WO2017116297A1

WO2017116297A1 - Method and wireless device for enabling communication of uplink data

Info

Publication number: WO2017116297A1
Application number: PCT/SE2016/051240
Authority: WO
Inventors: Oscar Ohlsson; Håkan Palm; Martin Van Der Zee
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2015-12-30
Filing date: 2016-12-09
Publication date: 2017-07-06
Also published as: AR107271A1

Abstract

A method and a wireless device (200) for enabling transmission of uplink data in a wireless communications network (202) where access barring is applied for different access classes according to a barring scheme signalled (2:2) by the network (202A) at predefined intervals. While using a first DRX cycle for applying sleep mode, the wireless device (200) detects (2:3) that its access class is currently barred from accessing the network (202) when triggered to execute transmission of the uplink data. The wireless device (200) then uses a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme. When detecting, while using the second DRX cycle, that its access class is allowed to access the network (202), the wireless device (200) accesses (2:4) the network (202) for transmitting the uplink data according to said barring scheme. By switching to the shorter second DRX cycle, the time it takes until detecting allowed access can be shorter as compared to keeping the first DRX cycle.

Description

METHOD AND WIRELESS DEVICE FOR ENABLING COMMUNICATION OF

UPLINK DATA

Technical field

The present disclosure relates generally to a method and a wireless device, for enabling communication of uplink data in a wireless communications network where access barring is applied for different access classes.

Background

In this disclosure, the term "wireless device" is used to represent any

communication entity capable of radio communication with a wireless

communications network by sending and receiving radio signals, such as e.g. mobile telephones, tablets, laptop computers and Machine Type Communication, MTC, devices also known as Machine-to-Machine, M2M, devices. Another common generic term in this field is "User Equipment, UE" which is frequently used herein as a synonym for wireless device. Further, the term "network node" is used herein to represent any node of a radio network that is operative to communicate radio signals with wireless devices, or to control some network entity having radio equipment for receiving/transmitting the radio signals. The network node in this disclosure could also be referred to as a base station, radio node, e-NodeB, eNB, NB, base transceiver station, access point, etc., depending on the type of network and terminology used. The terms network node and base station are used interchangeably herein.

Discontinuous reception, DRX, is a technique used in wireless communications networks configured according to Long Term Evolution, LTE, for power saving in wireless devices. Low power consumption may be particularly useful for MTC devices, e.g. meters or sensors, which need to operate for a long time without requiring that a battery in the device must be recharged or replaced.

A wireless device, also denoted UE in the following, in idle mode periodically monitors the downlink control channel called the Physical Downlink Control Channel, PDCCH, which is transmitted or broadcasted in a cell by a network node or base station serving the cell. The UE thus monitors the PDCCH according to a predefined period or scheme to receive paging messages or identify whether any system information is updated. Such a period is known as a DRX cycle. During the rest of the period when the UE is not monitoring the PDCCH, the receiver circuitry in the UE can be powered off which allows the UE to save power, also referred to as sleep mode. The default DRX cycle is broadcasted in the cell and has a value of {320, 640, 1280, 2560} milliseconds, ms.

If the UE needs to communicate with the network, it can do so by accessing a Random Access Channel, RACH, which includes sending an access message on the RACH, referred to as random access. The RACH is available for any UE in the cell that needs to access the network and it may happen that two or more UEs sends an access message on the RACH at the same time, resulting in a collision such that some or all of the messages cannot be properly detected by the serving network node. To enable a longer battery lifetime for MTC devices, extended DRX (eDRX) is introduced in the third Generation Partnership Project, 3GPP, Rel-13. A UE supporting eDRX can be configured with a DRX cycle up to 43.69m in

(256x1024ms). The extended DRX cycle is configured by a Mobility Management Entity, MME over Non Access Stratum, NAS, when the UE attaches to the network.

The above-described collision can be largely avoided by employing so-called "access barring" which is applied for different access classes according to a barring scheme signalled by the network to the UEs at predefined intervals. In access barring, different UEs in the cell are thus assigned to different access classes. The barring scheme allows UEs of one access class at a time to transmit on the RACH, which reduces the risk for collisions considerably. Access barring thus prevents the non-allowed UEs from accessing the RACH and thereby eliminates the risk of a synchronized rush of random accesses, i.e. when several UEs send an access message on the RACH at the same time. This also means that the load on the core network is reduced since fewer access requests are being forwarded at the same time from the network node to the MME in the core network.

However, it is a problem that using an eDRX scheme for applying sleep mode may result in considerable delays for a UE that needs to access the network when access barring is applied, since the UE is likely to be asleep during the short period that its access class is allowed to transmit on the RACH. It may thus take several access opportunities until the UE happens to be awake at the same time its access class is allowed to transmit.

