WO2023156022A1

WO2023156022A1 - Coordinating resources for use in direct communications between user equipment

Info

Publication number: WO2023156022A1
Application number: PCT/EP2022/054285
Authority: WO
Inventors: Ling Yu; Daniel Medina; Nuno Manuel KIILERICH PRATAS; Torsten WILDSCHEK; Vinh Van Phan
Original assignee: Nokia Technologies Oy
Priority date: 2022-02-21
Filing date: 2022-02-21
Publication date: 2023-08-24

Abstract

An apparatus, method and computer program for generating coordination information and an associated priority for use in direct communications between user equipment. The apparatus determines radio resources that are reserved for sidelink transmission by other apparatuses and corresponding priority values associated with the reserved radio resources. The apparatus then generates coordination information indicative of the status of the reserved radio resources and generates a priority value for the coordination information, the priority value being generated in dependence upon at least one of the priority values determined by the apparatus.

Description

COORDINATING RESOURCES FOR USE IN DIRECT COMMUNICATIONS BETWEEN USER EQUIPMENT

TECHNOLOGICAL FIELD

Various example embodiments relate to providing coordination information indicative of the status of radio resources for direct and in particular sidelink communication between user equipment.

BACKGROUND

User equipment (UE) may communicate directly with each other, in some cases using sidelink (SL) channels. Where the communication is not under the control of a network node, the coordination of resources to reduce interference and conflict may be challenging. To address this, coordination information indicative of resources that are reserved for transmissions may be sent between the UEs along with an associated priority value indicative of the priority of the transmissions that are to use the reserved resource. In some cases, such as where a receiving UE is sending coordination information to a transmitting UE then determining a priority for this transmission may not be straightforward.

BRIEF SUMMARY

The scope of protection sought for various embodiments of the disclosure is set out by the independent claims. The embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention.

According to various, but not necessarily all, embodiments of the invention there is provided an apparatus, comprising: means for determining at least one radio resource of a plurality of radio resources that is reserved for sidelink transmission by at least one of a plurality of apparatuses and a corresponding at least one priority value associated with said at least one reserved radio resource; means for generating coordination information indicative of a status of at least one of said plurality of radio resources, said at least one of said plurality of radio resources including said at least one reserved radio resource and for generating a priority value for said coordination information; wherein said means for generating is configured to generate said priority value in dependence upon at least one of said corresponding at least one priority values determined by said means for determining; and means for transmitting said coordination information and said priority value to at least one other apparatus.

Where apparatuses are communicating directly with each other, in some cases using sidelink transmissions, then in order for interference between signals to be avoided or at least reduced it may be desirable if some coordination of resource allocation is performed. This coordination can be aided by the transmission of coordination information between the apparatuses, the coordination information indicating the status of radio resources dedicated for sidelink transmissions. The status maybe indicative of whether the resources are reserved for other transmissions or not. Where an apparatus is generating this coordination information in response to a request from an other apparatus or under network control then it may be that the priority of such a transmission maybe provided to the apparatus. However, where this is not the case then the apparatus may generate its own priority information for transmission with the coordination information that it generates. Embodiments generate both the coordination information and a priority vale by determining radio resources that are currently reserved for transmissions along with corresponding priority values associated with these reserved radio resources. They then base the priority value for the coordination information upon at least one of the priority values that have been determined. They then transmit or broadcast the coordination information to at least one other apparatus, this being an apparatus that is not one of the plurality of apparatus whose reserved resources form the basis of the coordination information. In some example embodiments, the other apparatus may be an apparatus from which transmission of data is expected.

This may be seen as inheriting a priority value of a radio resource that the apparatus is trying to protect. For example, where the apparatus determines that a radio resource is reserved and there is a high priority associated with this reservation then it may choose to transmit information regarding the reserved status of the resource as the coordination information along with a value indicating a high priority.

In some example embodiments, in response to said means for determining a single reserved radio resource, said means for generating is configured to set said priority value for said coordination information to said corresponding priority value associated with said single reserved radio resource. In other embodiments, in response to said means for determining determining multiple reserved radio resources, said means for generating is configured to determine a lowest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information in dependence upon said lowest priority value.

In yet other embodiments, in response to said means for determining determining multiple reserved radio resources, said means for generating is configured to determine said priority value for said coordination information as a function of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information to reflect said function of said corresponding priority values.

