BR112016018457B1 - METHOD, WIRELESS DEVICE, AND NETWORK NODE - Google Patents

Abstract

METHOD, WIRELESS DEVICE, AND, NETWORK NODE. Techniques for distributing and using application codes and discovery filters on device-to-device (D2D) wireless devices. An exemplary method for an advertising device includes receiving, from a coordination node, first and second application codes and associated timing information. The associated timing information defines respective first and second validity intervals for the first and second application codes, such that the first and second validity intervals are at least partially non-overlapping. The method further comprises transmitting subsequently during the first validity interval. one or more discovery messages that include or are based on the first application code and transmit, during the second validity interval, one or more discovery messages that include or are based on the second application code. Corresponding techniques for monitoring devices are also described.

Description

TECHNICAL FIELD

[001] The technology disclosed herein generally relates to wireless communication networks, and more particularly relates to discovery techniques for wireless device-to-device communications.

BACKGROUND

[002] Device-to-device (D2D) communication is a well-known and widely used component of many existing wireless technologies, including ad hoc and cellular networks. Examples include Bluetooth and various variants of the IEEE 802.11 suite of standards, such as WiFi Direct. These example systems operate in unlicensed spectrum.

[003] While the idea of enabling D2D communications as a means of relaying cellular networks has been proposed by some previous work on ad hoc networks, the concept of enabling local D2D communications to reuse cellular spectrum resources concurrently with cellular traffic in progress is relatively new. Because non-orthogonal resource sharing between the cellular and D2D layers has the potential for reuse gain and proximity gain, along with increased resource utilization, the concept of D2D communications underlying cellular networks has received considerable interest in recent years.

[004] The Third Generation Society Project (3GPP) refers to D2D Controlled Networking as "Proximity Services" or "ProSe", and efforts aimed at integrating D2D functionality into the Long Term Evolution (LTE) specifications are under way. path. A ProSe Study Item (SI) recommended supporting D2D operation between wireless devices - called user equipment or UEs per 3GPP - that are out of network coverage, as well as operation between wireless devices in coverage and out of coverage.

[005] Specifically, in 3GPP LTE networks, such LTE Direct (D2D) communication can be used in commercial applications such as cellular network offloading, proximity-based social networking operation. D2D communications involving out-of-coverage operation are expected to be particularly important in so-called national security and public safety services (NSPS), such as in public safety situations where first responders need to communicate with each other and with people in a disaster area. . Both commercial and public safety applications are among the use cases discussed in the feasibility study performed by members of the 3rd Generation Society Project (3GPP) and documented in the "3rd Generation Society Project" report; Technical Specification and System Aspects Group Services; Feasibility Study for Proximity Services (ProSe)," 3GPP TR 22.803, v. 12.2.0 (June 2013), available at www.3gpp.org.

[006] D2D communication entities using an LTE Direct link can reuse the same physical resource blocks ("PRBs", the basic time-frequency resource on the LTE radio link) as used for cellular communications on either the downlink or the top link or both. Reusing radio resources in a controlled manner can lead to increased spectral efficiency at the expense of some increased intra-cell interference.

[007] Typically, D2D communicating entities in an underlying LTE scenario will use upper link (UL) resources, such as UL PRBs or UL time slots, but conceptually it is possible for D2D (LTE Direct) communications to take place on the lower cellular binding (DL) spectrum or at DL time intervals. For ease of presentation, in the present description it is assumed that D2D links use uplink resources, such as uplink PRBs in a Frequency Division Duplexing (FDD) LTE system, or uplink time slots in a Cellular Time Division Duplexing (TDD) system, but the essential ideas expounded here can readily be applied to cases where D2D communications take place in DL spectrum as well.

[008] An important aspect of D2D communications is the concept of "discovery", which deals with the techniques and procedures used by a D2D device to detect the proximity of other devices that are capable of and authorized to engage in D2D communications. D2D.

[009] The 3GPP white paper titled "Study on Architectural Enhancements to Support Proximity-Based Services (ProSe)", briefly outlines several approaches to discovery, including an "LTE-based solution for direct discovery". (3GPP TR 23.703, second 6.1, v 1.1.0 (January 2014)). As shown in this document, a "UE Announcer", i.e. a wireless device that wants to make its services or needs services known to other devices, receives a so-called expression code from a ProSe function in or connected to the LTE network , for example, on a ProSe server, and broadcasts the received expression code. Other wireless devices, referred to in 3GPP documentation as "monitoring UEs", monitor broadcasts from advertising UEs and compare any received expression code to one or more expression codes they may have received previously, to detect the presence of advertising UEs. with whom they are interested in communicating.

[0010] While details of the exact discovery procedures to be performed across 3GPP-compliant devices are still being developed, section 6.1.13 of the 3GPP technical report referenced above describes a network-controlled discovery procedure in which one or more "IDs of application", which can be seen as examples of the "expression codes" discussed above, are allocated to advertiser and monitoring UEs. These application codes have a limited lifetime, and are associated with an expiration timer that starts at the time the application codes are allocated. The advertiser UE is allowed to broadcast a ProSe_Code that includes the application code until the expiration timer expires. Monitoring UEs monitor the appropriate radio resources, "listening" for a ProSe_Code that includes an application code corresponding to an application code that has been allocated to it. Once the validity timer expires, the advertiser UE must initiate a new request to the ProSe function to receive a new application code or codes.

SUMMARY

[0011] According to various embodiments of the techniques now disclosed, more than one access code to be used for advertising purposes is allocated to wireless advertising devices, with each access code having a distinct validity time interval. These access codes used for advertising purposes are called "application codes" here. Also, more than one access code to be used for monitoring purposes is allocated to wireless monitoring devices, again with each access code having a distinct expiration time interval. Shortcodes used for monitoring purposes are called "discovery filters" here. In both cases, time intervals for these codes may be successive or partially overlapping, so as to provide a seamless transition between one access code and another without requiring an intervening request for a new access code.

[0012] An example method is suitable for implementation in a wireless device configured for operation in a wireless communication network and further configured for device-to-device communication with one or more other wireless devices. This exemplary method includes receiving, from a coordination node, first and second application codes and associated timing information. Associated timing information defines respective first and second validity intervals for the first and second application codes such that the first and second validity intervals are at least partially non-overlapping. The method further includes subsequently transmitting, during the first validity interval, one or more discovery messages that include or are based on the first application code, and transmitting, during the second validity interval, one or more discovery messages that include or are based on the first application code. are based on the second application code.

[0013] In some embodiments, the first and second application codes and associated timing are received in response to an application code request sent to the coordination node over the wireless communication network.

[0014] In some embodiments, the associated timing information defines completely non-overlapping first and second validity intervals. In some embodiments, the associated timing information includes first and second time-to-live values, the first and second time-to-live values indicating respective durations of the first and second validity intervals. In some of these prior embodiments, the second validity interval begins at the end of the first validity interval. In others, the associated timing information includes a start time value indicating a start time for the second validity interval such that the second validity interval begins before the end of the first validity interval.

[0015] Another example method is also suitable for a wireless device configured for operation in a wireless communication network and further configured for device-to-device communication with one or more other wireless devices. This example method begins with receiving first and second discovery filters and associated timing information, the associated timing information defining respective first and second validity intervals for the first and second discovery filters, such that the first and second validity intervals are at least partially non-overlapping. The method further includes monitoring, during the first validity interval, a discovery message that includes or is based on the first discovery filter, and monitoring, during the second validity interval, a discovery message that includes or is based on the second filter. of discovery.