Summary

It is an object of embodiments described herein to address at least some of the problems and issues outlined above. It is possible to achieve this object and others by using a method and a wireless device as defined in the attached independent claims.

According to one aspect, a method is performed by a wireless device for enabling transmission of uplink data in a wireless communications network where access barring is applied for different access classes according to a barring scheme signalled by the wireless communications network at predefined intervals. In this method the wireless device uses a first Discontinuous Reception, DRX, cycle for applying sleep mode. While using the first DRX cycle, the wireless device detects that an access class assigned to the wireless device is currently barred from accessing the network according to said barring scheme when the wireless device is triggered to execute transmission of the uplink data. When this situation occurs, the wireless device starts to use a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode. While using the second DRX cycle, the wireless device then accesses the wireless communications network for transmitting the uplink data when detecting that said access class is allowed to access the wireless

communications network according to said barring scheme.

According to another aspect, a wireless device is arranged to enable transmission of uplink data in a wireless communications network where access barring is applied for different access classes according to a barring scheme signalled by the wireless communications network at predefined intervals. The wireless device is configured to use a first Discontinuous Reception, DRX, cycle for applying sleep mode, which functionality may be realized by means of a DRX module in the network node. The wireless device is configured to detect, while using the first DRX cycle, that an access class assigned to the wireless device is currently barred from accessing the wireless communications network according to said barring scheme when the wireless device is triggered to execute transmission of the uplink data. This functionality may be realized by means of a detecting module in the network node.

The wireless device is further configured to use a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode. This functionality may be realized by means of the above DRX module. The wireless device is also configured to access the network for transmitting the uplink data when detecting, while using the second DRX cycle, that said access class is allowed to access the wireless

communications network according to said barring scheme. This functionality may be realized by means of an accessing module in the network node.

The above method and wireless device may be configured and implemented according to different optional embodiments to accomplish further features and benefits, to be described below.

A computer program is also provided which comprises instructions which, when executed on at least one processor, cause the at least one processor to carry out the method described above. A carrier containing the above computer program is further provided, wherein the carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium.

Brief description of drawings

The solution will now be described in more detail by means of exemplary embodiments and with reference to the accompanying drawings, in which: Fig. 1 is a diagram illustrating how a wireless device typically applies sleep mode, according to the prior art.

Fig. 2 is a communication scenario illustrating an example where the solution may be employed, according to some possible embodiments. Fig. 3 is a flow chart illustrating a procedure in a wireless device, according to further possible embodiments.

Fig. 4 is a flow chart illustrating a more detailed example of a procedure in a wireless device, according to further possible embodiments.

Fig. 5 is a diagram illustrating an example of how a wireless device may apply sleep mode when the solution is used, according to further possible embodiments.

Fig. 6 is a block diagram illustrating a wireless device in more detail, according to further possible embodiments.

Detailed description

The above-described mechanism of access barring, sometimes referred to as Extended Access Barring, EAB, was introduced in 3GPP, Rel-1 1 to avoid overload in the network due to many UEs accessing the network. The mechanism of access barring will now be described in more detail with reference to EAB as an example.

EAB makes use of Access Class, AC, information which is embedded in the Subscriber Identity Module, SIM, used by the device. Ten access classes denoted ACO to AC9 may typically be employed which can be assigned to different UEs so as to allow UEs of one access class at the time to access the network. All UEs are randomly allocated to one of the AC between AC 0 and AC 9. Furthermore, the operator of the network has to enable EAB in the UE in order for the EAB check to take place. This can be done by either setting a special flag in a USIM or by using over-the-air configuration. Typically EAB may only be enabled for delay tolerant MTC devices.

Only mobile originated communications, such as transmission of uplink data from the UE, may be subject to EAB. Before accessing the network the UE checks a 10 bit barring bitmap, also referred to as an EAB bitmap, which is signalled from the network in a System Information Block denoted SIB14, and the UE only proceeds with the access attempt if the bit corresponding to its access class is not set to indicate barred access. By setting/unsetting bits in the EAB bitmap to indicate barred/unbarred, respectively, for corresponding access classes, the network load can be adjusted. Another System Information Block denoted SIB1 is used to indicate whether the EAB bitmap is updated or not, and the wireless device may check SIBI and if EAB is enabled therein, it acquires SIB14 to check the updated EAB bitmap to see if the wireless device's access class is barred or not. To allow all UEs to eventually access the network, the network needs to rotate the access classes in the EAB bitmap by unsetting the bits therein one at a time. UEs in the cell are notified about updates to the EAB bitmap in SIB14 via a Paging message containing an EAB change notification called the eab-ParamModification. When the UE receives the EAB change notification, it acquires both SIB1 and SIB14 immediately.

