CN114070540B - Method, apparatus and storage medium for coexistence of unlicensed uplink and scheduled transmissions - Google Patents

Abstract

Disclosed herein is an apparatus of a User Equipment (UE) configured to communicate with an evolved node B (eNB). The UE may include a memory and processing circuitry coupled to the memory. The processing circuitry may be configured to decode control information received over one or more channels of the unlicensed spectrum. The control information includes an indication that unlicensed Uplink (UL) transmissions are allowed without a prior UL grant. The processing circuit is further configured to perform a Listen Before Talk (LBT) procedure on one or more channels of the unlicensed spectrum to determine whether one of the channels is available. When it is determined that the channel is available, the processing circuitry may encode UL control information and data for transmission using an unlicensed UL transmission. An unlicensed uplink transmission is an unscheduled transmission performed on a channel without a UL grant.

Description

Method, apparatus and storage medium for coexistence of unlicensed uplink and scheduled transmissions

Priority statement

The present application claims priority from U.S. provisional patent application No.62/311,698 entitled "enable CO-EXISTENCE OF AUTONOMOUS UPLINK TRANSMISSION WITH SCHEDULED TRANSMISSION AT ENB (ENABLING coexistence of autonomous uplink transmissions with scheduled transmissions at an eNB)" filed on month 3 and 22 of 2016, which is incorporated herein by reference in its entirety.

The present application is a divisional application of the inventive patent application with international application date 2017, 3-21, international application number PCT/US 2017/023954, national application number 201780012867.0, and the name "coexistence of unlicensed uplink and scheduled transmissions".

Technical Field

Embodiments relate to wireless communications. Some embodiments relate to wireless networks including 3GPP (third generation partnership project) networks, 3GPP LTE (long term evolution) networks, 3GPP LTE-a (LTE advanced) networks, multewire networks, and 5G networks, although the scope of the embodiments is not limited in this respect. Some embodiments relate to unlicensed (or autonomous) uplink transmissions (GULs) for User Equipments (UEs). Some embodiments relate to enabling coexistence of unlicensed (or autonomous) uplink transmissions with scheduled transmissions.

Background

As different types of devices communicating with various network devices increase, the use of 3GPP LTE systems is also increasing. The penetration of mobile devices (user equipment or UEs) in modern society is continually driving the need for a wide variety of networking devices in many different environments. The use of networked UEs using 3GPP LTE systems is increasing in various areas of home and work and life. Fifth generation (5G) wireless systems are forthcoming and are expected to achieve higher speeds, connectivity and availability.

LTE and LTE-advanced are standards for wireless communication of high speed data for User Equipment (UE), such as mobile phones. In LTE-advanced and various wireless systems, carrier aggregation is a technique in which multiple carrier signals operating on different frequencies may be used to carry communications for a single UE, thereby increasing the bandwidth available to a single device. In some embodiments, carrier aggregation may be used in cases where one or more component carriers operate on unlicensed frequencies.

Explosive wireless traffic growth has led to a need to increase the rate. With mature physical layer technology, further improvement of spectral efficiency would be trivial. On the other hand, insufficient licensed spectrum in the low frequency band results in a lack of strength in the data rate improvement. Thus, there is an interest in the operation of LTE systems in unlicensed spectrum. Thus, an important improvement for LTE in 3gpp Release 13 has allowed its operation in unlicensed spectrum via Licensed Assisted Access (LAA), which extends system bandwidth by exploiting the flexible Carrier Aggregation (CA) framework introduced by LTE-advanced systems. The Rel-13LAA system focuses on the design of DL operation over unlicensed spectrum via CA, while the Rel-14 modified LAA (eLAA) system focuses on the design of UL operation over unlicensed spectrum via CA. More improved operation of LTE systems in unlicensed spectrum is expected in future releases and 5G systems. Possible LTE operations in unlicensed spectrum include, and are not limited to, LTE operations in unlicensed spectrum via Dual Connectivity (DC), or DC-based LAA and separate LTE systems in unlicensed spectrum, where LTE-based technology operates only in unlicensed spectrum without the need for an "anchor" in licensed spectrum, which technology is known as multewire. Multewire combines the performance advantages of LTE technology with the simplicity of Wi-Fi like deployment, and is seen as a very important technical component to meet the ever-increasing wireless traffic.

Drawings

In the drawings, which are not necessarily drawn to scale, like numerals may represent like components in different views. Like numerals having different letter suffixes may represent different instances of detailed components. In the following illustrations in the drawings, some embodiments are shown by way of example and not by way of limitation.

As used herein, the terms "autonomous uplink transmission" and "unlicensed uplink transmission" are interchangeable.

Fig. 1 is a block diagram of a system including an evolved node B (eNB) and a User Equipment (UE) that may operate in a wireless communication network, according to some embodiments described herein.

Fig. 2 is a block diagram of a User Equipment (UE) according to some embodiments.

Fig. 3 is a block diagram of an evolved node B (eNB) in accordance with some embodiments.

Fig. 4 illustrates an unlicensed uplink transmission (GUL) according to an example embodiment.

Fig. 5 illustrates an example unlicensed UL transmission (GUL) within a restricted timing window, according to an example embodiment.

Fig. 6A and 6B illustrate example Downlink (DL) transmissions after unlicensed UL transmissions according to example embodiments.

Fig. 6C illustrates an example Downlink (DL) transmission after requesting an acknowledged unlicensed UL transmission, according to an example embodiment.

Fig. 7 and 8 are flowcharts illustrating example functions for implementing unlicensed uplink transmissions in accordance with some embodiments.

Fig. 9 illustrates a block diagram of a communication device, such as an eNB or UE, in accordance with some embodiments.

Detailed Description

Embodiments relate to systems, devices, apparatuses, assemblies, methods, and computer-readable media for improving wireless communications, and more particularly to communication systems that operate in conjunction with carrier aggregation, licensed Assisted Access (LAA), improved LAA (eLAA), and multewire communications. The following description and the drawings illustrate specific embodiments that enable those skilled in the art to practice them. Other embodiments may involve structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in or substituted for those of others and are intended to encompass all available equivalents of the elements described.

Fig. 1 is a block diagram of a system including an evolved node B (eNB) and a User Equipment (UE) that may operate in a wireless communication network, according to some embodiments described herein. The wireless network system 100 includes a UE 104 and an eNB 120 connected via an air interface 190. The UE 104 and eNB 120 communicate using a system that supports Carrier Aggregation (CA) and uses unlicensed bands (unlicensed frequency band) such that the air interface 190 supports multiple frequency carriers and licensed and unlicensed bands. Component carrier 180 and component carrier 185 are shown in fig. 1. Although two component carriers are shown, various embodiments may include any number of two or more component carriers. Various embodiments may operate with any number of licensed channels and any number of unlicensed channels.

Further, in the various embodiments described herein, at least one of the component carriers 180, 185 in the air interface 190 comprises a carrier operating on an unlicensed frequency, referred to herein as an unlicensed carrier. An "unlicensed carrier" or "unlicensed frequency" refers to a range of radio spectrum that is not specifically reserved for use by a system. For example, some frequency ranges may be used by communication systems operating in different communication standards, such as frequency bands used by both the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard (e.g., "WiFi") and the third generation partnership project (3 GPP) standard, including LTE and LTE-advanced and enhanced versions of LTE (discussed below). In contrast, a "licensed channel" or "licensed spectrum" operates under a particular standard, and there is limited concern that other undesirable signals operating under different standards will be present.

Communications over an LTE network may be divided into 10ms frames, each containing ten 1ms subframes. Each subframe may in turn contain two 0.5ms slots. Each slot may contain 6-7 symbols, depending on the system used. A Resource Block (RB), which may also be referred to as a Physical Resource Block (PRB), may be the smallest resource unit that may be allocated to a UE. The resource blocks may be 180kHz wide in frequency and 1 slot long in time. In frequency, a resource block may be 12 subcarriers of 15kHz or 24 subcarriers of 7.5kHz wide. For most channels and signals, 12 subcarriers may be used per resource block. In Frequency Division Duplex (FDD) mode, the uplink and downlink frames may both be 10ms and may be spaced apart in frequency (full duplex) or time (half duplex). In Time Division Duplex (TDD) mode, uplink and downlink subframes may be transmitted on the same frequency and may be multiplexed in the time domain. A downlink resource grid (grid) may be used for downlink transmissions from the eNB to the UE. The resource grid may be a time-frequency resource grid, which is a physical resource in the downlink in each time slot. Each column and each row of the resource grid may correspond to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain may correspond to one slot. The smallest time-frequency unit in a resource grid may be represented by a resource element. Each resource grid may include a plurality of the above-described resource blocks that describe a mapping of particular physical channels to resource elements. Each resource block may include 12 (subcarriers) ×14 (symbols) =168 resource elements.

