Reducing latency of physical channels in LTE networks

Abstract

The invention relates to reducing latency of physical channels in LTE networks. A wireless transmit receive unit (WTRU) may monitor a downlink short transmission time interval (sTTI) physical downlink control channel (sPDCCH) region over the sTTI. The WTRU may determine an sPDCCH region for the uplink grant from a set of candidate sPDCCH regions. The sPDCCH may be determined based on a parameter specific to the WTRU.

Description

This application is a divisional application of Chinese Patent Application No. 201780020914.6, filed March 30, 2017, entitled "Reducing Latency of Physical Channels in LTE Networks," the contents of which are incorporated herein in its entirety by this reference. Cross Reference to Related Applications

[0001] This application claims the benefit of U.S. Provisional Application No. 62 / 315,490, filed March 30, 2016, U.S. Provisional Application No. 62 / 334,888, filed May 11, 2016, and U.S. Provisional Application No. 62 / 377,181, filed August 19, 2016, the contents of which are incorporated herein in their entirety by this reference. BACKGROUND

[0002] In Long Term Evolution (LTE) or LTE-Advanced (LTE-A) networks, it would be desirable to reduce the latency for applications such as shortened alarm systems, automotive safety, factory systems, or machine type communications (MTC). In addition, gaming and real-time applications such as Voice over LTE (VoLTE), video telephony, or video conferencing over LTE would also benefit from reduced latency. Scheduling grant acquisition time, transmission time interval (TTI), processing time, or hybrid-ARQ (HARQ) round trip time (RTT) can also contribute to end-to-end delay. Thus, it would be desirable to reduce latency in wireless networks by addressing these and other factors that can contribute to delay. SUMMARY

[0003] A wireless transmit / receive unit (WTRU) can transmit transmissions that are mostly or partially overlapping in time to the network or an evolved Node-B. By using scaling, it is possible to avoid exceeding maximum power or energy levels in a transmission time interval (TTI) or a portion of a TTI. The WTRU can be further configured to determine short TTI (sTTI) time resources in a period of time including a subframe, a radio frame, a time slot, or a symbol, among other possibilities, for use in control or data transmissions, which can reduce latency. In addition, power headroom (PH) reporting can use TTIs or sTTIs. BRIEF DESCRIPTION OF DRAWINGS

[0004] A more detailed understanding can be had from the following description, given by way of example in conjunction with the accompanying drawings wherein:

[0005] FIG. 1A is a system diagram of an example communications system in which one or more disclosed embodiments can be implemented;

[0006] FIG. 1B is a system diagram of an example communications system in which one or more disclosed embodiments can be implemented; FIG. 1ASystem diagram of example wireless transmit / receive units (WTRUs) used internally in the illustrated communication system;

[0007] FIG. 1C is an example of a physical resource block (PRB) mapping for one or more physical uplink control channel (PUCCH) transmissions or one or more PUCCH format transmissions; FIG. 1A System diagram of example radio access network and example core network used internally in the illustrated communication system;

[0008] FIG. 2 is an example of a physical resource block (PRB) mapping for one or more physical uplink control channel (PUCCH) transmissions or one or more PUCCH format transmissions;

[0009] FIG. 3 is an example of a physical uplink shared channel (PUSCH) resource mapping;

[0010] FIG. 4 is an example of a time division duplex (TDD) specific subframe configuration;

[0011] FIG. 5 is an example of a short transmission time interval (sTTI) gap indication;

[0012] FIG. 6 is an example of a multi-gap sTTI indication;

[0013] FIG. 7 is an example of a sTTI resource configuration in a subframe guard period (GP);

[0014] FIG. 8 is an example of a short or sTTI PUCCH (sPUCCH) resource configuration provided in a downlink subframe or PRB;

[0015] FIG. 9 is an example of a 2-symbol short or sTTI PUCCH (sPUCCH);

[0016] FIG. 10 is an example of a 3-symbol sPUCCH;

[0017] FIG. 11 is an example of a 4-symbol sPUCCH;

[0018] FIG. 12 is an example of a 1-symbol sPUCCH signal structure;

[0019] FIG. 13 is an example of a multi-symbol sPUCCH signal structure without UL reference signals;

[0020] FIG. 14 is an example of a 1-symbol sPUCCH signal structure repeated over several resource blocks (RBs);

[0021] FIG. 15 is an example of short or sTTI PUCCH (sPUCCH) scheduling with one or more associated short or sTTI physical downlink control channel (sPDCCH) regions;

[0022] FIG. 16 is an example of association between sPUSCH and at least one sPDCCH for HARQ-ACK feedback reception when UL and DL sTTI lengths are different;

[0023] FIG. 17 is an example of association between sPUCCH for HARQ-ACK transmission and at least one short or sTTI physical downlink shared data channel (sPDSCH) when UL and DL sTTI lengths are different;

[0024] FIG. 18 is an example of collision between PUCCH and sPUCCH;

[0025] FIG. 19 is an example of normal HARQ (nHARQ) transmission on sPUCCH;

[0026] FIG. 20 is an example of overlapping or concurrent TTIs;

[0027] FIG. 21 is an example of power headroom (PH) reporting; and

[0028] FIG. 22 is an example of sPDCCH region determination. DETAILED DESCRIPTION

[0029] Any element shown or described in the figures hereof can be implemented by one or more functional or component elements of hardware, software, firmware, or the like. Further, in the examples hereof, a transmitter can be a transceiver or part of a multi-component hardware element as needed. A receiver can be a transceiver or part of a multi-component hardware element as needed. Finally, the term data or information in any example hereof can include control data, control information, one or more control packets, user data, user information, payload data, payload information, one or more data packets, general data, or general information as needed.

[0030] FIG. 1AFIG2 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 such content by sharing system resources, including wireless bandwidth. For example, the communication system 100 may utilize 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), among others.

[0031] like FIG. 1A As shown, the communication system 100 may include a wireless transmit / receive unit (WTRU) 102a, 102b, 102c, or 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. However, it should be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, or network components. Each WTRU 102a, 102b, 102c, or 102d may be any type of device configured to operate and / or communicate in a wireless environment. For example, the WTRU 102a, 102b, 102c, or 102d may be configured to transmit and / or receive wireless signals and may include a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, a cellular phone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, or a consumer electronic device, among others. A signal may be or include a channel, a physical channel, a control channel, a data channel, or a physical channel that can be used as a control channel or a data channel, etc. A signal may be or include a reference signal (RS). Signal and channel may be used interchangeably.

[0032] 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 wirelessly interface with at least one WTRU 102a, 102b, 102c, or 102d to facilitate access to one or more communication networks, such as the core network 106, the Internet 110, and / or other networks 112. By way of example, the base station 114a or 114b may be 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 or 114b is depicted as a single component, it should be appreciated that the base station 114a or 114b may include any number of interconnected base stations or network components.

[0033] The base stations 114a can be part of a RAN 104, which can also include other base stations or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), or relay nodes, among others. The base stations 114a or the base stations 114b can be configured to transmit or receive wireless signals within a particular geographic area, which can be referred to as a cell (not shown). The cell can further be divided into cell sectors. For example, the cell associated with a base station 114a can be divided into three sectors. Thus, in one embodiment, the base station 114a can include three transceivers, one for each of the three sectors of the cell. In another embodiment, the base station 114a can utilize a multiple-input multiple-output (MIMO) technique and, thus, can utilize multiple transceivers for each sector of the cell.

[0034] The base stations 114a or 114b can communicate with one or more WTRUs 102a, 102b, 102c, or 102d over an air interface 116, which can be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 can be established using any suitable radio access technology (RAT).

[0035] More specifically, as noted above, the communications system 100 can be a multiple access system and can employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station 114a in the RAN 104 and the WTRUs 102a, 102b, or 102c can implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which can establish the air interface 116 using wideband CDMA (WCDMA). WCDMA can include communication protocols such as High-Speed Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA can include High-Speed Downlink Packet Access (HSDPA) or High-Speed Uplink Packet Access (HSUPA).

[0036] In another embodiment, the base station 114a and the WTRUs 102a, 102b, or 102c can implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which can establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A). In the future, the base station 114a and the WTRUs 102a, 102b, or 102c can implement a radio technology such as Fifth Generation (5G) New Radio (NR). In such an embodiment, the base station 114a and the WTRUs 102a, 102b, or 102c can implement a radio technology such as NR, which can establish the air interface 116 using OFDMA or CDMA. In an embodiment, the WTRU 102a can utilize sidelink communication techniques to communicate with the WTRU 102b or 102c.

[0037] In other embodiments, the base station 114a and WTRUs 102a, 102b, or 102c can implement radio technologies such as IEEE 802.16 (worldwide interoperability for microwave access (WiMAX)), CDMA2000, CDMA2000 IX, 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), or GSM EDGE (GERAN), among other wireless communication protocols.

[0038] By way of example, FIG. 1A The base station 114b in FIG. 1C can be a wireless router, Home Node B, Home eNode B, or access point, for example, and can utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d can implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In another embodiment, the base station 114b and the WTRUs 102c, 102d can implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d can utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.) to establish a picocell or femtocell. As shown, the base station 114b can have a direct connection to the Internet 110. Thus, the base station 114b can not be required to access the Internet 110 via the core network 106. FIG. 1A The RAN 104 can be in communication with the core network 106, which can be any type of network configured to provide voice, data, applications, or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, or 102d. For example, the core network 106 can provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., or perform high-level security functions such as user authentication.

[0039] The RAN 104 can be in communication with the core network 106, which can be any type of network configured to provide voice, data, applications, or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, or 102d. For example, the core network 106 can provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., or perform high-level security functions such as user authentication. FIG. 1AIt is to be understood that the RAN 104 or the core network 106 can each include any combination of elements, as is appreciated by those skilled in the art, given the teachings contained herein. Also, the RAN 104 and / or the core network 106 can be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104, which can be utilizing a cellular-based RAT, the core network 106 can also be in communication with another RAN (not shown) that can be utilizing a GSM-based RAT.

[0040] The core network 106 can also serve as a gateway for the WTRUs 102a, 102b, 102c, or 102d to access the PSTN 108, the Internet 110, or other networks 112. The PSTN 108 can include circuit-switched telephone networks that provide infrastructure for the provision of voice telephony. The Internet 110 can include a global system of interconnected computer networks and devices that use the common internet protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP) and the internet Protocol (IP) in the TCP / IP family of protocols. The networks 112 can include wired or wireless communications networks owned and / or operated by other service providers. For example, the networks 112 can include another core network connected to one or more RANs, which can employ the same RAT as the RAN 104 or a different RAT.

[0041] Some or all of the WTRUs 102a, 102b, 102c, or 102d in the communications system 100 can include multi-mode capabilities, i.e., the WTRUs 102a, 102b, 102c, or 102d can include multiple transceivers for communicating with different wireless networks over different wireless links. For example, the WTRU 102a, 102b, 102c, or 102d can include a transceiver 150a, and a FIG. 1A The WTRU 102c shown in Figure 1 A can be configured to communicate with the base station 114a using a cellular-based radio technology and can also be configured to communicate with the base station 114b using an IEEE 802 radio technology.

[0042] FIG. 1B is a system diagram of an example WTRU 102. As shown in FIG. 1B The WTRU 102 can include a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and other peripherals 138, among others. It will be appreciated that the WTRU 102 can include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0043] The processor 118 can 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 in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Array (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 can perform signal coding, data processing, power control, input / output processing, or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 can be coupled to the transceiver 120, which can be coupled to the transmit / receive element 122. While FIG. 1B The processor 118 and the transceiver 120 are depicted as separate components, it is to be understood that the processor 118 and the transceiver 120 can be integrated together in an electronic package or chip.

[0044] The transmit / receive element 122 can be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, the transmit / receive element 122 can be an antenna configured to transmit or receive RF signals. In another embodiment, the transmit / receive element 122 can be an emitter / detector configured to transmit or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit / receive element 122 can be configured to transmit and receive both RF and light signals. It will be appreciated that the transmit / receive element 122 can be configured to transmit or receive any combination of wireless signals.

[0045] In addition, although the transmit / receive element 122 is depicted in the FIG. 1B WTRU 102 can include any number of transmit / receive elements 122. More specifically, the WTRU 102 can employ MIMO technology. Thus, in one embodiment, the WTRU 102 can include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0046] The transceiver 120 can be configured to modulate the signals that are to be transmitted by the transmit / receive element 122 and to demodulate the signals that are received by the transmit / receive element 122. As noted above, the WTRU 102 can have multi-mode capabilities. Thus, the transceiver 120 can include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as UTRA and IEEE 802.11, for example.

[0047] The processor 118 of the WTRU 102 can be coupled to, and can receive user input data from, the speaker / microphone 124, the keypad 126, or the display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit). The processor 118 can also output user data to the speaker / microphone 124, the keypad 126, or the display / touchpad 128. In addition, the processor 118 can access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 or the removable memory 132. The non-removable memory 130 can include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 can 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 can access information from, or store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0048] The processor 118 can receive power from the power source 134, and can be configured to distribute or control the power to the other components in the WTRU 102. The power source 134 can be any suitable device for powering the WTRU 102. For example, the power source 134 can include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, or the like.

[0049] The processor 118 can also be coupled to the GPS chipset 136, which can be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 can receive location information over the air interface 116 from a base station (e.g., base stations 114a, 114b) or determine its location based on

[0050] The processor 118 can further couple to other peripherals 138, which can include one or more software or hardware modules that provide additional features, functionality or interfaces to the WTRU 102. For example, the peripherals 138 can include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands- free headset, a Bluetooth® module, a frequency modulated (FM) radio a module, a Frequency Modulation (FM) radio unit, a digital music player, a media player, a video game console module, or an Internet browser, etc.

[0051] FIG. 1C A system -level diagram of a RAN 104 and a core network 106 according to an embodiment is shown. As described above, the RAN 104 can be in communication with the WTRUs 102a, 102b, 102c in the UTRA network 104 and can utilize E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 can also be in communication with the core network 106.

[0052] The RAN 104 can include eNode-Bs 140a, 140b, or 140c, though it will be appreciated that the RAN 104 can include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 140a, 140b, or 140c can each 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, or 140c can implement MIMO technology. Thus, the eNode-B 140a, for example, can use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a.

[0053] Each of the eNode-Bs 140a, 140b, or 140c can be associated with a particular cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, or scheduling of users or downlink or uplink transmissions in the associated cell, etc. As shown, the eNode-Bs 140a, 140b, or 140c can communicate with one another over an X2 interface. FIG. 1C The core network 106 shown includes a mobility management gateway (MME) 142, a serving gateway 144, and a packet data network (PDN) gateway 146. While each of the foregoing elements are depicted as part of the core network 106, it will be appreciated that any one of these elements can be owned and / or operated by an entity other than the core network operator.