Fig. 1 illustrates how a wireless device applies sleep mode using the above- described extended DRX, and how the wireless device can miss the time window in which an access class assigned to the wireless device is allowed to access the wireless communications network according to a barring scheme. The network regularly signals EAB change notifications 100 which are illustrated as downward arrows. Basically, an EAB change notification informs wireless devices that the barring scheme has been updated and that the wireless devices need to check the changed barring scheme, e.g. the EAB bitmap in SIB14. It is assumed that the wireless device has been assigned an access class denoted AC-x. In the barring scheme, all wireless devices belonging to access class AC-x are barred from accessing the network during time periods denoted 100A. These periods are terminated when an EAB change notification 100B from the network indicates that the access class AC-x is allowed to access the network until the next EAB change notification indicates that the access class AC-x is barred again. This leaves a limited period 100C, i.e. time window, during which the access class AC-x is allowed to access the network. Numeral 102 denotes the extended DRX scheme used by the wireless device for applying sleep mode which indicates that the wireless device wakes up

periodically to monitor paging at regular occasions denoted 102A, 102B, 102C, 102D, etc. Numeral 104 denotes that the wireless device detects uplink data that should be transmitted once it can detect that the access class AC-x is allowed to access the network. In this description, the term "uplink data" represents any information and messages that the wireless device needs to transmit over the wireless network, e.g. including payload data and signaling messages.

As it happens in this example, none of the wake-up occasions 102B, 102C, 102D in the eDRX scheme after detecting uplink data occurs when an EAB change notification 100B from the network indicates that the access class AC-x is allowed to access the network, i.e. at any of the time windows 100C. As a result, the wireless device will find that the access class AC-x is barred from access each time it wakes up for monitoring while being asleep every time the EAB change notification 100B occurs. It may thus take very long time, i.e. several eDRX cycles, before the wireless device wakes up in time to find that the access class AC-x is allowed to access the network. In the worst case, the wireless device may never detect that its access class AC-x is allowed due to the above schemes and the data can thus never be transmitted. It is thus a problem that using an eDRX scheme for applying sleep mode may result in considerable delays or even missed communication when there is uplink data to transmit from a wireless device in a network where access barring is applied for different access classes according to a barring scheme.

Briefly described, a solution is provided to ensure that a wireless device is able to transmit uplink data without excessive delay in a wireless communications network where access barring is applied for different access classes according to a barring scheme, even when the wireless device uses extended DRX. It is likely that eDRX and EAB will be used at the same time in practice since both are MTC features. The solution can thus be used to avoid that the wireless device frequently or constantly misses the time window in which an access class assigned to the wireless device is allowed to access the wireless communications network according to the barring scheme. Such a time window with allowed access was denoted 100C in Fig. 1 . This can be accomplished by a procedure in the wireless device which will now be described with reference to a communication scenario in Fig. 2. This procedure involves a wireless device 200 which is served by network node 202A in a wireless communications network 202 where access barring is applied for different access classes according to a barring scheme signalled by the wireless communications network at predefined intervals. It is assumed that a certain access class has been assigned to the wireless device 200. Initially, the wireless device 200 uses a first DRX cycle for applying sleep mode, as indicated by a first action 2:1.

Another action 2:2 in Fig. 2 illustrates that the network node 202A signals barring information at regular occasions to indicate that the barring of access classes has changed. In a next action 2:3, the wireless device 200 detects, while using the first DRX cycle, that the access class assigned to the wireless device 200 is currently barred from accessing the network according to said barring scheme when the wireless device 200 is triggered to execute a communication.

When the wireless device 200 needs to access the network to transmit uplink data while being barred from accessing the network, the wireless device 200 uses a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme by applying sleep mode according to the second DRX cycle. Thereby, the risk of missing a time window in which the wireless device 200 is allowed to access the network is greatly reduced since the device 200 will wake up much more often than when using the first DRX cycle. Another action 2:4 illustrates that the wireless device 200 is able to access the network 202 for transmitting the uplink data when detecting, while using the second DRX cycle, that the access class assigned to device 200 is allowed to access the wireless communications network according to said barring scheme.

An example will now be described, with reference to the flow chart in Fig. 3, of how the solution may be employed in terms of actions which may be performed in a wireless device, for enabling transmission of uplink data in a wireless

communications network where access barring is applied for different access classes according to a barring scheme signalled by the wireless communications network at predefined intervals. Without limiting the described features and embodiments, reference will also be made to the example scenario shown in Fig. 2.

A first action 300 illustrates that the wireless device 200 uses a first DRX cycle for applying sleep mode, which corresponds to action 2: 1 above. In a next action 302, the wireless device 200 detects, while using the first DRX cycle, that an access class AC-x assigned to the wireless device 200 is currently barred from accessing the network according to said barring scheme when the wireless device 200 is triggered to execute transmission of the uplink data. This action 302 corresponds to action 2:3 above.

