Patent Description:
In an Evolved Universal Mobile Telecommunications System Terrestrial Radio Access Network (E-UTRAN), an evolved node B (eNB) may be responsible for allocating wireless channel resources to accommodate device-to-device (D2D) data transmissions of any D2D-capable user equipment (D2D UEs) that wish to perform such transmissions. An eNB can notify a D2D UE of resources allocated for D2D data transmissions by sending a scheduling grant to the D2D UE. Requiring the eNB to send a separate scheduling grant for each D2D data transmission may impose excessive, undesirable signaling overhead. In an out-of-coverage scenario in which a transmitting D2D UE does not have connectivity with an eNB, the transmitting D2D UE may autonomously select the wireless channel resources to be used to accommodate its D2D data transmission(s) to a recipient D2D UE. Regardless of whether an eNB allocates the resources for the transmitting D2D UE or the transmitting D2D UE autonomously selects those resources, the transmitting D2D UE needs to send control information to notify the recipient D2D UE of the wireless channel resources via which it will perform its D2D data transmission(s) to the recipient D2D UE. If the transmitting D2D UE is required to send control information identifying the specific resources to be used for each respective D2D data transmission, this may also constitute a cause of excessive signaling overhead. In order to reduce the signaling overhead associated with resource allocation for D2D transmissions, it may be desirable that eNBs and D2D UEs be configured to communicate D2D resource allocation information in a compact, non-message-specific format.

<CIT> discloses a method for configuring an uplink and downlink splitting pattern for D2D communication under a cellular network.

<CIT> discloses a wireless network, such as an Long-Term Evolution, LTE, network configured to receive an identifier associated with resource configurations in a wireless network.

The invention is defined by a method of performing device-to-device, D2D, data transmission using resources of an identified set of subframes. The method comprises identifying a device-to-device transmission pattern, DTP, index based on received D2D control information received via a physical downlink control channel, PDCCH, wherein the DTP specifies a time interval during which D2D transmissions are permitted; determining a DTP bitmap corresponding to the DTP index; identifying a set of subframes comprising D2D transmission resources based on the DTP bitmap; and performing D2D data transmission using resources of the identified set of subframes. Furthermore, an apparatus, a system, and a computer-readable storage medium are defined.

Various embodiments may be generally directed to resource allocation techniques for D2D communications. In one embodiment, for example, user equipment may comprise one or more radio frequency (RF) transceivers, one or more RF antennas, and logic, at least a portion of which is in hardware, the logic to receive a D2D control information (D2DCI) message comprising D2D data transmission pattern (DTP) information, identify a set of D2D transmission resources based on the DTP information, and send one or more D2D data messages using the set of D2D transmission resources. Other embodiments are described and claimed.

Various embodiments may comprise one or more elements. An element may comprise any structure arranged to perform certain operations. Each element may be implemented as hardware, software, or any combination thereof, as desired for a given set of design parameters or performance constraints. Although an embodiment may be described with a limited number of elements in a certain topology by way of example, the embodiment may include more or less elements in alternate topologies as desired for a given implementation. It is worthy to note that any reference to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrases "in one embodiment," "in some embodiments," and "in various embodiments" in various places in the specification are not necessarily all referring to the same embodiment.

The techniques disclosed herein may involve transmission of data over one or more wireless connections using one or more wireless mobile broadband technologies. For example, various embodiments may involve transmissions over one or more wireless connections according to one or more 3rd Generation Partnership Project (3GPP), 3GPP Long Term Evolution (LTE), and/or 3GPP LTE-Advanced (LTE-A) technologies and/or standards, including their predecessors, revisions, progeny, and/or variants. Various embodiments may additionally or alternatively involve transmissions according to one or more Global System for Mobile Communications (GSM)/Enhanced Data Rates for GSM Evolution (EDGE), Universal Mobile Telecommunications System (UMTS)/High Speed Packet Access (HSPA), and/or GSM with General Packet Radio Service (GPRS) system (GSM/GPRS) technologies and/or standards, including their predecessors, revisions, progeny, and/or variants.

Examples of wireless mobile broadband technologies and/or standards may also include, without limitation, any of the Institute of Electrical and Electronics Engineers (IEEE) <NUM> wireless broadband standards such as IEEE <NUM> and/or <NUM>. 16p, International Mobile Telecommunications Advanced (IMT-ADV), Worldwide Interoperability for Microwave Access (WiMAX) and/or WiMAX II, Code Division Multiple Access (CDMA) <NUM> (e.g., CDMA2000 1xRTT, CDMA2000 EV-DO, CDMA EV-DV, and so forth), High Performance Radio Metropolitan Area Network (HIPERMAN), Wireless Broadband (WiBro), High Speed Downlink Packet Access (HSDPA), High Speed Orthogonal Frequency-Division Multiplexing (OFDM) Packet Access (HSOPA), High-Speed Uplink Packet Access (HSUPA) technologies and/or standards, including their predecessors, revisions, progeny, and/or variants.

