Patent Description:
The current cellular Long Term Evolution (LTE) standard supports flexible bandwidth (BW), from <NUM> up to <NUM>, and even wider bandwidths using carrier aggregation techniques. In order for a wireless device-e.g., a "UE" in 3GPP parlance-to connect to a network (NW) node, such as an eNodeB or other base station, the wireless device must determine the cell carrier frequency as well as the system bandwidth to use. Furthermore, in current LTE standards there is a requirement that the NW node and the wireless device support and connect using the same system BW. Hence, the wireless device must search for relevant control messages over the entire system BW of the NW.

For the upcoming new radio-access technology in <NUM>, denoted NR herein, a more generic approach is desirable w. t the system bandwidths of respective nodes. NR should support multiple types of wireless devices. A range of device types includes, for example, high-end Mobile Broadband (MBB) devices capable of supporting system BWs up to several GHz, down to low-cost, low-power Machine Type Communication (MTC) devices, which may support BWs of <NUM> or perhaps a few MHz.

Hence, one of the capabilities desired NR systems is flexibility in allocating "scheduling" BWs to respective wireless device. Here, scheduling BW is the BW determined and signalled by the network node to the wireless device such that the wireless device may apply a receive BW in which it may search for a control channel. In particular, in contrast to prior releases of LTE (and other, earlier-generation network standards), NR systems should have the ability to allocate a "scheduling" bandwidth to any given device that lies anywhere within the overall system BW configured for the supporting NW node. The allocated scheduling bandwidth may equal or be less than the radio receiver BW supported by the device.

eMTC is part of Release <NUM> by the 3GPP and, among other things, provides for lower bandwidths in the uplink and downlink, lower data rates and reduced transmit power, all benefitting at least certain types of MTC device. While the eMTC enhancements allow for an MTC device to operate on a BW smaller than the system BW of the supporting NW node it connects with, the approach lacks the flexibility needed for NR systems because it is based on using a fixed <NUM> BW.

Hence, it is recognized herein that there remains a need for a method and apparatus to provide the signalling needed between NR networks and the devices operating in them, to support flexible scheduling BW allocations.

<CIT> describes receiving controlling signaling in a first bandwidth, receiving a signaling message indicating a second bandwidth, receiving a first DCI format size, the first DCI format size being based on the first bandwidth, and receiving a second control message using a second DCI format size, the second size being based on the second bandwidth.

3GPP TSG RAN WG1 Meeting #<NUM>, R1-<NUM> describes mechanisms of bandwidth adaption in NR together with handling of DCI in bandwidth adaption. It seems to be described that when more resources are needed, the gNB can indicate to the UE to switch to another wider bandwidth dynamically or semi-statically.

<CIT> describes a method for adjusting a size of an information bit used in a control channel by performing blind decoding in a search space allocated in a terminal to search for a PDCCH and receiving the PDCCH including DCI having a size adjusted in the search space. The size of the DCI can be adjusted by considering a bandwidth allocated in the terminal, a transmission mode of a component carrier allocated in the terminal and the number of antennas of the terminal.

The invention is based on the understanding that power may be saved by avoiding to monitor a wider bandwidth of downlink control signal than necessary.

Throughout the description, reference is made to the appended drawings.

<FIG> depicts an example of a wireless communication network <NUM> that is configured to communicatively couple to a wireless device <NUM>, to provide one or more communication services to the wireless device <NUM>. By way of example, the wireless communication network <NUM> ("network <NUM>") provides Internet or other packet-data connectivity for the wireless device <NUM>. More particularly, the network <NUM> and the wireless device <NUM> operate according to the flexible scheduling bandwidth allocations and power-efficient operations described herein.

According to the simplified depiction given in <FIG>, the network <NUM> includes a Radio Access Network (RAN) <NUM> and associated network (NW) infrastructure <NUM>. The NW infrastructure includes, for example, data processing, switching, and storage functions, along with providing mobility management and routing interfaces into and out of the RAN <NUM>. The network infrastructure <NUM> may communicatively couple to a cloud execution environment <NUM>-e.g., providing one or more Network Functions (NFs) or application services-and may also couple to one or more data centres <NUM>. Further, there may be more than one RAN <NUM>, and more than one type of Radio Access Technology (RAT) involved.