In another action 304, the wireless device 200 uses a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode. Another action 306 illustrates that the wireless device 200 is able to access the wireless communications network 202 for transmitting the uplink data when detecting, while using the second DRX cycle, that said access class AC-x is allowed to access the wireless communications network 202 according to said barring scheme. This action 306 corresponds to action 2:4 above.

Several optional embodiments are possible to employ in the above-described procedure as follows. In one possible embodiment, when using the second DRX cycle, the wireless device 200 may continue to use the first DRX cycle for monitoring paging related to downlink traffic while using the second DRX cycle for monitoring notifications related to the barring scheme. Thus, in this embodiment the wireless device 200 uses both the first and second DRX cycles in parallel. In another possible embodiment, when said communication has been executed, the wireless device 200 may resume using the first DRX cycle for applying sleep mode. In another possible embodiment, the first DRX cycle may be an extended DRX, eDRX, cycle. In another possible embodiment, the second DRX cycle may be a default DRX cycle broadcasted from the wireless communications network.

In another possible embodiment, the wireless device 200 may be triggered to acquire the barring scheme when receiving a change notification signalled from the wireless communications network, e.g. as shown in action 2:2, while the wireless device 200 uses the second DRX cycle. In another possible embodiment, which is a variant of the preceding embodiment, the received change notification may trigger the wireless device 200 to acquire the barring scheme in a barring bitmap comprising a bit for each access class indicating whether said access class is barred or unbarred. In another possible embodiment, which may be used in the two preceding embodiments, the wireless device 200 may receive the change notification and acquire the barring scheme when signalled from a serving network node 202A of the wireless communications network 202. In another possible embodiment, the wireless device 200 may be triggered to use the second DRX cycle when detecting the uplink data to transmit and that the access class assigned to the wireless device 200 is currently barred from accessing the network.

A more detailed example of how the wireless device may operate in the above procedure will now be described with reference to the flow chart in Fig. 4. A first action 400 illustrates that the wireless device uses the first DRX cycle for applying sleep mode, which corresponds to action 300 above. In a next action 402, the wireless device detects that there is uplink data to transmit.

The wireless device then checks in an action 404 whether the access class, AC, assigned to the wireless device is currently barred from accessing the network or not. If not, the wireless device can proceed to access the network and transmit the data, in an action 406. If the wireless device's access class is found to be barred from access in action 404, corresponding to action 302 above, the wireless device starts to use the shorter second DRX cycle for applying sleep mode in an action 408, which corresponds to action 304 above. The wireless device again checks in an action 410 whether the access class, AC, assigned to the wireless device is still barred from accessing the network or not, using the second DRX cycle. If not barred, the wireless device can move to action 406 to access the network and transmit the data, which corresponds to action 306 above. If the wireless device's access class is again found to be barred from access in action 410, the wireless device will repeat actions 408 and 410 until the wireless device's access class is not barred from access during a time window and action 406 can be eventually executed. Once action 406 has been executed and all uplink data has been transmitted, the wireless device can return to action 400 and resume the first DRX cycle for applying sleep mode.

Fig. 5 illustrates how a wireless device can apply sleep mode according to the above-described procedure of Fig. 3, and how the wireless device can wake up and use the time window in which an access class AC-x assigned to the wireless device is allowed to access the network according to the barring scheme. The network regularly signals EAB change notifications 500. White arrows illustrate EAB change notifications which indicate that the access class AC-x assigned to the device is barred from accessing the network during a time period 500A. These EAB change notifications may thus indicate, via the barring scheme, that other access classes than AC-x are allowed, one at a time, to access the network which implies that access class AC-x is barred from accessing the network. Then an EAB change notification from the network, illustrated by a dotted arrow, indicates that the access class AC-x is allowed to access the network during a time window 500B, until the next EAB change notification indicates that the access class AC-x is barred again, not shown. At numeral 502, the wireless device wakes up to monitor paging according to the first DRX cycle, DRX1 . Numeral 504 denotes that the wireless device detects uplink data that should be transmitted once it can detect that the access class AC- x is allowed to access the network. Each time when waking up from sleep mode, the wireless device may check SIB1 to see if EAB is enabled and if that is the case, it acquires SIB14 to see whether its access class is barred from network access or not according to the barring scheme, which may be referred to as an ΈΑΒ check". At numeral 506, the wireless device detects, while using the first DRX cycle, that its access class AC-x is currently barred from accessing the network, which corresponds to action 302. The wireless device then starts to use the shorter second DRX cycle, DRX2, for applying sleep mode for monitoring notifications related to the barring scheme, which corresponds to action 304 above.