Some embodiments may additionally or alternatively involve wireless communications according to other wireless communications technologies and/or standards. Examples of other wireless communications technologies and/or standards that may be used in various embodiments may include, without limitation, other IEEE wireless communication standards such as the IEEE <NUM>, IEEE <NUM>1a, IEEE <NUM>. 11b, IEEE <NUM>, IEEE <NUM>. 11n, IEEE <NUM>. 11u, IEEE <NUM>. 11ac, IEEE <NUM>. 11ad, IEEE <NUM>. 11af, and/or IEEE <NUM>. 11ah standards, High-Efficiency Wi-Fi standards developed by the IEEE <NUM> High Efficiency WLAN (HEW) Study Group, Wi-Fi Alliance (WFA) wireless communication standards such as Wi-Fi, Wi-Fi Direct, Wi-Fi Direct Services, Wireless Gigabit (WiGig), WiGig Display Extension (WDE), WiGig Bus Extension (WBE), WiGig Serial Extension (WSE) standards and/or standards developed by the WFA Neighbor Awareness Networking (NAN) Task Group, machine-type communications (MTC) standards such as those embodied in 3GPP Technical Report (TR) <NUM>, 3GPP Technical Specification (TS) <NUM>, and/or 3GPP TS <NUM>, and/or near-field communication (NFC) standards such as standards developed by the NFC Forum, including any predecessors, revisions, progeny, and/or variants of any of the above. The embodiments are not limited to these examples.

In addition to transmission over one or more wireless connections, the techniques disclosed herein may involve transmission of content over one or more wired connections through one or more wired communications media. Examples of wired communications media may include a wire, cable, metal leads, printed circuit board (PCB), backplane, switch fabric, semiconductor material, twisted-pair wire, co-axial cable, fiber optics, and so forth.

<FIG> illustrates an example of an operating environment <NUM> in which the disclosed resource allocation techniques for D2D communications may be implemented in various embodiments. As shown in <FIG>, an eNB <NUM> serves a cell <NUM>, and generally provides wireless connectivity to UEs <NUM> and <NUM>. In conjunction with providing such wireless connectivity, eNB <NUM> may perform operations such as managing radio resource control (RRC) states of UEs <NUM> and/or <NUM>, allocating wireless channel resources for communications on the part of UEs <NUM> and/or <NUM>, notifying UEs <NUM> and/or <NUM> of such allocated resources, and sending data to and/or receiving data from UEs <NUM> and/or <NUM>. The way in which eNB <NUM> allocates wireless channel resources for communications on the part of UEs <NUM> and/or <NUM> may depend in part on the duplexing mode being used. In some embodiments, eNB <NUM> may implement frequency division duplexing (FDD), according to which it may allocate resources of one or more uplink (UL) channels to accommodate transmissions by UEs <NUM> and/or <NUM>, and may allocate resources of one or more downlink (DL) channels to accommodate transmissions to UEs <NUM> and/or <NUM>. In various other embodiments, eNB <NUM> may implement time division duplexing (TDD). In some embodiments in which TDD is implemented, eNB <NUM> may be operative to select and report a TDD configuration to UEs <NUM> and <NUM>, and the TDD configuration may specify subframes or other time intervals to be used for UL communications and subframes or other time intervals to be used for DL communications. In such embodiments, eNB <NUM> may then be operative to allocate resources of one or more UL subframes or other time intervals to accommodate transmissions by UE <NUM> and/or UE <NUM>.

<FIG> illustrates an example of an operating environment <NUM> in which the disclosed resource allocation techniques for D2D communications may be implemented in various embodiments. In operating environment <NUM>, UEs <NUM> and <NUM> of <FIG> are configured with D2D communication capabilities, and UE <NUM> has data for D2D transmission to UE <NUM>. eNB <NUM>, which is responsible for allocated wireless channel resources to accommodate D2D data transmissions, may send a D2D scheduling grant <NUM> to notify UE <NUM> of wireless channel resources that it may use for D2D data transmission. In some embodiments, D2D scheduling grant <NUM> may comprise information within a control message that eNB <NUM> sends to UE <NUM>, such as an RRC control message. UE <NUM> may use information in D2D scheduling grant <NUM> to identify wireless channel resources for use in D2D transmission of data to UE <NUM>. Prior to performing its D2D data transmission(s) to UE <NUM>, UE <NUM> may send control information <NUM> to notify UE <NUM> of the wireless channel resources allocated for its D2D data transmission(s). UE <NUM> may then perform D2D transmission of data <NUM> to UE <NUM>, and UE <NUM> may receive the data <NUM> via some or all of the wireless channel resources allocated for D2D data transmission(s) of UE <NUM>.

In various embodiments, UE <NUM> may have multiple D2D messages to transmit to UE <NUM>, and/or may frequently generate D2D messages for transmission to UE <NUM>. Requiring that D2D scheduling grant <NUM> specifically identify distinct respective resource sets for each D2D message - or requiring that eNB <NUM> send separate D2D scheduling grants <NUM> for each D2D message that UE <NUM> has to send - may result in an excessive overall overhead associated with notifying UE <NUM> of the resources that it may use. As such, it may be desirable that D2D scheduling grant <NUM> identify resources that may be used to accommodate multiple D2D messages, but that it not be required to identify such resources in a D2D message-specific manner. It may also be desirable that D2D scheduling grant <NUM> be formatted such that it can convey such information while comprising a relatively compact structure. In some embodiments, the format for the control information <NUM> that UE <NUM> sends to UE <NUM> may mirror that of the D2D scheduling grant <NUM> that eNB <NUM> sends to UE <NUM>. In such embodiments, the use of a compact, non-message-specific format for D2D scheduling grant <NUM> may also beneficially reduce overhead associated with transmissions of control information <NUM> by transmitting D2D UEs, even with respect to control information <NUM> sent by out-of-coverage transmitting D2D UEs.

