WO2013131264A1

WO2013131264A1 - Group sps design for low cost mtc devices

Info

Publication number: WO2013131264A1
Application number: PCT/CN2012/072081
Authority: WO
Inventors: Jing HAN; Na WEI; Haiming Wang; Chunyan Gao; Wei Bai; Shuang TAN
Original assignee: Renesas Mobile Corporation
Priority date: 2012-03-08
Filing date: 2012-03-08
Publication date: 2013-09-12

Abstract

An apparatus and a method are provided by which network devices are allocated to a group of network devices, and scheduling of resources is performed commonly for the group of network devices. Scheduling may be semi persistent scheduling (SPS), for example.

Description

GROUP SPS DESIGN FOR LOW COST MTC DEVICES

Field of the invention

The present invention relates to methods, devices and computer program products for providing a group SPS design for low cost MTC devices.

Background

The following meanings for the abbreviations used in this specification apply:

3GPP 3rd Generation Partnership Project

ACK Acknowledgement

C-RNTI Cell RNTI

eNB Enhanced Node B. Name for Node B in LTE

LTE Long Term Evolution

LTE-A Long Term Evolution Advanced

GRPS General Packet Radio Service

GSM Global System for Mobile Communications

MCS Modulation and Coding Scheme

MTC Machine Type Communication

NACK Negative Acknowledgement

PDCCH Physical Downlink Control Channel

PHICH Physical Hybrid-ARQ Indicator Channel

PUCCH Physical Uplink Control Channel

PUSCH Physical Uplink Shared Channel

RAT Radio Access Technology

RNTI Radio Network Temporary Identifier

RRC Radio Resource Control

SPS Semi-Persistent Scheduling

TPC Transmit Power Control TPC-PUCCH-RNTI Transmit Power Control-Physical Uplink Control Channel-RNTI

TPC-PUSCH-RNTI Transmit Power Control-Physical Uplink Shared

Channel-RNTI

UE User Equipment

UL UpLink

Embodiments of the present invention relate to LTE and LTE-Advance, although not limited thereto. In particular, as LTE deployments evolve, operators would like to reduce the cost of overall network maintenance by minimizing the number of RATs. Machine-Type Communications (MTC) is a market that is likely to continue expanding in the future. Many MTC devices are targeting low-end (low cost, low data rate) applications that can be handled adequately by GSM/GPRS. Owing to the low cost of these devices and good coverage of GSM/GPRS, there is very little motivation for MTC device suppliers to use modules supporting the LTE radio interface. As more and more MTC devices are deployed in the field, this naturally increases the reliance on GSM/GPRS networks. This will cost operators not only in terms of maintaining multiple RATs, but also prevent operators to reap the maximum benefit out of their spectrum (given the non-optimal spectrum efficiency of GSM/GPRS). Given the likely high number of MTC devices, the overall resource they will need for service provision may be correspondingly significant, and inefficiently assigned.

Therefore, it is necessary to find a solution to ensure that there is a clear business benefit to MTC device vendors and operators for migrating low- end MTC devices from GSM/GPRS to LTE networks. In RP-111112, "Provision of low-cost MTC UEs based on LTE" (Vodafone), it is suggested that solutions using, or evolved from, LTE RAN specifications up to and including Rel-10 shall be investigated and evaluated to clearly understand the feasibility of creating a type of terminal that would permit the cost of terminals tailored for the low-end of the MTC market to be competitive with that of GSM/GPRS terminals targeting the same low-end MTC market. This is agreed to be new study item in 3GPP RANI . A typical use case for low cost MTC devices is smart metering. Smart metering is mainly used for UL periodic reporting, which for example the report cycle is 5 mins, 15 mins, 1 hour, 6 hours, 12 hours and 24 hours etc. Besides, the smart meter density is around 1000/sector quoted from US market (R2-102340, "Smart Grid Traffic Behaviour Discussion", Verizon).

For such smart metering, the data reporting is based on a fixed period and the data amount for each meter is low, e.g . tens of bits. Thus, the overhead of control signaling e.g . PDCCH is considerable.