After checking the notifications from the network a number of times according to the second DRX cycle DRX2, the wireless device finds, at numeral 508, that its access class AC-x is allowed to access the network. It should be noted that the time it takes before the wireless device manages to check an EAB change notification at the same time the access class AC-x is allowed to access the network, is likely to be considerably shorter than when using the longer first DRX cycle, DRX1 . The wireless device then accesses the network and transmits the data at numeral 510 which is within the time window 500B. Once the transmission is finished, the wireless device resumes to use the first DRX cycle, DRX1 for applying sleep mode for monitoring paging related to downlink traffic, as indicated by numeral 512.

It will now be described in more detail how the above-mentioned actions and embodiments can be implemented to achieve the advantage of reduced risk for excessive delays of transmitting data in a network where access barring is applied for different access classes. In the following the term UE is used as a synonym for wireless device.

An eDRX UE that finds its access class to be barred thus temporarily assumes a shorter DRX cycle DRX2 for the purpose to be able to receive EAB change notifications. In this way the UE is notified when the EAB information has been changed, such that UE can discover if EAB is still in effect in the cell (SIB14 is being broadcast) and, if in effect acquire SIB14 to detect when its access class becomes unbarred. After the access is completed the UE can return to using its extended DRX cycle DRX1 . One option is to use the cell default DRX cycle as the short DRX cycle DRX2, but also other periods are possible e.g. depending on

UE implementation or configured by the network. Another possible solution is that a EAB-barred UE simply re-acquires SIB14 at regular time intervals.

In 3GPP Rel-13, a procedure is defined to notify UEs about EAB changes. With this notification method, the "EAB param modification" information is carried by an information bit which is provided by the network outside the actual Paging message, meaning the UEs can be notified without transmission of actual Paging messages.

This procedure is specified by 3GPP as follows:

RAN1#82bis agreement:

• In each Paging Occasion (PO), an RRC idle UE monitors one DCI type

• The DCI include an indication (e.g. S_flag)

• An indication (e.g. S_flag) used in the DCI with P-RNTI for paging

• If S_flag=TRUE, the rest of DCI bits carries scheduling

information of PDSCH for paging message

• If S_flag=FALSE, the rest of DCI bits carries system information update, ETWS, CMAS, and EAB without scheduling information of PDSCH

Some problems with the existing procedures, including the new 3GPP Rel-13 procedure described above, that have been recognized herein, will be further explained below. A UE configured with eDRX is expected to check the EAB bitmap before a mobile originated call. If the UE finds its access class to be barred it will not trigger any signaling to network for this access attempt until the UE is no longer subject to EAB barring (e.g. the bitmap is "rotated" such that the access class of the UE is no longer barred, or EAB is no longer in effect in the cell).

However, since the existing procedure in 3GPP is to notify UE about EAB changes, e.g. via paging and a "bit" in the paging message, the UE may have to wait one full eDRX cycle (i.e. up to 43.6min) until it can receive such a

notification. Since the EAB bitmap is typically rotated much faster than that, e.g. in the order of a few seconds, there is also a risk that the UE misses the time window during which its access class is unbarred. In the worst case the UE may never discover that EAB information has been changed and hence never be allowed to access the network.

Currently, the 3GPP specifications do not describe any mechanism by which an eDRX UE that is barred from accessing the system via EAB discovers that EAB information is changed. It was described above how a wireless device or UE may operate to achieve the advantages of this solution, e.g. with reference to an example shown in Fig. 5. Note that Fig. 5 only illustrates the principle and the shown relative lengths of the first and second DRX cycles are not to scale. In this solution, the UE may operate according to the following steps or actions 1 -5. 1 . The UE monitors paging according to its extended first DRX cycle DRX1 , as shown by numeral 502.

2. At some point in time new uplink data arrives in the buffer of the UE, as

shown by numeral 504, which triggers the UE to access the network and perform a mobile originated call which involves transmission of the uplink data. Before the access is made, the UE checks the EAB bitmap in SIB14 and finds that its access class is currently barred, as shown by numeral 506. Since the EAB check indicated that access is barred, the UE is forced to wait with performing the access.

3. The failed EAB check causes the UE to temporarily adopt a shorter second DRX cycle, i.e. DRX2, for the purpose to receive information about modified

EAB information. In this example the shorter DRX cycle DRX2 is the default DRX cycle broadcasted in SIB2 (but it can also be any other cycle). The UE monitors paging according to the default DRX cycle and each time it receives an EAB change notification it immediately re-acquires SIB14 and checks if its access class has been unbarred. During this period 500A, the UE continues to monitor paging according to the extended first DRX cycle DRX1 , to detect any paging for mobile terminated calls directed to the UE.

4. Eventually the UEs access class is unbarred, i.e. "allowed", at numeral 508 and the UE will be able to access the network and complete the mobile originated call by transmitting the uplink data pending in the buffer, as shown by numeral 510.

5. When the UE returns to idle mode after completing to mobile originated call it will again monitor paging using its extended first DRX cycle DRX1 , as shown by numeral 512.

