WO2013127088A1

WO2013127088A1 - Method and apparatus for downlink control channel detection

Info

Publication number: WO2013127088A1
Application number: PCT/CN2012/071863
Authority: WO
Inventors: Chunyan Gao; Na WEI; Jing HAN; Wei Bai; Haiming Wang; Shuang TAN
Original assignee: Renesas Mobile Corporation
Priority date: 2012-03-02
Filing date: 2012-03-02
Publication date: 2013-09-06

Abstract

A method is provided for downlink control channel detection. The method may include determining, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant. The method may further include performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant. A corresponding apparatus and computer program product are also provided.

Description

METHOD AND APPARATUS FOR DOWNLINK CONTROL CHANNEL DETECTION

TECHNOLOGICAL FIELD

[0001] Embodiments of the present invention relate generally to wireless communication technology and, more particularly, relate to an apparatus, method and computer program product for downlink control channel detection.

BACKGROUND

[0002] The modern communications era has brought about a tremendous expansion of wireless network technology, driven by consumer demands. This expansion of wireless and mobile networking technologies have addressed related consumer demands, while providing more flexibility and immediacy of information transfer and providing convenience to users.

[0003] Current and future networking technologies continue to facilitate ease of information transfer and convenience to users. In order to provide easier or faster information transfer and convenience, telecommunication industry service providers are _. developing improvements to existing networks. One ongoing area of development in networking and communication technology is the development of machine-type

communications (MTC) technology. MTC devices are generally targeted at low-end (low cost, low data rate) applications that can be handled adequately by legacy cellular networking technologies, such as GSM/GPRS (Global System for Mobile Communications/General

Packet Radio Service). As more and more MTC devices configured for use of legacy cellular networking technologies are deployed in the field, this naturally increases the reliance on legacy networks. Continuing reliance on legacy networks may negatively impact network operators, as well as users of cellular networks, however. In this regard, as more modern cellular networking technologies, such as Long Term Evolution (LTE) technologies, are deployed and achieve widespread use by higher end consumer devices, network operators will be impacted by the costs of having to maintain multiple radio access technologies (RATs), as well as the cost of not being able to reap the maximum benefit out of a finite allocated spectrum given the non-optimal spectrum efficiency of legacy access technologies, such as GSM/GPRS.

BRIEF SUMMARY OF EXAMPLE EMBODIMENTS

[0004] Methods, apparatuses and computer program products are provided herein for downlink control channel detection. Embodiments provided herein may provide several advantages to network operators, wireless service providers, computing devices, and computing device users. In this regard, some example embodiments reduce a burden of downlink control channel detection on terminal apparatuses, by limiting a number of subframes in which downlink control channel detection for dedicated signaling is performed so as to avoid unnecessary downlink control channel detection. Accordingly, power consumption by terminal apparatuses may be reduced. As such, power-limited devices, such as MTC devices, may benefit by way of the reduced power consumption that may come with a reduced downlink control channel detection burden. The reduced downlink control channel detection burden may also benefit network operators, as it will increase the ability to implement MTC devices on modern cellular networks, such as LTE networks. Accordingly, network operators may be enabled to switch support and spectrum usage from legacy networks to newer networks, providing reduced RAT maintenance cost and more efficient spectrum usage,

[0005] In a first example embodiment, a method is provided, which may comprise determining, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant. The method of this example embodiment may further comprise performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant. The method of the first example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0006] In a second example embodiment, an apparatus comprising at least one processor and at least one memory including computer program code is provided. The at least one memory and the computer program code are configured, with the at least one processor to cause the apparatus of this example embodiment to at least determine, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant. The at least one memory and the computer program code may be configured, with the at least one processor to further cause the apparatus of this example embodiment to perform downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant. The apparatus of the second example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0007] In a third example embodiment, a computer program product comprising at least one non-transitory computer-readable storage medium having computer-readable program code stored therein is provided. The computer-readable program code of this example embodiment may include instructions configured to cause an apparatus to at least determine, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant. The computer-readable program code of this example embodiment may further include instructions configured to cause an apparatus to perform downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant. The computer program product of the third example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0008] In a fourth example embodiment, an apparatus is provided, which may comprise means for determining, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant. The apparatus of this example embodiment may further comprise means for performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant. The apparatus of the fourth example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0009] In a fifth example embodiment, a method is provided, which may comprise defining a configuration signaling for sending to a terminal apparatus. The configuration signaling of this example embodiment may include information enabling the terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant. The method of this example embodiment may further comprise scheduling an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes. The method of the fifth example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0010] In a sixth example embodiment, an apparatus comprising at least one processor and at least one memory including computer program code is provided. The at least one memory and the computer program code are configured, with the at least one processor to cause the apparatus of this example embodiment to at least define a configuration signaling for sending to a terminal apparatus. The configuration signaling of this example embodiment may include information enabling the terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant. The at least one memory and the computer program code may be configured, with the at least one processor to further cause the apparatus of this example embodiment to schedule an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes. The apparatus of the sixth example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0011] in a seventh example embodiment, a computer program product comprising at least one non-transitory computer-readable storage medium having computer-readable program code stored therein is provided. The computer-readable program code may include instructions configured to cause an apparatus to at least define a configuration signaling for sending to a terminal apparatus. The configuration signaling of this example embodiment may include information enabling the terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant. The computer-readable program code may further include instructions configured to cause an apparatus to schedule an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes. The computer program product of the seventh example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0012] In an eighth example embodiment, an apparatus is provided, which may comprise means for defining a configuration signaling for sending to a terminal apparatus. The configuration signaling of this example embodiment may include information enabling the terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant. The apparatus of this example embodiment may further comprise scheduling an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes, The apparatus of the eighth example embodiment provides power savings to a terminal apparatus by avoiding unnecessary downlink control channel detection.

[0013] The above summary is provided merely for purposes of summarizing some example embodiments of the invention so as to provide a basic understanding of some aspects of the invention. Accordingly, it will be appreciated that the above described example embodiments are merely examples and should not be construed to narrow the scope or spirit of the invention in any way. It will be appreciated that the scope of the invention encompasses many potential embodiments, some of which will be further described below, in addition to those here summarized. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0014] Having thus described embodiments of the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

[0015] FIG. 1 illustrates an example system for facilitating downlink control channel detection according to some example embodiments;

[0016] FIG. 2 illustrates a block diagram of a terminal apparatus in accordance with some example embodiments;

[0017] FIG. 3 illustrates a block diagram of a network access point apparatus in accordance with some example embodiments;

[0018] FIG. 4 illustrates an example an example uplink grant format according to some example embodiments;

[0019] FIG. 5 illustrates a flowchart according to an example method for performing downlink control channel detection according to some example embodiments; and

[0020] FIG. 6 illustrates a flowchart according to an example method for facilitating downlink control channel detection according to some example embodiments.

DETAILED DESCRIPTION

[0021] Some embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, various embodiments of the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout.

