Patent Description:
Document <NPL>) discloses another example of the prior art.

Document <CIT> discloses another example of the prior art.

The embodiments of the disclosure will be understood more fully from the detailed description given below and from the accompanying drawings of various embodiments of the disclosure. However, while the drawings are to aid in explanation and understanding, they are only an aid, and should not be taken to limit the disclosure to the specific embodiments depicted therein.

A variety of wireless cellular communication systems have been implemented, including a 3rd Generation Partnership Project (3GPP) Universal Mobile Telecommunications System, a 3GPP Long-Term Evolution (LTE) system, and a 3GPP LTE-Advanced (LTE-A) system. Next-generation wireless cellular communication systems based upon LTE and LTE-A systems are being developed, such as a fifth generation (<NUM>) wireless system / <NUM> mobile networks system.

The sizeable growth in wireless traffic has led to an urgent need of rate improvement. With mature physical layer designs, further improvements in spectral efficiency may be marginal. Meanwhile, a scarcity of licensed spectrum in low frequency bands may result in a deficit in data rate increases. Thus, there is increasing interest in the operation of LTE systems in unlicensed spectrum.

As a result, one major enhancement for LTE has been to enable its operation with focus on Downlink (DL) transmission in unlicensed spectrum via Licensed-Assisted Access (LAA), which may expand system bandwidths by utilizing a flexible carrier aggregation (CA) framework introduced for LTE-Advanced systems. Enhanced operation of LTE systems in unlicensed spectrum may be supported in future releases and <NUM> systems. LTE operation in unlicensed spectrum may include Uplink (UL) transmissions for CA based LAA systems, LTE operation in unlicensed spectrum via dual connectivity (DC), and/or standalone LTE operation systems in unlicensed spectrum.

In some embodiments, LTE-based technology may operate solely in unlicensed spectrum without requiring an "anchor" in licensed spectrum, such as in MulteFire™ technology by MulteFire Alliance of Fremont California, USA. Such operation may require little to no assistance from licensed-spectrum devices, and may be amenable to lean, self-contained network architectures suitable for neutral deployments where a wide variety of deployments can service a wide variety of devices. Standalone LTE operation in unlicensed spectrum may also combine performance benefits of LTE technology with a relative simplicity of Wi-Fi-like deployments. Standalone LTE operation may accordingly be a significantly important technology in meeting demands of ever-increasing wireless traffic.

An unlicensed frequency band of current interest is the <NUM> band, which has wide spectrum with global common availability. The <NUM> band in the US may be governed by Unlicensed National Information Infrastructure (U-NII) rules promulgated by the Federal Communications Commission (FCC). The main incumbent systems in the <NUM> band are Wireless Local Area Networks (WLAN) systems, specifically those based on Institute of Electrical and Electronics Engineers (IEEE) <NUM> a/n/ac technologies.

Since WLAN systems may be deployed both by individuals and operators for carrier-grade access service and data offloading, care should be taken before deployment of competing systems. Listen-Before-Talk (LBT) may be employed in future LTE LAA systems to promote fair coexistence with incumbent systems (e.g., WLAN systems). LBT is a procedure whereby a radio transmitter may first sense a medium, then transmit if the medium is sensed to be idle.

Although LBT may generally be employed before transmissions in unlicensed spectrum, LBT may be skipped when multiple contiguous UL subframes are scheduled to the same set of UEs, and when the UEs have performed an LBT successfully in the preceding subframe (e.g., an LBT that determined the unlicensed spectrum to be idle). In various embodiments, transmissions over multiple contiguous subframes may be considered to be a continuous UL transmission burst.

If adjacent subframes are scheduled to different UEs, a system may be disposed to perform an LBT. Either the first symbol in a scheduled subframe or the last symbol of a preceding subframe may be punctured for performing an LBT. An eNB may indicate whether a puncturing is needed and/or whether an LBT should be performed for the UL subframes (via, e.g., common Physical Downlink Control Channel (PDCCH)).

Discussed herein are scenarios in which multiple contiguous UL subframes are scheduled to the same UEs. In some embodiments, an eNB may indicate (e.g., to one or more UEs) that puncturing and/or LBT should be performed for the first of the contiguous subframes. Also discussed herein are scenarios in which LBT is performed in the subframes other than the indicated first subframe when the LBT in the first subframe fails.

Note that an eNB may not know a priori whether an LBT at a first subframe among contiguous subframes has succeeded or not. Accordingly, also discussed herein are methods for an eNB to determine a starting position of received subframes.

In various frame structures, a DL burst may be preceded by a legacy LTE LBT. In addition, UL control signals may be dynamically transmitted via a short extended Physical Uplink Control Channel (short ePUCCH, or sPUCCH) or a long ePUCCH. As a result, also discussed herein are details of channel access procedures of various UL transmissions.

In the following description, numerous details are discussed to provide a more thorough explanation of embodiments of the present disclosure. It will be apparent to one skilled in the art, however, that embodiments of the present disclosure may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form, rather than in detail, in order to avoid obscuring embodiments of the present disclosure.

Throughout the specification, and in the claims, the term "connected" means a direct electrical, mechanical, or magnetic connection between the things that are connected, without any intermediary devices. The term "coupled" means either a direct electrical, mechanical, or magnetic connection between the things that are connected or an indirect connection through one or more passive or active intermediary devices. The term "circuit" or "module" may refer to one or more passive and/or active components that are arranged to cooperate with one another to provide a desired function. The term "signal" may refer to at least one current signal, voltage signal, magnetic signal, or data/clock signal. The meaning of "a," "an," and "the" include plural references. The meaning of "in" includes "in" and "on.

The terms "substantially," "close," "approximately," "near," and "about" generally refer to being within +/- <NUM>% of a target value. Unless otherwise specified the use of the ordinal adjectives "first," "second," and "third," etc., to describe a common object, merely indicate that different instances of like objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein.

For purposes of the embodiments, the transistors in various circuits, modules, and logic blocks are Tunneling FETs (TFETs). Some transistors of various embodiments may comprise metal oxide semiconductor (MOS) transistors, which include drain, source, gate, and bulk terminals. The transistors may also include Tri-Gate and FinFET transistors, Gate All Around Cylindrical Transistors, Square Wire, or Rectangular Ribbon Transistors or other devices implementing transistor functionality like carbon nanotubes or spintronic devices. MOSFET symmetrical source and drain terminals i.e., are identical terminals and are interchangeably used here. A TFET device, on the other hand, has asymmetric Source and Drain terminals. Those skilled in the art will appreciate that other transistors, for example, Bi-polar junction transistors-BJT PNP/NPN, BiCMOS, CMOS, etc., may be used for some transistors without departing from the scope of the disclosure.

For the purposes of the present disclosure, the phrases "A and/or B" and "A or B" mean (A), (B), or (A and B).

In addition, for purposes of the present disclosure, the term "eNB" may refer to a legacy LTE capable Evolved Node-B (eNB), a Narrowband Internet-of-Things (NB-IoT) capable eNB, a Cellular Internet-of-Things (CIoT) capable eNB, a Machine-Type Communication (MTC) capable eNB, and/or another base station for a wireless communication system. For purposes of the present disclosure, the term "UE" may refer to a legacy LTE capable User Equipment (UE), an NB-IoT capable UE, a CIoT capable UE, an MTC capable UE, and/or another mobile equipment for a wireless communication system.

