Method and procedure for channel measurement and reporting mechanism for LTE operation

Abstract

Disclosed herein is a method and process for a channel measurement and reporting mechanism for LTE operation, and specifically relates to a method and apparatus for a channel measurement and reporting mechanism for long term evolution (LTE) operation in an unlicensed band implemented in a wireless transmit / receive unit (WTRU). The method comprises the step that the WTRU can communicate with a primary cell working in an authorized frequency band and a secondary cell working in an unauthorized frequency band. The WTRU may receive a request for measurement and reporting in a downlink control information (DCI) signal, wherein the request may indicate at least one time / frequency resource in at least one subframe for performing measurement in an unlicensed band. The WTRU may then perform a measurement in accordance with the request, and may send a measurement report based on the performed measurement. In one example, the indicated at least one time / frequency resource may be a set of physical resource blocks (PRBs) or resource elements (REs).

Description

This application is a divisional application of Chinese Patent Application No. 202010669085.8, whose filing date is November 13, 2015, and entitled “Methods and Processes for Channel Measurement and Reporting Mechanisms for Long Term Evolution (LTE) Operations in Unlicensed Bands”, which is a divisional application of Chinese Patent Application No. 201580072949.5, whose filing date is November 13, 2015, and entitled “Methods and Processes for Channel Measurement and Reporting Mechanisms for Long Term Evolution (LTE) Operations in Unlicensed Bands”. CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 62 / 080,004, filed November 14, 2014, and U.S. Provisional Application No. 62 / 204,274, filed August 12, 2015, the contents of which are hereby incorporated herein by reference. Background Art

[0002] Cellular operators may consider using unlicensed frequency bands traditionally used for non-cellular services and applications (eg, WiFi) as an aid to enhance their service offerings in order to meet the growing high demand for broadband data. Summary of the invention

[0003] Disclosed herein is a method and apparatus for implementing a channel measurement and reporting mechanism for long term evolution (LTE) operation in an unlicensed band in a wireless transmit / receive unit (WTRU). The method includes: the WTRU may communicate with a primary cell operating in a licensed band and a secondary cell operating in an unlicensed band. The WTRU may receive a request for measurement and reporting in a downlink control information (DCI) signal, wherein the request may indicate at least one time / frequency resource in at least one subframe for performing measurements in the unlicensed band. The WTRU may then perform measurements in accordance with the request and may send a measurement report based on the measurements performed.

[0004] In one example, the at least one time / frequency resource indicated may be a set of physical resource blocks (PRBs) or resource elements (REs). In another example, the at least one time / frequency resource indicated may correspond to a set of REs, wherein the set of REs may include REs for one or more of the following: channel state information reference signal (CSI-RS), CSI-interference measurement (IM), zero-power CSI-RS, or cell-specific reference signal (CRS).

[0005] In a further example, the at least one subframe used to perform the measurement may be a subframe related to the request or a window of subframes starting with a subframe related to the request. In another example, the measurement report may be a subframe identifier or a system frame number (SFN) associated with the measurement.

[0006] In another example, the method includes receiving an indication from an evolved Node B (eNodeB), wherein the indication indicates time and frequency resources for performing measurements, performing measurements on the indicated time and frequency resources, and reporting the measurement results to the eNodeB. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] A more detailed understanding may be obtained from the following description given by way of example in conjunction with the accompanying drawings, in which:

[0008] Figure 1A is a system diagram of an example communication system in which one or more disclosed embodiments may be implemented;

[0009] Figure 1B Yes, you can Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) used within the communication system shown;

[0010] Figure 1C Yes, you can Figure 1A A system diagram of an example radio access network and an example core network used within the communication system shown;

[0011] Figure 2 is a system diagram of an illustrative License Assisted Access (LAA) scenario;

[0012] Figure 3 is a system diagram of an example LAA system using listen before talk (LBT);

[0013] Figure 4 is a signal diagram of an example method of a channel measurement and reporting mechanism for Long Term Evolution (LTE) operation in an unlicensed band;

[0014] Figure 5 is a system diagram of an example of a wireless system including hidden nodes; and

[0015] Figure 6 is a signal diagram of another exemplary method of a channel measurement and reporting mechanism for LTE operation in an unlicensed band. DETAILED DESCRIPTION

[0016] Figure 1A1 is a diagram of an exemplary communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system 100 may allow multiple wireless users to access these contents by sharing system resources including wireless bandwidth. As an example, the communication system 100 may use one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or single carrier FDMA (SC-FDMA), etc.

[0017] like Figure 1A As shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network 106, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, although it should be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network components. Each WTRU 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. For example, the WTRUs 102a, 102b, 102c, 102d may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile stations, fixed or mobile subscriber units, pagers, cellular phones, personal digital assistants (PDAs), smart phones, laptops, netbooks, personal computers, wireless sensors, and consumer electronic devices, among others.

[0018] The communication system 100 may also include a base station 114a and a base station 114b. Each base station 114a, 114b may be any type of device configured to facilitate access to one or more communication networks, such as the core network 106, the Internet 110, and / or other networks 112, by wirelessly interfacing with at least one WTRU 102a, 102b, 102c, 102d. The base stations 114a, 114b may be, by way of example, a base transceiver station (BTS), a Node B, an eNode B, a Home Node B, a Home eNode B, a site controller, an access point (AP), a wireless router, or the like. Although each base station 114a, 114b is depicted as a single component, it should be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network components.

[0019] The base station 114a may be part of the RAN 104, which may also include other base stations and / or network components (not shown), such as a base station controller (BSC), a radio network controller (RNC), or a relay node, etc. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals within a specific geographic area called a cell (not shown). The cell may be further divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, that is, each transceiver corresponds to a sector of the cell. In another embodiment, the base station 114a may use multiple-input multiple-output (MIMO) technology, and thus multiple transceivers may be used for each sector in the cell.

[0020] The base stations 114a, 114b may communicate with one or more WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), or visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0021] More specifically, as described above, the communication system 100 may be a multiple access system and may use one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, or SC-FDMA, among others. As an example, the base station 114a in the RAN 104 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may use Wideband CDMA (WCDMA) to establish the air interface 116. WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink Packet Access (HSDPA) and / or High Speed ​​Uplink Packet Access (HSUPA).

[0022] In another embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A).

[0023] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio access technologies such as IEEE 802.16 (Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like.

[0024] As an example, Figure 1A The base station 114b in the example may be a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may use any appropriate RAT to facilitate wireless connectivity in a local area such as a business location, a residence, a vehicle, a campus, or the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may establish a wireless local area network (WLAN) by implementing a radio technology such as IEEE 802.11. In another embodiment, the base station 114b and the WTRUs 102c, 102d may establish a wireless personal area network (WPAN) by implementing a radio technology such as IEEE 802.15. In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may establish a picocell or a femtocell by using a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, or LTE-A, etc.). Figure 1A As shown, the base station 114b can be directly connected to the Internet 110. Thus, the base station 114b does not need to access the Internet 110 via the core network 106.

[0025] The RAN 104 may be in communication with a core network 106, which may be any type of network configured to provide voice, data, application and / or voice over Internet Protocol (VoIP) services to one or more WTRUs 102a, 102b, 102c, 102d. For example, the core network 106 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions such as user authentication. Although Figure 1AAlthough not shown, it will be appreciated that the RAN 104 and / or the core network 106 may be in direct or indirect communication with other RANs, and that these RANs may employ the same RAT as the RAN 104 or different RATs. For example, in addition to being connected to the RAN 104, which may employ E-UTRA radio technology, the core network 106 may also be in communication with another RAN (not shown) employing GSM radio technology.

[0026] The core network 106 may also act as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer network devices that use a common communication protocol, and the protocol may be the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another core network connected to one or more RANs, which may use the same RAT as the RAN 104 or a different RAT.

[0027] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities, that is, the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links. Figure 1A The illustrated WTRU 102c may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0028] Figure 1B is a system diagram of an example WTRU 102. Figure 1B As shown, the WTRU 102 may include a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a numeric keypad 126, a display / touchpad 128, a non-removable memory 130, a removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and peripherals 138. It should be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0029] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which in turn may be coupled to the transmit / receive element 122. Although Figure 1B The processor 118 and the transceiver 120 are depicted as separate components, however it should be appreciated that the processor 118 and the transceiver 120 may also be integrated into one electronic package or chip.

[0030] The transmit / receive component 122 may be configured to transmit or receive signals to and from a base station (e.g., base station 114a) via the air interface 116. For example, in one embodiment, the transmit / receive component 122 may be an antenna configured to transmit and / or receive RF signals. As an example, in another embodiment, the transmit / receive component 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals. In yet another embodiment, the transmit / receive component 122 may be configured to transmit and receive RF and light signals. It should be appreciated that the transmit / receive component 122 may be configured to transmit and / or receive any combination of wireless signals.

[0031] In addition, although Figure 1B 102 as a single component, but the WTRU 102 may include any number of transmit / receive components 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive components 122 (e.g., multiple antennas) for transmitting and receiving radio signals via the air interface 116.

[0032] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As described above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers that allow the WTRU 102 to communicate via multiple RATs, such as UTRA and IEEE 802.11.

[0033] The processor 118 of the WTRU 102 may be coupled to a speaker / microphone 124, a numeric keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit), and may receive user input data from these components. The processor 118 may also output user data to the speaker / microphone 124, the numeric keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store information in any suitable memory such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as, for example, on a server or a home computer (not shown).

[0034] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power for use by other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (Ni-Cd), nickel-zinc (Ni-Zn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0035] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) related to the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) via the air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information using any suitable positioning method while remaining consistent with an embodiment.

[0036] The processor 118 may also be coupled to other peripheral devices 138, which may include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripheral devices 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos or videos), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, module, FM radio unit, digital music player, media player, video game console module or Internet browser, etc.

[0037] Figure 1C Shown is a system diagram of an example RAN 104 and an example core network 106 in accordance with an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the core network 106.

[0038] The RAN 104 may include eNode-Bs 140a, 140b, 140c, however it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. Each of the eNode-Bs 140a, 140b, 140c may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 140a, 140b, 140c may implement real-time MIMO technology. Thus, for example, the eNode-B 140a may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a.

[0039] Each eNodeB 140a, 140b, 140c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, uplink and / or downlink user scheduling, etc. Figure 1C As shown, the eNode-Bs 140a, 140b, 140c may communicate with one another over an X2 interface.

[0040] Figure 1C The illustrated core network 106 may include a mobility management gateway (MME) 142, a serving gateway 144, and a packet data network (PDN) gateway 146. Although each of the foregoing components are described as being part of the core network 106, it should be appreciated that any of these components may be owned and / or operated by an entity other than the core network operator.

[0041] The MME 142 may be connected to each of the eNode-Bs 140a, 140b, 140c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 142 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, performing bearer activation / deactivation processing, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 142 may also provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM or WCDMA.

[0042] The serving gateway 144 may be connected to each of the eNode-Bs 140a, 140b, 140c in the RAN 104 via an S1 interface. The serving gateway 144 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The serving gateway 144 may also perform other functions such as anchoring the user plane during inter-eNode-B handovers, triggering paging processing when downlink data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0043] The serving gateway 144 may also be connected to a PDN gateway 146, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0044] The core network 106 may facilitate communications with other networks. For example, the core network 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks such as the PSTN 108 to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the core network 106 may include or be in communication with an IP gateway, such as an IP Multimedia Subsystem (IMS) server, which may serve as an interface between the core network 106 and the PSTN 108. In addition, the core network 106 may provide the WTRUs 102a, 102b, 102c with access to the networks 112, which may include other wired or wireless networks that are owned and / or operated by other service providers.

[0045] A wireless communication system compliant with the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) can support rates of up to 100 megabits per second (Mbps) in the downlink (DL) and up to 50 Mbps in the uplink (UL) for a 2x2 configuration. The LTE DL scheme can be based on an orthogonal frequency division multiple access (OFDMA) air interface. Each radio frame can be composed of 10 subframes of 1 millisecond (ms) each. Each subframe can be composed of two time slots of 0.5 ms each. Each time slot can have seven or six orthogonal frequency division multiplexing (OFDM) symbols. If there are seven symbols per time slot, it can be used with a normal cyclic prefix (CP) length, and if there are six symbols per time slot, it can be used with an extended CP length. The subcarrier spacing for a specific specification can be 15 kilohertz (kHz). In addition, a reduced subcarrier spacing mode using 7.5 kHz is also possible. Frames and radio frames can be used interchangeably.

[0046] One resource element (RE) may correspond to one subcarrier in one OFDM symbol interval. 12 consecutive subcarriers in a time slot of 0.5 ms may constitute one resource block (RB). If each time slot has seven symbols, each RB may include 12×7=84 REs.

[0047] The basic time domain unit for dynamic scheduling processing can be a subframe consisting of two consecutive time slots. This unit may sometimes be referred to as an RB pair. On some OFDM symbols, some subcarriers thereon may be allocated to carry pilot or reference signals on the time-frequency grid. In order to meet the spectrum masking requirements, multiple subcarriers at the edge of the transmission bandwidth will not be transmitted.

[0048] Uplink channels that may be provided and / or used include a physical UL shared channel (PUSCH) and / or a physical UL control channel (PUCCH). A wireless transmit / receive unit (WTRU) may transmit control information called UL control information (UCI) on the PUSCH or PUCCH (e.g., in a subframe), or part of the information may be transmitted on the PUCCH and part may be transmitted on the PUSCH. The UCI may include one or more of the following: a hybrid automatic repeat request (HARQ) acknowledgement (ACK) / negative acknowledgement (NACK), a scheduling request (SR), and / or channel state information (CSI), wherein the CSI may include one or more of the following: a channel quality indicator (CQI), a precoding matrix indicator (PMI), and a rank indicator (RI). Resources that may be allocated for PUCCH transmission may be located at or near the edge of the UL frequency band.

[0049] Downlink channels that may be provided and / or used include a physical downlink shared channel (PDSCH) and / or a downlink control channel, wherein the downlink control channel may include one or more of the following: a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), a physical downlink control channel (PDCCH) and / or an enhanced PDCCH (EPDCCH).

[0050] Depending on the control channel overhead, the first 1-3 OFDM symbols of each subframe in the DL may be occupied by one or more of the PCFICH, PHICH, and PDCCH, and the occupied symbols may be referred to as the DL control region. The PCFICH may be transmitted in the first OFDM symbol (e.g., symbol 0) of each subframe, and / or the PCFICH may indicate the number of OFDM symbols used for the DL control region in the subframe. The WTRU may detect the control format indicator (CFI) from the PCFICH, and the DL control region may be defined in the subframe according to the CFI value. If the subframe may be defined as a subframe that is not supported by PDSCH, the PCFICH may be skipped. DL symbols that do not belong to the DL control region may be referred to as a data or PDSCH region. EPDCCH may be provided and / or used in the PDSCH region. The location of the EPDCCH in the region may be signaled to the WTRU that may (or is expected to) monitor, receive, or otherwise use the EPDCCH (e.g., by means of higher layer signaling, such as radio resource control (RRC) signaling). The PDCCH and / or EPDCCH may provide control information for UL and / or DL ​​transmission, resource allocation (eg, grant), and the like.

[0051] DL signals and / or channels may be provided or transmitted by an eNodeB and / or may be received and / or used by a WTRU. UL signals and / or channels may be provided or transmitted by a WTRU and / or may be received and / or used by an eNodeB.

[0052] The signal and / or channel may be associated with a cell corresponding to a certain carrier frequency and / or geographic area. The carrier frequency may be the center frequency of the cell (e.g., the center frequency of the bandwidth supported by the cell). An eNodeB may have one or more cells associated with it. In some embodiments, eNodeB and cell may be used interchangeably.

[0053] As an example, an eNodeB or cell may provide or transmit synchronization signals including a primary synchronization signal (PSS) and / or a secondary synchronization signal (SSS). Such signals may be used by the WTRU to acquire time and / or frequency synchronization with the eNodeB or cell. The PSS and / or SSS may be present in subframes 0 and / or 5 and may be present in every radio frame. Transmissions may be performed on 62 subcarriers located at the center of the cell bandwidth, and 5 subcarriers on each side of the 62 subcarriers may be reserved or unused. For frequency division duplex (FDD), PSS transmissions may be performed in the last OFDM symbol of slot 0 (e.g., the first slot of subframe 0) and slot 10 (e.g., the first slot of subframe 5) of each radio frame, and SSS transmissions may be performed in the second to last (e.g., next to the last) OFDM symbol. For time division duplex (TDD), PSS transmission may be performed in the third OFDM symbol in subframes 1 and 6 of each radio frame, and SSS may be transmitted in the last OFDM symbol in slot 1 (e.g., the second slot of subframe 0) and slot 11 (e.g., the second slot of subframe 5) of each radio frame. The synchronization signal may convey information related to the physical cell identity (cell ID) of the cell.