[0022] As used herein, the terms "data," "content," "information" and similar terms may be used interchangeably to refer to data capable of being transmitted, received, displayed and/or stored in accordance with various example embodiments. Thus, use of any such terms should not be taken to limit the spirit and scope of the disclosure. Further, where a computing device is described herein to receive data from another computing device, it will be appreciated that the data may be received directly from the another computing device or may be received indirectly via one or more intermediary computing devices, such as, for example, one or more servers, relays, routers, network access points, base stations, and/or the like. Additionally, where a computing device is described herein to send data "to" or "toward" another computing device, it will be appreciated that the data may be sent directly to the destination computing device, or may be relayed via one or more intermediary computing devices, such as, for example, one or more servers, relays, routers, network access points, base stations, and/or the like toward the destination computing device.

[0023] As used in this application, the term 'circuitry' refers to all of the following: (a)hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and (b) to combinations of circuits and software (and/or firmware), such as (as applicable): (i) to a combination of processor(s) or (ii) to portions of processor(s)/software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.

i0024J This definition of 'circuitry' applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term "circuitry" would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware. The term "circuitry" would also cover, for example and if applicable to the particular claim element, a baseband integrated circuit or applications processor integrated circuit for a mobile phone or a similar integrated circuit in server, a cellular network device, or other network device.

[0025] MTC devices are often used for functions, such as metering, monitoring, and road security. These applications are generally uplink dominant in nature. In this regard, unlike traditional human-to-human services, there is generally more uplink traffic than downlink in most MTC applications, and the majority of downlink data is control or configuration information. In a time-division duplex (TDD) cell, the TDD configuration may be determined based on the average downlink/uplink (DL UL) traffic of all terminals and all applications on the cell. As such, while some applications on the cell may be UL dominant, the TDD configuration of the cell may be a DL heavy configuration, such as TDD

configuration 1. In such a case, it may be a waste of power for a user equipment (UE) to detect a physical downlink control channel (PDCCH) in all of the DL subframes. In this regard, for a UE that is UL heavy, there may rarely be a DL grant for the UE in the DL subframes.

[0026] For a UE having a discontinuous reception (DRX) configuration, PDCCH detection only needs to be performed during the active time in each DRX duration. However, the DRX configuration cannot account for the UL heavy traffic characteristics of some UEs, such as MTCs. In this regard, in accordance with a DRX configuration, the UL grant detection may be disabled in the inactive time of DRX duration, while PDCCH detection for both DL grant and UL grant may be enabled in the active time of DRX duration even in instances in which there is only UL traffic. As such, a UE may waste power by performing unnecessary PDCCH detection.

[0027] Some example embodiments provide for reduced power consumption by terminal apparatuses, such as MTC UEs, by providing improved rules for downlink control channel (e.g., PDCCH and/or the like) detection for dedicated signaling that may reduce the amount of unnecessary downlink control channel detection that may be performed by a terminal apparatus. Accordingly, some example embodiments described herein below reduce power consumption by terminal apparatuses, thus benefiting terminal apparatuses, such as MTC UEs, that may rely on a battery or other finite power source.

[0028] FIG. 1 illustrates an example system 100 for facilitating downlink control channel detection in accordance with some example embodiments. It will be appreciated that the system 100 as well as the illustrations in other figures are each provided as an example of an embodiment(s) and should not be construed to narrow the scope or spirit of the disclosure in any way. In this regard, the scope of the disclosure encompasses many potential

embodiments in addition to those illustrated and described herein. As such, while FIG. 1 illustrates one example of a configuration of a system for facilitating downlink control channel detection, embodiments of the present invention may be implemented in systems having numerous other configurations.

[0029] The system 100 may include an access point 104 that may provide wireless access to a network 106, The access point 106 may comprise any entity configured to provide radio access to the network 106. By way of non-limiting example, the access point 106 may comprise a base station, base transceiver station, node B, evolved node B (eNB), and/or the like.

[0030] The network 106 may comprise one or more wireless networks (for example, a cellular network, wireless local area network, wireless personal area network, wireless metropolitan area network, and/or the like), one or more wireline networks, or some combination thereof, and in some embodiments may comprise at least a portion of the internet. In some example embodiments, the network 106 may employ one or more mobile access mechanisms, such as Long Term Evolution (e.g., LTE, LTE-A, and/or the like), Time Division Synchronous Code Division Multiple Access (TDSCMA), wideband code division multiple access (W-CDMA), CDMA2000, global system for mobile communications (GSM), general packet radio service (GPRS), and/or the like. As such, it will be appreciated that where embodiments are described herein with respect to LTE systems, such as current and future iterations of LTE and/or LTE-A systems, the use of LTE is by way of example and not by way of limitation. In this regard, example embodiments disclosed herein may be employed in accordance with any wireless networking technology, protocol, or standard in which downlink control channel detection, such as PDCCH detection, may be performed.

[0031] As such, it will be appreciated, that where references herein are made to a particular network standard and/or terminology particular to a network standard, the references are provided merely by way of example and not by way of limitation. Thus, for example, where example embodiments are described to use an "eNB," UE, and/or LTE radio access technology, it will be appreciated that, other types of access points, terminal apparatuses, and/or radio access technologies may be substituted within the scope of the disclosure. Similarly, where examples are described in terms of PDCCH detection, it will be appreciated that embodiments may be applied to other types of downlink control channel detection that may be performed in accordance with one or more example embodiments.

[0032] The system 100 may further comprise one or more terminal apparatuses 102, which may be provided with wireless access to the network 106 by the access point 104. By way of non-limiting example, a terminal apparatus 102 may be embodied as a mobile communication device, mobile telephone, personal digital assistant (PDA), smart phone, tablet computing device, pager, laptop computer, desktop computer with a cellular network adapter, portable game device, audio/video player, television device, radio receiver, a digital camera/camcorder, positioning device, MTC device, some combination thereof, or the like. In some example embodiments, a terminal apparatus 102 may be embodied as a UE, such as an MTC UE, which may be configured to access a cellular network, such as an LTE network. It will be appreciated, however, that illustrations and discussion referencing a UE(s) are provided by way of example, and not by way of limitation, as where examples are described and/or illustrated to use UEs, any type of terminal apparatus may be substituted for a UE within the scope of the disclosure.

[0033] FIG. 2 illustrates a block diagram of a terminal apparatus 202 in accordance with some example embodiments. The terminal apparatus 202 may comprise an apparatus that may be implemented on a terminal apparatus 102 in accordance with some example embodiments. It should be noted, however, that the components, devices or elements illustrated in and described with respect to FIG. 2 below may not be mandatory and thus some may be omitted in certain embodiments. Additionally, some embodiments may include further or different components, devices or elements beyond those illustrated in and described with respect to FIG. 2.