Where the determining means detects a single reserved radio resource the priority value associated with this single reserved radio resource may be given to the coordination information that is being generated. Where there are multiple resources that are reserved, then one of the values, may be selected, which may be the highest value or it may be the lowest value or an average or weighted average of the values may be selected, or in some cases the mode value may be chosen.

In some example embodiments, the function may operate on the priority values that are detected while in others it may be the values after they have been adjusted in dependence upon determined signal power or resource congestion.

In some example embodiments, in response to said means for determining determining multiple reserved radio resources, said means for generating is configured to indicate multiple priority values to reflect corresponding priority values associated with said multiple reserved radio resources.

In some example embodiments, in response to said means for determining determining said apparatus is to transmit in a time slot, said means for generating is configured to generate an indication of said time slot as a non-preferred radio resource and to set said priority value for said coordination information to a priority value associated with data to be transmitted by said apparatus in said time slot. In some example embodiments, said means for generating is further configured to determine a measure of radio channel congestion and to adjust said priority value in dependence upon said measure of radio channel congestion.

In some example embodiments, the measure of radio channel congestion may be a channel busy ratio which may be a ratio of the time a channel is busy to the observed time.

In some example embodiments, said means for determining is configured to determine a signal strength associated with a transmission indicating said at least one reserved radio resource and to adjust said priority value for said coordination information in dependence upon said signal strength .

In some example embodiments, the means for determining and generating comprise: at least one processor; and at least one memory including computer program code, the at least one memory and computer program code being configured to, with the at least one processor, cause the performance of the apparatus.

According to various, but not necessarily all, embodiments of the invention there is provided according to one aspect a method comprising determining at least one radio resource of a plurality of radio resources that is reserved for sidelink transmission by at least one of a plurality of apparatuses and a corresponding at least one priority value associated with said at least one reserved radio resource; generating coordination information indicative of a status of at least one of said plurality of radio resources, said at least one of said plurality of radio resources including said at least one reserved radio resource; and generating a priority value for said coordination information in dependence upon at least one of said corresponding at least one priority values; and transmitting said coordination information and said priority value to at least one other apparatus..

In some example embodiments, in response to determining a single reserved radio resource, said method generates said priority value by setting said priority value for said coordination information to said corresponding priority value associated with said single reserved radio resource.

In some example embodiments, in response to determining multiple reserved radio resources, said method determines a highest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and sets said priority value for said coordination information in dependence upon said highest priority value.

In some example embodiments, in response to determining multiple reserved radio resources, said method determines a lowest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and sets said priority value for said coordination information in dependence upon said lowest priority value.

In some example embodiments, in response to determining multiple reserved radio resources, said method determines said priority value for said coordination information as a function of corresponding priority values associated with said multiple reserved radio resources and sets said priority value for said coordination information to reflect said function of said corresponding priority values.

In some example embodiments, in response to determining multiple reserved radio resources, said method indicates multiple priority values within said coordination information to reflect corresponding priority values associated with said multiple reserved radio resources.

In some example embodiments, in response to determining that said apparatus is to transmit in a time slot, said method generates an indication of said time slot as a nonpreferred radio resource and sets said priority value for said coordination information to a priority value associated with data to be transmitted by said apparatus in said time slot.

In some example embodiments, said method comprises determining a measure of radio channel congestion and adjusting said priority value in dependence upon said measure of radio channel congestion.

In some example embodiments, said method comprises determining a signal strength associated with a transmission indicating said at least one reserved radio resource and adjusting said priority value for said coordination information in dependence upon said signal strength . In some example embodiments, said method further comprises transmitting said coordination information and said priority value to a further apparatus.

According to various, but not necessarily all, embodiments of the invention there is provided according to a further aspect a computer program which when executed by a processor on an apparatus is configured to control said apparatus to perform a method according to one aspect.

According to various, but not necessarily all, embodiments of the invention there is provided an apparatus, comprising: determining circuitry configured to determine at least one radio resource of a plurality of radio resources that is reserved for sidelink transmission by at least one of a plurality of apparatuses and a corresponding at least one priority value associated with said at least one reserved radio resource; generating circuitiy configured to generate coordination information indicative of a status of at least one of said plurality of radio resources, said at least one of said plurality of radio resources including said at least one reserved radio resource, said generating circuitiy being further configured to generate a priority value for said coordination information; wherein said generating circuitry is configured to generate said priority value in dependence upon at least one of said corresponding at least one priority values determined by said determining circuitry; and transmitting circuitry configured to transmit said coordination information and said priority value to at least one other apparatus.