Semi-Persistent Scheduling (SPS) provides a method to reduce the control signaling overhead for regular small packet. However current specified SPS schemes could not handle efficiently huge number of smart metering devices since SPS configuration and resource allocation is UE specific. So the control signaling overhead is still considerable for SPS activation, SPS release, and even unacceptable if considering adaptive retransmission. Thus an efficient scheduling mechanism is needed to both reduce the control signaling overhead and also efficiently handle huge number of UEs.

Summary

The present invention addresses such situation and to provide measures to provide a network connection of network devices such as MTC devices with low overhead .

Various aspects of examples of the invention are set out in the claims. According to a first aspect of the present invention, there is provided an apparatus which comprises at least one processor, and at least one memory including computer program code, the at least one memory and the computer program being configured to, with the at least one processor, cause the apparatus to allocate network devices to a group of network devices, and to perform scheduling of resources commonly for the group of network devices. According to a second aspect of the present invention, there is provided an apparatus which comprises at least one processor and at least one memory including computer program code, the at least one memory and the computer program being configured to, with the at least one processor, cause the apparatus to receive a group configuration signaling by which the apparatus is allocated to a group of network devices and resources are commonly scheduled for the group of network devices, receive a single control message for the group of the network devices, and perform an operation indicated in the control message. According to a third aspect of the present invention, there is provided a method which comprises

allocating network devices to a group of network devices, and performing scheduling of resources commonly for the group of network devices.

According to a fourth aspect of the present invention, there is provided a method which comprises

receiving a group configuration signaling by which the apparatus is allocated to a group of network devices and resources are commonly scheduled for the group of network devices,

receiving a single control message for the group of the network devices, and

performing an operation indicated in the control message. Advantageous modifications of the above aspects are set out in the dependent claims. According to a fifth aspect of the present invention, a computer program product is provided which comprises computer-executable components which, when executed on a computer, are configured to carry out the method as defined in any one of the third and fourth aspects and their modifications.

Thus, according to embodiments of the present invention, the network devices are allocated to a group, and resources are scheduled for the group of network devices in common. Hence, overhead can largely be reduced.

Brief description of drawings

For a more complete understanding of example embodiments of the present invention, reference is now made to the following descriptions taken in connection with the accompanying drawings in which :

Fig . 1 schematically illustrates an eNB according to an embodiment of the present invention,

Fig . 2 schematically illustrates an UE according to an embodiment of the present invention,

Fig . 3 illustrates an UL SPS configuration,

Fig . 4 shows a group SPS procedure according to an embodiment of the present invention, Fig . 5 shows mixed scheduling of UEs with different SPS intervals according to an embodiment of the present invention,

Fig . 6 shows UE multiplexing in a group SPS resource according to an embodiment of the present invention, and

Fig . 7 shows a group SPS resource lasting for multiple subframes according to an embodiment of the present invention.

Description of exemplary embodiments

Exemplary aspects of the invention will be described herein below. Fig . 1 illustrates a simplified block diagram of an eNB 1 as an example for a network control device according to an embodiment of the present invention. It is noted that the eNB, and the corresponding apparatus according to the embodiment may consist only of parts of the eNB, so that the apparatus may be installed in an eNB, for example. Moreover, also the eNB is only an example and may be replaced by another suitable network element.

The eNB 1 according to this embodiment comprises a processor 11 and a memory 12. The memory comprises a computer program, wherein the memory 12 and the computer program are configured to, with the processor, cause the apparatus allocate network devices to a group of network devices, and to perform scheduling of resources commonly for the group of network devices. That is, scheduling of resources for the network devices is not made separately for each network device, but only for the group as a whole. The scheduling of resources for the group of network devices may be performed such that the resources are fixedly allocated. For example, the resource for the group may be predefined, and this would apply to every nth following subframe. In addition, optionally the allocation may be dynamically modified, when necessary (e.g ., for packet retransmission). Such a scheduling scheme may be semi persistent scheduling (SPS), which is described above.

Hence, the eNB may control the group of network devices by a single control message for the group, that is, a single group activation message for activating the group or a single group release message for releasing the group would be necessary. The single control message may comprise a group index and/or a group network temporary identifier for identifying the group, for example.