[0034] In some example embodiments, the terminal apparatus 202 may include or otherwise be in communication with processing circuitry 210 that is configurable to perform actions in accordance with one or more example embodiments disclosed herein. In this regard, the processing circuitry 210 may be configured to perform and/or control

performance of one or more functionalities of the terminal apparatus 202 in accordance with various example embodiments, and thus may provide means for performing functionalities of the terminal apparatus 202 in accordance with various example embodiments. The processing circuitry 210 may be configured to perform data processing, application execution and/or other processing and management services according to one or more example embodiments. In some embodiments, the terminal apparatus 202 or a portion(s) or component(s) thereof, such as the processing circuitry 210, may be embodied as or comprise a chip or chip set. In other words, the terminal apparatus 202 or the processing circuitry 210 may comprise one or more physical packages (e.g., chips) including materials, components and/or wires on a structural assembly (e.g., a baseboard). The structural assembly may provide physical strength, conservation of size, and/or limitation of electrical interaction for component circuitry included thereon. The terminal apparatus 202 or the processing circuitry 210 may therefore, in some cases, be configured to implement an embodiment of the invention on a single chip or as a single "system on a chip." As such, in some cases, a chip or chipset may constitute means for performing one or more operations for providing the functionalities described herein.

[0035] In some example embodiments, the processing circuitry 210 may include a processor 212 and, in some embodiments, such as that illustrated in FIG. 2, may further include memory 214. The processing circuitry 210 may be in communication with or otherwise control a user interface 216, a communication interface 218, and/or a detection controller 220. As such, the processing circuitry 210 may be embodied as a circuit chip (e.g., an integrated circuit chip) configured (e.g., with hardware, software or a combination of hardware and software) to perform operations described herein.

[0036] In some example embodiments, one or more of the elements illustrated in FIG. 2 may provide a processing system, which may be arranged to perform one or more

functionalities attributed to the terminal apparatus 202 in accordance with various example embodiments. In this regard, in some example embodiments, the processing circuitry 210, processor 212, memory 214, user interface 216, communication interface 218, detection controller 220, or some combination thereof may form a processing system.

[0037] The processor 2 2 may be embodied in a number of different ways. For example, the processor 212 may be embodied as various processing means such as one or more of a microprocessor or other processing element, a coprocessor, a controller or various other computing or processing devices including integrated circuits such as, for example, an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), or the like. Although illustrated as a single processor, it will be appreciated that the processor 212 may comprise a plurality of processors. The plurality of processors may be in operative

communication with each other and may be collectively configured to perform one or more functionalities of the terminal apparatus 202 as described herein. The plurality of processors may be embodied on a single computing device or distributed across a plurality of computing devices collectively configured to function as the terminal apparatus 202. In some example embodiments, the processor 212 may be configured to execute instructions stored in the memory 214 or otherwise accessible to the processor 212. As such, whether configured by hardware or by a combination of hardware and software, the processor 212 may represent an entity (e.g., physically embodied in circuitry - in the form of processing circuitry 210) capable of performing operations according to embodiments of the present invention while configured accordingly. Thus, for example, when the processor 212 is embodied as an ASIC, FPGA or the like, the processor 212 may be specifically configured hardware for conducting the operations described herein. Alternatively, as another example, when the processor 212 is embodied as an executor of software instructions, the instructions may specifically configure the processor 212 to perform one or more operations described herein.

[0038] In some example embodiments, the memory 214 may include one or more non- transitory memory devices such as, for example, volatile and/or non-volatile memory that may be either fixed or removable. In this regard, the memory 214 may comprise a non- transitory computer-readable storage medium. It will be appreciated that while the memory 214 is illustrated as a single memory, the memory 214 may comprise a plurality of memories. The plurality of memories may be embodied on a single computing device or may be distributed across a plurality of computing devices collectively configured to function as the terminal apparatus 202. The memory 214 may be configured to store information, data, applications, instructions or the like for enabling the terminal apparatus 202 to carry out various functions in accordance with one or more example embodiments. For example, the memory 214 may be configured to buffer input data for processing by the processor 212, Additionally or alternatively, the memory 214 may be configured to store instructions for execution by the processor 212. As yet another alternative, the memory 214 may include one or more databases that may store a variety of files, contents or data sets. Among the contents of the memory 214, applications may be stored for execution by the processor 212 in order to carry out the functionality associated with each respective application. In some cases, the memory 214 may be in communication with one or more of the processor 212, user interface 216, communication interface 218, or detection controller 220 via a bus(es) for passing information among components of the terminal apparatus 202.

[0039] The user interface 216 (if implemented) may be in communication with the processing circuitry 210 to receive an indication of a user input at the user interface 216 and/or to provide an audible, visual, mechanical or other output to the user. As such, the user interface 216 may include, for example, a keyboard, a mouse, a joystick, a display, a touch screen, a microphone, a speaker, and/or other input/output mechanisms.

[0040] The communication interface 218 may include one or more interface mechanisms for enabling communication with other devices and/or networks. In some cases, the communication interface 218 may be any means such as a device or circuitry embodied in either hardware, or a combination of hardware and software that is configured to receive and/or transmit data from/to a network and/or any other device or module that may be in communication with the processing circuitry 210. By way of example, the communication interface 218 may be configured to provide a cellular network interface (e.g., a cellular modem) to enable the terminal apparatus 202 to interface with a cellular network, such as via an access point 104. Accordingly, in some example embodiments, the communication interface 218 may be configured to enable the terminal apparatus 202 to associate with and access the network 106 via the access point 104. The communication interface 218 may include, for example, an antenna (or multiple antennas) and supporting hardware and/or software for enabling communications with a wireless communication network (e.g., a cellular network, WSN, and/or the like) and/or a communication modem or other

hardware/software for supporting communication via cable, digital subscriber line (DSL), universal serial bus (USB), Ethernet or other methods.

[001] In some example embodiments, the processor 212 (or the processing circuitry 210) may be embodied as, include, or otherwise control a detection controller 220. As such, the detection controller 220 may be embodied as various means, such as circuitry, hardware, a computer program product comprising computer readable program instructions stored on a computer readable medium (for example, the memory 214) and executed by a processing device (for example, the processor 212), or some combination thereof. The detection controller 220 ma be capable of communication with one or more of the memory 214, user interface 216, or communication interface 218 to access, receive, and/or send data as may be needed to perform one or more of the functionalities of the detection controller 220 as described herein. In some example embodiments, the detection controller 220 may be configured to control operation of the communication interface 218. Thus, for example, where the detection controller 220 is described to cause information to be sent to another computing device, such as to the access point apparatus 104, an entity that may be accessible via the network 106, and/or other entity, it will be appreciated that the detection controller 220 may cause the information to be sent by controlling the communication interface 218 to send the information.

[0041] FIG. 3 illustrates a block diagram of an access point apparatus 302 in accordance with some example embodiments. In this regard, the access point apparatus 302 illustrates an example of an apparatus that may be implemented on an access point 104 in accordance with some example embodiments. However, it should be noted that the components, devices or elements illustrated in and described with respect to FIG. 3 below may not be mandatory and thus some may be omitted in certain embodiments. Additionally, some embodiments may include further or different components, devices or elements beyond those illustrated in and described with respect to FIG. 3.