In some example embodiments, in response to said determining circuitiy determining a single reserved radio resource, said generating circuitry is configured to set said priority value for said coordination information to said corresponding priority value associated with said single reserved radio resource.

In some example embodiments, in response to said determining circuitry determining multiple reserved radio resources, said generating circuitry is configured to determine a highest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information in dependence upon said highest priority value.

In some example embodiments, in response to said determining circuitry determining multiple reserved radio resources, said generating circuitry is configured to determine a lowest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information in dependence upon said lowest priority value.

In some example embodiments, in response to said determining circuitry determining multiple reserved radio resources, said generating circuitry is configured to determine said priority value for said coordination information as a function of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information to reflect said function of said corresponding priority values.

In some example embodiments, in response to said determining circuitry determining multiple reserved radio resources, said generating circuitry is configured to indicate multiple priority values to reflect corresponding priority values associated with said multiple reserved radio resources.

In some example embodiments, in response to said determining circuitry determining said apparatus is to transmit in a time slot, said generating circuitry is configured to generate an indication of said time slot as a non-preferred radio resource and to set said priority value for said coordination information to a priority value associated with data to be transmitted by said apparatus in said time slot.

In some example embodiments, said generating circuitry is further configured to determine a measure of radio channel congestion and to adjust said priority value in dependence upon said measure of radio channel congestion.

In some example embodiments, said determining circuitry is configured to determine a signal strength associated with a transmission indicating said at least one reserved radio resource and to adjust said priority value for said coordination information in dependence upon said signal strength .

Further particular and preferred aspects are set out in the accompanying independent and dependent claims. Features of the dependent claims maybe combined with features of the independent claims as appropriate, and in combinations other than those explicitly set out in the claims. Where an apparatus feature is described as being operable to provide a function, it will be appreciated that this includes an apparatus feature which provides that function or which is adapted or configured to provide that function.

BRIEF DESCRIPTION

Some example embodiments will now be described with reference to the accompanying drawings in which:

Fig.i schematically illustrates an example of direct transmissions between status, the transmission of coordination information regarding reserved resources; and Fig. 2 schematically illustrates a flow diagram illustrating steps in a method according to an embodiment;

Fig. 3 schematically illustrates a further method according to an embodiment; and Fig. 4 schematically illustrates an apparatus according to an embodiment.

DETAILED DESCRIPTION

Before discussing the example embodiments in any more detail, first an overview will be provided.

This application is related to Sidelink (SL) Inter- UE Coordination (IUC) to enhance resource allocation for direct transmission between UEs and involves the transmission of Inter-UE Coordination information (IUC-I) between the UEs. The priority value for such IUC-I may not always be (pre)configured and embodiments look at generating a priority value where this is the case.

This application proposes a procedure for a user equipment UE-A that is scheduled to receive a transmission from a UE-B for generating an IUC-I indicative of preferred and/or non-preferred resources for this transmission along with a priority value for this IUC-I, this priority value being based on the priority value(s) associated with and used to determine the preferred or non-preferred resources conveyed in the IUC-I message. UE-B takes account of the information in the IUC-I message in the resource selection for its own transmission.

In this regard a resource may be considered to be preferred or non-preferred based on the strength of the signal and a priority value indicated in a sidelink information field for that apparatus. Thus, a radio resource that is to be used for a transmission may be considered to be non-preferred where the RSRP (reference signal to received power) is higher than a threshold value, the threshold value being based on an indicated priority. Or where the UE is a destination for a transport block then the radio resource may be considered to be non-preferred where the RSRP measurement is lower than a threshold value based on an indicated priority of the transmission. Resources may also be considered to be non-preferred for a UE that is to be a destination for a transmission (transport block) where they are in a time slot in which the UE does not expect to perform SL reception due to half duplex operation.

The radio resources may comprise frequency sub-channels and/or time slots for the transmission of data and information. The status of the radio resource may comprise whether it is a preferred or non-preferred resource and the coordination information may indicate both the reserved resource and its status. The means for determining whether the resources were reserved and their priority may do so by receiving coordination information in a transmission from another apparatus or by sensing transmission such as sidelink control information transmissions, broadcast by other apparatuses.