In some examples, the network <NUM> comprises a so-called "<NUM>" network, also referred to herein as a "NR" network or system, where "NR" denotes "New Radio. " According to one contemplated implementation, the network <NUM> represents an evolution of LTE for existing spectrum in combination with new radio access technologies that primarily target new spectrum. Among its key technology components, the network <NUM> in a <NUM> implementation includes access/backhaul integration, device-to-device communication, flexible duplex, flexible spectrum usage, multi-antenna transmission, ultra-lean design, and user/control data separation. Here, ultra-lean design refers to the minimization of any transmissions not directly related to the delivery of user data, and the RAN <NUM> may be configured to rely heavily on beamforming for the delivery of user data via one or more narrow, dynamically-allocable antenna beams.

Other points of flexibility and breadth apply to the wireless device <NUM> ("device <NUM>"). Firstly, the network <NUM> may support potentially many devices <NUM>, and the various devices <NUM> may be of different types and may be engaged in different types of communication services. For example, a device <NUM> configured for Mobile BroadBand (MBB) services may be used by a person to access movies, music, and other multimedia content delivered through the network <NUM>. On the other hand, a device <NUM> configured for embedded operation may not include any user interface, and may engage only in low-power, low-rate Machine Type Communication (MTC) transmissions or receptions. Thus, by way of example rather than limitation, the device <NUM> may be a smartphone, a feature phone, a sensor, an actuator, a wireless modem or other wireless network adaptor, a laptop computer, a tablet or other mobile computing device, or essentially any other wireless communication apparatus configured for accessing the network <NUM> and operating according to any one or more of the RATs supported by the network <NUM>. Still further, the device <NUM> may be a mobile device or may be installed or operated in a fixed location.

<FIG> depicts example implementation details for the device <NUM> and for a network node <NUM> that is configured to support network-side aspects of the teachings herein. The network node <NUM> includes communication interface circuitry <NUM>, which in turn includes radio frequency transceiver circuitry <NUM>-i.e., one or more radio frequency transmitter and receiver circuits-for wireless communicating with one or more devices <NUM>, according to one or more RATs. Further, in at least one embodiment, the communication interface circuitry <NUM> includes one or more network interfaces-e.g., Ethernet or other intra-node interface-for communication with one or more other nodes in the network <NUM>, and may not have radio frequency circuitry. In such embodiments, the network node <NUM> may communicate indirectly with the device <NUM>, e.g., through another node that has radio frequency circuitry.

The network node <NUM> also includes processing circuitry <NUM> that is operatively associated with the communication circuitry <NUM>. The processing circuitry <NUM> comprises programmed circuitry or fixed circuitry, or a combination of programmed and fixed circuitry. In an example embodiment, the processing circuitry <NUM> comprises one or more microprocessors, Digital Signal Processors (DSPs), Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), or other digital processing circuits.

In at least one embodiment, the processing circuitry <NUM> is configured at least in part based on its execution of computer instructions included in one or more computer programs <NUM> stored in storage <NUM> in the network node <NUM>. The storage <NUM> may also store one or more items of configuration data <NUM> associated with operation of the network node <NUM> according to the teachings herein. The storage <NUM> comprises, for example, one or more types of computer-readable media, such as Solid State Disk (SSD), FLASH, DRAM, SRAM, etc. In one embodiment, the storage <NUM> provides for long-term storage of the computer program(s) <NUM>, and further provides working memory for operation of the processing circuitry <NUM>.

<FIG> also provides example implementation details for the device <NUM>. The device <NUM> includes communication interface circuitry <NUM>, which in turn includes radio frequency transceiver circuitry <NUM>-i.e., one or more radio frequency transmitter and receiver circuits-for wireless communicating with the network <NUM>, according to one or more RATs.