Fig. 5 thus illustrates how an eDRX UE with pending uplink data monitors paging using a shorter DRX cycle in case the EAB check fails. Each time it receives an EAB change notification it immediately checks if its access class has been unbarred. Eventually the EAB check will succeed and the UE will be able to complete its call. When the UE returns to idle mode it will again monitor paging using its extended DRX cycle.

An eDRX UE that fails the EAB check is temporarily configured with a shorter DRX cycle to be able to receive EAB change notifications. In this way the UE is notified when the EAB bitmap is changed, e.g. rotated, and is able to detect when its access class becomes unbarred. After the access is completed the UE can return to using its extended DRX cycle.

The block diagram in Fig. 6 illustrates a detailed but non-limiting example of how a wireless device 600 may be structured to bring about the above-described solution and embodiments thereof. The wireless device 600 may be configured to operate according to any of the examples and embodiments of employing the solution as described above, where appropriate, and as follows. The wireless device 600 is shown to comprise a processor "P", a memory "M" and a communication circuit "C" with suitable equipment for communicating radio signals in the manner described herein.

The communication circuit C in the wireless device 600 comprises equipment configured for communication with a serving base station or network node 602 of a wireless communications network, e.g. using a suitable protocol for radio communication depending on the implementation. The solution is however not limited to any specific types of networks, communication technology or protocols.

The wireless device 600 comprises means configured or arranged to perform at least some of the actions 300-306 and 400-410 of the flow charts in Figs 3 and 4, respectively. The wireless device 600 is arranged to enable communication of uplink data in a wireless communications network where access barring is applied for different access classes according to a barring scheme signalled by the wireless communications network at predefined intervals. The wireless device 600 may thus comprise the processor P and the memory M, said memory comprising instructions executable by said processor, whereby the wireless device 600 is operative as follows.

The wireless device 600 is configured to use a first Discontinuous Reception, DRX, cycle for applying sleep mode. This operation may be performed by a DRX module 600A in the wireless device 600, e.g. in the manner described for action 300 above. The wireless device 600 is further configured to detect, while using the first DRX cycle, that an access class assigned to the wireless device 600 is currently barred from accessing the network according to said barring scheme when the wireless device 600 is triggered to execute a communication. This operation may be performed by a detecting module 600B in the wireless device 600, e.g. as in action 302 above.

The wireless device 600 is also configured to use a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode. This operation may be performed by the DRX module 600A, e.g. as described for action 304 above. The wireless device 600 is further configured to access the network for transmitting the uplink data when detecting, while using the second DRX cycle, that said access class is allowed to access the wireless communications network according to said barring scheme. This operation may be performed by an accessing module 600C, e.g. as described for action 306 above. It should be noted that Fig. 6 illustrates various functional modules in the wireless device 600, and the skilled person is able to implement these functional modules in practice using suitable software and hardware. Thus, the solution is generally not limited to the shown structures of the wireless device 600, and the functional units 600A-C therein may be configured to operate according to any of the features and embodiments described in this disclosure, where appropriate.

The functional units 600A-C described above can be implemented in the wireless device 600 by means of program modules of a computer program comprising code means which, when run by the processor P causes the wireless device 600 to perform the above-described actions and procedures. The processor P may comprise a single Central Processing Unit, CPU, or could comprise two or more processing units. For example, the processor P may include a general purpose microprocessor, an instruction set processor and/or related chips sets and/or a special purpose microprocessor such as an Application Specific Integrated Circuit, ASIC. The processor P may also comprise a storage for caching purposes. Each computer program may be carried by a computer program product in the wireless device 600 in the form of a memory having a computer readable medium and being connected to the processor P. The computer program product or memory M in the wireless device 600 thus comprises a computer readable medium on which the computer program is stored e.g. in the form of computer program modules or the like. For example, the memory M may be a flash memory, a Random-Access Memory, RAM, a Read-Only Memory, ROM, an Electrically Erasable Programmable ROM, EEPROM, or hard drive storage, and the program modules could in alternative embodiments be distributed on different computer program products in the form of memories within the wireless device 600. The solution described herein may be implemented in the wireless device 600 by means of a computer program storage product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions according to any of the above embodiments, where appropriate.

ABBREVIATIONS

DRX Discontinuous reception

EAB Extended Access Barring eDRX Extended DRX eNB Evolved node B

LTE Long term evolution

MME Mobility Management Entity

MO Mobile originated

MTC Machine-Type Communications NAS Non Access Stratum

PDCCH Physical Downlink Control Channel

SIB System Information Block

UE User Equipment

While the solution has been described with reference to specific exemplifying embodiments, the description is generally only intended to illustrate the inventive concept and should not be taken as limiting the scope of the solution. For example, the terms "wireless device", "wireless communications network",

"communication", "DRX cycle", "access barring", "Extended Access Barring, EAB", "Access Class, AC" and "barring scheme" have been used throughout this disclosure, although any other corresponding entities, functions, and/or parameters could also be used having the features and characteristics described here. The solution is defined by the appended claims.