[0054] The physical broadcast channel (PBCH) transmitted by the eNodeB may carry very important cell information, such as the master information block (MIB). The PBCH may be provided or transmitted in subframe 0 of each radio frame and may be repeated in each of four consecutive radio frames (e.g., a 40 ms period). The PBCH may be transmitted in the first four OFDM symbols of the second slot of subframe 0 and may be transmitted on the 72 center subcarriers. The MIB may provide information such as the DL bandwidth of the cell, PHICH information, and at least a portion of the system frame number (SFN), such as the 8 most significant bits of a 10-bit SFN.

[0055] The downlink reference signal may include a cell-specific reference signal (CRS) and / or a channel state information reference signal (CSI-RS), and / or a demodulation reference signal (DM-RS), and / or a positioning reference signal (PRS). The WTRU may receive and / or use a DL reference signal. The WTRU may use the CRS to perform channel estimation in order to coherently demodulate a downlink physical channel other than certain DL channels (e.g., any), wherein the certain DL channels may include at least one of PMCH, EPDCCH, and PDSCH when TM7, TM8, TM9, or TM10 are configured. As an example, if the WTRU is configured with a transmission mode that uses CRS to perform PDSCH demodulation, the WTRU may use CRS for channel state information measurement in order to report CQI, PMI, and / or RI. The WTRU may use CRS to perform cell reselection and / or mobility-related measurements. The CRS may be received in certain subframes (e.g., any subframe), and the supported antenna ports may be up to four. The WTRU may use DM-RS to demodulate certain channels, where the certain channels may include at least one of the following: EPDCCH and PDSCH configured with TM7, TM8, TM9 or TM10. The DM-RS for demodulating a channel (e.g., EPDCCH or PDSCH) may be transmitted in a resource block assigned to the channel (e.g., EPDCCH or PDSCH). For CSI-RS transmitted with a certain duty cycle, it may be used by the WTRU for channel state information measurement, for example, when the WTRU is configured with a transmission mode in which DM-RS may be used to perform PDSCH demodulation, wherein the mode does not include certain modes, such as TM7 and / or TM8. In addition, CSI-RS may also be used for cell selection and mobility-related measurements, for example, when the WTRU is configured with a certain transmission mode (e.g., TM10). The WTRU may use PRS to perform location-related measurements.

[0056] For LTE TDD, multiple TDD uplink and downlink subframe configurations may be supported, and one of the configurations may be used in the eNode B. Each TDD uplink and downlink subframe configuration may include a downlink subframe "D", an uplink subframe "U", and a special subframe "S" as shown in Table 1.

[0057] Table 1 is an example of TDD LTE uplink-downlink configuration. Table 1

[0058] Conventional cellular systems (e.g., LTE systems) can use licensed spectrum. Operators can obtain (e.g., through government auctions) the right to use a portion of a frequency band in certain areas to transmit and receive cellular signals. As an example, by using licensed spectrum, an operator can use the spectrum exclusively to provide services to its users without worrying about in-band interference from other operators' systems.

[0059] Cellular operators may consider using unlicensed bands traditionally used for non-cellular services and applications (e.g., WiFi) as a secondary tool to enhance their service offerings in order to meet the growing high demand for broadband data. One of the deployment scenarios being considered may use carrier aggregation. In this scenario, called Licensed Assisted Access (LAA), the primary component carrier (or serving cell) (PCell) may be a licensed carrier (e.g., a carrier that can use licensed spectrum). The unlicensed carrier (e.g., a carrier that can use unlicensed spectrum) may be a secondary component carrier (or serving cell) (SCell) that can be aggregated with the PCell.

[0060] Figure 2 is a system diagram of an illustrated LAA scenario. In one example, one or more unlicensed SCells and zero, one or more authorized SCells may be aggregated together and / or aggregated with a PCell. The PCell may be an authorized LTE PCell. In the example shown in scenario 200, WTRU 202a may use SCells or secondary carriers 211, 212, 213 and PCell or primary carrier 220. WTRU 202b may use SCells or secondary carriers 215, 216, 217 and PCell or primary carrier 230. With carrier aggregation, the PCell and SCells may belong to the same eNode B. In another deployment scenario, dual connectivity may be used, in which one or more unlicensed carriers and the authorized PCell may belong to different eNode Bs.

[0061] When considering LTE operation in unlicensed spectrum, as an example, coexistence between LTE and other unlicensed technologies (e.g., Wi-Fi) and LTE operators may be considered in an attempt to minimize interference and provide fairness among spectrum users. Mechanisms such as listen before talk (LBT) and transmission gaps may be used. With LBT, system nodes such as access points (APs), eNodeBs (eNodeBs), and wireless transmit / receive units (WTRUs) may listen to a channel (e.g., a frequency band having a certain center frequency and bandwidth) to determine if the channel is being used by another user before transmitting over the signal or a portion of the channel.

[0062] Figure 3is a system diagram of an example LAA system using LBT. In one example, the listening and / or decision processing used by another node may include or be based on measurements including energy detection. By using transmission gaps, a system node that may perform transmissions on a channel or a portion of a channel may include or ensure that there are gaps in its transmissions, as an example, thereby allowing other potential users to treat the channel as idle and / or use the channel. In one example, if other potential users detect that the energy is above a threshold, they will not use the channel. In the example shown in system 300, an LAA cell user may remain silent while other users are using channel 320. The LAA cell user may then detect an idle period 330. The LAA cell user may then use channel 340. Further, hidden nodes may cause interference that the LAA cell cannot detect.

[0063] LTE operation in unlicensed spectrum may or may not be combined with operation in licensed spectrum (for example, with or without aggregation or dual connectivity with a licensed PCell), and may be referred to as LTE unlicensed operation or LTE-U. The terms Wi-Fi, WiFi, and Wifi are used interchangeably herein.

[0064] The use of coexistence mechanisms (e.g., LBT and transmission gaps) may create transmission and / or reception issues and / or new scenarios with respect to LTE-U that need to be addressed. These issues and / or scenarios may be due to the presence of the gaps themselves. For example, existing measurement and reporting mechanisms in LTE may use or be based on periodically provided signals, but these mechanisms are not applicable to or optimized for LTE-U operations that involve gaps in the transmission of some signals.

[0065] In some embodiments described herein, the terms "eNode B" and "cell" may be used interchangeably. In some embodiments, the terms "unlicensed" and "licensed-free (LE)" may be used interchangeably. In some embodiments, operate may be used interchangeably with transmit and / or receive. In some embodiments, the term "component carrier" may be used interchangeably with "serving cell."

[0066] LTE-U eNodeB can be an eNodeB or cell that can transmit and / or receive one or more LTE channels (e.g., physical channels) and / or signals, and / or can operate in an unlicensed (LE) band (e.g., transmit and / or receive signals). LTE-U eNodeB can transmit and / or receive one or more LTE channels and / or signals in a licensed band and / or LE band. In the LE band available for LTE-U eNodeB to work, one or more other radio access technologies (RATs) (e.g., Wi-Fi), one or more other LTE-U eNodeBs, and / or one or more WTRUs can exist therein or operate therein. In some embodiments, the terms "eNodeB" and "LTE-U eNodeB" can be used interchangeably. In some embodiments, WTRU can replace eNodeB and / or vice versa, and is still consistent with the present disclosure. In some embodiments, UL can replace DL and / or vice versa, and is still consistent with the present disclosure. The terms "LTE-U" and "LAA" can be used interchangeably with each other, and are still consistent with the present disclosure.

[0067] In some embodiments, a channel may refer to a frequency band that may have a center or carrier frequency and a bandwidth. Licensed and / or unlicensed spectrum may include one or more channels that may or may not overlap. The terms channel, frequency channel, radio channel, and LE channel may be used interchangeably. Accessing a channel may be the same as using the channel (e.g., transmitting and / or receiving on or using the channel).

[0068] In some embodiments, a channel may refer to an LTE channel or signal, such as an uplink or downlink physical channel or signal. Downlink channels and signals may include one or more of PSS, SSS, PBCH, PDCCH, EPDCCH, and PDSCH. Uplink channels and signals may include one or more of PRACH, PUCCH, SRS, and PUSCH. Channels and LTE channels may be used interchangeably. Channels and signals may be used interchangeably.

[0069] In some embodiments, data / control may refer to data and / or control signals and / or channels. Control may include synchronization. Data / control may be LTE data / control. The terms data / control and data / control channels and / or signals may be used interchangeably. Channels and signals may be used interchangeably. LTE and LTE-A may be used interchangeably.

[0070] In some embodiments, a channel resource may be a resource (e.g., a 3GPP LTE or LTE-A resource) that at least occasionally carries one or more channels and / or signals, such as time and / or frequency resources. In some embodiments, a channel resource may be used in conjunction with a channel and / or signal exchange.

[0071] Reference signal, CSI-RS, CRS, DM-RS, DRS, measurement reference signal, reference resource for measurement, CSI-interference measurement (IM), and measurement RS are used interchangeably. SCell, secondary cell, LTE-U cell, authorized secondary cell, unauthorized cell, and LAA cell are used interchangeably. PCell, primary cell, LTE cell, and authorized cell are used interchangeably. Interference and interference plus noise are used interchangeably.

[0072] Disclosed herein are methods and apparatus for using LTE-U, LTE unlicensed bands, LAA, busy signals, and / or synchronization signals. Disclosed herein are methods and apparatus for performing measurement processing for LTE cells in unlicensed bands when the signals and resources to be measured cannot be provided regularly. Dynamic indications of signal and resource presence (e.g., including start and duration) may indicate availability of measurements, such as PSS / SSS, CRS, CSI-RS, and CSI-IM that may be used for interference measurements. Dynamic requests for measurements and measurement reports may indicate the presence / absence of signals and / or resources for measurement, such as reference signal received power (RSRP), reference signal received quality (RSRQ), CSI, received signal strength indicator (RSSI), and / or interference (e.g., using CSI-IM).

[0073] Disclosed herein are methods and apparatus for reducing interference and enabling LAA resource sharing between LAA cells by dynamically changing signal and resource locations. Disclosed herein are methods and apparatus for hidden node measurement and reporting. Interference measurements may be triggered and / or reported with a timestamp / time window to enable an eNodeB to correlate with the eNodeB's own measurements and detect hidden nodes. During transmission, interference measurements on resources (e.g., CSI-IM) may be dynamically requested (e.g., in a DL grant).

[0074] CSI reporting optimization methods and apparatus are disclosed herein. On-demand resource identification and reporting timing for enabling CSI reporting during active time of LAA cells. Methods and apparatus for new measurement types are disclosed herein, wherein the types may include, but are not limited to, the following example types: enhanced RSSI (eRSSI), interference, SINR, and / or radar detection. Methods and apparatus for opportunistic measurement and reporting are disclosed herein. And methods and apparatus for dynamically indicating measurement reports are disclosed herein.

[0075] If the presence or availability of a signal or channel is irregular (e.g., periodic) or not in accordance with a known or configured schedule, the WTRU may or may need to measure the signal or channel or one or more characteristics of the signal or channel (e.g., power, signal-to-interference-plus-noise ratio (SINR), and signal-to-noise ratio (SNR), etc.). For example, in an LTE cell, a reference signal (e.g., CRS) is present in all DL subframes, while in a cell that cancels the transmission of reference signals (e.g., LTE-U or LAA cells), such a reference signal may (or may only) be available at some times or in some DL subframes and unavailable at other times, such as during off periods, LBTs, or transmission gaps. If the WTRU does not know when a signal that it may or may need to measure is present or absent, measurement accuracy and / or system performance may be affected.

[0076] In one example, a WTRU may receive an indication from an eNodeB or cell that informs the WTRU when one or more signals and / or channels that may be used to perform measurements (e.g., by the WTRU) are present or absent (e.g., transmitted or not transmitted by the eNodeB or cell or another eNodeB or cell). As an example, the indication may be provided dynamically via physical layer signaling, such as provided in a downlink control information (DCI) format. The indication may include resources where the one or more signals and / or channels may be present or absent, including time and / or frequency resources. These resources may be referred to as channel resources. The indication may include a request to perform and / or report at least one measurement result (e.g., using the indicated one or more signals and / or channels and / or channel resources). The indication may be referred to as a signal presence indication or a measurement indication, and these terms may be used interchangeably. The indication may include or include an identifier (e.g., an explicit identifier) ​​of one or more signals and / or channels that may be used for measurement.

[0077] In some examples, the indication may include channel resources that may be used for measurement, and may or may not include information relating to or identifying signals and / or channels related to the measurement. These channel resources may be used (e.g., for the WTRU) to measure one or more signals and / or channels from (or transmitted by) an eNodeB or cell (e.g., a serving eNodeB or cell of the WTRU). In the absence of some or all signals and / or channels from (or transmitted by) an eNodeB or cell (e.g., a serving eNodeB or cell of the WTRU), these channel resources may be used (e.g., by the WTRU) for one or more measurements (e.g., for measuring interference).

[0078] In another example, a WTRU may receive an indication (e.g., from an eNodeB) that informs the WTRU on which time and / or frequency resources (e.g., channel resources) the WTRU may perform measurements on. The indication may be provided dynamically, for example, by means of physical layer signaling (e.g., in a DCI format). As an example, the indication may include a request to use the indicated channel resources to perform and / or report at least one measurement. These channel resources may be used (e.g., by the WTRU) to measure one or more signals and / or channels that may be from (or transmitted by) an eNodeB or cell (e.g., a serving eNodeB or cell of the WTRU). In the absence of some or all signals and / or channels from (or transmitted by) an eNodeB or cell (e.g., a serving eNodeB or cell of the WTRU), the channel resources may be used (e.g., by the WTRU) for one or more measurements (e.g., for measuring interference).

[0079] Signals and / or channels that can be used for measurement may be referred to as measurement-related signals. Measurement-related signals may be or may include one or more of the following (e.g., a combination thereof): synchronization signals, reference signals, PSS, SSS, CRS, CSI-RS, DM-RS (or DMRS), and / or PRS. Channel resources that can be used for measurement may be referred to as measurement-related channel resources. Measurement-related channel resources may be or may include channel resources that can carry at least one measurement-related signal. Measurement-related channel resources may be or may include channel resources that can be used for measurement and do not contain signals and / or channels (e.g., for or from a certain eNodeB or cell, such as a serving eNodeB or cell of a WTRU). Measurement-related channel resources may be or may include one or more of CSI-RS and / or CSI-IM channel resources. CSI-RS may be or may include zero-power CSI-RS.

[0080] As an example, the WTRU may perform measurements on zero-power CSI-RS and / or CSI-IM channel resources in order to measure or determine the presence of interference.

[0081] The measurement-related signals and the measurement-related channel resources may be used interchangeably. The WTRU may use the indicated signals and / or channels and / or channel resources to perform measurements, where the measurements may be performed in response to a measurement request. The WTRU may report the measurement results in response to the request and / or in response to a measurement trigger. Dynamic and / or on-demand signal indications, channel resource indications and / or measurement requests may enable more optimized measurements for LTE-U.

[0082] In one example, an LTE-U cell may wait to use an unlicensed frequency channel until it detects that the channel is idle and / or may maintain (e.g., use or continue to use) the unlicensed frequency channel for a short time (e.g., 4-12 milliseconds). The time during which a frequency channel is available for use by an LTE-U cell (or for transmission on it) may be referred to as the active time of the cell. A cell may or may only transmit signals (including measurement-related signals) during its active time. Preconfigured measurement periods may not coincide with the active time. An LTE-U cell (or its associated eNodeB) may use (e.g., transmit to a WTRU) one or more measurement indications to enable and / or request measurements that are aligned (e.g., better aligned) with at least a portion of the active time, wherein the measurement indications may be dynamic or on-demand.

[0083] In another example, an LTE-U cell (or its associated eNodeB) may change the resources on which channels and / or signals may be transmitted, for example dynamically or over time. The eNodeB or cell may adapt its (or cell's) transmission to the presence of interference by changing the resources, and / or allow multiple LTE-U cells to share frequency channels. The eNodeB or cell may include channel resources in the measurement indication, which enables one or more measurements to take these changes into account.

[0084] In another example, an LTE-U cell (or its associated eNodeB) may change the resources on which the cell cannot transmit (or transmit with zero power) channels and / or signals, for example dynamically or with activity time. As an example, the eNodeB or cell may dynamically specify the target of interference measurements in time and / or frequency by changing the resources, and / or may be able to perform interference measurements on some resources while the cell is performing transmissions on other resources. The eNodeB or cell may include channel resources in the measurement indication, which enables one or more measurements to take these changes into account.