Disclosed herein are resource allocation techniques for D2D communications. According to some disclosed techniques, an eNB may be configured to select a D2D data transmission pattern (DTP) that generally specifies subframes or other time intervals during which a D2D UE is permitted to perform D2D transmissions. In various embodiments, the eNB may be configured to notify the D2D UE of the selected DTP by sending a D2D control information (D2DCI) message that comprises information identifying the selected DTP. In some embodiments, the eNB may indicate the selected DTP simply by including a DTP index in the D2DCI message. In various embodiments, the D2D UE may be operative to transmit multiple D2D messages using respective sets of available resources specified by the same DTP index.

<FIG> illustrates an example of an operating environment <NUM> in which the disclosed resource allocation techniques for D2D communications may be implemented in some embodiments. In operating environment <NUM>, eNB <NUM> sends D2D control information <NUM> to UE <NUM>. In various embodiments, D2D control information <NUM> may be comprised within one or more information elements (IEs) of a control message, such as an RRC message. In some embodiments, eNB <NUM> may periodically transmit D2D control information <NUM> to UE <NUM>. In various embodiments, D2D control information <NUM> may generally comprise parameters and/or other information to be applied by UE <NUM> in conjunction with D2D communications. In some embodiments, eNB <NUM> may be operative to select a DTP for UE <NUM>. In the claimed embodiments, the DTP specifies subframes or other time intervals during which UE <NUM> is permitted to perform D2D transmissions. In some embodiments, eNB <NUM> may be operative to select the DTP for UE <NUM> from among a set of defined DTPs.

<FIG> illustrates an example of a DTP set <NUM> such as may be representative of a DTP set from among which eNB <NUM> may select a DTP in various embodiments. In the example of <FIG>, DTP set <NUM> comprises DTPs <NUM>, <NUM>, <NUM>, and <NUM>. The subframes that are shaded in each DTP represent the subframes that are allocated for D2D transmissions according to that DTP. With respect to any particular DTP, the term "pattern duration" shall be employed herein to denote the length of that DTP with respect to some time unit or unit that is a proxy for time. In this example, each of DTPs <NUM>, <NUM>, <NUM>, and <NUM> comprises a pattern duration of forty subframes, or four frames. With respect to any particular DTP, the term "D2D allocation ratio" shall be employed herein to denote the ratio between the amount of time units and/or wireless channel resources that the DTP allocates for D2D transmissions and the amount of time units and/or wireless channel resources that the DTP does not allocate for D2D transmissions over the course of the pattern duration. In this example, each of DTPs <NUM>, <NUM>, <NUM>, and <NUM> allocates ten subframes for D2D transmissions and does not allocate the remaining thirty subframes for D2D transmissions. As such, each of DTPs <NUM>, <NUM>, <NUM>, and <NUM> exhibits a D2D allocation ratio of <NUM>/<NUM>.

In the example of <FIG>, although DTPs <NUM>, <NUM>, <NUM>, and <NUM> feature the same pattern durations and D2D allocation ratios, they are orthogonal in time with respect to their D2D allocations. During any particular subframe, only one of these four DTPs will indicate that D2D transmissions are permitted. In some embodiments, an eNB that selects from among a DTP set may consider such orthogonality when selecting the DTP. For example, eNB <NUM> of <FIG> may select a DTP for UE <NUM> that is orthogonal in time to a DTP that it has selected for another UE. It is worthy of note that - as reflected by the presence of the letter "U" in each subframe for each DTP therein - DTP set <NUM> is representative of an FDD configuration, according to which UL transmissions may be performed in every subframe. However, the embodiments are not limited in this context, and the techniques herein may also be implemented in conjunction with FDD configurations.

<FIG> illustrates an example of a DTP set <NUM> such as may be representative of a DTP set from among which eNB <NUM> may select a DTP in various embodiments. In the example of <FIG>, DTP set <NUM> comprises DTPs <NUM>, <NUM>, <NUM>, and <NUM>. Like DTPs <NUM>, <NUM>, <NUM>, and <NUM> of <FIG>, DTPs <NUM>, <NUM>, <NUM>, and <NUM> each comprise pattern durations of forty subframes. However, in this example, each of DTPs <NUM>, <NUM>, <NUM>, and <NUM> features a different D2D allocation ratio. DTP <NUM> features a D2D allocation ratio of <NUM>/<NUM> (or <NUM>/<NUM>), DTP <NUM> features a D2D allocation ratio of <NUM>/<NUM> (or <NUM>/<NUM>), DTP <NUM> features a D2D allocation ratio of <NUM>/<NUM> (or <NUM>/<NUM>), and DTP <NUM> features a D2D allocation ratio of <NUM>/<NUM> (or <NUM>). Some of DTPs <NUM>, <NUM>, <NUM>, and <NUM> are orthogonal in time to each other, while others are not. For example, DTPs <NUM>, <NUM>, and <NUM> are mutually orthogonal in time, and DTP <NUM> is orthogonal in time to DTP <NUM>, but DTP <NUM> is not orthogonal in time to either DTP <NUM> or DTP <NUM>.

In some embodiments, an eNB that selects from among a DTP set such as DTP set <NUM> may consider a desired D2D data rate for a UE to which the selected DTP is to apply. In various embodiments, for example, the eNB may select a DTP exhibiting a D2D allocation ratio that is appropriate for the desired D2D data rate. For a D2D UE that requires a relatively high D2D data rate, the eNB may select a DTP featuring a relatively high D2D allocation ratio, such as DTP <NUM>. For a D2D UE that does not require more than a minimal D2D data rate, the eNB may select a DTP featuring a relatively low D2D allocation ratio, such as DTP <NUM>. In some embodiments, D2D data rate considerations may be performed in concert with time orthogonality considerations. In an example, an eNB that has selected DTP <NUM> for a first D2D UE may also need select a DTP for a second D2D UE for which the desired D2D data rate can be achieved via DTP <NUM>. Despite the fact that DTP <NUM> features a sufficient D2D allocation ratio to meet the needs of the second D2D UE, the eNB may select DTP <NUM> for the second D2D UE, because DTP <NUM> is orthogonal in time to DTP <NUM> while DTP <NUM> is not. The embodiments are not limited to this example.

