WO2017172829A1

WO2017172829A1 - Listen-before-talk for uplink transmission

Info

Publication number: WO2017172829A1
Application number: PCT/US2017/024621
Authority: WO
Inventors: Qiaoyang Ye; Jeongho Jeon; Seunghee Han; Huaning Niu; Abhijeet Bhorkar
Original assignee: Intel IP Corporation
Priority date: 2016-03-28
Filing date: 2017-03-28
Publication date: 2017-10-05
Also published as: CN109076603B; CN109076603A

Abstract

Described is an apparatus of an Evolved Node-B (eNB) operable to communicate with a User Equipment (UE) on a wireless network. The apparatus may comprise a first circuitry and a second circuitry. The first circuitry may be operable to initiate a single- interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe after a first time period and before a second time period, the single interval LBT procedure having a first duration. The second circuitry may be operable to allocate a second duration within the OFDM symbol for a reservation signal. The second duration may span a symbol time of the OFDM symbol minus the first time period, the first duration, and the second time period.

Description

LISTEN-BEFORE-TALK FOR UPLINK TRANSMISSION CLAIM OF PRIORITY

[0001] The present application claims priority under 35 U.S.C. § 119(e) to United

States Provisional Patent Application Serial Number 62/314,211 filed March 28, 2016 and entitled "Single Interval LBT Related Design For Uplink Transmission In MulteFire/eLAA Systems," which is herein incorporated by reference in its entirety.

BACKGROUND

[0002] Various wireless cellular communication systems have been implemented, including a 3rd Generation Partnership Project (3 GPP) 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 (5G) wireless system / 5G mobile networks system. Next-generation wireless cellular communication systems may provide support for higher bandwidths in part by using unlicensed spectrum

BRIEF DESCRIPTION OF THE DRAWINGS

[0003] 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.

[0004] Fig. 1 illustrates a scenario of an Evolved Node B (eNB) and a plurality of

User Equipments (UEs), in accordance with some embodiments of the disclosure.

[0005] Fig. 2 illustrates a scenario of Listen-Before-Talk (LBT) between a Downlink

(DL) subframe and an Uplink (UL) subframe, in accordance with some embodiments of the disclosure.

[0006] Fig. 3 illustrates a scenario of LBT between a UL subframe and a UL subframe, in accordance with some embodiments of the disclosure.

[0007] Fig. 4 illustrates a scenario of LBT between a DL subframe and a UL subframe, in accordance with some embodiments of the disclosure.

[0008] Fig. 5 illustrates a scenario of LBT between a UL subframe and a UL subframe, in accordance with some embodiments of the disclosure. [0009] Fig. 6 illustrates an eNB and a UE, in accordance with some embodiments of the disclosure.

[0010] Fig. 7 illustrates hardware processing circuitries for a UE for LBT for UL transmissions, in accordance with some embodiments of the disclosure.

[0011] Fig. 8 illustrates methods for a UE for LBT for UL transmissions, in accordance with some embodiments of the disclosure.

[0012] Fig. 9 illustrates methods for a UE for LBT for UL transmissions, in accordance with some embodiments of the disclosure.

[0013] Fig. 10 illustrates example components of a UE device, in accordance with some embodiments of the disclosure.

DETAILED DESCRIPTION

[0014] Various wireless cellular communication systems have been implemented or are being proposed, including a 3rd Generation Partnership Project (3GPP) Universal Mobile Telecommunications System (UMTS), a 3GPP Long-Term Evolution (LTE) system, a 3GPP LTE-Advanced (LTE- A) system, and a 5th Generation wireless / 5th Generation mobile networks (5G) system. The rapid growth of wireless traffic has led to a desire for data rate improvement. On one hand, with mature physical layer techniques, further improvement in spectral efficiency may be marginal. On the other hand, a scarcity of licensed spectrum in low frequency bands may hinder efforts to increase data rates by increasing use of licensed spectrum. Thus, there is an emerging interest in operation of LTE systems in unlicensed spectrum.

[0015] One enhancement for LTE in 3 GPP Release 13 (frozen, end date 2016-03-11

(SP-71)) has been to enable its operation in unlicensed spectrum via Licensed-Assisted Access (LAA), which may expand system bandwidths by utilizing a flexible Carrier Aggregation (CA) framework introduced for LTE-A systems. In some embodiments, for LAA operation or enhanced LAA (eLAA) operation, a primary cell (Pcell) may provide connectivity to a UE in licensed spectrum, whereas a secondary cell (Scell) may provide connectivity in unlicensed spectrum. In some embodiments, a Pcell and an Scell may be collocated, while in some other embodiment, a Pcell and an Scell might not be collocated.

[0016] Enhanced operation of LTE systems in unlicensed spectrum may be supported in future releases and 5G systems. LTE operation in unlicensed spectrum may include LTE operation in unlicensed spectrum via Dual Connectivity (DC), and/or standalone LTE operation systems in unlicensed spectrum. [0017] LTE-based technology may operate solely in unlicensed spectrum without relying upon an "anchor" in the licensed spectrum, such as in MulteFire™ technology by MulteFire Alliance of Fremont California, USA. Such operation may rely on 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. In MulteFire™, a Pcell may operate in or unlicensed spectrum. Standalone LTE operation in unlicensed spectrum may also combine performance benefits of LTE technology with a relative simplicity of Wi-Fi®-like deployments. (Wi-Fi® is a registered trademark of the Wi-Fi Alliance of Austin, Texas, USA.) Standalone LTE operation may accordingly be an advantageous technology in meeting demands of ever- increasing wireless traffic.

[0018] An unlicensed frequency band of current interest is the 5 GHz band, which has wide spectrum with global common availability. The 5 GHz 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 5 GHz band are Wireless Local Area Networks (WLAN) systems, specifically those based on Institute of Electrical and Electronics Engineers (IEEE) 802.11 a/n/ac technologies, which may be used for Wi-Fi® networks.

[0019] 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) procedures may be implemented in LTE LAA systems and/or MulteFire™ 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.

[0020] In some embodiments for standalone LTE operation (which may include

MulteFire™ systems), an Uplink (UL) transmission within a Transmission Opportunity (TxOP) may be subject to a single-interval LBT, which may have a sensing duration of at least 25 microseconds (μβ). For some embodiments, UL transmissions from User

Equipments (UEs) in an eLAA system may follow a Downlink (DL) burst within a Maximum Channel Occupancy Time (MCOT) acquired by an Enhanced Node-B (eNB). Each UE may perform a single 25 LBT procedure before the start of its transmission.

[0021] At least one symbol (e.g., an Orthogonal Frequency-Division Multiplexing

(OFDM) symbol) may be punctured for a UE to perform a single-interval LBT. In some embodiments, a first symbol of a UL subframe (e.g., a symbol 0) may be punctured, and the punctured symbol may be used to perform a single-interval LBT procedure for the current uplink subframe. In some embodiments, a last symbol of a UL subframe (e.g., a symbol 13) may be punctured, and the punctured symbol may be used to perform a single-interval LBT procedure for the following UL subframe.

[0022] A symbol duration of the first symbol and a symbol duration of remaining symbols within a slot in LTE systems may be 71.87 and 71.37 μβ, respectively.

Meanwhile, a single-interval LBT duration may be 25 μβ. If a single-interval LBT is performed right before a UL transmission, there may exist a gap between the end of the transmission in the preceding subframe and the start of the single-interval LBT, with a duration of up to 71.87 μβ - 25 μβ = 46.87 μβ. During this duration, a channel may be sensed as idle and may be grabbed by other transmitters (e.g., Wi-Fi® Access Points (APs) and/or Stations (STAs)). In this case, eLAA systems (e.g., MulteFire™ systems) may lose a chance for transmission.

