiment. As illustrated in FIG. 9, the base station 10 receives tlie paging
instruction information from the UE 20 while the UE 20 is in connection mode
(S504). Afterward, when the UE 20 move to idle mode (S508), the counter 156
initializes tlie count vallre i (S512). Notably, information regarding initialization
timing for thecount-value inlay be included in the paging~instructionin formation or
processing of adjusting the initialization tinting with the UE 20 may be separately
performed.
[0 1 091
Succeedingly, the conditio~i determination unit 158 recognizes the coant
value i obtained by the colrtiter 156 (S5 16) and deterniines \\.hether or not tlie count
value i is equal to the setting value s indicated in forrilula 7 (S520). When the
cot111t value i is equal to tlie setting value s, the process proceeds to S524 and whet1
the count valoe i is different from the setting value x, tlie process proceeds to S528.
[OIIO]
'Then, \\?hen it is detem~ined that the count valuei equal to tlie setting value
s, the coininunication controller 152 perfonns receiving processi~igo f the paging at a
predetermined sub-frame of the SFN that is detected by the timing detection unit 154
and satisfies fotnlula 6 .. . . . . . ...~ .
(S524).
[Olll]
Afterward, \\,lien the user inherent DRX cycle TUE lias elapsed after the
initialization of the count valoe i 01. the previous opdate thereof (S528) and the count
value i is not "K-1" (S532), the counter 156 increnlents the count value i. On the
other hand, when tlie user inherent DRX cycle Tue has elapsed after the initialization
of the count value i or the previous update thereof (S528) and tlie count value i is "K-
1" (S532), the counter 156 initializes the count value i to "0" ($540). Then, after
the processing i'i S536 or S540, tlie processing in and after S516 is repeated.
[0112]
<6. Conclusioti>
As described above, accorditig to the embodiments, an interval of paging
timing can be made longer while colilpatibility with existing terminals is maintained.
As a result, power consumption in the UE 20 can be reduced.
[0113]
The preferred enibodilnents of the present disclosure have been described
above in detail with reference to the accompanying drawings, but the technical scope
of~thep resent disclosl~reis not limitedto the above examples. A person skilled~in
the art niay find various alterations and tiiodifications within the scope of the
appended claiills, and it should be understood that they will naturally collie under the
techtiical scope of the present disclosure.
[0114]
For example, eacli step of processing in the base statioti 10 atid tlie UE 20
herein does not necessarily need to be perfomled cl~ronologically in the order
described as a sequence diagram or a flowchart. For example, eacli step of
processing in tlie base station 10 and the UE 20 may be performed in an order
different from the order described as a flowchart or in parallel.
[0115] - . . ~. ...
Also, a cotnputer program caosing hardware soch as a CPU, ROM, RAM
atid the like contained in the base statioti 10 or the UE 20 to futiction on a par mitli
each configuration of the basestation 10 or the UE 20 described above. . ,~n.addition,
a storage medium in which the computer progratn is stored is provided.
[0116]
Additionally, the present technology may also be configured as below.
(1)
A communication ter~ilinali ticluding:
a timing detection unit that detects arrival ofiitnitig according to a
cotitigured cycle;
a condition detel.minatiot1 unit that determines whether or not a shared
cotidition shared \\,it11 a base station is satisfied; and
a co~ntnunication controller that cot~trots reception of paging when the
timing detection unit detects tlie arrival of timing and the condition determination
unit determines that the shared condition is satisfied.
(2)
The co~nmunicationte rminal according to (I), fi~rtheri ~lcluding
a counter that counts elapse of a predetermined period,
wherein the condition determination unit determines that the shared
condition is satisfied when a count value obtained by the counter is eclual to a setting
value shared with the base station. ~ . ~ ~ ~
10 (3)
The co~nmonicationt erminal according to (2),
wherein the predetermined period is the configured cycle.
(4)
The com~nunicationte rlninal according to (2) or (3),
15 wherein the counter initializes the count value when the count value reaches .
the setting val~te.
(5)
The cotnmonicatioti tenuinal according to any one of (2) to (4),
. - wherein the setting value is reported from an external server to the
20 comn~uoicationte rminal via tlie base station.
(6)
The communication terminal according to any one of (1) to (5)$ '
wherein the configored cycle is a discontinuot~s reception cycle for a
terminal, tlie cycle being assigned i~ldividt~altloy the communication terminal: or a
25 discontinoous reception cycle colnlnotl in a cell, the cycle being assigned in cotnlnoti
to communication tertninals in a cell of the base statio~i.
(7)
A commt~nicationm ethod including:
detecting arrival of timing according to a configured cycle;
30 determining whether or not a shared condition shared with a base station is
satisfied; and ~ ~
controlling reception of paging when the arrival of timing is detected and it
is determined that the shared condition is satisfied.
(8)
A base station inclading:
5 a timing detection unit that detects arrival of timing according to a
configured cycle;
a condition detertnination uoit that determines wl~etlier or not a shared
condition shared with a communication ter~ninails satisfied; and
a communication controller that controls transmission of paging to the
10 communication terminal when the timing detection litlit detects the arrival of timing
and the condition determination unit determines that the shared condition is satisfied.