[0054] FIG. 1C The core network 106 shown includes a mobility management gateway (MME) 142, a serving gateway 144, and a packet data network (PDN) gateway 146. While each of the foregoing elements are depicted as part of the core network 106, it will be appreciated that any one of these elements can be owned and / or operated by an entity other than the core network operator.

[0055] The MME 142 may be connected to each eNode-B 140a, 140b, or 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 WTRU 102a, 102b, or 102c, performing bearer activation / deactivation, or selecting a particular serving gateway during an initial attach of the WTRU 102a, 102b, or 102c. 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.

[0056] The serving gateway 144 may be connected to each eNode-B 140a, 140b, or 140c in the RAN 104 via an S1 interface. The serving gateway 144 may generally route and forward user data packets to and from the WTRU 102a, 102b, or 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 WTRU 102a, 102b, or 102c, or managing and storing the context of the WTRU 102a, 102b, or 102c.

[0057] The serving gateway 144 may also be connected to a PDN gateway 146, which may provide the WTRU 102a, 102b, or 102c with access to packet-switched networks, such as the Internet, to facilitate communications between the WTRU 102a, 102b, or 102c and IP-enabled devices.

[0058] The core network 106 may facilitate communications with other networks. For example, the core network 106 may provide the WTRU 102a, 102b, or 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRU 102a, 102b, or 102c and traditional land-line communications devices. For example, the core network 106 may include or communicate 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 WTRU 102a, 102b, or 102c with access to other networks 112, which may include other wired or wireless networks owned or operated by other service providers.

[0059] Other networks 112 can also further connect to an IEEE 802.11 based wireless local area network (WLAN) 160. The WLAN 160 can include an access router 165. The access router 165 can contain gateway functionality. Also, the access router 165 can be in communication with a plurality of access points (APs) 170a or 170b. Communication between the access router 165 and the APs 170a or 170b can be over a wired Ethernet (IEEE 802.3 standard) or any type of wireless communication protocol. The AP 170a wirelessly communicates with the WTRU 102d over an air interface.

[0060] In examples presented herein, a WTRU 102 can be configured to determine short TTI (sTTI) time resources in a time period. The sTTI can be a subframe, a radio frame, a slot, a timeslot, a symbol, a plurality of symbols, an OFDM symbol, or a plurality of OFDM symbols, among other examples. In the present disclosure, the term time or time period can be replaced with symbol. The WTRU can transmit a single physical uplink control channel (PUCCH) containing a plurality of short or sTTI hybrid automatic repeat request (sHARQ) transmissions and one or more regular HARQ transmissions. In addition, the WTRU can scale transmissions performed by the WTRU to avoid exceeding a maximum power level. The scaling can include scaling power of a channel, frequency, slot, or symbol, among other examples. The WTRU can also perform or can be configured to perform a power headroom (PH) reporting (PHR) procedure using nTTI, sTTI, or a combination of both. The nTTI can be a nominal, normal, or regular TTI or subframe, such as a LTE / LTE-A TTI or subframe. The nTTI can be a TTI that is longer than the sTTI. The nTTI can be any value, such as 1 millisecond or any other duration. The WTRU can receive an indication to perform a PHR procedure, where the indication contains a resource grant for one or more uplink transmissions. In response to receiving the indication, the WTRU can transmit a PH report based on the indicated resource grant. The resource grant can indicate the nTTI, sTTI, or a combination of both to be used. The nTTI can be of a first serving cell and the short or sTTI can be of a second serving cell. The first serving cell and the second serving cell can be the same or different serving cells. The WTRU can or can be configured to aggregate the first serving cell and the second serving cell.

[0061] Also, in the examples given herein, a PUCCH can be used for one or more HARQ-ACK transmissions or reports, which can be associated with one or more physical downlink shared data channel (PDSCH) transmissions, one or more scheduling request (SR) transmissions, or one or more channel state information (CSI) transmissions. As an example, one or more PUCCH formats can be defined, determined, or used based on information carried in a PDCCH. For example, a PUCCH format that can carry HARQ-ACK information (e.g., only HARQ-ACK information) can be referred to as PUCCH format la or PUCCH format lb.

[0062] FIG. 2 is an example of a physical resource block (PRB) mapping 200 for one or more PUCCH transmissions or one or more PUCCH format transmissions. A PUCCH can be allocated in connection with a physical downlink control channel (PDCCH). Physical resources that can be used for a PUCCH can be determined based on one or more parameters, such as and parameters may be or can represent a frequency resource, such as a frequency bandwidth, where may be greater than or equal to 0. A PRB or resource block (RB) can be or can include a set of subcarriers, such as 12 subcarriers, in or associated with a system bandwidth. Scheduling or resource allocation can be made in terms of RBs. An RB can represent or correspond to a set of one or more time units. For example, an RB can correspond to a TTI length or a portion of a TTI length. Frequency resources can be defined, allocated, or represented in terms of PRBs, where the PRBs can be configured, determined, or used for PUCCH formats or PUCCH format transmissions. Examples of PUCCH formats include 1 / la / lb, 2 / 2a / 2b, and 3. In embodiments and examples herein, PRB and RB are interchangeable.

[0063] A PUCCH transmission or a PUCCH format transmission can be in one or more slots or time slots. There can be two slots in a subframe. A PUCCH or a PUCCH format transmission can be made in each slot of a subframe. As an example, a parameter may be used to determine a number of cyclic shifts available for use by a PUCCH format, such as PUCCH format 1 / la / lb, in a physical resource block that can be used for or configured for PUCCH format mixing. As an example, PUCCH format mixing can be a mixing of formats 1 / la / lb and 2 / 2a / 2b. may have a value in a range of {0, 1,..., 7} Integer multiples of It can be provided by higher layers or signaled. For example, when For resource blocks (e.g., one resource block or at most one resource block) in a time slot (e.g., in each time slot), a mix of PUCCH formats such as PUCCH formats 1 / 1a / 1b and 2 / 2a / 2b may be supported.

[0064] The resources available for transmitting PUCCH formats 1 / 1a / 1b, 2 / 2a / 2b and 3 can be indexed by non-negative indices and It can be represented by time slot n s PUCCH transmission or PUCCH format transmission configuration or physical resource block n used PRB It can be determined by the parameter m, for example, according to the following equation: The value of m can be determined based on the PUCCH format. For example, for PUCCH formats (such as PUCCH formats 1, 1a, and 1b), the following equation can be used to determine m:

[0065] For PUCCH formats (e.g., PUCCH formats 2, 2a, and 2b), the following equation may be used to determine m: For a PUCCH format (e.g., PUCCH format 3), the following equation may be used to determine m:

[0066] exist FIG. 2 In the example of FIG, the PRB mapping for PUCCH transmission is shown to be based on the parameter m within the subframe.

[0067] A shortened PUCCH format may be provided or used. When using a shortened PUCCH format, the last SC-FDMA symbol in the second slot of a subframe may be left empty. As an example, a shortened PUCCH format may be used when simultaneously transmitting a sounding reference signal (SRS) and a PUCCH transmission or a PUCCH format transmission. This configuration may be used for transmissions of PUCCH formats 1, 1a, 1b, or 3, or may be used with one serving cell.

[0068] FIG. 3is an example of a physical uplink shared channel (PUSCH) resource mapping 300 within a PRB and an uplink subframe 302. The PUSCH can be used for one or more transmissions of data 314. A demodulation reference signal (DM-RS) 316 for the PUSCH can be signaled, for example, in the middle of the first slot 304 or the second slot 306, or in the middle of each slot 308 or the 4th symbol 308. An acknowledgement (ACK) or negative acknowledgement (NACK) 318 can be communicated on one or more symbols 310. A last symbol 312 of the uplink subframe 302 (e.g., a subframe for which PUSCH can be allocated, scheduled, or used) can be used for a sounding reference signal (SRS) 320. A symbol (e.g., a last symbol in a subframe) can be used for SRS transmission by the same WTRU that transmits PUSCH in the subframe or by a different WTRU. If an uplink subframe is potentially used for SRS transmission, and a PRB allocated for PUSCH transmission can be used for SRS transmission, the WTRU does not transmit PUSCH in the last symbol. The first slot 304 can be designated as slot 0 and the second slot 306 can be designated as slot 1. As an example, if PUSCH frequency hopping is configured or activated, different frequency locations or PRB locations can be used for PUSCH transmission in the first slot 304 and the second slot 306.

[0069] In addition, one or more subframes can be configured, at least in part, for uplink and can be configured, at least in part, for downlink. A particular subframe can be or can be used to represent a subframe that is configured, at least in part, for uplink and configured, at least in part, for downlink. A particular subframe can be or can be used to represent a subframe that is configured, at least at times, for uplink and configured, at least at times, for downlink. As an example, a particular subframe is a subframe that can be configured or used within a frame or radio frame. One or more particular subframes can apply to time division duplex (TDD) operation or operation that time shares a frequency or a frequency band between uplink and downlink transmissions. A number of particular subframes in a radio frame or one or more time locations of one or more particular subframes in a radio frame can be determined based on a UL-DL subframe configuration, such as a TDD UL-DL subframe configuration. Table 1

[0070] Table 1 shows example TDD UL-DL subframe configurations within a radio frame, where D can represent a downlink subframe that can contain downlink symbols, U can represent an uplink subframe that can contain uplink symbols, and S can represent a special subframe. A special subframe can include at least one of a downlink symbol, an uplink symbol, and a guard time or symbol. For example, a special subframe can include at least one downlink symbol, at least one uplink symbol, and at least one symbol (or other time) as a guard period between the downlink symbols and the uplink symbols. In a special subframe, one or more downlink symbols can be referred to as a downlink pilot time slot (DwPTS) and one or more uplink symbols can be referred to as an uplink pilot time slot (UpPTS). In addition, one or more symbols (or time) that are not used for DwPTS or UpPTS can be referred to as a gap period or guard period (GP).

[0071] The GP in a special subframe can be located between the DwPTS and the UpPTS. The number of symbols or time that can be used for the DwPTS, UpPTS, and GP of a special subframe can be determined based on the special subframe configuration, and Table 2 shows examples regarding special subframe configurations and the number of symbols that can be used for the DwPTS, UpPTS, and GP. Table 2

[0072] FIG. 4 is an example of a configuration of a special subframe 408 with DwPTS symbols 414, GP symbols 416, and UpPTS symbols 418. The special subframe configuration 0-8 can be configured or used in the special subframe 408, for example, as the special subframe configuration 0-8 from Table 2. As an example, three downlink symbols 404 can be used for the DwPTS, one uplink symbol 412 can be used for the UpPTS 406, and the remaining symbols 410 in the subframe can be used as a GP in special subframe configuration #0.

[0073] A WTRU can assume that there are no downlink signals in the GP symbols 416. In symbols that can be used or intended for the GP, the WTRU can not attempt to decode signals or transmissions, receive signals or transmissions, measure signals or transmissions, estimate signals or transmissions, or transmit signals or other transmissions, among other examples.

[0074] One or more downlink (DL) signals, channels, data channels, or control channels can be transmitted or received in the DL symbol or DwPTS symbol 414. The one or more DL signals or channels can include one or more reference signals, a cell-specific reference signal (CRS), or a DL DM-RS, among others. One or more uplink (UL) signals, channels, data channels, or control channels can be transmitted or received in the UL symbol or UpPTS symbol 418. The one or more UL signals or channels can include one or more reference signals, such as an UL DM-RS or SRS. A pilot signal can also be a reference signal.

[0075] For a subframe that can be configured or used as a multicast-broadcast single frequency network (MBSFN) subframe for at least some WTRUs, the subframe can be configured or used as a special subframe for at least some WTRUs (e.g., other WTRUs).

[0076] A WTRU can determine a power or energy for a transmission based on one or more of a path loss, resources allocated for the transmission in time or frequency, an expected received power, a power control command, a static parameter, or a semi-static parameter, among others. The static or semi-static parameter can be provided by a base station or other network resource.

[0077] A parameter, power control formula, or power control procedure can be determined based on LTE or Long Term Evolution-Advanced (LTE-A) network specifications. A power or energy for each transmission in a set of transmissions can be determined prior to the actual transmission, and one or more transmission powers can be adjusted or scaled prior to the transmission. For example, if the transmission or a set of simultaneous transmissions would cause a WTRU to exceed a maximum power limit, the transmission power(s) can be adjusted or scaled.

[0078] A WTRU can calculate a channel power without regard to or substantially independent of a maximum power or energy constraint. A WTRU can adjust a channel power or a calculated channel power such that a sum of powers for a set of channels that a WTRU can transmit or is scheduled to transmit in, for example, a subframe, does not exceed a maximum power. For channels with adjusted power, the adjusted power can be used when the WTRU transmits the channels. For other channels, the calculated power can be used when the WTRU transmits the channels.

[0079] For a maximum allowed transmit power / energy or a configured maximum output power (e.g., P CMAXIn some aspects, the power can depend on at least one of a power class of the WTRU, a power limit signaled by a base station, or an allowable power reduction of the WTRU. As an example, the allowable power reduction of the WTRU can be based on signals to be transmitted by the WTRU so as not to exceed out-of-band emission requirements or permitted values or classes.

[0080] If the WTRU has multiple serving cells, the WTRU can have a maximum allowed transmission power or a configured maximum output power P CMAXc .

[0081] As an example, the WTRU can determine the power for a channel (e.g., an UL channel) available for it to transmit, or the power for a set of channels (e.g., UL channels configured to be transmitted in a subframe). The WTRU can determine the power for the channel so as to satisfy at least one of (i) a sum of channel powers for a serving cell, e.g., to be transmitted by the WTRU in a subframe, does not exceed a P CMAXc for that serving cell; or (ii) a sum of channel powers for some, all, or substantially all of the serving cells on which the WTRU fully or at least partially transmits in a subframe does not exceed a P CMAX .

[0082] If the WTRU determines that it can exceed the maximum power in a subframe or TTI, the WTRU can adjust the power of one or more channels. The adjustment can be in accordance with a relative priority of logical or physical channels.

[0083] If the WTRU has serving cells belonging to different eNodeBs or schedulers, there can be constraints related to power allocation. Such constraints can be relative to power split among eNodeBs or schedulers. The transmission performed by the WTRU can have a minimum guaranteed power (MGP), where the power (MGP) is a percentage of P CMAX . For example, if the transmission is performed in the same, at least partially overlapping, or substantially overlapping subframes, the WTRU can consider the MGP of each eNodeB in addition to channel priority, e.g., in determining which channel power or channel powers need to be adjusted.

[0084] The WTRU can calculate, determine, or report a PH. The PH for a serving cell c (PHc) can be calculated as a difference between a calculated power of the WTRU and a maximum power of the WTRU. The maximum power of the WTRU can be a maximum output power configured for the WTRU, e.g., P CMAX,cThe computed power of the WTRU (e.g., Pcomputed unconstrained,c) can be the power computed without or prior to taking into account one or more constraints. As an example, the constraints can be imposed on the transmission power by the maximum power of the WTRU or the power allocation of a higher priority channel.