Claims

1 . A method performed by a wireless device (200) for enabling transmission of uplink data in a wireless communications network (202) where access barring is applied for different access classes according to a barring scheme signalled by the wireless communications network (202) at predefined intervals, the method comprising:

- using (300) a first Discontinuous Reception, DRX, cycle for applying sleep mode,

- detecting (302), while using the first DRX cycle, that an access class (AC-x) assigned to the wireless device (200) is currently barred from accessing the network according to said barring scheme when the wireless device (200) is triggered to execute transmission of the uplink data,

- using (304) a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode, and - accessing (306) the wireless communications network (202) for transmitting the uplink data when detecting, while using the second DRX cycle, that said access class (AC-x) is allowed to access the wireless communications network (202) according to said barring scheme.

2. A method according to claim 1 , wherein when using the second DRX cycle the wireless device (200) continues to use the first DRX cycle for monitoring paging related to downlink traffic while using the second DRX cycle for monitoring notifications related to the barring scheme .

3. A method according to claim 1 or 2, wherein when said communication has been executed the wireless device (200) resumes using the first DRX cycle for applying sleep mode.

4. A method according to any of claims 1 -3, wherein the first DRX cycle is an extended DRX, eDRX, cycle.

5. A method according to any of claims 1 -4, wherein the second DRX cycle is a default DRX cycle broadcasted from the wireless communications network (202).

6. A method according to any of claims 1 -5, wherein the wireless device (200) is triggered to acquire the barring scheme when receiving a change notification signalled from the wireless communications network (202) while the wireless device (200) uses the second DRX cycle.

7. A method according to claim 6, wherein the received change notification triggers the wireless device (200) to acquire the barring scheme in a barring bitmap comprising a bit for each access class indicating whether said access class is barred or unbarred.

8. A method according to claim 6 or 7, wherein the wireless device (200) receives the change notification and acquires the barring scheme when signalled from a serving network node (202A) of the wireless communications network (202).

9. A method according to any of claims 1 -8, wherein the wireless device (200) is triggered to use the second DRX cycle when detecting the uplink data to transmit and that the access class assigned to the wireless device 200 is currently barred from accessing the network.

10. A wireless device (600) arranged to enable transmission of uplink data in a wireless communications network where access barring is applied for different access classes according to a barring scheme signalled by the wireless

communications network at predefined intervals, wherein the wireless device (600) is configured to: - use (600A) a first Discontinuous Reception, DRX, cycle for applying sleep mode,

- detect (600B), while using the first DRX cycle, that an access class (AC-x) assigned to the wireless device (200) is currently barred from accessing the wireless communications network according to said barring scheme when the wireless device (200) is triggered to execute transmission of the uplink data,

- use (600A) a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode, and

- access (600C) the network for transmitting the uplink data when detecting, while using the second DRX cycle, that said access class (AC-x) is allowed to access the wireless communications network according to said barring scheme.

1 1 . A wireless device (600) according to claim 10, wherein when using the second DRX cycle the wireless device (600) is configured to continue to use the first DRX cycle for monitoring paging related to downlink traffic while using the second DRX cycle for monitoring notifications related to the barring scheme .

12. A wireless device (600) according to claim 10 or 1 1 , wherein when said communication has been executed the wireless device (600) is configured to resume using the first DRX cycle for applying sleep mode.

13. A wireless device (600) according to any of claims 10-12, wherein the first DRX cycle is an extended DRX, eDRX, cycle.

14. A wireless device (600) according to any of claims 10-13, wherein the second DRX cycle is a default DRX cycle broadcasted from the wireless communications network.

15. A wireless device (600) according to any of claims 10-14, wherein the wireless device (600) is configured to be triggered to acquire the barring scheme when receiving a change notification signalled from the wireless communications network while the wireless device (600) uses the second DRX cycle.

16. A wireless device (600) according to claim 15, wherein the wireless device (600) is configured to be triggered by the received change notification to acquire the barring scheme in a barring bitmap comprising a bit for each access class indicating whether said access class is barred or unbarred.

17. A wireless device (600) according to claim 15 or 16, wherein the wireless device (200) is configured to receive the change notification and acquire the barring scheme when signalled from a serving network node (202A) of the wireless communications network (202).

18. A wireless device (600) according to any of claims 10-17, wherein the wireless device (600) is configured to be triggered to use the second DRX cycle when detecting the uplink data to transmit and that the access class assigned to the wireless device 200 is currently barred from accessing the network.