The device <NUM> also includes processing circuitry <NUM> that is operatively associated with the communication circuitry <NUM>. The processing circuitry <NUM> comprises programmed circuitry or fixed circuitry, or a combination of programmed and fixed circuitry. In an example embodiment, the processing circuitry <NUM> comprises one or more microprocessors, Digital Signal Processors (DSPs), Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), or other digital processing circuits.

In at least one embodiment, the processing circuitry <NUM> is configured at least in part based on its execution of computer instructions included in one or more computer programs <NUM> stored in storage <NUM> in the device <NUM>. The storage <NUM> may also store one or more items of configuration data <NUM> associated with operation of the device <NUM> according to the teachings herein. The storage <NUM> comprises, for example, one or more types of computer-readable media, such as Solid State Disk (SSD), FLASH, DRAM, SRAM, etc. In one embodiment, the storage <NUM> provides for long-term storage of the computer program(s) <NUM>, and further provides working memory for operation of the processing circuitry <NUM>.

With the above in mind, the network node <NUM> may be configured to send or initiate the sending of signalling indicating or configuring the scheduling bandwidth (BW) for given wireless devices <NUM>. The network node <NUM> may further be configured to signal changes in the scheduling BW, and to indicate, for example, first and second receiver BWs to be used by a device <NUM> for signal reception. As an example, the network node <NUM> indicates a first receiver BW to be used by a device <NUM>, and then subsequently indicates a second receiver BW to be used by the device <NUM>. The indications may be explicit and/or implicit, as will be discussed below. Furthermore, as also will be discussed below, the BW used by the UE for monitoring control signals from the network node is intended to be adapted accordingly to avoid consuming unnecessary power by monitoring a too wide BW.

Still further, the network node <NUM>, or another entity in the network, may be configured to determine timer parameters needed for controlling the BW configuration changes at the device <NUM>, e.g., for changing from the first receiver BW to the second receiver BW, or from the second receiver BW back to the first receiver BW. Here, the terms "receiver BW" and "scheduling BW" are used. The scheduling BW is set by the NW node and signalled to the wireless device. The wireless device sets its receiver BW based on the scheduling BW, e.g. to the same BW. These BWs may be denoted as a number of resource blocks which the wireless device scans for a control channel. It is also contemplated to configure or otherwise indicate timer parameters to be used for receiver BW configuration changes at the device <NUM> when DRX mode is active.

Complementing these aspects of the disclosed teachings, the device <NUM> may be configured to use the configuration parameters to reduce receiver power consumption. In particular, the device <NUM> reduces its receiver power consumption by only using sufficient receiver BW for reception of data and/or Layer <NUM>/Layer <NUM> control, based on the current user scenario and device needs. Here, a user scenario may be that one or more communication sessions are ongoing, the nature of communication session(s), etc. The nature of a communication session may comprise size, e.g. whether it comprises only a notification or if it comprises a media stream, latency requirements, differentiation between types of transmitted information, etc. Device needs may for example comprise power consumption, processing power, RF capabilities, battery status, etc..

In one example scenario, the device <NUM> operates with a first receiver BW and then reconfigures to a wider, second receiver BW, e.g., responsive to signalling from the network <NUM>. The device <NUM> may be reconfigured to the second BW to facilitate the transmission of a larger amount of data or higher-rate data to the device <NUM>, as compared to what could be supported using the first receiver BW. Advantageously, when operation returns to data traffic according to the first BW after a transmission on the second BW is that some packets, which may arrive slightly later, e.g. due to some media protocol, than the data requiring the second BW, can be handled when transition has been made to operate at the first BW, and thus at lower power or capacity consumption. In particular, these packets may be handled before a DRX timer elapses, wherein the limited capacity when operating with the first BW is proper for that handling. Furthermore, if both high-demand sessions and low-demand sessions are performed simultaneously, transition to operation of the low-demand sessions will be smoother. An advantage is further that resources are saved when transmissions are limited in both BW and time.