When generating the IUC-I a priority value is also generated and embodiments seek to base the priority value on the priority value(s) of the radio resource(s) that they are trying to protect. In this regard the priority of the IUC-I transmission may be seen as inheriting the priority of the link (radio resource) that it seeks to protect. So a higher priority link is provided with higher priority protection than a lower priority link.

The priority value (prio_RX) of a received SCI (sidelink control information), which is currently used by UE-A to determine the RSRP threshold (Th) for determination of preferred or non-preferred resources, can also be used as the priority value of the corresponding IUC-I transmission conveying the determined preferred or nonpreferred resources.

If the preferred or non-preferred resource set is determined from different SCIs (sidelink control information) with different priority values (prio_RX), then one of the following rules (or a combination thereof) can be applied to determine the priority value of the corresponding IUC-I transmission: the highest priority value among all the decoded SCIs; or the lowest priority value among all the decoded SCIs; or some function of all the decoded SCIs such as the average of the priority values; or the priority value of the decoded SCI with the highest associated RSRP; or the priority value of the decoded SCI with the lowest associated RSRP; or the priority value selected based on the priority value with the highest number of decoded SCIs, that is the mode of the priority values rather than their average value.

The priority value of UE-A’s (the receiving UE) SL transmissions may be used to determine the priority value of the corresponding IUC-I transmission, e.g., when the IUC-I transmission conveys preferred/non-preferred resources determined due to halfduplex operation.

The expected priority value of UE-B’s expected SL transmissions may be used to determine the priority value of the corresponding IUC-I transmission when the IUC-I transmission conveys preferred/non-preferred resources determined due to halfduplex operation.

The priority value of IUC-I maybe adapted (e.g., increased or decreased) based on a CBR (channel busy ratio) measurement, the time the channel is measured as being busy compared to the total measured time. For example, for higher measured CBR, the priority value of the IUC-I (determined by the above conditions) can be decreased (i.e., given higher priority). While for lower measured CBR, the priority value of the IUC-I is the one determined by the above conditions.

The priority value of IUC-I maybe adapted (e.g., increased or decreased) based on SL RSRP measurements. E.g. when a resource is non-preferred because UE-A is destination UE of another transmission whose RSRP measurement is smaller than a (pre)configured RSRP threshold then the priority may be adjusted based on the difference between the measured RSRP and the threshold.

Fig. i schematically illustrates a possible situation a TX (B5) might face when selecting a resource among candidate resources (ri,r2,r3,r4) for transmission to a RX (A5).

In this example a plurality of user equipment Al, A2, A3, A4, A5 are receiving transmissions from a plurality of apparatuses Bi, B2, B3, B4, B5 that are transmitting signals.

Resource ri is booked by Bi (TX) for transmission to Al (RX) with priority pi. Resource r2 is booked by B2 (TX) for transmission to A2 (RX) with priority p2. Resource r3 is booked by B3 (TX) for transmission to A3 (RX) with priority p3. Resource r4 is booked by B4 (TX) for transmission to A4 (RX) with priority p4.

The TX (B5) receives the following IUC information:

From A5: resources (ri,r4) are non-preferred for Bs’s transmission to A5, as reception at A5 would be compromised by interference from BI,B4.

From A2: resource (r2) is non-preferred for Bs’s transmission, as Bs’s transmission would cause interference to A2’s reception of B2’s transmission.

From A3: resource (r3) is non-preferred for Bs’s transmission, as Bs’s transmission would cause interference to A3’s reception of Bs’s transmission.

In short, among the candidate resources (ri,r2,r3,r4), all of them are non-preferred (according to IUC information received at B5).

In this situation, assuming the IUC transmissions were not triggered by an explicit request from B5 and assuming that IUC transmission priority has not been preconfigured in the resource pool, it is proposed that the IUC transmissions “inherit” the priority of the respective sidelink transmissions they’re trying to protect.

In this example: the IUC transmission from A2 is transmitted with priority p2, corresponding to the priority of link (B2,A2). the IUC transmission from A3 is transmitted with priority p3, corresponding to the priority of link (B3,A3).

A5 receives information regarding multiple reserved resources (ri, r4) and thus, selects a priority based on one of or a function of the priority values of these multiple reserved resources. In this case the IUC transmission from A5 is transmitted with priority p5, which (according to an embodiment) may be the highest priority among pi and p4, corresponding to the priorities of link (B1,A1) and (B4,A4), respectively.

