Note: Descriptions are shown in the official language in which they were submitted.
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Description
Method and device for data processing in a communication net-
work
The invention relates to a method and to a device for data
processing in a communication network. Also, a communication
system is suggested comprising at least one such device.
A radio network typically comprises a base station (BS, also
called base transceiver station, NodeB, eNodeB or eNB), a mo-
bile device (also referred to as user equipment (UE), mobile
station or mobile terminal) and optional network elements
that provide interconnections with a core network. The BS
connects the UE via a so-called radio interface (also re-
ferred to as air-interface).
3GPP TS 36.321, V9.3.0, section 5.7 "Discontinuous Reception
(DRX)" describes a means for minimizing the UE's battery con-
sumption and for maximizing the UE's battery lifetime. This
applies to UEs which are in a so-called RRC CONNECTED mode.
The DRX functionality can be summarized as follows (see also
3GPP TS 36.321, section 5.7):
(a) If DRX is disabled, a UE continuously monitors a physi-
cal downlink control channel (PDCCH) for uplink (UL) and
downlink (DL) grants.
(b) If DRX is enabled, the following applies:
¨ The timeline is divided into DRX cycles, each com-
prising the same number of subframes (according to
3GPP TS 36.211, a subframe is 1/10 of a radio frame
and the length of a subframe amounts to 1ms), wherein
one DRX cycle follows the next. The start of a DRX
cycle is linked to a system frame number (SFN) and a
UE-specific offset.
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¨ There are certain periods of time within a DRX cycle
when the UE is in a "DRX Active" mode. If the UE is
in the "DRX Active" mode, it monitors the PDCCH for
UL and DL grants (UL grant and DL grant correspond to
indications sent on the PDCCH in order to grant a DL
or a UL transmission). Hence, the UE can receive DL
transmissions and can convey UL transmissions.
¨ When the UE is in a "DRX Sleep" mode (i.e. in case it
is not in the "DRX Active" mode), the UE does not
monitor the PDCCH for UL and DL grants. Hence, the UE
is not able to receive DL transmissions on a PDSCH
for dedicated transport channels and will not perform
UL transmissions on a PUSCH. Being in "DRX Sleep"
mode, the UE's receiver that handles the reception on
the PDCCH and a physical downlink shared channel
(PDSCH) is switched off and the UE thus saves power.
DRX cycles can have the following lengths: 10ms, 20ms, 32ms,
40ms, 64ms, 80ms, 128ms, 160ms, 256ms, 320ms, 512ms, 640ms,
1024ms, 1280ms, 2048ms or 2560ms. A "DRX OnDuration" timer
and a "DRX Inactivity" timer are defined by 3GPP as follows:
(a) DRX OnDuration timer:
¨ One such timer is provided per UE.
¨ The timer is started with the first subframe of a DRX
cycle.
¨ If the timer is running, the UE is in the "DRX Ac-
tive" mode.
¨ Possible settings for this timer are defined in 3GPP
TS 36.331.
¨ Unit: number of PDCCH subframes.
(b) DRX Inactivity timer:
¨ One such timer is provided per UE.
¨ The timer is started or restarted if the PDCCH indi-
cates a new UL or DL transmission and if the UE is in
"DRX Active" mode at that time.
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PCT/EP2010/060808
- If the timer is running, the UE is in the "DRX Ac-
tive" mode.
- Possible settings for this timer are defined in 3GPP
IS 36.331.
- Unit: number of PDCCH subframes.
Fig.1 shows a schematic diagram visualizing the functionality
of a DRX OnDuration timer and a DRX Inactivity timer in a ra-
dio network between an eNB 103 and a UE 104.
At the beginning of every DRX cycle 101, the DRX OnDuration
timer 102 is started. Hence, the UE 104 is in "DRX Active"
mode for the first subframes of the DRX cycle 101 and can re-
ceive DL and UL grants from the eNB 103. At a time 105, a DL
grant is sent on the PDCCH from the eNB 103 to the UE 104 and
the DRX Inactivity timer is started (indicated by an arrow
107) thereby extending the duration of the "DRX Active" mode.
At a time 106, another DL grant is sent to the UE 104 and the
DRX Inactivity timer is re-started (indicated by an arrow
108), which extends the "DRX Active" mode for this UE 104.