[0085] Not transmitting and transmitting with zero power are used interchangeably. An absent or missing signal may be a signal transmitted with zero power, and vice versa.

[0086] One or more channel resources may be indicated in the time domain and / or frequency domain. The time domain indication may include or indicate one or more of the following: one or more subframes, one or more time slots, one or more OFDM symbols, one or more time samples, and / or one or more frames, etc. The time unit (e.g., subframe, frame, symbol, etc.) may be an LTE time unit.

[0087] The frequency domain indication may include or indicate one or more of the following: a carrier frequency (which may be represented by an E-UTRA Absolute Radio Frequency Channel Number (EARFCN) as an example), a bandwidth, one or more subcarriers, and / or one or more subcarrier sets (e.g., a set of 12 subcarriers corresponding to an RB or RB pair), etc. The frequency domain indication may (or may be used to) include or indicate one or more RBs (or RB pairs). This may be applied when the time domain (e.g., one or more time slots or subframes) of the one or more RBs (or RB pairs) is known or understood (e.g., by the WTRU).

[0088] A resource element (RE) may correspond to a subcarrier in an OFDM symbol interval. RE may be an example of a channel resource that may be indicated and / or defined and / or identified in the time domain and the frequency domain. RB or physical RB (PRB) may indicate and / or define and / or identify a set of channel resources in the time domain and the frequency domain or in the frequency domain (e.g., only the frequency domain).

[0089] RB and PRB can be used interchangeably. RB (or PRB) can be used to represent a certain number of subcarriers, such as 12 subcarriers. RB (or PRB) can correspond to a time slot. The term RB (or PRB) can be used to represent a RB (or PRB) pair corresponding to 2 time slots (e.g., of a subframe). As an example, if there is no frequency hopping, the set of subcarriers corresponding to each RB in the RB pair can be the same, and if there is frequency hopping, the set will be different.

[0090] A channel resource may be indicated or identified by one or more of the following: one or more RBs, one or more RB sets, one or more REs, and / or one or more RE sets.

[0091] The WTRU may receive a measurement indication and / or the eNodeB may transmit a measurement indication. The WTRU may receive a measurement indication from the eNodeB. The measurement indication may include an indication of one or more channel resources that may contain or carry measurement-related signals. For example, the measurement indication may include or identify a set of PRBs and / or REs that may carry (or not carry) measurement-related signals (and / or other one or more signals) (e.g., CRS or CSI-RS), wherein the measurement-related signals may be present in the set of PRBs and / or REs according to a rule, which may be a rule for authorizing LTE. As an example, the time position in the subframe may be known or determined without an explicit indication.

[0092] In one example, a bitmap may be used to indicate one or more PRBs. The presence of a signal may correspond to a certain value, such as 1, and the absence of a signal may correspond to another value, such as 0. In another example, the indication may include one or more of a starting PRB, a center PRB, a number of PRBs, and / or a bandwidth.

[0093] The measurement indication may include an indication of one or more channel resources that may not contain or carry one or more (eg, any) measurement-related signals (or one or more or any other signals) and that may be used for interference measurement.

[0094] Whether a channel resource can carry measurement-related signals or other signals may correspond to whether one or more of the following may send measurement-related signals or other signals in a channel resource: an eNodeB or cell that may transmit a measurement indication, a serving eNodeB of the WTRU, a serving cell of the WTRU, an LTE-U cell, and / or an LTE-U cell such as a WTRU and / or a serving eNodeB of the WTRU that may be configured and / or activated.

[0095] The measurement indication may correspond to one or more measurement-related signals and / or measurement types, such as CRS measurement, CSI-RS measurement, PSS and / or SSS measurement, and one or more of the following: RSRP, RSRQ, RSSI measurement, and CSI-IM measurement, etc. The measurement indication may include the one or more signals and / or the one or more types explicitly, such as by a value that can be configured by the eNB to correspond to the one or more signals and / or measurement types. The one or more signals and / or the one or more types may be implicitly indicated, such as by a DCI format of the measurement indication or an RNTI used to scramble the CRC of the DCI format. The WTRU may receive different measurement indications for different measurement-related signals and / or measurement types.

[0096] Based at least on the measurement indication that may indicate the presence or absence of a measurement-related signal and / or the measurement type, the WTRU may expect the presence or absence of the indicated signal (or one or more signals associated with the measurement type) on the indicated channel resources (e.g., in time and / or frequency). The WTRU may use (or may also use) other information to determine the time and / or frequency resources where the signal is present or absent, such as a configuration received from the eNodeB, a priori known time and / or frequency locations, etc.

[0097] The WTRU may perform measurements on channel resources determined in accordance with the measurement indication and / or one or more other indications, definitions, or rules. For example, the WTRU may perform measurements on channel resources determined from a combination of the measurement indication and a definition or rule for authorized LTE. In one example, the frequency resources (e.g., RBs) of the signal may be included in the measurement indication, while the time resources (e.g., symbols in a subframe) may be equivalent to the resources defined for LTE. In another example, the time resources (e.g., symbols in a subframe) of the signal may be included in the measurement indication, while the frequency resources (e.g., RBs) may be equivalent to the resources defined for LTE.

[0098] The period of time during which a WTRU may perform a measurement (e.g., a measurement) may be referred to as a "measurement period" and may be expressed in milliseconds (ms or msec), frames, subframes, time slots, OFDM symbols, and time samples, etc. "Measurement indication" and "measurement period indication" may be used interchangeably.

[0099] The measurement indication and / or the time domain indication may include an indication of a measurement period and / or an indication of one or more parameters of the measurement period, wherein the parameters may include at least one of the following: a start time, an end time, a time length, and a time pattern. The measurement indication may include or identify the start of the measurement period. The measurement indication may include or identify one or more of the following: a first frame, a first subframe, a first time slot, a first OFDM symbol, and / or a first time sample of the measurement period. The WTRU may receive the measurement period start indication implicitly and / or explicitly.

[0100] In one example, the WTRU may receive a measurement indication in subframe n. The measurement indication may be provided and / or received in a DCI signal or format. The measurement indication in subframe n and / or the receipt of a measurement indication in subframe n may indicate that the measurement period starts at subframe n+x. The value of x may be dynamic, such as indicated in the same DCI, and / or may be configured, such as by signaling (e.g., higher layer (e.g., RRC) signaling from an eNode B). The value of x may be a fixed or known value, such as 0, 1, 2, 3, or 4. For TDD, the value of x may depend on the TDD UL / DL configuration of the LAA cell. The value of x may be 0, indicating that the measurement period starts at the same subframe as the subframe in which the measurement indication is received. The value of x will not be included in the DCI.

[0101] In another example, the WTRU may use the start of the activity time of the LAA cell as the start of the measurement period. The start of the activity time may be indicated explicitly, such as by a DCI format indication from the eNodeB, or may be blindly determined by the WTRU, such as based on detection of one or more signals (e.g., one or more of the PSS, SSS, CRS, and busy signals, etc.).

[0102] The measurement indication may include or identify the end of the measurement period. The measurement indication may include or identify the last subframe and / or time slot and / or OFDM symbol and / or time sample of the measurement period. The WTRU may receive the measurement period end indication implicitly and / or explicitly.

[0103] In one example, the WTRU receives a measurement indication in subframe n. The measurement indication may be provided and / or received in a DCI signal or format. The measurement indication in subframe n and / or the receipt of the measurement indication in subframe n may indicate that the measurement period ends in subframe n+x. The value of x may be dynamic, such as indicated in the same DCI, and / or may be configured, such as by signaling (e.g., higher layer (e.g., RRC) signaling from an eNodeB). The value of x may be a fixed or known value, such as 0, and this will indicate that the measurement period will end in subframe n+0 (e.g., the subframe in which the measurement indication may be received). The value of x will not be included in the DCI.

[0104] In another example, the WTRU may use the end of the active time of the LAA cell as the end of the measurement period. The end of the active time may be indicated by the eNodeB, for example, by a DCI format. The end of the active time may also be determined by the WTRU from one or more indications (e.g., provided by the eNodeB), such as the start of the active time, the duration of the active time, the amount of time to the end of the active time, such as the first time the WTRU can be scheduled with resources on the LAA cell. The one or more indications may be provided and / or received in physical layer signaling (e.g., DCI format). The end of the active time may be determined by the WTRU based on the absence of one or more signals or the measurement results of one or more signals being below a threshold. The one or more signals may include one or more measurement-related signals, such as PSS, SSS, and CRS.

[0105] The measurement indication may include or identify the length of the measurement period. The length may be expressed in terms of one or more of a plurality of frames, subframes, time slots, OFDM symbols, and time samples, etc. The WTRU may use the indication of the measurement period length and the start of the measurement period to calculate or determine the end of the measurement period. The WTRU may use the indication of the measurement period length and the end of the measurement period to calculate or determine the beginning of the measurement period. For example, the WTRU may receive an indication of the measurement period length y in subframe n. If the beginning of the period may be in subframe n+x, then the WTRU may determine that the period ends in subframe n+x+y.

[0106] After the measurement period starts and / or during the measurement period (or during its length) for a particular measurement, the WTRU may start performing measurements, or may continue to perform measurements. The WTRU may combine new measurements of a certain type with previous (e.g., stored) values ​​of the same type, for example, the WTRU may use the new measurements in a filtered or averaged version of the measurements. As an example, the WTRU may perform measurements on at least the channel resources indicated by the measurement indication.

[0107] Once a measurement period ends or the duration of a measurement period for a certain measurement ends, the WTRU may stop performing the measurement. For a measurement type, the WTRU may store a plurality of measurement results (e.g., measurement samples) and / or typical values ​​(e.g., filtered or averaged values) that may be used by the WTRU (e.g., when the measurement is reactivated later). The WTRU may report the measurement or values ​​related to the measurement to the eNodeB.

[0108] The measurement indication may include or identify a pattern of a time unit or a time period for a measurement period. The pattern may be referred to as a measurement pattern. The measurement pattern may include or identify a pattern of subframes and / or time slots and / or OFDM symbols and / or time samples that may constitute, compose or be included in the measurement period. For a measurement-related signal that may be indicated as existing or measured in a measurement period having a certain time unit pattern (e.g., a subframe pattern), the signal may or may only exist (e.g., be transmitted by an eNodeB) in a time unit (e.g., a subframe) indicated by the pattern. The measurement-related signal will not exist (e.g., will not be transmitted by an eNodeB) in other time units (e.g., subframes).

[0109] The absence of one or more signals (eg, all signals) may be indicated by a measurement pattern. The measurement pattern may indicate a pattern of time units where one or more (eg, all) signals may be absent (eg, not transmitted by the eNodeB).

[0110] For a measurement-related signal having a time unit (e.g., subframe) pattern, the WTRU may (or may only) consider or use channel resources (e.g., indicated or configured channel resources) located in the time unit (e.g., subframe) pattern indicated for measurement purposes. For example, the WTRU may receive a bitmap corresponding to subframes in a radio frame, such as "0101010101". The bitmap may indicate in which subframes one or more measurement-related information numbers may be present (or absent), such as in the second, fourth, sixth, eighth, and tenth subframes of a radio frame. The WTRU may (or may only) perform measurements on the channel resources of the one or more measurement-related signals in the indicated subframes (e.g., subframes indicated as present or absent according to the measurement type).

[0111] In another example, the pattern may be associated with the start of a measurement period, for example, every nth subframe may start with subframe n+k, where n may be a subframe in which a measurement indication or measurement pattern may be received, and k may be greater than or equal to 0. The measurement pattern may identify a particular time unit (e.g., a subframe) in which one or more signals are present or absent. The pattern may determine the measurement period. For example, the duration of the pattern may be the duration of the measurement period. The measurement pattern may (or may be assumed to be) repeated within the measurement period. Measurement-related signals may be present (or absent) and / or measured (e.g., by the WTRU) in time units (e.g., subframes) that fall within the pattern of the measurement period. The measurement pattern may be (or may be assumed to be) the same in one or more (e.g., all) frames within (e.g., at least partially within) the measurement period. Measurement-related signals may be present (or absent) and / or measured (e.g., by the WTRU) in time units that fall within the pattern of the measurement period.

[0112] Different LTE-U eNode Bs and / or cells may have or use different measurement patterns. For example, two or more LTE-U cells may be deployed on the same frequency channel and / or may be active at the same time. One or more of their measurement cycles may overlap in time. If their measurement patterns do not overlap, each LTE-U cell may transmit its measurement-related signals in accordance with its measurement pattern without interfering with the measurement-related signals of another LTE-U cell.

[0113] The measurement indication may include or identify an indication of one or more cells (e.g., LTE-U cells) and / or one or more frequency channels (e.g., LTE-U frequency channels, which may or may not correspond to active LTE-U cells) to which the measurement indication is applicable. The measurement indication may include or identify one or more cell IDs or a series of cell IDs. The measurement indication may include or identify one or more frequency channels (e.g., by an index corresponding to a list of configured LTE-U frequency channels).

[0114] The WTRU may receive measurement indications for one or more LTE-U cells. The WTRU may receive different measurement indications for different LTE-U cells.

[0115] A measurement indication or other mode or indication may (or may include an indication regarding the following processing) activate (or enable or start) and / or deactivate (or disable or stop) one or more measurement processes and / or mechanisms. A measurement indication may include an indication to start or stop performing one or more measurements that may be configured via physical layer and / or higher layer signaling (e.g., RRC signaling). An indication regarding the start of the activity time of an LAA cell may enable measurements associated with the LAA cell. An indication regarding the end of the activity time of an LAA cell or the end of the duration of the activity time of the cell may disable measurements associated with the LAA cell, and / or enable measurements associated with one or more other cells and / or channel users (or potential users).

[0116] In one example, the WTRU may receive an indication (e.g., from an eNodeB) that activates a set of measurements and / or measurement procedures and / or mechanisms that may (or may only) be applied to an LAA cell or to an LAA cell during active time. The measurement configuration may be provided separately and / or together with the indication (e.g., provided by an eNodeB). The indication may be the start of an active time of an LAA cell that may be displayed (e.g., via physical layer signaling) or may be blindly detected by the WTRU. The indication may be a measurement indication, or may be included in or included together with the measurement indication.

[0117] The WTRU may receive (e.g., from an eNodeB) an indication that the indication is to deactivate a set of measurements and / or measurement procedures and / or mechanisms that may (or may only) be applied to a LAA cell or to a LAA cell during active time. The indication may be the end of the active time of a LAA cell or the beginning of the inactive time of a LAA cell. The indication of the end of the active time may be replaced by the end of the active time duration.

[0118] The WTRU may receive an indication (e.g., from an eNodeB) that activates a set of measurements and / or measurement procedures and / or mechanisms that may be applied to the LAA cell during (or only during) the inactivity time (e.g., associated with the processing of measuring other LAA cells and / or WiFi users deployed on the same channel). The indication may be the end of the LAA cell activity time or the beginning of the LAA cell inactivity time. The indication of the end of the activity time may be replaced by the end of the activity time duration. The indication may be a measurement indication, or may be included in or included together with the measurement indication.

[0119] After receiving an indication to activate (or start or enable) certain measurements, the WTRU may start performing measurements or may continue to perform measurements. The WTRU may combine new measurement results of a certain type with previous (e.g., stored) values ​​of the same type, for example, the WTRU may use the new measurement results in a filtered or averaged version of the measurement. As an example, the WTRU may perform measurements on at least the channel resources indicated by the measurement indication.

[0120] Upon receiving an indication to deactivate (or stop or disable) certain measurements, the WTRU may stop performing the measurements. For a measurement type, the WTRU may store a plurality of measurement results (e.g., measurement samples) and / or typical values ​​(e.g., filtered values ​​or average values) that may be used by the WTRU (e.g., when the measurement is reactivated later). The WTRU may report values ​​about or associated with the measurements to the eNodeB.