Given the general mechanisms of using different BWs and signalling related to that, as demonstrated above, this disclosure will now focus on BW used for monitoring and searching for a control channel. An aim is to be able to do monitoring and search using a smaller BW receiver, and thereby reduce power consumption, when that is feasible in view of required operation. That is, a larger BW reception for the monitoring and search may be used when that is beneficial, but is avoided otherwise. To accomplish this, there is a need for an approach of adapting control signalling format.

Consider a UE (device, smartphone, IoT/MTC device, modem, laptop, tablet computer, etc.) is operating in a mode where the UE can be configured with at least a first narrowband downlink (DL) monitoring BW and a second wideband DL monitoring BW. In the configured BW, the UE monitors for reception of control and data information, and within a control channel a Downlink Control Indicator (DCI) may be transmitted to the UE, where the DCI includes information relevant for further DL processing of data, such as resource block (RB) allocation in Physical Downlink Shared Channel (PDSCH), Multiple-Input-Multiple-Output (MIMO) state, hybrid-ARQ (Automatic Repeat reQuest) parameters, modulation and coding scheme (MCS), etc., as well as uplink (UL) transmission of data, such as RB allocation, MIMO state, hybrid-ARQ parameters, MCS, etc. An applied DCI format is one of a set of allowed DCI formats, indicating payload size, content, usage, etc., which set may be different depending on the configured DL monitoring BW, and may be defined by a standard associated to the applied communication, i.e. related to the used Radio Access Technology, for instance the NR standard. From these limitations, an implicit signalling from a network node to a UE may provide a very slim approach of signalling due to the very limited overhead. That is, a network node of an access network, where the network node is serving the UE, configures a DL scheduling (or monitoring) BW to be used. This may for example be made based on service to be provided, on amount of data present in transmit data buffer, on traffic history, on data type, etc. Based on the configured DL BW, the network node determines a set of DCI formats which is feasible to use. When data is to be sent to the UE, the network node transmits control information to the UE using one of the DCI formats of the determined set such that the UE then can receive/transmit data according to the DCI setting. Ways of accomplishing these approaches for the UE and the network node will be demonstrated with reference to <FIG> and <FIG> below.

<FIG> is a flow chart schematically illustrating a method of a wireless device. The method comprises determining <NUM> a bandwidth for monitoring a downlink control signal. The determining <NUM> of the bandwidth for monitoring may be based on a previous or anterior used DCI. For example, the previous or anterior DCI may comprise explicit information about bandwidth to be used in consecutive transmission, wherein the wireless device will know which bandwidth to apply. Another example is that the determining of the bandwidth may be implicitly assumed, when no other information is available indicating the contrary, to be a bandwidth associated with the previous or anterior DCI, i.e. a bandwidth suitable or used therewith. The determining of the bandwidth may also include resetting a timer when a resource allocation reaches an allocation threshold, wherein the allocation threshold may be that a certain time has passed without indications on use of the wider BW. Thus, a timer may be set at each indication that the wider BW is applied, and when the timer elapses the resource allocation is considered to go below the allocation threshold, and the UE returns to monitoring a narrower BW. Here, for the sake of brevity, the terms BW and bandwidth are used for downlink (DL) monitoring BW unless otherwise specified. The DL monitoring BW is a bandwidth for monitoring a downlink control signal.

The method further comprises determining <NUM> a set of possible downlink control information, DCI, formats. Here, possible DCI formats are DCI formats compatible with the determined bandwidth. The set of DCI formats can for example be acquired from a table based on the determined bandwidth, i.e. the table comprises feasible mappings between DCI formats and bandwidths. For example, a first set of DCI formats for a first bandwidth may comprise DCI formats holding a first amount of information, and a second set of DCI formats for a second bandwidth may comprise DCI formats holding a second amount of information. The second bandwidth is here considered to be wider than the first bandwidth, and the second amount of information comprises information which is not a part of the first amount of information. Thus, the wider bandwidth may demand DCI formats holding more information. More information in this sense may for example be any of, or any combination of, a number of multiple-input-multiple-output, MIMO, layers above a first threshold, a modulation and coding scheme above a second threshold, a code rate above a third threshold, a resource block allocation pointing to resource blocks outside the first bandwidth, etc..