Optionally, the eNB 1 may also comprise an interface 13 for providing connections to other network elements. Moreover, the processor 11, the memory 12 and the interface 13 may be inter-connected by a suitable connection 14, e.g ., a bus or the like. Moreover, it is noted that the apparatus may comprise more than one processor, more than one memory and/or more than one interface, if this is suitable for a particular structure.

Fig . 2 illustrates a simplified block diagram of a user equipment (UE) 2 according to an embodiment of the present invention. It is noted that, similar as in case of the eNB described above, the UE and the corresponding apparatus according to the embodiment may consist only of parts of the UE, so that the apparatus may be installed in an UE, for example. Moreover, also the UE is only an example and may be replaced by another suitable network element.

The UE 2 according to this embodiment comprises a processor 21 and a memory 22. The memory comprises a computer program, wherein the memory 22 and the computer program are configured to, with the processor, cause the apparatus to receive a group configuration by which the apparatus is allocated to a group of network devices and resources are commonly scheduled for the group of network devices, to receive a single control message for the group of the network devices, and to perform an operation indicated in the control message.

As also mentioned above in connection with the eNB 1, the resources for the group of network devices may be scheduled such that resources are fixedly allocated, and, optionally, the allocation may be dynamically modified when necessary. This scheduling may be semi persistent scheduling (SPS).

Furthermore, signaling to allocate a network device to the group in radio resource control signaling may be sent from the eNBl to UE(s) for group configuration. The signaling may include a group index and/or a group network temporary identifier.

Optionally, the UE 2 may also comprise an interface 23 for providing connections to other network elements. Moreover, the processor 21, the memory 22 and the interface 23 may be inter-connected by a suitable connection 24, e.g ., a bus or the like. Moreover, it is noted that the apparatus may comprise more than one processor, more than one memory and/or more than one interface, if this is suitable for a particular structure.

Thus, according to embodiments of the present invention, the network devices are allocated to a group, and resources are scheduled for the group of network devices in common, wherein, for example, SPS may be applied . Hence, overhead can largely be reduced. For example, in particular for low cost MTC devices, such a group-based UL SPS mechanism may overcome problems with respect to a large overhead. Before explaining more detailed embodiments of the present invention, first semi-persistent scheduling (SPS) mentioned is described in more detail . In Rel-10, SPS is providing a scheduling method to cope with the traffic with fixed and small packet transmission, e.g . VoIP. For UL SPS, the SPS parameters e.g . SPS interval, SPS implicitly release times, power control parameter etc. are configured by RRC signaling as shown in Fig. 3, which is taken from 3GPP TS 36.331 V9.9.0 (2011-12), chapter 6.3.1.

Besides, some validation bits are set for the PDCCH scrambled with SPS- C-RNTI. The PDCCH format for SPS activation is as shown in the following table 1, which taken from 3GPP TS 36.213 V10.4.0 (2011-12), table 9.2- 1, chapter 9.2.

Table 1 : PDDCH format for SPS activation

When UE is configured by UL SPS and activated by PDCCH, a series of resources is reserved for UE's UL data initial transmission. The UL retransmission for SPS is still the same as with dynamic scheduling, i.e. either non-adaptive retransmission triggered by NACK on PHICH, or adaptive retransmission scheduled by PDCCH scrambled with SPS-C- RNTI. The power control command is carried on PDCCH format 3/3A scrambled with TPC-PUSCH-RNTI or TPC-PUCCH-RNTI.

When the UL traffic is over, UL SPS is released either by implicitly way or explicitly way. By implicitly way, the UE shall clear the configured uplink grant immediately after implicitReleaseAfter number of consecutive new MAC PDUs each containing zero MAC SDUs have been provided by the Multiplexing and Assembly entity, on the Semi-Persistent Scheduling resource; and by explicitly way, if PDCCH scrambled with SPS-C-RNTI indicate the SPS release, UE will clear the configured uplink grant (as defined in 3GPP TS 36.321, Medium Access Control (MAC) protocol specification, for example). The PDCCH format for SPS releases is as is as shown in the following table 2, which taken from 3GPP TS 36.213 V10.4.0 (2011-12), table 9.2-1A, chapter 9.2.