[0023] As a result, LAA UL operation may experience severe performance degradation. Accordingly, in order to increase UL transmission opportunities in eLAA systems and thus improve UL system performance, a careful design regarding punctured symbol duration may be advantageous.

[0024] Discussed herein are mechanisms and methods for increasing transmission opportunities in eLAA and/or MulteFire™ systems by engaging in potential transmissions within a punctured symbol duration. A gap without transmission within a punctured symbol duration may be reduced, such as by extending a transmission in a previous subframe, or a transmission in a following subframe.

[0025] 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.

[0026] Note that in the corresponding drawings of the embodiments, signals are represented with lines. Some lines may be thicker, to indicate a greater number of constituent signal paths, and/or have arrows at one or more ends, to indicate a direction of information flow. Such indications are not intended to be limiting. Rather, the lines are used in connection with one or more exemplary embodiments to facilitate easier understanding of a circuit or a logical unit. Any represented signal, as dictated by design needs or preferences, may actually comprise one or more signals that may travel in either direction and may be implemented with any suitable type of signal scheme.

[0027] 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."

[0028] The terms "substantially," "close," "approximately," "near," and "about" generally refer to being within +/- 10% 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.

[0029] 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.

[0030] The terms "left," "right," "front," "back," "top," "bottom," "over," "under," and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions.

[0031] 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.

[0032] For the purposes of the present disclosure, the phrases "A and/or B" and "A or

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

[0033] In addition, the various elements of combinatorial logic and sequential logic discussed in the present disclosure may pertain both to physical structures (such as AND gates, OR gates, or XOR gates), or to synthesized or otherwise optimized collections of devices implementing the logical structures that are Boolean equivalents of the logic under discussion.

[0034] In addition, for purposes of the present disclosure, the term "eNB" may refer to a legacy eNB, a next-generation or 5G eNB, an mmWave eNB, an mmWave small cell, an AP, and/or another base station for a wireless communication system. For purposes of the present disclosure, the term "UE" may refer to a UE, a 5G UE, an mmWave UE, an STA, and/or another mobile equipment for a wireless communication system.

[0035] 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.

[0036] 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.

[0037] In various embodiments, resources may span various Resource Blocks (RBs),

Physical Resource Blocks (PRBs), and/or time periods (e.g., frames, subframes, and/or slots) of a wireless communication system. In some contexts, allocated resources (e.g., channels, OFDM, subcarrier frequencies, resource elements (REs), and/or portions thereof) may be formatted for (and prior to) transmission over a wireless communication link. In other contexts, allocated resources (e.g., channels, OFDM symbols, subcarrier frequencies, REs, and/or portions thereof) may be detected from (and subsequent to) reception over a wireless communication link.

[0038] Fig. 1 illustrates a scenario of an eNB and a plurality of UEs, in accordance with some embodiments of the disclosure. A wireless cellular communications scenario 100 may comprise a first eNB 1 10, a second eNB 120, and a UE 130. First eNB 110 may be operable to provide wireless cellular communications services over a geographic area within a first cell 1 1 1, and second eNB 120 may be operable to provide wireless cellular communications services over a geographic area within a second cell 121.

[0039] In some embodiments, first eNB 110 may support DL and/or UL

transmissions with UE 130 over licensed spectrum. For example, first eNB 1 10 may support legacy LTE DL transmissions to UE 130 and/or legacy LTE UL transmissions from UE 130. For some embodiments, second eNB 120 may support DL and/or UL transmissions with UE 130 over unlicensed spectrum. For example, second eNB 120 may support LAA-compliant DL transmissions to UE 130 and/or eLAA-compliant UL transmissions from UE 130.

[0040] eLAA-compliant UL transmissions may be structured in accordance with the

LBT procedures discussed herein. A gap without any transmission within a punctured symbol (e.g., a first OFDM symbol of a subframe) may thereby be advantageously shortened, which may reduce a probability that a corresponding wireless communications channel is used by other, competing systems within the punctured-symbol duration.

[0041] In some embodiments, a single-interval LBT procedure may be performed in a punctured symbol of a UL subframe (e.g., a UL subframe over unlicensed spectrum), and one or more signals (e.g., a reservation signal) may be transmitted after the LBT and before the remainder of the UL subframe, if the LBT is successful.

[0042] For some embodiments, one or more signals (e.g., a reservation signal) may be transmitted in a punctured symbol of a UL subframe (e.g., a UL subframe over unlicensed spectrum), and a single-interval LBT procedure may be transmitted after the one or more signals and before the remainder of the UL subframe, if the LBT is successful.

[0043] Fig. 2 illustrates a scenario of Listen-Bef ore-Talk (LBT) between a Downlink

(DL) subframe and an Uplink (UL) subframe, in accordance with some embodiments of the disclosure. A scenario 200 may comprise a first subframe 210 and a second subframe 220. An OFDM symbol 221 of second subframe 220 (which may be a first symbol or an initial symbol of second subframe 220) may comprise a first time period 231, a second time period 232, a first duration 241, and a second duration 242. First subframe 210 may be a DL subframe, and second subframe 220 may be a UL subframe within the same TxOP as first subframe 210. Scenario 200 may accordingly be a scenario in which a UL subframe follows a DL subframe. In scenario 200, transmission of a reservation signal (e.g., within second duration 242) may follow a single-interval LBT procedure (e.g., within first duration 241).

[0044] Following an end of transmission in first subframe 210, OFDM symbol 221 may comprise first time period 231, which may be a time T_Chi accommodating a maximal delay spread from an eNB to a UE. Following first time period 231, OFDM symbol 221 may comprise first duration 241, which may be a sensing interval or a channel sensing duration TLBT accommodating a single-interval LBT procedure (and which may exclude a receiver-to- transmitter switching time)). Following first duration 241 (e.g., if the single-interval LBT procedure senses the channel to be idle), OFDM symbol 221 may comprise second time period 232, which may be a receiver-to-transmitter switching time

accommodating a UE's switch from receiving to transmitting. In some embodiments, first time period 231, first duration 241, and second time period 232 may span less than 25 μβ. Following second time period 232, OFDM symbol 221 may comprise second duration 242, which may be a time Y accommodating transmission of a signal (e.g., a reservation signal).

[0045] A scheduled UE may thus start transmitting a signal in OFDM symbol 221 at a time Y before the subsequent OFDM symbol. For a symbol duration T_Sym, Y may satisfy the following equation:

[0046] In some embodiments, the transmitted signal may be an extended Cyclic

Prefix (CP). A total CP length of OFDM symbol 221 TCP2 may be: TCP2 = Y + TCPI

where TCPI may denote a legacy LTE CP length.

[0047] For some embodiments, the transmitted signal may be any reservation signal.

Transmission of the reservation signal may be transparent to an eNB and/or may otherwise not involve an eNB.

[0048] Fig. 3 illustrates a scenario of LBT between a UL subframe and a UL subframe, in accordance with some embodiments of the disclosure. A scenario 300 may comprise a first subframe 310 and a second subframe 320. An OFDM symbol 321 of second subframe 320 (which may be a first symbol or an initial symbol of second subframe 320) may comprise a first time period 331, a second time period 332, a first duration 341, and a second duration 342. First subframe 310 may be a UL subframe, and second subframe 320 may be a UL subframe within the same TxOP as first subframe 310. Scenario 300 may accordingly be a scenario in which a UL subframe follows another UL subframe. In scenario 300, transmission of a reservation signal (e.g., within second duration 342) may follow a single- interval LBT procedure (e.g., within first duration 341).