The method further comprises receiving <NUM> a transmission from a network node. Here, the reception may comprise control information which the wireless device desires to acquire. Thus, the method includes searching for control information in the transmission by decoding <NUM> using at least one of the DCI formats of the set. For example, the decoding may include attempting to decode control information using one of the DCIs, wherein the one of the DCIs may be selected using one or another method, e.g. based on historical information, likelihood calculations, randomly, in a fixed order, etc. An approach is to determine information about a number of possible Control Channel Elements, CCEs, which are usable for respective DCI format of the set, wherein the information about the number of possible CCEs is used for the decoding. It is then checked <NUM> if the decoding was successful. If decoding fails, the procedure continues with selecting <NUM> another DCI from the set and return to attempting to decode the control information. If decoding is successful, the method proceeds as demonstrated below.

When successful decoding of the control information has been accomplished, the method may include mapping <NUM> bits of payload of the transmission to the successfully used DCI format, and the method proceeds with performing <NUM> at least one task associated with the control information. That is, the wireless device has now acquired the desired control information and can act thereon.

When successful decoding has been accomplished, the wireless device is able to gain information from the control information. As discussed above, one part of the information may be about coming bandwidth configuration. Therefore, the method may include checking <NUM> whether bandwidth to be monitored is indicated to be changed. If no change in bandwidth is in forecast, the wireless device may proceed with receiving <NUM> next transmission using the same parameters again. However, if a change in bandwidth is indicated, the procedure starts all over again with determining <NUM> operation bandwidth for the monitoring.

In some embodiments, a blind decoding search is performed where the wireless device blindly tries to decode the control channel, e.g. PDCCH, by assuming the set of possible DCI formats allowed for the DL monitoring BW, possible in combination with possible code rates to be used for respective DCI format. In some embodiments, this is related to the number of possible CCEs that can be combined, i.e. aggregation levels, allowed which in LTE may be <NUM>, <NUM>, <NUM> or <NUM>. If a successful decoding is not determined the UE changes the DCI format hypothesis/aggregation level/start position of the decoding and make a new try until all hypotheses are tried. In some embodiments, the UE searches until it finds a valid DCI or all possibilities have been exhausted, i.e. at most one valid DCI can be found. In another embodiment, the wireless device trying all hypotheses and may find more than one valid DCI, e.g. one DL assignment and one UL grant. If successful coding is accomplished, the wireless device then maps the bits in payload to the determined DCI format / DCI formats, e.g. look up-table which may be based on specifications for the radio access technology used, and can interpret the bits and hence perform the task associated to the determined. The wireless device then continues to monitor the DL CCHs for information, and once information, which may be implicit or explicit as discussed above, indicates a need for change of the DL monitoring BW, the UE replaces the set of allowed DCI formats to the DCI formats allowed by the new configured DL monitoring BW. Optionally, the UE may also change DL monitoring BW so that the wide BW is applied all the time. In another embodiment, other triggers for changing the monitoring BW is possible, e.g. a separate channel or maybe some periodic timer indicating when the UE should change the DL monitoring BW. One example is that the change indication from narrowband to wideband DL monitoring BW could be an explicit bit, while the falling back to the narrowband DL monitoring bandwidth could be done via timers.

The set of DCI formats for the wide BW case does not necessarily imply a large DCI size. One could in some embodiment envision the same DCI size both for narrow and wide BW but in case of wide BW the RB allocation is based on larger groups of RBs than in the former case, i.e. for narrow BW each bit in a resource bitmap corresponds to a certain amount of RBs, in the wideband case each bit corresponds to a larger amount of RBs, and similarly for other ways of signalling RB allocations. That is, trading resolution for BW may be performed when entering a wideband mode.