Various embodiments of eNBs and/or UEs discussed below may process one or more transmissions of various types. Some processing of a transmission may comprise demodulating, decoding, detecting, parsing, and/or otherwise handling a transmission that has been received. In some embodiments, an eNB or UE processing a transmission may determine or recognize the transmission's type and/or a condition associated with the transmission. For some embodiments, an eNB or UE processing a transmission may act in accordance with the transmission's type, and/or may act conditionally based upon the transmission's type. An eNB or UE processing a transmission may also recognize one or more values or fields of data carried by the transmission. Processing a transmission may comprise moving the transmission through one or more layers of a protocol stack (which may be implemented in, e.g., hardware and/or software-configured elements), such as by moving a transmission that has been received by an eNB or a UE through one or more layers of a protocol stack.

Various embodiments of eNBs and/or UEs discussed below may also generate one or more transmissions of various types. Some generating of a transmission may comprise modulating, encoding, formatting, assembling, and/or otherwise handling a transmission that is to be transmitted. In some embodiments, an eNB or UE generating a transmission may establish the transmission's type and/or a condition associated with the transmission. For some embodiments, an eNB or UE generating a transmission may act in accordance with the transmission's type, and/or may act conditionally based upon the transmission's type. An eNB or UE generating a transmission may also determine one or more values or fields of data carried by the transmission. Generating a transmission may comprise moving the transmission through one or more layers of a protocol stack (which may be implemented in, e.g., hardware and/or software-configured elements), such as by moving a transmission to be sent by an eNB or a UE through one or more layers of a protocol stack.

<FIG> illustrates a scenario of Listen-Before-Talk (LBT) gaps within Uplink (UL) subframes, in accordance with some embodiments of the disclosure. A scenario <NUM> may comprise a first case <NUM> and a second case <NUM>. In first case <NUM>, an initial symbol (e.g., a symbol number <NUM>) of a subframe scheduled for a UE for UL transmission (for, e.g., Physical Uplink Shared Channel (PUSCH) transmission) may be punctured for LBT. In second case <NUM>, a last symbol (e.g., a symbol number <NUM>) of a subframe previous to a subframe scheduled for a UE for UL transmission (for, e.g., PUSCH transmission) may be punctured for LBT.

First case <NUM> may comprise a set of DL subframes <NUM> (which may be transmitted by an eNB), a set of UL subframes <NUM> (which may be transmitted by one or more UEs), and a transition period <NUM> between DL subframes <NUM> and UL subframes <NUM>. DL subframes <NUM> may carry PDCCH. Transition period <NUM> may comprise at least a portion of a DL subframe, followed by a potential gap for switching between transmission and reception and/or for LBT, followed by an sPUCCH (which may carry UL control).

One or more DL subframes <NUM> may carry PDCCH that comprise a first indication <NUM> and/or a second indication <NUM>. In accordance with first indication <NUM>, an initial symbol (e.g., a symbol number <NUM>) of a UL subframe <NUM> may be indicated for a puncturing and/or for an LBT gap. In accordance with second indication <NUM>, an initial symbol (e.g., a symbol number <NUM>) of another UL subframe <NUM> may be indicated for no puncturing and/or for no LBT gap.

Second case <NUM> may comprise a set of DL subframes <NUM> (which may be transmitted by an eNB), a set of UL subframes <NUM> (which may be transmitted by one or more UEs), and a transition period <NUM> between DL subframes <NUM> and UL subframes <NUM>. DL subframes <NUM> may carry PDCCH. Transition period <NUM> may comprise at least a portion of a DL subframe, followed by a potential gap for switching between transmission and reception and/or for LBT, followed by an sPUCCH (which may carry UL control).

One or more DL subframes <NUM> may carry PDCCH that comprise a first indication <NUM> and/or a second indication <NUM>. In accordance with first indication <NUM>, a last symbol (e.g., a symbol number <NUM>) of a UL subframe <NUM> may be indicated for a puncturing and/or for an LBT gap. In accordance with second indication <NUM>, a last symbol (e.g., a symbol number <NUM>) of another UL subframe <NUM> subframe may be indicated for no puncturing and/or for no LBT gap.

According to the invention, when multiple contiguous UL subframes are scheduled to the same UEs, an eNB indicates to puncture the first symbol in the initial subframe of the contiguous subframes, or - in other examples not covered by the claims - the last symbol in a subframe preceding the contiguous subframes.

<FIG> illustrates a scenario of LBT methods. A scenario <NUM> may comprise a first case <NUM> and a second case <NUM>. In first case <NUM>, according to the invention, an initial symbol (e.g., a symbol number <NUM>) of a subframe scheduled for a UE for UL transmission (for, e.g., PUSCH transmission) is punctured for LBT. In second case <NUM> not covered by the claims, a last symbol (e.g., a symbol number <NUM>) of a subframe previous to a subframe for a UE for UL transmission (for, e.g., PUSCH transmission) may be punctured for LBT.

One or more DL subframes <NUM> may carry PDCCH that comprise a first indication <NUM> and/or a second indication <NUM>. In accordance with first indication <NUM>, an initial symbol (e.g., a symbol number <NUM>) of a UL subframe <NUM> is indicated for a puncturing and/or for an LBT gap. In accordance with second indication <NUM>, an initial symbol (e.g., a symbol number <NUM>) of another UL subframe <NUM> may be indicated for no puncturing and/or for no LBT gap.

In first case <NUM>, an LBT due to first indication <NUM> has determined that the unlicensed spectrum was busy (e.g., the LBT failed). Subsequently, subframe <NUM> may comprise a plurality of time indices corresponding to potential opportunities for one or more subsequent LBTs.

In second case <NUM>, an LBT due to second indication <NUM> has determined that the unlicensed spectrum was busy (e.g., the LBT failed). Subsequently, subframe <NUM> may comprise a plurality of time indices corresponding to potential opportunities for one or more subsequent LBTs.

In various embodiments, a UE may adopt different LBT methods if an indicated LBT for transmission of a subframe within contiguous subframes fails (e.g., determines the unlicensed spectrum to be busy). In some embodiments, a no-puncturing and/or no-LBT indication from an eNB may be overridden by a UE, and puncturing and/or LBT may still be performed.

As depicted for example in <FIG>, for some embodiments, after an LBT fails in a subframe preceding a subframe in which the UE is scheduled to transmit, LBT may be performed multiple times until it succeeds (e.g., the unlicensed spectrum is determined to be idle), or until the end of the contiguous UL subframes scheduled to the UE.

In some embodiments, if an end of a successful LBT and a following subframe boundary are not aligned, the UE may transmit a signal. For some such embodiments, the UE may transmit a reservation signal, or another useful signal such as a Sounding Reference Signal (SRS) or a Demodulation Reference Signal (DMRS). The signal may be transmitted within a duration between the successful LBT and the following subframe boundary. For some such embodiments, a reservation signal or another useful signal such as SRS or DMRS may not be transmitted within the duration between the successful LBT and the following subframe boundary.

In some embodiments, a number of LBT trials may be limited by a fixed parameter (e.g., a predetermined parameter), or by a configurable parameter.