Restarting of the DRX Inactivity timer results in the DRX In-
activity timer window being moved (extended) with every grant
indicating a new transmission in UL or DL. This only occurs
in case the UE 104 is the "DRX Active" mode; otherwise, the
UE 104 cannot receive such grant from the eNB 103. If the eNB
103 continuously provides such grants to the UE 103, the DRX
Inactivity timer window is moved beyond the end of the DRX
cycle 101, into the next DRX cycle 101. In such exemplary
scenario, the UE 103 does not enter the "DRX Sleep" mode dur-
ing such DRX cycle 101.
If the eNB 103 does not provide any grants towards the UE
104, the DRX Inactivity timer expires and the UE 104 stops
being in the "DRX Active" mode, hence it enters the "DRX
Sleep" mode and is no longer able to listen on the PDCCH. In
this scenario, the UE 104 is not able to receive and process
any further DL grants from the eNB 103 until it awakes again,
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e.g., at the beginning of the next DRX cycle when the DRX On-
Duration timer will be re-started or - as an alternative -
when the UE 104 sends out a "Scheduling Request" at any time
within the DRX cycle in order to indicate towards the eNB 103
that data in the UE's buffer requires UL transmission.
Fig.2 shows a schematic diagram visualizing the functionality
of a "Scheduling Request" 201 issued at a time tl within a
DRX cycle 204 by a UE 203 towards an eNB 202.
During the DRX cycle 204 the UE 203 enters the "DRX Sleep"
mode. Hence, within this DRX cycle 204 the UE 203 will not
receive any information from the eNB 202 unless the UE 203
itself initiates communication with the eNB 202 via the
"Scheduling Request" 201.
The "Scheduling Request" 201 can be sent at any time during
the DRX cycle 204 when corresponding resources on PUCCH are
assigned to the UE. These resources are assigned at a given
periodicity (amounting to, e.g., 40ms) for one subframe. The
UE 203 sends the "Scheduling Request" 201 when there is UL
data to be conveyed to the eNB 202. Sending the "Scheduling
Request" 201, the UE 203 becomes active. Pursuant to the
"Scheduling Request" 201, the UE 203 remains in the "DRX Ac-
tive" mode until the eNB 202 conveys an UL grant and the UE
203 starts the DRX Inactivity timer 205.
At a time t2, the eNB 202 starts the DRX Inactivity timer 205
and conveys an UL grant on the PDCCH to the UE 203. The UE
203 remains in the "DRX Active" mode due to the pending
"Scheduling Request" 201 and the running DRX Inactivity timer
205. At a time t3, the UE 203 transmits the UL data on the
PUSCH towards the eNB. As the DRX Inactivity timer 205 has
not yet expired, the UE 203 remains in the "DRX Active" mode.
If several UEs are scheduled without taking into account
their relative time with respect to "DRX Active" mode and
"DRX Sleep" mode, the eNB may not be able to get the data
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conveyed within a DRX cycle. Fig . 3 shows a timing diagram
visualizing this problem. For example, the eNB may have first
DL data to be conveyed to a first UE 301 and second DL data
to be conveyed to a second UE 302. At a time 303, the first
UE 301 is near entering its "DRX Sleep" mode and the second
UE 302 is still for some more time in its "DRX Active" mode.
If the eNB decides to first convey the second data to the
second UE 302 it will not be able to convey the first data to
the first UE 301 within the same DRX cycle, because at a time
304 the first UE 301 will have entered "DRX Sleep" mode and
cannot be reached by the eNB within this DRX cycle. This
leads to a considerable delay 305 of data transmission to-
wards the first UE 301.
This kind of uncontrolled scheduling with respect to the du-
ration of "DRX Active" modes may lead to poor delay perform-
ance of a UE, which enters the "DRX Sleep" mode, e.g., in a
subsequent subframe. This is in particular a crucial issue
considering settings for DRX, which lead to long periods for
the UE maintaining its "DRX Sleep" mode. For example, VoIP
connections require good performance and minor delay, because
the voice transmitted is susceptible to any such delay. On
the other hand, the UE has to economize its resources, thus
using the DRX functionality to save energy.
The problem to be solved is to overcome the disadvantages
mentioned above and in particular to provide an efficient so-
lution utilizing the DRX functionality.
This problem is solved according to the features of the inde-
pendent claims. Further embodiments result from the depending
claims.
In order to overcome this problem, a method is provided for
data processing in a communication network,
¨ wherein a terminal is assigned a scheduling priority
based on a time period until the terminal enters a
sleep mode.
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This approach provides the advantage that the likelihood of
considering a particular terminal increases when this termi-
nal reaches the end of its active mode (before entering the
sleep mode). Hence, by considering the remaining time periods
of (mobile) terminals being in their active mode, a delay in
data transmission can be significantly reduced.