In the discussion above, for the sake of easier understanding, the explanation has been based on that there is a narrower BW and a wider BW. However, the principle is applicable to three or more different BWs using the same approach as demonstrated above. Thus, the wireless device will then determine which of the BWs to use for monitoring a control channel. The determination may for example be based on a bit pattern.

<FIG> is a flow chart schematically illustrating a method of a network node of a radio access network. The method comprises configuring <NUM> a downlink bandwidth to be used at downlink transmissions, and determining <NUM> a DCI format based on the downlink bandwidth. Here, the appropriate DCI format is as discussed above. Thus, a first set of DCI formats for a first bandwidth may comprise DCI formats holding a first amount of information, and a second set of DCI formats for a second bandwidth may comprise DCI formats holding a second amount of information. The second bandwidth is here wider than the first bandwidth, and the second amount of information then comprises information which is not a part of the first amount of information. The information which is part of the second amount of information but not part of the first amount of information can for example comprises any of a number of multiple-input-multiple-output, MIMO, layers above a first threshold, a modulation and coding scheme above a second threshold, a code rate above a third threshold, a resource block allocation pointing to resource blocks outside the first bandwidth, etc..

A check <NUM> on whether there is data to transmit may be performed before transmitting <NUM> control information using a DCI with the determined DCI format. The check <NUM> may as well be performed before the configuration <NUM> of the bandwidth, wherein the amount, type, etc. of data may be taken into account when determining the appropriate bandwidth.

As control information has been transmitted <NUM>, a proper connection is assumed to be up and running, wherein the method may proceed with transmitting <NUM> data.

The network (NW) node, e.g. gNodeB, is serving a UE, the UE having capability to be configured with at least a first narrowband DL monitoring BW and a wideband DL monitoring BW, as has been described in detail above. The NW node starts to configure the DL monitoring BW according to the current need, which may be signalled from the UE or based on for example the amount of data waiting in the buffers for said UE, the past traffic history of said UE, the type of data, e.g. latency-critical or not, to be transmitted to said UE, etc. Based on the configured DL monitoring BW the NW node determines the set of DCI formats that can be used. For instance, in case a wideband DL monitoring BW is configured, the NW node needs to be able to point to a larger number of possible RBs the data can be scheduled on, for example a larger bit map implies a larger DCI payload, similarly also for other schemes such as signalling starting point and length of the allocation, compared to when a narrowband DL monitoring BW is used. Furthermore, since narrowband DL monitoring BW is mainly for power saving purposes, fewer MIMO-layers/antenna ports may be allowed, meaning fewer number of bits needed in the DCI to point out the currently used MIMO configuration compared to if the high throughput wideband DL monitoring BW is used, etc..

In other embodiments, also number of possible modulation schemes, code rate, etc. (MCS) to use may be different and hence also number of bits for representing the chosen MCS. In other embodiments, one could have different possibilities in terms of cross-slot scheduling, both for DL and UL, depending on narrowband/wideband PDCCH. In yet another embodiment different number of bits to indicate the monitoring BW in the future, for instance narrow BW needs a bit to switch to wide BW, but maybe no bit for switching back is needed in a timer embodiment as described above. The scheduler then monitors if there is any data to be scheduled to the UE, and if so, the NW node determines data allocation in the PDSCH, MIMO scheme to use etc. and configures the needed DCI and transmit control information according to the determined need.

The methods according to the present invention are suitable for implementation with aid of processing means, such as computers and/or processors, especially for the case where the processing elements <NUM> and <NUM> demonstrated above comprises a processor <NUM>, <NUM> handling and/or controlling actions of the respective methods. Therefore, there are provided computer programs, comprising instructions arranged to cause the processing means, processor, or computer to perform the steps of any of the methods according to any of the embodiments described with reference to <FIG> and <FIG>, respectively. The computer programs preferably comprise program code which is stored on a computer readable medium <NUM>, as illustrated in <FIG>, which can be loaded and executed by a processing means, processor, or computer <NUM> to cause it to perform the methods, respectively, according to embodiments of the present invention, preferably as any of the embodiments described with reference to <FIG> and <FIG>. The computer <NUM> and computer program product <NUM> can be arranged to execute the program code sequentially where actions of the any of the methods are performed stepwise, or be arranged to perform the actions on a real-time basis. The processing means, processor, or computer <NUM> is preferably what normally is referred to as an embedded system. Thus, the depicted computer readable medium <NUM> and computer <NUM> in <FIG> should be construed to be for illustrative purposes only to provide understanding of the principle, and not to be construed as any direct illustration of the elements.