[0042] In some example embodiments, the access point apparatus 302 may include or otherwise be in communication with processing circuitry 310 that is configurable to perform actions in accordance with one or more example embodiments disclosed herein. In this regard, the processing circuitry 310 may be configured to perform and/or control

performance of one or more functionalities of the access point apparatus 302 in accordance with various example embodiments, and thus may provide means for performing

functionalities of the access point apparatus 302 in accordance with various example embodiments. The processing circuitry 310 may be configured to perform data processing, application execution and/or other processing and management services according to one or more example embodiments. In some embodiments, the access point apparatus 302 or a portion(s) or component(s) thereof, such as the processing circuitry 310, may be embodied as or comprise a chip or chip set. In other words, the access point apparatus 302 or the processing circuitry 310 may comprise one or more physical packages (e.g., chips) including materials, components and/or wires on a structural assembly (e.g., a baseboard). The structural assembly may provide physical strength, conservation of size, and/or limitation of electrical interaction for component circuitry included thereon. The access point apparatus 302 or the processing circuitry 310 may therefore, in some cases, be configured to implement an embodiment of the invention on a single chip or as a single "system on a chip," As such, in some cases, a chip or chipset may constitute means for performing one or more operations for providing the functionalities described herein.

[0043] In some example embodiments, the processing circuitry 310 may include a processor 312 and, in some embodiments, such as that illustrated in FIG. 3, may further include memory 314. The processing circuitry 310 may be in communication with or otherwise control a communication interface 316, and/or a scheduling controller 318. The processing circuitry 310 may be embodied as a circuit chip (e.g., an integrated circuit chip) configured (e.g., with hardware, software or a combination of hardware and software) to perform operations described herein. However, in some embodiments, the processing circuitry 310 may be embodied as a portion of a server, computer, workstation or other computing device.

[0044] In some example embodiments, one or more of the elements illustrated in FIG. 3 may provide a processing system, which may be arranged to perform one or more

functionalities attributed to the access point apparatus 302 in accordance with various example embodiments. In this regard, in some example embodiments, the processing circuitry 310, processor 312, memory 314, communication interface 316, scheduling controller 318, or some combination thereof may form a processing system.

[0045] The processor 312 may be embodied in a number of different ways. For example, the processor 312 may be embodied as various processing means such as one or more of a microprocessor or other processing element, a coprocessor, a controller or various other computing or processing devices including integrated circuits such as, for example, an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), or the like. Although illustrated as a single processor, it will be appreciated that the processor 312 may comprise a plurality of processors. The plurality of processors may be in operative

communication with each other and may be collectively configured to perform one or more functionalities of the access point apparatus 302 as described herein. The plurality of processors may be embodied on a single computing device or distributed across a plurality of computing devices collectively configured to function as the access point apparatus 302. In some example embodiments, the processor 312 may be configured to execute instructions stored in the memory 314 or otherwise accessible to the processor 312. As such, whether configured by hardware or by a combination of hardware and software, the processor 312 may represent an entity (e.g., physically embodied in circuitry - in the form of processing circuitry 310) capable of performing operations according to embodiments of the present invention while configured accordingly. Thus, for example, when the processor 312 is embodied as an ASIC, FPGA or the like, the processor 312 may be specifically configured hardware for conducting the operations described herein. Alternatively, as another example, when the processor 312 is embodied as an executor of software instructions, the instructions may specifically configure the processor 312 to perform one or more operations described herein.

[0046] In some example embodiments, the memory 314 may include one or more non- transitory memory devices such as, for example, volatile and/or non- vol tile memory that may be either fixed or removable. In this regard, the memory 314 may comprise a non- transitory computer-readable storage medium. It will be appreciated that while the memory 314 is illustrated as a single memory, the memory 314 may comprise a plurality of memories. The plurality of memories may be embodied on a single computing device or may be distributed across a plurality of computing devices collectively configured to function as the access point apparatus 302. The memory 314 may be configured to store information, data, applications, instructions or the like for enabling the access point apparatus 302 to carry out various functions in accordance with one or more example embodiments. For example, the memory 314 may be configured to buffer input data for processing by the processor 312. Additionally or alternatively, the memory 314 may be configured to store instructions for execution by the processor 312. As yet another alternative, the memory 314 may include one or more databases that may store a variety of files, contents or data sets. Among the contents of the memory 314, applications may be stored for execution by the processor 312 in order to carry out the functionality associated with each respective application. In some cases, the memory 314 may be in communication with one or more of the processor 312,

communication interface 316, or scheduling controller 318 via a bus(es) for passing information among components of the access point apparatus 302.

[0047] The communication interface 316 may include one or more interface mechanisms for enabling communication with other devices and/or networks. In some example

embodiments, the communication interface 316 may be any means such as a device or circuitry embodied in either hardware, or a combination of hardware and software that is configured to receive and/or transmit data from/to a network and/or any other device or module that may be in communication with the processing circuitry 310. By way of example, the communication interface 316 may be configured to facilitate the provision of radio access to the network 106 to one or more terminal apparatuses 102. The communication interface 316 may accordingly include, for example, an antenna (or multiple antennas) and supporting hardware and/or software for enabling communications with a wireless communication network and/or a communication modem or other hardware/software for supporting communication via cable, digital subscriber line (DSL), universal serial bus (USB), Ethernet or other methods.

[002] In some example embodiments, the processor 312 (or the processing circuitry 310) may additionally or alternatively be embodied as, include, or otherwise control a scheduling controller 318. As such, the scheduling controller 318 may be embodied as various means, such as circuitry, hardware, a computer program product comprising a computer readable medium (for example, the memory 314) storing computer readable program instructions executable by a processing device (for example, the processor 312), or some combination thereof. The scheduling controller 318 may be capable of communication with one or more of the memory 314, or communication interface 316 to access, receive, and/or send data as may be needed to perform one or more of the functionalities of the scheduling controller 318 as described herein. In some example embodiments, the scheduling controller 318 may be configured to control operation of the communication interface 316. Thus, for example, where the scheduling controller 318 is described to cause information to be sent to another computing device, such as to a terminal apparatus 102, it will be appreciated that the scheduling controller 318 may cause the information to be sent by controlling the

communication interface 316 to send the information.

[0048] In some example embodiments, a scheduling controller 318 that may be

associated with an access point 104 may be configured to define a control signaling for sending to a terminal apparatus 102. The configuration signaling may include information enabling the terminal apparatus 102 to determine a subset of downlink subframes within a frame that potentially include an uplink (UL) grant. In this regard, the configuration signaling may include information enabling the terminal apparatus 102 to implicitly derive a subset of downlink subframes to which inclusion of an uplink grant may be restricted in accordance with some example embodiments.