It is to be understood that the embodiments are not limited to the numbers of DTPs, pattern durations or underlying time units, D2D allocation ratios, or other DTP set characteristics depicted in <FIG> and <FIG>. In various embodiments, a DTP set may comprise a lesser or greater number of different DTPs, which may or may not be of the same pattern duration or feature the same D2D allocation ratio, and may or may not be defined at a subframe level of granularity. It is again to be appreciated that the disclosed techniques may be implemented in conjunction with TDD configurations, despite the fact that the examples of <FIG> and <FIG> are representative of FDD configurations.

Returning to <FIG>, in some embodiments, eNB <NUM> may be operative to select the DTP for UE <NUM> based on a desired D2D data rate for UE <NUM>. In various embodiments, eNB <NUM> may be operative to select a particular DTP for UE <NUM> based on a determination that the DTP is orthogonal in time to a DTP that it has selected for another D2D UE. In some embodiments, eNB <NUM> may be operative to report the selected DTP to UE <NUM> by sending D2D control information <NUM> comprising DTP information <NUM> that specifies the selected DTP. In various embodiments, eNB <NUM> may select the DTP from among a defined DTP set, and a unique respective DTP index may be associated with each DTP in the set. In some embodiments, each DTP index may comprise a sequence of bits. In an example, the DTP indices for DTPs <NUM>, <NUM>, <NUM>, and <NUM> of <FIG> may be '<NUM>','<NUM>','<NUM>', and '<NUM>', respectively. In various embodiments, eNB <NUM> may be operative to select a DTP for UE <NUM> and identify a DTP index <NUM> as the DTP index that corresponds to the selected DTP. In some embodiments, eNB <NUM> may be operative to report the selected DTP to UE <NUM> by sending D2D control information <NUM> comprising DTP information <NUM> that contains the DTP index <NUM>. In various embodiments, eNB <NUM> may be operative to send D2D control information <NUM> to UE <NUM> over a physical downlink control channel (PDCCH).

In the claimed embodiments, UE <NUM> is operative to receive D2D control information <NUM> and identify a set of D2D transmission resources based on DTP information <NUM>. In the claimed embodiments, UE <NUM> identifies the selected DTP based on DTP information <NUM> and identify the set of D2D transmission resources based on the selected DTP. In the claimed embodiments, DTP information <NUM> comprises DTP index <NUM>, and UE <NUM> is operative to identify the selected DTP based on DTP index <NUM>. In the claimed embodiments, UE <NUM> determines a DTP bitmap <NUM> that corresponds to the DTP indicated by DTP information <NUM>, and identifies the set of D2D transmission resources based on the DTP <NUM> bitmap. In the claimed embodiments, for a given DTP, a corresponding DTP bitmap may a respective bit for each individual subframe or other time segment for which that DTP specifies whether D2D transmission is permitted. For example, a DTP bitmap <NUM> that corresponds to DTP <NUM> of <FIG> may comprise forty bits - one for each of the forty subframes comprising the pattern duration of DTP <NUM>.

In various embodiments, based on DTP information <NUM>, UE <NUM> may retrieve DTP bitmap <NUM> from among a plurality of DTP bitmaps contained in memory or storage. In some embodiments, from among the plurality of DTP bitmaps in memory or storage, UE <NUM> may retrieve a DTP bitmap <NUM> that it determines to be associated with DTP index <NUM>. In various embodiments, UE <NUM> may be configured with the plurality of DTP bitmaps via RRC signaling from eNB <NUM>. For example, in some embodiments, eNB <NUM> may configure UE <NUM> with the plurality of DTP bitmaps by sending an RRC message <NUM> that comprises DTP bitmap information <NUM>. In various embodiments, DTP bitmap information <NUM> may be comprised within an information element (IE) of a system information block (SIB) comprised in RRC message <NUM>. In some embodiments, DTP bitmap information <NUM> may comprise the plurality of DTP bitmaps and information specifying which respective one of a plurality of DTP indices corresponds to each of the plurality of DTP bitmaps. In various other embodiments, rather than being configured with DTP bitmap information <NUM> via RRC message <NUM>, UE <NUM> may be configured with DTP bitmap information <NUM> at the time of initial device provisioning. In yet other embodiments, rather than sending DTP information <NUM> that comprises DTP index <NUM>, eNB <NUM> may send DTP information <NUM> that comprises DTP bitmap <NUM> itself.

In some embodiments, UE <NUM> may be operative to determine a DTP applicability interval for the DTP specified by DTP information <NUM>. With respect to the DTP specified by DTP information <NUM>, or any other particular DTP, the term "DTP applicability interval" is defined to denote the time period during which the selection of that DTP remains in effect, such that it should be used to identify any resources needed for D2D transmissions. In various embodiments, the DTP specified by DTP information <NUM> may remain in effect at UE <NUM> until a next D2D control information message is received. In such embodiments, the DTP applicability interval for the DTP specified by DTP information <NUM> may comprise the time interval between receipt of D2D control information <NUM> and receipt of that next D2D control information message.