<FIG> illustrates a wireless network comprising a more detailed view of a network node <NUM> and a communication device <NUM>. For simplicity, <FIG> only depicts network <NUM>, network nodes <NUM> and 200a, and communication device <NUM>. Network node <NUM> comprises processor <NUM>, storage <NUM>, interface <NUM>, and antenna 201a. Similarly, the communication device <NUM> comprises processor <NUM>, storage <NUM>, interface <NUM> and antenna 211a. These components may work together in order to provide network node and/or wireless device functionality. The wireless network may comprise any number of wired or wireless networks, network nodes, base stations, controllers, wireless devices, relay stations, and/or any other components that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections.

Network <NUM> may comprise one or more IP networks, public switched telephone networks (PSTNs), packet data networks, optical networks, wide area networks (WANs), local area networks (LANs), wireless local area networks (WLANs), wired networks, wireless networks, metropolitan area networks, and other networks to enable communication between devices.

Network node <NUM> comprises processor <NUM>, storage <NUM>, interface <NUM>, and antenna 201a. These components are depicted as single boxes located within a single larger box. In practice however, a network node may comprise multiple different physical components that make up a single illustrated component (e.g., interface <NUM> may comprise terminals for coupling wires for a wired connection and a radio transceiver for a wireless connection). Similarly, network node <NUM> may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, a BTS component and a BSC component, etc.), which may each have their own respective processor, storage, and interface components. In such a scenario, each unique NodeB and BSC pair, may be a separate network node. The network node <NUM> may be configured to support multiple radio access technologies (RATs). Thus, some components may be duplicated (e.g., separate storage <NUM> for the different RATs) and some components may be reused (e.g., the same antenna 201amay be shared by the RATs).

Processor <NUM> may be a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node <NUM> components, such as storage <NUM>, network node <NUM> functionality. For example, processor <NUM> may execute instructions stored in storage <NUM>. Such functionality may include providing various wireless features discussed herein to a wireless device, such as WD <NUM>, including any of the features or benefits disclosed herein.

Storage <NUM> may comprise any form of volatile or non-volatile computer readable memory including, without limitation, persistent storage, solid state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), removable media, or any other suitable local or remote memory component. Storage <NUM> may store any suitable instructions, data or information, including software and encoded logic, utilized by network node <NUM>. Storage <NUM> may be used to store any calculations made by processor <NUM> and/or any data received via interface <NUM>.

Network node <NUM> also comprises interface <NUM> which may be used in the wired or wireless communication of signalling and/or data between network node <NUM>, network <NUM>, and/or WD <NUM>. For example, interface <NUM> may perform any formatting, coding, or translating that may be needed to allow network node <NUM> to send and receive data from network <NUM> over a wired connection. Interface <NUM> may also include a radio transmitter and/or receiver that may be coupled to or a part of antenna 201a. The radio may receive digital data that is to be sent out to other network nodes or WDs via a wireless connection. The radio may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters. The radio signal may then be transmitted via antenna 201a to the appropriate recipient (e.g., WD <NUM>).

Antenna 201a may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. The antenna 201a may comprise one or more omni-directional, sector or panel antennas operable to transmit/receive radio signals between, for example, <NUM> and <NUM>. An omni-directional antenna may be used to transmit/receive radio signals in any direction, a sector antenna may be used to transmit/receive radio signals from devices within a particular area, a panel antenna may be a line of sight antenna used to transmit/receive radio signals in a relatively straight line, and an array of antenna elements may be used for providing a beamforming transmission and/or reception pattern.