[0085] The PH of a serving cell or component carrier (CC) c in a TTI or subframe i can be expressed by equation (5): PHc(i) = P CMAX ,c(i) - Pcomputed unconstrained,c(i) equation (5) As an example, for a TTI, subframe, LTE / LTE-A TTI, or LTE / LTE-A subframe in which there is PUSCH and no PUCCH transmission or PUCCH format transmission, the PH can be expressed as: PH type1,c (i) = P CMAX,c (i) - {10 log 10 (M PUSCH,c (i)) + P O_PUSCH,c (j) + a c (j) · PL c + Δ TF,c (i) + f c (i) equation (6) M PUSCH,c (i) can be the bandwidth of the PUSCH resource allocation and can be expressed in terms of the number of resource blocks (RBs) in effect in TTI or subframe i and serving cell c. P O_PUSCH,c (j) can be the component P O_NOMINAL_PUSCH,c (j) provided by higher layers for j = 0 and 1. P O_UE_PUSCH,c (j) can be the sum of P O_NOMINAL_PUSCH,c (j) for j = 0 and 1 provided by higher layers for serving cell c. For one or more PUSCH transmissions (retransmissions) corresponding to a semi-persistent grant, j can be 0, for one or more PUSCH transmissions (retransmissions) corresponding to a dynamically scheduled grant, j can be 1, and for one or more PUSCH transmissions (retransmissions) corresponding to a random access response grant, j can be 2. For j = 2, the value of P O_UE_PUSCH,c (j) can be determined based on the outcome of the random access procedure, and P c (j) can be 0. The parameter a c (j) can be a parameter provided by higher layers or can be a fixed value. PL TF,c(i) can be a number of code blocks, a size of each code block, a number of channel quality indicators (CQI) or precoding matrix indicators (PMI) bits to be transmitted, and a number of resource elements, calculated by the WTRU based on parameters provided by higher layers or one or more of the following. c (i) can be a power control accumulation term, where the accumulation term can be an accumulation of transmit power control (TPC) commands (e.g., TPC commands for PUSCH on CC c).

[0086] PHR can be triggered or transmitted periodically, e.g., based on a certain period or periodicity. The periodicity or period can be configurable. PHR can be triggered by an event or transmitted based on occurrence of an event. Triggering events for PHR can include a path loss change, e.g., a path loss change of a serving cell. Triggering events for PHR can also include a power backoff change, which can be attributed to power management such as a serving cell. Triggering events for PHR can also include expiration of a timer, e.g., a periodic timer. For a change, e.g., a change that can trigger PHR, the change can include crossing or exceeding a threshold. Triggering events for PHR can also include activation of a secondary cell (SCell) of a WTRU, e.g., a SCell of a medium access control (MAC) entity of a WTRU configured with UL. Serving cell change can also be a triggering event. In examples and embodiments described herein, WTRU and MAC entity can be used interchangeably.

[0087] Further, a triggering event can depend on expiration of a timer, such as a prohibit timer, which can be used to limit the frequency of PH report transmission. A triggering event can depend on availability of UL resources for transmission of PHR. A WTRU can transmit PHR upon occurrence of at least one triggering event. A WTRU can transmit PHR when it has an UL grant or allocation, such as for new data transmission.

[0088] Transmission of a request, grant, HARQ feedback, or data can be performed in accordance with timing of a block, such as a TTI or a subframe. Processing time can be proportional to transmission block (TB) size.

[0089] Short TTI (sTTI) can be used for reduced latency. For shorter TTI length, e.g., TTI length with duration of one or a few symbols, physical channels designed based on one TTI length, e.g., 1 ms, can not be optimized or can not work properly. If TTI of a control channel, such as an UL control channel, is shortened or the number of symbols available for the control channel is reduced, performance of the control channel can be impacted.

[0090] A WTRU can perform multiple transmissions that can overlap or be concurrent in time. In any example given herein, overlap or concurrency in time can refer to partial overlap, substantial partial overlap, full overlap, or substantially full overlap, etc. When the transmissions use the same TTI, the overlap of the transmissions can occur at the beginning or end of the transmissions. As an example, the overlap can be known in advance of the two transmissions due to the scheduling of the two transmissions being within + / - ½ TTI of each other.

[0091] If the maximum power or energy is exceeded during the transmission overlap, the power or energy of one or more of the transmissions can be adjusted, e.g., scaled, to avoid exceeding the maximum power during the overlap. For example, if the overlap exceeds a threshold, e.g., a duration of one symbol, the adjustment can apply to substantially the entire TTI of the transmission. As an example, if the overlap is less than the threshold or less than or equal to one symbol, the adjustment can apply to the portion of the overlap.

[0092] When the transmissions use different TTIs, the transmission overlap can not occur at the beginning or end of the transmissions. An sTTI transmission can occur, as an example, at any point in a longer TTI transmission. In addition, the overlap can not be known in advance of all of the two transmissions. For example, the scheduling of an sTTI transmission can not be provided or known prior to the start of a long TTI transmission.

[0093] In examples and embodiments herein, low latency transmissions, latency-reduced transmissions, and short or sTTI transmissions are interchangeable with each other. In examples and embodiments herein, TTI and TTI length are interchangeable with each other.

[0094] A latency-reduced transmission can use a reduced TTI (rTTI) or sTTI. The rTTI or sTTI length can refer to a first TTI length that is shorter than a second TTI length, where the second TTI length can be a preconfigured, predetermined, typical, normal, regular, or legacy TTI length. The second TTI length can be 1 millisecond, 14 symbols, or 14 SC-FDMA symbols. A regular, normal, or legacy transmission can use or can be configured to use a regular TTI. In examples and embodiments herein, typical, normal, regular, and legacy are interchangeable with each other. Normal can also be used to mean non-short.

[0095] An sTTI length can be defined or correspond to Ns OFDM or SC-FDMA symbols, where Ns can be less than the number of OFDM or SC-FDMA symbols for a normal TTI. For example, Ns can be less than 14. A SC-FDMA symbol can be an uplink modulation symbol, a modulation symbol, or a sidelink symbol. One or more sTTI resource units or time units can be used, configured, predefined, or determined in a period. A resource unit can be a time unit. The period can be one or more subframes, radio frames, slots, or symbols, and can be referred to herein as an sTTI time window. An sTTI resource can correspond to a set of one or more time units, where a time unit can be at least one of a time sample, a symbol, or a slot. Herein, sTTI resource unit, sTTI, sTTI resource, and sTTI time resource are used interchangeably.

[0096] An sTTI time window can be determined based on a value that can be defined, predefined, fixed, or configured. The value can be referred to as NsTTI. The unit of NsTTI can be in milliseconds. An sTTI time window can be determined based on a mode of operation, such as TDD or FDD. An sTTI time window can be determined based on an sTTI length, for example, an sTTI time window can be a multiple of an sTTI length. An sTTI time window can be determined based on one or more system parameters, such as a cell ID or a system bandwidth. An sTTI time window can be determined based on a subframe number (SFN) or a super SFN, among others. An sTTI time window can be determined based on a TTI length of a normal subframe.

[0097] For a control channel, such as a downlink control channel, the channel can be transmitted in the first Nsym symbols in an sTTI time window. Nsym can be an integer greater than or equal to 1. One or more sTTIs or a number of sTTIs that can be used for a gap, such as a DL-UL gap, can be indicated by at least one of a control channel, a signal, or an indication, among others. A control channel can be or can include a signal or an indication, where the signal or the indication can indicate one or more sTTIs or a number of sTTIs that can be used for a gap, such as a DL-UL gap. The signal or the indication can be a predefined, configured, or known signal or indication. The number of sTTIs can be an integer greater than or equal to 1. As an example, for a direction switch that does not require or use a gap, such as a UL-DL switch, the number can be 0.

[0098] FIG. 5is an example of sTTI gap indication that can be used to indicate sTTI resource configuration or usage for uplink, downlink, and gap. sTTI#3 can be indicated as a gap sTTI 514 within, for example, DL control 502, in which a switch 510 between DL and UL can occur. A first set of sTTI resources can be sTTI#0, #1, #2, and can be used as DL sTTI 512. A second set of sTTI resources can be sTTI#4, #5, #6, and can be used as UL sTTI 516. In this example, sTTI window 506 can be a subframe, and sTTI time resource unit 508 can be a number of symbols, for example, 2. sTTI time window 506 can be applied on bandwidth 504. The sTTI window and sTTI time window can be used interchangeably.

[0099] A DL-UL gap can be a gap between a DL direction and a UL direction that can be used for switching, for example, to switch a radio or RF front end from a DL direction to a UL direction. In examples and embodiments herein, DL-UL gap, gap, DL-UL switching gap, DL to UL gap, TDD switching gap, switching gap, gap sTTI, sTTI gap, GP, TDD GP, TDD gap can be used interchangeably. In addition, one or more sTTI time windows can be associated with a control channel or PDCCH that can carry one or more downlink control information (DCI), for example, legacy PDCCH.

[0100] A first set of sTTI resources in or existing in a sTTI window can be determined or configured to be a set of downlink sTTI resources or DL sTTI. A second set of sTTI resources in the sTTI window, for example, in the same sTTI window, can be determined or configured to be a set of uplink sTTI resources or UL sTTI. The first set of sTTI resources and the second set of sTTI resources can be non-overlapping or mutually exclusive. One or more sTTI resources can be indicated as a gap within the sTTI window. The location of the gap can determine the first set of sTTI resources and the second set of sTTI resources.

[0101] If more than one sTTI resource is indicated as a gap, the sTTI resources indicated as a gap can be consecutive or substantially consecutive in time. The number of sTTI resources used, determined, selected, or configured for a gap can be based on higher layer signaling, one or more system parameters, dynamic indication from a control channel, or operational mode, among others. The number of sTTI resources for a gap can be determined, configured, or indicated in a cell-specific manner. Cell-specific higher layer signaling can be used to indicate the number of sTTI resources available for a gap.

[0102] The number of sTTI resources for a gap can be determined, configured, or indicated in a WTRU-specific manner. A timing advance value for a WTRU can be used to configure or determine the number of sTTI resources for a gap. WTRU-specific RRC signaling can be used to configure or determine the number of sTTI for a gap. DCI associated with a WTRU-ID or a cell radio network temporary identifier (C-RNTI) can indicate the number of sTTI resources for a gap. The DCI can be received from a base station.

[0103] The number of sTTI resources for a downlink can be indicated. The number of sTTI resources for a downlink can determine the index of sTTI resources for a gap. For example, if three sTTI resources can be determined, used, or indicated for a downlink transmission or as DL sTTI, the fourth sTTI resource in a sTTI time window can be the starting sTTI resource for a gap. If one sTTI resource is used for a gap, the fourth sTTI resource can be used as a gap, and the fifth sTTI resource can be the first sTTI resource for an uplink transmission, e.g., UL sTTI.

[0104] One or more sTTI can be or can be used as a switching point, e.g., a DL-UL switching point or a UL-DL switching point. The one or more sTTI that can be used as a switching point can be indicated or identified by at least one of the following: a control channel, a signal or indication, etc. For example, a control channel can be or can include a signal or indication that indicates one or more sTTI as a switching point. The signal or indication can be a pre-defined, configured, or known signal or indication. A switching point can be the beginning of a gap, e.g., a gap for a DL-UL or UL-DL switching point. A switching point can also be the beginning of a sTTI in which a direction can switch from a first direction to a second direction. A switching point can be the beginning of a sTTI in which a gap is not needed or used, e.g., not needed or used for a WTRU, between a first direction and a second direction.

[0105] Further, a switching point can be the beginning of a gap in which a gap size can be zero or substantially zero. An indication for a sTTI gap can include an indication for a switching point, e.g., a sTTI or a gap size for a switching point. A gap size can be a number of sTTI, where the sTTI can be consecutive sTTI. A gap size of zero can indicate or can be used to indicate a switching point. Also, a gap size of zero or no indication for a gap size can indicate or can indicate a switching point without a gap. In examples and embodiments herein, a switching point and a gap can be interchangeable.

[0106] A plurality of sTTI gaps can be indicated in an sTTI window. A first sTTI gap can be used to determine a time location of a DL to UL switch and a second sTTI gap can be used to determine a time location of an UL to DL switch. The time location can be or can include one or more sTTI resources. The one or more sTTI resources that can be indicated as the first gap will not be used for one or more uplink or downlink transmissions. For example, a WTRU can use one or more sTTI resources in the gap as a switch time, for example, from DL to UL. The number of sTTI resources used for the gap can be indicated by higher layer signaling, predefined, configured, semi-statically configured, or locally statically configured. The one or more sTTI resources indicated as the second gap can be used for uplink or downlink transmissions. A WTRU can receive or transmit signals in the one or more sTTI resources used as the second gap. The number of sTTI resources used for the gap can be indicated or known, for example, as 0 or substantially 0.

[0107] FIG. 6 is an example of a multi-gap sTTI indication. DL control 602 can include at least a portion of a control channel used to send control information to a WTRU. sTTI #2 or sTTI resource #2 can be indicated as a first gap 616 and sTTI #5 or sTTI resource #5 can be indicated as a second gap. sTTI window 606 can be one or more subframes and sTTI time resource unit 608 can be any number of symbols, such as on bandwidth 604. As an example, sTTI window 606 can be a subframe and sTTI time resource unit 608 can be a number of symbols, such as on bandwidth 604, for example, the number is 2.

[0108] In FIG. 6 , the set of sTTI resources for one or more downlink transmissions 614 or 628 and the set of sTTI resources for one or more uplink transmissions 624 can be determined based on the location of the gap sTTI resources, for example, the location of sTTI resources for the first gap 610 and sTTI resources for the second gap 612. The sTTI resources indicated as the first gap can be indicated with a gap size of 1 sTTI 608. The sTTI resources indicated as the second gap can be indicated with no gap size or a gap size of 0 or substantially 0. As FIG. 6 b shows, as an example, when the previous sTTI resource or the resource before the gap sTTI is used as an uplink sTTI (e.g., 624), the sTTI resources indicated as the second gap can be used as downlink sTTIs.

[0109] In the examples given here, UL sTTI resource configuration using TDD GP is available. In one embodiment, the GP in a subframe can be used for sTTI transmission or reception. For example, one or more UL sTTI resources can be allocated in the GP of a particular subframe.

[0110] FIG. 7 is an example of sTTI resource configuration in the GP of subframe 702. The subframe can be a particular subframe. The WTRU can be configured, directed, or instructed to use a first TTI operation 704, which can be a normal TTI operation. The WTRU can determine to use the first TTI operation 704. For example, DwPTS 706, GP 708, and UpPTS 710 can be determined by the WTRU based on a subframe configuration, such as subframe configuration #0, which can be received from higher layer signaling, such as broadcast signaling, for example. The subframe configuration can be a particular subframe configuration. The WTRU can assume that no downlink signal will be received or no uplink signal will be transmitted in the symbols available for GP 708.