Table 2 : PDCCH format for SPS release

After correctly receiving the PDCCH used for SPS release, the UE will send the ACK to eNB to confirm that the SPS resource has been released. Otherwise, the UE does not send any feedback, and the eNB will retransmit PDCCH to release the SPS again.

In the following, some more detailed embodiments of the present invention are described, according to which a group SPS mechanism design is applied which is based on the current SPS scheme as described above.

First, some points in connection with the group SPS design according to certain embodiments of the present invention are summarized.

1. Grouping for group SPS:

UEs are allocated to a group for group SPS. The group configuration is based on RRC signaling, e.g . during UE initial access.

This group configuration could be included in RRC signaling, for example in RRCConnectionReconfiguration. The group configuration could include SPS group index, group-SPS-C-RNTI, resource position index, resource granularity, UL feedback resource configuration for group SPS release, UL feedback position index etc. 2. Group SPS activation :

A group based PDCCH activation is used, i.e. one PDCCH activation is for a group of UEs. The SPS group index could be indicated in the content of group PDCCH activation signaling in order to distinguish the PDCCH for the SPS group of the UEs. That is, the SPS group index is used to inform UE that the particular SPS activation signaling is for the SPS group to which the UE belongs. As an alternative, group-SPS-C-RNTI could be scrambled for this activation PDCCH signaling.

In PDCCH for the group activation, a resource allocation field is provided, and this resource allocation field is for one SPS group.

The eNB could allocate more than one subframe during one SPS periodicity (or one SPS interval) with one SPS PDCCH, with all the UEs in the group multiplexed. The subframe number for group SPS resource could be configured dynamically or pre-defined in the specification.

3. Resource Allocation :

UEs in the same SPS group have the same amount of resource. Multiple UEs in the same SPS group could be multiplexed by FDM, TDM or hybrid FDM, and multiplexed by TDM in the chunk of resource for one SPS group. The exact resource to be used by a specific UE will be indicated by eNB at the first stage (i.e. using resource position index described above in connection with grouping for group SPS)

4. Group SPS release :

A group based PDCCH release is used, i.e. one PDCCH release is for a group of UEs.

The SPS group index could be indicated in the content of group PDCCH release signaling, in order to distinguish the PDCCH for the SPS group of the UEs. As an alternative, group-SPS-C-RNTI could be scrambled for this release PDCCH

The UL feedback resource is explicitly indicated by eNB. In more detail, the UL feedback resource for a SPS group could be configured in RRC signaling, and the order of UL feedback of specific UE reuses a resource position index or a feedback position index.

5. Scheduling for mixed multiple SPS interval :

UE with different SPS interval could be allocated to the same group and activated together. The SPS intervals for the UEs in the same group may be multiple times of each other, e.g . 10ms, 50ms, lmin, 5min etc. The UEs resource position in the same group may then be according to the ascending or descending order of SPS interval.

In the following, a more detailed implementation of an embodiment of the present invention is described by referring to the flow chart shown in Fig . 4.

In SI, group SPS configuration is carried out. For example, the group SPS is be configured during initial access of each low cost MTC device. For example, group SPS could be configured together with normal SPS configuration, which is in RRCConnectionReconfiguration by earliest. The content of group SPS is including SPS group index, group-SPS-C-RNTI, resource position index, resource granularity index, UL feedback resource configuration for group SPS release, UL feedback position index etc. but is not limited to this content. By this method, low cost MTC devices will be allocated to a SPS group by RRC signaling e.g . during the initial access.

When all UEs in the specific SPS group are successfully configured, the eNB is sending one PDCCH to activate this SPS group, as indicated in S2. This PDCCH is either includes the SPS group index or scrambled with Group-SPS-C-RNTI to distinguish the SPS group by UEs. UEs in the indicated SPS group will do actions that are similar to the normal SPS activation, i.e. reserve the UL grant periodically in time domain. The PDCCH for group SPS activation also has the special format as shown in table 1. Besides, the resource allocated by the PDCCH for group SPS activation is for the SPS group, i.e. all UEs UL transmission in the same group will be multiplexed in this resource. Effective time duration of resource allocation could be included or pre-defined in the specification, which is indicating how long the resource allocation is effective. For example, if the effective time duration is 5 ms, then the resource allocation for this SPS group is lasting for 5ms for each group SPS resource instance.