It is noted that the concept suggested herein is applicable
for mobile networks as well as for fixed networks and for
combinations thereof.
The approach described allows assigning a scheduling priority
based on a time period unit the mobile or fixed terminal en-
ters the sleep mode. This corresponds to the fact that the
terminal has to be scheduled during its active mode. It is
noted that the active mode may be a portion of an energy-
saving (e.g., DRX) cycle during which the terminal could be
reached by the network component, in particular the base sta-
tion.
It is further noted that a terminal (in particular a UE) may
run several services in parallel. Hence, providing a schedul-
ing priority could be service-specific, i.e., it may be ap-
plicable for a subset of services.
With regard to LTE services, a differentiation in handling
required is achieved by providing a mapping to separate bear-
ers; hence, a bearer may correspond to a basic means for an
eNB to utilize service differentiation. Therefore, the pri-
oritization mechanism suggested could be applied for at least
one bearer, in particular a subset of bearers, i.e., based on
an availability of data of a certain bearer to be transmitted
to/from the UE.
In an embodiment, the terminal is a mobile terminal or a
fixed terminal.
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The mobile terminal may be any mobile device or mobile sta-
tion with an interface to a wireless network, in particular
to a mobile telecommunication network. Hence, the communica-
tion network may be a telecommunication network comprising a
radio portion (e.g., a radio access network) and a wireline
portion. In such a scenario, the duration of the "DRX Active"
mode and/or the "DRX sleep" mode may be correlated over both
parts of the networks and the prioritization may be aligned
with regard to the end-to-end connections.
Also, the terminal can be a terminal of a fixed network.
In another embodiment, the terminal provides an energy-saving
functionality.
The energy-saving functionality may comprise said sleep mode
and the active mode of the terminal.
In a further embodiment, the energy-saving functionality com-
prises a discontinuous reception functionality comprising in
particular a "DRX Active" mode and a "DRX Sleep" mode.
Hence, the time until the terminal enters the "DRX Sleep"
mode (or the time the terminal stays in the "DRX Active"
mode) can be considered when assigning a scheduling priority.
The closer the end of the phase of the "DRX Active" mode ap-
proaches, the more likely the particular terminal will be
considered for scheduling purposes by, e.g., a base station.
It is noted that the terminal may use a discontinuous trans-
mission functionality to save energy. In such scenario, the
power amplifier or parts of the transmission chain could be
powered down during the time when the system is in the "DRX
Sleep" mode. Then, no uplink data may await transmission from
the UE.
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In a next embodiment, scheduling priority is assigned by a
component of the communication network, in particular by a
base station of a radio access network.
Hence, the base station (e.g. eNB) may consider the mobile
terminals (UEs) attached via said scheduling mechanism. The
prioritization allows utilizing the active modes of the mo-
bile terminal such that data is transmitted to the mobile
terminals before a timer at the mobile terminal expires and
the mobile terminal enters its sleep mode. It is noted that
the sleep mode may in particular last a predetermined period
of time (e.g., a DRX cycle) then the mobile terminal may re-
enter its active mode.
It is also noted that the mobile terminal may actively get
re-activated during its sleep mode in case it needs to convey
data to the base station (a scheduling request is sent to the
base station by the mobile terminal and the mobile terminal
is thus again in its active mode). On the other hand, there
may be no possibility for the base station (for the rest of a
DRX cycle) to re-activate the mobile terminal after it has
entered the sleep mode.
It is also an embodiment that the terminal is assigned a
scheduling priority, said priority is increased with the de-
creasing time left until the terminal enters the sleep mode.
It is noted that the priority may depend on or it may change
with the remaining active time.
Pursuant to another embodiment, the scheduling priority com-
prises a weighting factor that is based on a time left until
the terminal enters the sleep mode.
In particular, the scheduling priority may be based on a type
of the terminal, a service being used (utilizing, e.g., a
service-specific weight), a remaining delay target, a re-
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source utilization (time, frequency, power, codes, etc.) and
any combination thereof.
It is noted that the weighting factor depending on a remain-
ing active time can be applied to any combination of criteria
for prioritization purposes. For example, several weighting
factors may be provided depending on several criteria, in
particular at least on one prioritization scheduling crite-
rion.
According to an embodiment, the scheduling priority is based
on at least one class or type of terminal and/or service.