[0049] Following an end of transmission in first subframe 310, OFDM symbol 321 may comprise first time period 331, which may be a maximum of: a time T_Ch2

accommodating a maximal delay spread from a UE to a UE; and a transmitter-to-receiver switching time TT_X→RX accommodating a UE's switch from transmitting to receiving.

Following first time period 331, OFDM symbol 321 may comprise first duration 341, which may be a sensing interval or a channel sensing duration TLBT accommodating a single-interval LBT procedure (and which may exclude a receiver-to-transmitter switching time)).

Following first duration 341 (e.g., if the single-interval LBT procedure senses the channel to be idle), OFDM symbol 321 may comprise second time period 332, which may be a receiver- to-transmitter switching time

accommodating a UE's switch from receiving to transmitting. In some embodiments, first time period 331, first duration 341, and second time period 332 may span less than 25 μβ. Following second time period 332, OFDM symbol 321 may comprise second duration 342, which may be a time Y accommodating transmission of a signal (e.g., a reservation signal).

[0050] A scheduled UE may thus start transmitting a signal in OFDM symbol 321 at a time Y before the subsequent OFDM symbol. For a symbol duration T_Sym, Y may satisfy the following equation:

Y = Tsym - (Max{Tch2,TTx→Rx} + TLBT +

[0051] In some embodiments, the transmitted signal may be an extended Cyclic

Prefix (CP). A total CP length of OFDM symbol 221 TCP2 may be:

TCP2 = Y + TCPI

where TCPI may denote a legacy LTE CP length.

[0052] For some embodiments, the transmitted signal may be any reservation signal.

[0053] Fig. 4 illustrates a scenario of LBT between a DL subframe and a UL subframe, in accordance with some embodiments of the disclosure. A scenario 400 may comprise a first subframe 410 and a second subframe 420. An OFDM symbol 421 of second subframe 420 (which may be a first symbol or an initial symbol of second subframe 420) may comprise a first time period 431, a second time period 432, a first duration 441, and a second duration 442. First subframe 410 may be a DL subframe, and second subframe 420 may be a UL subframe within the same TxOP as first subframe 410. Scenario 400 may accordingly be a scenario in which a UL subframe follows a DL subframe. In scenario 400, a single-interval LBT procedure (e.g., within first duration 441) may follow transmission of a reservation signal (e.g., within second duration 442).

[0054] Following an end of transmission in first subframe 410, OFDM symbol 421 may comprise second duration 442, which may be a time Z accommodating transmission of a signal (e.g., a reservation signal). Following second duration 442, OFDM symbol 421 may comprise first time period 431, which may be a time T_Chi accommodating a maximal delay spread from an eNB to a UE. Following first time period 431, OFDM symbol 421 may comprise first duration 441, which may be a sensing interval or a channel sensing duration TLBT accommodating a single-interval LBT procedure (and which may exclude a receiver-to- transmitter switching time)). Following first duration 441 (e.g., if the single-interval LBT procedure senses the channel to be idle), OFDM symbol 421 may comprise second time period 432, which may be a receiver-to-transmitter switching time

accommodating a UE's switch from receiving to transmitting. In some embodiments, first time period 431, first duration 441, and second time period 432 may span less than 25 μβ.

[0055] An eNB may thus continue to transmit a signal in OFDM symbol 421 for a time Z after first subframe 410. For a symbol duration Tsym, Z may satisfy the following equation:

[0056] For some embodiments, the transmitted signal may be any reservation signal.

Transmission of the reservation signal may be transparent to a UE and/or may otherwise not involve a UE.

[0057] Fig. 5 illustrates a scenario of LBT between a UL subframe and a UL subframe, in accordance with some embodiments of the disclosure. A scenario 500 may comprise a first subframe 510 and a second subframe 520. An OFDM symbol 521 of second subframe 520 (which may be a first symbol or an initial symbol of second subframe 520) may comprise a first time period 531, a second time period 532, a first duration 541, and a second duration 542. First subframe 510 may be a UL subframe, and second subframe 520 may be a UL subframe within the same TxOP as first subframe 510. Scenario 500 may accordingly be a scenario in which a UL subframe follows another UL subframe. In scenario 500, a single- interval LBT procedure (e.g., within first duration 541) may follow transmission of a reservation signal (e.g., within second duration 542).

[0058] Following an end of transmission in first subframe 510, OFDM symbol 521 may comprise second duration 542, which may be a time Z accommodating transmission of a signal (e.g., a reservation signal). Following second duration 542, OFDM symbol 521 may comprise first time period 531, which may be a maximum of: a time T_Ch2 accommodating a maximal delay spread from a UE to a UE; and a transmitter-to-receiver switching time

TTX→RX for a UE to switch from transmitting to receiving. Following first time period 531, OFDM symbol 521 may comprise first duration 541, which may be a sensing interval or a channel sensing duration TLBT accommodating a single-interval LBT procedure (and which may exclude a receiver-to-transmitter switching time)). Following first duration 541 (e.g., if the single-interval LBT procedure senses the channel to be idle), OFDM symbol 521 may comprise second time period 532, which may be a receiver-to-transmitter switching time accommodating a for the UE to switch from receiving to transmitting. In some embodiments, first time period 531, first duration 541, and second time period 532 may span

[0059] A scheduled UE may thus continue to transmit a signal in OFDM symbol 521 for a time Z after first subframe 510. For a symbol duration Tsym, Z may satisfy the following equation:

Z = Tsym - (Max{Tch2,TTx→Rx} + TLBT +

[0060] For some embodiments, the transmitted signal may be any reservation signal.

Transmission of the reservation signal may be transparent to an eNB and/or may otherwise not involve an eNB. [0061] Although Figs. 2 through 5 depict initial symbols or first symbols of a UL subframe as being punctured for LBT, in various embodiments, a last symbol of a UL subframe may be punctured for LBT instead. Such embodiments may have first time periods, second time periods, first durations, and/or second durations substantially similar to those described above positioned within the last symbol of the UL subframe.

[0062] In various embodiments, durations of reservation signals (e.g., a time Y and/or a time Z as discussed here) may be predefined constants. For various embodiments, durations of reservation signals may be semi-statically configured (e.g., via Radio Resource Control (RRC) signaling).

[0063] Fig. 6 illustrates an eNB and a UE, in accordance with some embodiments of the disclosure. Fig. 6 includes block diagrams of an eNB 610 and a UE 630 which are operable to co-exist with each other and other elements of an LTE network. High-level, simplified architectures of eNB 610 and UE 630 are described so as not to obscure the embodiments. It should be noted that in some embodiments, eNB 610 may be a stationary non-mobile device.

[0064] eNB 610 is coupled to one or more antennas 605, and UE 630 is similarly coupled to one or more antennas 625. However, in some embodiments, eNB 610 may incorporate or comprise antennas 605, and UE 630 in various embodiments may incorporate or comprise antennas 625.

[0065] In some embodiments, antennas 605 and/or antennas 625 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 605 are separated to take advantage of spatial diversity.

[0066] eNB 610 and UE 630 are operable to communicate with each other on a network, such as a wireless network. eNB 610 and UE 630 may be in communication with each other over a wireless communication channel 650, which has both a downlink path from eNB 610 to UE 630 and an uplink path from UE 630 to eNB 610.