In some embodiments, downlink resource bins may be used for downlink transmissions from eNB 120 to UE 104, while uplink transmissions from UE 104 to eNB 120 may utilize similar techniques. The resource grid may be a time-frequency resource grid, referred to as a resource grid or a time-frequency resource grid, which is a physical resource in each downlink in each time slot. Such a representation of the time-frequency plane is a common usage of OFDM systems, making it intuitive for radio resource allocation. Each column and each row of the resource grid may correspond to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain may correspond to one slot of a radio frame. The smallest time-frequency unit in the resource grid may be represented by a Resource Element (RE). Each resource grid includes a plurality of Resource Blocks (RBs) that describe a mapping of particular physical channels to resource elements. Each resource block includes a set of resource elements in the frequency domain and may represent a minimum amount of resources that may be currently allocated. There are several different physical downlink channels transmitted using such resource blocks. Two example physical downlink channels are a physical downlink shared channel and a physical downlink control channel.

There may be several different physical downlink channels transmitted using such resource blocks. Two of these physical downlink channels may be a Physical Downlink Control Channel (PDCCH) and a Physical Downlink Shared Channel (PDSCH). Each subframe may be divided into a PDCCH and a PDSCH.

The Physical Downlink Shared Channel (PDSCH) carries user data and higher layer signaling to the UE 104. The Physical Downlink Control Channel (PDCCH) carries information on the transport format and resource allocation associated with the PDSCH channel, etc. It also informs the UE 104 about transport format, resource allocation and hybrid automatic repeat request (HARQ) information related to the uplink shared channel. In general, downlink scheduling (e.g., allocation of control and shared channel resources to UEs 104 within a cell) may be performed at the eNB 120 based on channel quality information fed back from the UEs 104 to the eNB 120, and then the downlink resource allocation information may be transmitted to the UEs 104 on a control channel (PDCCH) for (allocated to) the UEs 104.

The PDCCH transmits control information using CCEs (control channel elements). The PDCCH complex-valued symbols are first organized into four groups before being mapped to resource elements, and then sequence-changed using a sub-block interleaver for rate matching. Each PDCCH is transmitted using one or more of these Control Channel Elements (CCEs), where each CCE corresponds to nine groups of four physical resource elements called Resource Element Groups (REGs). Four QPSK symbols are mapped to each REG. Depending on the size of Downlink Control Information (DCI) and channel conditions, a PDCCH may be transmitted using one or more CCEs. Four or more different PDCCH formats with different numbers of CCEs may be defined in LTE (e.g., aggregation level, l=1, 2, 4, or 8).

The embodiments described herein may fall within the scope of separate systems in the unlicensed spectrum (unlicensed spectrum), including but not limited to Multewire (MF), LAA systems (e.g., eLAA) that allow the next version of UL operation to be implemented, 5G unlicensed systems, and DC-based LAA systems. The unlicensed band of current interest in 3GPP is the 5GHz band, which has a broad spectrum that is universal throughout the world. The 5GHz band in the united states is governed by Unlicensed National Information Infrastructure (UNII) rules of the Federal Communications Commission (FCC). The main existing system in the 5GHz band is a Wireless Local Area Network (WLAN), especially a communication network based on IEEE 802.11a/n/ac technology. Since WLAN systems are widely deployed by individuals and operators for carrier-level access traffic and data offloading, listen-Before-Talk (LBT) is considered a mandatory feature of Rel-13 LAA and Rel-14 eLAA systems to achieve good coexistence with existing systems.

LBT is a procedure in which a radio transmitter first perceives the medium and transmits only when the medium is perceived as idle. In an example, the scheduling-based UL LAA design may include UL PUSCH transmission based on explicit UL grant transmission via PDCCH (e.g., via DCI format 0A/0B). UL grant transmission is performed on the component carrier on which PUSCH transmission is expected after LBT procedure is completed at the eNB. After receiving the UL grant, the scheduled UE expects to perform short-term LBT or type 4 (Cat 4) LBT during the allocated time interval. If LBT is successful at the scheduled UE, the UE may send PUSCH on the resources indicated by the UL grant.

However, since LBT is required on both the eNB side (e.g., when transmitting UL grants) and the scheduled UE side (e.g., prior to transmission of the UE), UL performance within the unlicensed spectrum (e.g., exclusively during multewire operation within the unlicensed spectrum) may become very poor. In the case where a scheduled system (e.g., an LTE-based system) is co-located with an unscheduled autonomous system (i.e., wi-Fi), performance degradation may typically occur. In some instances, LTE-based systems may also use a 4-subframe processing delay, so that the first 4 subframes in a transmission burst cannot be configured for UL, as UL grants are not available for those subframes within the same transmission burst. The 4 subframe delay requirement may also result in processing delays for LTE systems operating in unlicensed spectrum.

In an example embodiment, to improve communication system performance in unlicensed spectrum (e.g., due to LBT requirements on both sides and 4 subframe processing delay), the UE may perform unlicensed UL transmission (grantless UL transmission) without the eNB transmitting UL grants for PUSCH transmissions by the UE. In view of this, the requirement for LBT on both sides may be reduced when unlicensed UL transmission of the UE occurs, because the eNB will not perform LBT and LBT may be performed by the UE only. Since the UE performing the unlicensed UL transmission does not need to wait for UL grant by the eNB, the additional 4 subframe delay of accessing the channel for UL transmission will also be eliminated, thereby facilitating further performance improvement.

The coexisting embodiments described herein may operate within wireless network system 100. In the wireless network system 100, the UE 104 and any other UE in the system may be, for example, a laptop, a smart phone, a tablet, a printer, a machine type device such as a smart meter or a dedicated device for health monitoring, a remote security monitoring system, a smart transportation system, or any other wireless device with or without a user interface. The eNB 120 provides network connectivity for the UE 104 to a larger network (not shown). Connectivity for the UE 104 is provided via an air interface 190 within an eNB service area provided by the eNB 120. In some embodiments, such a larger network may be a wide area network operated by a cellular network provider, or may be the internet. Each eNB service area associated with an eNB 120 is supported by antennas integrated with the eNB 120. The service area may be divided into a plurality of sectors associated with a particular antenna. These sectors may be physically associated with fixed antennas or may be allocated to physical areas, and the tunable antennas or antenna settings may be adjusted during beamforming to direct signals to specific sectors. For example, one embodiment of eNB 120 includes three sectors, each covering a 120 degree area with an antenna array directed to each sector to provide 360 degree coverage around eNB 120.

The UE 104 includes control circuitry 105 coupled with transmit circuitry 110 and receive circuitry 115. The transmit circuitry 110 and the receive circuitry 115 may each be coupled to one or more antennas. The control circuit 105 may be adapted to perform operations associated with wireless communications using carrier aggregation. The transmitting circuit 110 and the receiving circuit 115 may be adapted to transmit and receive data, respectively. The control circuitry 105 may be adapted or configured to perform various operations such as those described elsewhere in this disclosure in connection with the UE. The transmission circuit 110 may transmit a plurality of multiplexed uplink physical channels. The plurality of uplink physical channels may be multiplexed according to Time Division Multiplexing (TDM) or Frequency Division Multiplexing (FDM) and carrier aggregation. The transmit circuit 110 may be configured to receive block data from the control circuit 105 for transmission over the air interface 190. Similarly, the receive circuitry 115 may receive a plurality of multiplexed downlink physical channels from the air interface 190 and relay the physical channels to the control circuitry 105. The uplink physical channels and the downlink physical channels may be multiplexed according to FDM. The transmitting circuit 110 and the receiving circuit 115 may transmit and receive control data and content data (e.g., messages, images, video, etc.), which are structured within blocks of data transmitted by the physical channel.

Fig. 1 also illustrates an eNB 120 in accordance with various embodiments. The eNB 120 circuitry may include control circuitry 155 coupled with transmit circuitry 160 and receive circuitry 165. The transmit circuitry 160 and receive circuitry 165 may each be coupled to one or more antennas that may be used to enable communications via the air interface 190.

The control circuitry 155 may be adapted to perform operations for managing the channels and component carriers used in connection with the respective UEs. The transmit circuitry 160 and receive circuitry 165 may be adapted to transmit data to and receive data from, respectively, any UE connected to the eNB 120. The transmission circuit 160 may transmit a downlink physical channel including a plurality of downlink subframes. The reception circuitry 165 may receive a plurality of uplink physical channels from respective UEs including the UE 104. The plurality of uplink physical channels may be multiplexed according to FDM and using carrier aggregation.