In some embodiments, UE <NUM> may be operative to use the DTP specified by DTP information <NUM> to identify D2D transmission resources comprised in the DTP applicability interval. In various embodiments, the pattern duration of the DTP specified by DTP information <NUM> may differ from the DTP applicability interval of that DTP. In some embodiments, the specified DTP may remain in effect for a period of time that is longer than the pattern duration of the specified DTP. In various embodiments, UE <NUM> may apply the specified DTP repetitively over time in order to identify D2D transmission resources throughout the DTP applicability interval. For example, UE <NUM> may apply DTP <NUM> of <FIG>, which comprises a pattern length of forty subframes, to each of five forty-subframe subintervals within a DTP applicability interval comprising <NUM> subframes (twenty frames). The embodiments are not limited to this example.

In some embodiments, UE <NUM> may be operative to transmit one or more D2D data messages using D2D transmission resources comprised among those identified based on DTP information <NUM>. For example, in various embodiments, UE <NUM> may be operative to transmit a D2D data message <NUM> to UE <NUM> using D2D transmission resources comprised among the identified resources. In some embodiments, UE <NUM> may be operative to send a D2D notification message <NUM> to UE <NUM> to report the D2D transmission resources to be used to send D2D data message <NUM>. In some embodiments, UE <NUM> may be operative to send D2D notification message <NUM> to UE <NUM> over a direct control channel. In various embodiments, D2D notification message <NUM> may comprise DTP information that is the same as - or similar to - the DTP information <NUM> received in D2D control information message <NUM>. In some embodiments, D2D notification message may comprise the same DTP information <NUM> by design, in order to ensure that information regarding D2D transmission resources is communicated in an unambiguous form that is commonly interpreted by any D2D UE. In some embodiments, D2D notification message <NUM> may comprise a same DTP index <NUM> as was received in D2D control information message <NUM>. In various embodiments, UE <NUM> may use the information comprised in D2D notification message <NUM> to identify the wireless channel resource via which to properly receive D2D data message <NUM>.

In some embodiments, D2D control information <NUM> may also comprise information describing a pattern or other configuration for D2D retransmissions. In various embodiments, D2D control information <NUM> may identify a maximum number of retransmissions to be performed for D2D messages. For example, in some embodiments, D2D control information <NUM> may indicate that a maximum of three retransmissions may be performed for a given D2D transmission. In various embodiments, D2D control information <NUM> may comprise information describing a relationship between D2D transmission resources and D2D retransmission resources. In some embodiments, for example, D2D control information <NUM> may comprise information usable to determine - given the subframe(s) during which a D2D message was transmitted - the subframe(s) during which a retransmission of that D2D message should be performed. The embodiments are not limited to this example.

It is worthy of note that in various embodiments, the techniques described herein may be adapted for use in conjunction with other RRC operations in D2D environments. For example, with respect to a wireless network in which D2D subframes are configured, various D2D subframe channels, such as one or more of a D2D data channel, a D2D discovery channel, a D2D control channel, and/or another type of D2D channel could be defined in analogous fashion as the DTPs discussed above, using repeated bitmap patterns. Likewise, the aforementioned DTP bitmaps could be adapted for use as D2D subframe bitmaps, and D2D subframe pattern indices could be defined for use, via RRC signaling, to identify D2D subframe configurations that are selected and/or applied. In various embodiments, the aforementioned DTP indices and/or DTP bitmaps could be used to specify patterns within pre-allocated pools of resources for D2D operations. In some embodiments, DTP bitmaps could be used to directly specify resources on a multiple frame basis in a fashion similar to a defined mechanism of channel state information (CSI) subframe pattern configuration.

Operations for the above embodiments may be further described with reference to the following figures and accompanying examples. Some of the figures may include a logic flow. Although such figures presented herein may include a particular logic flow, it can be appreciated that the logic flow merely provides an example of how the general functionality as described herein can be implemented. Further, the given logic flow does not necessarily have to be executed in the order presented unless otherwise indicated. In addition, the given logic flow may be implemented by a hardware element, a software element executed by a processor, or any combination thereof.

<FIG> illustrates one embodiment of a logic flow <NUM> such as may be representative of operations that may be performed in some embodiments by UE <NUM>. As shown in <FIG>, a D2D control information message may be received at <NUM> that comprises D2D transmission pattern information. For example, UE <NUM> may be operative to receive D2D control information <NUM> from eNB <NUM> that comprises DTP information <NUM>. At <NUM>, a set of D2D transmission resources may be identified based on the D2D transmission pattern information. For example, UE <NUM> may be operative to identify a set of D2D transmission resources based on a DTP index <NUM> comprised in DTP information <NUM>. At <NUM>, D2D control information may be sent to report the set of D2D transmission resources. For example, UE <NUM> may be operative to send D2D notification message <NUM> to report the identified set of D2D transmission resources to UE <NUM>. At <NUM>, one or more D2D data messages may be sent using D2D transmission resources comprised among the identified set of D2D transmission resources. For example, UE <NUM> may be operative to send one or more D2D data messages <NUM> to UE <NUM> using D2D transmission resources comprised among those it has identified based on DTP index <NUM>. The embodiments are not limited to these examples.

It is worthy of note that in some embodiments, a D2D UE performing operations of logic flow <NUM> may operate in an autonomous mode according to which it selects the DTP itself. In such embodiments, rather than performing operations <NUM> and <NUM>, the D2D UE may select the DTP and then proceed directly to <NUM>, where it may send D2D control information comprising the a DTP index for the selected DTP.