[0121] The measurement indication may be provided in physical layer signaling (e.g., a DCI signal or format). The eNodeB may transmit the measurement indication, and / or the WTRU may receive the indication (e.g., from the eNodeB). The measurement indication and / or the RNTI that may be used to perform scrambling on the CRC format of the DCI format may be at least one of the following: cell-specific, WTRU-specific, or WTRU group-specific. As an example, the measurement indication may be provided or used for a WTRU group using a group RNTI. One or more WTRUs that may be configured with a group RNTI may receive the same measurement indication. The measurement indication may be provided with the aid of resources (e.g., PDCCH or EPDCCH) on a cell in a licensed spectrum (e.g., a PCell or other cell). The measurement indication may also be provided with the aid of resources (e.g., PDCCH or EPDCCH) on a cell in an unlicensed spectrum (e.g., an LAA cell or other cell to which the measurement indication is applied). The measurement indication may be included in signaling (e.g., a DCI format), wherein the signaling may be separate from or different from one or more other signaling (e.g., a DCI format), such as signaling (e.g., a DCI format) that may be defined or may be provided for a certain version (e.g., Release 12) of LTE. The measurement indication may be included in signaling (e.g., a DCI format) whose purpose or intent may be or may only be to provide the measurement indication. The measurement indication may be included in signaling (e.g., a DCI format) having at least one purpose or intent that is separate from or different from the measurement indication. For example, the measurement indication may be included with a DL grant (e.g., for resources on an LAA cell or channel).

[0122] The eNodeB may transmit and / or the WTRU may receive (e.g., from the eNodeB) configuration information associated with LAA measurements. The configuration information may be provided in higher layer signaling, such as RRC signaling. The configuration information may include parameters and / or sets of parameters referenced by an index or other identifier (e.g., in a measurement indication). For example, one or more sets of channel resources may be identified for one or more measurement-related signals and / or measurement types. In order to identify channel resources for measurement-related signals and / or measurement types, an index or identifier corresponding to the desired channel resource may be used in the measurement indication.

[0123] In another example, one or more measurement related signals and / or measurement types may be identified with one or more measurement patterns. To identify the measurement pattern of the measurement related signals and / or measurement types, an index or identity corresponding to the desired measurement pattern may be used in the measurement indication.

[0124] The eNodeB or cell providing the measurement indication may specify or determine that the measurement indication is cell-specific, WTRU-specific and / or group-WTRU-specific.

[0125] The measurement indication may be designated or determined to be cell-specific, WTRU-specific and / or group-WTRU-specific by the cell or frequency channel to which it is provided.

[0126] A cell-specific measurement indication may have an RNTI associated with it that may be known or used by some WTRUs (e.g., all WTRUs) in the cell. The measurement indication may (or may also) be provided to a WTRU or group of WTRUs in dedicated or group signaling (e.g., by using an RNTI such as a C-RNTI that may be known by or only to the WTRU or a group RNTI that may be known by or only to a group of WTRUs).

[0127] A measurement indication may be or may include a measurement request. A measurement request may be or may include a measurement indication. Embodiments applied to a measurement request may also be applied to a measurement indication, and vice versa, and remain consistent with the present disclosure. A measurement request and a measurement indication may be used interchangeably.

[0128] The measurement indication may request that one or more measurements be performed (e.g., on one or more resources indicated by the request). The measurement indication may request on-demand or aperiodic measurements, which may be performed, for example, using the indicated channel resources and / or on at least a portion of a measurement period that is indicated or otherwise known or determined.

[0129] The measurement request may be explicit (eg, a bit included in a measurement indication or other signaling or indication). The measurement request may be implicit, for example, a measurement indication for measuring a related signal may imply a request for related measurements.

[0130] The eNodeB may provide a measurement indication or request to one or more WTRUs. The WTRU receiving the indication or request may perform measurements, such as using the indicated channel resources and / or performing measurements in at least a portion of the indicated or otherwise known or determined measurement period. For example, the eNodeB may provide or use a measurement indication to the WTRU to indicate the presence of one or more signals (e.g., CRS) in a measurement period of a subframe. The eNodeB may indicate a starting subframe, or the starting subframe may be a subframe available for the eNodeB to provide the indication. The eNodeB may indicate the duration of the subframe in which the one or more signals may be present. For example, if the eNodeB may or expects to transmit one or more signals or signaling (which may include the indicated one or more signals, such as CRS) in at least N (e.g., the next N) subframes, then the eNodeB may indicate a measurement period of N subframes.

[0131] During at least a portion of a measurement period, the eNodeB may request the WTRU to perform and / or the WTRU may perform measurements, such as RSRP measurements. The WTRU may combine the measurements it performs during the measurement period with each other and / or with previous measurements to determine filtered, averaged, or otherwise combined measurement results that the WTRU may report and / or use to make reporting decisions.

[0132] The measurement request may be for the current LAA cell or channel or a different LAA cell or channel. The current LAA cell may be a cell that is configured as a serving cell and / or activated (e.g., for the WTRU to which the request is to be issued). The current LAA channel may be a frequency channel of the current LAA cell. The measurement request may include one or more indications or parameters of a frequency channel on which the WTRU may perform one or more measurements (e.g., requested or enabled measurements). The indications and / or parameters may include one or more of the following: a carrier or center frequency (which may be represented by EARFCN, for example), a bandwidth, and / or an identifier or index of a frequency channel that may be included in a configuration of a frequency channel (e.g., a configured list). The configuration may identify the carrier frequency and / or bandwidth and / or other parameters of the channel.

[0133] Measurements may be used to represent a single or specific measurement and / or a combination of one or more measurements of the same or different types. The combination results in a single value that can be reported. The measurement indication or other request or indication may provide resources, such as UL resources (e.g., on a PCell, on an LAA cell for the requested or indicated measurement or one or more measurement-related signals, or on another cell) on which the WTRU may report the requested or indicated measurement or other values ​​associated with or determined from the requested or indicated measurement or one or more measurement-related signals.

[0134] The eNodeB may request the WTRU to report the measurement results, and / or the WTRU may use UL resources (e.g., PUCCH and / or PUSCH resources) to report the measurement results, where the UL resources may be provided by the eNodeB with a measurement indication or request. The WTRU may report the measurement results when the UL resources are provided for this purpose or for another purpose (e.g., at a later time).

[0135] For UL resources that can be provided and / or used for measurement reports (e.g., LAA measurement reports), the resources can be resources (e.g., PUCCH and / or PUSCH) on a cell in an authorized spectrum (e.g., a PCell or another cell). For UL resources that can be provided and / or used for measurement reports (e.g., LAA measurement reports), the resources can be resources (e.g., PUCCH and / or PUSCH) on a cell in an unlicensed spectrum (e.g., a LAA cell or another cell that can be applied for measurement indications, requests, or reports).

[0136] The WTRU may report measurements according to a schedule that may be configured and / or based on a triggering event (eg, a measurement crossing a threshold or a change in a measurement crossing a threshold).

[0137] Figure 4 400 is a signal diagram of an example method of a channel measurement and reporting mechanism for long term evolution (LTE) operation in an unlicensed band. The WTRU may take or perform one or more measurements. Further, the WTRU may report the measurement results, and may report the measurement results if the measurement results exceed (or meet) a threshold, or report the fact that the measurement results exceed (or meet) a threshold. The WTRU may receive dynamic signals and / or interference measurement requests from an eNodeB, and may report back the usage of the LAA (or unlicensed band) cell to the eNodeB. In the example shown in signal diagram 400, an eNodeB 401 and a WTRU 402 share the use of an LAA channel with another user of the LAA channel. The channel may initially be used by other users 420, and then enter an idle period 430. After the idle period, the eNodeB 401 and the WTRU 402 may begin using the channel 440. The eNodeB 401 and the WTRU 402 may be part of an LAA cell. In one example, the LAA cell may indicate a subframe (or possible window of subframes) and / or time / frequency resources for taking or performing measurements. For example, the eNodeB 401 may send a measurement request 450 to the WTRU 402 requesting the WTRU 402 to take or perform measurements. In one example, the measurement request 450 may be included in a downlink grant from the eNodeB 401 to the WTRU 402. The measurement request may include an indication of time and / or time / frequency resources for measuring reference signals or interference in an unlicensed band. The resources may correspond to CSI-RS, zero power (ZPR) CSI-RS, CSI-IM, RE sets and / or subcarrier sets, etc.

[0138] In one example, the WTRU 402 may receive data and make a first measurement in subframe (SF) n 460. The WTRU 402 may also make a second measurement in SF n+1 and may make a third measurement in SF n+2. The WTRU 402 may then report the measurement results 490 back to the eNodeB 401.

[0139] In one example, in addition to the measurement result, the report 490 transmitted by the WTRU 402 may also indicate a time indication and / or a subframe (or subframe window) and / or a resource associated with the measurement result (e.g., when the measurement result occurred and / or the measurement result exceeded a threshold). The time indication may be at least one of the following: a timestamp (absolute or relative to the request), a time window (e.g., a start and stop time), or a time amount (e.g., a number of SFs, a time resource, or a symbol).

[0140] In one example, for example, the WTRU may send a measurement report to an eNodeB or cell. The measurement report may include one or more of the following: the measurement value or a typical value of the measurement; an indication of a time (e.g., a timestamp or time window) and / or an amount of time during which the measurement result or other value may be evaluated; an indication of a time (e.g., a timestamp or time window) and / or an amount of time during which the measurement result or other value meets or exceeds a certain criterion; an indication of the time at which the measurement evaluation was started; a cell ID corresponding to the measurement (e.g., a cell ID of an LAA cell); a frequency or frequency channel information (e.g., a carrier frequency) of a channel corresponding to the measurement; and a channel resource (in time and / or frequency) to which the measurement was performed and / or to which the report corresponds.

[0141] The time indication may be absolute, such as the SFN, or may be relative, such as an offset from a start time (e.g. in a subframe), where the start time may be the subframe in which the measurement indication is transmitted or received. The indication of time and / or amount of time may be a time window, such as a measurement period. The time window may have a start time and / or a duration. One or more of the start time and / or duration may be known and need not be included in the report. For example, the start time may be the subframe n in which the measurement request is transmitted and / or received, or a subframe offset k relative to subframe n (e.g. k=4). The indication of time and / or amount of time may be the number of time periods (e.g. the number of symbols or subframes). The indication of the time and / or amount of time that a measurement result or other value meets or exceeds a threshold may be the number of time periods, or may be a ratio or percentage of time relative to the time at which the measurement result or other value is evaluated.

[0142] In one example, the evaluation time window may be N time periods (e.g., subframes), and in the N time periods, the measurement result will meet the criterion (e.g., in K subframes) K times (e.g., above or below a threshold). One or more of N, K, and K / N may be reported.

[0143] Actual values, quantized values, indices representing the values ​​or quantized values, indices of configuration sets, or other representations of values ​​to be reported may be used here and still be consistent with the present disclosure. Measurement results or typical values ​​may correspond to maximum values, average values, and / or filtered values ​​(e.g., averaged or filtered by a higher layer).

[0144] The indication of the time and / or amount of time in the report may help the eNodeB determine the presence of a hidden node. For example, if the WTRU may generate and report interference measurements at a certain time period (e.g., on a certain frequency channel), and the eNodeB does not detect interference, the eNodeB may use this information to learn about interference that it does not see, which may be from a hidden node.

[0145] Figure 5 5 is a system diagram of an example wireless system including hidden nodes. As shown in system 500, WTRU 502 may communicate with node 510 and may be within the transmission range 515 (e.g., coverage area) of node 510. WTRU 502 may receive information (e.g., desired signal) from node 510. The WTRU 502 may also be within the transmission range 525 (e.g., coverage area) of node 520, thereby, the WTRU 502 may receive one or more interfering signals (e.g., interference) from node 520. However, since node 510 is outside the transmission range 525 (e.g., coverage area) of node 520, it does not detect the presence of node 520. In this case, WTRU 502 may measure interference from node 520, may detect the presence of node 520, and may report these measurements to node 510. As a result, node 510 may be aware of the presence of node 520 (e.g., hidden node (from the perspective of node 510)). And one or more of its own transmissions may be adjusted accordingly.

[0146] The measurement results may help the eNodeB select an appropriate channel and / or SCell to assign to the WT GRU, thereby enabling more efficient use of the LAA channels. Such measurements may (or may also) allow the eNodeB to switch between LAA channels, for example, assigned to a WTRU that can make more efficient use of the LAA channels. As an example, such measurements may (or may also) allow the eNodeB to switch between LAA channels quickly (e.g., at each active time period).

[0147] The WTRU may observe and / or measure a channel and / or one or more measurement-related signals, and / or may report one or more reporting parameters and / or measurement types, for example, to its serving eNodeB or cell (e.g., its PCell), or via its PCell.

[0148] Report parameter, measurement parameter and measurement type are used interchangeably. Report, measurement report, measurement feedback report and feedback report are used interchangeably.

[0149] As an example, the WTRU may dynamically implicitly and / or explicitly receive measurement indications for one or more reporting parameters.The WTRU may receive and / or apply separate or different measurement indications for separate or different reporting parameters.

[0150] As an example, in a measurement report or as part of a reporting mechanism, the WTRU may include one or more reporting parameters and / or measurement types and / or an indication of the channel resources for which the (or each) parameter and / or measurement type was calculated.

[0151] As an example, the eNodeB may dynamically configure and / or request the WTRU to perform or make measurements. The configuration and / or request may indicate to the WTRU a set of channel resources (e.g., subframes and / or PRBs) available for it to perform measurements. The WTRU may be configured and / or provided with a set of measurement types to be performed using the resources. The WTRU may perform one or more of the configured and / or provided measurement types using some or all of the indicated channel resources.

[0152] In the measurement feedback report, the WTRU may indicate the measurement types that may be included and / or the set or subset of resources used for the measurement (e.g., a subset of channel resources configured or indicated by the eNodeB). The set or subset of resources may be indicated as an index (e.g., indicated to the eNodeB). As an example, the WTRU may report the subframes or time periods for which reporting parameters (e.g., CQI, PMI, RI, CSI-RS related parameters or measurement results (e.g., RSRP, RSRQ, RSSI, eRSSI, interference, SNR, and SINR, etc.)) have been measured and / or calculated. The subframe may be identified by one or more indexes (e.g., one or more exact or absolute indexes of the subframe).

[0153] The WTRU may perform measurements in or using channel resources by looking for or measuring specific measurement-related signals or characteristics of measurement-related signals. The WTRU may report one or more of the following (e.g., for measurement-related signals): received signal strength, received interference level, received total energy and / or power, and received noise power, etc.

[0154] The WTRU may perform measurements in, using, or on channel resources regardless of whether the resources contain (expected, expected, or predetermined) measurement signals.

[0155] The WTRU may report one or more of the following (eg, for a measurement process, a measurement signal, and / or a measurement channel): received signal strength, interference level, total received energy and / or power, and noise power, among others.

[0156] For a WTRU configured with measurements (and / or requested to perform measurements) on one or more LAA channels and / or LAA cells or SCell cells, the WTRU may report or feedback measurement results regarding one or more (e.g., any) of the measurement types and / or parameters described herein. The report or feedback may be provided or transmitted by the WTRU on the WTRU's PCell and / or its one or more SCells and / or LTE-U SCell. The feedback or report may be one or more of the following: periodic, on-demand, scheduled, enabled and / or disabled, activated and / or deactivated, and / or triggered by an event.

[0157] The WTRU may be configured with reporting occasions. This configuration may be included with the configuration of the measurement type to which the occasion applies. The reporting occasion may be subject to one or more of the following: activation / deactivation, enable / disable, start / stop, and / or on-demand request.

[0158] The WTRU may be configured to have LAA channel measurement gaps. As an example, the measurement gaps may be dynamically configured so that the WTRU's measurements reflect the usage of the LAA channel, which may be uneven.

[0159] The WTRU may perform measurements on one or more LAA channels and / or LAA cells (e.g., in a non-periodic manner and / or when triggered by its serving eNodeB or cell (e.g., PCell)). For example, the WTRU may be configured or pre-configured (and / or receive measurement indications) for one or more measurement types and may perform measurements of one or more of these measurement types (e.g., autonomously and / or when requested). The WTRU may report some or all measurement results, for example, upon receiving a request for measurement result feedback from an eNodeB (or in response to the request).

[0160] As an example, UL resources may be granted to the WTRU in a scheduling grant or in a measurement feedback request. These resources may be granted in a DCI format provided by means of an (E)PDCCH transmission from a PCell. The WTRU may report in the granted UL resources the measurements it makes (or performs) on one or more LAA channels and / or LAA cells or SCells.

[0161] For example, the WTRU may be semi-statically configured to have multiple LAA channels and / or LAA cell sets available for it to perform measurements. These sets may include or exclude LAA cells and / or channels activated for the WTRU. These sets may include or exclude LAA cells configured to act as serving cells for the WTRU. Sets of LAA channels and / or LAA cells may be configured to have specific time and / or frequency resources at which measurements can be performed. In one example, the time available for the WTRU to perform measurements on some LAA channels and / or cells (e.g., one or more channels and / or cells that are not configured and / or activated for the WTRU) may be configured as measurement gaps. In one example, an LAA channel and / or cell set may be assigned an index. In another example, each LAA channel and / or cell set may be assigned an index.