As described above, communications over the air interface 190 may use carrier aggregation, where multiple different component carriers 180, 185 may be aggregated to carry information between the UE 104 and the eNB 120. Such component carriers 180, 185 may have different bandwidths and may be used for uplink communications from UE 104 to eNB 120, downlink communications from eNB 120 to UE 104, or both. Such component carriers 180, 185 may cover similar areas or may cover different but overlapping sectors. A Radio Resource Control (RRC) connection may be handled by only one of the component carrier units, which may be referred to as a primary (primary) component carrier, and the other component carriers as secondary component carriers. In some embodiments, the primary component carrier is provided by a primary cell (PCell) and may operate in a licensed band to provide efficient collision-free communication. The primary channel may be used to schedule other channels including unlicensed channels. In view of this, the PCell is the primary cell with which the UE 104 communicates and maintains its connection with the network.

In an example, one or more secondary cells (scells) may also be activated and allocated to UEs supporting carrier aggregation using licensed and unlicensed bands (e.g., based on UL and DL communications of the eLAA).

In operation, the wireless communication network 100 may include the capability to support communication over licensed spectrum by the eNodeB 120 and the UE 104. The wireless communication network 100 may also include the capability to support communication between the eNodeB 120 and the UE 104 over unlicensed spectrum (e.g., one or more 5GHz bands). In some examples where transmissions are made simultaneously over licensed and unlicensed spectrum, the licensed spectrum transmission may be a primary cell (PCell) transmission and the unlicensed spectrum transmission may be a secondary cell (SCell) transmission. For communication on PCell and SCell, the wireless communication network 100 may use a self-contained frame structure in which control signaling and data may be transmitted in a Time Division Multiplexed (TDM) manner with a single subframe.

In some embodiments, the wireless communication network 100 may include the capability to support the eNodeB 120 and the UE 104 to communicate only over unlicensed spectrum (e.g., multewire communications). Furthermore, the UE may be configured to perform unlicensed uplink transmissions, as will be described in more detail with reference to fig. 4-9.

As used herein, the term circuit may refer to, include, or be part of the following components: an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), or memory (shared, dedicated, or group) that executes one or more software or firmware programs, a combinational logic circuit, or other suitable hardware components that provide the described functionality. In some embodiments, the circuitry may be implemented in or the functionality associated with one or more software or firmware modules. In some embodiments, the circuitry may include logic that may operate at least in part in hardware. The embodiments described herein may be implemented into a system using any suitable configuration of hardware or software.

Fig. 2 is a functional diagram of a User Equipment (UE) according to some embodiments. The UE 200 may be suitable for use as the UE 104 shown in fig. 1. In some embodiments, the UE 200 may include application circuitry 202, baseband circuitry 204, radio Frequency (RF) circuitry 206, front End Module (FEM) circuitry 208, and one or more antennas 210A-210D coupled together at least as shown. In some embodiments, other circuits or arrangements may include one or more elements or components of the application circuitry 202, baseband circuitry 204, RF circuitry 206, or FEM circuitry 208, and may also include other elements or components in some cases. As an example, a "processing circuit" may include one or more elements or components, some or all of which may be included in the application circuit 202 or the baseband circuit 204. As another example, a "transceiver circuit" may include one or more elements or components, some or all of which may be included in the RF circuit 206 or FEM circuit 208. However, these examples are not limiting, as in some cases the processor circuit or transceiver circuit may also include other elements or components.

The application circuitry 202 may include one or more application processors. For example, application circuitry 202 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 special-purpose processors (e.g., graphics processors, application processors, etc.). The processor may be coupled with 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 to implement one or more of the functions described herein.

The baseband circuitry 204 may include circuitry such as, but not limited to: one or more single-core or multi-core processors. The baseband circuitry 204 may include one or more baseband processors or control logic to process baseband signals received from the receive signal path of the RF circuitry 206 and to generate baseband signals for the transmit signal path of the RF circuitry 206. The baseband processing circuit 204 may interface with the application circuit 202 to generate and process baseband signals and control the operation of the RF circuit 206. For example, in some embodiments, the baseband circuitry 204 may include a second generation (2G) baseband processor 204a, a third generation (3G) baseband processor 204b, a fourth generation (4G) baseband processor 204c, or one or more other baseband processors 204d for other existing generations, generations to be developed in or about to be developed in the future (e.g., fifth generation (5G), 6G, etc.). The baseband circuitry 204 (e.g., one or more of the baseband processors 204a-204 d) may handle various radio control functions that support communication with one or more radio networks via the RF circuitry 206. The radio control functions may include, but are not limited to: signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, the modulation/demodulation circuitry of baseband circuitry 204 may include FFT, precoding, or constellation mapping/demapping functions. In some embodiments, the encoding/decoding circuitry of baseband circuitry 204 may include Low Density Parity Check (LDPC) encoder/decoder functionality, and optionally some other techniques, such as block codes, convolutional codes, turbo codes, etc., which may be used to support legacy protocols. Embodiments of the modem and encoder/decoder functions are not limited to these examples and may include other suitable functions in other embodiments.

In some embodiments, baseband circuitry 204 may include elements of a protocol stack, such as elements of an evolved universal terrestrial radio access network (E-UTRAN) protocol, including, for example: physical (PHY), medium Access Control (MAC), radio Link Control (RLC), packet Data Convergence Protocol (PDCP), or Radio Resource Control (RRC) elements. The Central Processing Unit (CPU) 204e of the baseband circuitry 204 may be configured to run elements of the protocol stack for PHY, MAC, RLC, PDCP, and/or RRC layer signaling. In some embodiments, the baseband circuitry may include one or more audio Digital Signal Processors (DSPs) 204f. One or more of the audio DSPs 204f may include elements for compression/decompression and echo cancellation, and may include other suitable processing elements in other embodiments. In some embodiments, components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on the same circuit board. In some embodiments, some or all of the constituent components of baseband circuitry 204 and application circuitry 202 may be implemented together, for example, on a system on a chip (SOC).

In some embodiments, baseband circuitry 204 may provide communications compatible with one or more radio technologies. For example, in some embodiments, baseband circuitry 204 may support communication with an Evolved Universal Terrestrial Radio Access Network (EUTRAN) or other Wireless Metropolitan Area Network (WMAN), a Wireless Local Area Network (WLAN), a Wireless Personal Area Network (WPAN). An embodiment in which the baseband circuitry 204 is configured to support radio communications for multiple wireless protocols may be referred to as a multimode baseband circuitry.

The RF circuitry 206 may support communication with a wireless network using modulated electromagnetic radiation through a non-solid medium. In various embodiments, RF circuitry 206 may include switches, filters, amplifiers, and the like to facilitate communication with a wireless network. RF circuitry 206 may include a receive signal path that may include circuitry to down-convert RF signals received from FEM circuitry 208 and provide baseband signals to baseband circuitry 204. RF circuitry 206 may also include transmit signal paths that may include circuitry to up-convert baseband signals provided by baseband circuitry 204 and provide RF output signals to FEM circuitry 208 for transmission.

In some embodiments, RF circuitry 206 may include a receive signal path and a transmit signal path. The receive signal path of RF circuit 206 may include a mixer circuit 206a, an amplifier circuit 206b, and a filter circuit 206c. The transmit signal path of RF circuit 206 may include a filter circuit 206c and a mixer circuit 206a. The RF circuitry 206 may also include synthesizer circuitry 206d for synthesizing frequencies for use by the mixer circuitry 206a of the receive signal path and the transmit signal path. In some embodiments, the mixer circuit 206a of the receive signal path may be configured to down-convert the RF signal received from the FEM circuit 208 based on the synthesized frequency provided by the synthesizer circuit 206 d. The amplifier circuit 206b may be configured to amplify the down-converted signal and the filter circuit 206c may be a Low Pass Filter (LPF) or a Band Pass Filter (BPF) configured to remove unwanted signals from the down-converted signal to generate an output baseband signal. The output baseband signal may be provided to baseband circuitry 204 for further processing. In some embodiments, the output baseband signal may be a zero frequency baseband signal, but this is not required. In some embodiments, mixer circuit 206a of the receive signal path may comprise a passive mixer, although the scope of the embodiments is not limited in this respect. In some embodiments, the mixer circuit 206a of the transmit signal path may be configured to upconvert the input baseband signal based on the synthesized frequency provided by the synthesizer circuit 206d to generate an RF output signal for the FEM circuit 208. The baseband signal may be provided by baseband circuitry 204 and may be filtered by filter circuitry 206c. The filter circuit 206c may include a Low Pass Filter (LPF), although the scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may comprise two or more mixers and may be arranged for quadrature down-conversion and/or up-conversion, respectively. In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a 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 circuit 206a and the mixer circuit 206a of the receive signal path may be arranged for direct down-conversion and/or direct up-conversion, respectively. In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may be configured for superheterodyne operation.