In this way, B5 can determine which candidate resource (ri,r2,r3,r4) is non-preferred (needs to be protected/excluded) with what priority. For example, if p2 has lowest priority among all, then B5 may select r2 for its transmission to A5.

In this embodiment, apparatus A5 selected the highest priority as the priority value for the IUC-I transmission. In other embodiments, it may select a function of the two priorities thus, it might select an average of priority Pi and P4 or it may indeed select the lowest priority in some cases. In some example embodiments A5 may transmit both priorities, this would require additional signalling.

In some cases the priority value that is determined based on the priority values of the reserved resources maybe adjusted based on signal strength. For example looking at the link between B2 and A2, there is a reserved resource r2 with priority P2 and this priority may be used for the IUC-I communication. However, if it is determined from the RSRP that the signal from B2 to A2 is weak then the priority value may be increased to protect the link, while if the signal from B2 to A2 is stronger then the priority value may not need to be increased, indeed in some cases it may be reduced.

Alternatively and/or additionally the priority value maybe adapted, based on a channel busy ratio measurement. For example the higher the measured CBR, then the higher priority required for the coordination information and thus, the priority value can be reduced. While for lower measured CBR’s the priority value of the IUC-I is not altered and may even be increased.

Fig. 2 shows a flow diagram illustrating steps in a method according to an embodiment. In a first step S10 at least one radio resource that is booked or reserved is determined along with an associated priority value. At step S20 coordination information indicative of the status of the at least one reserved resource is generated.

A priority value for this coordination information then needs to be generated and the following steps may be performed to do this. At D15 it is determined if there are multiple reserved resources. If there are not then at step S40 the priority value for the coordination information maybe set to the priority value of the reserved resource. This maybe the end of the procedure for generating a priority value, but in some embodiments the priority value maybe adjusted depending on sensed conditions. So in step D17 it may be determined whether the signal strength of the apparatus reserving the resource is low i.e. below a threshold. If it is low, the priority may be increased by decreasing the priority value at step S42.

If there are multiple reserved resources then at step S60 the priority value may be set to a function of the priority values of the multiple reserved resources. In this regard the function may be an average function, it may be a weighted average function, or it may be a function indicating select the highest or the lowest priority value. The choice of function may depend on the particular requirements of the transmitting and receiving user equipment. The priority values that the function is applied to, may be the priority values of the reserved resource or it may be these values adjusted in dependence upon the RSRP of the apparatus that is reserving the resource.

The priority value set at step S6o may be the one that is used, but in some example embodiments further steps are performed. For example a further step D25 may be performed where it is determined whether the radio channel congestion is above a threshold and if it is the priority value that has been set for the coordination information may be decreased at step S50. This step may also be performed for the priority value that has been set where there is only one reserved resource.

The coordination information and associated priority value are then transmitted to the further UE, UE-B or B5 of Fig. 1 at step S70.

Fig. 3 shows further steps that may be performed in a method according to an embodiment, where the determined reserved radio resource is a time slot in which the apparatus is to transmit a signal and thus, will not be able to receive due to half duplex operation. In this example at step S110 it is determined that there is a reserved resource in the form of a time slot and at step 120 the expected or known priority of the data that it is to be transmitted in this time slot is determined and at step S130 the coordination information is generated, this indicates that the time slot is a reserved resource. A priority value is generated for the coordination information at step S140 and this is based on the priority of the data to be transmitted. S130 and S140 may be performed in any order. At step S150 the coordination information and associated priority value are transmitted to user equipment UE-B or B5 of Fig. 1.

Fig.4 schematically shows an apparatus 10 according to an embodiment. Apparatus 10 is a user equipment and comprises an antenna 20 for transmitting and receiving direct communications with other apparatus. It also has determining means 30 for determining at least one radio resource that is reserved by an apparatus. The apparatus may be itself (in the form perhaps of a time slot during which it is to transmit) or it may be another apparatus in the vicinity, that is close enough so that the use of the same resource may lead to interference. The determining means 30 may determine the reserve resource in a number of ways including by receiving a coordination signal transmitted to it, or by sensing signals broadcast by other apparatuses or by determining that it is to transmit in a time slot. The determining means may also determine a priority value of the reserved resource(s) in the same way. The apparatus also comprises a generating means 40 for generating coordination information for transmitting to a further apparatus, the coordination information being indicative of the reserved resources that have been determined by the determining means. The generating means 40 may also generate a priority value for the coordination information. This priority value may be based on the priority values determined for the reserved resource(s). There may also be adjusting means 50 for adjusting the priority value that has been generated, the adjusting means may adjust the value in dependence upon one of a signal strength of a signal from an apparatus that has reserved a resource, or a congestion value indicative of a congestion of a channel for transmission of the coordination information.