[0016] Again, the associated timing information may define completely non-overlapping first and second validity intervals, in some embodiments. In some embodiments, the associated timing information includes first and second time-to-live values, the first and second time-to-live values indicating respective durations of the first and second validity intervals. In some of these prior embodiments, the second validity interval begins at the end of the first validity interval. In others, the associated timing information includes a start time value indicating a start time for the second validity interval, such that the second validity interval begins before the end of the first validity interval,

[0017] Another exemplary embodiment in accordance with the various techniques and apparatus set forth herein is a suitable method for implementation in one or more network nodes adapted to provide D2D-related services to wireless devices operating in a wireless communication network. This exemplary method begins with receiving an application code request from a first wireless device, and continues with sending first and second application codes and associated timing information to the first wireless device. Again, the associated timing information defines respective first and second validity intervals for the first and second application codes such that the first and second validity intervals for the first and second application codes are at least partially non-overlapping.

[0018] In some embodiments, the one or more network nodes are also configured to provide discovery filters to one or more wireless devices, for monitoring purposes. Thus, in some embodiments, the method further includes receiving a discovery filter request from a second wireless device and sending first and second discovery filters and associated timing information to the second wireless device. The associated timing information defines respective first and second validity intervals for the first and second discovery filters such that the first and second validity intervals for the first and second discovery filters are at least partially non-overlapping. In some embodiments, the first and second discovery filters correspond to the first and second application codes, respectively, such that monitoring by the second wireless device using the first and second discovery filters will detect discovery messages based on the first and second application codes , respectively.

[0019] In the detailed description that follows, the methods summarized above are described in detail. Furthermore, corresponding apparatus configured to perform these methods and variants thereof are described.

BRIEF DESCRIPTION OF THE FIGURES

[0020] Figure 1 is a schematic diagram illustrating a portion of an example Long Term Evolution (LTE) network.

[0021] Figure 2 is a block diagram of an example wireless device in accordance with some embodiments of the expounded techniques and apparatus.

[0022] Figure 3 is a block diagram of an example network node according to some embodiments of the expounded techniques and apparatus.

[0023] Figure 4 illustrates device-to-device (D2D) network and off-network operation.

[0024] Figure 5 illustrates the current situation for the distribution and use of access codes.

[0025] Figure 6 illustrates an example of the distribution and use of access codes according to some of the techniques exposed here.

[0026] Figure 7 illustrates another example of the distribution and use of access codes according to some of the techniques exposed here.

[0027] Figure 8 is a process flowchart illustrating a sample method run on a device without Gos from D2D Advertiser.

[0028] Figure 9 is a process flowchart illustrating an example method performed on a device without monitoring D2D Gos.

[0029] Figure 10 illustrates the Roaming Reference Architecture illustrated in 3GPP TR 23.703, including the reference point used to request and receive access codes for an advertising UE and request and receive discovery Gltrs for a monitoring UE.

[0030] Figure 11 is another process flowchart illustrating a sample method run on a device without Gos from D2D Advertiser.

[0031] Figure 12 is a process flow chart illustrating another example method run on a device without monitoring D2D floss.

[0032] Figure 13 is a process flowchart illustrating an example method executed on a network node.

[0033] Figure 14 is a block diagram illustrating functional elements of an exemplary device or computer-readable medium in accordance with embodiments of the foregoing techniques.

DETAILED DESCRIPTION

|0034] Inventive concepts will now be described more fully below with reference to the accompanying drawings, in which examples of embodiments of inventive concepts are illustrated. These inventive concepts can, however, be realized in many different ways and should not be construed as limited to the embodiments published here. Rather, these embodiments are provided so that this description will be thorough and complete, and will fully convey the range of inventive concepts present to those skilled in the art. It should also be noted that these arrangements are not mutually exclusive. Components of one embodiment may be tacitly assumed to be present or used in another embodiment.

[0035] For purposes of illustration and explanation only, some embodiments of the present inventive concepts are described here in the context of operating in or in association with a Radio Access Network (RAN) that communicates via radio communication channels with terminals mobile devices (also called wireless terminals or UEs).

|0036] In some embodiments of a RAN, for example, multiple base stations may be connected (eg via landlines or radio channels) to a radio network controller (RNC). A radio network controller, also sometimes called a base station controller (BSC), can supervise and coordinate various activities of the various base stations connected to it. A radio network controller can be connected to one or more core networks. According to some other embodiments of a RAN, base stations can be connected to one or more core networks without a separate RNC in between, for example with functionality of an RNC implemented in the base stations and/or core networks.

[0037] As used herein, the terms "mobile terminal", "wireless terminal", "wireless device", "user equipment", or "UE" may be used to refer to any device that receives data from and transmits data to a communication network, any of which may be, for example, a mobile telephone ("cellular phone"), laptop/laptop computer, pocket computer, hand held computer, desktop computer, a machine type device for machine (M2M) or MTC, a sensor with a wireless communication interface, etc. Devices of any of these types can be adapted, in accordance with known techniques and in accordance with the additional techniques set forth herein, for operation in a device-to-device (D2D) mode, where such operation may include the transmission and reception of certain signals that are similar to or identical with corresponding signals used when operating within a cellular network, i.e., in a device-to-base station operating mode.

[0038] Note that although specification terminology for the Long Term Evolution (LTE; also called the Evolved Universal Terrestrial Radio Access Network, or E-UTRAN and/or the Universal Mobile Telecommunications System (UMTS) is used in this description to exemplify embodiments of the inventive concepts, this should not be seen as limiting the scope of the techniques now exposed to these systems only. Devices designed for use in other wireless systems, including variations and successors of 3GPP LTE and WCDMA systems, WiMAX ( Worldwide Interoperability for Microwave Access), UMB (Mobile Ultra Broadband), HSDPA (High Speed Lower Link Packet Access), GSM (Global System for Mobile Communications), etc. of present inventive concepts exposed here.

[0039] Also note that terminology such as base station (also called NodeB, eNodeB, or Evolved B Node) and wireless terminal or mobile terminal (also called User Equipment node or UE) should be considered non-limiting and does not imply a certain hierarchical relationship between the two. In general, a base station (e.g. a "NodeB" or "eNodeB") and a wireless terminal (e.g. a "UE") can be considered as examples of respective different communication devices that communicate with each other over of a wireless radio channel.

[0040| The Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) includes base stations called enhanced NodeBs (eNBs or eNodeBs), providing the E-UTRA user plane and control plane protocol terminations for the UE. The eNBs are interconnected with each other using the X2 interface. The eNBs are also connected using the SI interface to the EPC (Evolved Packet Core), more specifically to the MME (Mobility Management Entity) through the Sl-MME interface and to the Service Portal (S-GW) through the interface Sl-U. The SI interface supports many-to-many relationship between MMEs/S-GWs and eNBs. A simplified view of the E-UTRAN architecture is illustrated in Figure 1.

[0041] The eNB 110 hosts functionality such as Radio Resource Management (RRM), radio bearer control, admission control, header compression of data from user plane to service portal, and/or routing of data from user plan for the service portal. The MME 120 is the control node that processes the signaling between the UE and the CN (core network). Significant functions of the MME 120 are related to connection management and bearer management, which are operated by Accessless Stratum (NAS) protocols. The S-GW 130 is the anchor point for UE mobility, and also includes other functionality such as temporary DL data storage (downlink) while the UE is being located by radio, routing and packet forwarding to the correct eNB, and/or accumulation of information for legal collection and interception. The PDN Gateway (P-GW, not shown in Figure 1) is the node responsible for UE IP address allocation, as well as implementing Quality of Service (QoS) (as further discussed below). The reader is referred to 3GPP TS 36.300 and 3GPP TS 23.401, as well as the references provided therein, for further details of functionality of the different nodes.