In some embodiments, the output baseband signal and the input baseband signal may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternative embodiments, the output baseband signal and the input baseband signal may be digital baseband signals. In these alternative embodiments, the RF circuitry 206 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry, and the baseband circuitry 204 may include a digital baseband interface to communicate with the RF circuitry 206. In some dual mode embodiments, separate radio IC circuits may be provided to process signals for each spectrum, although the scope of the embodiments is not limited in this respect.

In some embodiments, synthesizer circuit 206d may be a fractional-N synthesizer or a fractional-N/n+1 synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, the synthesizer circuit 206d may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer including a phase locked loop with a frequency divider. The synthesizer circuit 206d may be configured to synthesize an output frequency for use by the mixer circuit 206a of the RF circuit 206 based on the frequency input and the divider control input. In some embodiments, synthesizer circuit 206d may be a fractional N/n+1 synthesizer. In some embodiments, the frequency input may be provided by a Voltage Controlled Oscillator (VCO), but this is not required. The divider control input may be provided by the baseband circuitry 204 or the application processor 202 depending on the desired output frequency. In some embodiments, the divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the application processor 202.

The synthesizer circuit 206d of the RF circuit 206 may include a frequency divider, a Delay Locked Loop (DLL), a multiplexer, and a phase accumulator. In some embodiments, the frequency divider may be a dual-mode frequency divider (DMD) and the phase accumulator may be a Digital Phase Accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by N or n+1 (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, a 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 decompose the VCO period into up to Nd equal phase packets, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuit 206d 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 with quadrature generator and divider circuits to generate a plurality of signals having a plurality of mutually different phases at the carrier frequency. In some embodiments, the output frequency may be the LO frequency (f _LO ). In some embodiments, the RF circuit 206 may include an IQ/polarity converter.

FEM circuitry 208 may include a receive signal path that may include circuitry configured to operate on RF signals received from one or more antennas 210A-D, amplify the received signals, and provide an amplified version of the received signals to RF circuitry 206 for further processing. FEM circuitry 208 may also include a transmit signal path that may include circuitry configured to amplify signals provided by RF circuitry 206 for transmission by one or more of the one or more antennas 210A-D.

In some embodiments, FEM circuitry 208 may include a transmit/receive (TX/RX) switch to switch between transmit 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 the received RF signal and provide the amplified received RF signal as an output (e.g., to the RF circuitry 206). The transmit signal path of FEM circuitry 208 may include a Power Amplifier (PA) for amplifying an input RF signal (e.g., provided by RF circuitry 206) and one or more filters for generating an RF signal for subsequent transmission (e.g., through one or more of one or more antennas 210). In some embodiments, the UE 200 may include additional elements such as memory/storage, a display, a camera, sensors, and/or input/output (I/O) interfaces.

Fig. 3 is a functional diagram of an evolved node B (eNB) in accordance with some embodiments. It should be noted that in some embodiments, the eNB 300 may be a stationary non-mobile device. The eNB 300 may be suitable for use as the eNB 120 as shown in fig. 1. The components of eNB 300 may be included in a single device or multiple devices. The eNB 300 may include physical layer (PHY) circuitry 302 and a transceiver 305, and one or both of the physical layer circuitry 302 and transceiver 305 may allow for the use of one or more antennas 301A-B to transmit signals to and receive signals from the UE 200, other enbs, other UEs, or other devices. For example, the physical layer circuitry 302 may perform various encoding and decoding functions, which may include formatting of baseband signals for transmission and decoding of received signals. For example, physical layer circuitry 302 may include LDPC encoder/decoder functionality, and optionally some other techniques, such as block codes, convolutional codes, turbo codes, etc., which may be used to support legacy protocols. Embodiments of the modem and encoder/decoder functions are not limited to these examples and may include other suitable functions in other embodiments. As another example, transceiver 305 may perform various transmit and receive functions, such as conversion of signals between baseband and Radio Frequency (RF) ranges. Thus, the physical layer circuitry 302 and transceiver 305 may be separate components or may be part of a combined component. Further, some of the functions described in connection with the transmission and reception of signals may be implemented by a combination including one, any, or all of the physical layer circuitry 302, transceiver 305, and other components or layers. The eNB 300 may also include Medium Access Control (MAC) circuitry to control access to the wireless medium. The eNB 300 may also include processing circuitry 306 and memory 308 arranged to perform the operations described herein. The eNB 300 may also include one or more interfaces 310 that may allow for communication with other components, including other enbs 104 (fig. 1), components in the EPC 120 (fig. 1), or other network components. In addition, interface 310 may allow for communication with other components (including components external to the network) that may not be shown in fig. 1. Interface 310 may be wired or wireless or a combination thereof.

Antennas 210A-D (in the UE) and antennas 301A-B (in the eNB) may comprise one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some multiple-input or output (MIMO) embodiments, antennas 210A-D, 301A-B may be effectively separated to take advantage of spatial diversity and the different channel characteristics that may result.

In some embodiments, the UE 200 or eNB 300 may be a mobile device and may be a portable wireless communication device, such as a Personal Digital Assistant (PDA), a laptop or portable computer with wireless communication capability, a netbook, a wireless telephone, a smart phone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a wearable device such as a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), or other device that may receive or transmit information wirelessly. In some embodiments, UE 200 or eNB 300 may be configured to operate in accordance with 3GPP standards, although the scope of the embodiments is not limited in this respect. The mobile device or other devices in some embodiments may be configured to operate in accordance with other protocols or standards, including IEEE 802.11 or other IEEE standards. In some embodiments, the UE 200, eNB 300, or other device may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen.

Although UE 200 and eNB 300 are each shown as having multiple separate functional elements, one or more of these functional elements may be combined and may be implemented by combinations of software-configured elements, e.g., processing elements including Digital Signal Processors (DSPs), or other hardware elements. For example, some elements may include one or more microprocessors, DSPs, field Programmable Gate Arrays (FPGAs), application Specific Integrated Circuits (ASICs), radio Frequency Integrated Circuits (RFICs), and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, a functional element may refer to one or more processes running on one or more processing elements.

Embodiments may be implemented in one or a combination of hardware, firmware, and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, computer-readable storage devices may include read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, and other storage devices and media. Some embodiments may include one or more processors and may be configured with instructions stored on a computer-readable storage device.

It should be noted that in some embodiments, the apparatus used by the UE 200 or eNB 300 may include various components of the UE 200 or eNB 300 as shown in fig. 2 and 3. Accordingly, the techniques and operations described herein relating to UE 200 (or 104) may be applied to an apparatus for a UE. Furthermore, the techniques and operations described herein relating to eNB 300 (or 120) may be applied to an apparatus for an eNB.

Although specific durations (e.g., time interval durations, transmission times, etc.) and specific bit sequence sizes are referred to herein, the disclosure is not limited in this respect and specific sequence numbers are specified for illustrative purposes only.

Fig. 4 illustrates an unlicensed uplink transmission (GUL) according to an example embodiment. Referring to fig. 4, communication 400 may occur in a multewire system, such as between UE 104 and eNB 120. The UE 104 and eNB 120 may communicate over one or more communication bands in an unlicensed spectrum that may be shared with Wi-Fi stations (e.g., access points) 402.

In an example, the UE 104 may be configured to communicate with the scheduled transmission. For example, eNB 120 may transmit a Downlink (DL) burst 404 (e.g., on PUSCH in an unlicensed spectrum). DL burst 404 may include UL grants for scheduled transmissions of the UE. The UE may then perform the scheduled transmission of UL burst 406.

In an example, the UE 104 may perform unlicensed UL transmission (GUL) 410 using PUSCH of an unlicensed spectrum. Prior to performing the GUL, the UE 104 may perform channel contention (e.g., listen before talk or LBT 408) without explicit indication from the eNB 120. The LBT may be a type 4 LBT or a single shot (LBT). After LBT is performed, the UE 104 may send data and/or UL control information via the GUL 410 on PUSCH. The UL control information may include UE identification (UEID) information, a Modulation Coding Scheme (MCS) used by the UE, a Redundancy Version (RV), and/or a New Data Indicator (NDI). In response, eNB 120 may transmit Downlink (DL) control information 412, which may include Acknowledgement (ACK)/Negative Acknowledgement (NACK) for GUL 410, UL Channel State Information (CSI), and/or MCS indication for the UE.

In an example, the eNB may send DL control information 412A as a result of LBT 408, after the GUL 410, and within a time interval reserved for transmission by the UE. In another example, the eNB may send DL control information 412 in a subsequent subframe (e.g., before the scheduled DL burst transmission 414 after performing LBT).