[0049] The information included in the configuration signaling may, for example, include hybrid automatic repeat request (HARQ) configuration information. For example, the information included in the configuration signaling may comprise a time-division duplex (TDD) configuration that may be associated with a cell that may be serving the terminal apparatus 102, an indication of an UL HARQ timing associated with a cell that may be serving the terminal apparatus 102, an UL HARQ configuration that may specify a number of HARQ processes within a frame, and/or the like.

[0050] The scheduling controller 318 may be further configured to cause the access point 104 to send the defined configuration signaling toward the intended terminal apparatus 102, such as over a radio interface between the access point 104 and terminal apparatus 102. The scheduling controller 318 may be further configured to schedule any uplink grant for the terminal apparatus 102 only within a downlink (DL) subframe in the subset of subframes that may be implicitly derived by the terminal apparatus 102 based at least in part on the information included in the configuration signaling sent to the terminal apparatus 102. An uplink grant for the terminal apparatus 102 may comprise a dedicated uplink grant for the specific terminal apparatus 102 to which it is sent. In some example embodiments, the scheduling controller 318 may be configured to schedule an uplink grant for transmission on a downlink control channel, such as a PDCCH, in a downlink subframe in the subset of subframes that may be implicitly derived by the terminal apparatus 102 based at least in part on the information included in the configuration signaling sent to the terminal apparatus 102.

[0051] The detection controller 220 that may be associated with a terminal apparatus 102 may receive configuration signaling sent to the terminal apparatus 102 by an access point 104. The detection controller 220 may be configured to determine, based at least in part on information included in the received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant. Accordingly, the detection controller 220 may be configured to determine an implicit restriction on the downlink subframes which may contain uplink grants based at least in part on configuration signaling sent by the access point 104.

[0052] The detection controller 220 may be configured to perform downlink control channel detection (e.g., PDCCH) detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant. Accordingly, the detection controller 220 may avoid performing downlink control channel detection in downlink subframes that, by implicit restriction in accordance with some example embodiments, may not include an uplink grant.

[0053] In some example embodiments, the detection controller 220 may be configured to determine the subset of downlink subframes that potentially include an uplink grant based at least in part on a HARQ timing that may be associated with a cell that may be serving the terminal apparatus 102. In an instance in which a cell serving the terminal apparatus 102 is configured as a TDD cell, the detection controller 220 of some example embodiments may, for example, be configured to determine the HA Q timing associated with the cell based at least in part on TDD configuration information that may be included in the received configuration signaling.

[0054] Additionally or alternatively, in some example embodiments, the detection controller 220 may be configured to determine the subset of downlink subframes that potentially include an uplink grant based at least in part on a number of configured HARQ processes for a frame. In embodiments in which the detection controller 220 determines the subset of downlink subframes based at least in part on a number of configured HARQ processes, if a number of uplink grants detected by the detection controller 220 equals the number of configured HARQ processes, the detection controller 220 may determine to not perform further downlink control channel detection for dedicated signaling in the frame even if one or more subframes in the determined subset of subframes remain in the frame (e.g., have not yet occurred).

[0055] Having now described some example methodologies by which a terminal apparatus may determine a subset of subframes within a frame that potentially include an uplink grant based on configuration signaling, an example will be described in the context of time-division duplexed (TDD) cell. In this regard, Table 1 illustrates a series of UL/DL configurations that may be used in a TDD cell, such as a TDD cell implementing an LTE radio access technology. Table 1:

[0056] In the example of Table 2, there are nine subframes per frame. Uplink subframes for a given UL/DL configuration are labeled "UL," and downlink subframes that may potentially include an uplink grant in accordance with various example embodiments are labeled "DL." As an example, assume that TDD configuration 2 is configured in the system 100. There are only two downlink subframes per radio frame that may potentially include an uplink grant— subframe 3 and subframe 8. The detection controller 220 may, for example, determine that only subframes 3 and 8 may potentially include an uplink grant based on the configured TDD configuration (e.g., TDD configuration 2) and the UL HARQ timing.

Accordingly, in this example, the detection controller 220 may be configured to perform downlink control channel detection for dedicated signaling only in subframes 3 and 8. As such, compared to monitoring all downlink subframes in the radio frame in TDD

configuration 2 for an uplink grant, there may be a 75% reduction in performed downlink control channel detection.

[0057] Using the same example of TDD configuration 2, assume that the terminal apparatus 102 has been configured with only 1 HARQ process. In embodiments wherein the detection controller 220 may be configured to determine the subset of subframes that potentially include an uplink grant based at least in part on the number of configured HARQ processes, if an UL grant is detected in subframe 3, then the detection controller may determine to no longer consider subframe 8 as a downlink subframe with a potential uplink grant, thus potentially further reducing an amount of downlink control channel detection performed by a terminal apparatus.

[0058] In some example embodiments, the implicit restriction on the subframes that potentially include an uplink grant may not apply to detection of common control signaling intended for multiple terminals. In this regard, in some example embodiments, the implicit restriction on the subframes that potentially include an uplink grant may only apply to downlink control channel detection for dedicated signaling that may be sent in a terminal- specific (e.g., UE-specific) search space and intended for only the receiving terminal apparatus. Accordingly, downlink control channel detection for common control signaling in a common search space may be performed without restriction as needed. Thus, for example, the implicit restriction on the subframes that potentially include an uplink grant may not apply to detection of PDCCH with SI-RNTI (System Information Radio Network Temporary Identifier), P-RNTI (Paging Radio Network Temporary Identifier), M-RNTI (Multimedia Broadcast Multicast Services Radio Network Temporary Identifier), RA-RNTI (Random Access Radio Network Temporary Identifier), and/or the like that may be used for scrambling common control signaling.

[0059] Some example embodiments provide an extended uplink grant format, which may include an indication of whether a subframe containing the uplink grant also includes a downlink grant. For example, a 1 bit field in an uplink grant may be used to indicate whether the subframe containing the uplink grant also includes a downlink grant. FIG. 4 illustrates an example an example uplink grant format according to some example embodiments, in this regard, in some example embodiments, an uplink grant, such as may be transmitted by an access point 104 to a terminal apparatus 102 on a PDCCH in a downlink subframe, may include a field 402 including the actual uplink grant and a field 404, which may, for example, comprise one or more bits indicating whether the downlink subframe containing the uplink grant also contains a downlink grant.

[0060] In embodiments utilizing an extended uplink grant, such as that illustrated in FIG. 4, if the scheduling controller 318 schedules both an uplink grant and a downlink grant in the same subframe, the scheduling controller 318 may provide an indication in the uplink grant that the subframe also includes a downlink grant. If, however, the subframe only includes an uplink grant, the uplink grant may include an indication that the subframe does not include a downlink grant.