<FIG> illustrates a scenario of performing LBT. A scenario <NUM> may comprise a first case <NUM> and a second case <NUM>. In first case <NUM>, an initial symbol (e.g., a symbol number <NUM>) of a subframe scheduled for a UE for UL transmission (for, e.g., PUSCH transmission) is punctured for LBT. In second case <NUM> not covered by the claims, a last symbol (e.g., a symbol number <NUM>) of a subframe previous to a subframe for a UE for UL transmission (for, e.g., PUSCH transmission) may be punctured for LBT.

One or more DL subframes <NUM> may carry PDCCH that comprise a first indication <NUM> and/or a second indication <NUM>. In accordance with first indication <NUM>, an initial symbol (e.g., a symbol number <NUM>) of a UL subframe <NUM> is indicated for a puncturing and/or for an LBT gap. In accordance with second indication <NUM>, an initial symbol <NUM> (e.g., a symbol number <NUM>) of another UL subframe <NUM> may be indicated for no puncturing and/or for no LBT gap.

In first case <NUM>, an LBT due to first indication <NUM> has determined that the unlicensed spectrum was busy (e.g., the LBT failed). Subsequently, a UE may treat first symbol <NUM> as a potential opportunity for an LBT.

One or more DL subframes <NUM> may carry PDCCH that comprise a first indication <NUM> and/or a second indication <NUM>. In accordance with first indication <NUM>, a last symbol (e.g., a symbol number <NUM>) of a UL subframe <NUM> may be indicated for a puncturing and/or for an LBT gap. In accordance with second indication <NUM>, a last symbol <NUM> (e.g., a symbol number <NUM>) of another UL subframe <NUM> subframe may be indicated for no puncturing and/or for no LBT gap.

In second case <NUM>, an LBT due to first indication <NUM> has determined that the unlicensed spectrum was busy (e.g., the LBT failed). Subsequently, a UE may treat last symbol <NUM> as a potential opportunity for an LBT.

A UE may wait until a following subframe boundary, or until one symbol before a following subframe boundary, to perform LBT.

As discussed herein, an eNB may not know a priori whether an LBT at a first subframe among contiguous subframes has succeeded or not. If the LBT for the first subframe among contiguous subframes scheduled to the same UEs succeeds, the eNB knows the starting position of the first subframe, and the following subframes start from the first symbol. On the other hand, if the LBT for the first subframe among these contiguous subframes fails, LBT may be performed for the transmission in the following subframes, and the first symbol of the following subframes may be punctured for LBT.

In various embodiments, an eNB may employ different methods to determine a starting position of the subframes other than the first subframe. In some embodiments, blind detection may be used, and the eNB may perform a first hypothesis test and a second hypothesis test (which may respectively correspond to a case starting from a first symbol and a case starting from a second symbol).

For some embodiments, an eNB may employ DMRS-based detection. In some embodiments, a location of a DMRS may be changed to be the first symbol, or an additional DMRS may be transmitted in the first symbol of the UL subframe. The eNB may then detect the presence of DMRS in the first symbol to determine the starting position. In some embodiments, different DMRS sequences may be used to indicate the starting position.

In some embodiments, DMRS may be modulated with a phase shift to include one bit of information for the indication of starting symbol. For example, denoting the current DMRS to be x, then x may be transmitted if the subframe starts from the first symbol, while -x may be transmitted if the subframe starts from the second symbol. In some embodiments, a <NUM> degree shift may differentiate a phase shift corresponding to the first symbol from a phase shift corresponding to the second symbol.

In some embodiments, an eNB may rely on the presence of signal in a preceding subframe. If a transmission from the same UE in the preceding subframe is detected to be present, the eNB may assume the current subframe starts from the first symbol. Otherwise the eNB may assume the current subframe starts from the second symbol.

Note that an eNB may determine the starting position of a subframe based on the methods discussed herein, but the eNB may still not know if the UE transmits on the subframe or not. Additional signal presence detection may accordingly be performed, such as blind detection including hypothesis testing of whether or not the signal is transmitted, or DRMS based signal presence detection.

Moreover, in various embodiments, any combinations of the above methods are possible.

<FIG> illustrates a scenario of a frame structure, in accordance with some embodiments of the disclosure. A scenario may comprise a set of subframes <NUM>, which may in turn comprise a set of DL subframes <NUM> (which may be transmitted by an eNB), a set of UL subframes <NUM> (which may be transmitted by one or more UEs), and a transition period <NUM> between DL subframes <NUM> and UL subframes <NUM>. Transition period <NUM> may comprise at least a portion of a DL subframe (which may span a Downlink Pilot Time Slot (DwPTS)), followed by a potential gap for switching between transmission and reception and Clear Channel Assessment (CCA) or a short LBT, followed by an sPUCCH (which may span between one and four Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols).

One or more DL subframes <NUM> may carry PDCCH that comprise an indication <NUM>. In accordance with indication <NUM>, a long ePUCCH <NUM> may be triggered (potential gap for switching between transmission and reception and CCA or a short LBT). Long ePUCCH <NUM> may be triggered following a gap <NUM> after UL subframes <NUM>.

Accordingly, a DL burst may be preceded by a regular LBT. UL control signals may be dynamically transmitted via an sPUCCH format consisting of the final n symbols of a subframe (which may be chose to be between one and four). The other symbols of the subframe before the n symbols (e.g., the first ten symbols in a fourteen-symbol subframe) may be used for transmissions other than UL transmission (e.g., DL subframe transmissions).

For some embodiments, UL control signals may be transmitted by a long ePUCCH, which may be triggered by an eNB, and which may be frequency domain multiplexed with PUSCH. In some embodiments, a transmitting node may be disposed to performing an LBT procedure.

In various embodiments, different options for LBT may be employed for UL control signals (for, e.g., sPUCCH transmission, long ePUCCH transmission, and/or SRS transmission). In some embodiments, if an sPUCCH transmission (or a long ePUCCH transmission, or an SRS transmission) occupies less than five percent of a duty cycle over <NUM> milliseconds (ms), LBT might not be considered according to regulations.

For some embodiments, an sPUCCH transmission (or a long ePUCCH transmission, or an SRS transmission) may be preceded by a short LBT (e.g., an LBT performed for duration of <NUM> microseconds (µs), or a single interval LBT) right before the transmission of sPUCCH. If the single interval LBT is not performed right before the sPUCCH transmission, then a reservation signal may be transmitted to align with the sPUCCH symbol boundary.

In some embodiments, the LBT procedure may be similar to an LBT for PUSCH (e.g. a Category <NUM> LBT).

Meanwhile, in order to avoid collisions with other ongoing transmissions, it may be advantageous for an SRS transmission from a UE to be preceded by an LBT unless the UE is already transmitting. In various embodiments, different methods of SRS transmission may be employed. In some embodiments, SRS may be transmitted in a last symbol of a UL subframe. An additional LBT may be desirable before the transmission of SRS unless the SRS-configured UEs are scheduled in the same uplink subframe and, thus, the SRS transmission immediately follows the PUSCH transmission.

For some embodiments, SRS may be transmitted in the first symbol of an uplink subframe. UEs configured for SRS transmission only, or for PUSCH transmission only, or for both SRS and PUSCH transmission may all perform LBT synchronously before the start of the UL subframe. UEs configured for PUSCH transmission without SRS transmission may send a reservation signal during a first symbol designated for SRS transmission. The reservation signal may be common to all UEs, and one particular cyclic shift version may be reserved and used for such purpose, so that the eNB may advantageously distinguish a reservation signal from valid SRS transmissions.