Fig. 4 also shows an eNB DL transmission burst 414 with UL grant and a subsequent UL transmission burst 416 as a result of the grant. The second UE (UE 2) may perform LBT procedure 418 and GUL 420, followed by DL control information transmission 422 by the eNB.

In an example, eNB 120 may be associated with a cell that includes UEs that may perform unlicensed UL transmissions as well as scheduled DL/UL transmissions. One or more techniques described herein may be used to control the impact of unlicensed uplink transmissions on scheduled transmissions.

In an example, eNB 120 may use L1/L2 signaling to control which UEs are allowed to transmit autonomously. More specifically, the eNB 120 may transmit Downlink Control Information (DCI) as L1 signaling or Radio Resource Control (RRC) information as L2 signaling to one or more UEs to indicate whether unlicensed uplink transmission is allowed. For example, L1/L2 signaling may be sent on a common physical downlink control channel (ctpdcch) to all UEs associated with a cell of an eNB. In case the L1/L2 signaling is sent on the ctpdcch or as system information, all UEs are informed whether or not to allow unlicensed uplink transmission. In another example, L1 or L2 signaling may be sent to a particular UE via a Physical Downlink Control Channel (PDCCH) or UE-specific RRC signaling to inform the particular UE whether unlicensed uplink transmissions are allowed. Further, L1 or L2 signaling sent on the PDCCH may be used to inform a group of UEs whether unlicensed uplink transmissions are allowed.

In an example, eNB 120 may control the possible number of UEs based on various indications from the UEs. In the case where the UE has UL data to send, the UE 104 may transmit a Buffer Status Report (BSR) indicating the traffic status at the UE. The eNB 120 may then send L1 or L2 signaling to the UE, allowing BSR-based unlicensed uplink transmission.

In another example, eNB 120 may determine whether the UE requires an unlicensed transmission based on a congestion experience at the UE. In cases where the UE experiences severe congestion at channel access, the eNB may increase UL transmission opportunities by allowing the UE to make unlicensed uplink transmissions. For example, the congestion status may be based on the rate of UL grant failures. More specifically, in the event that the UE cannot send a scheduled PUSCH transmission for a particular number of UL grants, the eNB may signal the UE to perform an unlicensed uplink transmission. In view of this, unlicensed uplink transmission may improve UL contention opportunities. In an example, the eNB may signal the UE to perform an unlicensed uplink transmission after a certain number of failures of the scheduled uplink transmission of the UE.

In an example, the UE may monitor communications on the CPDCCH from the eNB to determine any ongoing or upcoming scheduled DL or UL transmissions. The UE may then defer its unlicensed uplink transmission to avoid coexistence with the scheduled transmission.

Fig. 5 illustrates an example unlicensed UL transmission (GUL) within a restricted timing window in accordance with an example embodiment. Referring to fig. 5, communications 500 illustrate how an eNB may limit operation of unscheduled communications (e.g., unlicensed uplink transmissions) to a particular known period of time. More specifically, the eNB may inform the UE of a repetition Discovery Reference Signal (DRS) transmission window (DTxW) period 502A of a DTxW 504. DTxW 504 may be a time interval for transmitting a DRS (e.g., DRS 508). In an example, paging signal 510 may also be sent based on an eNB-initiated paging occasion. The DRS 508 may include, for example, a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), system information transmitted over a Physical Broadcast Channel (PBCH), and a cell-specific reference signal (CRS). The eNB may inform the UE of the allowed unlicensed transmission interval 506A, which is outside of the restricted DTxW 504 (e.g., 504A). In another example, the eNB may indicate available time domain resources, e.g., in the form of a set of subframes available for the GULs. RRC signaling may be used for such indication. The set of subframes available for GUL may be indicated by an N-bit bitmap, and the pattern may repeat every N milliseconds (ms). In one example, n=40.

As shown in fig. 5, the scheduled downlink and uplink transmissions 512 and the unlicensed uplink transmission 514 may occur within the allowed unlicensed transmission interval 506A. Similarly, the eNB may transmit the DRS 516 and a portion of the scheduled downlink transmission 518 during the DTxW 504B within the DTxW period 502B. The unlicensed uplink transmission 520 may be performed outside of the DTxW 504B. In view of this, by restricting unlicensed uplink transmissions to time intervals other than DTxW, the eNB may minimize the impact of unlicensed uplink transmissions on critical downlink transmissions (e.g., DRS transmissions).

In an example, the maximum duration of the unlicensed UL transmission may be limited. For example, the eNB may indicate to the UE that the maximum duration for unlicensed UL transmission is 4ms, and the UE may transmit within a 4ms interval after which the UE needs to re-contend for the channel (and perform LBT).

In an example, the eNB and/or UE may perceive availability (or absence) of Wi-Fi stations and may activate or deactivate unlicensed UL transmissions based on such availability. For example, the eNB may deactivate unlicensed UL transmissions in the absence of Wi-Fi stations within the unlicensed spectrum within the eNB cell.

Fig. 6A and 6B illustrate example Downlink (DL) transmissions after unlicensed UL transmissions according to example embodiments.

In a communication environment where scheduled transmissions from enbs and Wi-Fi stations predominate, performance of unlicensed UL transmissions may be poor because there is less opportunity to transmit HARQ ACK/NACK feedback, UL CSI, and/or MCS information from the enbs in response to the unlicensed UL transmissions. To increase the transmission opportunity of DL control information, the DL control information may follow the GUL and after the eNB performs a single interval LBT. In an example, if DL control information is within a Maximum Channel Occupancy Time (MCOT) initialized by a UE associated with an eNB, the eNB does not perform LBT for the DL control information. For example and with reference to communication 600A in fig. 6A, unlicensed uplink transmission 606A may occur before unlicensed uplink transmission 608A. Downlink control information 610A including ACK/NACK, UL CSI, and/or MCS in response to the unlicensed uplink transmission 606A may occur after the unlicensed uplink transmission 608A. Further, the downlink control information 614A in response to the unlicensed uplink transmission 608A may pass through a delay 620A and may be transmitted after the unlicensed uplink transmission 612A. Similarly, downlink control information 616A in response to unlicensed uplink transmission 612A may pass through delay 622A and may be transmitted after scheduled (or Wi-Fi) transmission, as shown in fig. 6A. In the case where DL control information (e.g., 616A in fig. 6A) is transmitted outside the TxOP, type 4 LBT is performed for DL control information transmission.

Referring to communication 600B in fig. 6B, unlicensed uplink transmission 602B may occur before unlicensed uplink transmission 604B. Downlink control information 606B including ACK/NACK, UL CSI, and/or MCS in response to the unlicensed uplink transmission 602B may occur after the unlicensed uplink transmission 604B. Further, the downlink control information 610B in response to the unlicensed uplink transmission 604B may be delayed and may be transmitted after the unlicensed uplink transmission 608B. Similarly, downlink control information 614B in response to the unlicensed uplink transmission 608B may be delayed and may be transmitted during the scheduled DL burst 612B. In these examples, DL control information 606B and 610B may perform a single interval LBT if within the MCOT initialized by the UE transmitting 602B/604B/608B GUL, or may not perform LBT if within, for example, 16us from the end of the previous UL transmission and within the MCOT initialized by the UE with GUL transmission. In the example of DL control information 614B, since the eNB has performed LBT of type 4 for DL burst 612B, no LBT or single interval LBT is performed to transmit DL control information 614B. In the case where DL control information (e.g., 614B) is transmitted outside of a transmission opportunity (TxOP), type 4 LBT is performed for DL control information transmission.

In an example, to reduce the delay in receiving DL control information from an eNB, a UE may autonomously perform an LBT procedure (e.g., type 4 LBT) to request feedback for a pending HARQ process (e.g., unacknowledged unlicensed UL transmission). In addition to type 4 LBT contention of the eNB, the contention may be used to transmit ACK/NACK feedback. Immediately after the UE performs an unlicensed UL transmission requesting DL control information, the eNB may transmit HARQ ACK/NACK with a very short LBT procedure (or without LBT procedure), as shown by communication 600C in fig. 6C.

Fig. 6C illustrates an example Downlink (DL) transmission after requesting an acknowledged unlicensed UL transmission, according to an example embodiment.

Referring to communication 600C in fig. 6C, unlicensed uplink transmission 608C may occur before unlicensed uplink transmission 610C. Downlink control information 612C including ACK/NACK, UL CSI, and/or MCS in response to the unlicensed uplink transmission 608 may occur after the unlicensed uplink transmission 610C. Further, the downlink control information 616C in response to the unlicensed uplink transmission 610C may be delayed and may be transmitted after the unlicensed uplink transmission 614C. Similarly, downlink control information responsive to unlicensed uplink transmission 614C may pass through delay 626C and may be transmitted after scheduled transmissions 618C and 624C. In an example, to reduce the delay in receiving downlink control information in response to unlicensed uplink transmission 614C, the UE may perform LBT and unlicensed UL transmission 620C requesting DL control information (including ACK/NACK, UL CSI, and/or MCS in response to unlicensed uplink transmission 614C). Then, after the unlicensed UL transmission 620C, DL control information 622C is transmitted in response to the unlicensed uplink transmission 614C.