<FIG> illustrates one embodiment of a logic flow <NUM> such as may be representative of operations that may be performed in various embodiments by eNB <NUM>. As shown in <FIG>, a D2D transmission pattern may be selected at <NUM> from among a plurality of defined D2D transmission patterns. For example, eNB <NUM> may be operative to select a D2D transmission pattern from among a plurality of defined D2D transmission patterns. At <NUM>, a DTP index for the selected D2D transmission pattern may be identified. For example, eNB <NUM> may be operative to identify a DTP index <NUM> for a D2D transmission pattern that it has selected. At <NUM>, the selected D2D transmission pattern may be reported by sending D2D control information comprising the D2D index. For example, eNB <NUM> may be operative to report a D2D transmission pattern that it has selected by sending DTP information <NUM> comprising the DTP index <NUM> for the selected D2D transmission pattern. The embodiments are not limited to these examples.

<FIG> illustrates an embodiment of a storage medium <NUM>. Storage medium <NUM> may comprise any non-transitory computer-readable storage medium or machine-readable storage medium, such as an optical, magnetic or semiconductor storage medium. In various embodiments, storage medium <NUM> may comprise an article of manufacture. In some embodiments, storage medium <NUM> may store computer-executable instructions, such as computer-executable instructions to implement logic flow <NUM> of <FIG>. Examples of a computer-readable storage medium or machine-readable storage medium may include any tangible media capable of storing electronic data, including volatile memory or non-volatile memory, removable or non-removable memory, erasable or non-erasable memory, writeable or re-writeable memory, and so forth. Examples of computer-executable instructions may include any suitable type of code, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, object-oriented code, visual code, and the like.

<FIG> illustrates an embodiment of a storage medium <NUM>. Storage medium <NUM> may comprise any non-transitory computer-readable storage medium or machine-readable storage medium, such as an optical, magnetic or semiconductor storage medium. In various embodiments, storage medium <NUM> may comprise an article of manufacture. In some embodiments, storage medium <NUM> may store computer-executable instructions, such as computer-executable instructions to implement logic flow <NUM> of <FIG>. Examples of a computer-readable/machine-readable storage medium and of computer-executable instructions may include - without limitation - any of the respective examples mentioned above in reference to storage medium <NUM> of <FIG>.

<FIG> illustrates an embodiment of a communications device <NUM> that may implement one or more of eNB <NUM>, UE <NUM>, UE <NUM>, logic flow <NUM> of <FIG>, logic flow <NUM> of <FIG>, storage medium <NUM> of <FIG>, and storage medium <NUM> of <FIG>. In various embodiments, device <NUM> may comprise a logic circuit <NUM>. The logic circuit <NUM> may include physical circuits to perform operations described for one or more of eNB <NUM>, UE <NUM>, UE <NUM>, logic flow <NUM> of <FIG>, and logic flow <NUM> of <FIG>, for example. As shown in <FIG>, device <NUM> may include a radio interface <NUM>, baseband circuitry <NUM>, and computing platform <NUM>, although the embodiments are not limited to this configuration.

The device <NUM> may implement some or all of the structure and/or operations for one or more of eNB <NUM>, UE <NUM>, UE <NUM>, logic flow <NUM> of <FIG>, logic flow <NUM> of <FIG>, storage medium <NUM> of <FIG>, storage medium <NUM> of <FIG>, and logic circuit <NUM> in a single computing entity, such as entirely within a single device. Alternatively, the device <NUM> may distribute portions of the structure and/or operations for one or more of eNB <NUM>, UE <NUM>, UE <NUM>, logic flow <NUM> of <FIG>, logic flow <NUM> of <FIG>, storage medium <NUM> of <FIG>, storage medium <NUM> of <FIG>, and logic circuit <NUM> across multiple computing entities using a distributed system architecture, such as a client-server architecture, a <NUM>-tier architecture, an N-tier architecture, a tightly-coupled or clustered architecture, a peer-to-peer architecture, a master-slave architecture, a shared database architecture, and other types of distributed systems.

In one embodiment, radio interface <NUM> may include a component or combination of components adapted for transmitting and/or receiving single-carrier or multi-carrier modulated signals (e.g., including complementary code keying (CCK), orthogonal frequency division multiplexing (OFDM), and/or single-carrier frequency division multiple access (SC-FDMA) symbols) although the embodiments are not limited to any specific over-the-air interface or modulation scheme. Radio interface <NUM> may include, for example, a receiver <NUM>, a frequency synthesizer <NUM>, and/or a transmitter <NUM>. Radio interface <NUM> may include bias controls, a crystal oscillator and/or one or more antennas <NUM>-f. In another embodiment, radio interface <NUM> may use external voltage-controlled oscillators (VCOs), surface acoustic wave filters, intermediate frequency (IF) filters and/or RF filters, as desired. Due to the variety of potential RF interface designs an expansive description thereof is omitted.

Baseband circuitry <NUM> may communicate with radio interface <NUM> to process receive and/or transmit signals and may include, for example, an analog-to-digital converter <NUM> for down converting received signals, a digital-to-analog converter <NUM> for up converting signals for transmission. Further, baseband circuitry <NUM> may include a baseband or physical layer (PHY) processing circuit <NUM> for PHY link layer processing of respective receive/transmit signals. Baseband circuitry <NUM> may include, for example, a medium access control (MAC) processing circuit <NUM> for MAC/data link layer processing. Baseband circuitry <NUM> may include a memory controller <NUM> for communicating with MAC processing circuit <NUM> and/or a computing platform <NUM>, for example, via one or more interfaces <NUM>.