[0162] The DCI that may be transmitted to the WTRU may provide a measurement indication to the WTRU. The measurement indication may be or may include a LAA measurement request and / or a measurement report request. The indication may be in the form of an information element or a bit string, where in one example, the information element may be a new information element. The indication (e.g., a code point of a bit string) may request or instruct the WTRU to perform at least one measurement-related operation.

[0163] As an example, the measurement indication may request (or indicate to) the WTRU to perform measurements on at least one or more (or in one example, each) channels and / or cells in a set of LAA channels and / or cells. The set may be indicated by an index included with the measurement indication.

[0164] In another example, the measurement indication may request (or indicate to) the WTRU to report at least measurement results for one or more (or in one example, each) channels and / or cells in a set of LAA channels and / or cells. The set may be indicated by an index included with the measurement indication. The request (or indication) for a measurement report may include or imply that the WTRU perform the associated one or more measurements.

[0165] In a further example, the measurement indication may request (or indicate to) the WTRU to report at least measurement results for each channel and / or cell in the set of LAA channels and / or cells, where the measurement results are above or below a threshold. As an example, the number of channels and / or cells for which measurement results may be reported in a report may be limited to M, where M may be configured by the eNodeB, known, or determined by the WTRU.

[0166] In an additional example, feedback resources (e.g., feedback resources for the WTRU to use for measurement reporting) may be included (e.g., identified or granted) in the DCI. These resources may be pre-configured and may be selected or identified in the DCI, for example, by an index or other identifier included in the DCI. The resources may be time and / or frequency resources and may be in at least one subframe for performing measurements in an unlicensed band.

[0167] The WTRU may then perform measurements in accordance with the request and may send a report to the eNodeB based on the measurements performed. In a further example, the at least one subframe used to perform the measurements may be the requested subframe or a subframe window starting with the requested subframe. In another example, the measurement report may include an identification of a subframe or system frame number (SFN) associated with the measurement. In yet another example, the measurement report may be sent in a licensed and / or unlicensed frequency band.

[0168] In another example, the measurement indication may request (or indicate to) the WTRU to delete all measurements previously made for the LAA channel and / or cell set. This can control the measurement filtering process.

[0169] In a further example, a measurement indication regarding an LAA channel and / or a set of cells may request or imply that the WTRU delete all measurements previously made for that LAA channel and / or a set of cells. For example, any measurement indication regarding an LAA channel and / or a set of cells may request or imply that the WTRU delete all measurements previously made for that LAA channel and / or a set of cells. The measurement indication may request (or indicate to the WTRU) to begin event-based measurement report triggering processing for the LAA channel and / or a set of cells.

[0170] In an additional example, the measurement indication may include or identify time and / or frequency resources (eg, REs and / or PRBs) used to perform the measurement. These resources may be considered as resources configured for the measurement.

[0171] A measurement indication for or corresponding to a set of LAA channels and / or cells may include an indication about the set. A set may be or may include a single LAA channel and / or LAA cell. The WTRU may receive a measurement indication in a DCI transmitted by an LAA channel and / or cell. The measurement indication may (e.g., implicitly) request a measurement result or measurement report about the LAA channel and / or cell.

[0172] The eNodeB may provide a measurement indication with the aid of the WTRU's serving cell (e.g., the WTRU's PCell, LAA Scell, or non-LAA Scell). Upon receiving or responding to a measurement indication, the WTRU may perform measurements, report measurement results, and / or delete measurement results in accordance with the indication.

[0173] Once configured and / or requested to perform and / or report LAA measurements (e.g., via an LAA measurement indication) (either thereafter or in response thereto), the WTRU may perform measurements on appropriate time and / or frequency resources. For example, the WTRU may measure the total energy contained in the configured or identified set of REs and may average it over the entire bandwidth of the symbol. In another solution, the WTRU may calculate the sum of the total energy in the configured or identified time and / or frequency resources. The WTRU may also be configured with filters to better assess interference. As an example, the WTRU may be configured with a filter for averaging measurements (e.g., 3 measurements within 200 milliseconds) over multiple OFDM symbols (possibly over a specific time period). If the measurements are performed using new valid time and / or frequency resources, the measurements may be updated based on a sliding window. The WTRU may be configured with reporting thresholds (e.g., for the WTRU to perform event-driven reporting). Examples of thresholds that trigger feedback of measurement results include at least one of the following: a minimum (or maximum) value that has been achieved, an offset change in the value observed at adjacent measurement times, and a measured offset difference between two LAA channels and / or cells (for example, the offset difference between the measuring cell and the serving cell).

[0174] When reporting measurement results, the WTRU may be configured with a table for mapping measurement ranges to reporting code points. The WTRU may be configured with multiple tables, or a subset of the reporting tables may be provided dynamically or semi-statically. This enables different measurement reporting granularities.

[0175] In a request for measurement feedback (e.g., a request for a measurement report), the eNodeB may indicate to the WTRU the measurement types (e.g., to be measured and / or reported) and may indicate the associated measurement configuration. For example, the WTRU may receive a measurement or other indication or request (e.g., in a DCI) that may include information about the measurement types to be performed and / or reported and / or resources on which the measurements may be made (or performed). The WTRU may measure and / or report to the eNodeB the indicated one or more measurement types, e.g., in a request for feedback (e.g., a report) or in future granted resources.

[0176] The dynamically indicated resources available for the WTRU to perform measurements may be considered as non-periodic measurement gaps available for the WTRU to perform multiple measurements. The eNodeB may configure the WTRU with a time period during which it may perform measurements. A WTRU configured with a set of resources (e.g., subframes and / or PRBs) may perform measurements on a subset of the resource set. For example, the WTRU may be configured with multiple subframes for performing measurements. The WTRU may perform a first measurement on a first subset of subframes and a second measurement on a second subset of subframes (as an example, the second measurement may be of the same type as the first measurement). The WTRU may be configured to report multiple measurement results, where the report may include one or more measurement results and / or a subset of resources used to perform one or more measurements. These measurement types may include one or more of the measurement types described herein.

[0177] The WTRU may perform averaging in the time domain and / or frequency domain for measurement parameters observed on multiple channel resources, where the channel resources may be in or indicated by the measurement indication.

[0178] The WTRU may be configured and / or implicitly and / or explicitly receive a parameter that may describe and / or include an averaging window that may be in the time domain and / or frequency domain. In the averaging process, the WTRU may (or may only) consider channel resources that are within the limits of the averaging window.

[0179] For example, the WTRU may calculate the average interference that it may observe or measure in a certain number (e.g., 24) of REs (e.g., the center REs), where the REs may be in a particular OFDM symbol, such as in every odd-numbered OFDM symbol (this may be indicated as part of a measurement indication with an OFDM symbol repeating pattern of "01"). The WTRU may receive a time averaging window length having a certain number (e.g., 4) of OFDM symbols. As an example, when averaging the interference, the WTRU may (or may only) consider the indicated OFDM symbols in the indicated time window. For example, when averaging the interference level for the center 24 REs, since there are only two odd-numbered OFDM symbols in the period of 4 OFDM symbols, the WTRU may (or may only) consider 2 odd-numbered OFDM symbols.

[0180] The WTRU may (or may only) use for the measurement the channel resources that are within the averaging window and indicated in the associated measurement indication. The averaging window may be described in the frequency domain and / or the time domain. The averaging window may be defined by its OFDM symbol length (e.g., 4) and the number of subcarriers (e.g., 24).

[0181] The WTRU may take an average of the measured parameter over a specific time frame. The WTRU may report the average to the eNodeB as part of the measurement report.

[0182] When triggered (eg, by an event based on a measurement value or a change in a measurement value), the WTRU may report measurement results or measurement parameters for one or more measurement types.

[0183] The timing for event-triggered measurement report processing may be preconfigured. For example, the WTRU may be configured to have resources available for use when a measurement report is triggered. In another example, the WTRU may indicate in the UL Scheduling Request message that the purpose of the UL transmission is to report event-triggered measurement results.

[0184] Events that can trigger measurement reports can be configured, for example, according to measurements and / or according to LAA channels. For example, on a first LAA channel, an interference measurement result with a certain level or value can trigger (or be configured to trigger) a report processing on the measurement (or event), while on a second LAA channel, the same interference measurement result level or value will not trigger (or will not be configured to trigger) a report on the measurement (or event).

[0185] A first measurement event that may trigger a report about a first measurement may (or may also) trigger or cause a report about a second measurement. For example, interference measured on a first LAA channel may trigger a report about the measurement (or event) and may (or may also) trigger or cause a report about one or more other interference measurements that may be made in one or more other configurable LAA channels.

[0186] As another example, an interference measurement made on an LAA channel may trigger reporting of that measurement as well as other types of measurements (e.g., eRSSI) on the same LAA channel. The measurement that triggers reporting may not necessarily be the measurement to be reported.

[0187] In response to an event associated with a measurement (e.g., a measurement type described herein), the WTRU may transmit a report or measurement report, such as to an eNode B. The event may or may be considered to trigger the report.

[0188] One or more events may trigger one or more measurements and / or one or more reports. An event that may trigger a measurement and / or report may be the receipt of a measurement indication, wherein the measurement indication may include a grant regarding UL resources for transmitting the report. An event that may trigger a measurement and / or report may be the receipt of an UL resource grant (e.g., an aperiodic grant) provided by an eNodeB for reporting measurement results. The UL grant may include an indication of channel resources available for the WTRU to perform measurements. The UL grant may include or indicate UL resources that should be used by the WTRU to report such measurement results.

[0189] When a measurement is likely to be (or is likely to become) greater than (or less than) a configurable (or configured) threshold, a report may be triggered. A report may be triggered if a measurement in one occasion (or set of occasions) has a drift that is (or is likely to become) greater than (or less than) a measurement in another occasion (or set of occasions) (e.g., of the same type), where the measurement in the other occasion (or set of occasions) may or may not have been previously reported. For example, the WTRU may report a measurement type and may (or may only) report the measurement type again if the measurement type increases (or decreases) by a certain threshold since the last time it was reported.

[0190] A report may be triggered when the offset of a measurement type is likely to be (or is likely to become) greater than (or less than) the offset of a measurement or measurement type made on another LAA channel. For example, if the offset of the measured value is greater than the value of a second (e.g., reported) measurement result on a second LAA channel, then the WTRU may report the measurement result on the first LAA channel.

[0191] A report may be triggered when a measurement result is likely to be (or is likely to become) greater than or less than a configurable (or configured) threshold, such as being greater than or less than a configurable (or configured) threshold for a configurable (or configured) number of times (e.g., a consecutive number of times) for a configurable (or configured) duration. For example, the WTRU may be dynamically configured with a set of resources on which it may perform measurements (e.g., RSSI or eRSSI) on an LAA channel. If more than a configured number of individual measurements (each of which may be measured on a subset of resources within a resource set) exceed the configured threshold, the WTRU may report one or more measurement values ​​and / or an indication that the condition has been met. Doing so enables the eNodeB to determine one or more parameters of the traffic in a LAA channel that may be non-uniform.

[0192] An event that may trigger a report may be a trigger on RSRP and / or RSRQ. A report corresponding to a trigger on RSRP and / or RSRQ on an LAA channel may (or may also) include one or more of the following: RSRP, RSRQ, RSSI or eRSSI, interference, SINR, and / or radar detection measurements. For example, if a WTRU may be triggered to report RSRP on an LAASCell, the WTRU may also include RSSI or eRSSI on an LAA channel on which the LAASCell may operate.

[0193] The WTRU may be configured (e.g., dynamically) with a set of resources on which it may perform multiple measurements, where the measurements may be of the same type and / or may be performed on subsets (e.g., different subsets) of the set of resources. One or more (e.g., any) of these measurements may trigger a measurement feedback report.

[0194] In a report triggered by a measurement, the WTRU may (and / or may be configured to) report one or more other measurement results. A measurement event regarding a measurement may trigger the WTRU to perform and / or report other measurements. For example, the WTRU may be configured to have a set of subframes on which to perform interference measurements. The WTRU may measure interference on a first subframe. Upon comparing it to a threshold (or based on the result of the comparison), the WTRU may be triggered to measure and / or report interference from one or more other subframes in the configured set of subframes.

[0195] The WTRU may report one or more interference measurement results to the eNodeB. The WTRU may include subframe information (e.g., subframe index) for each measurement result that it may report. The WTRU may (e.g., first) request UL resources for transmitting the report. The WTRU may transmit the report in UL resources that it obtains from the eNodeB using a measurement request (e.g., a dynamic measurement request).

[0196] In one example, a WTRU may monitor the interference level in a currently configured LTE-U SCell, where the WTRU may be configured with an associated threshold monitoring value. If the interference level of the channel is above the configured interference threshold, the WTRU may notify the eNodeB of the event. If the eNodeB receives a high interference report from one or more of its WTRUs, the eNodeB may change some parameters of the LTE-U SCell, such as the frequency channel.

[0197] In another example, the WTRU may monitor the received signal strength in the currently configured LTE-U SCell, where the WTRU may be configured with a threshold monitoring value. When the received signal strength level of the LTE-U SCell may be lower than the configured signal strength threshold, the WTRU may notify the eNodeB of the event. When the eNodeB may receive a low signal strength report from one or more of its WTRUs, the eNodeB may change some parameters of the LTE-U SCell, such as the frequency channel.

[0198] In another example, the WTRU may monitor (e.g., continuously) one or more (e.g., other) LTE-U cells and / or one or more (e.g., other) LTE-U frequency channels. When the measured parameters of the LTE-U cells and / or frequency channels are below and / or above a certain threshold, the WTRU may report the event and / or one or more characteristics of the one or more cells and / or channels to its eNodeB.

[0199] The eNodeB may use a measurement indication to request one or more WTRUs or configure one or more WTRUs to measure one or more LAA frequency channels. As an example, the WTRU may measure the interference level and / or total received power and / or other interference-related parameters in the channel resources indicated as part of the measurement indication in response to the measurement indication. The WTRU may report the interference level and / or one or more other indications of one or more frequency channels to the eNodeB. An example of another indication may be whether the interference level is above or below a threshold. Another example of another indication may be the cell ID of another LAA cell using the channel.

[0200] The eNodeB may use the reports it receives from one or more WTRUs to select a frequency channel, such as a frequency channel with the lowest detected interference level and / or total received power or the lowest average interference for some or all of its WTRUs. The eNodeB may use the reports it receives from one or more WTRUs to determine whether there are hidden nodes, and / or where the hidden nodes are located, and / or which WTRUs are near hidden nodes. As an example, the eNodeB may change the frequency channels and / or resources available for scheduling for one or more WTRUs in the LAA cell based on the reports it receives.

[0201] The WTRU may perform measurements on and / or provide reports related to its currently configured and / or activated LTE-U cell and / or one or more other LTE-U cells and / or candidate frequency channels.

[0202] In unlicensed spectrum, the users of the band may change frequently, and thus the interference environment may also change frequently. It would be very useful if the LAA cell could adapt to these changes, for example to improve performance.

[0203] In one example, the LAA cell may (e.g., dynamically) change and / or allocate different resources (e.g., time and / or frequency resources) to different channels and / or signals (e.g., channels and / or signals that may be used for measurement). Channels and / or signals that may be used for measurement may be referred to as measurement-related signals. Time and / or frequency resources may be referred to as channel resources.

[0204] For example, the LAA cell may transmit one or more channels and / or signals (eg, measurement-related signals), such as synchronization signals and / or CSI-RS signals, in channel resources that experience less interference than other channel resources.

[0205] LAA cells that can use channels simultaneously can place one or more of their measurement-related signals in different channel resources. As an example, the LAA cell can (e.g., in a dynamic manner) modify the time, location (e.g., frequency), and / or density (e.g., repetition density) of one or more channels and / or signals (e.g., measurement-related signals) to optimize the use of channel resources as needed.

[0206] The term time / frequency may be used to refer to time and / or frequency.

[0207] CSI reports for LAA cells may be provided and / or used here. The CSI reports may be aperiodic, on-demand and / or triggered. Aperiodic, on-demand and triggered may be used interchangeably. Reference signals, CSI-RS, CRS, DM-RS, DRS, measurement reference signals, reference resources for measurement, CSI-IM and measurement RS may be used interchangeably.

[0208] In one example, the location of the measurement reference signal for CSI measurement may be a specific time / frequency location in the LAA cell. For example, the time, frequency, or time / frequency location of the reference signal may be determined (e.g., by the WTRU) in accordance with at least one of the following: a subframe number that may trigger CSI (e.g., aperiodic CSI) measurement and / or reporting, a channel number in the LAA cell that the WTRU may (or may need to) measure CSI, a configurable transmission mode, a periodic reporting mode, and an (E)PDCCH candidate number from which the WTRU may receive or has received a CSI (e.g., aperiodic CSI) measurement and / or reporting trigger. As an example, the WTRU may perform CSI reporting, such as CQI, PMI, and / or RI reporting, in accordance with the configured transmission mode and by using the reference signal.