[0111] The WTRU can or can be configured to, can determine, or can be instructed to use sTTI resources or perform sTTI transmission. The WTRU can use one or more symbols of the GP determined based on a subframe configuration, such as configuration #0, as UpPTS or sTTI resources.

[0112] For example, one or more symbols of the GP 708 that can be determined based on a subframe configuration, such as subframe configuration #0, can be referred to as GP symbols. A short or sTTI GP (sGP) 714 or 720 can be determined based on the number of GP symbols used for sTTI resources. The sGP can be used for one or more of the following: a guard period for sTTI operation, sTTI transmission scheme, sTTI operation mode, or DL-UL switching for sTTI transmission, among others. In addition, one or more GP symbols can be used as additional symbols for DwPTS or UpPTS. For example, 7 symbols of GP 708 can be used as or determined to be UpPTS 716. In FIG. 7 In the example of FIG. 7B, the process of using a portion of the GP for UpPTS is referred to as type 1 sTTI operation 712. The sTTI resources can be or can include one or more symbols in the UpPTS or the UpPTS extended to include one or more GP symbols, such as all symbols.

[0113] In subframe 702, one or more GP symbols can be used, determined, or indicated as sTTI resources that are substantially separate from the DwPTS or UpPTS. This configuration can be identified as type 2 sTTI operation 718. For a GP symbol that can be used, determined, or indicated as sTTI, the GP symbol can be referred to as an sTTI symbol. The sTTI symbol can be used for one or more of sTTI UL, sTTI DL, or gap transmission. In FIG. 7 In the example shown, 7 GP symbols 708 can be used or determined as sTTI resources 722.

[0114] For the number or location of sTTI symbols within a GP, such as GP 708 of subframe 702, it can be determined or predetermined based on at least one of the following: a received subframe configuration, using sTTI for UL sTTI, or using sTTI symbols for DL sTTI. Table 3 shows one example of possible sTTI symbol configurations. The sTTI symbol configuration can be based on a subframe configuration, such as a particular subframe configuration. For the location, such as the time location, of sTTI symbols, the location can be determined based on the processing of using sTTI resources as DL sTTI or UL sTTI. Table 3

[0115] If sTTI symbols are used for UL sTTI, the sTTI symbols can be located on the last N UL GP symbols. If sTTI symbols are used for DL sTTI, the sTTI symbols can be located on the first N DL GP symbols. If sTTI symbols are used for a combination of DL sTTI and UL sTTI, a first set of sTTI symbols can be used for DL sTTI and a second set of sTTI symbols can be used for UL sTTI.

[0116] The number of sTTI symbols within a GP, such as GP 708, can be configured by higher layer signaling. One or more parameters associated with sTTI operation can be signaled, and the number of sTTI symbols within a GP can be indicated from the one or more parameters. For the number of sTTI symbols (e.g., the number of sTTI symbols within a GP), the number can be determined based on a particular subframe configuration, one or more parameters associated with sTTI operation, or one or more system parameters, which can be physical cell identity (cell ID), virtual cell ID, system bandwidth, and frame structure, as examples. For the number of sTTI symbols (e.g., the number of sTTI symbols within a GP), the number can be determined based on a WTRU-specific parameter, such as C-RNTI or dynamically indicated, among others.

[0117] The number of sTTI symbols can be determined based on a timing advance value for the WTRU or used, indicated, or determined by the WTRU. For example, for a WTRU that can be indicated, determined, or use a first timing advance value, the WTRU can use a first number of sTTI symbols in a GP (e.g., in GP 708). For a WTRU that can be indicated, determined, or use a second timing advance value, the WTRU can use a second number of sTTI symbols in a GP (e.g., in GP 708).

[0118] A WTRU can receive one or more downlink sTTI signals, such as a short or sTTI physical downlink shared channel (sPDSCH) or a short or sTTI physical downlink control channel (sPDCCH), in sTTI resources. A WTRU can transmit one or more uplink sTTI signals, such as a short or sTTI physical uplink control channel (sPUCCH) or a short or sTTI physical uplink shared channel (sPUSCH), in sTTI resources. A WTRU can also transmit or receive one or more reference signals associated with DL or UL sTTI signals in sTTI resources.

[0119] FIG. 8 is an example of sPUCCH resource configuration provided or used in a downlink subframe or physical resource block (PRB) 800. In FIG. 8In particular embodiments, the first time slots 802 can correspond to even time slot numbers in a radio frame, e.g., time slot numbers ns mod 2 = 0 in a radio frame, and the second time slots 804 can correspond to odd numbered time slots in a radio frame, e.g., ns mod 2 = 1. In one example, one time slot can be 7 symbols on 12 subcarriers. The downlink subframe or PRB 800 can include one or more of a CRS 806, a PDCCH 808, a PDSCH 810, a sPDCCH / sPDSCH 812, a sGP 814, and a sPUCCH 816.

[0120] One or more DL symbols in a subframe can be used as, configured as, or determined to be UL sTTI resources. A DL symbol can be a symbol in a subframe that can be configured or used for UL, e.g., for at least one or some WTRUs. A DL symbol without cell-specific reference signals can be used as or determined to be a UL sTTI resource. The last N UL DL symbols in a subframe can be used as, determined to be, or configured to be UL sTTI resources. The N UL may be determined based on a number of antenna ports used for cell-specific reference signals. In one example, if the number of CRS ports can be four, e.g., antenna ports 0 / 1 / 2 / 3, then the N UL may be a first number, e.g., 2. If the number of CRS ports can be one or two, then the N UL may be a second number, e.g., 5.

[0121] The N UL may be determined based on a sTTI length used, determined, indicated, or configured for an associated downlink sTTI transmission. The N UL may also be determined in accordance with at least one of a system parameter, a subframe number, a SFN, a super-SFN, a WTRU-specific parameter, a WTRU-ID, a number of OFDM symbols available for a PDCCH region, e.g., a legacy PDCCH region, or a time location of an associated downlink sTTI transmission, etc.

[0122] At least two consecutive DL symbols can be used as UL sTTI resources, and the one or more DL symbols in front can be used as sGPs. FIG. 8An example of sPUCCH resource configuration using the last two downlink symbols is shown. The first symbol of the sTTI resource can be used for sGP and the second symbol of the sTTI resource can be used for sPUCCH 816 transmission. One or more sPUCCH transmissions can include one or more HARQ-ACK transmissions or reports and can be associated with one or more sPDSCH transmissions. The one or more sPDSCH transmissions can be located in the same subframe or in the previous subframe. The sPUCCH can be used for one or more HARQ-ACK transmissions corresponding to one or more associated sPDSCH transmissions.

[0123] In addition, sPUCCH can be used to transmit a scheduling request for uplink resources related to latency reduced transmissions.

[0124] sPUCCH can be defined, determined, configured, or used to provide an indication of special type of data in the buffer. The special type of data can include latency reduced data, emergency data, ultra-low latency data, short TTI data, or ultra-reliable data, among others.

[0125] sPUCCH can be defined, determined, configured, or used to communicate (e.g., transmit) CSI for one or more sTTIs that are configured, determined, indicated, or used. The CSI can include CQI associated with one or more sTTI resources. The CSI can include one or more preferred sTTI resources for one or more downlink or uplink sTTI transmissions. The CSI can include CSI associated with one or more antenna transmissions including, but not limited to, a precoding matrix indicator (PMI), a rank indicator (RI), a precoding type indicator (PTI), a CSI-RS index (CRI), or a quasi-collocation indication (QCI), among others. sPUCCH can be defined, determined, or used to provide or communicate uplink reference signals related to uplink channel measurements.

[0126] One or more sPUCCH formats, types, structures, or resources can be defined, configured, determined, or used for latency reduced transmissions or to improve uplink performance. sPUCCH format, sPUCCH type, sPUCCH structure, sPUCCH resource, and resources used for sPUCCH transmission can be used interchangeably, consistent with embodiments and examples herein.

[0127] The sPUCCH type can be determined or identified based on one or more of the following: TTI length (which can be in number of uplink symbols) of one or more sPUCCH transmissions, sTTI length of one or more associated downlink transmissions or channels such as sPDCCH or sPDSCH, one or more DCI, higher layer signaling, dynamic indication, one or more reference signal locations within one or more sPUCCH, transmission power level or maximum transmission power level or one or more sPUCCH transmissions, reference signal overhead or density of one or more sPUCCH transmissions, etc. The sPUCCH type can also be determined or identified based on number of frequency resources used for one or more sPUCCH transmissions, where the number of frequency resources can be number of PRBs, number of tones or number of subcarriers. The sPUCCH type can also be determined or identified based on a set of frequency locations, such as even numbered subcarriers or odd numbered subcarriers. The sPUCCH type can also be determined or identified based on a type of sequence used, such as Zadoff-Chu sequence, Golay sequence or Gold sequence, etc. In addition, the sPUCCH type can also be determined or identified based on a modulation scheme used, which can be binary phase shift keying (BPSK), quadrature PSK (QPSK), pi / 2-BPSK, pi / 4-QPSK or a set of modulation schemes used, as examples. For instance, a first set of modulation schemes can be BPSK and QPSK, and a second set of modulation schemes can be pi / 2-BPSK and pi / 4-QPSK.

[0128] Further, the sPUCCH type can be determined or identified based on a scheme used for transmitting one or more HARQ-ACK transmissions or reports, such as a subcarrier-based scheme, a cyclic shift-based scheme, or a frequency hopping scheme. In a HARQ-ACK scheme, one set of subcarriers can be determined for one or more HARQ-ACK transmissions or reports. As an example, a first set of subcarriers can be used or selected for one or more ACK transmissions or for reporting ACK, and a second set of subcarriers can be used or selected for one or more NACK transmissions or for reporting NACK. In another HARQ-ACK scheme, a set of cyclic shifts of a sequence can be used for one or more HARQ-ACK transmissions. As an example, a first cyclic shift index can be used or selected for one or more ACK transmissions or for reporting ACK, and a second cyclic shift index can be used or selected for one or more NACK transmissions or for reporting NACK. In another HARQ-ACK scheme, a set of frequency hopping patterns can be used for one or more HARQ-ACK transmissions. As an example, a first frequency hopping pattern can be used or selected for one or more ACK transmissions or for reporting ACK, and a second frequency hopping pattern can be used or selected for one or more NACK transmissions or for reporting NACK.

[0129] One or more sPUCCH resources or types can be configured, defined, or used in a sTTI time window, such as a subframe. One or more sPUCCH resources can be dedicated for use by one or more WTRUs. The sTTI time window can be fixed, predefined, preconfigured, or predetermined to be a particular value. For example, the sTTI window can be predefined to be a normal TTI length or have a length of 1 millisecond. Further, the sTTI time window can be determined based on a sTTI length or a multiple (e.g., an integer multiple) of a sTTI length. For example, if a sTTI length is referred to as L sTTI , and N sTTI is a positive integer used to determine the sTTI length, then the sTTI window length can be determined based on L sTTI x N sTTI The sTTI time window can also be determined based on a downlink sTTI time window, higher layer signaling, RRC signaling, or dynamic signaling from a downlink physical channel, among other examples.

[0130] The sPUCCH type can be determined based on a coverage level that can be configured or determined. The coverage level can be configured by higher layer signaling for at least one of a downlink control channel, a downlink data channel, an uplink control channel, and an uplink data channel, but is not limited thereto. As an example, the coverage level can be determined based on a coverage level of one or more physical random access channel (PRACH) transmissions selected or determined by the WTRU. In addition, the sPUCCH type can be determined based on a downlink measurement level. For example, the sPUCCH type can be determined using a predefined or configured threshold. The downlink measurement can include at least one of a reference signal received power (RSRP), a reference signal received quality (RSRQ), and a CQI.

[0131] The sPUCCH type can be determined based on an sTTI length of an associated DL channel. The sTTI length used for sPDCCH or sPDSCH can determine the sPUCCH type. The sPUCCH type can be determined based on higher layer signaling. The sPUCCH type can be indicated implicitly or explicitly by higher layer signaling. The sPUCCH type can be determined based on a dynamic indication. A DCI associated with a sPUCCH transmission can indicate or determine the sPUCCH type for the sPUCCH transmission.

[0132] The sPUCCH type can be determined based on a number of sPDSCHs that can be associated with one or more sPUCCH transmissions. For example, a first sPUCCH type or format can be used if a single sPDSCH transmission can be associated with one or more sPUCCH transmissions such as for one or more HARQ-ACK transmissions or reports. A second sPUCCH type or format can be used if more than one sPDSCH transmission can be associated with a sPUCCH transmission such as for a HARQ-ACK transmission or report.

[0133] The sPUCCH type can be determined based on a number of HARQ-ACK bits of one or more sPDSCHs associated. For example, a first sPUCCH type or format can be used if the number of HARQ-ACK bits is less than or equal to a threshold value that can be defined, predefined, or configured. A second sPUCCH type or format can be used if the number of HARQ-ACK bits is greater than a threshold value that can be defined, predefined, or configured. One or more threshold values can be used with one or more sPUCCH types or formats.

[0134] An sPUCCH can be repeated or iterated in one or more sTTI resources. A higher layer signal can indicate a number of repetitions for one or more sPUCCH transmissions. For example, an sPUCCH type and a number of repetitions or iterations for sPUCCH transmissions can be configured by a higher layer signaling such as broadcast or RRC signaling. The number of sPUCCH repetitions can be predefined, configured, dynamically indicated from an associated DCI, or can be determined based on sTTI resources used for sPUCCH transmissions.

[0135] The number of repetitions for sPUCCH transmissions can also be determined based on a number of repetitions for associated sPDSCH or sPDCCH transmissions. A modulation and coding scheme (MCS) level of one or more associated sPDSCH transmissions can determine a number of sPUCCH repetitions. For example, if a higher MCS level is used for associated sPDSCH transmissions, a number of sPUCCH repetitions can be lower. If a lower MCS level is used for associated sPDSCH transmissions, a sPUCCH with a higher number of repetitions can be used. The number of repetitions for one or more sPUCCH transmissions can be determined based on an aggregation level of short or sTTI control channel elements (sCCEs) available for associated sPDCCH. For example, if a higher number of sCCE aggregation levels is used for associated sPDCCH, a number of sPUCCH repetitions can be relatively higher. If a lower sCCE aggregation level is used for associated sPDCCH, a sPUCCH with a lower number of repetitions can be used. In the embodiments and examples described herein, sPUCCH can be replaced by sPUSCH, and vice versa.

[0136] An sPUSCH can be defined, determined, configured, or used for one or more uplink data transmissions. For example, one or more sPUSCH types, structures, or resources can be defined, configured, determined, or used herein to reduce transmission latency or improve uplink performance. In the examples and embodiments herein, sPUSCH types, sPUSCH structures, and sPUSCH resources can be replaced by each other.