(9)
A communication method including:
detecting arrival of timing according to a configured c)rcle;
15 determining whether or not a shared condition shared with a communication
terminal is satisfied; and
controlling transmission of paging to the communication terminal when the
arrival of timing is detected and it is determined that the shared condition is satisfied.
(10)
20 A comtiiunication system including:
a base station including
a first timing detection unit that detects arrival of timing according
to a configured cycle,
a first condition determination uoit that detertilines \vhetIier or not a
25 shared condition is satisfied, and
a first communication cantroller that controls transmission of
paging when the first timing detection unit detects the arrival of timing and the first
condition determination onit determines that the shared condition is satisfied; and
a communication terminal including
a second timing detection unit that detects the arrival of timing
according to the configured cycle,
a second condition detenninatioti unit that determines whether or
not the shared cotldition shared with the base station is satisfied, and
a second commanication controller that cotltrols reception of
pagiiig when the second timing detection unit detects tlie arrival of timing and the
5 second cotlditiotl determination utiit deteriilines that tlie shared condition is satisfied.
Reference Signs List
base station
MME
S-GW
P-GW
UE
external server
controller
cotnmunication controller
ti~nitigd etection unit
counter
condition detemiination unit
storage
controller
communication controller - .
timing detection unit
counter
condition determination unit
storage
CLAIMS
Claim 1
A comtnunication terminal comprising:
a timing detection unit that detects arrival of tinting according to a
5 configured cycle;
a condition determination unit that determines whether or not a shared
conditiolt shared with a base station is satisfied; and
a communication controller that controls reception of paging when the
titning detection unit detects the arrival of timing and the cortdition detennination
10 unit detenuines that the shared cottdition is satisfied.
Clainl 2
The communication ter~ninaal ccording to clai~n1 , further co~nprisi~tg
a counter that counts elapse of a predetermined period,
15 wherein the. condition determination unit deter~lii~tetsh at the shared
condition is satisfied ~vhena count value obtained by the counter is eqoal to a setting
value shared with the base station.
- Claim 3 . .
20 Tlte communicatio~t erminal according to claim 2,
ivherein the predetermined period is the configured cycle.
~. ~.- . ~.. ~... , . ~~ . . , .. . - , . . ~. . .~ d.
Clai~t4l
The commc~~iicatiotenr minal according to claitll2,
25 wherein the counter initializes the cou~tvt alue when the count value reaches
the setting value.
Claim 5
The communication terminal according to clai~n2 ,
wherein the setting value is reported from an exter~tal server to the
cottlmunication terminal via the base station.
Claim 6
The communication tenninal accorditlg to claitli 1,
wherein the configured cycle is a discontinuous reception cycle for a
5 terminal, the cyccl being assigned individually to the coinmunication terminal, or a
discontinuous reception cycle cotnlnon in a cell, the cycle being assigned in colnlnon
to communication tertilitials in a cell of the base station.
Claiti~7 -
10 A communicatiotl tnethod comprising:
detecting arrival of timing according to a configured cycle;
determining whether or not a shared condition shared with a base statiotl is
satisfied; and
cotltrolling reception of paging wlie~tih e arrival of titnitig is detected and it
I5 is determined that the shared condition is satisfied.
Clailii 8
A base station co~iiprising:
a timing detection itnit that detects arrival of timing according to a
20 configored cycle;
a condition detennination unit that detennines whether or not a shared
condition sliared with a cotnmunication terminal is satisfied; and
a cotiltiit~nication cotitroller that controls transniission of paging to the
cotnmunication tertnitial when the titnitig detection unit detects the arrival of timing
25 atid the condition detern~inationu tiit determines that the shared condition is satisfied.
Claim 9
A conimunication method comprising:
detecting arrival of timing accorditlg to a configured cycle;
determining whether or not a shared condition shared with a comoiunication
terminal is satisfied; atid
controlling transmission of paging to the coinmunication terminal when the
arrival of timing is detected and it is determined that the shared condition is satisfied.
Claim 10
A communication system comprising:
a base station including
a first timing detectioti unit that detects arrival of timing according
to a configured cycle,
~. .~ .... . . . . a first-condition deter~ninatioxu~n it that deter~nitlesw hether or not a - .. ~
10 shared condition is satisfied, and
a first communication controller that lcontrols transmission of
... .. ~, paging when the first timing detection unit detects the arrival of timing and the first
condition detennination unit deter~ninesth at the shared condition is satisfied; and
a communicaGon termitla1 including
15 a second timing detection unit that detects the arrival of timing
according to the configured cycle,
a secoiid condition determination unit that determines whether or
not the shared condition shared with the base station is satisfied, and . .
.a- second communication controller that controls reception of .
20 paging when the second timing detection unit detects the arrival of timing and tlie
. - second condition detei.~ninationu nit determines thatthe shqred condition is satisfied.