[0067] As illustrated in Fig. 6, in some embodiments, eNB 610 may include a physical layer circuitry 612, a MAC (media access control) circuitry 614, a processor 616, a memory 618, and a hardware processing circuitry 620. 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. [0068] In some embodiments, physical layer circuitry 612 includes a transceiver 613 for providing signals to and from UE 630. Transceiver 613 provides signals to and from UEs or other devices using one or more antennas 605. In some embodiments, MAC circuitry 614 controls access to the wireless medium. Memory 618 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 620 may comprise logic devices or circuitry to perform various operations. In some embodiments, processor 616 and memory 618 are arranged to perform the operations of hardware processing circuitry 620, such as operations described herein with reference to logic devices and circuitry within eNB 610 and/or hardware processing circuitry 620.

[0069] Accordingly, in some embodiments, eNB 610 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.

[0070] As is also illustrated in Fig. 6, in some embodiments, UE 630 may include a physical layer circuitry 632, a MAC circuitry 634, a processor 636, a memory 638, a hardware processing circuitry 640, a wireless interface 642, and a display 644. 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.

[0071] In some embodiments, physical layer circuitry 632 includes a transceiver 633 for providing signals to and from eNB 610 (as well as other eNBs). Transceiver 633 provides signals to and from eNBs or other devices using one or more antennas 625. In some embodiments, MAC circuitry 634 controls access to the wireless medium. Memory 638 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 642 may be arranged to allow the processor to communicate with another device. Display 644 may provide a visual and/or tactile display for a user to interact with UE 630, such as a touch-screen display. Hardware processing circuitry 640 may comprise logic devices or circuitry to perform various operations. In some embodiments, processor 636 and memory 638 may be arranged to perform the operations of hardware processing circuitry 640, such as operations described herein with reference to logic devices and circuitry within UE 630 and/or hardware processing circuitry 640.

[0072] Accordingly, in some embodiments, UE 630 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.

[0073] Elements of Fig. 6, 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, Figs. 7 and 9 also depict embodiments of eNBs, hardware processing circuitry of eNBs, UEs, and/or hardware processing circuitry of UEs, and the embodiments described with respect to Fig. 6 and Figs. 7 and 9 can operate or function in the manner described herein with respect to any of the figures.

[0074] In addition, although eNB 610 and UE 630 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.

[0075] Fig. 7 illustrates hardware processing circuitries for a UE for LBT for UL transmissions, in accordance with some embodiments of the disclosure. With reference to Fig. 6, a UE may include various hardware processing circuitries discussed herein (such as hardware processing circuitry 700 of Fig. 7), which may in turn comprise logic devices and/or circuitry operable to perform various operations. For example, in Fig. 6, UE 630 (or various elements or components therein, such as hardware processing circuitry 640, or combinations of elements or components therein) may include part of, or all of, these hardware processing circuitries.

[0076] 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 636 (and/or one or more other processors which UE 630 may comprise), memory 638, and/or other elements or components of UE 630 (which may include hardware processing circuitry 640) 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 636 (and/or one or more other processors which UE 630 may comprise) may be a baseband processor.

[0077] Returning to Fig. 7, an apparatus of UE 630 (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 700. In some embodiments, hardware processing circuitry 700 may comprise one or more antenna ports 705 operable to provide various transmissions over a wireless communication channel (such as wireless

communication channel 650). Antenna ports 705 may be coupled to one or more antennas 707 (which may be antennas 625). In some embodiments, hardware processing circuitry 700 may incorporate antennas 707, while in other embodiments, hardware processing circuitry 700 may merely be coupled to antennas 707.

[0078] Antenna ports 705 and antennas 707 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 705 and antennas 707 may be operable to provide transmissions from UE 630 to wireless communication channel 650 (and from there to eNB 610, or to another eNB). Similarly, antennas 707 and antenna ports 705 may be operable to provide transmissions from a wireless communication channel 650 (and beyond that, from eNB 610, or another eNB) to UE 630.

[0079] Hardware processing circuitry 700 may comprise various circuitries operable in accordance with the various embodiments discussed herein. With reference to Fig. 7, hardware processing circuitry 700 may comprise a first circuitry 710, a second circuitry 720, a third circuitry 730, and/or a fourth circuitry 740. In some embodiments, first circuitry 710 may be operable to initiate a single-interval LBT procedure within an initial OFDM symbol of a subframe after a first time period and before a second time period, the single interval LBT procedure having a first duration. Second circuitry 720 may be operable to allocate a second duration within the initial OFDM symbol for a reservation signal. The second duration may span a symbol time of the initial symbol minus the first time period, the first duration, and the second time period.

[0080] Third circuitry 730 may be operable to format the second duration within the initial OFDM symbol for the reservation signal. Fourth circuitry 740 may be operable to detect the second duration within the initial OFDM symbol for the reservation signal. First circuitry 710 may provide signaling for the single-interval LBT procedure to third circuitry 730 over an interface 715. Second circuitry 720 may provide information regarding an allocated second duration to third circuitry 730 over an interface 725. Fourth circuitry 740 may provide information regarding a detected second duration to second circuitry 720 over an interface 745.

[0081] Alternatively, in some embodiments, first circuitry 710 may be operable to initiate a single-interval LBT procedure within an initial OFDM symbol of a subframe, the single interval LBT procedure having a first duration, and second circuitry 720 may be operable to allocate a second duration within the initial OFDM symbol for a reservation signal. The single-interval LBT procedure may follow a first time period, a second time period may follow the single-interval LBT procedure, and the second duration may span a symbol time of the initial symbol minus a sum of the first time period, the first duration, and the second time period.

[0082] In various embodiments, the subframe may be a first subframe, and a second subframe may precede the first subframe. In some embodiments (which may correspond with Fig. 2), the second subframe may be a DL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a following OFDM symbol. For some embodiments (which may correspond with Fig. 3), the second subframe may be a UL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a following OFDM symbol. In some embodiments (which may correspond with Fig. 4), the second subframe may be a DL subframe and the first subframe may be a UL subframe, and the reservation signal may extends an eNB

transmission in a preceding OFDM symbol. For some embodiments, (which may correspond with Fig. 5), the second subframe may be a UL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a preceding OFDM symbol.

[0083] In some embodiments, the first time period may follow an end of a preceding

OFMD symbol, and the second duration may be followed by a beginning of a following OFDM symbol. For some embodiments, the second duration may follow an end of a preceding OFDM symbol, and the second time period may be followed by a beginning of a following OFDM symbol.

[0084] For some embodiments, the first time period may be greater than or equal to a eNB-to-UE maximal channel delay spread time. In some embodiments, the first time period may be greater than or equal to a UE-to-UE maximal channel delay spread time. For some embodiments, wherein the first time period may be greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time.

[0085] In various embodiments, the second time period may be greater than or equal to a UE receiver-to-transmitter switching time.

[0086] Accordingly, in some embodiments (which may correspond with Fig. 2), the first time period may follow an end of a preceding OFMD symbol, the second duration may be followed by a beginning of the following OFDM symbol, the first time period may be greater than or equal to an eNB-to-UE maximal channel delay spread time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time. For some embodiments, (which may correspond with Fig. 3), the first time period may follow an end of a preceding OFMD symbol, the second duration may be followed by a beginning of a following OFDM symbol, the first time period may be greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time. In some embodiments (which may correspond with Fig. 4), the second duration may follow an end of a preceding OFDM symbol, the second time period may be followed by a beginning of a following OFDM symbol, the first time period may be greater than or equal to a eNB-to-UE maximal channel delay spread time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time. For some embodiments (which may correspond with Fig. 5), the second duration may follow an end of a preceding OFDM symbol, the second time period may be followed by a beginning of a following OFDM symbol, the first time period may be greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time.