[0137] The sPUSCH type can be determined based on the sTTI length of one or more sPUSCH transmissions, which can be the number of uplink symbols. The sPUSCH type can be determined based on the sTTI length of the associated downlink control channel for the uplink grant, the sTTI length of the associated sPDCCH carrying the uplink grant, one or more reference signal locations within the one or more sPUSCH transmissions, reference signal overhead or density of the one or more sPUSCH transmissions in a PRB, a set of frequency locations, such as a subset of subcarriers, available for the one or more PUSCH or sPUSCH transmissions in a PRB, or a modulation scheme, among other examples. As an example, the subset of subcarriers can be even numbered subcarriers or odd numbered subcarriers.

[0138] One or more sPUSCH resources or types can be configured, defined, or used in an sTTI time window (e.g., a subframe), and one or more sPUSCH resources can be dedicated for use by one or more WTRUs.

[0139] sPUSCH link adaptation can be provided or used. The sPUSCH type or the number of repetitions of the sPUSCH transmission can be determined based on a coverage level. The coverage level can be configured or determined. The coverage level can be configured by higher layer signaling for at least one of a downlink control channel, a downlink data channel, an uplink control channel, or an uplink data channel, among other examples. In addition, the coverage level can be determined based on a coverage level selected or determined for one or more PRACH transmissions, which can be selected or determined by a WTRU, as an example.

[0140] The sPUSCH type or the number of repetitions of one or more sPUSCH transmissions can be determined based on a downlink measurement level. For example, a pre-defined or configured threshold can be used to determine the sPUSCH type or the number of repetitions of one or more sPUSCH transmissions. The downlink measurement can include at least one of an RSRP, an RSRQ, or a CQI, among other examples. The sPUSCH type or the number of repetitions of one or more sPUSCH transmissions can be determined based on the sTTI length of the associated downlink channel.

[0141] The sTTI length for sPDCCH or sPDSCH can determine the sPUSCH type or the number of repetitions of one or more sPUSCH transmissions. The sPUSCH type or the number of repetitions of one or more sPUSCH transmissions can be determined based on higher layer signaling, dynamic indication, or DCI associated with the one or more sPUSCH transmissions, among others. The sPUSCH type or the number of repetitions of sPUSCH transmissions can be implicitly or explicitly indicated from higher layer signaling. The DCI associated with sPUSCH transmissions can indicate the sPUSCH type or the number of repetitions of sPUSCH transmissions. A transport block size (TBS) can be indicated in the associated DCI for sPUSCH scheduling, and the transport block size can determine or can be used to determine the sPUSCH type or the number of repetitions of one or more sPUSCH transmissions. An MCS level can be indicated in the associated DCI for sPUSCH scheduling, and the MCS level can determine or can be used to determine the sPUSCH type or the number of repetitions of one or more sPUSCH transmissions. The sCCE aggregation level of sPDCCH for sPUSCH uplink grant can determine or can be used to determine the sPUSCH type or the number of repetitions with respect to one or more sPUSCH transmissions (e.g., with respect to one or more granted sPUSCH transmissions).

[0142] FIG. 9 is an example of a 2-symbol short or sTTI PUCCH (sPUCCH) 900, FIG. 10 is an example of a 3-symbol sPUCCH 1000, and FIG. 11 is an example of a 4-symbol sPUCCH 1100. The sPUCCH 1000 or 1100 can utilize a cover code over the r1 sequence when interference mitigation is desired. The sPUCCH can use an UL reference signal r2 902 and a number of symbols for transmitting 1 or 2 bits of information, such as HARQ feedback 912. The HARQ feedback 912 can be modulated with BPSK or QPSK, among others, and can be combined with a sequence r1 916 through a multiplication operation 913. The output of the multiplication operation 914 can be processed through an inverse fast Fourier transform (IFFT) 918 and can be mapped to resources on a symbol 920.

[0143] At 904, the UL reference signal r2 902 can be multiplied by 1. The output of the multiplication operation 904 can be processed by an inverse fast Fourier transform (IFFT) 906 and can be mapped to resources on the symbol 920. Alternatively, the multiplication at 904 can be skipped and the UL reference signal r2 902 can go directly to the IFFT 906. The sequences r1 916 and r2 902 can be sequences or sequence pairs with desirable correlation properties, such as Zadoff-Chu (ZC) or Golay. For a ZC-based configuration, the sequences r1 916 and r2 902 can be based on different root values (or indices), or can be based on different cyclic shifts of the same root value (or index). The sPUCCH 900, 1000, or 1100 can be mapped on m PRBs. i The sequence length of the sequence can be set to cover 12m subcarriers.

[0144] The variable n 910 and n±i, such as n±1 922, can indicate that the relative position of the mapping of the UL reference signal r2 902 can be located in time before or after the symbol carrying the HARQ feedback 912. As an example, the position of the UL reference signal can be placed or moved between the symbols carrying the HARQ feedback 912 in order to reduce channel estimation errors of other or further symbols.

[0145] For the sPUCCH 1000, the UL reference signal r2 1002 and a number of symbols used for transmitting 1 or 2 bits of information, such as the HARQ feedback 1012, can be used. The HARQ feedback 1012 can be modulated by using BPSK or QPSK, or the like, on two symbols. The HARQ feedback 1012 can be combined with the sequence r1 1014 by a multiplication operation 1016. The output of the multiplication operation 1016 can be processed by an IFFT 1018 and can be mapped to resources on the symbol 1010 at n±1 1020. The HARQ feedback 1012 can also be combined with the sequence r1 1014 by a multiplication operation 1013. The output of the multiplication operation 1013 can be processed by an IFFT 1022 and can be mapped to resources on the symbol 1010 at n±2 1024. At 1004, the UL reference signal r2 1002 can be multiplied by 1 and the output of the multiplication operation 1004 can be processed by an IFFT 1006 and can be mapped to resources on the symbol 1010 at n 1008. Alternatively, the multiplication at 1004 can be skipped.

[0146] For sPUCCH 1100, the UL reference signal r2 1102 and multiple symbols for transmitting 1 or 2 bits of information, such as HARQ feedback 1112, may be used. HARQ feedback 1112 may be modulated using BPSK or QPSK, etc., on three symbols. HARQ feedback 1112 may be combined with sequence r1 1114 via multiplication 1116. The output of multiplication 1116 may be processed by IFFT 1118 and may be mapped to resources on symbol 1108 at n±1 1120. HARQ feedback 1112 may also be combined with sequence r1 1114 via multiplication 1122. The output of multiplication 1122 may be processed by IFFT 1124 and may be mapped to resources on symbol 1108 at n±2 1126.

[0147] The HARQ feedback 1112 may also be combined with the sequence r1 1114 via a multiplication operation 1111. The output of the multiplication operation 1111 may be processed by an IFFT 1128 and may be mapped to resources on symbol 1108 at n±3 1130. At 1104, the UL reference signal r2 1102 may be multiplied by 1. The output of the multiplication operation 1104 may be processed by an IFFT 1106 and may be mapped to resources on symbol 1108 at n 1110. Alternatively, the multiplication at 1104 may be skipped.

[0148] Table 4 shows an example of an sPUCCH configuration for a slot with 7 symbols. The index of the (N)ACK may indicate the corresponding (s)PDSCH payload. An sPUCCH combination may represent a set of symbols used for data, such as ACK / NACK or one or more UL reference signals. This set of symbols may be an sPUCCH resource. Table 4

[0149] FIG. 12 This is an example of the signal structure of a 1-symbol sPUCCH 1200. For the sPUCCH 1200, the UL reference signal is not transmitted. The HARQ feedback information 1202 containing 1 or 2 bits can use the sequence r i 1206 to transmit. i The sequence length of the sequence can be selected by a sequence selection component 1204. The output of the sequence selection component 1204 can be processed on an IFFT 1208 and can be mapped to resources on symbol 1210 at symbol n 1212. For ZC-based configurations, the HARQ feedback information 1202 can be transmitted by selecting different roots of the ZC sequence or different cyclic shifts based on the same root value.

[0150] The sPUCCH 1200 can be mapped on m PRBs. i The sequence length of the sequence can cover or can be configured to cover 12m subcarriers. The multi-symbol sPUCCH can rely on one or more transmissions of multiple 1 -symbol instances. The frequency mapping of each symbol can be done on the same PRB or can hop to different PRBs.

[0151] FIG. 13 is an example of a signal structure of a multi-symbol sPUCCH without UL reference signal 1300 transmission, where the PRB i and the PRB j may be different. The HARQ feedback information 1302, which contains 1 or 2 bits, can be conveyed using the sequence r i 1304. i The sequence length of the sequence can be selected by a sequence selection component 1301. The output of the sequence selection component 1301 can be processed on an IFFT 1306 and can be mapped on the resources (n, PRB i ) 1310 on the resources on symbol 1308. The output of the sequence selection component 1301 can also be processed on an IFFT 1312 and can be mapped on the resources (n±1, PRB j ) 1314 on the resources on symbol 1308.

[0152] FIG. 14 is an example of a signal structure of a 1 -symbol sPUCCH 1400 that is repeated over several RBs. The HARQ feedback information 1402, which contains 1 or 2 bits, can be conveyed using the sequence r i 1404. i The sequence length of the sequence can be selected by a sequence selection component 1401. The output of the sequence selection component 1401 can be processed on an IFFT 1406 and can be mapped on m RBs by repetition 1408 on the resource n 1410. For this configuration, here a sequence of a certain length, e.g. length 12, can be selected and can be mapped on the m RBs of the symbol. The sequence r i may be repeated on the used RBs.

[0153] If multiple symbols are available for transmission, the selected sequence can be repeated on the m RBs of the symbol allocated for data transmission. Table 5 shows such an example, where the sequence r Table 5 Symbol n Symbol n+1 Symbol n+2 Symbol n+3 RBk r RS RS r RBk+1 r RS RS r

[0154] One or more sPUCCH combination configurations that can be provided or used can be fixed, configured, signaled, signaled by higher layer signaling, signaled dynamically, or indicated in physical layer signaling such as a DL grant or DCI, among other examples. For example, the sPUCCH combination for HARQ-ACK feedback associated with PUSCH can be indicated in the DCI for a grant or allocation of PDSCH.

[0155] The sPUCCH combination configuration can be fixed for all configured subframes or can change depending on the subframe number. The sPUCCH combination configuration can be based on the frequency location of one or more PRBs available for one or more sPUCCH transmissions or based on the subframe number. In FDD, the sPUCCH combination configuration for subframes 0 and 5 can be different than the sPUCCH combination configuration for other subframes.

[0156] As an example, a WTRU or group of WTRUs can or can be configured to use the same i-th location for sPUCCH for a fixed or semi-static sPUCCH combination configuration for substantially all time. The sPUCCH combination configuration can be dynamically signaled by reusing an existing DCI field or a new 2-3 bit DCI field.

[0157] A WTRU can use or can be configured to use a subset of the sequences for sPUCCH that can be defined or used for regular PUCCH. A WTRU can also use or can be configured to use a different set for sPUCCH operation that is not the same or overlapping with the set used for regular PUCCH.

[0158] One or more uplink short or sTTI transmissions can have a first sTTI length and one or more downlink transmissions can have a second sTTI length, where the first sTTI length and the second sTTI length can be the same or different. One or more uplink short or sTTI channels such as sPUCCH or sPUSCH can have the same or different sTTI lengths. One or more downlink sTTI channels such as sPDSCH or sPDCCH can have the same or different sTTI lengths. The terms short channel and sTTI channel can be used interchangeably.

[0159] FIG. 15is an example of short or sTTI PUSCH (sPUSCH) scheduling implemented in a communication 1500 having one or more associated short or sTTI PDCCH (sPDCCH) regions of one or more sPDCCH transmissions 1502. A WTRU can locate, transmit, monitor, or decode one or more sPDCCH candidates in a sPDCCH region or one or more transmissions. A WTRU can receive a scheduling grant for sPUSCH transmissions 1510 in one or more associated sPDCCH regions or transmissions. sPUSCH resource #1 for one or more sPUSCH transmissions 1510 can be associated with two sPDCCH regions or transmissions, such as sPDCCH #1 of subframe n and sPDCCH #2 of subframe n+k, for example. Accordingly, sPUSCH resource #2 for one or more sPUSCH transmissions 1510 can be associated with two sPDCCH regions or transmissions, such as sPDCCH #3 of subframe n+k and sPDCCH #4 of subframe n+k+1, for example.

[0160] The sTTI length of one or more sPUSCH transmissions 1510 can be configured to be longer than the sTTI length of the associated sPDSCH. A WTRU can also receive, decode, attempt to decode, or monitor for DCI for a scheduling grant for one or more sPUSCH transmissions 1510. A sPDCCH candidate can carry DCI for uplink or downlink scheduling.

[0161] FIG. 16 An example of sPUSCH association with at least one sPDCCH 1602 for HARQ-ACK reception when UL and DL sTTI lengths are different is shown. In communication 1600, one or more sPDCCH regions can be associated with sPUSCH regions for sPUSCH scheduling or one or more HARQ-ACK transmissions or reporting. For example, one or more sPUCCH transmissions of communication 1600 in sPUSCH region or transmission #0 of subframe n can be associated with sPDCCH regions or transmissions #0, #1, #2, and #3 of subframe n+2. Further, the sTTI length of sPDCCH can be longer than sPUSCH.

[0162] For one or more sPUSCH transmissions 1610, the WTRU can receive a HARQ-ACK, e.g., on a physical hybrid-ARQ indicator channel (PHICH) associated with the sPUSCH transmission. If the WTRU receives a negative HARQ-ACK or NACK, the WTRU can transmit the same transport block at a predefined or predetermined location. The WTRU can receive an uplink grant with a retransmission indication, e.g., a new data indicator. For this configuration, the new data indicator bit in the uplink grant can not be toggled, and the WTRU can retransmit the transport block in the scheduled uplink resources associated with the uplink grant, where the new data indicator bit would change from 0 to 1 or from 1 to 0 if the new data indicator bit is toggled. Otherwise, the new data indicator bit would not be toggled.

[0163] The number of sPDCCH regions associated with a sPUSCH region or one or more transmissions, sPUSCH sTTI resources, or sPUSCH sTTI can be determined based on the sTTI length of the sPDCCH and the sTTI length of the sPUSCH. For example, Nsp sPDCCH regions can be associated with a sPUSCH region. Nsp can be determined based on the sTTI length of the sPUSCH. If one or more sPUSCH regions have different sTTI lengths, Nsp can be different for one or more sPUSCH regions. For some configurations, a sPUSCH region with a shorter sTTI length can have a smaller number of associated sPDCCH regions, and a sPUSCH region with a longer sTTI length can have a larger number of associated sPDCCH regions.