In summary when UE-A determines a non-preferred resource set to be included in its IUC-I message, the following standardized conditions maybe used. For each of the conditions, the priority value of UE-A’s IUC-I transmission conveying the nonpreferred resources is determined, according to the following details.

Condition 1-B-1 (Option 1)

A UE-A considers as non-preferred resource(s): resource(s) indicated by a received SCI, where: the RSRP measurement performed, for the received SCI signal , is higher than Th(prio_RX ) where prio_RX is the value of the priority field in the received SCI signal. If non-preferred resources are identified according to Condition 1-B-1 (Option 1), the corresponding priority value prio_RX is linked to the non-preferred resources identified by this condition.

Condition 1-B-1 (Option 2)

A UE-A considers as non-preferred resource(s): resource(s) indicated by a received SCI, satisfying: the UE is a destination UE of a TB associated with the received SCI and the RSRP measurement performed for the received SCI signal, is lower than Th'(prio_RX ) where prio_RX is the value of the priority field in the received SCI signal.

If non-preferred resources are identified according to Condition 1-B-1 (Option 2), the corresponding priority value prio_RX is linked to the non-preferred resources identified by this condition.

Condition 1-B-2 A UE considers as non-preferred resource(s):

[slot(s)] in which the UE does not expect to perform SL reception due to half duplex operation, if the UE is a destination UE of a TB for whose transmission the nonpreferred resource set is being determined.

If non-preferred resources are identified according to Condition 1-B-2, the priority value of UE-A’s SL data to be transmitted is linked to the non-preferred resources identified by this condition. Alternatively, the priority value of the “TB for whose transmission the non-preferred resource set is being determined”, if known or predictable by UE-A, is linked to the non-preferred resources identified by this condition,

Based on the priority value(s) that are linked to the identified non-preferred resources, UE-A may determine the final priority value of the IUC-I transmission. For instance, the highest/lowest priority value (meaning the lowest/highest priority) maybe used as the final priority value of the IUC-I transmission. Alternatively, the average priority value from all priority values may be used as the final priority value of the IUC-I transmission. Different weights may be applied to priority value(s) linked to nonpreferred resources identified by different conditions, when the average value is calculated. The applied weight may be (pre)configured to UE-A or may be determined based on the number of identified non-preferred resources. In addition, the priority value or the weight of different priority values used to calculate the final priority value maybe adapted according to a CBR measurement and/or SL RSRP measurement. For instance, different CBR/SL RSRP ranges may be (pre)configured and the final priority value may be increased or decreased if the CBR/SL RSRP measurement result is within one of the (pre)configured CBR/SL RSRP ranges.

A person of skill in the art would readily recognize that steps of various abovedescribed methods can be performed by programmed computers. Herein, some embodiments are also intended to cover program storage devices, e.g., digital data storage media, which are machine or computer readable and encode machineexecutable or computer-executable programs of instructions, wherein said instructions perform some or all of the steps of said above-described methods. The program storage devices maybe, e.g., digital memories, magnetic storage media such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media. The embodiments are also intended to cover computers programmed to perform said steps of the above-described methods. As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable):

(i) a combination of analog and/or digital hardware circuit(s) with software/firmware and

(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitiy also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not. Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. An apparatus comprising means for determining at least one radio resource of a plurality of radio resources that is reserved for sidelink transmission by at least one of a plurality of apparatuses and a corresponding at least one priority value associated with said at least one reserved radio resource; means for generating coordination information indicative of a status of at least one of said plurality of radio resources, said at least one of said plurality of radio resources including said at least one reserved radio resource, and for generating a priority value for said coordination information; wherein said means for generating is configured to generate said priority value in dependence upon at least one of said corresponding at least one priority values determined; and means for transmitting said coordination information and said priority value to at least one other apparatus.