[0087] In some embodiments, first circuitry 710, second circuitry 720, third circuitry

730, and/or fourth circuitry 740 may be implemented as separate circuitries. In other embodiments, first circuitry 710, second circuitry 720, third circuitry 730, and fourth circuitry 740 may be combined and implemented together in a circuitry without altering the essence of the embodiments.

[0088] Fig. 8 illustrates methods for a UE for LBT for UL transmissions, in accordance with some embodiments of the disclosure. Fig. 9 illustrates methods for a UE for LBT for UL transmissions, in accordance with some embodiments of the disclosure. With reference to Fig. 6, methods that may relate to UE 630 and hardware processing circuitry 640 are discussed herein. Although the actions in the method 800 of Fig. 8 and method 900 of Fig. 9 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 Figs. 8 and 9 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.

[0089] Moreover, in some embodiments, machine readable storage media may have executable instructions that, when executed, cause UE 630 and/or hardware processing circuitry 640 to perform an operation comprising the methods of Figs. 8 and 9. 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 fiash-memory-based storage media), or any other tangible storage media or non-transitory storage media.

[0090] In some embodiments, an apparatus may comprise means for performing various actions and/or operations of the methods of Figs. 8 and 9.

[0091] Returning to Fig. 8, various methods may be in accordance with the various embodiments discussed herein. A method 800 may comprise an initiating 810 and an allocating 815. In initiating 810, a single-interval LBT procedure may be initiated within an initial OFDM symbol of a subframe after a first time period and before a second time period, the single interval LBT procedure having a first duration. In allocating 815, a second duration may be allocated within the initial OFDM symbol for a reservation signal. The second duration may span a symbol time of the initial symbol minus the first time period, the first duration, and the second time period.

[0092] In various embodiments, the subframe may be a first subframe, and a second subframe may precede the first subframe. In some embodiments (which may correspond with Fig. 2), the second subframe may be a DL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a following OFDM symbol. For some embodiments (which may correspond with Fig. 3), the second subframe may be a UL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a following OFDM symbol. In some embodiments (which may correspond with Fig. 4), the second subframe may be a DL subframe and the first subframe may be a UL subframe, and the reservation signal may extends an eNB

[0093] In some embodiments, the first time period may follow an end of a preceding

[0094] For some embodiments, the first time period may be greater than or equal to a eNB-to-UE maximal channel delay spread time. In some embodiments, the first time period may be greater than or equal to a UE-to-UE maximal channel delay spread time. For some embodiments, wherein the first time period may be greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time.

[0095] In various embodiments, the second time period may be greater than or equal to a UE receiver-to-transmitter switching time.

[0096] Returning to Fig. 9, various methods may be in accordance with the various embodiments discussed herein. A method 900 may comprise an initiating 910 and an allocating 915. In initiating 910, a single-interval LBT procedure may be initiated within an initial OFDM symbol of a subframe, the single interval LBT procedure having a first duration. In allocating 915, a second duration may be allocated within the initial OFDM symbol for a reservation signal. The single-interval LBT procedure may follow a first time period, the second time period may follow the single-interval LBT procedure, and the second duration may span a symbol time of the initial symbol minus a sum of the first time period, the first duration, and the second time period.

[0097] In various embodiments, the subframe may be a first subframe, and a second subframe may precede the first subframe.

[0098] In some embodiments (which may correspond with Fig. 2), the second subframe may be a DL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a following OFDM symbol. The first time period may follow an end of a preceding OFMD symbol, the second duration may be followed by a beginning of the following OFDM symbol, the first time period may be greater than or equal to an eNB-to-UE maximal channel delay spread time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time.

[0099] For some embodiments (which may correspond with Fig. 3), the second subframe may be a UL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a following OFDM symbol. The first time period may follow an end of a preceding OFMD symbol, the second duration may be followed by a beginning of a following OFDM symbol, the first time period may be greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time.

[00100] In some embodiments (which may correspond with Fig. 4), the second subframe may be a DL subframe and the first subframe may be a UL subframe, and the reservation signal may extends an eNB transmission in a preceding OFDM symbol. The second duration may follow an end of a preceding OFDM symbol, the second time period may be followed by a beginning of a following OFDM symbol, the first time period may be greater than or equal to a eNB-to-UE maximal channel delay spread time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time.

[00101] For some embodiments, (which may correspond with Fig. 5), the second subframe may be a UL subframe and the first subframe may be a UL subframe, and the reservation signal may extend a UE transmission in a preceding OFDM symbol. The second duration may follow an end of a preceding OFDM symbol, the second time period may be followed by a beginning of a following OFDM symbol, the first time period may be greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time, and the second time period may be greater than or equal to a UE receiver-to-transmitter switching time.

[00102] Fig. 10 illustrates example components of a UE device 1000, in accordance with some embodiments of the disclosure. In some embodiments, a UE device 1000 may include application circuitry 1002, baseband circuitry 1004, Radio Frequency (RF) circuitry 1006, front-end module (FEM) circuitry 1008, a low-power wake-up receiver (LP-WUR), and one or more antennas 1010, coupled together at least as shown. In some embodiments, the UE device 1000 may include additional elements such as, for example, memory /storage, display, camera, sensor, and/or input/output (I/O) interface. [00103] The application circuitry 1002 may include one or more application processors. For example, the application circuitry 1002 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with and/or may include memory /storage and may be configured to execute instructions stored in the memory /storage to enable various applications and/or operating systems to run on the system.

[00104] The baseband circuitry 1004 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 1004 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 1006 and to generate baseband signals for a transmit signal path of the RF circuitry 1006. Baseband processing circuity 1004 may interface with the application circuitry 1002 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 1006. For example, in some embodiments, the baseband circuitry 1004 may include a second generation (2G) baseband processor 1004A, third generation (3G) baseband processor 1004B, fourth generation (4G) baseband processor 1004C, and/or other baseband processor(s) 1004D for other existing generations, generations in development or to be developed in the future (e.g., fifth generation (5G), 6G, etc.). The baseband circuitry 1004 (e.g., one or more of baseband processors 1004A-D) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 1006. 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 1004 may include Fast-Fourier Transform (FFT), precoding, and/or constellation mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry 1004 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.

[00105] In some embodiments, the baseband circuitry 1004 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) 1004E of the baseband circuitry 1004 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) 1004F. The audio DSP(s) 1004F 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 1004 and the application circuitry 1002 may be implemented together such as, for example, on a system on a chip (SOC).

[00106] In some embodiments, the baseband circuitry 1004 may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 1004 may support communication with an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN). Embodiments in which the baseband circuitry 1004 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry.

[00107] RF circuitry 1006 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 1006 may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry 1006 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 1008 and provide baseband signals to the baseband circuitry 1004. RF circuitry 1006 may also include a transmit signal path which may include circuitry to up- convert baseband signals provided by the baseband circuitry 1004 and provide RF output signals to the FEM circuitry 1008 for transmission.