[0061] The detection controller 220 may be configured in embodiments in which extended uplink grants are implemented to determine whether a detected uplink grant indicates that the subframe also includes a downlink grant. If the extended uplink grant indicates that a downlink grant is also included in the same subframe (e.g., if the field 404 indicates that a downlink grant is included in the same subframe), the detection controller 220 may be configured to perform downlink grant detection in the subframe. If, however, the extended uplink grant indicates that a downlink grant is not included in the subframe (e.g., if the field 404 indicates that a downlink grant is not included in the same subframe), the detection controller 220 may be configured to not perform downlink grant detection in the subframe, thereby potentially saving power in an instance in which a downlink grant is not included in the subframe.

[0062] In an instance in which the terminal apparatus 102 has a DRX configuration, the detection controller 220 of some example embodiments may be configured to still perform downlink control channel detection for dedicated signaling only in the subset of subframes within a frame determined to potentially include uplink grants, even if a DRX timer would normally indicate that downlink control channel detection for dedicated signaling should be performed. For example, in some example embodiments, the detection controller 220 may be configured to ignore a DRX timer and determine to not perform downlink control channel detection for dedicated signaling in a subframe that is not in the determined subset of subframes that potentially include an uplink grant even if the DRX timer indicates that the subframe should be monitored for an uplink grant. Thus, using the previously discussed example of TDD configuration 2 described in Table 1, the detection controller 220 may be configured to perform PDCCH detection for dedicated signaling only in subframes 3 and 8, even if a DRX inactivity timer indicates that additional and/or alternative downlink subframes should be monitored.

[0063] As another example, in some example embodiments, the decision controller 220 may be configured to set a DRX timer to ensure that downlink control channel detection for dedicated signaling is performed only in the determined subset of subframes within a frame that potentially include an uplink grant. Thus, again using the example of TDD configuration 2, the detection controller 220 may define the PDCCH subframes as subframes 3 and 8 so that there are only 2 PDCCH subframes per radio frame, and set the DRX timer(s) to count based on this PDCCH subframe definition.

[0064] Some example embodiments provide for a reduced payload size for

acknowledgement/non-acknowledgement (ACK/NACK) feedback that may be sent from a terminal apparatus 102 to an access point 104. In this regard, rather than explicitly tie the ACK/NACK feedback payload size to the TDD configuration, some example embodiments specify the payload size for the ACK/NACK feedback as a fixed 1 bit size and/or based at least in part on a number of subframes in a radio frame that potentially include an uplink grant. For example, in TDD configuration 2, rather than having a 4-bit ACK/NACK feedback payload size (e.g., for subframes 4,5,6, and 8) in subframe 8, only a single bit may be used for a feedback payload in accordance with some example embodiments to provide feedback only for subframe 8. Accordingly, in some example embodiments, the detection controller 220 may be configured to specify and the scheduling controller 318 may be configured to expect the appropriate reduced feedback payload size.

[0065] FIG. 5 illustrates a flowchart according to an example method for performing downlink control channel detection according to some example embodiments. In this regard, FIG. 5 illustrates operations that may be performed at a terminal apparatus 202. The operations illustrated in and described with respect to FIG. 5 may, for example, be performed by, with the assistance of, and/or under the control of one or more of the processing circuitry 210, processor 212, memory 214, communication interface 218, or detection controller 220. Operation 500 may comprise determining, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink. The processing circuitry 210, processor 212, memory 214, communication interface 218, and/or detection controller 220 may, for example, provide means for performing operation 500. Operation 510 may comprise performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant. The processing circuitry 210, processor 212, memory 214, communication interface 218, and/or detection controller 220 may, for example, provide means for performing operation 10.

[0066] FIG. 6 illustrates a flowchart according to an example method for facilitating downlink control channel detection according to some example embodiments. In this regard, FIG. 6 illustrates operations that may be performed at an access point apparatus 302. The operations illustrated in and described with respect to FIG. 6 may, for example, be performed by, with the assistance of, and/or under the control of one or more of the processing circuitry 310, processor 312, memory 314, communication interface 316, or scheduling controller 318. Operation 600 may comprise defining a configuration signaling including information enabling a terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant. The processing circuitry 310, processor 312, memory 314, communication interface 316, and/or scheduling controller 318 may, for example, provide means for performing operation 600. Operation 610 may comprise scheduling an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes. The processing circuitry 310, processor 312, memory 314, communication interface 316, and/or scheduling controller 318 may, for example, provide means for performing operation 610.

[0067] FIGS. 5-6 are flowcharts of a system, method and program product according to example embodiments of the invention. It will be understood that each block of the flowcharts, and combinations of blocks in the flowcharts, may be implemented by various means, such as hardware, firmware, processor, circuitry and/or other device associated with execution of software including one or more computer program instructions. For example, one or more of the procedures described above may be embodied by computer program instructions. In this regard, the computer program instructions which embody the procedures described above may be stored by a memory device of an apparatus employing an

embodiment of the present invention and executed by a processor in the apparatus. As will be appreciated, any such computer program instructions may be loaded onto a computer or other programmable apparatus (e.g., hardware) to produce a machine, such that the resulting computer or other programmable apparatus provides for implementation of the functions specified in the flowcharts block(s). These computer program instructions may also be stored in a non-transitory computer-readable storage memory that may direct a computer or other programmable apparatus to function in a particular manner, such that the instructions stored in the computer-readable storage memory produce an article of manufacture the execution of which implements the function specified in the flowcharts block(s). The computer program instructions may also be loaded onto a computer or other programmable apparatus to cause a series of operations to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide operations for implementing the functions specified in the flowcharts block(s).

[0068] Accordingly, blocks of the flowcharts support combinations of means for performing the specified functions and combinations of operations for performing the specified functions. It will also be understood that one or more blocks of the flowcharts, and combinations of blocks in the flowcharts, can be implemented by special purpose hardware- based computer systems which perform the specified functions, or combinations of special purpose hardware and computer instructions.

[0069] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and/or functions, it should be appreciated that different

combinations of elements and/or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and/or functions than those explicitly described above are also contemplated as may be set forth in some of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

WHAT IS CLAIMED IS:

1. A method comprising:

determining, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant; and

performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant.

2. The method of Claim 1, wherein determining the subset of downlink subframes that potentially include an uplink grant comprises determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a hybrid automatic repeat request (HARQ) timing associated with a serving cell,

3. The method of any of Claims 1 to 2, wherein determining the subset of downlink subframes that potentially include an uplink grant comprises determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a number of configured uplink hybrid automatic repeat request (HARQ) processes.

4. The method of Claim 3, further comprising, in an instance in which a number of uplink grants equal to the number of configured HARQ processes has been detected and one or more subframes in the determined subset of subframes that potentially include an uplink grant remain in the frame, determining to not perform downlink control channel detection for dedicated signaling in the one or more subframes in the determined subset of subframes that remain in the frame.

5. The method of any of Claims 1 to 4, further comprising, for a subframe in which downlink control channel detection is performed:

determining whether an uplink grant included in the subframe includes an indication that the subframe also includes a downlink grant; and

in an instance in which it is determined that the uplink grant included in the subframe includes an indication that the subframe also includes a downlink grant, performing detection of the downlink grant in the subframe.