[0042] Several of the techniques and methods described here are implemented using radio circuits, electronic data processing circuits, and other electronic hardware provided in a mobile terminal. Figure 2 illustrates features of an example mobile terminal 200 in accordance with various embodiments of the present invention. Mobile terminal 200 may be a LIE configured for operation with an LTE wireless communication network (E-UTRAN), for example, as well as for operation in a device-to-device mode, includes a radio transceiver circuit 220 configured to communicate with one or more base stations as well as a processing circuit 210 configured to process the signals transmitted and received by the transceiver unit 220. Transceiver circuit 220 includes a transmitter 225 coupled to one or more transmit antennas 228 and receiver 230 coupled to one or more receiver antennas 233. The same antennas 228 and 233 may be used for both transmission and reception.

[0043] Receiver 230 and transmitter 225 use known radio processing and signal processing components and techniques, typically in accordance with a particular telecommunications standard such as the 3GPP standards for LTE. Note also that transmitter circuitry 220 may include separate radio and/or baseband circuitry for each of two or more different types of radio access network, in some embodiments. The same applies to antennas - while in some cases, one or more antennas may be used for accessing multiple types of networks, in other cases one or more antennas may be tailored specifically to a particular radio access network or networks. Because the various engineering details and compromises associated with the design and implementation of such circuits are well known and are unnecessary to a complete understanding of the invention, further details are not shown here.

[0044] Processing circuit 210 includes one or more processors 240 coupled to one or more memory devices 250 comprising a data storage memory 255 and a program storage memory 260. Processor 240, identified as CPU 240 in Figure 2 , may be a microprocessor, microcontroller, or digital signal processor, in some embodiments. More generally, processing circuitry 210 may include a processor/firmware combination, or specialized digital hardware, or a combination thereof. Memory 250 can include one or more types of memory such as read only memory (ROM), random access memory, cache memory, flash memory devices, optical storage devices, and the like. Because terminal 200 can support multiple radio access networks, including, for example, a wide area RAN such as LTE as well as a wireless local area network (WLAN), processing circuit 210 can include dedicated separate processing resources. to one or more radio access technologies, in some modalities. Again, because the various details and engineering compromises associated with the design of baseband processing circuits for mobile devices are well known and are unnecessary to a complete understanding of the invention, further details are not shown here.

[0045] Typical functions of processing circuit 210 include modulation and encoding of transmitted signals and the demodulation and decoding of received signals. In various embodiments of the present invention, processing circuitry 210 is adapted, using suitable program code stored in program storage memory 260, for example, to perform one of the techniques specifically described herein, including, for example, one or more of methods illustrated in Figures 4 and 5 and variants thereof. Of course, it will be appreciated that not all steps in these techniques are necessarily performed on a single microprocessor or even a single module.

[0046] Mobile terminal 200 may additionally include one or more additional interface circuits, depending on the specific application for the unit. Typically, mobile terminal 270 includes connector interface circuitry 270. In some embodiments, connector interface circuitry 270 may consist of no more than terminals and associated hardware to support charging an onboard battery (not shown) or providing power. direct current (DC) for the illustrated circuits. More often, connector interface circuitry 270 additionally includes a wired communication and/or control interface, which may operate in accordance with proprietary signaling and message formats in some embodiments, or in accordance with a standardized interface definition. , in others. For example, connector interlace 270 may include terminals and associated hardware to support the popular Universal Serial Bus (USB) interface. It will be appreciated that while connector interface circuitry 270 includes at least the receiver and activation circuitry necessary to support such an interface and may additionally include specialized hardware/firmware, part of the interface functionality may be provided by CPU 240, configured with firmware and/or appropriate software in memory 250, in some embodiments.

[0047] Mobile terminal 200 may additionally include local area network (LAN) interface circuitry 280, in some embodiments. In some embodiments, for example, LAN interface circuit 280 may provide support for wireless LAN (WLAN) functionality, such as in accordance with well-known Wi-Fi standards. In some embodiments, LAN interface circuitry 280 may include an appropriate antenna or antennas. In other embodiments, the LAN interface circuit 280 can make use of one or more common antenna structures that provide reception and/or transmission of WLAN signals as well as wide area RAN signals. In some embodiments, LAN interface circuitry 280 can be relatively self-contained, as it includes all of the hardware, firmware, and/or software necessary to perform LAN functionality, including associated protocol stacks. In other embodiments, at least portions of the LAN functionality may be performed by processing circuitry 210.

[0048] Still further, the mobile terminal 200 may include user interface circuitry 290, which may include, for example, circuitry and/or associated hardware for one or more switches, buttons, keyboards, touch screens, and the like, to user input, as well as one or more speakers and/or displays for output. Of course, some mobile terminals, such as those designed for machine-to-machine applications or for insertion into another device (eg, a laptop) may have only a subset of these input/output devices, or none at all.

[0049] As discussed above, 3GPP is developing specifications for proximity services, often called "ProSe", which include specifications for device-to-device (D2D) operation utilizing the same time-frequency resources used by LTE networks. in each of several possible operational modes that include coverage operation (where the D2D devices involved are all within the coverage area of an LTE network), out-of-coverage operation (where none of the devices are within the coverage area of an LTE network), and combinations of both, As noted above, D2D communications involving out-of-coverage operation are expected to be particularly important in so-called national security and public safety services (NSPS), such as in public safety situations where first responders need to communicate with each other and with people in a disaster area.

[0050] Several of the techniques and processes described above can be implemented in a network node, such as in a wireless communication system core network node, or in a so-called ProSe server. Note that ProSe's server functionality can be implemented on any of a variety of physical nodes, which can incorporate other functionality as well. So, for example, ProSe functionality could be implemented in an eNB or another in an LTE network node, or in a node in an Evolved Packet Core (EPC). Alternatively, ProSe functionality can be implemented in a node that is outside the RAN, for example, in the core network, or even outside both the RAN and the core network.

[0051] Figure 3 is a schematic illustration of a node 1 in which a method embodying any of the network-based techniques just described can be implemented. A computer program for controlling node 1 to perform a method embodying any of the foregoing techniques is stored in program storage 30, which includes one or more memory devices. Data used during performance of a method embodying the present invention is stored in a data memory 20, which also includes one or more memory devices, one or more of which may be the same as those used for program storage 30, in some embodiments . During performance of a method embodying the present invention, program steps are fetched from program storage 30 and executed by a Central Processing Unit (CPU) 10, retrieving data as required from data storage 20. Output information resulting from performance of A method embodying the present invention can be stored voka in data storage 20, or sent to an Input/Output (I/O) interface 40, which includes a network interface for sending and receiving data to and from other network nodes. network, for example via an X2 and/or S1 interface, and which may also include a radio transceiver for communicating with one or more terminals. The CPU 10 and its associated data store 20 and program store 30 may collectively be called a "processing circuit". It will be appreciated that variations of this processing circuit are possible, including circuits that include one or more of various types of programmable circuit elements, e.g., microprocessors, microcontrollers, digital signal processors, field programmable application-specific integrated circuits, and the like. , as well as processing circuits where all or part of the processing functionality described here is performed using dedicated digital logic.