[00108] In some embodiments, the RF circuitry 1006 may include a receive signal path and a transmit signal path. The receive signal path of the RF circuitry 1006 may include mixer circuitry 1006 A, amplifier circuitry 1006B and filter circuitry 1006C. The transmit signal path of the RF circuitry 1006 may include filter circuitry 1006C and mixer circuitry 1006 A. RF circuitry 1006 may also include synthesizer circuitry 1006D for synthesizing a frequency for use by the mixer circuitry 1006A of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 1006 A of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry 1008 based on the synthesized frequency provided by synthesizer circuitry 1006D. The amplifier circuitry 1006B may be configured to amplify the down-converted signals and the filter circuitry 1006C 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 1004 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 1006A of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

[00109] In some embodiments, the mixer circuitry 1006A of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 1006D to generate RF output signals for the FEM circuitry 1008. The baseband signals may be provided by the baseband circuitry 1004 and may be filtered by filter circuitry 1006C. The filter circuitry 1006C may include a low-pass filter (LPF), although the scope of the embodiments is not limited in this respect.

[00110] In some embodiments, the mixer circuitry 1006A of the receive signal path and the mixer circuitry 1006A 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 1006A of the receive signal path and the mixer circuitry 1006A 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 1006 A of the receive signal path and the mixer circuitry 1006 A of the transmit signal path may be arranged for direct down-conversion and/or direct up-conversion, respectively. In some embodiments, the mixer circuitry 1006A of the receive signal path and the mixer circuitry 1006A of the transmit signal path may be configured for super-heterodyne operation.

[00111] In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 1006 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 1004 may include a digital baseband interface to communicate with the RF circuitry 1006. [00112] In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

[00113] In some embodiments, the synthesizer circuitry 1006D may be a fractional -N synthesizer or a fractional N/N+l 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 1006D may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[00114] The synthesizer circuitry 1006D may be configured to synthesize an output frequency for use by the mixer circuitry 1006A of the RF circuitry 1006 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 1006D may be a fractional N/N+l synthesizer.

[00115] In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 1004 or the applications processor 1002 depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the applications processor 1002.

[00116] Synthesizer circuitry 1006D of the RF circuitry 1006 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 (DP A). In some embodiments, the DMD may be configured to divide the input signal by either N or N+l (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.

[00117] In some embodiments, synthesizer circuitry 1006D 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 1006 may include an IQ/polar converter.

[00118] FEM circuitry 1008 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 1010, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 1006 for further processing. FEM circuitry 1008 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 1006 for transmission by one or more of the one or more antennas 1010.

[00119] In some embodiments, the FEM circuitry 1008 may include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include a low-noise amplifier (LNA) to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 1006). The transmit signal path of the FEM circuitry 1008 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 1006), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 1010.

[00120] In some embodiments, the UE 1000 comprises a plurality of power saving mechanisms. If the UE 1000 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.

[00121] If there is no data traffic activity for an extended period of time, then the UE

1000 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 1000 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.

[00122] An additional power saving mode may allow a device to be unavailable to the network for periods longer than a paging interval (ranging from seconds to a few hours). During this time, the device is totally unreachable to the network and may power down completely. Any data sent during this time incurs a large delay and it is assumed the delay is acceptable. [00123] In addition, in various embodiments, an eNB device may include components substantially similar to one or more of the example components of UE device 1000 described herein.

[00124] Reference in the specification to "an embodiment," "one embodiment," "some embodiments," or "other embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments. The various appearances of "an embodiment," "one embodiment," or "some embodiments" are not necessarily all referring to the same embodiments. If the specification states a component, feature, structure, or characteristic "may," "might," or "could" be included, that particular component, feature, structure, or characteristic is not required to be included. If the specification or claim refers to "a" or "an" element, that does not mean there is only one of the elements. If the specification or claims refer to "an additional" element, that does not preclude there being more than one of the additional element.

[00125] Furthermore, the particular features, structures, functions, or characteristics may be combined in any suitable manner in one or more embodiments. For example, a first embodiment may be combined with a second embodiment anywhere the particular features, structures, functions, or characteristics associated with the two embodiments are not mutually exclusive.

[00126] 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 discussed. The embodiments of the disclosure are intended to embrace all such alternatives, modifications, and variations as to fall within the broad scope of the appended claims.

[00127] In addition, well known power/ground connections to integrated circuit (IC) chips and other components may or may not be shown within the presented figures, for simplicity of illustration and discussion, and so as not to obscure the disclosure. Further, arrangements may be shown in block diagram form in order to avoid obscuring the disclosure, and also in view of the fact that specifics with respect to implementation of such block diagram arrangements are highly dependent upon the platform within which the present disclosure is to be implemented (i.e., such specifics should be well within purview of one skilled in the art). Where specific details (e.g., circuits) are set forth in order to describe example embodiments of the disclosure, it should be apparent to one skilled in the art that the disclosure can be practiced without, or with variation of, these specific details. The description is thus to be regarded as illustrative instead of limiting.

[00128] The following examples pertain to further embodiments. Specifics in the examples may be used anywhere in one or more embodiments. All optional features of the apparatus described herein may also be implemented with respect to a method or process.

[00129] Example 1 provides an apparatus of an Evolved Node B (eNB) operable to communicate with a User Equipment (UE) on a wireless network, comprising: one or more processors to: initiate a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency -Division Multiplexing (OFDM) symbol of a subframe after a first time period and before a second time period, a sensing interval within the single interval LBT procedure having a first duration; and allocate a second duration within the OFDM symbol for a reservation signal, wherein the second duration spans a symbol time of the OFDM symbol minus the first time period, the first duration, and the second time period.

[00130] In example 2, the apparatus of example 1 , wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00131] In example 3, the apparatus of example 1 , wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00132] In example 4, the apparatus of example 1 , wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00133] In example 5, the apparatus of example 1 , wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

[00134] In example 6, the apparatus of any of examples 1 , 2, or 3, wherein the first time period follows an end of a preceding OFMD symbol; and wherein the second duration is followed by a beginning of a following OFDM symbol. [00135] In example 7, the apparatus of any of examples 1 , 4, or 5, wherein the second duration follows an end of a preceding OFDM symbol; and wherein the second time period is followed by a beginning of a following OFDM symbol.

[00136] In example 8, the apparatus of any of examples 1 , 2, or 4, wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time.

[00137] In example 9, the apparatus of any of examples 1 , 3, or 5, wherein the first time period is greater than or equal to a UE-to-UE maximal channel delay spread time.

[00138] In example 10, the apparatus of any of examples 1, 3, 5, or 9, wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time.

[00139] In example 11 , the apparatus of any of examples 1 through 5, wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00140] In example 12, the apparatus of any of examples 1 through 1 1, wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol.

[00141] In example 13, the apparatus of any of examples 1 through 1 1, comprising a transceiver circuitry for at least one of: generating transmissions, encoding transmissions, processing transmissions, or decoding transmissions.

[00142] Example 14 provides an Evolved Node B (eNB) 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, the eNB device including the apparatus of any of examples 1 through 13.

[00143] Example 15 provides a method comprising: initiating, for a User Equipment

(UE), a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency- Division Multiplexing (OFDM) symbol of a subframe after a first time period and before a second time period, a sensing interval within the single interval LBT procedure having a first duration; and allocating a second duration within the OFDM symbol for a reservation signal, wherein the second duration spans a symbol time of the OFDM symbol minus the first time period, the first duration, and the second time period.

[00144] In example 16, the method of example 15, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00145] In example 17, the method of example 15, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00146] In example 18, the method of example 15, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00147] In example 19, the method of example 15, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

[00148] In example 20, the method of any of examples 15, 16, or 17, wherein the first time period follows an end of a preceding OFMD symbol; and wherein the second duration is followed by a beginning of a following OFDM symbol.