In S3, it is checked whether all UEs of the group are activated. If this is not the case, the process advances to S4, in which the group SPS activation is resent. If all UEs are activated (the result of S3 is yes), then the process advances to S5, in which group SPS transmission is carried out. In S6, it is checked whether the traffic in connection with the group SPS transmission has ended. If not, the process goes back to S5. Otherwise, i.e., when the traffic has ended, the UEs can be released by sending a group SPS release in S7.

Moreover, UEs with different SPS intervals can be configured within the same SPS group, and also activated together.

Preferably (however not necessarily), the following conditions should be fulfilled :

- The SPS interval of UEs is multiple times for each other in the same group, and

- The UEs resource position in the same group is according to the ascending or descending order of SPS interval.

For example, there are UEs with SPS 20ms, 40ms and 80ms, and UE resource position is according to the ascending order of SPS interval, i.e. UEs with larger SPS interval is allocated with larger position index. Then the transmission of these UEs is as shown in Fig. 5. In the figure, for 0ms and 80ms instance, all three kinds of UE are doing UL transmission. However, for 20ms and 60ms instance only UEs with 20ms SPS periodicity will do the UL transmission. The resources indicated by blank blocks with dotted lines are those resources that can not be used by group SPS users, but these resources could be allocated to other UEs by eNB. So there will be no resource wasting, and UEs with different SPS periodicity could be activated together.

If the PDCCH for group SPS activation is missed for some users in the group, eNB could detect this since these UE do not do UL transmission in the reserved resource. Then eNB could send the PDCCH for group SPS again to reactivate these UEs.

In the reserved group SPS resource, UEs is using the same resource granularity, and using the position index that is configured by RRC signaling. These UEs could be multiplexed by FDM, TDM or hybrid method. Examples for this are illustrated in Fig . 6.

Among these multiplexing methods, FDM way is preferred since it is the most simple and backward compatible way.

Especially for TDM method, multiple UEs could be multiplexed in the same subframe, or each UE could occupy one subframe. Then in such kind of method, group SPS resource will last for multiple subframes during one SPS periodicity (or interval), and the length of this group SPS resource in time domain is indicated by the effective time duration that contains in group PDCCH activation, or specified beforehand. This is illustrated in Fig . 6. In particular, Fig. 6A illustrates TDM, Fig . 6B illustrates FDM, and Fig. 6C illustrates the hybrid FDM & TDM .

In the figure, different blocks stand for different UEs, and each UE will occupy 1ms. The order of UE is based on the resource position index that configured by RRC signaling After the UEs have carried out UL transmission, the UEs will receive a DL feedback that is carried on PHICH, which is totally the same with current SPS procedure. The UEs will carry out a non-adaptive retransmission according to PHICH, or, alternatively, the UEs will carry out an adaptive retransmission according to UE-specific PDCCH, which is also totally the same with current SPS procedure.

After the service end for specific UE, the group SPS resource for specific UE could be released by implicitly way which is totally the same with current SPS implicitly release. That is, each UE can be released separately.

Alternatively, the overall group SPS resource could be released by one PDCCH signaling, as indicated by S7 in Fig. 4 described above. This PDCCH either includes the SPS group index or is scrambled with Group- SPS-C-RNTI to distinguish the SPS group by UEs. After the UEs of the group have received the group release, the UEs in the group will all release the reserved SPS resource. Each UE will send ACK to eNB in the configured UL feedback resource by resource position index or configured feedback position index. eNB will send the PDCCH for group SPS release again for those UEs do not successfully receive the PDCCH for group SPS release. That is, a similar process as shown in Fig. 4 for the group activation process (S3 and S4) could also be carried out for the group release process.

Hence, according to embodiments of the present invention, PDCCH overhead for SPS activation, SPS release etc. can be saved, and efficient SPS scheduling for a huge number of UEs is enabled. The measures as described in the above embodiments are in particular advantageous for smart metering services, which have the same traffic for all UEs, and are not sensitive for delays. It is noted that the invention is not limited to the specific embodiments as described above.