In some embodiments, SRS may be frequency-domain multiplexed with sPUCCH. LBT may be performed before the transmission of sPUCCH resources. As with SRS transmitted in the first symbol of an uplink subframe, a common reservation signal may be transmitted before transmission of PUSCH, which may advantageously avoid an additional LBT before transmission of PUSCH.

In self-scheduling cases, UL LBT may employ either a single CCA duration of at least <NUM>, including a defer duration of <NUM> followed by one CCA slot, and a maximum contention window size of <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>.

<FIG> illustrates a scenario of various cases of User Equipment (UE) performed LBT, in accordance with some embodiments of the disclosure. A scenario may comprise a set of subframes <NUM>, which may in turn comprise a set of DL subframes <NUM> (which may be transmitted by an eNB), a set of UL subframes <NUM> (which may be transmitted by one or more UEs), and a transition period <NUM> between DL subframes <NUM> and UL subframes <NUM>. Transition period <NUM> may comprise at least a portion of a DL subframe (which may span a DwPTS), followed by a potential gap for switching between transmission and reception and CCA or a short LBT, followed by an sPUCCH (which may span between one and four SC-FDMA symbols).

A UE may accordingly be disposed to performing LBT under various conditions. In some embodiments, an eNB may explicitly indicate whether a UE may skip LBT before transmission of PUSCH. For some embodiments, LBT may not be needed if a UE has transmitted a reservation signal or sPUCCH (e.g., in transition period <NUM>). In some embodiments, LBT may not be needed if a UE has transmitted in an immediately previous subframe.

Although a UE may be disposed to performing LBT before any transmission in principle, a UE may skip performing LBT in some situations as illustrated in <FIG>. In such cases, an eNB may explicitly indicate whether the UE may skip performing LBT before transmission of PUSCH.

In various situations, one or more UEs configured for sPUCCH transmissions may implicitly infer whether skipping LBT is allowed. If the UEs are also scheduled to transmit PUSCH in a following uplink subframe, the UEs may not need to perform an additional LBT before the transmission of PUSCH if an LBT has successfully finished before transmission of sPUCCH. However, if an LBT requirement for the PUSCH is more strict than an LBT requirement for the sPUCCH transmission, the UEs may perform LBT required for PUSCH transmission before sPUCCH.

For some embodiments, it is possible that a UE may be configured for sPUCCH transmission, but may skip the sPUCCH transmission due to the failure of LBT. Nevertheless, the UE may still attempt the following PUSCH transmission. In this case, a gap may be placed between the sPUCCH and PUSCH transmissions for LBT.

In some embodiments, a gap between sPUCCH and PUSCH may be avoided by transmitting a reservation signal on an interlace of sPUCCH. A common dedicated sPUCCH format (e.g., format <NUM>) or an SRS sequence that is multiplexed with sPUCCH may be pre-allocated as a reservation signal. A fixed Orthogonal Cover Code (OCC) and cyclic shift of a base sequence can be used as reservation signal. The reservation signal is common to all UEs. A reservation can be any useful signal such as transmission of DMRS or SRS.

For some embodiments, a gap (e.g., one symbol) between multiple UL subframes may be skipped if the same UEs may be scheduled over multiple contiguous uplink subframes. A UE may skip an additional LBT after its first PUSCH transmission and may continue to transmit in its second uplink subframe. An eNB may explicitly indicate whether UL LBT may be skipped between UL subframes.

In some embodiments, if multiple users are scheduled for UL transmission, a UL LBT gap may be employed in all UL subframes. This may advantageously increase opportunities for UEs to start transmission in the middle of contiguously scheduled subframes, if a UE failed to complete LBT before the contiguous scheduled subframes.

In some embodiments, if a single user is scheduled in the contiguous uplink subframes, and if no ePUCCH is present from other UEs, a UE may skip LBT in the subsequent subframes without an explicit indication from the eNB.

For some embodiments, an eNB may explicitly indicate whether a UE should perform LBT and/or whether the symbol should to be punctured for an LBT gap for each of the scheduled UL subframes. In some embodiments, a one-bit indication may be transmitted via UL grant or via common PDCCH. A first value (e.g., a "<NUM>") may be used to indicate that a UE needs to perform LBT and/or puncture a symbol for an LBT gap, while a second value (e.g., a "<NUM>") may be used to indicate that the UE does not need to perform LBT and/or symbol puncturing.

In some embodiments, even if the second value is indicated, a UE may override the LBT indication and perform LBT. For example, when a UE has not successfully completed LBT for the transmission of preceding UL subframes, the UE may override an LBT indication from an eNB and may instead perform LBT.

<FIG> illustrates a scenario of various cases of UL LBT, in accordance with some embodiments of the disclosure. A scenario <NUM> may comprise a first case <NUM> and a second case <NUM>. In first case <NUM>, an initial symbol (e.g., a symbol number <NUM>) of a subframe scheduled for a UE for UL transmission (for, e.g., PUSCH transmission) is punctured for LBT. In second case <NUM> not covered by the claims, a last symbol (e.g., a symbol number <NUM>) of a subframe previous to a subframe for a UE for UL transmission (for, e.g., PUSCH transmission) may be punctured for LBT.

Accordingly, for PUSCH transmissions, particular symbols may be predetermined for performing UL LBT. According to the invention, an initial symbol (e.g., symbol number <NUM>) of a current UL subframe is punctured for UL LBT gap. For some embodiments not covered by the claims, a last symbol (e.g., symbol number <NUM>) of a previous subframe may be punctured.

According to the invention, when an initial symbol is punctured and when contiguous subframes are scheduled to the same UE, an eNB provides an indication to only puncture the first subframe of these contiguous subframes for LBT. If an LBT at a first subframe fails, an eNB cannot know a priori whether the following subframes are punctured or not. An eNB may employ blind detection, which may increase complexity. For some embodiments, a UE may indicate the start of a UL subframe via modifying DMRS to depend on a starting position of the PUSCH transmission.

<FIG> illustrates an eNB and a UE, in accordance with some embodiments of the disclosure. <FIG> includes block diagrams of an eNB <NUM> and a UE <NUM> which are operable to co-exist with each other and other elements of an LTE network. High-level, simplified architectures of eNB <NUM> and UE <NUM> are described so as not to obscure the embodiments. It should be noted that in some embodiments, eNB <NUM> may be a stationary non-mobile device.

eNB <NUM> is coupled to one or more antennas <NUM>, and UE <NUM> is similarly coupled to one or more antennas <NUM>. However, in some embodiments, eNB <NUM> may incorporate or comprise antennas <NUM>, and UE <NUM> in various embodiments may incorporate or comprise antennas <NUM>.

In some embodiments, antennas <NUM> and/or antennas <NUM> may comprise one or more directional or omni-directional antennas, including monopole antennas, dipole antennas, loop antennas, patch antennas, microstrip antennas, coplanar wave antennas, or other types of antennas suitable for transmission of RF signals. In some MIMO (multiple-input and multiple output) embodiments, antennas <NUM> are separated to take advantage of spatial diversity.

eNB <NUM> and UE <NUM> are operable to communicate with each other on a network, such as a wireless network. eNB <NUM> and UE <NUM> may be in communication with each other over a wireless communication channel <NUM>, which has both a downlink path from eNB <NUM> to UE <NUM> and an uplink path from UE <NUM> to eNB <NUM>.