In some embodiments, PHY processing circuit <NUM> may include a frame construction and/or detection module, in combination with additional circuitry such as a buffer memory, to construct and/or deconstruct communication frames. Alternatively or in addition, MAC processing circuit <NUM> may share processing for certain of these functions or perform these processes independent of PHY processing circuit <NUM>. In some embodiments, MAC and PHY processing may be integrated into a single circuit.

The computing platform <NUM> may provide computing functionality for the device <NUM>. As shown, the computing platform <NUM> may include a processing component <NUM>. In addition to, or alternatively of, the baseband circuitry <NUM>, the device <NUM> may execute processing operations or logic for one or more of eNB <NUM>, UE <NUM>, UE <NUM>, logic flow <NUM> of <FIG>, logic flow <NUM> of <FIG>, storage medium <NUM> of <FIG>, storage medium <NUM> of <FIG>, and logic circuit <NUM> using the processing component <NUM>. The processing component <NUM> (and/or PHY <NUM> and/or MAC <NUM>) may comprise various hardware elements, software elements, or a combination of both. Examples of hardware elements may include devices, logic devices, components, processors, microprocessors, circuits, processor circuits, circuit elements (e.g., transistors, resistors, capacitors, inductors, and so forth), integrated circuits, application specific integrated circuits (ASIC), programmable logic devices (PLD), digital signal processors (DSP), field programmable gate array (FPGA), memory units, logic gates, registers, semiconductor device, chips, microchips, chip sets, and so forth. Examples of software elements may include software components, programs, applications, computer programs, application programs, system programs, software development programs, machine programs, operating system software, middleware, firmware, software modules, routines, subroutines, functions, methods, procedures, software interfaces, application program interfaces (API), instruction sets, computing code, computer code, code segments, computer code segments, words, values, symbols, or any combination thereof. Determining whether an embodiment is implemented using hardware elements and/or software elements may vary in accordance with any number of factors, such as desired computational rate, power levels, heat tolerances, processing cycle budget, input data rates, output data rates, memory resources, data bus speeds and other design or performance constraints, as desired for a given implementation.

The computing platform <NUM> may further include other platform components <NUM>. Other platform components <NUM> include common computing elements, such as one or more processors, multi-core processors, co-processors, memory units, chipsets, controllers, peripherals, interfaces, oscillators, timing devices, video cards, audio cards, multimedia input/output (I/O) components (e.g., digital displays), power supplies, and so forth. Examples of memory units may include without limitation various types of computer readable and machine readable storage media in the form of one or more higher speed memory units, such as read-only memory (ROM), random-access memory (RAM), dynamic RAM (DRAM), Double-Data-Rate DRAM (DDRAM), synchronous DRAM (SDRAM), static RAM (SRAM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, polymer memory such as ferroelectric polymer memory, ovonic memory, phase change or ferroelectric memory, silicon-oxide-nitride-oxide-silicon (SONOS) memory, magnetic or optical cards, an array of devices such as Redundant Array of Independent Disks (RAID) drives, solid state memory devices (e.g., USB memory, solid state drives (SSD) and any other type of storage media suitable for storing information.

Device <NUM> may be, for example, an ultra-mobile device, a mobile device, a fixed device, a machine-to-machine (M2M) device, a personal digital assistant (PDA), a mobile computing device, a smart phone, a telephone, a digital telephone, a cellular telephone, user equipment, eBook readers, a handset, a one-way pager, a two-way pager, a messaging device, a computer, a personal computer (PC), a desktop computer, a laptop computer, a notebook computer, a netbook computer, a handheld computer, a tablet computer, a server, a server array or server farm, a web server, a network server, an Internet server, a work station, a mini-computer, a main frame computer, a supercomputer, a network appliance, a web appliance, a distributed computing system, multiprocessor systems, processor-based systems, consumer electronics, programmable consumer electronics, game devices, display, television, digital television, set top box, wireless access point, base station, node B, subscriber station, mobile subscriber center, radio network controller, router, hub, gateway, bridge, switch, machine, or combination thereof. Accordingly, functions and/or specific configurations of device <NUM> described herein, may be included or omitted in various embodiments of device <NUM>, as suitably desired.

Embodiments of device <NUM> may be implemented using single input single output (SISO) architectures. However, certain implementations may include multiple antennas (e.g., antennas <NUM>-f) for transmission and/or reception using adaptive antenna techniques for beamforming or spatial division multiple access (SDMA) and/or using MIMO communication techniques.

The components and features of device <NUM> may be implemented using any combination of discrete circuitry, application specific integrated circuits (ASICs), logic gates and/or single chip architectures. Further, the features of device <NUM> may be implemented using microcontrollers, programmable logic arrays and/or microprocessors or any combination of the foregoing where suitably appropriate. It is noted that hardware, firmware and/or software elements may be collectively or individually referred to herein as "logic" or "circuit.

It should be appreciated that the exemplary device <NUM> shown in the block diagram of <FIG> may represent one functionally descriptive example of many potential implementations. Accordingly, division, omission or inclusion of block functions depicted in the accompanying figures does not infer that the hardware components, circuits, software and/or elements for implementing these functions would be necessarily be divided, omitted, or included in embodiments.