[00149] In example 21 , the method of any of examples 15, 18, or 19, wherein the second duration follows an end of a preceding OFDM symbol; and wherein the second time period is followed by a beginning of a following OFDM symbol.

[00150] In example 22, the method of any of examples 15, 16, or 18, wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time.

[00151] In example 23, the method of any of examples 15, 17, or 19, wherein the first time period is greater than or equal to a UE-to-UE maximal channel delay spread time.

[00152] In example 24, the method of any of examples 15, 17, 19, or 23, wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time.

[00153] In example 25, the method of any of examples 15 through 19, wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00154] In example 26, the method of any of examples 15 through 25, wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol.

[00155] Example 27provides machine readable storage media having machine executable instructions stored thereon that, when executed, cause one or more processors to perform a method according to any of examples 15 through 26.

[00156] Example 28 provides an apparatus of an Evolved Node B (eNB) operable to communicate with a User Equipment (UE) on a wireless network, comprising: means for initiating a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe after a first time period and before a second time period, a sensing interval within the single interval LBT procedure having a first duration; and means for allocating a second duration within the OFDM symbol for a reservation signal, wherein the second duration spans a symbol time of the OFDM symbol minus the first time period, the first duration, and the second time period.

[00157] In example 29, the apparatus of example 28, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00158] In example 30, the apparatus of example 28, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00159] In example 31 , the apparatus of example 28, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00160] In example 32, the apparatus of example 28, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

[00161] In example 33, the apparatus of any of examples 28, 29, or 30, wherein the first time period follows an end of a preceding OFMD symbol; and wherein the second duration is followed by a beginning of a following OFDM symbol.

[00162] In example 34, the apparatus of any of examples 28, 31, or 32, wherein the second duration follows an end of a preceding OFDM symbol; and wherein the second time period is followed by a beginning of a following OFDM symbol.

[00163] In example 35, the apparatus of any of examples 28, 29, or 31 , wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time.

[00164] In example 36, the apparatus of any of examples 28, 30, or 32, wherein the first time period is greater than or equal to a UE-to-UE maximal channel delay spread time. [00165] In example 37, the apparatus of any of examples 28, 30, 32, or 36, wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time.

[00166] In example 38, the apparatus of any of examples 28 through 32, wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00167] In example 39, the apparatus of any of examples 28 through 38, wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol.

[00168] Example 40 provides machine readable storage media having machine executable instructions that, when executed, cause one or more processors of a User Equipment (UE) operable to communicate with an Evolved Node-B (eNB) on a wireless network to perform an operation comprising: initiate a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe after a first time period and before a second time period, a sensing interval within the single interval LBT procedure having a first duration; and allocate a second duration within the OFDM symbol for a reservation signal, wherein the second duration spans a symbol time of the OFDM symbol minus the first time period, the first duration, and the second time period.

[00169] In example 41 , the machine readable storage media of example 40, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00170] In example 42, the machine readable storage media of example 40, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00171] In example 43, the machine readable storage media of example 40, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00172] In example 44, the machine readable storage media of example 40, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

[00173] In example 45, the machine readable storage media of any of examples 40, 41, or 42, wherein the first time period follows an end of a preceding OFMD symbol; and wherein the second duration is followed by a beginning of a following OFDM symbol.

[00174] In example 46, the machine readable storage media of any of examples 40, 43, or 44, wherein the second duration follows an end of a preceding OFDM symbol; and wherein the second time period is followed by a beginning of a following OFDM symbol.

[00175] In example 47, the machine readable storage media of any of examples 40, 41, or 43, wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time.

[00176] In example 48, the machine readable storage media of any of examples 40, 42, or 44, wherein the first time period is greater than or equal to a UE-to-UE maximal channel delay spread time.

[00177] In example 49, the machine readable storage media of any of examples 40, 42,

44, or 48, wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time.

[00178] In example 50, the machine readable storage media of any of examples 40 through 44, wherein the second time period is greater than or equal to a UE receiver-to- transmitter switching time.

[00179] In example 51 , the machine readable storage media of any of examples 40 through 50, wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol.

[00180] Example 52 provides an apparatus of an Evolved Node B (eNB) operable to communicate with a User Equipment (UE) on a wireless network, comprising: one or more processors to: initiate a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency -Division Multiplexing (OFDM) symbol of a subframe, a sensing interval within the single interval LBT procedure having a first duration; and allocate a second duration within the OFDM symbol for a reservation signal, wherein the sensing interval within the single-interval LBT procedure follows a first time period; wherein a second time period follows the sensing interval within the single-interval LBT procedure; and wherein the second duration spans a symbol time of the OFDM symbol minus a sum of the first time period, the first duration, and the second time period. [00181] In example 53, the apparatus of example 52, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00182] In example 54, the apparatus of either of examples 52 or 53, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of the following OFDM symbol; wherein the first time period is greater than or equal to an eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00183] In example 55, the apparatus of example 52, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00184] In example 56, the apparatus of either of examples 52 or 55, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00185] In example 57, the apparatus of example 52, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00186] In example 58, the apparatus of either of examples 52 or 57, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00187] In example 59, the apparatus of example 52, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol. [00188] In example 60, the apparatus of either of examples 52 or 59, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00189] In example 61 , the apparatus of any of examples 52 through 60, wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol.

[00190] In example 62, the apparatus of any of examples 52 through 60, comprising a transceiver circuitry for at least one of: generating transmissions, encoding transmissions, processing transmissions, or decoding transmissions.

[00191] Example 63 provides an Evolved Node B (eNB) 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, the eNB device including the apparatus of any of examples 1 through 62.

[00192] Example 64 provides a method comprising: initiating, for an Evolved Node-B

(eNB), a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal

Frequency-Division Multiplexing (OFDM) symbol of a subframe, a sensing interval within the single interval LBT procedure having a first duration; and allocating a second duration within the OFDM symbol for a reservation signal, wherein the sensing interval within the single-interval LBT procedure follows a first time period; wherein a second time period follows the sensing interval within the single-interval LBT procedure; and wherein the second duration spans a symbol time of the OFDM symbol minus a sum of the first time period, the first duration, and the second time period.

[00193] In example 65, the method of example 64, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00194] In example 66, the method of either of examples 64 or 65, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of the following OFDM symbol; wherein the first time period is greater than or equal to an eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time. [00195] In example 67, the method of example 64, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00196] In example 68, the method of either of examples 64 or 67, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00197] In example 69, the method of example 64, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00198] In example 70, the method of either of examples 64 or 69, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00199] In example 71, the method of example 64, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

[00200] In example 72, the method of either of examples 64 or 71, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00201] In example 73, the method of any of examples 64 through 71 , wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol. [00202] Example 74 provides machine readable storage media having machine executable instructions stored thereon that, when executed, cause one or more processors to perform a method according to any of examples 64 through 73.

[00203] Example 75 provides an apparatus of an Evolved Node B (eNB) operable to communicate with a User Equipment (UE) on a wireless network, comprising: means for initiating a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe, a sensing interval within the single interval LBT procedure having a first duration; and means for allocating a second duration within the OFDM symbol for a reservation signal, wherein the sensing interval within the single-interval LBT procedure follows a first time period; wherein a second time period follows the sensing interval within the single-interval LBT procedure; and wherein the second duration spans a symbol time of the OFDM symbol minus a sum of the first time period, the first duration, and the second time period.