[0164] Nsp can be determined based on the sTTI length of the sPDCCH or sPDCCH region or the time location of the sPDCCH region or sPUSCH region. For example, a first sPUSCH region in a sTTI time window can have a relatively larger Nsp compared to a subsequent or last sPUSCH region in the same sTTI time window. Nsp can be determined based on the SFN or super-SFN for the sPUSCH region, the sPUSCH region index within the sTTI time window, the sPUCCH type or sPUSCH type, etc.

[0165] A WTRU can monitor, attempt to decode, or receive UL DCI or DL HARQ-ACK for one or more sPUSCH transmissions in the sPDCCH region. A WTRU can monitor a subset of the Nsp sPDCCH regions for UL DCI, UL grant, uplink grant, sPUSCH scheduling DCI, or DCI for UL grant, etc. The UL DCI can include scheduling information associated with one or more sPUSCH transmissions. The UL DCI or the CRC of the UL DCI can be scrambled with a WTRU specific parameter, such as C-RNTI or WTRU-ID, etc. The size of the UL DCI can be the same as the DL DCI. A subset of the Nsp sPDCCH regions can be or can be configured to be a single sPDCCH region. A WTRU can only monitor, receive, or attempt to decode one sPDCCH region for UL DCI within the Nsp sPDCCH regions. A subset of the Nsp sPDCCH regions, such as a subset for UL DCI for a certain WTRU, can be determined based on one or more WTRU specific parameters.

[0166] A sPDCCH region within the Nsp sPDCCH regions can be determined by a WTRU according to a modulo operation of Nsp, WTRU-ID, or C-RNTI, etc. By distributing sPDCCH regions for UL DCI in a WTRU specific manner, the sPDCCH blocking probability for UL DCI can be reduced. Furthermore, if more than one sPDCCH region is included in a subset of the Nsp sPDCCH regions available to a WTRU for UL DCI, for example, the number of sPDCCH candidates that can be monitored by the WTRU can be split among the subset of sPDCCH regions.

[0167] A sPDCCH region can have a sPDCCH region index within the Nsp sPDCCH regions associated with sPUSCH resources. The index can depend on the time or frequency location of the sPDCCH region. The index can depend on its time or frequency location within the Nsp sPDCCH regions. Furthermore, a subset of the Nsp sPDCCH regions, such as a subset for UL DCI for one or more WTRUs, can be determined based on the time (or frequency) location or sPDCCH region index. As an example, a first sPDCCH region in the Nsp sPDCCH regions can be determined to be a subset of the Nsp sPDCCH regions available for UL DCI. The first sPDCCH region can be the first region in time, the region with the lowest frequency, the region with the highest frequency, or the region with the lowest index, etc.

[0168] A subset of the Nsp sPDCCH regions can be determined based on sPDCCH region index and / or system parameters, where the system parameters can include at least one of physical cell ID (PCID), slot number, subframe number, and radio frame number. For example, a modulo operation combining sPDCCH region index and PCID can be used here. In addition, the subset of the Nsp sPDCCH regions can also be determined based on sPDCCH regions that can be used, monitored, determined, or configured for DL DCI for one or more sPDSCH transmissions. For example, if a WTRU is configured or determined to monitor a subset of sPDCCH regions for DL DCI, the subset of sPDCCH regions can be the same subset used for UL DCI.

[0169] A WTRU can monitor DL DCI and UL DCI in the same sPDCCH region, transmission, or candidate set. The DL DCI can be a DCI for fallback transmission and determined based on a configured transmission scheme or mode. In one configuration, a subset of the Nsp sPDCCH regions can be determined based on the presence of a predefined signal. For example, a predefined signal can be transmitted in a first sPDCCH region and the predefined signal can indicate a subset of the Nsp sPDCCH regions for UL DCI.

[0170] sPDCCH candidates for UL DCI can be located in the Nsp sPDCCH regions. At least one sPDCCH candidate located in the Nsp sPDCCH regions can be used for UL DCI. For example, when Nsp = 1, Ntot sPDCCH candidates can be used, configured, or monitored in the sPDCCH region. As an example, when Nsp > 1, Ntot sPDCCH candidates can be divided among the Nsp sPDCCH regions. The Ntot sPDCCH candidates can be evenly distributed across the Nsp sPDCCH regions. For example, if Ntot = 16 and Nsp = 4, each sPDCCH region can include 4 sPDCCH candidates for UL grant.

[0171] A subset of sCCE aggregation levels (AL) can be monitored in a sPDCCH region. For example, if sCCE aggregation levels {1, 2, 4, 8} are used and Nsp=4, then sPDCCH candidates with sCCE AL {1} can be monitored in a first sPDCCH region and sPDCCH candidates with sCCE AL {2} can be monitored in a second sPDCCH region, and so on. The search space for each sPDCCH region (e.g., the starting sCCE number for each sCCE aggregation level) can be determined based on sPDCCH region index, WTRU-ID, a predefined number, or a hashing parameter, among other examples.

[0172] sPDCCH candidates can be transmitted within one or more of the Nsp sPDCCH regions. Further, one or more sPDCCH candidates in a search space can be repeatedly transmitted over the Nsp sPDCCH regions. The sCCEs for a sPDCCH candidate can also be distributed over the Nsp sPDCCH regions. The number of repetitions for a sPDCCH candidate within the Nsp sPDCCH regions can be determined based on a search space type, a WTRU-specific search space, a common search space, a number of sPDCCH regions Nsp, a WTRU coverage level, a configured coverage level, a determined coverage level, or a number configured by higher layers. The sCCEs can be numbered from 0 to Ncce-1 using all sCCEs configured in the Nsp sPDCCH regions. Further, a set of sCCEs can be selected, determined, configured, or used based on a search space determination.

[0173] FIG. 17 An example of association of sPUCCH for HARQ-ACK transmission 1710 with at least one short or sTTI physical downlink shared data channel (sPDSCH) is shown when the UL and DL sTTI lengths are different. In communication 1700, the sTTI length for one or more sPDSCH transmissions 1702 is relatively shorter compared to the sTTI length for sPUCCH regions #0-#4. For example, sPDSCH regions #0, #1, #2, and #3 of subframe n+1 can be associated with sPUCCH region #0. In other words, in communication 1700, the sTTI length for sPUCCH region #0 is longer than the sTTI length for sPDSCH transmissions 1702.

[0174] One or more sPDSCH regions can be associated with sPUCCH regions, resources, or transmissions for HARQ-ACK transmission. For example, in communication 1700, a WTRU can receive sPDSCH in a first sPDSCH region #1 and can receive sPDSCH in a second sPDSCH region #3, while HARQ-ACK transmission or reporting for the first sPDSCH region #1 and the second sPDSCH region #3 can be associated with sPUCCH region #0.

[0175] In communication 1700, sPUCCH #0 can be associated with one or more sPDSCHs and can include one or more sPUCCH resources. A WTRU can transmit HARQ-ACK in the uplink using sPUCCH resources in the associated sPUCCH region after receiving sPDSCH.

[0176] In a sPUCCH region, one or more sPUCCH resources can be defined, configured, determined, or indicated as at least one of a PRB index, one or more UL symbol numbers, a cyclic shift index, a tone or subcarrier index, and the like. One or more DL sTTI transmissions, such as sPDCCH or sPDSCH, can be associated with a sPUCCH region and sPUCCH resources based on a starting DL symbol, a DL sTTI transmission OFDM symbol number, a DL sTTI resource index, or a sTTI number or index in a sTTI time window, and the like. One or more DL sTTI transmissions in a sTTI time window can also have different starting DL symbol numbers or indices. For example, a first DL sTTI transmission can start at DL symbol #2 and a second DL sTTI transmission can start at DL symbol #4. One or more DL sTTI transmissions in a sTTI time window can be indexed in an increasing order.

[0177] A sPUCCH resource set can be configured, reserved, used, determined, or indicated to be associated with a DL sTTI. When a sPUCCH region is associated with Ndstti downlink sTTI resources, Ndstti sPUCCH resource sets can be configured, used, or determined within the sPUCCH region and can be determined based on a downlink sTTI time location, a starting OFDM symbol, or a DL sTTI number, and the like. The Nstti sPUCCH resource sets can not overlap, fully overlap, or partially overlap, and the like, within the sPUCCH region.

[0178] In one embodiment, a WTRU can receive one or more DL sTTI transmissions associated with a sPUCCH region and can transmit a sPUCCH resource as a HARQ-ACK transmission or report. The sPUCCH resource can contain one or more HARQ-ACKs associated with one or more DL sTTI transmissions. When a WTRU receives more than one DL sTTI transmission that can be associated with a sPUCCH region, a single sPUCCH resource can be transmitted. For this configuration, a single sPUCCH resource can be used to send a bundled HARQ-ACK transmission or report. For example, if at least one of the one or more DL sTTI transmissions has an error, the WTRU can send a negative HARQ-ACK or NACK for the one or more DL sTTI transmissions. An error can occur when a WTRU fails to receive at least one of the DL sTTI transmissions. If all of the configured DL sTTI transmissions are received without error, the WTRU can send a positive HARQ-ACK or ACK.

[0179] A first sPUCCH resource is used for a bundled HARQ-ACK transmission or report that can be associated with a first DL sTTI transmission of one or more DL sTTI transmissions for a WTRU. A single sPUCCH resource can be selected, determined, or used within a sPUCCH resource set to indicate one or more HARQ-ACK transmissions or reports. The selection of a sPUCCH resource can indicate HARQ-ACK information. For example, if a WTRU selects or uses a first sPUCCH resource, the selection can indicate a negative HARQ-ACK for a second DL sTTI transmission. If a WTRU selects or uses a second sPUCCH resource, the selection can indicate a positive HARQ-ACK for a second DL sTTI transmission. In addition, for the examples given here, a modulation scheme constellation or modulation scheme such as BPSK or QPSK can be used to indicate a positive / negative HARQ-ACK.

[0180] Table 6 shows an example of HARQ-ACK transmission or reporting using sPUCCH resource selection and QPSK modulation when sPDSCH is scheduled for the WTRU in one or more sPDSCH resources associated with a sPUCCH region. If a single sPDSCH is scheduled in one or more sPDSCH resources, the sPUCCH resource can be associated with the sPDSCH for HARQ-ACK transmission or reporting. If multiple codewords are transmitted, QPSK constellations such as constellation 0 (00), 1 (01), 2 (10), and 3 (11) can indicate the HARQ-ACK information for two codewords. If a single codeword is used, BPSK can be used or a subset of the QPSK constellation can be used. Table 6

[0181] Tables 7 and 8 show examples of HARQ-ACK transmission or reporting using sPUCCH resource selection and QPSK modulation. The WTRU can indicate the HARQ-ACK for one or more sPDSCH transmissions by selecting or determining a sPUCCH resource set and a QPSK constellation. If multiple sPDSCHs scheduled for the WTRU are associated with a sPUCCH, the WTRU can select a sPUCCH resource within the sPUCCH resource set and a modulation scheme constellation. The combination of the sPUCCH resource set and the modulation scheme constellation selection can indicate the HARQ-ACK information for one or more sPDSCHs received. If the WTRU receives one or more sPDSCHs associated with a sPUCCH region, the HARQ-ACK (k) can be transmitted, where k can be determined based on ACK, NACK, or DTX for the one or more sPDSCHs received. In Table 8, NACK is used interchangeably with discontinuous transmission (DTX) and NACK / DTX. Table 7

[0182] In one embodiment, one or more HARQ-ACK(k) association rules or types can be used to support different combinations of sPDSCH scheduling or sPDSCH with normal PDSCH (nPDSCH) scheduling. Table 8 shows an example of Type-1 association rule. Table 9 shows an example of Type 2 association rule. One or more HARQ-ACK(k) association rules can be pre-defined, pre-configured, or determined based on at least one of the following: the number of sPDSCHs associated with a sPUCCH region, the sTTI length or sTTI time window (e.g., sTTI time window size) of sPDSCH and / or sPUCCH. The HARQ-ACK(k) association rule or type for a sTTI time window can be based on an indication from a DCI, a first DCI (e.g., a DCI in or for a sTTI time window, which can be used to schedule or indicate sTTI resources), an indication of a DCI that can be used to schedule one or more sPDSCHs, a number of sPDSCHs scheduled in a sTTI time window, a higher layer configuration or a number of sTTI time windows, and the like. The HARQ-ACK(k) association rule or type for a sTTI time window can also be determined based on a subframe number, a larger time window such as a radio frame, a SFN number, a super SFN number, or a pre-defined or known signal, which can be used as a sTTI resource indicator, which can be used to indicate the presence of sTTI resources within a sTTI time window, for example. Table 8 Table 9 sPDSCH#1 sPDSCH#2 sPDSCH#3 sPDSCH#4 HARQ-ACK(1) ACK - - - HARQ-ACK(2) NACK - - - HARQ-ACK(3) ACK ACK - - HARQ-ACK(4) ACK NACK - - HARQ-ACK(5) - ACK - - HARQ-ACK(6) - NACK - - HARQ-ACK(7) NACK ACK - - HARQ-ACK(8) NACK NACK - - HARQ-ACK(9) - - ACK - HARQ-ACK(10) - - NACK - HARQ-ACK(11) - - ACK ACK HARQ-ACK(12) - - ACK NACK HARQ-ACK(13) - - - ACK HARQ-ACK(14) - - - NACK HARQ-ACK(15) - - NACK ACK HARQ-ACK(16) - - NACK NACK

[0183] When a WTRU is scheduled for multiple sPDSCHs (e.g., 4 sPDSCHs) in a sTTI time window, a first HARQ-ACK(k) Type 1 association rule can be used. When one or more WTRUs are scheduled for one or more sPDSCHs in a sTTI time window, a second HARQ-ACK(k) Type 2 association rule can be used. The HARQ-ACK(k) association rule of Type 1 can allow for N1 sPDSCHs to be scheduled for a WTRU within a sTTI time window, and the HARQ-ACK(k) association rule of Type 2 can allow for N2 sPDSCHs to be scheduled for a WTRU. N1 and N2 can be different.

[0184] In an embodiment, the WTRU can perform sPUCCH resource selection for HARQ-ACK transmission or reporting based on the number of sPDSCH transmissions within a sTTI time window or the number of sPDSCH associated with a sPUCCH region. The sTTI time window can be determined based on the number of sPDSCH associated with a sPUCCH region or the sTTI length of each sPDSCH. For example, if the sPDSCH length is Nstti symbols and Nsp sPDSCH are associated with the same sPUCCH, the sTTI time window can be Nstti x Nsp [symbols]. The sTTI time window can also be a predefined parameter, a configured parameter or a subframe subframe. If a single sPDSCH is received or scheduled in the sTTI time window, the WTRU can use the sPUCCH resource corresponding to the sPDSCH for HARQ-ACK transmission or reporting. If multiple sPDSCH are received or scheduled in the sTTI time window, the WTRU can determine or select the sPUCCH resource for HARQ-ACK transmission or reporting within the sPUCCH resource set.