Fig. 7 and 8 are flowcharts illustrating example functions for performing unlicensed uplink transmissions, in accordance with some embodiments. Referring to fig. 7, an example method 700 may begin at 702, at which time control information received on one or more channels of an unlicensed spectrum may be decoded. The control information may include an indicator that unlicensed Uplink (UL) transmissions are allowed without prior UL grants. For example, eNB 120 may use physical layer (i.e., L1) signaling or higher layer signaling (e.g., DCI or RRC signaling) to indicate to the UE that unlicensed UL transmissions are allowed within a particular resource. At 704, a Listen Before Talk (LBT) procedure is performed on one or more channels of the unlicensed spectrum to determine whether there is one available channel in the unlicensed spectrum channels. For example, the UE 104 may perform the LBT procedure 408. At 706, upon determining that a channel is available, UL control information and data may be encoded for transmission on a Physical Uplink Shared Channel (PUSCH), a short physical uplink control channel (sPUCCH), and/or an extended PUCCH (ePUCCH) using unlicensed UL transmissions. For example, the GUL 410 may be performed by the UE without prior UL grant by the eNB. In view of this, unlicensed uplink transmission 410 is an unscheduled unlicensed transmission performed on an available channel of the unlicensed spectrum without UL grant.

Referring to fig. 8, an example method 800 may begin at 802 when control information may be encoded for transmission on one or more channels of an unlicensed spectrum. For example, eNB 120 may encode physical layer or higher layer signaling (e.g., DCI or RRC signaling) that may include an indication that unlicensed Uplink (UL) transmissions are allowed without prior UL grant within a particular resource. At 804, UL control information and data may be decoded. Control information and data may be received on a sPUCCH/ePUCCH and/or a Physical Uplink Shared Channel (PUSCH) using unlicensed UL transmissions. For example, control information and data may be received from a UE via an unlicensed uplink transmission, where the unlicensed uplink transmission is an unscheduled unlicensed transmission performed on one or more channels of an unlicensed spectrum without UL grant. At 806, acknowledgement (ACK) feedback or Negative Acknowledgement (NACK) feedback may be encoded in response to the unlicensed uplink transmission. For example, the eNB may encode DL control information 412A for transmission to the UE, including ACK/NACK indications, UL CSI, and/or MCS information.

Fig. 9 illustrates a block diagram of a communication device (e.g., an eNB or UE) in accordance with some embodiments. In alternative embodiments, communication device 900 may operate as a standalone device or may be connected (e.g., networked) to other communication devices. In a networked deployment, the communication device 900 may operate in the capacity of a server communication device, a client communication device, or both, in a server-client network environment. In an example, the communication device 900 may be used as a peer-to-peer communication device in a peer-to-peer (P2P) (or other distributed) network environment. The communication device 900 may be UE, eNB, PC, a tablet PC, STB, PDA, a mobile phone, a smart phone, a network appliance, a network router, switch or bridge, or any communication device capable of executing instructions (sequentially or otherwise) specifying actions to be taken by the communication device. Furthermore, while only a single communication device is illustrated, the term "communication device" shall also be taken to include any collection of communication devices that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein, such as cloud computing, software as a service (SaaS), or other computer cluster configurations.

Examples as described herein may include, or may operate on, logic or multiple components, modules, or mechanisms. A module is a tangible entity (e.g., hardware) capable of performing specified operations and may be configured or arranged in a particular manner. In an example, the circuits may be arranged (e.g., internally or with respect to external entities such as other circuits) as modules in a specified manner. In an example, all or a portion of one or more computer systems (e.g., stand-alone, client or server computer systems) or one or more hardware processors may be configured by firmware or software (e.g., instructions, application portions or applications) as modules that operate to perform specified operations. In an example, the software may reside on a communication device readable medium. In an example, the software, when executed by the underlying hardware of the module, causes the hardware to perform specified operations.

Thus, the term "module" is understood to include tangible entities, i.e., entities that are physically constructed, specifically configured (e.g., hardwired) or temporarily (e.g., programmed) to operate in a specified manner or to perform some or all of any of the operations described herein. Considering the example where modules are temporarily configured, each module need not be instantiated at any time. For example, where a module includes a general-purpose hardware processor configured using software, the general-purpose hardware processor may be configured as corresponding different modules at different times. The software may configure the hardware processor accordingly, for example, to constitute a particular module at one time and another module at another time.

The communication device (e.g., UE) 900 may include a hardware processor 902 (e.g., a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), a hardware processor core, or any combination thereof), a main memory 904, and a static memory 906, some or all of which may communicate with each other via an interconnect (e.g., bus) 908. The communication device 900 may also include a display unit 910, an alphanumeric input device 912 (e.g., a keyboard), and a User Interface (UI) navigation device 914 (e.g., a mouse). In an example, the display unit 910, the input device 912, and the UI navigation device 914 may be touch screen displays. The communication device 900 may also include a storage device (i.e., a drive unit) 916, a signal generation device 918 (e.g., a speaker), a network interface device 920, and one or more sensors 921 (e.g., a Global Positioning System (GPS) sensor, compass, accelerometer, or other sensor). The communication device 900 may include an output controller 928, such as a serial (e.g., universal Serial Bus (USB)), parallel, or other wired or wireless (e.g., infrared (IR), near Field Communication (NFC), etc.) connection to communicate with or control one or more peripheral devices (e.g., printer, card reader, etc.).

The storage 916 may include a communication device-readable medium 922 on which is stored one or more sets of data structures or instructions (e.g., software) 924 embodied or used by any one or more of the techniques or functions described herein. The instructions 924 may also reside, partially or completely, within the main memory 904, within the static memory 906, or within the hardware processor 902 during execution thereof by the communication device 900. In an example, one or any combination of the hardware processor 902, the main memory 904, the static memory 906, or the storage device 916 may constitute communication device readable media.

While the communication device-readable medium 922 is shown to be a single medium, the term "communication device-readable medium" may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instructions 924.

The term "communication device readable medium" can include any medium that can store, encode, or carry instructions for execution by communication device 900 and that cause communication device 900 to perform any one or more of the techniques of this disclosure, or that can store, encode, or carry data structures used by or associated with such instructions. Non-limiting examples of communication device readable media may include solid state memory, and optical and magnetic media. Specific examples of a communication device readable medium may include non-volatile memory such as semiconductor memory devices (e.g., electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disk; random Access Memory (RAM); CD-ROM and DVD-ROM discs. In some examples, the communication device readable medium may include a non-transitory communication device readable medium. In some examples, the communication device readable medium may include a communication device readable medium that is not a transitory propagating signal.

The instructions 924 may also be transmitted or received over a communications network 926 that uses a transmission medium via a network using multiple transmission protocols (e.g., frame relay, internet Protocol (IP), transmission Control Protocol (TCP), user Datagram Protocol (UDP), hypertext transfer protocol (HTTP), etc.)A network interface device 920. Example communication networks may include a Local Area Network (LAN), a Wide Area Network (WAN), a packet data network (e.g., the internet), a mobile telephone network (e.g., a cellular network), a Plain Old Telephone (POTS) network, a wireless data network (e.g., known asIs known as +.o.A Institute of Electrical and Electronics Engineers (IEEE) 802.11 family standard>The IEEE 802.16 series of standards), the IEEE 802.15.4 series of standards, the Long Term Evolution (LTE) series of standards, the Universal Mobile Telecommunications System (UMTS) series of standards, peer-to-peer (P2P) networks, and so forth. In an example, the network interface device 920 may include one or more physical jacks (e.g., ethernet, coaxial, or telephone jacks) or one or more antennas to connect to the communications network 926. In an example, the network interface device 920 may include multiple antennas to wirelessly communicate using at least one of single-input multiple-output (SIMO), multiple-input multiple-output (MIMO), or multiple-input single-output (MISO) technologies. In some examples, network interface device 920 may communicate wirelessly using multi-user MIMO technology. The term "transmission medium" shall be taken to include any intangible medium that is capable of storing, encoding, or carrying instructions for execution by the communication device 900, and includes digital or analog communication signals or other intangible medium to facilitate communication of such software.