[00204] In example 76, the apparatus of example 75, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00205] In example 77, the apparatus of either of examples 75 or 76, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of the following OFDM symbol; wherein the first time period is greater than or equal to an eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00206] In example 78, the apparatus of example 75, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00207] In example 79, the apparatus of either of examples 75 or 78, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00208] In example 80, the apparatus of example 75, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00209] In example 81, the apparatus of either of examples 75 or 80, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00210] In example 82, the apparatus of example 75, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

[00211] In example 83, the apparatus of either of examples 75 or 82, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00212] In example 84, the apparatus of any of examples 75 through 82, wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol.

[00213] Example 85 provides machine readable storage media having machine executable instructions that, when executed, cause one or more processors of a User Equipment (UE) operable to communicate with an Evolved Node-B (eNB) on a wireless network to perform an operation comprising: initiate a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe, a sensing interval within the single interval LBT procedure having a first duration; and allocate a second duration within the OFDM symbol for a reservation signal, wherein the sensing interval within the single-interval LBT procedure follows a first time period; wherein a second time period follows the sensing interval within the single-interval LBT procedure; and wherein the second duration spans a symbol time of the OFDM symbol minus a sum of the first time period, the first duration, and the second time period.

[00214] In example 86, the machine readable storage media of example 85, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00215] In example 87, the machine readable storage media of either of examples 85 or

86, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of the following OFDM symbol; wherein the first time period is greater than or equal to an eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00216] In example 88, the machine readable storage media of example 85, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a following OFDM symbol.

[00217] In example 89, the machine readable storage media of either of examples 85 or

88, wherein the first time period follows an end of a preceding OFMD symbol; wherein the second duration is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00218] In example 90, the machine readable storage media of example 85, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

[00219] In example 91, the machine readable storage media of either of examples 85 or

90, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to a eNB-to-UE maximal channel delay spread time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00220] In example 92, the machine readable storage media of example 85, wherein the subframe is a first subframe; wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

[00221] In example 93, the machine readable storage media of either of examples 85 or

92, wherein the second duration follows an end of a preceding OFDM symbol; wherein the second time period is followed by a beginning of a following OFDM symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

[00222] In example 94, the machine readable storage media of any of examples 85 through 92, wherein the reservation signal comprises an extended Cyclic Prefix (CP) of a following OFDM symbol.

[00223] In example 95, the apparatus of any of examples 1 through 11 and 52 through

60, wherein the one or more processors comprise a baseband processor.

[00224] In example 96, the apparatus of any of examples 1 through 11 and 52 through

60, comprising a memory for storing instructions, the memory being coupled to the one or more processors.

[00225] In example 97, the apparatus of any of examples 1 through 11 and 52 through

60, comprising a transceiver circuitry for generating transmissions and processing transmissions.

[00226] An abstract is provided that will allow the reader to ascertain the nature and gist of the technical disclosure. The abstract is submitted with the understanding that it will not be used to limit the scope or meaning of the claims. The following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment.

Claims

CLAIMS We claim:

1. An apparatus of an Evolved Node-B (eNB) operable to communicate with a User

Equipment (UE) on a wireless network, comprising:

one or more processors to:

initiate a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe after a first time period and before a second time period, a sensing interval within the single interval LBT procedure having a first duration; and

allocate a second duration within the OFDM symbol for a reservation signal, wherein the second duration spans a symbol time of the OFDM symbol minus the first time period, the first duration, and the second time period.

2. The apparatus of claim 1 ,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and

wherein the reservation signal extends a UE transmission in a following OFDM

symbol.

3. The apparatus of claim 1 ,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and

wherein the reservation signal extends a UE transmission in a following OFDM

symbol.

4. The apparatus of claim 1 ,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe; wherein the second subframe is a Downlink (DL) subframe and the first subframe is an Uplink (UL) subframe; and

wherein the reservation signal extends an eNB transmission in a preceding OFDM symbol.

5. The apparatus of claim 1,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

wherein the reservation signal extends a UE transmission in a preceding OFDM

symbol.

6. The apparatus of claim 1,

wherein the first time period follows an end of a preceding OFMD symbol; and wherein the second duration is followed by a beginning of a following OFDM

symbol.

7. Machine readable storage media having machine executable instructions that, when

executed, cause one or more processors of a User Equipment (UE) operable to communicate with an Evolved Node-B (eNB) on a wireless network to perform an operation comprising:

8. The machine readable storage media of claim 7,

wherein the subframe is a first subframe;

wherein the reservation signal extends a UE transmission in a following OFDM symbol.

9. The machine readable storage media of claim 7,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

10. The machine readable storage media of claim 7,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

1 1. The machine readable storage media of claim 7,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

wherein the reservation signal extends a UE transmission in a preceding OFDM symbol.

12. The machine readable storage media of claim 7,

symbol.

13. An apparatus of an Evolved Node-B (eNB) operable to communicate with a User Equipment (UE) on a wireless network, comprising:

one or more processors to:

initiate a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe, a sensing interval within the single interval LBT procedure having a first duration; and allocate a second duration within the OFDM symbol for a reservation signal, wherein the sensing interval within the single-interval LBT procedure follows a first time period;

wherein a second time period follows the sensing interval within the single-interval LBT procedure; and

wherein the second duration spans a symbol time of the OFDM symbol minus a sum of the first time period, the first duration, and the second time period.

14. The apparatus of claim 13,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

wherein the reservation signal extends a UE transmission in a following OFDM

symbol.

15. The apparatus of claim 13,

wherein the first time period follows an end of a preceding OFMD symbol;

wherein the second duration is followed by a beginning of the following OFDM

symbol;

wherein the first time period is greater than or equal to an eNB-to-UE maximal

channel delay spread time; and

wherein the second time period is greater than or equal to a UE receiver-to-transmitter switching time.

16. The apparatus of claim 13,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe; wherein the second subframe is an Uplink (UL) subframe and the first subframe is a UL subframe; and

wherein the reservation signal extends a UE transmission in a following OFDM

symbol.

17. The apparatus of claim 13,

wherein the first time period follows an end of a preceding OFMD symbol;

wherein the second duration is followed by a beginning of a following OFDM

symbol;

wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and

18. The apparatus of claim 13,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

19. Machine readable storage media having machine executable instructions that, when

initiate a single-interval Listen-Before-Talk (LBT) procedure within an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a subframe, a sensing interval within the single interval LBT procedure having a first duration; and allocate a second duration within the OFDM symbol for a reservation signal, wherein the sensing interval within the single-interval LBT procedure follows a first time period; wherein a second time period follows the sensing interval within the single-interval LBT procedure; and

20. The machine readable storage media of claim 19,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

wherein the reservation signal extends a UE transmission in a following OFDM

symbol.

21. The machine readable storage media of claim 19,

wherein the first time period follows an end of a preceding OFMD symbol;

wherein the second duration is followed by a beginning of the following OFDM

symbol;

wherein the first time period is greater than or equal to an eNB-to-UE maximal

channel delay spread time; and

22. The machine readable storage media of claim 19,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;

wherein the reservation signal extends a UE transmission in a following OFDM

symbol.

23. The machine readable storage media of claim 19,

wherein the first time period follows an end of a preceding OFMD symbol;

wherein the second duration is followed by a beginning of a following OFDM

symbol; wherein the first time period is greater than or equal to the greater of: a UE-to-UE maximal channel delay spread time, or a UE transmitter-to-receiver switching time; and

24. The machine readable storage media of claim 19,

wherein the subframe is a first subframe;

wherein a second subframe precedes the first subframe;