For example, the embodiment described above in connection with Fig. 4 uses SPS as a scheduling scheme. However, also other scheduling schemes are possible, for example a persistent scheduling, in which only fixed resources are allocated, or even a dynamic scheduling, as long as it is possible to group resources of network devices such as UEs.

Embodiments of the present invention may be implemented in software, hardware, application logic or a combination of software, hardware and application logic. The software, application logic and/or hardware generally, but not exclusively, may reside on the devices' modem module. In an example embodiment, the application logic, software or an instruction set is maintained on any one of various conventional computer-readable media. In the context of this document, a "computer- readable medium" may be any media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer or smart phone, or user equipment.

The present invention relates in particular but without limitation to mobile communications, for example to environments under LTE, WCDMA, WIMAX and WLAN and can advantageously be implemented in user equipments or smart phones, or personal computers connectable to such networks. That is, it can be implemented as/in chipsets to connected devices, and/or modems or other modules thereof. If desired, at least some of different functions discussed herein may be performed in a different order and/or concurrently with each other. Furthermore, if desired, one or more of the above-described functions may be optional or may be combined.

Thus, according to certain aspects of embodiments of the present invention, an apparatus and a method are provided by which network devices are allocated to a group of network devices, and scheduling of resources is performed commonly for the group of network devices. Scheduling may be semi persistent scheduling (SPS), for example.

According to a further aspect of embodiments of the present invention, an apparatus is provided which comprises means for allocating network devices to a group of network devices, and means for performing scheduling of resources commonly for the group of network devices.

According to a another aspect of embodiments of the present invention, an apparatus is provided which comprises means for receiving a group configuration signaling by which the apparatus is allocated to a group of network devices and resources are commonly scheduled for the group of network devices, means for receiving a single control message for the group of the network devices, and means for performing an operation indicated in the control message. It is to be understood that any of the above modifications can be applied singly or in combination to the respective aspects and/or embodiments to which they refer, unless they are explicitly stated as excluding alternatives. Although various aspects of the invention are set out in the independent claims, other aspects of the invention comprise other combinations of features from the described embodiments and/or the dependent claims with the features of the independent claims, and not solely the combinations explicitly set out in the claims.

It is also noted herein that while the above describes example embodiments of the invention, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the present invention as defined in the appended claims.

Claims

WHAT IS CLAIMED IS:

1. An apparatus comprising

at least one processor, and

at least one memory including computer program code,

the at least one memory and the computer program being configured to, with the at least one processor, cause the apparatus to allocate network devices to a group of network devices, and to perform scheduling of resources commonly for the group of network devices.

2. The apparatus according to claim 1, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

perform scheduling of resources for the group of network devices such that resources are fixedly allocated, and, optionally, to dynamically modify the allocation when necessary.

3. The apparatus according to claim 2, wherein the scheduling is semi persistent scheduling (SPS).

4. The apparatus according to any one of the claims 1 to 3, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

include group configuration signaling to allocate a network device to the group in radio resource control signaling, wherein the group configuration signaling comprises at least one of the following : a group index and/or a group network temporary identifier, a resource position index, a resource granularity, an uplink feedback resource configuration for group release, and/or an uplink feedback position index.

5. The apparatus according to any one of the claims 1 to 4, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

control the group of network devices by a single control message for the group.

6. The apparatus according to claim 5, wherein the group control message comprises a group index and/or a group network temporary identifier for identifying the group.

7. The apparatus according to claim 5 or 6, wherein the single control message comprises a group activation message or a group release message.

8. The apparatus according to any one of the claims 1 to 7, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

allocate the same amount of resources for each network device in the group of network devices.

9. The apparatus according to any one of the claims 1 to 8, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

multiplex resources for the network devices of the group of network devices by frequency division multiplex and/or time division multiplex.

10. The apparatus according to claim 9, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

indicate an exact resource to be used by a specific network device of the group of network devices upon configuring the group of network devices.

11. The apparatus according to any one of the claims 1 to 10, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

indicate a feedback resource to be used by a specific network device of the group of network devices upon configuring the group of network devices.

12. The apparatus according to any one of the claims 1 to 11, wherein the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to

allocate resources to each network device of the group of network devices with certain interval, wherein the interval may differ between network devices of the same group of network devices.