[0209] The reference signal may be a CSI-RS that may be transmitted within a subframe. The CSI-RS may be: a non-zero power CSI-RS for the WTRU to estimate the serving cell channel to measure the CSI; a zero power CSI-RS for the WTRU to perform rate matching around a PDSCH used for zero power CSI-RS resources (e.g., when a PDSCH may be scheduled for the WTRU or an EPDCCH may be monitored by the WTRU); a CSI-IM for the WTRU to measure interference; or one or more combinations of non-zero power CSI-RS, zero power CSI-RS, and CSI-IM.

[0210] The eNodeB may request or instruct the WTRU to report CSI (e.g., aperiodic CSI) associated with the LAA cell. In one example, the report (e.g., aperiodic report) may be triggered in subframe n, and the measurement reference signal may be located in subframe n+k. The measurement reference signal location may be determined according to the subframe number that may trigger the CSI report (e.g., aperiodic CSI report). As an example, the WTRU may report CSI (e.g., aperiodic CSI) in subframe n+k+s in or with the aid of the PCell. The CSI (e.g., aperiodic CSI) report trigger may be based on DCI transmitted with the aid of (E)PDCCH (e.g., in or by the PCell). k and / or s may be a number including 0 (e.g., a predefined number). k and / or s may be configured by higher layer signaling, or may be indicated in the DCI, for example, by an RNTI (e.g., C-RNTI or CSI-RNTI).

[0211] C-RNTI may be replaced with CSI-RNTI, or vice versa, and still be consistent with the present disclosure.

[0212] A DCI with a certain RNTI (e.g., CSI-RNTI) may be used to trigger a CSI (e.g., non-periodic CSI) report on a LAA cell. The RNTI may be a group RNTI. For example, a DCI with a CSI-RNTI may be transmitted in an (E)PDCCH search space (e.g., a common search space) in a PCell. A WTRU configured with an LAA cell may monitor a DCI with a CSI-RNTI in an (E)PDCCH search space (e.g., a common search space). If a WTRU may receive a DCI with a CSI-RNTI in subframe n, the WTRU may measure CSI in subframe n+k. The RNTI (e.g., CSI-RNTI) may be configured in a WTRU-specific manner, or may be configured, provided, or predefined in a cell-specific manner, wherein the RNTI may be a group RNTI.

[0213] DCI (e.g., DCI with CSI-RNTI) that can be used to trigger CSI reporting (e.g., non-periodic CSI reporting) may include one or more of the following: a subframe index or subframe offset indicating a subframe (or subframe number) that may contain a measurement reference signal in an LAA cell; configuration of a measurement reference signal (e.g., CSI-RS, but not limited to CSI-RS), which may include at least one of the following: CSI-RS reuse pattern, CSI-RS configuration index, number of antenna ports, CSI process number, physical or virtual cell ID for scrambling; SCell number or index (e.g., when multiple SCells can be used); and uplink resource information for CSI reporting (e.g., in a PCell). The DCI with CSI-RNTI may be located in (or only in) a subset of subframes.

[0214] DCI (e.g., DCI having other purposes besides triggering CSI reporting) can or may also be used to trigger CSI (e.g., non-periodic CSI) reporting on LAA cells. For example, DCI that can be used to provide DL grants (e.g., resources on LAA cells) can (or may also) be used to trigger CSI reporting processing (or may include the trigger), wherein the reporting processing may include measuring and / or reporting interference. The interference may be measured on resources (e.g., CSI-IM resources). These resources may be indicated in the DCI (e.g., explicitly or by reference configuration) or may be configured separately. The DCI may be or include a DL grant and / or UL grant for a serving cell of the WTRU, wherein the serving cell may be a PCell or SCell in an authorized or unauthorized band.

[0215] In response to receiving the trigger, the WTRU may perform and / or report the indicated or requested measurements. The WTRU may perform measurements on or using the indicated resources, which may be CSI-IM resources.

[0216] In another example, the location of the measurement reference signal used for CSI measurement may be a certain time / frequency position in the LAA cell. For example, the time, frequency, or time / frequency position of the reference signal may be indicated by means of control information, wherein the control information may trigger CSI (e.g., non-periodic) measurement and / or reporting. For a DCI that may (or may be used to) trigger CSI (e.g., non-periodic CSI) measurement and / or reporting (e.g., associated with an LAA cell), the DCI may include a measurement reference signal configuration. The configuration may include at least one of the following: a subframe index or subframe offset that may indicate a subframe (or subframe number) containing a measurement reference signal; a measurement reference signal reuse pattern; and a configuration regarding one or more zero-power CSI-RS, non-zero-power CSI-RS, and / or CSI-IM.

[0217] In another example, the measurement reference signal may be transmitted based on the time (or timing or time position) of one or more LAA resource bursts (e.g., in a non-periodic manner). The LAA resource burst may be at least one of the following: a time resource (e.g., a subframe) that may be allocated to the LAA cell (e.g., continuously or periodically), a time resource (e.g., a subframe) within a time window of the LAA cell, and / or a time resource (e.g., a subframe) that may be allocated to the WTRU. The allocatable time resources may be configured in the WTRU, for example, by an eNodeB. The configuration may be performed with the aid of a PCell.

[0218] The subframe containing the measurement reference signal can be determined according to at least one of the following: SFN number (for example, in PCell), a configurable period, a subframe offset that can be configured via higher layer signaling, and / or resource availability and / or allocation in the LAA cell.

[0219] The measurement reference signal may be located in one (or more) subframes of (e.g., each) LAA resource burst. In one example, the first subframe in (e.g., each) LAA resource burst may include the measurement reference signal. The nth subframe of (e.g., each) LAA resource burst may include the measurement reference signal, where n may be predefined or configured by a higher layer.

[0220] The measurement reference signal may be located in a subframe subset of a LAA resource burst. For example, a LAA resource burst located in a specific SFN may include a measurement reference signal.

[0221] Here, an indication may be provided and / or used for a LAA resource burst containing a measurement reference signal. The indication may be transmitted in the first time resource (e.g., the first subframe) of the LAA resource burst. The indication may also be transmitted in control signaling for conveying scheduling information for the LAA resource burst.

[0222] In another example, CSI (e.g., non-periodic CSI) measurements and / or reports may be triggered by a timer. For example, the timer may be set or configured by an eNodeB (e.g., in a WTRU). If the timer expires (e.g., returns to zero) and / or when the timer expires and / or after the timer expires, the WTRU may measure the CSI in a subframe (e.g., in a subframe that is closest (e.g., in time) to the measurement reference signal). One or more of the following may apply: the timer may be WTRU-specific, predetermined, or configured by means of higher layer signaling. For example, the timer may be determined by the WTRU according to WTRU mobility. For example, the timer may be suspended when the LAA cell is not active (e.g., in a closed state). When the LAA cell is active again, the timer may be resumed. When the timer expires or returns to zero, a report process (e.g., a non-periodic report process) may be immediately triggered (e.g., by the WTRU). When the timer expires or returns to zero, the LAA cell may not be active. When the timer expires or returns to zero, and / or when the LAA cell is not active (e.g., in an off state), a reporting process (e.g., aperiodic reporting process) will not be triggered (e.g., by the WTRU). As an example, the reporting process (e.g., aperiodic reporting process) may be suspended in the WTRU until the LAA cell is active again. As an example, the WTRU may start or restart the timer when (or after) the WTRU may report the measurement results.

[0223] In another example, as an example, the WTRU may use the PUCCH in the PCell to perform reporting processing (e.g., non-periodic reporting processing) regarding the LAA cell. For example, CSI reporting processing (e.g., non-periodic reporting processing) may be triggered for the LAA cell in subframe n, and as an example, a CSI report (e.g., non-periodic CSI report) regarding the LAA cell may be transmitted in subframe n+k+s with the help of the PUCCH in the PCell, where subframe n+k may contain a measurement reference signal. One or more of the following may apply here: a CSI reporting mode based on PUCCH (e.g., a PUCCH CQI feedback type) may be used for CSI reporting (e.g., non-periodic CSI reporting). For CSI reporting (e.g., non-periodic CSI reporting), a PUCCH-based CSI reporting mode (e.g., the mode may use PUCCH resources, as an example) may be used for LAA cells, and / or a PUSCH-based CSI report (e.g., the report may use PUSCH resources, as an example) may be used for PCell. A subset of PUCCH-based CSI reporting modes may (or may only) be used as CSI reporting (e.g., aperiodic CSI reporting) modes for LAA cells. For example, wideband PMI / CQI / RI reporting modes (e.g., mode 1-0 and mode 1-1) may (or may only) be used for aperiodic CSI reporting. PUCCH resources in the PCell for reporting (e.g., aperiodic reporting) may be configured via higher layer signaling in a WTRU-specific manner.

[0224] The PUCCH resource may be indicated in the associated DCI that may be used for a report (e.g., an aperiodic report) trigger. The PUCCH resource may be determined according to the PUCCH resource index in the associated DCI. The starting (E)CCE number of the (E)PDCCH containing the report (e.g., an aperiodic report) trigger may be used to indicate the PUCCH resource index for the CSI (e.g., an aperiodic CSI) report.

[0225] The LAA cell may use one or more (e.g., two) types of CSI reporting (e.g., aperiodic CSI reporting) modes. For example, the CSI reporting (e.g., aperiodic CSI reporting) mode based on PUCCH (e.g., PUCCH CQI feedback type) and / or the CSI reporting (e.g., aperiodic CSI reporting) mode based on PUSCH (e.g., PUSCH CQI feedback type) may be used.

[0226] The CQI feedback type may be determined based on a timer. For example, if the timer expires, then the PUCCH CQI feedback type may be used, otherwise the PUSCH CQI feedback type may be used, and vice versa. The CQI feedback type may be configured by the eNodeB, for example, by means of higher layer signaling. If and / or when a CSI report may be triggered (e.g., an aperiodic CSI report), the CQI feedback type may be based on the configuration provided by the higher layer signaling. Alternatively, the CQI feedback type may also be indicated dynamically, for example, in the associated DCI that triggers the processing for the CSI report (e.g., an aperiodic CSI report).

[0227] The CQI feedback type may be indicated by defining one or more (e.g., two) RNTIs, where the RNTI may be a group RNTI. As an example, aCSI-RNTI and pCSI-RNTI may be defined. aCSI-RNTI may be used to indicate the PUSCH CQI feedback type, and pCSI-RNTI may be used to indicate the PUCCH CQI feedback type.

[0228] The interference measurement report provided and / or used may be aperiodic, on-demand, and / or triggered. Aperiodic, on-demand, and triggered may be used interchangeably. Interference measurement, interference level report, measured interference, interference signal strength, signal power in an interference measurement reference signal, and CSI-IM measurement results may be used interchangeably.

[0229] In one example, the WTRU may be requested or instructed (e.g., by an eNodeB) to measure the interference level in a certain time / frequency resource (or multiple resources). The time / frequency resource (or resources) used for interference measurement may be or may include a measurement reference signal that may be located in a subframe. The interference measurement may be performed using a measurement reference signal within a subframe. The interference measurement reference signal (IM-RS) may be at least one of a CSI-IM, a CSI-RS, a zero-power CSI-RS, and a CRS.

[0230] Configuration information about the IM-RS may be provided to a WTRU that is requested (or instructed) to use the IM-RS to measure interference levels. The configuration may be provided by an eNodeB. For example, a DCI may be used to trigger an interference level report, and the IM-RS configuration may be transmitted in the DCI. The IM-RS configuration may include at least one of the following: a reference signal pattern and / or reuse pattern; a scrambling code; a power allocation; and a subframe position and / or numbering.

[0231] The DCI may be received in a PCell (or LAA cell), and the IM-RS may be located in the LAA cell. An interference measurement trigger bit field may be defined in the DCI, where the field may be an independent bit field from a CSI (e.g., aperiodic CSI) report trigger field. The DCI (e.g., with a C-RNTI) may include a reference signal configuration for interference measurement. The DCI that may be used for PDSCH scheduling in an LAA cell may include a reference signal configuration for interference measurement. An RNTI (e.g., an interference measurement RNTI such as an IM-RNTI) may be used to trigger interference measurements on one or more (e.g., a group of) WTRUs, where the RNTI may be a group RNTI.

[0232] The IM-RS configuration may be determined according to at least one of the following: a subframe number that may trigger an interference level report, an (E)PDCCH candidate number that may trigger a DCI and the DCI may trigger an interference level report, and a physical or virtual cell ID of the LAA cell. The subframe (or subframe number) that may contain the IM-RS may be determined according to the subframe (or subframe number) that may trigger an interference level report. The WTRU may monitor one or more (e.g., multiple) (E)PDCCH candidates, and the IM-RS configuration may be determined according to the (E)PDCCH candidate that triggers the interference level report.

[0233] The WTRU may report the measured interference level in a certain subframe (e.g., in the PCell). The subframe for the measured interference level report may be determined by one or more of the following. The subframe for the interference level report may be determined according to the temporal position of the subframe containing the associated IM-RS. For example, if the associated IM-RS is located in subframe n, then the WTRU may report the measured interference level in subframe n+k, where n and k may be positive integers.

[0234] The subframe used for interference level reporting may be determined according to the temporal position of the subframe that triggers the interference level reporting. For example, if interference level reporting may be triggered in subframe n, then the WTRU may report the measured interference level in subframe n+k, where n and k may be positive integers.

[0235] As an example, in response to a measurement request, interference (e.g., IM-RS) measurements and / or reports may be conditioned on one or more factors indicated by an eNodeB (e.g., the eNodeB requesting the measurement and / or report) and / or determined by the WTRU. The one or more factors may include at least whether the LAA cell or channel on which the measurement is to be performed and / or reported is in an active state or within an active time (e.g., relative to the WTRU's serving eNodeB). The active time (e.g., the start, duration, and / or end of the active time) may be indicated by the eNodeB (e.g., in accordance with one or more embodiments described herein). The active time may be determined by the WTRU based on the indication or by blindly detecting the presence of one or more signals (e.g., a synchronization or busy signal).

[0236] As an example, if the WTRU is requested to perform interference measurements in a time resource (e.g., one or more subframes, time slots, or symbols) of a LAA cell, the WTRU may first determine (e.g., before or before the start of the time resource) whether the LAA cell (e.g., relative to the WTRU's serving eNode B) is in active time (and / or will be in active time when the measurement is performed).

[0237] If it is determined that the LAA cell is in (or not in) active time and / or will be in (or not in) active time when the measurement is performed, then the WTRU can (or can) perform the requested measurement and / or report the requested measurement. The active time relative to the eNodeB may refer to or correspond to the time when the eNodeB has an LAA channel and / or can perform transmissions on the LAA channel. When the one or more factors based on which the measurement and / or reporting are performed are established, the IM-RS resources associated with the measurement and / or reporting may be considered or determined to be valid.

[0238] The WTRU may send an interference report when one or more of the following applies: applicable IM-RS resources are determined to be valid, a timer (e.g., started at the last report) has expired, a report trigger has been achieved, and / or valid reporting resources are available. Reporting resources may be considered valid (or determined to be valid) if at least one of the following conditions occurs: the WTRU has successfully acquired an unlicensed channel on which to transmit the measurement report, the WTRU has been configured with resources in another cell that it can use to transmit the report, and the reporting resources have not been preempted for other reasons (e.g., transmitting a higher priority UL signal or channel).

[0239] In one example, separate (e.g., different) transmission time interval (TTI) lengths may be used for one cell (e.g., PCell) and another cell, wherein the other cell may be an SCell, an LAA cell, and / or an LAASCell. PCell may be used as a non-limiting example of the one or first cell. SCell may be used as a non-limiting example of the other cell.

[0240] As an example, in PCell, TTI can be defined as 1 millisecond, while TTI for SCell can be shorter than 1 millisecond. One or more of the following can be applied here. TTI for SCell can be defined as a relatively small number of OFDM symbols compared to the number of OFDM symbols for TTI in PCell. In an example, TTI in PCell can contain 14 OFDM symbols with normal CP, while TTI in SCell can contain 2 OFDM symbols with normal CP. Radio frame (for example, for SCell) can be defined as 1 millisecond and have 7 subframes (as an example, each of which has two OFDM symbols). In TDD, radio frame (for example, for SCell) can be defined as 1 millisecond and have 7 subframes (as an example, each of which can have 2 OFDM symbols), wherein the subframe can be used as or defined as uplink and / or downlink subframe.