As illustrated in <FIG>, in some embodiments, eNB <NUM> may include a physical layer circuitry <NUM>, a MAC (media access control) circuitry <NUM>, a processor <NUM>, a memory <NUM>, and a hardware processing circuitry <NUM>. A person skilled in the art will appreciate that other components not shown may be used in addition to the components shown to form a complete eNB.

In some embodiments, physical layer circuitry <NUM> includes a transceiver <NUM> for providing signals to and from UE <NUM>. Transceiver <NUM> provides signals to and from UEs or other devices using one or more antennas <NUM>. In some embodiments, MAC circuitry <NUM> controls access to the wireless medium. Memory <NUM> may be, or may include, a storage media/medium such as a magnetic storage media (e.g., magnetic tapes or magnetic disks), an optical storage media (e.g., optical discs), an electronic storage media (e.g., conventional hard disk drives, solid-state disk drives, or flash-memory-based storage media), or any tangible storage media or non-transitory storage media. Hardware processing circuitry <NUM> may comprise logic devices or circuitry to perform various operations. In some embodiments, processor <NUM> and memory <NUM> are arranged to perform the operations of hardware processing circuitry <NUM>, such as operations described herein with reference to logic devices and circuitry within eNB <NUM> and/or hardware processing circuitry <NUM>.

Accordingly, in some embodiments, eNB <NUM> may be a device comprising an application processor, a memory, one or more antenna ports, and an interface for allowing the application processor to communicate with another device.

As is also illustrated in <FIG>, in some embodiments, UE <NUM> may include a physical layer circuitry <NUM>, a MAC circuitry <NUM>, a processor <NUM>, a memory <NUM>, a hardware processing circuitry <NUM>, a wireless interface <NUM>, and a display <NUM>. A person skilled in the art would appreciate that other components not shown may be used in addition to the components shown to form a complete UE.

In some embodiments, physical layer circuitry <NUM> includes a transceiver <NUM> for providing signals to and from eNB <NUM> (as well as other eNBs). Transceiver <NUM> provides signals to and from eNBs or other devices using one or more antennas <NUM>. In some embodiments, MAC circuitry <NUM> controls access to the wireless medium. Memory <NUM> may be, or may include, a storage media'medium such as a magnetic storage media (e.g., magnetic tapes or magnetic disks), an optical storage media (e.g., optical discs), an electronic storage media (e.g., conventional hard disk drives, solid-state disk drives, or flash-memory-based storage media), or any tangible storage media or non-transitory storage media. Wireless interface <NUM> may be arranged to allow the processor to communicate with another device. Display <NUM> may provide a visual and/or tactile display for a user to interact with UE <NUM>, such as a touch-screen display. Hardware processing circuitry <NUM> may comprise logic devices or circuitry to perform various operations. In some embodiments, processor <NUM> and memory <NUM> may be arranged to perform the operations of hardware processing circuitry <NUM>, such as operations described herein with reference to logic devices and circuitry within UE <NUM> and/or hardware processing circuitry <NUM>.

Accordingly, in some embodiments, UE <NUM> may be a device comprising an application processor, a memory, one or more antennas, a wireless interface for allowing the application processor to communicate with another device, and a touch-screen display.

Elements of <FIG>, and elements of other figures having the same names or reference numbers, can operate or function in the manner described herein with respect to any such figures (although the operation and function of such elements is not limited to such descriptions). For example, <FIG> also depicts embodiments of eNBs, hardware processing circuitry of eNBs, UEs, and/or hardware processing circuitry of UEs, and the embodiments described with respect to <FIG> and <FIG> can operate or function in the manner described herein with respect to any of the figures.

In addition, although eNB <NUM> and UE <NUM> are each described as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements and/or other hardware elements. In some embodiments of this disclosure, the functional elements can refer to one or more processes operating on one or more processing elements. Examples of software and/or hardware configured elements include Digital Signal Processors (DSPs), one or more microprocessors, DSPs, Field-Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), Radio-Frequency Integrated Circuits (RFICs), and so on.

<FIG> illustrates hardware processing circuitries for an eNB for LBT and starting position indication in contiguous UL subframe transmission, in accordance with some embodiments of the disclosure. With reference to <FIG>, an eNB may include various hardware processing circuitries discussed below (such as hardware processing circuitry <NUM> of <FIG>), which may in turn comprise logic devices and/or circuitry operable to perform various operations. For example, in <FIG>, eNB <NUM> (or various elements or components therein, such as hardware processing circuitry <NUM>, or combinations of elements or components therein) may include part of, or all of, these hardware processing circuitries.

In some embodiments, one or more devices or circuitries within these hardware processing circuitries may be implemented by combinations of software-configured elements and/or other hardware elements. For example, processor <NUM> (and/or one or more other processors which eNB <NUM> may comprise), memory <NUM>, and/or other elements or components of eNB <NUM> (which may include hardware processing circuitry <NUM>) may be arranged to perform the operations of these hardware processing circuitries, such as operations described herein with reference to devices and circuitry within these hardware processing circuitries. In some embodiments, processor <NUM> (and/or one or more other processors which eNB <NUM> may comprise) may be a baseband processor.

Returning to <FIG>, an apparatus of eNB <NUM> (or another eNB or base station), which may be operable to communicate with one or more UEs on a wireless network, may comprise hardware processing circuitry <NUM>. In some embodiments, hardware processing circuitry <NUM> may comprise one or more antenna ports <NUM> operable to provide various transmissions over a wireless communication channel (such as wireless communication channel <NUM>). Antenna ports <NUM> may be coupled to one or more antennas <NUM> (which may be antennas <NUM>). In some embodiments, hardware processing circuitry <NUM> may incorporate antennas <NUM>, while in other embodiments, hardware processing circuitry <NUM> may merely be coupled to antennas <NUM>.

Antenna ports <NUM> and antennas <NUM> may be operable to provide signals from an eNB to a wireless communications channel and/or a UE, and may be operable to provide signals from a UE and/or a wireless communications channel to an eNB. For example, antenna ports <NUM> and antennas <NUM> may be operable to provide transmissions from eNB <NUM> to wireless communication channel <NUM> (and from there to UE <NUM>, or to another UE). Similarly, antennas <NUM> and antenna ports <NUM> may be operable to provide transmissions from a wireless communication channel <NUM> (and beyond that, from UE <NUM>, or another UE) to eNB <NUM>.

Hardware processing circuitry <NUM> may comprise various circuitries operable in accordance with the various embodiments discussed herein. With reference to <FIG>, hardware processing circuitry <NUM> may comprise a first circuitry <NUM>, a second circuitry <NUM>, and/or a third circuitry <NUM>. First circuitry <NUM> may be operable to schedule a plurality of contiguous subframes for the UE for UL transmission. Second circuitry <NUM> may be operable to determine an initial subframe used by the UE for UL transmission.

In some embodiments, second circuitry <NUM> may be operable to determine the initial subframe by blind detection through performing a first hypothesis test and a second hypothesis test. For some embodiments, first hypothesis test may be for a starting position at a first symbol and the second hypothesis test may be for a starting position at a second symbol. In some embodiments, third circuitry <NUM> may be operable to determine the starting position of a received subframe based on a DMRS. Second circuitry <NUM> may provide the received subframe to third circuitry <NUM> via an interface <NUM>.