[0052] Accordingly, in various embodiments of the invention, processing circuits, such as the CPU 10, data store 20, and program store 30 in Figure 3, are configured to perform one or more of the techniques described in detail above. It should be appreciated that the processing circuit, when configured with appropriate program code, can be understood to include a number of functional "modules", where each module includes program code to perform the corresponding function, when executed by an appropriate processor. Of course, it will be appreciated that not all steps of a given technique are necessarily performed on a single microprocessor or, equivalently, that all functional modules in a given embodiment are implemented with a single processing circuit,

[0053] Figure 4 illustrates basic principles for D2D communication within LTE, for both in coverage and out of coverage scenarios. A control node, for example an eNode B or a cluster head. controls communication on a carrier of frequency f_0. (A cluster head is a node, among a "cluster" of nodes in an ad hoc network, that is responsible for routing packets to and from other clusters.) In a first scenario, devices A and B are communicating directly over a D2D link, and both devices are within network coverage (NW) of control node 410. Control node 410 then allocates radio resources to devices A and B for use in D2D communication. , devices C and D can have D2D communication out of range of a control node, i.e. out of coverage. In this case, the D2D communication devices are using preconfigured time-frequency resources (t- fj for D2D communication. Preconfiguration of these features may be by default, for example. In some cases, preconfiguration of these features may depend on device capabilities. For example, a device could be categorized as a device of type NSPS Type 1 device, for police use, while the other is categorized as an NSPS Type 2 device, for military use. The preconfiguration of these different devices can then differ depending on their respective capabilities.

[0054] As discussed above, procedures for direct discovery are being developed, whereby some wireless devices, called "advertising devices" or "advertising UEs", are configured to transmit advertisement messages indicating their desire to communicate with others D2D devices. Other wireless devices, called "monitoring devices", "monitoring UEs", "discovery devices", "discovery UEs" or similar, are configured to monitor the appropriate radio resources to listen for transmitted advertisement messages. Advertisements can be application specific, so some devices can be both advertising devices and monitoring devices at the same time, for example. for different applications.

[0055] As discussed briefly above, 3GPP is working on needed enhancements to support Proximity Based Services (ProSe). More specifically, 3GPP has published a technical report (3GPP TR 23.703, v. 1.1.0 (January 2014), available at www.3gpp.org), which describes techniques that can be employed to allow D2D devices to discover other devices in the roundness. More particularly, these discovery procedures can be used to discover other wireless devices that are using certain specific applications that are of interest. Thus, Section 6.1.13 of 3GPP TR 23.703 describes a network-controlled discovery procedure in which one or more "application IDs", which can be seen as examples of the "expression codes" mentioned above, are allocated to advertiser UEs and monitoring. These application IDs have a limited lifetime, and are associated with an expiration timer that starts at the time the application codes are allocated. The validity interval limited by the validity timer can be considered "time to live" (TTL) for the application code.

[0056] The advertiser UE is allowed to broadcast a ProSe_Code that includes the application ID until the expiration timer expires. Monitoring UEs monitor the appropriate radio resources, "listening" for a ProSe_Code that includes an application ID corresponding to an application ID that has been allocated to it. The Application ID/code is used in the discovery procedure to "match" an advertisement, i.e. to determine whether an advertising UE has an application that is of interest to the monitoring UE. Once the expiration timer expires, i.e. once the TTL expires, a new application code must be used. According to the procedures defined by the 3GPP Technical Report - 3GPP TR 23.703 v 1.1.0, an advertiser UE must initiate a new request to the ProSe function to receive a new application code or codes.

[0057] It should be appreciated that various terms may apply to the "application IDs" and "expression codes" described herein, including "application code", "access code", "discovery code", and the like. In some cases, one term could apply to a code used by an advertising device, while another term applies to a code used by a monitoring device, even while these codes may have the same value. For example, the terms "access filter", "discovery filter", and the like may be used to refer to an application code (or a parameter corresponding to an application code) used by a monitoring device to detect advertisements. of interest. For purposes of the techniques just discussed, all of these terms should be understood to be interchangeable, except as otherwise indicated by the contexts in which the terms appear. For clarity, however, the description of various embodiments will use the term "application code" to refer to those codes that are distributed to wireless devices for annunciation purposes, while the term "discovery filter" may be used to refer to those codes that are distributed to wireless devices for monitoring purposes. These codes may be identical, in some embodiments, or may have common components or components that may be derived from one another, in various embodiments.

[0058] The solution described in 3GPP TR 23.703, v 1.1.0 (January 2014), requires monitoring and advertising UEs to request new application codes when the TTL of the existing Application code expires. This can cause a signal storm for functionality that allocates these codes when TTL expires. Additionally, any delays associated with these new orders may result in openings in advertisements and/or monitoring. This approach does not provide seamless functionality for endpoints trying to discover other endpoints.

[0059] Figure 5 illustrates the situation described in 3GPP TR 23703, v 1.1.0. (Note that Figure 5 refers to "access codes" and "access filters". For purposes of the present description, these terms should be understood to be interchangeable with the "application codes and "application IDs" discussed above). During a first time interval, the advertising UE uses a first advertising code, "AC1", while a monitoring UE (called a "discoverer UE" in Figure 5) monitors advertisements using a first "access filter". advertiser and UE discoverer are in the same vicinity and are using the same application codes, then they will discover each other's presence.

[0060| Assuming that the UEs do not discover each other and cease their advertising and monitoring functions, the TTL for the first application code will expire, as shown in Figure 5. Starting at that point, the (advertising JE and discovering UE must use a new code of application codes for their respective annunciation and monitoring functions. To maintain continuous annunciation and monitoring functions, there must be a synchronized change of application codes, as indicated in Figure 5. Delays in receiving these codes can cause gaps in the annunciation functions and /or monitoring.

[0061] Various embodiments of the techniques just disclosed and apparatus address this problem by providing for the allocation of multiple application codes at a time (for a given application) to each advertising terminal, with each of the multiple application codes having a validity interval distinct. Also, multiple application codes are provided to monitoring devices, for use as "discovery filters". With this approach, advertising and monitoring devices do not need to ask for a new application code or discovery filter each time an expiration interval expires.

[0062] The exposed techniques allow a seamless transition from using an old application code to using a new application code. This allows for the prevention of signaling storms, caused when multiple wireless devices are requesting new application codes and corresponding discovery filters at the same time. It also allows for a continuous discovery procedure, since each D2D device always has a valid application code that can be used for advertiser filtering and/or discovery for monitoring. In some of the embodiments detailed below, the validity intervals for each of the applications are defined relative to each other - this approach allows the UEs to only run simple timers, since the UEs need not be aware of any absolute time.

[0063] In some embodiments, then, an advertiser UE acquires at least two (or more) application codes from a coordinating network node, rather than just one. According to the approach documented in 3GPP TR 23.703, v 1.1.0, the application codes are provided by a "ProSe function", which can be implemented in a ProSe server or associated with an Evolved Packet Core network of 3GPP (EPC). 3GPP document - 3GPP TR 23.703 can be consulted for further details of the purposes and formats of these application codes, as well as additional parameters associated with these application codes. This ProSe function can thus be adapted according to the techniques now exposed to provide two or more application codes at a time, instead of just one.

[0064] In embodiments of the techniques now exposed, each application code has a different, possibly overlapping, validity interval. In a first alternative, these application codes are used one after the other. Thus, for a specific purpose (application), an advertising UE only advertises with an application code and the UE changes the Application code when the validity time for this application code expires. In a second alternative, the validity times for two application codes may partially overlap, such that the UE advertises with two application codes during a transition phase in which the validity intervals for the two application codes overlap.

[0065] Similarly, a monitoring UE acquires at least two ProSe function discovery filters, instead of just one. (Again. 3GPP TR 23.703 can be consulted for purpose and additional parameters). Each discovery filter has a different validity range, such that the validity ranges for two application codes can be completely different or they can partially overlap. In some embodiments and/or during some intervals, the monitoring UE must always compare with the Discovery filters available for the Application codes advertised for a match. In some embodiments and/or during some intervals, the monitoring UE only compares with the Discovery filter that is active.

[0066] It will be appreciated that the validity intervals may differ and/or be operated differently in advertising and monitoring devices, in some embodiments. Figures 6 and 7 are timing diagrams illustrating two possible approaches to operating expiration intervals for a pair of application codes.