For example, delay-sensitive traffic can be scheduled using a
higher weighting factor (and thus resulting in a higher like-
lihood of traffic being conveyed) compared to best effort
traffic. This allows considering delay-sensitive terminals
(e.g., mobile terminals conveying VoIP) with a higher prob-
ability in particular in case these terminals approach the
end of their active modes.
According to another embodiment, scheduling among several
terminals is prioritized based on the time the terminals en-
ter the sleep mode.
In other words, with regard to the DRX functionality, the
scheduling (e.g., by a base station) can be conducted pursu-
ant to the time left for each mobile terminal (e.g., UE) in
its respective "DRX Active" mode. A weighting factor can be
utilized dependent on the remaining time in "DRX Active"
mode.
In yet another embodiment, scheduling among several terminals
is prioritized based on quality of service information and/or
channel quality information.
Hence, the scheduling may in particular consider (in addition
to the time left in active mode for each terminal) further
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criteria, e.g., a QoS (e.g., based on a service level agree-
ment) and/or a (e.g., measured) channel quality. For example,
a terminal utilizing a service that requires a high QoS can
be prioritized higher than a service that is, e.g., less sus-
ceptible to delay. Also, the channel quality may be consid-
ered such that a poor channel may trigger an increase or a
decrease of the prioritization for a particular terminal.
Timers related to DRX can be defined in the specification for
the UE side, i.e., the UE may (re-)start a DRX OnDuration
timer or a DRX Inactivity timer based on certain trigger con-
ditions (e.g., the DRX Inactivity timer is (re-)started as
soon as the UE has been scheduled). The eNB may thus predict
or track the status of the UE's DRX mode based on the same
configuration information (i.e., timer settings, etc.) and
monitor trigger events for (re-)starting timers (e.g., sched-
uling of the UE, reception of a scheduling request, etc.).
According to a next embodiment, the terminal conveys a timing
information regarding its sleep mode and/or an active mode to
the network component assigning the scheduling priority.
Hence, the timing information regarding sleep and/or active
mode can be conveyed from the (mobile) terminal to the net-
work component, e.g., the base station (eNB). The terminal
thus informs the network component about its intention to en-
ter the sleep mode and/or about the time when it is going or
intends to enter the sleep mode.
Pursuant to yet an embodiment, the terminal conveys a request
to enter sleep mode to the network component assigning the
scheduling priority.
The (mobile) terminal may ask the network component whether
or not it is acceptable to enter its sleep mode. Hence, the
network component may indicate to the mobile terminal that it
shall not yet enter the sleep mode, because additional data
is to be conveyed from the network component to the terminal.
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Also, the terminal may obtain a confirmation from the network
component to enter the sleep mode. As an alternative, a timer
could be used by the terminal in order to wait for a response
from the network component for a predefined period of time;
if no such response has been provided when the timer expires,
the terminal enters the sleep mode.
It is noted that the UE may determine the "DRX Active" mode
and the "DRX Sleep" mode based on configuration information
(e.g., timer settings, etc) and/or trigger conditions, and
the eNB may predict the UE's "DRX Active" mode and/or the
UE's "DRX Sleep" mode based on the same (type of) informa-
tion.
The problem stated above is also solved by a device for data
processing in a communication network, comprising or being
associated with a processing unit that is arranged
¨ for assigning a scheduling priority to a terminal
based on a time period until the terminal enters a
sleep mode.
It is noted that the steps of the method stated herein may be
executable on this processing unit as well.
It is further noted that said processing unit can comprise at
least one, in particular several means that are arranged to
execute the steps of the method described herein. The means
may be logically or physically separated; in particular sev-
eral logically separate means could be combined in at least
one physical unit.
Said processing unit may comprise at least one of the follow-
ing: a processor, a microcontroller, a hard-wired circuit, an
ASIC, an FPGA, a logic device.
As an embodiment, the device could be a component of the com-
munication network, in particular a base station of a radio
access network.
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The solution provided herein further comprises a computer
program product directly loadable into a memory of a digital
computer, comprising software code portions for performing
the steps of the method as described herein.
In addition, the problem stated above is solved by a com-
puter-readable medium, e.g., storage of any kind, having com-
puter-executable instructions adapted to cause a computer
system to perform the method as described herein.
Furthermore, the problem stated above is solved by a communi-
cation system comprising at least one device as described
herein.