Additional description and examples:

example 1 is an apparatus of a User Equipment (UE), the apparatus comprising: a memory; and processing circuitry configured to: decoding control information received on one or more channels of an unlicensed spectrum, the control information including an indication that unlicensed Uplink (UL) transmissions (GULs) are allowed without prior UL grants; performing a Listen Before Talk (LBT) procedure on one or more channels of the unlicensed spectrum to determine whether there is one available channel in the channels; and when it is determined that the channel is available, encoding UL control information and data for transmission using an unlicensed UL transmission, wherein the unlicensed uplink transmission is an unscheduled transmission performed on a channel of an unlicensed spectrum without UL grant.

In example 2, the subject matter of example 1 optionally includes: wherein the control information is Downlink Control Information (DCI) received on a common physical downlink control channel (ctpdcch) within an unlicensed spectrum.

In example 3, the subject matter of any one or more of examples 1-2 optionally includes: wherein the memory stores UL control information and data for transmission using the unlicensed UL transmission.

In example 4, the subject matter of any one or more of examples 1-3 optionally includes: wherein the control information is Radio Resource Control (RRC) information received on a Physical Downlink Shared Channel (PDSCH) within the unlicensed spectrum.

In example 5, the subject matter of any one or more of examples 1-4 optionally includes: wherein the UL control information includes at least one of: UE identity (UE id) of the UE; a Modulation Coding Scheme (MCS) used by the UE; redundancy Versions (RVs) for the UE for data transmission; a New Data Indicator (NDI) associated with the data transmission; a length of an UL burst transmitting UL control information; and a Maximum Channel Occupation Time (MCOT) reserved by the performed LBT.

In example 6, the subject matter of any one or more of examples 1-5 optionally includes: wherein the processing circuit is configured to: a Buffer Status Report (BSR) is encoded for transmission to an evolved node B (eNB), the BSR indicating transmission congestion of a scheduled UL transmission of the UE.

In example 7, the subject matter of example 6 optionally includes: wherein control information including an indicator allowing unlicensed UL transmissions is received in response to the BSR.

In example 8, the subject matter of any one or more of examples 1-7 optionally includes: wherein the processing circuit is configured to: monitoring a common physical downlink control channel (cppdcch) within an unlicensed spectrum for scheduled transmissions; and detecting the presence of burst information of a scheduled Downlink (DL) transmission and/or a scheduled UL transmission in an unlicensed spectrum by an evolved node B (eNB) indicated by the ctpdcch.

In example 9, the subject matter of example 8 optionally includes: wherein the processing circuit is configured to: unlicensed uplink transmissions are deferred to avoid coexistence with scheduled DL transmissions and/or scheduled UL transmissions.

In example 10, the subject matter of any one or more of examples 1-9 optionally includes: wherein the processing circuit is configured to: second Downlink (DL) control information received on one or more channels of an unlicensed spectrum is decoded, the second DL control information including Acknowledgement (ACK)/Negative Acknowledgement (NACK) signaling in response to an unlicensed uplink transmission.

In example 11, the subject matter of any one or more of examples 9-10 optionally includes: wherein the second control information is received during a Maximum Channel Occupancy Time (MCOT) reserved by the UE during the LBT procedure.

In example 12, the subject matter of any one or more of examples 1-11 optionally includes: wherein the processing circuit is configured to: decoding signaling indicating periodicity of DRS transmissions within DTxW; and limiting the unlicensed UL transmissions to time intervals other than DTxW.

In example 13, the subject matter of any one or more of examples 1-12 optionally includes: wherein the processing circuit is configured to: an indication of available time domain resources available for unlicensed UL transmissions is decoded.

In example 14, the subject matter of any one or more of examples 1-13 optionally includes: wherein the available time domain resources comprise a set of available subframes, and wherein the indication is an N-bit bitmap, the pattern of N bits repeating every N ms.

In example 15, the subject matter of any one or more of examples 1-14 optionally includes: wherein the control information comprises an indication of a maximum UL transmission duration and the processing circuitry is configured to: the duration of the unlicensed UL transmission is limited to be within the maximum UL transmission duration.

Example 16 is an apparatus of an evolved node B (eNB), comprising: a memory; and processing circuitry configured to: encoding control information for transmission on one or more channels of an unlicensed spectrum, the control information including an indication that unlicensed Uplink (UL) transmission is allowed without a prior UL grant; decoding UL control information and data received using an unlicensed UL transmission, wherein the unlicensed uplink transmission is an unscheduled transmission performed on one or more channels of an unlicensed spectrum; and encoding Acknowledgement (ACK) feedback or Negative Acknowledgement (NACK) feedback in response to the unlicensed uplink transmission.

In example 17, the subject matter of example 16 optionally includes: wherein the processing circuit is configured to: encoding an UL grant for transmission to the UE, the UL grant being associated with the scheduled UL transmission; and detecting a number of failures of the scheduled UL transmission.

In example 18, the subject matter of any one or more of examples 16-17 optionally includes: wherein the memory stores control information for transmission over one or more channels of the unlicensed spectrum.

In example 19, the subject matter of any one or more of examples 17-18 optionally includes: wherein the processing circuit is configured to: control information is encoded, the control information indicating that unlicensed UL transmissions are allowed in response to a detected number of failures of scheduled UL transmissions.

In example 20, the subject matter of any one or more of examples 16-19 optionally includes: wherein to encode the control information, the processing circuit is configured to: downlink Control Information (DCI) is encoded, the downlink control information including an indicator that unlicensed UL transmissions are allowed to be transmitted on a common physical downlink control channel (ctpdcch) within an unlicensed spectrum.

In example 21, the subject matter of any one or more of examples 16-20 optionally includes: wherein to encode the control information, the processing circuit is configured to: radio Resource Control (RRC) information is encoded, the RRC information including an indicator that unlicensed UL transmissions are allowed to be transmitted on a Physical Downlink Shared Channel (PDSCH) within an unlicensed spectrum.

In example 22, the subject matter of any one or more of examples 16-21 optionally includes: wherein the processing circuit is configured to: a Buffer Status Report (BSR) from a User Equipment (UE) is decoded, the BSR indicating transmission congestion of a scheduled UL transmission of the UE.

In example 23, the subject matter of example 22 optionally includes: wherein the processing circuit is configured to: control information is encoded with an indication that unlicensed UL transmissions are allowed to be transmitted on one or more channels of an unlicensed spectrum in response to the BSR.

In example 24, the subject matter of any one or more of examples 22-23 optionally includes: wherein the processing circuit is configured to: a second unlicensed UL transmission is decoded, the second unlicensed UL transmission comprising a request for acknowledgement of the unlicensed UL transmission.

In example 25, the subject matter of example 24 optionally includes: wherein the processing circuit is configured to: in response to the second unlicensed UL transmission, second Acknowledgement (ACK)/Negative Acknowledgement (NACK) feedback in response to the unlicensed uplink transmission is encoded.

Example 26 is a computer-readable storage medium storing instructions for execution by one or more processors of a User Equipment (UE) to configure the UE to: decoding an indication of a Discovery Reference Signal (DRS) transmission window (DTxW) period, the DTxW period indicating a periodicity of DRS transmissions within the DTxW; decoding control information received on one or more channels of an unlicensed spectrum, the control information including an indication that unlicensed Uplink (UL) transmissions are allowed without prior UL grants; performing a Listen Before Talk (LBT) procedure on one or more channels of an unlicensed spectrum; and transmitting the encoded UL control information and data on a Physical Uplink Shared Channel (PUSCH), a short physical uplink control channel (sPUCCH), and/or an extended PUCCH (ePUCCH) of the unlicensed spectrum using an unlicensed UL transmission, wherein the unlicensed uplink transmission is performed without UL grant within a time interval other than DTxW.

In example 27, the subject matter of example 26 optionally includes: wherein the one or more processors further configure the UE to: monitoring a common physical downlink control channel (cppdcch) within an unlicensed spectrum for scheduled transmissions; and detecting the presence of burst information of a scheduled Downlink (DL) transmission and/or a scheduled UL transmission in an unlicensed spectrum by an evolved node B (eNB) indicated by the ctpdcch.

In example 28, the subject matter of example 27 optionally includes: wherein the one or more processors further configure the UE to: unlicensed uplink transmissions are deferred to avoid coexistence with scheduled DL transmissions and/or scheduled UL transmissions scheduled by an associated eNB.

In example 29, the subject matter of any one or more of examples 27-28 optionally includes: wherein the one or more processors further configure the UE to: second control information is received on one or more channels of the unlicensed spectrum, the second control information including Acknowledgement (ACK)/Negative Acknowledgement (NACK) feedback in response to the unlicensed uplink transmission.

In example 30, the subject matter of example 29 optionally includes: wherein the second control information is received during a Maximum Channel Occupancy Time (MCOT) reserved by the UE during the LBT procedure.

In example 31, the subject matter of any one or more of examples 26-30 optionally includes: wherein the one or more processors further configure the UE to: failure to receive first Acknowledgement (ACK)/Negative Acknowledgement (NACK) signaling in response to an unlicensed uplink transmission is detected.