[0067] In the example shown in Figure 6, the validity intervals for access codes AC1 and AC2 in the advertising UE partially overlap, such that the advertising UE broadcasts both codes during a transition period formed by the overlapping validity intervals. The discovery UE (i.e., the monitoring UE), on the other hand, uses access filters AF1 and AF2 to monitor broadcast access codes, in successive non-overlapping time intervals. Note that Figure 6 also shows that the advertiser and discoverer UEs request new access codes/access files, before the end of the second validity interval, thus allowing time to receive one or more new codes before the second validity interval. Of course, it should be appreciated that while Figure 6 illustrates an example in which two codes are used in succession, arrangements in which three or more codes are provided to wireless devices at once are possible, which means that the time between requests can be further extended.

[0068] Figure 7 illustrates another example. In this case, the validity intervals for AC1 and AC2 shortcodes in the advertiser UE do not overlap. As a result, the advertising UE only broadcasts one access code at a time, with the validity interval for the AC2 access code following immediately after the validity interval for the AC1 access code expires.

[0069] The discovery UE (i.e., the monitoring UE), on the other hand, uses access filters AF1 and AF2 to monitor broadcasted access codes, using intervals that overlap such that the discovery UE is monitoring both codes during a transition period formed by the overlapping validity intervals. As Figure 7, Figure 6 also shows that advertiser and discoverer UEs request new access codes/access filters, before the end of the second validity interval, thus allowing time to receive one or more new codes before the second validity interval. . Again, while Figure 7 illustrates an example in which two codes are used in succession, embodiments in which three or more codes are provided to wireless devices at a time are possible, which means that the time between requests can be extended further.

[0070] Figure 8 is a flowchart illustrating the operations performed by the advertiser UE, in an embodiment corresponding to the timeline illustrated in Figure 6.

[0071] The advertiser UE operations as illustrated in Figure 8 are detailed below, as follows:

[0072] 805- The UE requests Application codes (ACn, ACn+1) for the ProSe function. The UE receives ACn and a TTL_ACn which is the TTL for ACn, the UE also receives Application code ACn+1 and Time TTL_ACn+L which is the TTL during ACn+1 and Time T_ACn+l which is the start time of ACn+l related to TTL_ACn, (Note that in other embodiments, the TTL timer for ACn+1 simply starts when TTL_ACn expires, in which case the T_ACn+l parameter is not needed).

[0073] Note: TTL is used as an example to illustrate how the active period is determined for each Access code and Access filter. Other mechanisms such as start and stop time for each AC and AF are also possible.

[0074] 810. Tx timer is started which is fixed to TTL_ACn. Timer Sn+1 is started and is the time when the second advertisement code (ACn+1) is supposed to be used. It is then fixed shorter than TTL_ACn and can be, for example, TTL_ACn - T_ACn+l. The TTL_ACn is the Time to Live for ACn and the T_ACn+l is the start time of ACn+1 related to the TTL_ACn. (In other embodiments, for example those operating according to the timing diagram shown in Figure 7, timer Sn+1 is not needed, as there is no overlapping interval for TTL_ACn and TTL_ACn+l.

[0075] 815. The UE advertises with ACn until an event happens.

[0076] 820. Tx expires, which means it's time to stop advertising with ACn.

[0077] 825. UE stops advertising with ACn Application code.

[0078] 830. When Sn+1 expires, it's time to start using ACn+1.

[0079] 835. Start advertising with ACn+1 also.

[0080] 840. Start Ty timer which is the time until new Application codes will be requested. Ty is set shorter than Tz, and is set to allow time for communication with the ProSe Function to retrieve new Application codes. Tz is the time until the ACn+1 Application code is to expire and is fixed to the received TTL_ACn+l time.

[0081] By setting Ty some randomness can be used to ensure that not all UEs request at the same time.

[0082] The UE announces with ACn+1 until an event happens.

[0083] 845. Ty expires, which means it's time to order new Application codes.

[0084] 850. The UE requests new Application codes for the ProSe function.

[0085] 855. Old Application Code is set to ACn-1 and new Application codes are set to ACn and ACn+1. Timer Tx and Sn+1 are started.

[0086] 860. The UE advertises with Application code ACn-1 and ACn until an event happens.

[0087] 865. When a TTL timer expires, for example Tz is time to stop announcing an Application code.

[0088] 870. Advertise with non-expired Application codes.

[0089] Figure 9 is a flowchart illustrating the operations performed by the monitoring UE, in this case in a mode corresponding to the timeline illustrated in Figure 7. The operations of the monitoring UE as illustrated in Figure 9 are detailed below, as follows:

[0090] 905. The monitoring UE requests to receive Discovery filters from the ProSe function. The UE receives a Dn Discovery filter and a TTL_Dn time. which is the TTL for Dn. The UE also receives Dn+1 Discovery filter and Dn+1 time TTL, which is the TTL for Dn+1 and T_Dn+1 Time. which is the start time of Dn+1 related to TTL_Dn. Dn and Dn+1 correspond to AF1 and AF2 in Figure 6.

[0091] Note: TTL is used as an example to illustrate how the active period (validity interval) is determined for each Access code and Access filter. Other mechanisms for defining validity intervals, such as a start and stop time for each AC and AF, can be used.

|0092] 910. The UE starts timers Tl L_Dn and Sn+1.

[0093] 915. The UE uses the Dn Discovery filter to compare the advertised Application codes to find a possible match.

[0094] 920. The SN+1 timer expires.

|0095] 925. UE starts comparing with Discovery filter Dn+1 likewise.

[0096] 930. The UE starts timer Tw and timer TTL_Dn+l. Timer Tw is the time until new Discovery filters will be requested. Tw is set to allow time for communication with the ProSe Function to retrieve new Discovery filters. By fixing Tw, some randomness can be used to ensure that not all UEs request at the same time.

[0097] 935. TTL_Dn expires, which means the Discovery Dn filter is no longer valid.

[0098] 940. The UE compares with the Discovery filter Dn+1,

[0099] 945. Tw expires, meaning it's time to order new Discovery filters.

[00100] 950. The UE requests new Discovery filters from the ProSe function.

[00101] 955. UE fixed for Discovery filter Dn+1 to Dn-1 and new filters are fixed to Dn and Dn+1. TTL_Dn and Sn+1 timers are started.

[00102] 960. The UE uses the unexpired Discovery filters to compare the advertised Application codes to find a possible match.

[00103] 965. TTL expires, which means that the corresponding Discovery filter has expired.

[00104] 970. The UE uses the unexpired Discovery filters to compare with the advertised Application codes to find a possible match.

[00105] Figure 10 is a copy of the Roaming Reference Architecture illustrated in 3GPP TR 23703. PC3 is the reference point used to request and receive Application codes for an advertising UE and request and receive Discovery filters for a monitoring UE. PC5 is the reference point used for annunciation and monitoring. It will be appreciated that while this provides an example context for implementing the techniques described here, the techniques can be applied to networks having architectures other than those shown in Figure 10.

[00106] Due to the foregoing detailed examples of application code operating in the context of D2D devices operating on or in association with an LTE network, it should be appreciated that these techniques can be seen and applied more generally. Figures 11 and 12 illustrate generalized processes that can be performed on wireless devices acting as an advertising device and monitoring device, respectively. It should be noted that a wireless device can act as both in some cases, whether at the same time or at different times.