For some embodiments, the DMRS may indicate a symbol of a starting position of the received subframe. In some embodiments, the DMRS may be transmitted in a first symbol of the subframe. For some embodiments, the DMRS may be modulated with a phase shift to carry a one-bit indicator of a starting symbol of the subframe.

In some embodiments, hardware processing circuitry <NUM> may be coupled to a transceiver circuitry for at least one of: generating transmissions, encoding transmissions, processing transmissions, or decoding transmissions.

In some embodiments, first circuitry <NUM>, second circuitry <NUM>, and/or third circuitry <NUM> may be implemented as separate circuitries. In other embodiments, first circuitry <NUM>, second circuitry <NUM>, and/or third circuitry <NUM> may be combined and implemented together in a circuitry without altering the essence of the embodiments.

<FIG> illustrates hardware processing circuitries for a UE for LBT and starting position indication in contiguous UL subframe transmission, in accordance with some embodiments of the disclosure. <FIG> illustrates hardware processing circuitries for a UE for channel access for transmission of PUSCH and UL control, in accordance with some embodiments of the disclosure. With reference to <FIG>, a UE may include various hardware processing circuitries discussed below (such as hardware processing circuitry <NUM> of <FIG> and hardware processing circuitry <NUM> of <FIG>), which may in turn comprise logic devices and/or circuitry operable to perform various operations. For example, in <FIG>, UE <NUM> (or various elements or components therein, such as hardware processing circuitry <NUM>, or combinations of elements or components therein) may include part of, or all of, these hardware processing circuitries.

In some embodiments, one or more devices or circuitries within these hardware processing circuitries may be implemented by combinations of software-configured elements and/or other hardware elements. For example, processor <NUM> (and/or one or more other processors which UE <NUM> may comprise), memory <NUM>, and/or other elements or components of UE <NUM> (which may include hardware processing circuitry <NUM>) may be arranged to perform the operations of these hardware processing circuitries, such as operations described herein with reference to devices and circuitry within these hardware processing circuitries. In some embodiments, processor <NUM> (and/or one or more other processors which UE <NUM> may comprise) may be a baseband processor.

Returning to <FIG>, an apparatus of UE <NUM> (or another UE or mobile handset), which may be operable to communicate with one or more eNBs on a wireless network, may comprise hardware processing circuitry <NUM>. In some embodiments, hardware processing circuitry <NUM> may comprise one or more antenna ports <NUM> operable to provide various transmissions over a wireless communication channel (such as wireless communication channel <NUM>). Antenna ports <NUM> may be coupled to one or more antennas <NUM> (which may be antennas <NUM>). In some embodiments, hardware processing circuitry <NUM> may incorporate antennas <NUM>, while in other embodiments, hardware processing circuitry <NUM> may merely be coupled to antennas <NUM>.

Antenna ports <NUM> and antennas <NUM> may be operable to provide signals from a UE to a wireless communications channel and/or an eNB, and may be operable to provide signals from an eNB and/or a wireless communications channel to a UE. For example, antenna ports <NUM> and antennas <NUM> may be operable to provide transmissions from UE <NUM> to wireless communication channel <NUM> (and from there to eNB <NUM>, or to another eNB). Similarly, antennas <NUM> and antenna ports <NUM> may be operable to provide transmissions from a wireless communication channel <NUM> (and beyond that, from eNB <NUM>, or another eNB) to UE <NUM>.

Hardware processing circuitry <NUM> may comprise various circuitries operable in accordance with the various embodiments discussed herein. With reference to <FIG>, hardware processing circuitry <NUM> may comprise a first circuitry <NUM>, a second circuitry <NUM>, and/or a third circuitry <NUM>. First circuitry <NUM> may be operable to identify a first subframe being unavailable for a first LBT procedure within the unlicensed spectrum, in which the first LBT procedure determined the unlicensed spectrum to be busy. Second circuitry <NUM> may be operable to perform a second LBT procedure in a second subframe subsequent to the first subframe. Third circuitry <NUM> may be operable to generate an UL transmission over the unlicensed spectrum in the second subframe. Third circuitry may provide information regarding the UL transmission to second circuitry <NUM> via an interface <NUM>.

In some embodiments, the second subframe may be immediately subsequent to the first subframe. For some embodiments, at least one additional subframe separates the first subframe from the second subframe. In some embodiments, the first subframe and the second subframe may be within a contiguous set of subframes scheduled for the UE. For some embodiments, the second LBT procedure may be performed contrary to at least one of: a no-puncturing indication from the eNB, or a no-LBT indication from the eNB. In some embodiments, the second LBT procedure may be performed when an LBT for a previous UL subframe has determined the unlicensed spectrum to be busy.

For some embodiments, the UE may perform the second LBT procedure within an initial symbol following a subframe boundary. In some embodiments, the UE may wait until one symbol before a following subframe boundary to perform the second LBT procedure. For some embodiments, third circuitry <NUM> may be operable to generate, for transmission within a duration between a successful LBT procedure and a following subframe boundary, one of: a reservation signal, a SRS, or a DMRS.

In some embodiments, hardware processing circuitry <NUM> may be coupled to a transceiver circuitry for performing a sensing for an LBT procedure.

In some embodiments, first circuitry <NUM>, second circuitry <NUM>, and/or third circuitry <NUM> may be implemented as separate circuitries. In other embodiments, first circuitry <NUM>, second circuitry <NUM>, and third circuitry <NUM> may be combined and implemented together in a circuitry without altering the essence of the embodiments.

Hardware processing circuitry <NUM> may comprise various circuitries operable in accordance with the various embodiments discussed herein. With reference to <FIG>, hardware processing circuitry <NUM> may comprise a first circuitry <NUM>, a second circuitry <NUM>, a third circuitry <NUM>, and/or a fourth circuitry <NUM>. First circuitry <NUM> may be operable to sense the unlicensed spectrum before a subframe corresponding to a scheduled PUSCH transmission by the UE, the PUSCH transmission spanning an ending portion of a subframe. Second circuitry <NUM> may be operable to perform an LBT procedure to determine whether the unlicensed spectrum is idle. First circuitry <NUM> may be operable to provide an interface to the unlicensed spectrum to second circuitry <NUM> via an interface <NUM>. Third circuitry <NUM> may generate the scheduled PUSCH transmission if the unlicensed spectrum is determined to be idle. Fourth circuitry <NUM> may defer the scheduled PUSCH during the corresponding subframe if the unlicensed spectrum is determined to be busy. Fourth circuitry <NUM> may be operable to provide information regarding the deferral to third circuitry <NUM> via an interface <NUM>.

In some embodiments, third circuitry <NUM> may be operable to generate an sPUCCH for an ending portion of a subframe prior to the subframe scheduled for the PUSCH transmission. For some embodiments, the ending portion may span a number of symbols immediately prior to an end of a subframe, the number of symbols being one of: one symbol, two symbols, three symbols, or four symbols.

For some embodiments, third circuitry <NUM> may be operable to generate, during a duration of a SRS transmission, one of: a reservation signal, a SRS, or a DMRS. In some embodiments, the reservation signal may be common to a plurality of UEs. For some embodiments, the SRS may be frequency-multiplexed with the sPUCCH.

In some embodiments, the LBT procedure may be a single-interval LBT procedure. For some embodiments, the LBT procedure may be a Category <NUM> LBT. In some embodiments, the LBT procedure may perform no LBT based on an indication from the eNB.