2. An apparatus according to claim 1, wherein in response to said means for determining determining a single reserved radio resource, said means for generating is configured to set said priority value for said coordination information to said corresponding priority value associated with said single reserved radio resource.

3. An apparatus according to claim 1 or 2, wherein in response to said means for determining determining multiple reserved radio resources, said means for generating is configured to determine a highest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information in dependence upon said highest priority value.

4. An apparatus according to claim 1 or 2, wherein in response to said means for determining determining multiple reserved radio resources, said means for generating is configured to determine a lowest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information in dependence upon said lowest priority value.

5. An apparatus according to claim 1 or 2, wherein in response to said means for determining determining multiple reserved radio resources, said means for generating is configured to determine said priority value for said coordination information as a function of corresponding priority values associated with said multiple reserved radio resources and to set said priority value for said coordination information to reflect said function of said corresponding priority values.

6. An apparatus according to any preceding claim, wherein in response to said means for determining determining multiple reserved radio resources, said means for generating is configured to indicate multiple priority values to reflect corresponding priority values associated with said multiple reserved radio resources.

7. An apparatus according to any preceding claim, wherein in response to said means for determining determining said apparatus is to transmit in a time slot, said means for generating is configured to generate an indication of said time slot as a nonpreferred radio resource and to set said priority value for said coordination information to a priority value associated with data to be transmitted by said apparatus in said time slot.

8. An apparatus according to any preceding claim, wherein said means for generating is further configured to determine a measure of radio channel congestion and to adjust said priority value in dependence upon said measure of radio channel congestion.

9. An apparatus according to any preceding claim, wherein said means for determining is configured to determine a signal strength associated with a transmission indicating said at least one reserved radio resource and to adjust said priority value for said coordination information in dependence upon said signal strength .

10. An apparatus according to any preceding claim wherein the means comprise: at least one processor; and at least one memoiy including computer program code, the at least one memory and computer program code being configured to, with the at least one processor, cause the performance of the apparatus. n. A method comprising determining at least one radio resource of a plurality of radio resources that is reserved for sidelink transmission by at least one of a plurality of apparatuses and a corresponding at least one priority value associated with said at least one reserved radio resource; generating coordination information indicative of a status of at least one of said plurality of radio resources, said at least one of said plurality of radio resources including said at least one reserved radio resource; generating a priority value for said coordination information in dependence upon at least one of said corresponding at least one priority value determined; and transmitting said coordination information and said priority value to at least one other apparatus.

12. A method according to claim 11, wherein in response to determining a single reserved radio resource, generating said priority value by setting said priority value for said coordination information to said corresponding priority value associated with said single reserved radio resource.

13. A method according to claim 11 or 12, wherein in response to determining multiple reserved radio resources, determining a highest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and sets said priority value for said coordination information in dependence upon said highest priority value.

14. A method according to claim 11 or 12, wherein in response to determining multiple reserved radio resources, determining a lowest priority value among said plurality of corresponding priority values associated with said multiple reserved radio resources and sets said priority value for said coordination information in dependence upon said lowest priority value.

15. A method according to claim 11 or 12, wherein in response to determining multiple reserved radio resources, determining said priority value for said coordination information as a function of corresponding priority values associated with said multiple reserved radio resources and sets said priority value for said coordination information to reflect said function of said corresponding priority values.

16. A method according to any one of claims 11 to 15, wherein in response to determining multiple reserved radio resources indicating multiple priority values within said coordination information to reflect corresponding priority values associated with said multiple reserved radio resources. 17- A method according to any one of claims 11 to 16, wherein in response to determining that said apparatus is to transmit in a time slot, generating an indication of said time slot as a non-preferred radio resource and sets said priority value for said coordination information to a priority value associated with data to be transmitted by said apparatus in said time slot.

18. A method according to any one of claims 11 to 17, said method further comprising determining a measure of radio channel congestion and adjusting said priority value in dependence upon said measure of radio channel congestion.

19. A method according to any one of claims 11 to 18, wherein said step of determining determines a signal strength associated with a transmission indicating said at least one reserved radio resource and adjusts said priority value for said coordination information in dependence upon said signal strength .

20. An apparatus configured to perform a method according to any one of claims 11 to 19.

21. A computer program which when executed by a processor on an apparatus is configured to control said apparatus to perform a method according to any one of claims 11 to 19.