6. The method of any of Claims 1 to 5, wherein: determining a subset of downlink subframes that potentially include an uplink grant comprises determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration; and performing downlink control channel detection for dedicated signaling comprises performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant even if a DRX timer indicates that a subframe that is not in the determined subset of subframes should be monitored for an uplink grant.

7. The method of any of Claims 1 to 5, wherein determining a subset of downlink subframes that potentially include an uplink grant comprises determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration, the method further comprising:

setting a DRX timer to ensure that downlink control channel detection for dedicated signaling is performed only in the determined subset of subframes that potentially include an uplink grant.

8. The method of any of Claims 1 to 7, wherein a size of an

acknowledgement/non-acknowledgement (ACK/NAC ) feedback payload for uplink feedback is set to be 1 bit.

9. The method of any of Claims 1 to 8, wherein a size of an ACK NACK feedback payload for uplink feedback is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant,

10. The method of any of Claims 1 to 9, wherein performing downlink control channel detection for dedicated signaling comprises performing physical downlink control channel (PDCCH) detection for dedicated signaling at a user equipment (UE) served by an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network.

1 1. An apparatus comprising:

at least one processor; and

at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least:

determine, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant; and

perform downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant.

12. The apparatus of Claim 11 , wherein the. at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to determine the subset of downlink subframes that potentially include an uplink grant at least in part by determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a hybrid automatic repeat request (HARQ) timing associated with a serving cell.

13. The apparatus of any of Claims 11 to 12, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to determine the subset of downlink subframes that potentially include an uplink grant at least in part by determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a number of configured uplink hybrid automatic repeat request (HARQ) processes.

14. The apparatus of Claim 13, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus, in an instance in which a number of uplink grants equal to the number of configured HARQ processes has been detected and one or more subframes in the determined subset of subframes that potentially include an uplink grant remain in the frame, to not perform downlink control channel detection for dedicated signaling in the one or more subframes in the determined subset of subframes that remain in the frame.

15. The apparatus of any of Claims 1 1 to 14, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus, for a subframe in which downlink control channel detection is performed, to: determine whether an uplink grant included in the subframe includes an indication that the subframe also includes a downlink grant; and in an instance in which it is determined that the uplink grant included in the subframe includes an indication that the subf ame also includes a downlink grant, perform detection of the downlink grant in the subframe.

16. The apparatus of any of Claims 1 1 to 15, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to:

determine a subset of downlink subframes that potentially include an uplink grant at least in part by determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration; and perform downlink control channel detection for dedicated signaling at least in part by performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant even if a DRX timer indicates that a subframe that is not in the determined subset of subframes should be monitored for an uplink grant.

17. The apparatus of any of Claims Π to 15, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to:

determine a subset of downlink subframes that potentially include an uplink grant at least in part by determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration; and set a DRX timer to ensure that downlink control channel detection for dedicated signaling is performed only in the determined subset of subframes that potentially include an uplink grant.

18. The apparatus of any of Claims 11 to 17, wherein a size of an

acknowledgement/non-acknowledgement (ACK/NACK) feedback payload for uplink feedback is set to be 1 bit.

19. The apparatus of any of Claims 1 1 to 18, wherein a size of an ACK/NACK feedback payload for uplink feedback is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant.

20. The apparatus of any of Claims 11 to 19, wherein the apparatus is implemented on a user equipment (UE) served by an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network, and wherein at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to perform downlink control channel detection for dedicated signaling at least in part by performing physical downlink control channel (PDCCH) detection for dedicated signaling.

21. The apparatus of any of Claims 11 to 20, wherein the apparatus is

implemented on a mobile phone, the mobile phone comprising:

user interface circuitry; and

user interface software arranged to facilitate user control of at least some functions of the mobile phone through use of a display.

22. A computer program product comprising:

at least one non-transitory computer readable medium having program code instructions stored thereon, the program code instructions comprising instructions, which when performed by an apparatus, are configured to cause the apparatus to at least:

23. The computer program product of Claim 22, wherein the program code instructions further comprise instructions configured to cause the apparatus to determine the subset of downlink subframes that potentially include an uplink grant at least in part by determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a hybrid automatic repeat request (HARQ) timing associated with a serving cell.

24. The computer program product of any of Claims 22 to 23, wherein the program code instructions further comprise instructions configured to cause the apparatus to determine the subset of downlink subframes that potentially include an uplink grant at least in part by determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a number of configured uplink hybrid automatic repeat request (HARQ) processes.

25. The computer program product of Claims 24, wherein the program code instructions further comprise instructions configured to cause the apparatus, in an instance in which a number of uplink grants equal to the number of configured HARQ processes has been detected and one or more subframes in the determined subset of subframes that potentially include an uplink grant remain in the frame, to not perform downlink control channel detection for dedicated signlaing in the one or more subframes in the determined subset of subframes that remain in the frame.

26. The computer program product of any of Claims 22 to 25, wherein the program code instructions further comprise instructions configured to cause the apparatus, for a subfrarne in which downlink control channel detection is performed, to:

determine whether an uplink grant included in the subfrarne includes an indication that the subfrarne also includes a downlink grant; and

in an instance in which it is determined that the uplink grant included in the subfrarne includes an indication that the subfrarne also includes a downlink grant, perform detection of the downlink grant in the subfrarne.

27. The computer program product of any of Claims 22 to 26, wherein the program code instructions further comprise instructions configured to cause the apparatus to: determine a subset of downlink subframes that potentially include an uplink grant at least in part by determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration; and perform downlink control channel detection for dedicated signaling at least in part by performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant even if a DRX timer indicates that a subfrarne that is not in the determined subset of subframes should be monitored for an uplink grant.

28. The computer program product of any of Claims 22 to 26, wherein the program code instructions further comprise instructions configured to cause the apparatus to: determine a subset of downlink subframes that potentially include an uplink grant at least in part by determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration; and set a DRX timer to ensure that downlink control channel detection for dedicated signaling is performed only in the determined subset of subframes that potentially include an uplink grant.

29. The computer program product of any of Claims 22 to 28, wherein a size of an acknowledgement/non-acknowledgement (ACK/NACK) feedback payload for uplink feedback is set to be 1 bit.

30. The computer program product of any of Claims 22 to 29, wherein a size of an ACK/NACK feedback payload for uplink feedback is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant.

31. The computer program product of any of Claims 22 to 30, wherein the program code instructions further comprise instructions configured to cause the apparatus to perform downlink control channel detection for dedicated signaling at least in part by performing physical downlink control channel (PDCCH) detection for dedicated signaling at a user equipment (UE) served by an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network.

32. An apparatus comprising:

means for determining, based at least in part on received configuration signaling, a subset of downlink subframes within a frame that potentially include an uplink grant; and means for performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant.