<FIG> illustrates an embodiment of a broadband wireless access system <NUM>. As shown in <FIG>, broadband wireless access system <NUM> may be an internet protocol (IP) type network comprising an internet <NUM> type network or the like that is capable of supporting mobile wireless access and/or fixed wireless access to internet <NUM>. In one or more embodiments, broadband wireless access system <NUM> may comprise any type of orthogonal frequency division multiple access (OFDMA)-based or single-carrier frequency division multiple access (SC-FDMA)-based wireless network, such as a system compliant with one or more of the 3GPP LTE Specifications and/or IEEE <NUM> Standards, and the scope of the claimed subject matter is not limited in these respects.

In the exemplary broadband wireless access system <NUM>, radio access networks (RANs) <NUM> and <NUM> are capable of coupling with evolved node Bs (eNBs) <NUM> and <NUM>, respectively, to provide wireless communication between one or more fixed devices <NUM> and internet <NUM> and/or between or one or more mobile devices <NUM> and Internet <NUM>. One example of a fixed device <NUM> and a mobile device <NUM> is device <NUM> of <FIG>, with the fixed device <NUM> comprising a stationary version of device <NUM> and the mobile device <NUM> comprising a mobile version of device <NUM>. RANs <NUM> and <NUM> may implement profiles that are capable of defining the mapping of network functions to one or more physical entities on broadband wireless access system <NUM>. eNBs <NUM> and <NUM> may comprise radio equipment to provide RF communication with fixed device <NUM> and/or mobile device <NUM>, such as described with reference to device <NUM>, and may comprise, for example, the PHY and MAC layer equipment in compliance with a 3GPP LTE Specification or an IEEE <NUM> Standard. eNBs <NUM> and <NUM> may further comprise an IP backplane to couple to Internet <NUM> via RANs <NUM> and <NUM>, respectively, although the scope of the claimed subject matter is not limited in these respects.

Broadband wireless access system <NUM> may further comprise a visited core network (CN) <NUM> and/or a home CN <NUM>, each of which may be capable of providing one or more network functions including but not limited to proxy and/or relay type functions, for example authentication, authorization and accounting (AAA) functions, dynamic host configuration protocol (DHCP) functions, or domain name service controls or the like, domain gateways such as public switched telephone network (PSTN) gateways or voice over internet protocol (VoIP) gateways, and/or internet protocol (IP) type server functions, or the like. However, these are merely example of the types of functions that are capable of being provided by visited CN <NUM> and/or home CN <NUM>, and the scope of the claimed subject matter is not limited in these respects. Visited CN <NUM> may be referred to as a visited CN in the case where visited CN <NUM> is not part of the regular service provider of fixed device <NUM> or mobile device <NUM>, for example where fixed device <NUM> or mobile device <NUM> is roaming away from its respective home CN <NUM>, or where broadband wireless access system <NUM> is part of the regular service provider of fixed device <NUM> or mobile device <NUM> but where broadband wireless access system <NUM> may be in another location or state that is not the main or home location of fixed device <NUM> or mobile device <NUM>.

Fixed device <NUM> may be located anywhere within range of one or both of eNBs <NUM> and <NUM>, such as in or near a home or business to provide home or business customer broadband access to Internet <NUM> via eNBs <NUM> and <NUM> and RANs <NUM> and <NUM>, respectively, and home CN <NUM>. It is worthy of note that although fixed device <NUM> is generally disposed in a stationary location, it may be moved to different locations as needed. Mobile device <NUM> may be utilized at one or more locations if mobile device <NUM> is within range of one or both of eNBs <NUM> and <NUM>, for example. In accordance with one or more embodiments, operation support system (OSS) <NUM> may be part of broadband wireless access system <NUM> to provide management functions for broadband wireless access system <NUM> and to provide interfaces between functional entities of broadband wireless access system <NUM>. Broadband wireless access system <NUM> of <FIG> is merely one type of wireless network showing a certain number of the components of broadband wireless access system <NUM>, and the scope of the claimed subject matter is not limited in these respects.

Some embodiments may be implemented, for example, using a machine-readable medium or article which may store an instruction or a set of instructions that, if executed by a machine, may cause the machine to perform a method and/or operations in accordance with the embodiments. Such a machine may include, for example, any suitable processing platform, computing platform, computing device, processing device, computing system, processing system, computer, processor, or the like, and may be implemented using any suitable combination of hardware and/or software. The machine-readable medium or article may include, for example, any suitable type of memory unit, memory device, memory article, memory medium, storage device, storage article, storage medium and/or storage unit, for example, memory, removable or non-removable media, erasable or non-erasable media, writeable or re-writeable media, digital or analog media, hard disk, floppy disk, Compact Disk Read Only Memory (CD-ROM), Compact Disk Recordable (CD-R), Compact Disk Rewriteable (CD-RW), optical disk, magnetic media, magneto-optical media, removable memory cards or disks, various types of Digital Versatile Disk (DVD), a tape, a cassette, or the like. The instructions may include any suitable type of code, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, encrypted code, and the like, implemented using any suitable high-level, low-level, object-oriented, visual, compiled and/or interpreted programming language.

It is emphasized that the Abstract of the Disclosure is provided to comply with <NUM> C. § <NUM>(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate preferred embodiment. In the appended claims, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein," respectively. Moreover, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

Claim 1:
A method of performing device-to-device, D2D, data transmission using resources of an identified set of subframes, the method comprising the steps of:
identifying a device-to-device transmission pattern, DTP, index based on received D2D control information received via a physical downlink control channel, PDCCH, wherein the DTP specifies a time interval during which D2D transmissions are permitted;
determining a DTP bitmap corresponding to the DTP index;
identifying a set of subframes comprising D2D transmission resources based on the DTP bitmap; and
performing D2D data transmission using resources of the identified set of subframes.