[0241] The WTRU may report CSI based on a shorter TTI length, and the CSI reporting time (eg, latency) may be reduced.

[0242] SCell can use a wider subcarrier spacing, and doing so can shorten the OFDM symbol length. For example, PCell can use a 15kHz subcarrier spacing, while SCell can use a 150kHz subcarrier spacing. The TTI of PCell can be defined as 1 millisecond, while the TTI of SCell can be defined as 0.1 millisecond.

[0243] The reference resources that may be used for measurements may use (or may be assumed to use) a shortened TTI. For example, the reference resources used to perform measurements may be provided or indicated to the WTRU in the first shortened TTI opportunity (e.g., OFDM symbol n). The location (e.g., time location) of the reference resources may be (or may depend on) the symbol in which the indication is located, or may be received k OFDM symbols (where k may be or may be set to 0).

[0244] In one example, the reference resources may include a plurality of symbols starting at symbol k. Feedback may be reported in OFDM symbol n+k+s. For example, the WTRU may be configured to have measurements on the CRS and may be requested or instructed to perform measurements in the first symbol of a subframe (e.g., symbol 0). The reference resources for such measurements may be in symbols 4 to 8 (e.g., k=4), and the feedback resources on the PCell may be included in the second subframe (e.g., symbols 14 to 27 or k+s=14).

[0245] In another example, for example, if the CSI is out of date, then the processing time of the CSI measurement can be shortened. For example, one or more (e.g., two) CSI report types can be used here. One CSI report can use a conventional CSI measurement that may have a processing time of k subframes. Another CSI report can use a simplified CSI measurement with a processing time of s subframes, where k can be greater than s.

[0246] One or more of the following may apply: Type A CSI and Type B CSI. Type A CSI reports may have k subframe processing time. If a CSI report may be triggered in subframe n (e.g., aperiodic CSI reporting), the WTRU may report the corresponding CSI feedback in subframe n+k. In one example, for FDD, k may be equal to 4. As an example, in this case, the WTRU may (or may need to) perform a full CSI measurement.

[0247] A CSI report of type B may have a processing time of s subframes less than k. If a CSI report may be triggered in subframe n (e.g., a non-periodic CSI report), the WTRU may report the corresponding CSI feedback in subframe n+s. As an example, in this case (e.g., for a CSI report of type B), the WTRU may perform local CSI measurements. A subset of the CQI may be used. A subset of the codebook may also be used. In addition, a subset of the rank may be used. And a predefined CQI feedback type may also be used. Alternatively, the WTRU may use (e.g., only use) wideband CQI / PMI / RI to perform CSI measurements. In one example, s may be equal to 1.

[0248] Measurement types that may support eNodeB decisions (e.g., LAA channel segments) may be provided and / or used herein. One or more measurement types may enable the eNodeB to determine appropriate LAA channels and / or LAASCells for one or more WTRUs.

[0249] The eNodeB may use one or more measurement types described in one or more embodiments and / or examples herein to determine (e.g., appropriate) LAA channels and / or LAA SCells for one or more WTRUs.

[0250] For one or more (e.g., any) of the measurement types described herein, the trigger (e.g., for the WTRU) to start the measurement process may be a measurement configuration made by or from the eNodeB (e.g., received by the WTRU). When configured by the eNodeB, there is no need to continuously monitor the measurement results. Measurements and / or reporting may be triggered dynamically, aperiodically, and / or on demand.

[0251] The WTRU may be configured to report measurements similar to RSSI (Received Signal Strength Indicator). The RSSI-like measurements may be LTE RSSI measurements. The WTRU may be configured to perform and report RSSI measurements for one or more LAA channels. Reporting of RSSI measurements may be independent of reporting of RSRP and / or RSRQ.

[0252] A measurement similar to RSSI may be an enhanced RSSI (e.g., eRSSI) measurement, and may include a linear average of the observed total received power (e.g., over a configurable (or configured) amount of time and / or over a configurable (or configured) bandwidth). For the configuration of the eRSSI measurement performed by the eNodeB, the configuration may include a bandwidth for performing (or executing) the measurement and / or a duration for the measurement. In one example, the duration may be configured in units of LTE OFDM symbols. In another example, the duration of the eRSSI measurement may be a sub-LTE OFDM symbol length. For example, the eRSSI may be configured by a WTRU OFDM symbol length. The eRSSI measurement timing may be synchronized with one of the WTRU serving cells (e.g., its timing). In another example, the configuration of the eRSSI may include a timing offset (e.g., microseconds) relative to the timing of one of the WTRU's serving cells.

[0253] The WTRU may be configured to perform interference measurements on one or more LAA channels or cells. The WTRU may be provided with resources on which it can measure interference. For example, the WTRU may be configured to have a set of REs and / or subframes on which it can perform measurements. If the WTRU has a serving cell on an LAA channel and the WTRU may be configured to perform interference measurements on it, then the WTRU may assume that its serving cell has no transmissions in the resources configured for interference measurements, at least not for the WTRU.

[0254] The WTRU may measure interference from neighbor LAA cells. The WTRU may report interference for each neighbor LAA cell, or it may report aggregate interference measured on multiple (e.g., all) neighbor LAA cells. For example, the WTRU may measure interference on resources dedicated to neighbor LAA cells, and may report the sum of interference from multiple (e.g., all) neighbor LAA cells. In one example, the WTRU may be configured with resources available for it to measure neighbor LAA cell interference (e.g., configured by its serving cell (e.g., its PCell)). In another example, the WTRU may autonomously determine resources for measuring neighbor LAA cell interference. For example, the WTRU may determine interference measurement resources for neighbor cells based on signals transmitted from neighbor LAA cells. Elements available for the WTRU to autonomously determine neighbor cell interference measurement resources may include at least one of the following: neighbor cell ID; busy and / or synchronization and / or reference signal configuration; and preamble.

[0255] Parameters of one or more of the busy and / or synchronization and / or reference signal configuration may indicate resources to be used for interference measurement.

[0256] The LAASCell may transmit a preamble at the beginning of the active time, which may explicitly or implicitly indicate the interference measurement resources to the WTRU.

[0257] The WTRU may measure interference of neighbor cells on a configurable (or configured) signal. For example, the WTRU may measure interference of neighbor cells by measuring the results of a reference signal. The WTRU may measure the CQI of a neighbor cell and feed it back to its serving cell (e.g., PCell) as an interference measurement result. The WTRU may be configured with a precoder assumption in order to determine the CQI. In another example, the WTRU may simulate interference measurement results on neighbor cell signals. For example, the WTRU may be configured with a simulation formula and may obtain interference measurement results by measuring the results of neighbor cell signals and using the configured simulation formula.

[0258] When feeding back interference measurement results for one or more LAA channels and / or one or more neighbor LAA cells, the WTRU may report an enhanced measurement report. For example, the WTRU may be configured to have a set of interference measurement resources for which it can measure interference (which may be on a channel or from a neighboring cell). As an example, the set of interference measurement resources may include multiple measurement opportunities. The WTRU may be configured to have and / or may use functionality for determining interference and / or what information to report for the set of interference measurement resources.

[0259] Functionality available to the WTRU and / or reports transmitted by the WTRU to the eNodeB may include the average interference measurement result over the entire set of interference resources. Functionality available to the WTRU and / or reports transmitted by the WTRU to the eNodeB may include the maximum or minimum interference measured on any subset of the set of interference measurement resources. For example, the WTRU may report the interference measurement resource for which the maximum (or minimum) interference was measured and may report it together with the interference value. Functionality available to the WTRU and / or reports transmitted by the WTRU to the eNodeB may include the number of interference measurement resources that exceed or fall below a configurable threshold. For example, the WTRU may be configured to have a set of n interference measurement resources and may report the number of measurements k (where k≤n) that exceed the threshold. Doing so enables the eNodeB to determine the typical channel load over a period of time.

[0260] The WTRU may be configured to measure and / or report the SINR of a channel for a LAA cell. For example, the WTRU may be configured to have resources available for it to measure the signal strength in the LAA channel. The WTRU may be configured to have another set of resources available for it to measure interference plus noise on the LAA channel. The WTRU may reuse one or more of the methods described herein to measure the interference plus noise of the LAA channel. The SINR value may be quantized to limit the required feedback. In one example, the SINR may be quantized into two levels: unavailable channels and available channels. The availability of a channel may be defined as being available for the WTRU to receive data from the LAA cell with, for example, a certain or configurable (or configured) performance (e.g., BLER level).

[0261] The WTRU may be configured with one or more resources that it can use (or that it can attempt to use) to detect the presence of radar in the LAA channel. The measurement (eg, measurement result or conclusion) may be binary, such as whether radar is detected or not.

[0262] The WTRU may be configured with one or more resources (e.g., specific resources) on which it may report radar activity on an LAA channel, wherein the resource may be an UL resource (e.g., on a PCell). Reporting radar detection results (e.g., radar detected) using the resource may be considered to have high priority and take precedence over other (e.g., any other) transmissions from the WTRU that may conflict with the report (e.g., which may be scheduled or scheduled to be transmitted on the same UL resource, for example).

[0263] The radar detection feedback resource can be shared by one or more (e.g., all) WTRUs operating on the LAA channel. The radar detection indication will cause (e.g., any) WTRU that detects a radar on the LAA channel to transmit on the resource (e.g., in a joint manner). For example, each WTRU transmits the same signal. This ensures that the eNode B is aware of the presence of the radar. In one example, the WTRU may report (e.g., periodically or regularly) the radar monitoring status of the channel. In another example, the WTRU may trigger and / or transmit a radar monitoring report when or as a result of (e.g., only at this time or only as a result of) identifying the presence of a radar in the LAA channel.

[0264] In another example, the WTRU may use other (e.g., any other) reporting mechanisms defined herein to feedback measurement results similar to interference on the LAA channel. As an example, the WTRU may use or include an indication that is used to inform the network that the reported measurement result is a measurement result of a detected radar, rather than a result of no radar activity on the LAA channel. For example, the WTRU may be configured with interference measurement resources, and the WTRU may report interference measurement results in accordance with the embodiments or examples described herein. Once radar activity is detected on the interference measurement resources or as a result of the detection, the WTRU may trigger and / or transmit a report containing the interference measurement results to the eNode B. The WTRU may or may also report or include in the report an indicator (e.g., a flag) that may inform the network that the measured interference is from a radar and / or that a radar is detected. The report may include an identifier of the channel in which the radar is detected.

[0265] Measurements may be triggered by the results of other measurements. For example, a WTRU may be configured to have interference measurements on LAA channels. Once the interference measurement results meet the configured conditions (e.g., interference exists on the configured bandwidth) (or as a result thereof), the WTRU may be triggered to perform other measurement types, such as radar detection measurements. Doing so can reduce the battery consumption of the WTRU.

[0266] Figure 6 6 is a signal diagram of another exemplary method of a channel measurement and reporting mechanism for LTE operation in an unlicensed band. A WTRU 601 may receive an indication 603 from an eNodeB 602. The indication may indicate a time and / or frequency resource for performing measurements. The WTRU 602 may perform measurements 604 on the indicated time and / or frequency resource. The WTRU 602 may report the measurement results 605 to the eNodeB 602.