[00107] Figure 11 is a process flowchart illustrating a method that can be implemented in a wireless device configured for operation in a wireless communication network and further configured for device-to-device communication with one or more other wireless devices. As seen at block 1120, the method includes receiving, from a coordination node, first and second access codes, here called application codes, and associated timing information. The associated timing information defines respective first and second validity intervals for the first and second application codes, such that the first and second validity intervals are at least partially non-overlapping. The coordination node can be a ProSe server in or associated with an LTE network, for example. It should be noted that while Figure 11 illustrates a process in which two application codes and associated timing information are received, three or more application codes and associated timing information may be sent in other embodiments.

[00108] In some embodiments, the first and second application codes are received in response to a request from the announcing device. This is shown at block 1110, which indicates that the advertising device, before receiving the first and second application codes and associated timing information, sends a first application code request to the coordination node, for example, over the communication network. wireless. Application codes and timing information are received in response to this request.

[00109] As shown at blocks 1130 and 1140, subsequent to receiving the first and second application codes and associated timing information, the advertising device transmits, during the first validity interval, one or more discovery messages that include or are based on in the first application code, and transmits, during the second validity interval, one or more discovery messages that include or are based on the second application code. In some embodiments, the associated timing information defines first and second validity intervals that are not completely overlapping, such that the first and second validity intervals are consecutive but not overlapping. In others, the intervals may partially overlap, such that the advertising device transmits one or more discovery messages based on each of the first and second application codes during an overlapping transition interval.

[00110] The associated timing information can define the first and second validity intervals in several different ways. For example, the associated timing information may include first and second time-to-live values, in some embodiments, the first and second time-to-live values indicating respective durations of the first and second validity intervals. In some embodiments, the second validity interval begins at the end of the first validity interval. In others, the associated timing information includes a start time value indicating a start time for the second validity interval such that the second validity interval begins before the end of the first validity interval.

[00111] Once the final validity interval expires, new application codes are required. Thus, as shown at block 1150, a new application code request is sent to the coordination node. In some embodiments, this is done before the end of the second validity interval, to allow time to receive new access codes before the second validity interval expires. The illustrated method can thus be repeated, for example, such that a third (and fourth, fifth, etc.) application code and associated timing information is received, where the associated timing information defining in a third validity time for the third access code, such that the third expiration time is non-overlapping at least partially with both the first and second expiration times, and one or more discovery messages that include or are based on the third application code are transmitted, during the third validity interval.

[00112] Figure 12 is a process flowchart illustrating a corresponding method executed on a monitoring device. It should be appreciated that the illustrated operations correspond closely to those shown in Figure 11, except that the monitoring device monitors (i.e., "listens" to) discovery messages containing a match code during the first and second validity intervals, in place of broadcasting announcement messages.

[00113] As shown at block 1220, the illustrated method includes receiving first and second discovery filters and associated timing information. In some embodiments, this may be in response to a discovery filter request sent by the wireless monitoring device, as shown at block 1210. Associated timing information defines respective first and second validity intervals for the first and second discovery filters. discovery, such that the first and second validity intervals are at least partially non-overlapping. The method further includes, subsequent to receiving the first and second discovery filters and associated timing information, monitoring, during the first validity interval, a discovery message that includes or is based on the first discovery filter. This is shown at block 1230. Then, as shown at block 1240, the wireless monitoring device monitors, during the second validity interval, for a discovery message that includes or is based on the second discovery filter.

[00114] In some embodiments, the associated timing information includes first and second time-to-live values, the first and second time-to-live values indicating respective durations of the first and second validity intervals. In some of these prior embodiments, the second validity interval begins at the end of the first validity interval. In others, the associated timing information includes a start time value indicating a start time for the second validity interval such that the second validity interval begins before the end of the first validity interval.

[00115] As shown at block 1250, the monitoring device may also send a request for additional Discovery Filters; this can be done before the second validity interval expires, so that new discovery filters are received in sufficient time to establish subsequent validity intervals without interruption. Thus, in some embodiments, the wireless device, subsequent to receiving the first and second discovery filters and associated timing information, but before the end of the second validity interval: receives a third discovery filter and associated timing information defining a third validity time for the additional discovery filter, such that the third validity time is at least partially non-overlapping with both the first and second validity times, and monitors, during the third validity interval, a discovery message that includes or is based on the third discovery filter. It will be appreciated that these techniques can be repeated as needed.

[00116] Figure 13 illustrates a process flow for a method implemented in one or more network nodes adapted to provide device-to-device related services to wireless devices operating in a wireless communication network. The network node or nodes are responsible for distributing application codes to advertiser wireless devices. Thus, as shown at block 1310, the method includes receiving an application code request from a first wireless device.

[00117] As shown at block 1320, the method continues with sending first and second application codes and associated timing information to the first wireless device. As discussed above, the associated timing information defines respective first and second validity intervals for the first and second application codes, such that the first and second validity intervals for the first and second application codes are at least partially non-overlapping.

[00118] In some embodiments, the same network node or nodes may also be responsible for distributing discovery filter codes to monitoring devices. In these embodiments, the method may further include, as shown at block 1330, receiving a discovery filter request from a second wireless device. As shown at block 1340, the node or nodes then send first and second discovery filters and associated timing information to the second wireless device. Once again. the associated timing information defines respective first and second validity intervals for the first and second discovery filters, such that the first and second validity intervals for the first and second discovery filters are at least partially non-overlapping. The first and second discovery filters may correspond to the first and second application codes, respectively, such that monitoring by the second wireless device using the first and second discovery filters will detect discovery messages based on the first and second application codes, respectively.

[00119] Embodiments of the techniques disclosed now include the various methods described above, including the methods illustrated in the process flowcharts of Figures 11, 12 and 13, as well as variants thereof. Other embodiments include mobile terminal apparatus and network node apparatus configured to perform one or more of these methods. In some embodiments of the invention, processing circuits, such as processing circuit 210 in Figure 2 or processing circuit 10, 20, 30 in Figure 3, are configured to perform one or more of the techniques described in detail above. Also, other embodiments may include mobile terminals and network node apparatus that include one or more such processing circuits. In some cases, these processing circuits are configured with appropriate program code, stored in one or more memory devices suitable for implementing one or more of the techniques described herein. Of course, it will be appreciated that not all steps in these techniques are necessarily performed on a single microprocessor or even a single module.

[00120] As noted above, it should be appreciated that the processing circuit, when configured with appropriate program code, can be understood to include multiple "functional modules", where each module includes program code to perform the corresponding function, when executed by an appropriate processor. Figure 14 illustrates an example arrangement 1400, in which the functionality described here is visualized in terms of functional modules. The illustrated arrangement 1400 may be understood to represent a processing circuit configured with corresponding program code, or a computer-readable medium including modules of program code stored therein or thereafter.

[00121] The arrangement 1400 shown in Figure 14 includes a receiver module 1410, a transmitter module 1420, a monitoring module 1430, and a sending module 1440. Each of these modules is adapted to perform one or more of the corresponding functions detailed above . For example, in some embodiments, the receiver module 1410 is for receiving, from a coordination node in a wireless communication network, first and second application codes and associated timing information, the associated timing information defining respective first and second validity intervals for the first and second application code, such that the first and second validity intervals are at least partially non-overlapping. Transmitter module 1420 is for subsequently transmitting, during the first validity interval, one or more discovery messages that include or are based on the first application code, and transmitting, during the second validity interval, one or more discovery messages that include or are based on the second application code. In some of these embodiments, the sending module 1440 is for sending a first application code request to the coordination node over the wireless communication network, wherein the first and second application codes and associated timing information are received in response. to the first application code request. The various variations described above with respect to the description of Figure 11 are equally applicable to these exemplary embodiments.