[0185] In some examples and embodiments described herein, two transmissions are used with different TTIs, one of which is shorter than the other. These examples and embodiments can be applied to any number of transmissions, TTIs and overlaps. In these embodiments, the shorter TTI can be referred to as a sTTI and the longer TTI can be referred to as an nTTI. The nTTI can be a normal or regular TTI or subframe with a duration of 1 millisecond. The nTTI can be a LTE-A TTI or subframe. A subframe can be a non-limiting example with respect to the nTTI. Other TTIs or time periods can also be used and still be consistent with the examples and embodiments described herein.

[0186] A PDSCH transmission based on or using an nTTI can be referred to as a nPDSCH. A PDSCH transmission based on or using an sTTI can be referred to as a sPDSCH. A PUCCH transmission or PUCCH format transmission based on or using an nTTI can be referred to as a nPUCCH and a PUSCH transmission based on or using an nTTI can be referred to as a nPUSCH. In the examples and embodiments described herein, PDSCH can be used to represent PDSCH, nPDSCH or sPDSCH. In the examples and embodiments described herein, PUSCH can be used to represent PUSCH, nPUSCH or sPUSCH. In the examples and embodiments described herein, PUCCH can be used to represent PUCCH, nPUCCH or sPUCCH.

[0187] If the WTRU can receive a PDSCH in a TTI n, the associated HARQ-ACK for the PDSCH (e.g., nPDSCH or sPDSCH) can be transmitted in TTI n+k, where k can be a positive integer. For example, if the WTRU receives a sPDSCH in TTI n, the WTRU can send the associated HARQ-ACK in TTI n+k. In examples and embodiments described herein, TTI can be replaced by nTTI or sTTI. Further, if the TTI length is the same as the subframe length, TTI can be replaced by subframe.

[0188] A WTRU can receive nPDSCH in a subframe. For example, in addition or in lieu of nPDSCH, the WTRU can receive one or more sPDSCHs in a subframe. If the UL HARQ-ACK timing is different between nPDSCH and sPDSCH, the associated HARQ-ACK for nPDSCH and sPDSCH can need to or can be scheduled to be transmitted from the WTRU in the same uplink subframe, which can be referred to as nTTI and sTTI HARQ-ACK collision.

[0189] FIG. 18 is an example of HARQ-ACK collision occurring between nPUCCH and sPUCCH. The communication 1800 can include nTTI DL 1802, sTTI DL 1816, nTTI UL A / N 1818, and sTTI UL A / N 1820. If the WTRU receives nPDSCH in nTTI n and sPDSCH (1) and sPDSCH (2) in nPTI n+2, and the WTRU can send the HARQ-ACK for these transmissions in the same uplink subframe nTTI n+4 as nPUCCH, sPUCCH (1), or sPUCCH (2), nTTI and sTTI HARQ-ACK collision will occur.

[0190] HARQ-ACK for nPDSCH can be or can be referred to as normal or nTTI HARQ (nHARQ), nACK, nNACK, nHARQ-ACK, nHARQ-NACK, or nACKNACK, among other examples. Here, nHARQ, nACK, nNACK, nHARQ-ACK, nHARQ-NACK, and nACKNACK can be used interchangeably. Further, HARQ-ACK for sPDSCH can be or can be referred to as short or sTTI HARQ (sHARQ), sACK, sNACK, sHARQ-ACK, sHARQ-NACK, or sACKNACK, among other examples. Here, sHARQ, sACK, sNACK, sHARQ-ACK, sHARQ-NACK, and sACKNACK can be used interchangeably. Additionally, HARQ, ACK, NACK, HARQ-ACK, HARQ-NACK, and ACKNACK can be used interchangeably herein.

[0191] In an embodiment, if a WTRU can or can need to transmit nHARQ and sHARQ in a subframe, nHARQ and sHARQ can be multiplexed in a PUCCH transmission. The PUCCH transmission can be at least one of nPUCCH or sPUCCH transmission. As an example, one or more sHARQ can be transmitted with nHARQ by using a single PUCCH transmission or PUCCH format transmission.

[0192] One or more nPUCCH formats can be used herein, a first nPUCCH format can be used if nHARQ is being transmitted, and a second nPUCCH format can be used if nHARQ and sHARQ are multiplexed in a PUCCH transmission. The first nPUCCH format can be or can be configured as PUCCH format la / ib, and the second nPUCCH format can be or can be configured as PUCCH format 2 / 2a / 2b. HARQ-ACK bits for sHARQ can be transmitted in the CQI portion of PUCCH format 2a / 2b, and HARQ-ACK bits for nHARQ can be transmitted in the ACK / NACK portion of PUCCH format 2a / 2b. HARQ-ACK bits for nHARQ and sHARQ can be transmitted in the CQI portion of PUCCH format 2 / 2a / 2b.

[0193] In addition, the first nPUCCH format can be PUCCH format la / lb and the second nPUCCH format can be PUCCH format 3. The first nPUCCH format can be PUCCH format la and the second nPUCCH format can be PUCCH format lb. When PUCCH format lb can be used, one or more bit positions for nHARQ and sHARQ can be predetermined. For example, the first HARQ-ACK bit in the format can be for nHARQ and the second HARQ-ACK bit can be for sHARQ or vice versa. If more than one HARQ-ACK bit for nHARQ or more than one HARQ-ACK bit for sHARQ is to be transmitted or is transmitted, a bundling process can be used. For example, if more than one HARQ-ACK bit for nHARQ can be transmitted, one or more HARQ-ACK bits for nHARQ can be bundled. If more than one HARQ-ACK bit for sHARQ can be transmitted or is to be transmitted, one or more HARQ-ACK bits for sHARQ can be bundled. The nHARQ and sHARQ HARQ-ACK bits can or can not be bundled separately.

[0194] The nPUCCH format can be a PUCCH format, such as a legacy PUCCH format. One or more sPUCCH formats can be used here, where a first sPUCCH format can be used if sHARQ is transmitted, such as only sHARQ is transmitted, and a second sPUCCH format can be used if sHARQ and nHARQ are multiplexed in the sPUCCH transmission.

[0195] The one or more PUCCH types for nHARQ or sHARQ transmission can be nPUCCH types or sPUCCH types. The associated DCI for nPDSCH or sPDSCH can indicate the respective PUCCH type to be used. For example, a WTRU can receive an indication associated with a PUCCH type from a DCI associated with sPDSCH and the WTRU can determine a multiplexing process for nHARQ and sHARQ based on the indication. The PUCCH type can be a PUCCH format and vice versa.

[0196] The PUCCH type can be determined based on the number of HARQ-ACK types that can be transmitted, where the HARQ-ACK types can be nHARQ or sHARQ. For example, a first PUCCH type can be used if a single HARQ-ACK type, e.g., nHARQ or sHARQ, can be transmitted, and a second PUCCH type can be used if more than one HARQ-ACK type, e.g., nHARQ and sHARQ, can be transmitted.

[0197] The WTRU can determine the presence of nPDSCH in an earlier subframe based on the PUCCH type indicated in the DCI. For example, for a subframe in which the WTRU can transmit one or more sHARQs, the WTRU can determine whether an nHARQ is to be transmitted or is to be additionally transmitted based on the PUCCH type indication. The nHARQ can be associated with an nPDSCH that is already present but has not been received or successfully received by the WTRU. Based on the PUCCH type indication, the WTRU can determine the presence of the nPDSCH associated with the nHARQ for the subframe for HARQ transmission. The PUCCH type indication is received by the WTRU together with the DCI, where the DCI is associated with the sPDSCH transmission of the sHARQ to be transmitted. Further, the PUCCH type indication can be replaced by an nPDSCH presence indication. The nPDSCH presence indication can be provided or received in an nTTI, e.g., an nTTI associated with the nHARQ transmission, or an nTTI associated with the sHARQ transmission in the same uplink subframe as the nHARQ transmission for the transmitted nPDSCH. The nTTI associated with the sHARQ transmission can be the nTTI in which the sPDSCH associated with the sHARQ can be received.

[0198] The WTRU can also or can be configured to transmit the nHARQ using a sPUCCH, e.g., in a case where the WTRU can or can need to send the nHARQ and the sHARQ in the same subframe. For example, when the WTRU does not have any uplink transmission (e.g., scheduled or configured uplink transmission) associated with the sTTI, the WTRU can send the nHARQ using a sPUCCH in the sTTI.

[0199] The sPUCCH resources in a subframe can be reserved for nHARQ. The WTRU can determine the sPUCCH resources for nHARQ in a subframe. The sPUCCH resources for nHARQ in a subframe can be determined based on higher layer signaling, dynamic indication from DCI, DCI for sPDSCH, sPUCCH in a first sTTI not scheduled to the WTRU, or sPUCCH in a sTTI reserved for nHARQ, among other examples. For a reserved sTTI, the sTTI can be determined in a WTRU-specific manner. WTRU-specific higher layer signaling can be used to indicate or determine the reserved sTTI. The WTRU can use one or more WTRU-specific parameters to determine the reserved sTTI, such as WTRU-ID. The reserved sTTI can be determined in a cell-specific manner or from cell-specific parameters.

[0200] The WTRU can determine sPUCCH resources in a subframe that can be used to transmit nHARQ. If there are available sPUCCH resources, the WTRU can transmit nHARQ in the sPUCCH resources. If sPUCCH resources are not available, the WTRU can or can be configured to drop one or more nHARQ in a subframe, delay transmission of one or more nHARQ to a later subframe, or simultaneously transmit sPUCCH for sHARQ and nPUCCH for nHARQ, among other examples. If sPUCCH resources are not available, the WTRU can or can be configured to multiplex nHARQ and sHARQ in a PUCCH transmission (e.g., nPUSCH or sPUSCH transmission), or multiplex nHARQ and sHARQ in a PUSCH transmission (e.g., nPUCCH or sPUCCH transmission), among other examples.

[0201] As an example, a set of sTTI resources in a subframe can be restricted or reserved for sPUCCH or sHARQ or sPUCCH carrying sHARQ. For example, a number (e.g., four) of sTTI resources can be defined or configured in a subframe, and a subset of the number of sTTI resources can be configured in the WTRU or used by the WTRU. The configuration can identify or restrict the subset of resources for a particular use, such as sPUCCH or sHARQ or sPUCCH carrying sHARQ. The UE can use the sTTI resources in the subset for sPUCCH or sHARQ or sPUCCH carrying sHARQ. The sTTI resources not in the subset can be used as sPUCCH resources available for nHARQ.

[0202] FIG. 19is an example of nHARQ transmission on sPUCCH. The communication 1900 can include nTTI DL 1902, sTTI DL 1916, nTTI UL A / N 1920, and sTTI UL A / N 1922. In this example, unused sPUCCH resources in sTTI can be used for nHARQ transmission. In the communication 1900, since the WTRU does not have uplink transmission associated with sTTI, the sPUCCH resources in the second sTTI located in nTTI n+4 or sTTI s+5 can be used for nHARQ transmission. The unused sPUCCH resources can be referred to as sPUCCH resources in sTTI even if the WTRU is not scheduled for uplink transmission. The unused sPUCCH resources can be sPUCCH resources that can be used for nHARQ, and vice versa.

[0203] In one embodiment, one or more sPUCCH resources in sTTI can be used for transmitting nHARQ and sHARQ. For example, Ncs sPUCCH resources in sTTI can be reserved for the WTRU, and one of the reserved sPUCCH resources can be selected or determined based on HARQ-ACK information (e.g., ACK or NACK) for nHARQ.

[0204] A set of sPUCCH resources can be reserved, determined, configured, or used based on sPDSCH transmission associated sPUCCH resources. For example, a first sPUCCH resource in the set can be determined based on one or more parameters of sPDSCH transmission, and the remaining sPUCCH resources in the set can be determined in terms of the first sPUCCH resource index. The consecutive Ncs sPUCCH resource indices starting from the first sPUCCH resource index can be used for the set. The sPDSCH transmission parameters that can determine the set of sPUCCH resources can include the starting CCE index of the DCI associated with sPDSCH transmission, the starting PRB index of sPDSCH transmission, the starting symbol index of sPDSCH transmission, the number of allocated PRBs, the MCS level, or the transport block size, etc.

[0205] The set of sPUCCH resources can be reserved, determined, configured, or used based on higher layer configuration or dynamic indication from DCI.

[0206] In examples and embodiments, nHARQ and sHARQ can be switched or replaced with each other. In examples and embodiments, sPUCCH and nPUCCH can be switched or replaced with each other.

[0207] For nHARQ transmission of 1 bit, two sPUCCH resources can be reserved, allocated, or used in a sTTI, where one of the two sPUCCH resources can be selected or determined by a WTRU based on nHARQ HARQ-ACK information. For example, a first sPUCCH resource can be selected to indicate nHARQ ACK, and a second sPUCCH resource can be selected to indicate nHARQ NACK. The selected sPUCCH resource can be used for sHARQ transmission. Alternatively, a sPUCCH resource can be selected or determined based on sHARQ HARQ-ACK information, and the selected or determined sPUCCH resource can be used for nHARQ transmission. The HARQ-ACK information can be ACK or NACK.

[0208] One or more nPUCCH resources can be used in nTTI for nHARQ and sHARQ transmission. Ncs nPUCCH resources can be reserved or allocated in nTTI, and one of the Ncs nPUCCH resources can be selected or determined based on sHARQ HARQ-ACK information. The selected nPUCCH resource can be used for nHARQ transmission.

[0209] When a WTRU is scheduled to transmit nPUCCH and sPUCCH in a sTTI, the WTRU can drop nPUCCH or sPUCCH transmission in the sTTI if the frequency resources of nPUCCH and sPUCCH fully or partially overlap. For the examples given here, dropping transmission can include not generating the transmission or not transmitting the transmission, reducing the transmission power to zero, or setting the transmission power to zero or substantially zero, etc. Dropping nPUCCH in a sTTI can include dropping one or more nPUCCH symbols that can be located in the sTTI, or dropping nPUCCH in the subframe. When sPUCCH in a sTTI is dropped, no sPUCCH transmission will occur in the sTTI.

[0210] The WTRU can also drop the nPUCCH or sPUCCH in the sTTI regardless or substantially regardless of the frequency resource overlap between the nPUCCH and sPUCCH. The WTRU can drop the nPUCCH or sPUCCH when the frequency resources for the nPUCCH and sPUCCH fully or partially overlap, without considering the available transmission power or energy. The WTRU can drop the nPUCCH or sPUCCH in the sTTI based on the available transmission power or energy or the WTRU maximum transmission power or energy (e.g., in the sTTI or for the sTTI) when the frequency resource(s) for the nPUCCH and sPUCCH do not overlap. The available WTRU transmission power or energy can be determined based on whether the total transmission power for transmitting the nPUCCH and sPUCCH exceeds the maximum WTRU transmission power (e.g., P CMAX or P CMAX ,c). The maximum WTRU transmission power can be the maximum output power configured for the WTRU.