13. An apparatus comprising

at least one processor

and at least one memory including computer program code, the at least one memory and the computer program being configured to, with the at least one processor, cause the apparatus to receive a group configuration signaling by which the apparatus is allocated to a group of network devices and resources are commonly scheduled for the group of network devices,

receive a single control message for the group of the network devices, and

perform an operation indicated in the control message.

14. The apparatus according to claim 13, wherein the resources for the group of network devices are scheduled such that resources are fixedly allocated, and, optionally, the allocation may be dynamically modified when necessary.

15. The apparatus according to claim 14, wherein the scheduling is semi persistent scheduling (SPS).

16. The apparatus according to any one of the claims 13 to 15, wherein the group configuration signaling comprises a group index and/or a group network temporary identifier.

17. The apparatus according to any one of the claims 13 to 16, wherein the group control message comprises a group index and/or a group network temporary identifier for identifying the group.

18. The apparatus according to any one of the claims 13 to 17, wherein the single control message comprises a group activation message or a group release message.

19. The apparatus according to any one of the claims 13 to 18, wherein the configuration comprises an indication of an resource to be used by the apparatus and/or indication of a feedback resource to be used by the apparatus.

20. The apparatus according to any one of the claims 13 to 19, wherein resources are allocated with certain interval, wherein the interval may differ between the apparatus and one or more network devices of the same group of network devices.

21. A method comprising

22. The method according to claim 21, further comprising performing scheduling of resources for the group of network devices such that resources are fixedly allocated, and, optionally, to dynamically modify the allocation when necessary.

23. The method according to claim 22, wherein the scheduling is semi persistent scheduling (SPS).

24. The method according to any one of the claims 21 to 23, further comprising

including group configuration signaling to allocate a network device to the group in radio resource control signaling, wherein the group configuration signaling comprises at least one of the following : a group index and/or a group network temporary identifier, a resource position index, a resource granularity, an uplink feedback resource configuration for group release, and/or an uplink feedback position index.

25. The method according to any one of the claims 21 to 24, further comprising

controlling the group of network devices by a single control message for the group.

26. The method according to claim 25, wherein the group control message comprises a group index and/or a group network temporary identifier for identifying the group.

27. The method according to claim 25 or 26, wherein the single control message comprises a group activation message or a group release message.

28. The method according to any one of the claims 21 to , further comprising

allocating the same amount of resources for each network device in the group of network devices.

29. The method according to any one of the claims 21 to 28, further comprising

multiplexing resources for the network devices of the group of network devices by frequency division multiplex and/or time division multiplex.

30. The method according to claim 29, further comprising

indicating an exact resource to be used by a specific network device of the group of network devices upon configuring the group of network devices.

31. The method according to any one of the claims 21 to 30, further comprising

indicating a feedback resource to be used by a specific network device of the group of network devices upon configuring the group of network devices.

32. The method according to any one of the claims 21 to 31, further comprising

allocating resources to each network device of the group of network devices with certain interval, wherein the interval may differ between network devices of the same group of network devices.

33. A method comprising

receiving a single control message for the group of the network devices, and

performing an operation indicated in the control message.

34. The method according to claim 33, wherein the resources for the group of network devices are scheduled such that resources are fixedly allocated, and, optionally, the allocation may be dynamically modified when necessary.

35. The method according to claim 34, wherein the scheduling is semi persistent scheduling (SPS).

36. The method according to any one of the claims 33 to 35, wherein the group configuration signaling comprises a group index and/or a group network temporary identifier.

37. The method according to any one of the claims 33 to 36, wherein the group control message comprises a group index and/or a group network temporary identifier for identifying the group.

38. The method according to any one of the claims 33 to 37, wherein the single control message comprises a group activation message or a group release message.

39. The method according to any one of the claims 33 to 38, wherein the configuration comprises an indication of an resource to be used by the apparatus and/or indication of a feedback resource to be used by the apparatus.

40. The method according to any one of the claims 33 to 39, wherein resources are allocated with certain interval, wherein the interval may differ between the apparatus and one or more network devices of the same group of network devices.

41. A computer program product comprising computer-executable components which, when executed on a computer, are configured to carry out the method as defined in any one of the claims 12 to 40.