19. A computer program comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 1 -9.

20. A carrier containing the computer program of claim 19, wherein the carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium.

21 . A wireless device (600) arranged to enable transmission of uplink data in a wireless communications network where access barring is applied for different access classes according to a barring scheme signalled by the wireless

communications network at predefined intervals, the wireless device (600) comprising: - a DRX module (600A) configured to use a first Discontinuous Reception, DRX, cycle for applying sleep mode,

- a detecting module (600B) configured to detect, while using the first DRX cycle, that an access class (AC-x) assigned to the wireless device (200) is currently barred from accessing the wireless communications network according to said barring scheme when the wireless device (200) is triggered to execute

transmission of the uplink data, - the DRX module (600A) being further configured to use a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode, and

- an accessing module (600C) configured to access the network for transmitting the uplink data when detecting, while using the second DRX cycle, that said access class (AC-x) is allowed to access the wireless communications network according to said barring scheme.

22. A wireless device (600) according to claim 21 , wherein when using the second DRX cycle the wireless device (600) is configured to continue to use the first DRX cycle for monitoring paging related to downlink traffic while using the second DRX cycle for monitoring notifications related to the barring scheme .

23. A wireless device (600) according to claim 21 or 22, wherein when said communication has been executed the wireless device (600) is configured to resume using the first DRX cycle for applying sleep mode.

24. A wireless device (600) according to any of claims 21 -23, wherein the first DRX cycle is an extended DRX, eDRX, cycle.

25. A wireless device (600) according to any of claims 10-13, wherein the second DRX cycle is a default DRX cycle broadcasted from the wireless communications network.

26. A wireless device (600) according to any of claims 21 -25, wherein the wireless device (600) is configured to be triggered to acquire the barring scheme when receiving a change notification signalled from the wireless communications network while the wireless device (600) uses the second DRX cycle.

27. A wireless device (600) according to claim 26, wherein the wireless device (600) is configured to be triggered by the received change notification to acquire the barring scheme in a barring bitmap comprising a bit for each access class indicating whether said access class is barred or unbarred.

28. A wireless device (600) according to claim 26 or 27, wherein the wireless device (200) is configured to receive the change notification and acquire the barring scheme when signalled from a serving network node (202A) of the wireless communications network (202).

29. A wireless device (600) according to any of claims 21 -28, wherein the wireless device (600) is configured to be triggered to use the second DRX cycle when detecting the uplink data to transmit and that the access class assigned to the wireless device 200 is currently barred from accessing the network.

30. A wireless device (600) arranged to enable transmission of uplink data in a wireless communications network where access barring is applied for different access classes according to a barring scheme signalled by the wireless

communications network at predefined intervals, the wireless device (600) comprising a processor (P) and a memory (M) containing instructions executable by the processor whereby the wireless device (600) is configured to: - use (600A) a first Discontinuous Reception, DRX, cycle for applying sleep mode,

- detect (600B), while using the first DRX cycle, that an access class (AC-x) assigned to the wireless device (200) is currently barred from accessing the wireless communications network according to said barring scheme when the wireless device (200) is triggered to execute transmission of the uplink data, - use (600A) a second DRX cycle which is shorter than the first DRX cycle, for monitoring notifications related to the barring scheme when applying sleep mode, and

31 . A wireless device (600) according to claim 30, wherein when using the second DRX cycle the wireless device (600) is configured to continue to use the first DRX cycle for monitoring paging related to downlink traffic while using the second DRX cycle for monitoring notifications related to the barring scheme .

32. A wireless device (600) according to claim 30 or 31 , wherein when said communication has been executed the wireless device (600) is configured to resume using the first DRX cycle for applying sleep mode.

33. A wireless device (600) according to any of claims 30-32, wherein the first DRX cycle is an extended DRX, eDRX, cycle.

34. A wireless device (600) according to any of claims30-33, wherein the second DRX cycle is a default DRX cycle broadcasted from the wireless communications network.

35. A wireless device (600) according to any of claims 30-34, wherein the wireless device (600) is configured to be triggered to acquire the barring scheme when receiving a change notification signalled from the wireless communications network while the wireless device (600) uses the second DRX cycle.

36. A wireless device (600) according to claim 35, wherein the wireless device (600) is configured to be triggered by the received change notification to acquire the barring scheme in a barring bitmap comprising a bit for each access class indicating whether said access class is barred or unbarred.

37. A wireless device (600) according to claim 35 or 36, wherein the wireless device (200) is configured to receive the change notification and acquire the barring scheme when signalled from a serving network node (202A) of the wireless communications network (202).

38. A wireless device (600) according to any of claims 30-37, wherein the wireless device (600) is configured to be triggered to use the second DRX cycle when detecting the uplink data to transmit and that the access class assigned to the wireless device 200 is currently barred from accessing the network.