[0267] Although the features and elements are described above in specific combinations, it will be recognized by those skilled in the art that each feature or element can be used alone or in any combination with other features and elements. In addition, the methods described herein can be implemented in a computer program, software or firmware introduced into a computer-readable medium for operation by a computer or processor. Examples of computer-readable media include electrical signals (transmitted via a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, buffer memory, semiconductor storage devices, magnetic media (such as internal hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM discs and digital versatile discs (DVDs)). A processor associated with the software can be used to implement a radio frequency transceiver in a WTRU, a WTRU, a terminal, a base station, an RNC, or any computer host. Example 1. A method in a wireless communication system, the method comprising: Channel measurements for Long Term Evolution (LTE) operation in unlicensed bands are performed and channel measurement results are reported. 2. The method of embodiment 1, wherein the wireless transmit / receive unit (WTRU) measures the signal under the condition that the signal is not periodically available. 3. A method as described in any of the preceding embodiments, wherein the WTRU receives an indication from an evolved Node B (eNode B) to notify the WTRU to measure a signal. 4. A method as described in any of the preceding embodiments, wherein the indication is provided via physical layer signaling. 5. A method as described in any of the preceding embodiments, wherein the indication includes channel resources. 6. A method as described in any of the preceding embodiments, wherein the WTRU receives an indication from an eNodeB for notifying the WTRU to perform measurements at a time and frequency. 7. A method as described in any of the preceding embodiments, wherein the signal used for measurement is a measurement-related signal. 8. A method as described in any of the preceding embodiments, wherein the WTRU performs measurement in response to the measurement request. 9. A method as described in any of the preceding embodiments, wherein the WTRU reports the measurement result in a response to a measurement trigger. 10. A method as described in any of the preceding embodiments, wherein an LTE unlicensed (LTE-U) cell will wait to use an unlicensed frequency channel until the LTE-U cell detects that the channel is idle. 11. A method as described in any of the preceding embodiments, wherein the time during which the LTE-U cell uses a frequency channel is referred to as the activity time of the cell. 12. A method as described in any of the preceding embodiments, wherein the LTE-U cell performs transmission only during the active time. 13. A method as described in any of the preceding embodiments, wherein the LTE-U cell changes the resources used by the cell to transmit channels. 14. A method as described in any of the preceding embodiments, wherein the LTE-U cell changes resources that the cell will not use to transmit channels. 15. A method as described in any of the preceding embodiments, wherein channel resources are indicated in the time domain and the frequency domain. 16. A method as described in any of the preceding embodiments, wherein a resource element (RE) corresponds to a subcarrier in an orthogonal frequency division multiplexing (OFDM) symbol interval. 17. A method as described in any of the preceding embodiments, wherein a resource block (RB) indicates a set of channel resources in the time domain and the frequency domain. 18. A method as described in any of the preceding embodiments, wherein the RB represents multiple subcarriers. 19. A method as described in any of the preceding embodiments, wherein the RB corresponds to a time slot. 20. A method as described in any of the preceding embodiments, wherein the WTRU receives a measurement indication from an eNodeB. 21. A method as described in any of the preceding embodiments, wherein the measurement indication includes an indication of one or more channel resources containing measurement-related signals. 22. The method as recited in any preceding embodiment, wherein the measurement indication corresponds to one or more measurement-related signals. 23. A method as described in any of the preceding embodiments, wherein the WTRU determines the time and frequency resources where the signal exists. 24. A method as described in any of the preceding embodiments, wherein the WTRU performs measurements on channel resources in accordance with measurement instructions. 25. A method as described in any of the preceding embodiments, wherein the time period for the WTRU to perform measurements is a measurement period. 26. A method as described in any preceding embodiment, wherein the measurement indication includes an indication about the measurement period. 27. A method as described in any preceding embodiment, wherein the measurement indication includes a start time of the measurement period. 28. A method as described in any of the preceding embodiments, wherein the WTRU receives the measurement cycle start indication. 29. The method as in any preceding embodiment, wherein the measurement indication comprises the end of the measurement period. 30. A method as described in any of the preceding embodiments, wherein the WTRU receives the measurement period end indication. 31. A method as described in any preceding embodiment, wherein the measurement indication includes the length of the measurement period. 32. A method as described in any of the preceding embodiments, wherein once the measurement period starts, the WTRU starts measuring. 33. A method as described in any of the preceding embodiments, wherein the WTRU combines new measurement results with previous values ​​of the same type. 34. A method as described in any of the preceding embodiments, wherein the WTRU stops performing measurements after the measurement period ends. 35. A method as in any preceding embodiment, wherein the measurement indication comprises a pattern of time units of the measurement period. 36. A method as in any preceding embodiment, wherein the measurement-related signal is indicated by the measurement pattern. 37. A method as in any preceding embodiment, wherein an absence of one or more signals is indicated by the measurement pattern. 38. A method as in any preceding embodiment, wherein the measurement pattern identifies specific time units where a signal is absent. 39. A method as described in any of the preceding embodiments, wherein the measurement pattern is repeated within the measurement period. 40. The method as in any preceding embodiment, wherein the measurement pattern is the same in one or more frames within the measurement period. 41. A method as described in any of the preceding embodiments, wherein the measurement indication includes an indication of one or more cells and one or more frequency channels using the measurement indication. 42. A method as described in any of the preceding embodiments, wherein the WTRU receives measurement indications regarding one or more LTE-U cells. 43. The method as in any preceding embodiment, wherein the measurement indication activates one or more measurement processes. 44. A method as in any preceding embodiment, wherein the measurement indicates deactivation of one or more measurement processes. 45. A method as described in any of the preceding embodiments, wherein the measurement indication is provided in a downlink control information (DCI) signal. 46. ​​A method as described in any of the preceding embodiments, wherein the eNodeB transmits the measurement indication. 47. A method as described in any of the preceding embodiments, wherein the eNodeB transmits configuration information related to Licensed Assisted Access (LAA) measurements. 48. A method as described in any of the preceding embodiments, wherein the configuration information is provided in radio resource control (RRC) signaling. 49. A method as described in any of the preceding embodiments, wherein the measurement indication is cell-specific and has a radio network temporary identifier (RNTI) associated therewith and known to the WTRU. 50. The method as described in any preceding embodiment, wherein the measurement indication comprises a measurement request. 51. A method as described in any preceding embodiment, wherein the measurement indication requests a non-periodic measurement. 52. A method as described in any of the preceding embodiments, wherein the measurement request is for a current LAA cell. 53. A method as described in any of the preceding embodiments, wherein the measurement request is for different LAA cells. 54. A method as in any preceding embodiment, wherein the measurement represents a single measurement. 55. A method as in any preceding embodiment, wherein the measurement represents a specific measurement. 56. A method as described in any of the preceding embodiments, wherein the measurement represents a combination of one or more measurements. 57. A method as described in any of the preceding embodiments, wherein the measurement indication provides uplink resources. 58. A method as described in any of the preceding embodiments, wherein the eNodeB requests the WTRU to use the uplink (UL) resources to report the measurement results. 59. A method as described in any of the preceding embodiments, wherein the measurement helps the eNodeB select a channel to allocate to the WTRU. 60. A method as described in any of the preceding embodiments, wherein the WTRU indicates the measurement type in a measurement feedback report. 61. A method as described in any of the preceding embodiments, wherein the WTRU performs measurements in channel resources by searching for specific measurement-related signals. 62. A method as described in any of the preceding embodiments, wherein the WTRU is configured to have measurements on one or more LAA channels. 63. A method as described in any of the preceding embodiments, wherein the feedback is periodic. 64. A method as described in any of the preceding embodiments, wherein the feedback is on-demand. 65. A method as described in any of the preceding embodiments, wherein the WTRU is configured to have a reporting opportunity. 66. A method as described in any of the preceding embodiments, wherein the WTRU is configured to have an LAA channel measurement gap. 67. A method as described in any of the preceding embodiments, wherein the WTRU performs measurements on one or more LAA channels. 68. A method as described in any of the preceding embodiments, wherein the WTRU is granted UL resources. 69. A method as described in any of the preceding embodiments, wherein the eNode B indicates a measurement type and related measurement configuration in a request for measurement feedback. 70. A method as described in any of the preceding embodiments, wherein the WTRU performs averaging processing on measurement parameters in time and frequency. 71. A method as described in any of the preceding embodiments, wherein the WTRU reports measurement results when triggered. 72. A method as described in any of the preceding embodiments, wherein the timing for event-triggered measurement reporting is preconfigured. 73. The method as in any preceding embodiment, wherein a first measurement event triggering the first measurement report triggers a report on an associated second measurement. 74. A method as described in any of the preceding embodiments, wherein interference measurements on the LAA channel trigger processing for reporting the measurements. 75. A method as described in any of the preceding embodiments, wherein the WTRU is configured to have a set of resources for performing multiple measurements of the same type. 76. A method as described in any preceding embodiment, wherein one or more of the measurements triggers a measurement feedback report. 77. A method as described in any of the preceding embodiments, wherein the WTRU reports one or more interference measurement results to the eNodeB. 78. A method as described in any of the preceding embodiments, wherein the eNode B uses a measurement indication to request one or more WTRUs to measure one or more LAA frequency channels. 79. A method as described in any of the preceding embodiments, wherein the eNodeB uses the received report to select a frequency channel. 80. A method as described in any of the preceding embodiments, wherein the LAA unit allocates different resources to different channels. 81. A method as described in any of the preceding embodiments, wherein the LAA cell places one or more measurement-related signals in different channel resources. 82. A method as described in any of the preceding embodiments, wherein a channel state information (CSI) report is used for an LAA cell. 83. A method as described in any of the preceding embodiments, wherein the CSI report is non-periodic. 84. A method as described in any of the preceding embodiments, wherein the location of the measurement reference signal used for CSI measurement is at a specific time and frequency location of the LAA cell. 85. A method as described in any of the preceding embodiments, wherein the reference signal is a CSI-RS transmitted within a subframe. 86. A method as described in any of the preceding embodiments, wherein the eNode B requests the WTRU to report CSI associated with the LAA cell. 87. A method as described in any of the preceding embodiments, wherein a DCI with a specific RNTI is used to trigger a CSI report of an LAA cell. 88. A method as described in any of the preceding embodiments, wherein the measurement reference signal is transmitted based on the timing of one or more LAA resource bursts. 89. A method as described in any of the preceding embodiments, wherein the LAA resource burst is a time resource to be allocated to the LAA cell. 90. A method as described in any of the preceding embodiments, wherein the LAA resource burst is a time resource within a time window in an LAA cell. 91. A method as described in any of the preceding embodiments, wherein CSI measurement is timer triggered. 92. A method as described in any of the preceding embodiments, wherein the timer is set by the eNode B. 93. A method as described in any of the preceding embodiments, wherein if the timer expires, the WTRU measures the CSI in a subframe. 94. A method as described in any of the preceding embodiments, wherein a physical uplink control channel (PUCCH) in a primary cell (PCell) is used to report the LAA cell. 95. A method as described in any of the preceding embodiments, wherein the CSI reporting mode is based on PUCCH. 96. A method as described in any of the preceding embodiments, wherein one or more types of CSI reporting modes are used for LAA cells. 97. A method as described in any of the preceding embodiments, wherein the interference measurement report is non-periodic. 98. A method as described in any of the preceding embodiments, wherein interference measurement is performed using a measurement reference signal within the subframe. 99. A method as described in any of the preceding embodiments, wherein configuration information regarding an interference measurement reference signal (IM-RS) is provided to the WTRU. 100. A method as described in any of the preceding embodiments, wherein the DCI is used to trigger an interference level report and includes an IM-RS configuration. 101. A method as described in any of the preceding embodiments, wherein the WTRU reports the measured interference level in a specific subframe. 102. A method as described in any of the preceding embodiments, wherein separate transmission time interval (TTI) lengths are used for different cells. 103. A method as described in any of the preceding embodiments, wherein the reference resource uses a shortened TTI. 104. A method as described in any of the preceding embodiments, wherein the processing time of CSI measurement will be reduced. 105. A method as described in any of the preceding embodiments, wherein the WTRU is configured to report measurement results similar to a received signal strength indicator (RSSI). 106. A method as described in any of the preceding embodiments, wherein the WTRU is configured to perform interference measurements in one or more LAA cells. 107. A method as described in any of the preceding embodiments, wherein the WTRU is configured to measure and report the signal to interference and noise ratio (SINR) of the channel of the LAA cell. 108. A method as described in any of the preceding embodiments, wherein the WTRU is configured to have one or more resources for detecting the presence of a radar in a LAA channel. 109. A method as described in any of the preceding embodiments, wherein radar detection feedback resources are shared by one or more WTRUs operating in the LAA channel. 110. A method as described in any of the preceding embodiments, wherein if a radar is detected on the LAA channel, the radar detection indication instructs the WTRU to transmit on the resource. 111. A method as described in any of the preceding embodiments, wherein the WTRU communicates with a primary cell operating in a licensed frequency band. 112. A method as described in any of the preceding embodiments, wherein the WTRU communicates with a secondary cell operating in an unlicensed frequency band. 113. The method as described in any of the preceding embodiments, further comprising: The WTRU receives a request in a DCI for measurements and reporting. 114. A method as described in any of the preceding embodiments, wherein the request for measurement and reporting indicates at least one time / frequency resource in at least one subframe for performing measurements in an unlicensed frequency band. 115. The method as described in any of the preceding embodiments, further comprising: The WTRU performs measurements in accordance with the request for measurements and reporting. 116. The method as described in any of the preceding embodiments, further comprising: The WTRU sends a measurement report based on the measurements performed. 117. A method as described in any of the preceding embodiments, wherein the at least one time / frequency resource indicated is a set of physical resource blocks (PRBs) or resource elements (REs). 118. A method as described in any of the preceding embodiments, wherein the indicated at least one time / frequency resource corresponds to a RE set, and the RE set may include REs for one or more of a channel state information reference signal (CSI-RS), a CSI interference measurement (IM), a zero-power CSI-RS, or a cell-specific reference signal (CRS). 119. A method as described in any of the preceding embodiments, wherein the at least one subframe used to perform the measurement is the requested subframe or a subframe window starting with the requested subframe. 120. A method as described in any of the preceding embodiments, wherein the measurement report includes an identifier of a subframe or system frame number (SFN) associated with the measurement. 121. A method as described in any of the preceding embodiments, wherein the WTRU is semi-statically configured to have a set of multiple LAA channels and / or LAA cells for measurement. 122. The method as described in any of the preceding embodiments, further comprising: The WTRU performs measurements on one or more LAA channels during times configured as measurement gaps. 123. A method as described in any of the preceding embodiments, wherein the request is an information element, or a bit string, or both. 124. A method as described in any of the preceding embodiments, wherein the measurement indication includes an index for indicating a set of LAA channels for the WTRU to perform measurements. 125. A method as described in any of the preceding embodiments, wherein the DCI includes feedback resources for use by the WTRU in measurement reporting. 126. A method as described in any of the preceding embodiments, wherein the WTRU is configured to have a reporting threshold for WTRU event-driven reporting processing. 127. A method as described in any of the preceding embodiments, wherein the WTRU is configured with a table that maps measurement ranges to reporting code points. 128. A method as described in any of the preceding embodiments, wherein the measurement report is sent when the LAA cell is in an active state or the LAA cell is in an active time. 129. A method as described in any of the preceding embodiments, wherein the interference report is sent under one or more of the following conditions: the applicable IM-RS is valid, the timer expires, the report trigger has been achieved, or valid reporting resources are available. 130. A method as described in any of the preceding embodiments, wherein the reporting resources are determined to be valid if one or more of the following situations occur: the WTRU has successfully obtained an unauthorized channel on which the measurement report is to be transmitted, the WTRU is configured as a resource on another cell, and the reporting resources are not pre-occupied for other reasons. 131. A WTRU configured to perform a method as described in any of the preceding embodiments, comprising: Receiver; transmitter; and A processor that communicates with the transmitter and receiver. 132. A base station configured to perform the method as described in any one of embodiments 1-130. 133. An integrated circuit configured to perform the method as described in any one of embodiments 1-130. 134. A method for implementing a channel measurement and reporting mechanism in a wireless transmit / receive unit (WTRU) for long term evolution (LTE) operation in an unlicensed band, the method comprising: receiving an indication from an evolved Node B (eNode B) indicating time and frequency resources for performing measurements; performing measurements on the indicated time and frequency resources; and Report the measurement results to the eNodeB. 135. A method performed in a wireless transmit / receive unit (WTRU) communicating with a primary cell operating in a licensed frequency band and a secondary cell operating in an unlicensed frequency band, the method comprising: The WTRU receives a request for measurement and reporting in a downlink control information (DCI) signal, wherein the request indicates at least one time / frequency resource in at least one subframe for performing measurements in an unlicensed frequency band; The WTRU performs measurements according to the request; and The WTRU transmits a measurement report based on the performed measurements. 136. A method as described in embodiment 135, wherein the at least one time / frequency resource indicated is a set of physical resource blocks (PRBs) or resource elements (REs). 137. A method as described in embodiment 135, wherein the indicated at least one time / frequency resource corresponds to a RE set, and the RE set may include REs for one or more of a channel state information reference signal (CSI-RS), a CSI-interference measurement (IM), a zero-power CSI-RS, or a cell-specific reference signal (CRS). 138. The method of embodiment 135, wherein the at least one subframe used to perform the measurement is the requested subframe or a subframe window starting from the requested subframe. 139. A method as described in embodiment 135, wherein the measurement report includes an identifier of a subframe or system frame number (SFN) associated with the measurement.

Claims

1. A wireless transmit / receive unit (WTRU), the WTRU comprising: A processor configured to: receiving configuration information associated with activation or deactivation of one or more measurements; Based on the configuration information, receiving a first signal; Based on the first signal and the configuration information, measurements are performed.

2. The WTRU of claim 1 , wherein the processor being configured to receive the configuration information comprises: The processor receives an indication for activating or deactivating a measurement or a measurement cycle, and wherein the processor is further configured to activate the measurement or the measurement cycle to perform the measurement.

3. The WTRU of claim 2, wherein the processor is further configured to receive a second signal, wherein the second signal comprises an indication to deactivate the measurement or the measurement cycle.

4. The WTRU of claim 3, wherein the processor is further configured to deactivate the measurement or the measurement cycle based on the second signal.

5. The WTRU of claim 1 , wherein the processor is further configured to transmit a measurement report based on the first signal.

6. A wireless transmit / receive unit (WTRU), the WTRU comprising: A processor configured to: receiving configuration information via first downlink control information (DCI), wherein the configuration information includes first measurement indication information indicating activation of measurement reporting and an indication for a first plurality of resource element (RE) sets, wherein the first DCI includes at least a channel state information radio network temporary identifier (CSI-RNTI) associated with the first DCI, and wherein each of the plurality of RE sets is associated with measurement-related time and frequency resources; Determining, based at least on the CSI-RNTI, that the first DCI includes the indication; Determine a first RE set based on the first measurement indication information; activating a measurement period based on the indication for activating the measurement report; receiving one or more measurement-related signals in at least one of the first plurality of sets of REs; During the measurement period, performing a measurement of each measurement-related signal; During the measurement period, sending a measurement report based on the measurement report of each measurement-related signal and based on the measurement indication information; receiving a second DCI, wherein the second DCI includes a second CSI-RNTI, wherein the second DCI includes second measurement indication information indicating deactivation of the measurement report; Determine, based on the second CSI-RNTI, that the second DCI includes the second measurement indication information to deactivate the measurement period; The measurement period is deactivated based on the second measurement indication information.

7. The WTRU of claim 6, wherein the processor further comprises: An indication of a second plurality of RE sets is received via radio resource control (RRC) signaling.

8. The WTRU of claim 7, wherein the first RE set is determined from the plurality of RE sets based on an index in the first measurement indication information.

9. The WTRU of claim 6, wherein the first measurement indication information comprises an identification of uplink (UL) resources used for the transmission of the measurement report.

10. The WTRU of claim 6, wherein the one or more measurement-related signals include one or more CSI reference signals (CSI-RS).

11. A wireless transmit / receive unit (WTRU), the WTRU comprising: A processor configured to: receiving configuration information indicative of one or more signals; receiving an indication to report one or more measurements; as well as Based on the indication, one or more measurement reports are sent.

12. The WTRU of claim 11, wherein the processor is further configured to receive a second indication, wherein the second indication is used to indicate that a set of one or more measurement-related signals associated with a set of resource elements (REs) has been activated.

13. The WTRU of claim 12, wherein the one or more measurement reports are sent based on the second indication.

14. The WTRU of claim 12, wherein the processor is configured to receive a third indication indicating deactivation of the one or more measurement-related signals.

15. The WTRU of claim 12, wherein the processor is configured to receive the configuration information via a radio resource control (RRC) message, wherein the processor is configured to send the one or more measurements based on receipt of the indication.

16. The WTRU of claim 12, wherein the set of one or more measurement-related signals comprises a first set of one or more channel state information interference measurement (CSI-IM) signals.

17. The WTRU of claim 12, wherein the set of one or more measurement-related signals comprises a first set of one or more non-zero power channel state information reference signals (CSI-RS).

18. The WTRU of claim 12, wherein the second indication is used to indicate uplink resources used to send the one or more measurement reports, wherein the uplink resources correspond to one or more physical uplink channels or physical uplink channel resources.

19. The WTRU of claim 11, wherein the indication is used to indicate a measurement type to be reported, wherein the measurement type corresponds to a reference signal received power (RSRP) measurement.

20. A wireless transmit / receive unit (WTRU), the WTRU comprising: A processor configured to: receiving configuration information indicating one or more LAA channels or one or more LAA cells from a network node; Receiving one or more signals via the one or more LAA channels or the one or more LAA cells, wherein the one or more signals are included in an LAA resource burst; determining a first set of interfering signals based on the received one or more signals; and The first set of interference signals is reported based on one or more conditions being met, wherein the one or more conditions at least include a timer-based determination.

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