[00122] In some of these and in some other example embodiments, the receiver module 1410 is for receiving first and second discovery filters and associated timing information, the associated timing information defining respective first and second validity intervals for the first and second second discovery filters, such that the first and second validity ranges are at least partially non-overlapping. Monitoring module 1430 is for subsequently monitoring, during the first validity interval, a discovery message that includes or is based on the first discovery filter, and monitoring, during the second validity interval, a discovery message that includes or is based on the first discovery filter. based on the second discovery filter. In some of these embodiments, the dispatch module 1440 is for sending requests for discovery filters to the coordination node over the wireless communication network. The various variations described above with respect to the description of Figure 12 are equally applicable to these exemplary embodiments.

[00123] It will be appreciated by the person of skill in the art that various modifications can be made to the embodiments described above without departing from the scope of the present invention. For example, although embodiments of the present invention have been described with examples that reference a communication system compliant with the LTE standards specified by 3GPP, it should be noted that the presented solutions can be equally well applicable to other networks. The specific embodiments described above, therefore, should be considered exemplary rather than limiting the scope of the invention. Because it is not possible, of course, to describe every conceivable combination of components or techniques, those skilled in the art will appreciate that the present invention can be implemented in ways other than those specifically disclosed herein, without departing from the essential features of the invention. The present embodiments will therefore be considered in all respects as illustrative and not restrictive.

[00124] In the present description of various embodiments of present inventive concepts, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of present inventive concepts. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by one of ordinary skill in the art to which the present inventive concepts belong. It will further be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense as expressly defined. here.

[00125] As used herein, the singular forms "a", and "the" are intended to include the plural forms equally, unless the context clearly indicates otherwise. Well-known functions or constructs may not be described in detail for brevity and/or clarity. The term "and/or" includes any and all combinations of one or more of the associated listed items.

[00126] It will be understood that although the terms first, second, third, etc., may be used herein to describe various elements/operations, these elements/operations should not be limited by these terms. These terms are used only to distinguish one element/operation from another element/operation. Thus, a first element/operation in some embodiments could be called a second element/operation in other embodiments without departing from the present inventive concept teachings. The same reference numerals or the same reference designators denote the same or similar elements throughout the specification.

[00127] As used herein, the terms "comprises", "comprising", "includes", "includes", "including", "includes", "have", "has", "having", or variants thereof are in open, and include one or more declared features, integers, elements, steps, components, or functions, but does not preclude the presence or addition of one or more other features, integers, elements, steps, components, functions, or groups thereof. Furthermore, as used herein, the common abbreviation "for example", which derives from the Latin phrase "exempli gratia", may be used to introduce or specify a general example or examples of a previously mentioned item, and is not intended to be limiting of such item. The common abbreviation "i.e"., which derives from the Latin phrase "id est", can be used to specify a particular item in a more general recitation.

[00128] Example embodiments have been described herein with reference to block diagrams and/or flowchart illustrations of computer-implemented methods, apparatus (systems and/or devices) and/or computer program products. It is understood that a block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, may be implemented by computer program instructions that are executed by one or more computer circuits. . These computer program instructions may be provided to a processor circuit of a general purpose computer circuit, special purpose computer circuit, and/or other programmable data processing circuit to produce a machine such that the instructions it performed by the computer's processor and/or other programmable data processing apparatus, transform and control transistors, values stored in memory locations, and other hardware components within such circuits to implement the functions/acts specified in the block diagrams and/or or flowchart block or blocks, and thereby create means (functionality) and/or structure to implement the functions/acts specified in the block diagrams and/or flowchart blocks.

[00129] These computer program instructions may also be stored on a tangible computer-readable medium, which can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored on the computer-readable medium computer produce an article of manufacture including instructions that implement the functions/acts specified in the block diagrams and/or block or flowchart blocks. Accordingly, embodiments of the present inventive concepts may be embodied in hardware and/or in software (including firmware, resident software, microcode, etc.) running on a processor such as a digital signal processor, which may be collectively called a "circuit" , a "module", or variants thereof.

[00130] It should also be noted that in some alternate implementations, functions/acts noted in blocks may occur outside of the order noted in flowcharts. For example, two blocks shown in succession may actually run substantially simultaneously, or the blocks may sometimes run in reverse order, depending on the functionality/acts involved. Furthermore, the functionality of a given block of the flowcharts and/or block diagrams may be separated into multiple blocks and/or the functionality of two or more blocks of the flowcharts and/or block diagrams may be at least partially integrated. Finally, other blocks can be added/inserted between the blocks that are illustrated, and/or blocks/operations can be omitted without departing from the extension of inventive concepts. Furthermore, although some of the diagrams include arrows on communication paths to show a primary direction of communication, it is to be understood that communication can occur in the opposite direction to the arrows depicted.

[00131] Many variations and modifications can be made to the embodiments without departing substantially from the principles of the present inventive concepts. All such variations and modifications are intended to be included within the scope of the present inventive concepts herein. Accordingly, the foregoing subject matter is to be considered illustrative, not restrictive, and the attached examples of embodiments are intended to cover all such modifications, enhancements, and other embodiments, which fall within the spirit and scope of the present inventive concepts. Thus, to the fullest extent permitted by law, the scope of the present inventive concepts is to be determined by the broadest permissible interpretation of the present description, and shall not be restricted or limited by the foregoing detailed description.

Claims (28)