33. The apparatus of Claim 32, wherein the means for determining the subset of downlink subframes that potentially include an uplink grant comprises means for determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a hybrid automatic repeat request (HARQ) timing associated with a serving cell.

34. The apparatus of any of Claims 32 to 33, wherein the means for determining the subset of downlink subframes that potentially include an uplink grant comprises means for determining the subset of downlink subframes that potentially include an uplink grant based at least in part on a number of configured uplink hybrid automatic repeat request (HARQ) processes.

35. The apparatus of Claim 34, further comprising means for, in an instance in which a number of uplink grants equal to the number of configured HARQ processes has been detected and one or more subframes in the determined subset of subframes that potentially include an uplink grant remain in the frame, determining to not perform downlink control channel detection for dedicated signaling in the one or more subframes in the determined subset of subframes that remain in the frame.

36. The apparatus of any of Claims 32 to 35, further comprising, for a subframe in which downlink control channel detection is performed:

means for determining whether an uplink grant included in the subframe includes an indication that the subframe also includes a downlink grant; and

means for, in an instance in which it is determined that the uplink grant included in the subframe includes an indication that the subframe also includes a downlink grant, performing detection of the downlink grant in the subframe.

37. The apparatus of any of Claims 32 to 36, wherein;

the means for determining a subset of downlink subframes that potentially include an uplink grant comprises means for determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration; and

the means for performing downlink control channel detection for dedicated signaling comprises means for performing downlink control channel detection for dedicated signaling only in the determined subset of subframes that potentially include an uplink grant even if a DRX timer indicates that a subframe that is not in the determined subset of subframes should be monitored for an uplink grant.

38. The apparatus of any of Claims 32 to 36, wherein the means for determining a subset of downlink subframes that potentially include an uplink grant comprises means for determining a subset of downlink subframes that potentially include an uplink grant for a terminal apparatus having a discontinuous reception (DRX) configuration, the apparatus further comprising:

means for setting a DRX timer to ensure that downlink control channel detection for dedicated signaling is performed only in the determined subset of subframes that potentially include an uplink grant.

39. The apparatus of any of Claims 32 to 38, wherein a size of an

40. The apparatus of any of Claims 32 to 39, wherein a size of an ACK/NACK feedback payload for uplink feedback is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant.

4 . The apparatus of any of Claims 32 to 40, wherein the apparatus is

implemented on a user equipment (UE) served by an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network, and wherein the means for performing downlink control channel detection for dedicated signaling comprises means for performing physical downlink control channel (PDCCH) for dedicated signaling.

42. A method comprising:

defining a configuration signaling for sending to a terminal apparatus, the configuration signaling including information enabling the terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant; and scheduling an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes.

43. The method of Claim 42, wherein scheduling an uplink grant for the terminal apparatus comprises scheduling an uplink grant for transmission on a downlink control channel in a downlink subframe in the subset of downlink subframes.

44. The method of any of Claims 42 to 43, wherein a size of an

acknowledgement/non-acknowledgement (AC /NACK) feedback payload for uplink feedback expected from the terminal apparatus is set to be 1 bit.

45. The method of any of Claims 42 to 44, wherein a size of an ACK/NACK feedback payload for uplink feedback expected from the terminal apparatus is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant.

46. The method of any of Claims 42 to 45, wherein scheduling an uplink grant for the terminal apparatus comprises scheduling, at an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network, an uplink grant for a user equipment (UE) on a physical downlink control channel (PDCCH) in a downlink subframe in the subset of downlink subframes.

47. An apparatus comprising:

at least one processor; and

at least one memory including computer program code,

the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least:

define a configuration signaling for sending to a terminal apparatus, the configuration signaling including information enabling the terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant; and

schedule an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes.

48. The apparatus of Claim 47, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to schedule an uplink grant for the terminal apparatus at least in part by scheduling an uplink grant for transmission on a downlink control channel in a downlink subframe in the subset of downlink subframes.

49. The apparatus of any of Claims 47 to 48, wherein a size of an

50. The apparatus of any of Claims 47 to 49, wherein a size of an ACK/NACK feedback payload for uplink feedback expected from the terminal apparatus is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant.

51. The apparatus of any of Claims 47 to 50, wherein the apparatus is

implemented on an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network, and wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to schedule an uplink grant for the terminal apparatus at least in part by scheduling an uplink grant for a user equipment (UE) on a physical downlink control channel (PDCCH) in a downlink subframe in the subset of downlink subframes.

52. A computer program product comprising:

at least one non-transitory computer readable medium having program code instructions stored thereon, the program code comprising instructions, which when performed by an apparatus, are configured to cause the apparatus to at least:

schedule an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes,

53. The computer program product of Claim 52, wherein the program code instructions further comprises instructions configured to cause the apparatus to schedule an uplink grant for the terminal apparatus at least in part by scheduling an uplink grant for transmission on a downlink control channel in a downlink subframe in the subset of downlink subframes.

54. The computer program product of any of Claims 52 to 53, wherein a size of an acknowledgement/non-acknowledgement (ACK/NACK) feedback payload for uplink feedback expected from the terminal apparatus is set to be 1 bit.

55. The computer program product of any of Claims 52 to 54, wherein a size of an ACK/NACK feedback payload for uplink feedback expected from the terminal apparatus is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant.

56. The computer program product of any of Claims 52 to 55, wherein the program code instructions further comprise instructions configured to cause the apparatus to schedule an uplink grant for the terminal apparatus at least in part by scheduling, at an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network, an uplink grant for a user equipment (UE) on a physical downlink control channel (PDCCH) in a downlink subframe in the subset of downlink subframes.

57. An apparatus comprising:

means for defining a configuration signaling for sending to a terminal apparatus, the configuration signaling including information enabling the terminal apparatus to determine a subset of downlink subframes within a frame that potentially include an uplink grant; and means for scheduling an uplink grant for the terminal apparatus only in a downlink subframe in the subset of downlink subframes.

58. The apparatus of Claim 57, wherein the means for scheduling an uplink grant for the terminal apparatus comprises means for scheduling an uplink grant for transmission on a downlink control channel in a downlink subframe in the subset of downlink subframes.

59. The apparatus of any of Claims 57 to 58, wherein a size of an

acknowledgement/non-acknowledgement (ACK/NACK) feedback payload for uplink feedback expected from the terminal apparatus is set to be 1 bit.

60. The apparatus of any of Claims 57 to 59, wherein a size of an ACK/NACK feedback payload for uplink feedback expected from the terminal apparatus is defined based at least in part on a number of subframes in the subset of downlink subframes that potentially include an uplink grant.

61. The apparatus of any of Claims 57 to 60, wherein the apparatus is

implemented on an evolved Node B (eNB) of a Long Term Evolution (LTE) cellular network, and wherein the means for scheduling an uplink grant for the terminal apparatus comprises means for scheduling an uplink grant for a user equipment (UE) on a physical downlink control channel (PDCCH) in a downlink subframe in the subset of downlink subframes.