Embodiments of the invention are shown and illustrated in the
following figures:
Fig.4 shows an exemplary diagram visualizing possible
weighting factors in view of a time duration until a
mobile terminal enters its "DRX Sleep" mode;
Fig.5 shows a network component, e.g., a base station, a
gateway, a router, a switch, etc. that is connected
to a network and the network component is connected
to two terminals, wherein the terminals are scheduled
by the network component.
The solution presented herein in particular suggests priori-
tizing UE scheduling such that a UE, which is closer to an
end of its "DRX Active" mode, will be scheduled with a higher
probability.
The solution allows for a dynamic prioritization among sev-
eral UEs as follows:
(1) UEs that are in "DRX Active" mode that will last at
least as long as a predetermined duration (given, e.g.,
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by a threshold value) can be scheduled according to a
criterion (e.g., pursuant to a normal schedule) for QoS
and/or channel quality. This enables QoS differentiation
and channel-aware scheduling gains.
(2) UEs that are close to an end of their "DRX Active" mode
(e.g., time remaining in "DRX Active" for the UE is be-
low a given threshold value) can be scheduled, e.g.,
with an increased priority. For example, the priority
can be increased with the decreasing time left in the
"DRX Active" mode.
Hence, a prioritization of UEs can be provided pursuant to
their individual time left in the "DRX Active" mode. A
weighting factor can be utilized dependent on the remaining
time in "DRX Active" mode; such weighting factor takes into
account the distance to the end of the current "DRX Active"
mode phase. The closer the end of the "DRX Active" mode, the
higher the weighting factor may be set so that the respective
UE is scheduled by a base station (eNB) with a higher prob-
ability at the end of its current "DRX Active" mode.
The criterion for scheduling of UEs may in particular depend
on QoS information and/or channel quality. For example, a
criterion Cl(t) for prioritization of a UE i for scheduling
with respect to an upcoming subframe t can be set as follows:
Cl(t) = f ( QoS, channel quality(t),
Hence, the criterion Cl(t) can be a function dependent on the
QoS, the channel quality over time t, etc. This criterion
Cl(t) can be adjusted for the UEs running in "DRX Active"
mode by a weighting factor w as follows:
Ci,DRX_Activity (t) = (t) * W (t diSti)
with t dist, being a time duration from an actual time t to
an end time of the UE's i current "DRX Active" mode. This new
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criterion Ci,DRXActivity(t) can be used for prioritizing the
scheduling of UEs.
Fig.4 shows an exemplary diagram as how the weighting factor
w(t disti) can be realized as a function of the remaining
time until an end of the "DRX Active" mode is reached. For
example, as shown in Fig.4, in case the time t disti until
the end of the "DRX Active" mode is reached for a particular
UE i amounts to "1" (only little time left), the weighting
factor w is set to "9" (high weighting factor). Hence, the
probability of scheduling this UE i is high as otherwise the
UE may enter the "DRX Sleep" mode and cannot be reached from
the base station within the very same DRX cycle. As another
example, if the time t disti amounts to "2", the weighting
factor w is set to "7" and if the time t disti amounts to
"3", the weighting factor w is set to "5". If the time
t disti amounts to "4", the weighting factor w is set to "3"
and for a time t disti amounting to at least "5", the weight-
ing factor w is set to "1". This indicates that the closer
the end of a "DRX Active" mode, the higher said weighting
factor w becomes.
It is noted that the values shown in Fig.4 are exemplary fig-
ures. The weighting factors may be provided such to fulfill
the following condition
w(t disti) >= w(t disti + 1),
hence, the higher the time duration t disti the lower the
weighting factor. This condition can be optimized for VoIP.
Furthermore, the values of the weighting factor can be set
such that they increase significantly the smaller the time
t disti becomes.
It is noted that the weighting factors may be based on other
criteria as well, e.g., any criterion that can be utilized
for determining a prioritization and/or for scheduling pur-
poses.
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This weighting factor w in particular is of advantage in case
too many UEs are active in a cell and not all UEs can be
served in every subframe. Hence, a decision has to be made to
temporarily remove some UEs from scheduling. Such decision
can be reached based on the prioritization mechanism pre-
sented herein.
Fig.5 shows a network component 501, e.g., a base station, a
gateway, a router, a switch, etc., that is connected to a
network 502. Also, the network component 501 is connected to
a terminal 503 and to a terminal 504. The connection between
the network component 501 and the terminals 503, 504 could be
realized as a radio connection or a connection via a fixed
line.
Traffic (e.g. voice traffic) from the network 502 is sched-
uled by the network component 501 considering the time the
terminals 503, 504 remain in their active mode, i.e. the time
before the terminals 503, 504 enter a sleep mode to save en-
ergy.