1. Method, in a wireless device configured for operation in a wireless communication network and further configured for device-to-device communication with one or more other wireless devices, the method comprising: receiving (1120), from a coordination, first and second application codes at a time, and associated timing information, the associated timing information defining respective first and second validity intervals for the first and second application code, such that the first and second validity intervals are not overlapping at least partially; and, subsequent to receiving the first and second application codes and associated timing information, transmitting (1130), during the first validity interval, one or more discovery messages that include or are based on the first application code, and transmitting ( 1140), during the second validity interval, one or more discovery messages that include or are based on the second application code, characterized in that the associated timing information defines first and second validity intervals that do not completely overlap or where the first validity interval begins before the start of the second validity interval and ends before the end of the second validity interval, and wherein the first and second validity intervals are defined such that the wireless device transmits discovery messages that include, or are based on each of the first and second application codes during a transitional phase in which the validity ranges for the two application codes overlap. 2. Method according to claim 1, characterized in that it further comprises, before receiving the first and second application codes and associated timing information, sending (1110) a first application code request to the coordination node , over the wireless communication network, wherein the first and second application codes and associated timing information are received in response to the first application code request. 3. Method according to claim 1 or 2, characterized in that the associated timing information comprises first and second time-to-live values, the first and second time-to-live values indicating respective durations of the first and second validity intervals. 4. Method according to claim 3, characterized in that the second validity interval starts at the end of the first validity interval. 5. Method according to claim 3, characterized in that the associated timing information comprises a start time value indicating a start time for the second validity interval, such that the second validity interval starts before the end of the first validity interval. 6. Method according to any one of claims 1 to 5, characterized in that it additionally comprises, subsequent to receiving the first and second application codes and associated timing information, but before the end of the second validity interval: receiving a third application code and associated timing information defining a third validity time for the third application code such that the third validity time is at least partially non-overlapping with both the first and second validity intervals, and transmitting, during the third validity interval, one or more discovery messages that include or are based on the third application code. 7. Method, in a wireless device configured for operation in a wireless communication network and further configured for device-to-device communication with one or more other wireless devices, the method comprising: receiving (1220) first and second data filters discovery at a time, and associated timing information, the associated timing information defining respective first and second validity intervals for the first and second discovery filters, such that the first and second validity intervals are at least partially non-overlapping; and, subsequent to receiving the first and second discovery filters and associated timing information, monitor (1230), during the first validity interval, a discovery message that includes or is based on the first discovery filter, and monitor (1240) , during the second validity interval, a discovery message that includes or is based on the second discovery filter, characterized in that the associated timing information defines first and second validity intervals that do not completely overlap or in which the first validity interval validity period begins before the start of the second validity interval and ends before the end of the second validity interval and wherein the first and second validity intervals are defined such that the wireless device monitors for both application codes during a period of transition between transition intervals. 8. Method according to claim 7, characterized in that the associated timing information comprises first and second time-to-live values, the first and second time-to-live values indicating respective durations of the first and second validity intervals. 9. Method according to claim 8, characterized in that the second validity interval starts at the end of the first validity interval. 10. Method according to claim 9, characterized in that the associated timing information comprises a start time value indicating a start time for the second validity interval, such that the second validity interval starts before the end of the first validity interval. 11. Method according to any one of claims 7 to 10, characterized in that it additionally comprises, subsequent to receiving the first and second discovery filters and associated timing information, but before the end of the second validity interval: receiving a third discovery filter and associated timing information defining a third expiration time for the additional discovery filter, such that the third expiration time is at least partially non-overlapping with both the first and second expiration intervals, and monitoring, during the third validity interval, a discovery message that includes or is based on the third discovery filter. 12. A wireless device (200) comprising radio circuitry (220) configured for communication with a wide area wireless network and for device-to-device communication with one or more other wireless devices and further comprising processing circuitry (210) configured to control the radio circuit (220) and to: receive from a coordination node, using the radio circuit (220), first and second application codes at a time, and associated timing information, the information associated timing defining respective first and second validity intervals for the first and second application codes such that the first and second validity intervals are at least partially non-overlapping; and, subsequent to receiving the first and second application codes and associated timing information, controlling radio circuitry (220) to transmit, during the first validity interval, one or more discovery messages that include or are based on the first code application code, and transmitting, during the second validity interval, one or more discovery messages that include or are based on the second application code, characterized in that the associated timing information defines first and second validity intervals that do not completely overlap or wherein the first validity interval begins before the start of the second validity interval and ends before the end of the second validity interval, and wherein the first and second validity intervals are defined such that the wireless device transmits discovery messages that include, or are based on, each of the first and second application codes during a transition phase in which the validity ranges for the two application codes overlap. 13. Wireless device (200) according to claim 12, characterized in that the processing circuit (210) is further configured to, before receiving the first and second application codes and associated timing information, send a first application code request to the coordination node over the wireless communication network, wherein the first and second application codes and associated timing information are received in response to the first application code request. 14. A wireless device (200) according to claim 12 or 13, characterized in that the associated timing information comprises first and second time-to-live values, the first and second time-to-live values indicating respective durations of the first and second validity intervals. 15. Wireless device (200) according to claim 14, characterized in that the second validity interval starts at the end of the first validity interval. 16. Wireless device (200) according to claim 15, characterized in that the associated timing information comprises a start time value indicating a start time for the second validity interval, such that the second validity interval validity starts before the end of the first validity interval. 17. Wireless device (200) according to any one of claims 12 to 16, characterized in that the processing circuit (210) is further configured to, subsequent to receiving the first and second application codes and timing information associated but before the end of the second validity interval: receiving a third application code and associated timing information defining a third validity time for the additional application code, such that the third validity time is at least partially non-overlapping with both of the first and second validity times, and controlling radio circuitry (220) to transmit, during the third validity interval, one or more discovery messages that include or are based on the third application code. 18. A wireless device (200) comprising radio circuitry (220) configured for communication with a wide area wireless network and for device-to-device communication with one or more other wireless devices and further comprising processing circuitry (210) configured to control the radio circuit (220) and to: receive first and second discovery filters at a time, and associated timing information, the associated timing information defining respective first and second validity intervals for the first and second second discovery filters, such that the first and second validity ranges are at least partially non-overlapping; and, subsequent to receiving the first and second discovery filters and associated timing information, monitoring, during the first validity interval, a discovery message that includes or is based on the first discovery filter, and monitoring, during the second validity interval, validity means a discovery message that includes or is based on the second discovery filter characterized in that the associated timing information defines first and second validity intervals that do not completely overlap or in which the first validity interval begins before the start of the second validity interval and ends before the end of the second validity interval and wherein the first and second validity intervals are defined such that the wireless device monitors for both application codes during a transition period between the transition intervals. 19. Wireless device (200) according to claim 18, characterized in that the associated timing information comprises first and second time-to-live values, the first and second time-to-live values indicating respective durations of the first and according to validity intervals. 20. Wireless device (200) according to claim 19, characterized in that the second validity interval starts at the end of the first validity interval. 21. Wireless device (200) according to claim 19, characterized in that the associated timing information comprises a start time value indicating a start time for the second validity interval, such that the second validity interval validity starts before the end of the first validity interval. 22. Wireless device (200) according to any one of claims 19 to 21, characterized in that the processing circuit (210) is further configured to, subsequent to receiving the first and second discovery filters and timing information associated but before the end of the second validity interval: receiving a third discovery filter and associated timing information defining a third validity time for the additional discovery filter such that the third validity time is at least partially non-overlapping with both of the first and second validity intervals, and monitor, during the third validity interval, a discovery message that includes or is based on the third discovery filter. 23. Method, in one or more network nodes adapted to provide device-to-device related services to wireless devices operating in a wireless communication network, the method comprising: receiving (1310) an application code request from a first wireless device; and sending (1320) first and second application codes at a time, and associated timing information to the first wireless device, the associated timing information defining respective first and second validity intervals for the first and second application codes, such that the first and second validity intervals for the first and second application codes are at least partially non-overlapping, characterized in that the associated timing information defines first and second validity intervals not completely overlapping or in which the first validity interval validity begins before the beginning of the second validity interval and ends before the end of the second validity interval and wherein the first and second validity intervals are defined such that the wireless device transmits one or more discovery messages based on each other of the first and second application codes, during an overlapping transition interval between the validity intervals. The method of claim 23, further comprising: receiving (1330) a discovery filter request from a second wireless device; and sending (1340) first and second discovery filters and associated timing information to the second wireless device, the associated timing information defining respective first and second validity intervals for the first and second discovery filters, such that the first and second discovery filters second validity intervals for the first and second discovery filters are at least partially non-overlapping. 25. Method according to claim 24, characterized in that the first and second discovery filters correspond to the first and second application codes, respectively, such that monitoring by the second wireless device using the first and second discovery filters will detect discovery messages based on the first and second application codes, respectively. 26. Network node (1) adapted to provide device-to-device related services to wireless devices operating in a wireless communication network, the network node (1) comprising a communication interface (40) configured for communication with a or more wireless devices and further comprises a processing circuit (10, 20, 30) configured to control the communication interface and to: receive an application code request from a first wireless device; and sending first and second application codes at a time, and associated timing information to the first wireless device, the associated timing information defining respective first and second validity intervals for the first and second application codes, such that the first and second validity intervals for the first and second application codes are at least partially non-overlapping characterized in that the associated timing information defines first and second validity intervals not completely overlapping or in which the first validity interval begins before the beginning of the second validity interval and ending before the end of the second validity interval and wherein the first and second validity intervals are defined such that the wireless device transmits one or more discovery messages based on each of the first and second validity intervals application codes, during an overlapping transition interval between validity intervals. Network node (1) according to claim 26, characterized in that the processing circuit (10, 20, 30) is further configured to: receive a discovery filter request from a second wireless device; and sending first and second discovery filters and associated timing information to the second wireless device, the associated timing information defining respective first and second validity intervals for the first and second discovery filters, such that the first and second discovery intervals validity for the first and second discovery filters are at least partially non-overlapping. 28. Network node (1) according to claim 27, characterized in that the first and second discovery filters correspond to the first and second application codes, respectively, such that monitoring by the second wireless device using the first and second discovery filters will detect discovery messages based on the first and second application codes, respectively.