For some embodiments, the LBT procedure may be performed in a last symbol of a subframe before the subframe scheduled for PUSCH transmission. In some embodiments, the LBT procedure may be performed in a first symbol of the subframe scheduled for PUSCH transmission. For some embodiments, second circuitry <NUM> may be operable to process an indication from the eNB to do one of: perform the LBT procedure for the scheduled PUSCH, or puncture at least one symbol for an LBT gap for the scheduled PUSCH.

In some embodiments, the indication may be carried within one of: a UL grant, or a PDCCH. For some embodiments, the LBT procedure may be performed without consideration of the indication following a determination that the unlicensed spectrum was busy based upon a previous LBT procedure.

In some embodiments, hardware processing circuitry <NUM> may be coupled to a transceiver circuitry for performing the sensing.

In some embodiments, first circuitry <NUM>, second circuitry <NUM>, third circuitry <NUM>, and/or fourth circuitry <NUM> may be implemented as separate circuitries. In other embodiments, first circuitry <NUM>, second circuitry <NUM>, third circuitry <NUM>, and fourth circuitry <NUM> may be combined and implemented together in a circuitry without altering the essence of the embodiments.

<FIG> illustrates methods for an eNB for LBT and starting position indication in contiguous UL subframe transmission, in accordance with some embodiments of the disclosure. With reference to <FIG>, various methods that may relate to eNB <NUM> and hardware processing circuitry <NUM> are discussed below. Although the actions in method <NUM> of <FIG> are shown in a particular order, the order of the actions can be modified. Thus, the illustrated embodiments can be performed in a different order, and some actions may be performed in parallel. Some of the actions and/or operations listed in <FIG> are optional in accordance with certain embodiments. The numbering of the actions presented is for the sake of clarity and is not intended to prescribe an order of operations in which the various actions must occur. Additionally, operations from the various flows may be utilized in a variety of combinations.

Moreover, in some embodiments, machine readable storage media may have executable instructions that, when executed, cause eNB <NUM> and/or hardware processing circuitry <NUM> to perform an operation comprising the methods of <FIG>. Such machine readable storage media may include any of a variety of storage media, like magnetic storage media (e.g., magnetic tapes or magnetic disks), optical storage media (e.g., optical discs), electronic storage media (e.g., conventional hard disk drives, solid-state disk drives, or flash-memory-based storage media), or any other tangible storage media or non-transitory storage media.

In some embodiments, an apparatus may comprise means for performing various actions and/or operations of the methods of <FIG>.

Returning to <FIG>, various methods may be in accordance with the various embodiments discussed herein. A method <NUM> may comprise a scheduling <NUM> and/or a determining <NUM>. Method <NUM> may also comprise a determining <NUM> and/or a determining <NUM>. In scheduling <NUM>, a plurality of contiguous subframes may be scheduled for a UE for UL transmission. In determining <NUM>, an initial subframe used by the UE for UL transmission may be determined.

In determining <NUM>, the initial subframe may be determined by blind detection through performing a first hypothesis test and a second hypothesis test. In some embodiments, the first hypothesis test may be for a starting position at a first symbol and the second hypothesis test may be for a starting position at a second symbol. In determining <NUM>, the starting position of a received subframe may be determined based on a DMRS.

<FIG> illustrates methods for a UE for LBT and starting position indication in contiguous UL subframe transmission, in accordance with some embodiments of the disclosure. <FIG> illustrates methods for a UE for channel access for transmission of PUSCH and UL control, in accordance with some embodiments of the disclosure. With reference to <FIG>, methods that may relate to UE <NUM> and hardware processing circuitry <NUM> are discussed below. Although the actions in the methods <NUM> and <NUM> of <FIG> and <FIG> are shown in a particular order, the order of the actions can be modified. Thus, the illustrated embodiments can be performed in a different order, and some actions may be performed in parallel. Some of the actions and/or operations listed in <FIG> are optional in accordance with certain embodiments. The numbering of the actions presented is for the sake of clarity and is not intended to prescribe an order of operations in which the various actions must occur. Additionally, operations from the various flows may be utilized in a variety of combinations.

Moreover, in some embodiments, machine readable storage media may have executable instructions that, when executed, cause UE <NUM> and/or hardware processing circuitry <NUM> to perform an operation comprising the methods of <FIG> and <FIG>. Such machine readable storage media may include any of a variety of storage media, like magnetic storage media (e.g., magnetic tapes or magnetic disks), optical storage media (e.g., optical discs), electronic storage media (e.g., conventional hard disk drives, solid-state disk drives, or flash-memory-based storage media), or any other tangible storage media or non-transitory storage media.

Returning to <FIG>, various methods may be in accordance with the various embodiments discussed herein. A method <NUM> may comprise an identifying <NUM>, a performing <NUM>, and/or a generating <NUM>. Method <NUM> may also comprise a generating <NUM>. In identifying <NUM>, a first subframe may be identified as being unavailable for a first Listen-Before-Talk (LBT) procedure within the unlicensed spectrum, in which the first LBT procedure determined the unlicensed spectrum to be busy. In performing <NUM>, a second LBT procedure may be performed in a second subframe subsequent to the first subframe. In generating <NUM>, a UL transmission may be generated over the unlicensed spectrum in the second subframe.

In some embodiments, the second subframe may be immediately subsequent to the first subframe. For some embodiments, at least one additional subframe may separate the first subframe from the second subframe. In some embodiments, the first subframe and the second subframe may be within a contiguous set of subframes scheduled for the UE.

For some embodiments, the second LBT procedure may be performed contrary to at least one of: a no-puncturing indication from an eNB, or a no-LBT indication from the eNB. In some embodiments, the second LBT procedure may be performed when an LBT for a previous UL subframe has determined the unlicensed spectrum to be busy. For some embodiments, the UE may perform the second LBT procedure within an initial symbol following a subframe boundary.

In some embodiments, the UE may wait until one symbol before a following subframe boundary to perform the second LBT procedure. For some embodiments, in generating <NUM>, one of a reservation signal, a SRS, or a DMRS may be generated for transmission within a duration between a successful LBT procedure and a following subframe boundary.

Returning to <FIG>, various methods may be in accordance with the various embodiments discussed herein. A method <NUM> may comprise a sensing <NUM>, a performing <NUM>, a generating <NUM>, and/or a deferring <NUM>. Method <NUM> may also comprise a generating <NUM>, a generating <NUM>, and/or a processing <NUM>.

In sensing <NUM>, the unlicensed spectrum may be sensed before a subframe corresponding to a scheduled PUSCH transmission by the UE, the PUSCH transmission spanning an ending portion of a subframe. In performing <NUM>, an LBT procedure may be performed to determine whether the unlicensed spectrum is idle. In generating <NUM>, the scheduled PUSCH transmission may be generated if the unlicensed spectrum is determined to be idle. In deferring <NUM>, the scheduled PUSCH may be deferred during the corresponding subframe if the unlicensed spectrum is determined to be busy.

In generating <NUM>, an sPUCCH may be generated for an ending portion of a subframe prior to the subframe scheduled for the PUSCH transmission. In some embodiments, the ending portion may span a number of symbols immediately prior to an end of a subframe, the number of symbols being one of: one symbol, two symbols, three symbols, or four symbols.