If the terminal 503 is about to enter its sleep mode and the
terminal 504 remains in active mode for some more time, the
terminal 503 is scheduled at a higher priority, because of
its impending sleep mode and receives its traffic prior to
the terminal 504, which will be scheduled afterwards. The
scheduling may, as described above, further consider other
parameters as the type of the terminal, the type of data, the
QoS, the channel quality, etc. This may lead to a different
decision, in case due to its type of traffic, the terminal
503 would have been insusceptible to delay, but terminal 504
conducts a VoIP call which is very delay-sensitive.
Also, the terminals 503, 504 may convey information regarding
time information of their sleep modes or active modes to the
network component 501. This information can be utilized when
scheduling the terminals 503, 504. Also, as an option, the
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terminals 503, 504 may send a request to enter the sleep mode
and wait for a confirmation from the network component 501.
This avoids a terminal entering its sleep mode just before it
would have been served with additional data and therefore al-
lows for an efficient power-saving mechanism.
It is noted that the entities shown in Fig.5 could be imple-
mented by a person skilled in the art as various physical
units, wherein the terminal may be a mobile terminal and the
network component could be realized as a the base station.
The terminal or the network component could be realized as or
associated with at least one logical entity that may be de-
ployed as hardware, program code, e.g., software and/or firm-
ware, running on a processing unit, e.g., a computer, micro-
controller, ASIC, FPGA and/or any other logic device.
The functionality described herein may be based on an exist-
ing component of a (wireless) network, which is extended by
means of software and/or hardware. The base station(s) men-
tioned herein could also be referred to as any base station,
base transceiver station or base station controller pursuant
to any communication standard. Accordingly, the mobile device
(mobile terminal, mobile station, UE) may be realized pursu-
ant to any existing or upcoming communication standard.
The approach described allows assigning a scheduling priority
based on a time period unit the mobile or fixed terminal en-
ters the sleep mode. This corresponds to the fact that the
terminal has to be scheduled during its active mode. It is
noted that the active mode may be a portion of a DRX cycle
during which the terminal could be reached by the network
component, in particular the base station.
It is further noted that the solution presented herein can be
applied to LTE and technologies other than LTE. These tech-
nologies other than LTE may in particular comprise upcoming
releases or Standards. Also, the solution may be applied to
all kinds of mobile and/or fixed networks, in particular pro-
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viding corresponding interfaces, timers and/or elements of
architecture.
Further Advantages:
With a considerable likelihood, the delay of transmission is
reduced and/or avoided by efficiently scheduling UEs and
avoiding "DRX Sleep" mode when data is to be conveyed from
the base station to the UE.
Accordingly, the probability for the UE to be scheduled
within its "DRX Active" mode phase is increased. This allows
fulfilling QoS requirements in combination with a DRX func-
tionality. Hence, the approach provides an efficient solution
to offer an improved performance for delay-sensitive traffic
like VoIP.
By appropriately adjusting the weighting factor a tradeoff
between DRX prioritization and other scheduling criteria can
be adjusted meeting individual requirements, e.g. of a net-
work operator and/or a subscriber.
It is an option to provide a weighting factor w that is spe-
cific for classes of UEs providing different capabilities and
for separate services. For example, delay-sensitive traffic
can be scheduled using a higher weighting factor (and thus
resulting in a higher likelihood of traffic being conveyed)
compared to best effort traffic. This allows considering de-
lay-sensitive terminals (e.g., mobile terminals conveying
VoIP) with a higher probability in particular in case these
terminals approach the end of their active mode. It is noted,
however, that different bearers may be defined for different
QoS levels, thus the types of services utilized by the termi-
nal may differ, hence the prioritization could be provided
considering such types of services.
CA 02808505 2013-02-15
WO 2012/013215 18 PCT/EP2010/060808
List of Abbreviations:
3GPP 3rd Generation Partnership Project
BS Base Station
DL Downlink
DRX Discontinuous Reception
eNB evolved NodeB
IP Internet Protocol
LIE Long Term Evolution
PDCCH Physical Downlink Control Channel
PDSCH Physical Downlink Shared Channel
PUCCH Physical Uplink Control Channel
PUSCH Physical Uplink Shared Channel
QoS Quality of Service
RRC Radio Resource Control
RRM Radio Resource Management
SFN System Frame Number
IS Technical Specification
UE User Equipment
UL Uplink
VoIP Voice over IP