WD <NUM> may be any type of communication device, wireless device, UE, D2D device or ProSe UE, but may in general be any device, sensor, actuator, smart phone, modem, laptop, Personal Digital Assistant (PDA), tablet, mobile terminal, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), Universal Serial Bus (USB) dongles, machine type UE, UE capable of machine to machine (M2M) communication, etc., which is able to wirelessly send and receive data and/or signals to and from a network node, such as network node <NUM> and/or other WDs. WD <NUM> comprises processor <NUM>, storage <NUM>, interface <NUM>, and antenna 211a. Like network node <NUM>, the components of WD <NUM> are depicted as single boxes located within a single larger box, however in practice a wireless device may comprises multiple different physical components that make up a single illustrated component (e.g., storage <NUM> may comprise multiple discrete microchips, each microchip representing a portion of the total storage capacity).

Processor <NUM> may be a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in combination with other WD <NUM> components, such as storage <NUM>, WD <NUM> functionality. Such functionality may include providing various wireless features discussed herein, including any of the features or benefits disclosed herein.

Storage <NUM> may be any form of volatile or non-volatile memory including, without limitation, persistent storage, solid state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), removable media, or any other suitable local or remote memory component. Storage <NUM> may store any suitable data, instructions, or information, including software and encoded logic, utilized by WD <NUM>. Storage <NUM> may be used to store any calculations made by processor <NUM> and/or any data received via interface <NUM>.

Interface <NUM> may be used in the wireless communication of signalling and/or data between WD <NUM> and network node <NUM>. For example, interface <NUM> may perform any formatting, coding, or translating that may be needed to allow WD <NUM> to send and receive data from network node <NUM> over a wireless connection. Interface <NUM> may also include a radio transmitter and/or receiver that may be coupled to or a part of antenna 211a. The radio may receive digital data that is to be sent out to network node <NUM> via a wireless connection. The radio may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters. The radio signal may then be transmitted via antenna 211a to network node <NUM>.

Antenna 211a may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. The antenna 211a may comprise one or more omni-directional, sector or panel antennas operable to transmit/receive radio signals between <NUM> and <NUM>. For simplicity, antenna 211a may be considered a part of interface <NUM> to the extent that a wireless signal is being used.

The components described above may be used to implement one or more functional modules used in D2D communication. The functional modules may comprise software, computer programs, sub-routines, libraries, source code, or any other form of executable instructions that are run by, for example, a processor. In general terms, each functional module may be implemented in hardware and/or in software. Preferably, one or more or all functional modules may be implemented by processors <NUM> and/or <NUM>, possibly in cooperation with storage <NUM> and/or <NUM>. Processors <NUM> and/or <NUM> and storage <NUM> and/or <NUM> may thus be arranged to allow processors <NUM> and/or <NUM> to fetch instructions from storage <NUM> and/or <NUM> and execute the fetched instructions to allow the respective functional module to perform any features or functions disclosed herein. The modules may further be configured to perform other functions or steps not explicitly described herein but which would be within the knowledge of a person skilled in the art.

Claim 1:
A method performed by a wireless device comprising
determining (<NUM>) a first bandwidth for monitoring a downlink control signal;
determining (<NUM>) a first set of possible downlink control indicator, DCI, formats that are compatible with the first bandwidth;
receiving (<NUM>) a first transmission from a network node using the first bandwidth;
blindly decoding (<NUM>) control information in the first transmission by using at least one DCI format of the first set of DCI formats; and
when successful decoding of the control information, checking (<NUM>) whether bandwidth to be monitored is indicated by the control information in the first transmission to be changed to a second bandwidth, and when bandwidth is indicated to be changed:
determining the second bandwidth for downlink control signal monitoring, determining a second set of possible downlink control indicator, DCI, formats that are compatible with the second bandwidth, receiving a second transmission from the network node using the second bandwidth, and blindly decoding control information in the second transmission by using at least one DCI format of the second set of DCI formats.