In example 32, the subject matter of example 31 optionally includes: wherein the one or more processors further configure the UE to: responsive to detecting the failure, encoding a request for acknowledgement of the unlicensed UL transmission; a request for acknowledgement is sent using a second unlicensed UL transmission.

In example 33, the subject matter of example 32 optionally includes: wherein the processing circuit is configured to: a second Acknowledgement (ACK)/Negative Acknowledgement (NACK) feedback associated with the unlicensed uplink transmission is decoded, the second ACK/NACK signaling received in response to the second unlicensed UL transmission.

Example 34 is an apparatus of a User Equipment (UE), the apparatus comprising means for decoding an indication of a Discovery Reference Signal (DRS) transmission window (DTxW) period, the DTxW period indicating a periodicity of DRS transmissions within the DTxW; means for decoding control information received on one or more channels of an unlicensed spectrum, the control information including an indication that unlicensed Uplink (UL) transmissions are allowed without a prior UL grant; means for performing a Listen Before Talk (LBT) procedure on one or more channels of an unlicensed spectrum; and transmitting the encoded UL control information and data on a Physical Uplink Shared Channel (PUSCH), a short physical uplink control channel (sPUCCH), and/or an extended PUCCH (ePUCCH) of the unlicensed spectrum using an unlicensed UL transmission, wherein the unlicensed uplink transmission is performed without UL grant for a time interval other than DTxW.

In example 35, the subject matter of example 34 optionally includes: means for monitoring a common physical downlink control channel (ctpdcch) within an unlicensed spectrum for scheduled transmissions; and means for detecting the presence of burst information of a scheduled Downlink (DL) transmission and/or a scheduled UL transmission in an unlicensed spectrum by an evolved node B (eNB) indicated by the ctpdcch.

In example 36, the subject matter of example 35 optionally includes: means for deferring unlicensed uplink transmissions to avoid coexistence with scheduled DL transmissions and/or scheduled UL transmissions scheduled by an associated eNB.

In example 37, the subject matter of any one or more of examples 35-36 optionally includes: means for receiving second control information on one or more channels of the unlicensed spectrum, the second control information including Acknowledgement (ACK)/Negative Acknowledgement (NACK) feedback in response to the unlicensed uplink transmission.

In example 38, the subject matter of example 37 optionally includes: wherein the second control information is received during a Maximum Channel Occupancy Time (MCOT) reserved by the UE during the LBT procedure.

In example 39, the subject matter of any one or more of examples 34-38 optionally includes: means for detecting a failure to receive a first Acknowledgement (ACK)/Negative Acknowledgement (NACK) signaling in response to an unlicensed uplink transmission.

In example 40, the subject matter of example 39 optionally includes: means for encoding a request for acknowledgement of an unlicensed UL transmission in response to detecting the failure; means for transmitting a request for acknowledgement using a second unlicensed UL transmission.

In example 41, the subject matter of example 40 optionally includes: means for decoding a second Acknowledgement (ACK)/Negative Acknowledgement (NACK) feedback associated with the unlicensed uplink transmission, the second ACK/NACK signaling received in response to the second unlicensed UL transmission.

Publications, patents, and patent documents referred to in this document are incorporated by reference in their entirety as if individually incorporated by reference. In the event there is inconsistent usage between the present document and those documents incorporated by reference, the usage in the incorporated reference(s) is complementary to the usage in the present document; for inconsistencies that are completely incompatible, the usage in this document is followed.

The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (and one or more aspects thereof) may be used in conjunction with other examples. For example, other embodiments may be used by those skilled in the art after reviewing the above description. The abstract is provided to enable the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Furthermore, in the detailed description section above, various features may be combined together to make up the present disclosure. However, the claims may not reveal every feature disclosed herein, as embodiments may embody a subset of the features. Further, embodiments may include fewer features than those disclosed in the specific examples. Thus the following claims are hereby incorporated into the detailed description, with the claims themselves being separate embodiments. The scope of the embodiments disclosed herein is to be determined with reference to the appended claims, along with the full range of equivalents to which such claims are entitled.

Claims (20)

1. A method, comprising:

the base station BS:

transmitting control information for transmission on one or more channels of an unlicensed spectrum, the control information including an indication that autonomous UL transmission is allowed without a prior uplink UL grant; and

receiving UL control information and data, the UL control information and the data being received using the autonomous UL transmission, wherein the autonomous UL transmission is an unscheduled transmission performed on the one or more channels of the unlicensed spectrum without UL grant; and

and transmitting acknowledgement, ACK, feedback or negative acknowledgement, NACK, feedback in response to the autonomous UL transmission.

2. The method of claim 1, further comprising:

encoding the UL grant for transmission to a user equipment, UE, the UL grant being associated with a scheduled UL transmission; and

and detecting the number of times of the scheduled UL transmission failure.

3. The method of claim 1, wherein the control information is downlink control information, DCI, transmitted on a common physical downlink control channel, ctpdcch, within the unlicensed spectrum.

4. The method of claim 1, wherein the control information is radio resource control, RRC, information transmitted on a physical downlink shared channel, PDSCH, within the unlicensed spectrum.

5. The method of claim 1, wherein the UL control information comprises at least one of:

UE identity, UE id, of a user equipment UE;

a Modulation and Coding Scheme (MCS) used by the UE;

the redundancy version RV of the UE for data transmission;

a new data indicator NDI associated with the data transmission;

a length of an UL burst transmitting the UL control information; and

the maximum channel occupation time MCOT reserved by the corresponding listen before talk LBT procedure performed by the UE.

6. The method of claim 5, wherein the LBT procedure is performed on the one or more channels to determine whether there is one available channel in the one or more channels.

7. The method of claim 1, further comprising:

a status report, BSR, received from a user equipment, UE, is decoded, wherein the BSR indicates transmission congestion of scheduled UL transmissions of the UE.

8. The method of claim 7, wherein the control information including the indication that the autonomous UL transmission is allowed is transmitted in response to the BSR.

9. The method of claim 1, further comprising:

second downlink DL control information transmitted on the one or more channels of the unlicensed spectrum is encoded, the second DL control information comprising acknowledgement ACK/negative acknowledgement, NACK, signaling in response to the autonomous uplink transmission.

10. The method of claim 9, wherein the second DL control information is transmitted during a listen before talk, LBT, procedure performed by a user equipment, UE, during a maximum channel occupancy time, MCOT, reserved by the UE.

11. The method of claim 1, further comprising:

encoding signaling indicating periodicity of Discovery Reference Signal (DRS) DRS transmissions within a discovery reference signal DRS transmission window DTxW; and

limiting the autonomous UL transmissions to time intervals other than the DTxW.

12. The method of claim 1, further comprising:

an indication of available time domain resources for autonomous UL transmissions is encoded.

13. The method of claim 12, wherein the available time domain resources comprise a set of available subframes, and wherein the indication is an N-bit bitmap that repeats every N milliseconds.

14. A method, comprising:

by the user equipment UE:

receiving control information on one or more channels of an unlicensed spectrum, the control information including an indication that autonomous UL transmissions are allowed without prior uplink UL grants;

performing a listen before talk, LBT, procedure on the one or more channels of the unlicensed spectrum to determine whether there is one available channel in the one or more channels; and

Transmitting UL control information and data for transmission using the unlicensed UL transmission when the channel is determined to be available, wherein the unlicensed uplink transmission is an unscheduled transmission performed on the channel of the unlicensed spectrum without UL grant.

15. The method of claim 14, wherein the control information is downlink control information, DCI, transmitted on a common physical downlink control channel, ctpdcch, within the unlicensed spectrum.

16. The method of claim 14, wherein the control information is radio resource control, RRC, information transmitted on a physical downlink shared channel, PDSCH, within the unlicensed spectrum.

17. The method of claim 14, wherein the UL control information comprises at least one of:

a UE identity, UE id, of the UE;

a Modulation and Coding Scheme (MCS) used by the UE;

the redundancy version RV of the UE for data transmission;

a new data indicator NDI associated with the data transmission;

a length of an UL burst transmitting the UL control information; and

the maximum channel occupation time MCOT reserved by the performed LBT procedure.

18. The method of claim 14, further comprising:

A buffer status report, BSR, is encoded for transmission to a base station, BS, the BSR indicating transmission congestion of scheduled UL transmissions of the UE.

19. An apparatus, comprising:

one or more processors; and

a memory having instructions stored thereon, which when executed by the one or more processors, perform the steps of the method according to any of claims 1-18.

20. A computer-readable storage medium, having stored thereon a computer program product, which, when executed by one or more processors, performs the steps of the method according to any of claims 1-18.