In generating <NUM>, during a duration of a SRS transmission, one of a reservation signal, a SRS, or a DMRS may be generated. In some embodiments, the reservation signal may be common to a plurality of UEs. For some embodiments, the SRS may be frequency-multiplexed with the sPUCCH. In some embodiments, the LBT procedure may be a single-interval LBT procedure. For some embodiments, the LBT procedure may be a Category <NUM> LBT. In some embodiments, the LBT procedure may perform no LBT based on an indication from the eNB. For some embodiments, the LBT procedure may be performed in a last symbol of a subframe before the subframe scheduled for PUSCH transmission. In some embodiments, the LBT procedure may be performed in a first symbol of the subframe scheduled for PUSCH transmission.

In processing <NUM>, an indication from an eNB to do one of performing the LBT procedure for the scheduled PUSCH, or puncturing at least one symbol for an LBT gap for the scheduled PUSCH may be processed. In some embodiments, the indication may be carried within one of: a UL grant, or a PDCCH. For some embodiments, the LBT procedure may be performed without consideration of the indication following a determination that the unlicensed spectrum was busy based upon a previous LBT procedure.

<FIG> illustrates example components of a UE device, in accordance with some embodiments of the disclosure. In some embodiments, a UE device <NUM> may include application circuitry <NUM>, baseband circuitry <NUM>, Radio Frequency (RF) circuitry <NUM>, front-end module (FEM) circuitry <NUM>, a low-power wake-up receiver (LP-WUR), and one or more antennas <NUM>, coupled together at least as shown. In some embodiments, the UE device <NUM> may include additional elements such as, for example, memory/storage, display, camera, sensor, and/or input/output (I/O) interface.

The baseband circuitry <NUM> may include one or more baseband processors and/or control logic to process baseband signals received from a receive signal path of the RF circuitry <NUM> and to generate baseband signals for a transmit signal path of the RF circuitry <NUM>. Baseband processing circuity <NUM> may interface with the application circuitry <NUM> for generation and processing of the baseband signals and for controlling operations of the RF circuitry <NUM>. For example, in some embodiments, the baseband circuitry <NUM> may include a second generation (<NUM>) baseband processor 1404A, third generation (<NUM>) baseband processor 1404B, fourth generation (<NUM>) baseband processor 1404C, and/or other baseband processor(s) 1404D for other existing generations, generations in development or to be developed in the future (e.g., fifth generation (<NUM>), <NUM>, etc.). The baseband circuitry <NUM> (e.g., one or more of baseband processors 1404A-D) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry <NUM>. The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry <NUM> may include Fast-Fourier Transform (FFT), precoding, and/or constellation mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry <NUM> may include convolution, tail-biting convolution, turbo, Viterbi, and/or Low Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

In some embodiments, the baseband circuitry <NUM> may include elements of a protocol stack such as, for example, elements of an EUTRAN protocol including, for example, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and/or RRC elements. A central processing unit (CPU) 1404E of the baseband circuitry <NUM> may be configured to run elements of the protocol stack for signaling of the PHY, MAC, RLC, PDCP and/or RRC layers. In some embodiments, the baseband circuitry may include one or more audio digital signal processor(s) (DSP) 1404F. The audio DSP(s) 1404F may be include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry <NUM> and the application circuitry <NUM> may be implemented together such as, for example, on a system on a chip (SOC).

In some embodiments, the RF circuitry <NUM> may include a receive signal path and a transmit signal path. The receive signal path of the RF circuitry <NUM> may include mixer circuitry 1406A, amplifier circuitry 1406B and filter circuitry 1406C. The transmit signal path of the RF circuitry <NUM> may include filter circuitry 1406C and mixer circuitry 1406A. RF circuitry <NUM> may also include synthesizer circuitry 1406D for synthesizing a frequency for use by the mixer circuitry 1406A of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 1406A of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry <NUM> based on the synthesized frequency provided by synthesizer circuitry 1406D. The amplifier circuitry 1406B may be configured to amplify the down-converted signals and the filter circuitry 1406C may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry <NUM> for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry 1406A of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 1406A of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 1406D to generate RF output signals for the FEM circuitry <NUM>. The baseband signals may be provided by the baseband circuitry <NUM> and may be filtered by filter circuitry 1406C. The filter circuitry 1406C may include a low-pass filter (LPF), although the scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 1406A of the receive signal path and the mixer circuitry 1406A of the transmit signal path may include two or more mixers and may be arranged for quadrature down-conversion and/or up-conversion respectively. In some embodiments, the mixer circuitry 1406A of the receive signal path and the mixer circuitry 1406A of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 1406A of the receive signal path and the mixer circuitry 1406A may be arranged for direct down-conversion and/or direct up-conversion, respectively. In some embodiments, the mixer circuitry 1406A of the receive signal path and the mixer circuitry 1406A of the transmit signal path may be configured for super-heterodyne operation.

In some embodiments, the synthesizer circuitry 1406D may be a fractional-N synthesizer or a fractional N/N+<NUM> synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 1406D may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

The synthesizer circuitry 1406D may be configured to synthesize an output frequency for use by the mixer circuitry 1406A of the RF circuitry <NUM> based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 1406D may be a fractional N/N+<NUM> synthesizer.

Synthesizer circuitry 1406D of the RF circuitry <NUM> may include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by either N or N+<NUM> (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuitry 1406D may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fLO). In some embodiments, the RF circuitry <NUM> may include an IQ/polar converter.

In some embodiments, the UE <NUM> comprises a plurality of power saving mechanisms. If the UE <NUM> is in an RRC_Connected state, where it is still connected to the eNB as it expects to receive traffic shortly, then it may enter a state known as Discontinuous Reception Mode (DRX) after a period of inactivity. During this state, the device may power down for brief intervals of time and thus save power.

If there is no data traffic activity for an extended period of time, then the UE <NUM> may transition off to an RRC_Idle state, where it disconnects from the network and does not perform operations such as channel quality feedback, handover, etc. The UE <NUM> goes into a very low power state and it performs paging where again it periodically wakes up to listen to the network and then powers down again. Since the device might not receive data in this state, in order to receive data, it should transition back to RRC_Connected state.

In addition, in various embodiments, an eNB device may include components substantially similar to one or more of the example components of UE device <NUM> described herein.

It is pointed out that elements of any of the Figures herein having the same reference numbers and/or names as elements of any other Figure herein may, in various embodiments, operate or function in a manner similar those elements of the other Figure (without being limited to operating or functioning in such a manner).

While the disclosure has been described in conjunction with specific embodiments thereof, many alternatives, modifications and variations of such embodiments will be apparent to those of ordinary skill in the art in light of the foregoing description. For example, other memory architectures e.g., Dynamic RAM (DRAM) may use the embodiments.

Claim 1:
An apparatus of an Evolved Node-B, eNB, (<NUM>) operable to communicate with a User Equipment, UE, (<NUM>) over an unlicensed spectrum on a wireless network, comprising:
a memory; and
one or more processors to:
schedule a plurality of contiguous subframes for the UE (<NUM>) for Uplink, UL, transmission, and
determine a first subframe to be used by the UE (<NUM>) for UL transmission,
characterized in that
the eNB (<NUM>) indicates to only puncture the first symbol of the first subframe of the plurality of contiguous subframes for carrying out a Listen-Before-Talk, LBT, procedure during the punctured first symbol.