[0211] The dropping of the nPUCCH or sPUCCH in the sTTI can be determined based on predefined priority rules for the nPUCCH and sPUCCH. As an example, the sPUCCH can have a higher priority than the nPUCCH. The WTRU can drop the lower priority channel. The priority rules can also be based on the type of information carried in the nPUCCH or sPUCCH. The nPUCCH carrying HARQ-ACK can have a higher priority than the sPUCCH carrying CSI (e.g., CQI / PMI / RI). The sPUCCH carrying HARQ-ACK can have a higher priority than the nPUCCH carrying HARQ-ACK or CSI. Similar priority rules based on the type of information can be applied for nPDSCH or sPDSCH.

[0212] As an example, a WTRU can concurrently transmit nPUCCH and sPUCCH in a short sTTI, where nPUCCH and sPUCCH can be located in different frequencies. The WTRU can transmit or can determine to concurrently transmit nPUCCH and sPUCCH in a sTTI based on at least one of the following: (i) receiving a higher layer configuration for concurrent nPUCCH / sPUCCH transmission; (ii) a capability of the WTRU to support concurrent nPUCCH / sPUCCH transmission; (iii) a DCI for nPDSCH or sPDSCH or a received DCI indicating concurrent nPUCCH / sPUCCH transmission or indicating concurrent transmission of nPUCCH / sPUCCH; or (iv) the WTRU determining that the total transmission power of nPUCCH and sPUCCH is below a predefined threshold. The predefined threshold can be the maximum output power P CMAX or P CMAX ,c.

[0213] When a WTRU is not configured for concurrent nPUCCH / sPUCCH or when the WTRU does not support concurrent nPUCCH / sPUCCH, the WTRU can drop nPUCCH or sPUCCH in a TTI. When the WTRU does not receive a DCI indicating concurrent nPUCCH / sPUCCH transmission or concurrent transmission of nPUCCH / sPUCCH, the WTRU can drop nPUCCH or sPUCCH in a sTTI.

[0214] When a WTRU determines that the total transmission power or energy of nPUCCH and sPUCCH is above a predefined threshold, the WTRU can drop nPUCCH or sPUCCH in a sTTI. The predefined threshold can be the maximum output power P CMAX or P CMAX ,c. The total transmission power can be determined from the transmission power of nPUCCH (e.g., P nPUCCH ) and the transmission power of sPUCCH (e.g., P sPUCCH ).

[0215] A sTTI can be or can correspond to one or more symbols (e.g., OFDM or SC-FDMA symbols), e.g., corresponding to N symbols, where N can be less than 14. A sTTI can correspond to a slot. In examples and embodiments, a sTTI can be replaced by a nTTI and vice versa.

[0216] A WTRU can transmit one or more physical channels or signals, such as one or more PUSCH, PUCCH, PRACH, or SRS, among other examples. A WTRU can transmit one or more channels using a TTI, such as an nTTI. The one or more channel transmissions can be simultaneous, or at least partially overlapping or concurrent. If a WTRU determines that it will exceed a maximum power during the overlap, the WTRU can scale one or more channel powers prior to transmission to avoid exceeding the maximum power. The determination can be based on the calculated channel powers that are not considered overlapping. The channel scaling process can be based on a priority of the channels, which can be defined or known. For example, a PRACH can have a highest priority, a PUCCH can have a next highest priority, a PUSCH carrying UCI can have a next highest priority, and a PUSCH not carrying UCI can have a next priority.

[0217] When a WTRU is to transmit channels using the same TTI, the WTRU can pre-plan based on one or more transmission parameters (e.g., scheduling parameters) of the channels, and can scale the channels as needed. The scaling of the channels can also or instead be based on a predetermined receiver of the channels. For example, in a dual connectivity scenario, a transmission for an eNodeB can have a minimum guaranteed power, where the power will affect the power allocation and scaling in the channels to be transmitted.

[0218] A WTRU can transmit one or more of a PUSCH, PUCCH, PRACH, or SRS, among other examples. A WTRU can transmit one or more channels using a TTI, such as an nTTI or sTTI. One or more sTTI channel transmissions (e.g., a set of sTTI channel transmissions) can at least partially overlap or substantially overlap with one or more or a set of nTTI channel transmissions.

[0219] The term channel scaling can be used to refer to scaling a power of a channel (e.g., a calculated power).

[0220] A WTRU can transmit one or more channels using a TTI, such as an nTTI, and / or can transmit one or more channels using a TTI, such as an sTTI. One or more sTTI transmissions (e.g., a set of sTTI channel transmissions) can at least partially overlap or be concurrent with one or more nTTI channel transmissions (e.g., a set of nTTI channel transmissions). Channel and channel transmission can be used interchangeably herein. A UE can perform transmissions for one or more eNBs in the UL. The UE can perform transmissions for one or more other UEs in a sidelink.

[0221] FIG. 20is an example of overlapping or concurrent TTIs in a communication 2000 using nTTI and sTTI. For the example given here, an overlapping portion of a channel or resource can refer to a portion of an nTTI channel / resource that overlaps at least one sTTI channel / resource or a portion of an sTTI channel / resource that overlaps at least one nTTI channel / resource. An sTTI can overlap one, at least one, or only one nTTI. An nTTI can overlap at least one sTTI. An nTTI can overlap M or at most M sTTIs. An sTTI can be a UL sTTI or a DL sTTI. An nTTI can be a UL nTTI or a DL nTTI.

[0222] For an nTTI configuration 2002 with nTTI of size 1 subframe, its length can be 14 symbols or 1 ms, and an sTTI configuration 2004 with sTTI 1 of size 1 slot can be 7 symbols or 0.5 ms, where M can be 2. For nTTI that can contain 14 symbols and sTTI configurations 2006 and 2008 with sTTI 2 or sTTI 3, the configurations can consist of 4 or 2 symbols, and M can be 3 or 7, respectively. The timing or overlapping relationship between nTTI and sTTI can be fixed or known. For the communication 2000, the sTTI can be at least partially, substantially completely, or completely overlapped by the nTTI. In another example, the sTTI can overlap or partially overlap multiple nTTIs (e.g., 2 nTTIs). For example, the nTTI can be the exemplified sTTI, and the sTTI can be the exemplified sTTI 2. In the exemplified communication 2000, the second and fifth occurrences of sTTI 2 overlap the two occurrences of sTTI 1.

[0223] The set of nTTI channels and the set of short or sTTI channels available for transmission by a WTRU can be for one or the same eNodeB or for one or more serving cells belonging to the same eNodeB. An eNodeB can include or use a scheduler that can perform scheduling or make scheduling decisions for WTRU transmissions. An eNodeB and a scheduler can be used interchangeably. An eNodeB can schedule sTTI channels or nTTI channels. An eNodeB can know exactly or approximately when the set of sTTI channels and the set of nTTI channels available for transmission by a WTRU will partially overlap or be concurrent. An eNodeB can know this information because it can schedule both sets of channels at the same time.

[0224] The WTRU can determine whether the transmission of the set of sTTI channels overlaps or will overlap with the set of nTTI channels transmitted by the WTRU prior to transmitting the set of sTTI channels. The WTRU can determine whether the transmission of the set of sTTI channels will cause the WTRU to exceed the maximum power or budget if the sTTI channels overlap with the nTTI channels prior to transmitting the set of sTTI channels. The determination can be based on a calculation of the power of the channels, for example, without considering the overlap constraint.

[0225] The WTRU can adjust the power of one or more channels if the WTRU determines that it will exceed the maximum power during the overlap. The adjustment can be based on channel priority. The WTRU can adjust (e.g., lower) the power of low priority channels and can not adjust the power of higher priority channels. The WTRU can transmit the adjusted and / or unadjusted channels.

[0226] The WTRU can determine which channel or channels to adjust, how to adjust the power of the channels, or at what time scale or time increment to adjust the power of the channels, among other examples. The determination can be based on the time relationship between the set of sTTI channels and the potentially overlapping set of nTTI channels (e.g., sTTI / nTTI time relationship) or the overlap time between the set of sTTI channels and the potentially overlapping set of nTTI channels (e.g., sTTI / nTTI time overlap), among other examples.

[0227] The determination can also be based on whether the WTRU has scheduling information for the set of sTTI channels of the potentially overlapping set of nTTI channels prior to transmitting the nTTI channels or prior to the start of the nTTI. For example, the determination can be based on whether the WTRU has scheduling information for the set of sTTI channels of the potentially overlapping set of nTTI channels at least a certain time (e.g., threshold amount of time) prior to transmitting the set of nTTI channels or prior to the start of the nTTI.

[0228] The determination can also be based on the channel modulation type or MCS of the channels that can be overlapped by other channels. For example, the determination can be based on the presence of reference signals (e.g., DM-RS) in the overlapping portion of the channels. For example, the determination can be based on the presence of reference signals (e.g., DM-RS) in the non-overlapping portion of the channels. The determination can also be based on whether the set of sTTI channels that can overlap with the set of nTTI channels are for the same destination, the same serving cell, the same eNodeB, the same base station, the same access point, or the same MAC entity. The determination can also be based on whether the set of sTTI channels that can overlap with the set of nTTI channels are scheduled by the same scheduler, the same serving cell, the same eNodeB, the same base station, the same access point, or the same MAC entity.

[0229] For such configurations, the adjustment process or adjustment with respect to channel power can include scaling (e.g., in time) at least a portion of the channel, or dropping at least a portion of the channel (e.g., in time).

[0230] For some configurations, the WTRU can be aware of the sTTI scheduling information prior to nTTI scheduling. For example, the WTRU can expect to receive scheduling information for a set of sTTI channels that can overlap with a set of nTTI channels prior to the start of the nTTI or at least some time (e.g., a threshold amount of time) or a sufficient time range prior to transmitting the set of nTTI channels. Dropping can be the same as scaling to zero or setting to zero. Adjusting a channel and adjusting channel power can be used interchangeably.

[0231] The term overlapping portion of a channel can refer to a portion of a channel that overlaps (e.g., in time) with another channel. For example, the overlapping portion of a channel can be used to refer to an nTTI portion that overlaps with at least one sTTI channel or an sTTI channel portion that overlaps with at least one nTTI channel. Overlapping portion and overlapped portion can be used interchangeably.

[0232] The power adjustment can be performed when the WTRU has the scheduling information. The WTRU can be aware of the sTTI scheduling information prior to the nTTI. For example, the WTRU can be aware of or can receive scheduling information for a set of sTTI channels that can overlap with a set of nTTI channels prior to transmitting the set of nTTI channels or at least some time (e.g., a threshold amount of time) or a sufficient time range prior to the start of the nTTI.

[0233] For example, if the WTRU is aware of the sTTI scheduling information prior to the nTTI, the WTRU can determine which channel or channels to adjust prior to the nTTI transmission or prior to the nTTI, such as a short or sTTI or nTTI channel. The WTRU can determine which channel or channels to adjust based on channel priority rules, such as based on normal or legacy channel priority rules.

[0234] For a channel determined to be adjusted, as an example, if the WTRU is aware of the scheduling information prior to the nTTI, the WTRU can perform the channel adjustment for the channel for the entire TTI or substantially for the entire TTI (e.g., sTTI or nTTI). For example, the WTRU can adjust the channel for the entire TTI or substantially for the entire TTI (e.g., sTTI or nTTI) if the overlap is at or above a threshold. The threshold can be fixed, defined (e.g., pre-defined), configurable, etc., and can be received from a base station (e.g., eNode-B). For example, the threshold can be 3 or 4 symbols.

[0235] For a determined adjusted sTTI channel, as an example, the WTRU can adjust the channel throughout the sTTI or substantially throughout the sTTI if the WTRU knows the sTTI scheduling information prior to the nTTI and / or always. For a determined adjusted nTTI channel, as an example, the WTRU can adjust the channel throughout the nTTI or substantially throughout the nTTI if the overlap is above a threshold when the WTRU knows the sTTI scheduling information prior to the nTTI.

[0236] For a determined adjusted channel, as an example, the WTRU can adjust (e.g., only) the overlapping portion of the channel at least some of the time.

[0237] For a determined adjusted channel, as an example, the WTRU can adjust (e.g., only) the overlapping portion of the channel if the overlap is below or less than or equal to a certain threshold (e.g., one or two symbols) or between two thresholds (e.g., between one and two symbols). The one or two thresholds can be configurable and can be received from a base station or eNode-B. The WTRU can transmit the adjusted and / or unadjusted channel.

[0238] The WTRU can not know the sTTI scheduling information prior to the nTTI. For example, the WTRU can not know (e.g., can not receive) the scheduling information of a set of sTTI channels that can overlap with a set of nTTI channels prior to transmitting the set of nTTI channels or prior to the start of the nTTI (e.g., at least a certain time before, such as a threshold time, or within a sufficient time before).

[0239] As an example, if the WTRU does not know the sTTI scheduling information in advance prior to the nTTI, the WTRU can determine which channel(s) (e.g., sTTI and / or nTTI channels) to adjust prior to the nTTI transmission or prior to the nTTI. For example, the WTRU can not know or can not receive the scheduling information of a set of sTTI channels that can overlap with a set of nTTI channels prior to transmitting the set of nTTI channels or prior to the start of the nTTI. The WTRU can determine which channel(s) to adjust based on channel priority rules (e.g., normal or legacy channel priority rules) and / or other rules.

[0240] For a determined adjusted nTTI channel, as an example, the WTRU can adjust the overlapping portion of the channel if the WTRU does not know the sTTI scheduling information in advance prior to the nTTI.

[0241] For an sTTI channel to be adjusted, as an example, a WTRU can perform the adjustment over the entire sTTI (e.g., substantially over the entire sTTI) or over the overlapping time between the nTTI and the sTTI channel if sTTI scheduling information is not known prior to the nTTI.

[0242] For an sTTI channel to be adjusted, as an example, a WTRU can perform the adjustment over the entire sTTI (e.g., substantially over the entire sTTI) or over the overlapping time between the nTTI and the sTTI channel if sTTI scheduling information is not known prior to the nTTI.

[0243] For an sTTI channel to be adjusted, as an example, a WTRU can perform the adjustment over the entire sTTI (e.g., substantially over the entire sTTI) or over the overlapping time between the nTTI and the sTTI channel if sTTI scheduling information is not known prior to the nTTI.

[0244] A WTRU can perform short or sTTI channel adjustment over the entire sTTI, substantially over the entire sTTI, or over the overlapping time between the nTTI and the sTTI channel. This can be done if sTTI scheduling information is not known prior to the nTTI. The operation can also be performed if the entire sTTI overlaps with the nTTI by more than a threshold (e.g., a predetermined number of symbols).

[0245] For an sTTI channel to be adjusted (as an example, or scaled), a WTRU can adjust the overlapping portion and not adjust other portions. This can be done if the overlap with the nTTI is less than a threshold (e.g., 1 symbol).

[0246] For channel adjustment for a portion of a channel, a WTRU can adjust the channel over an entire symbol (e.g., in accordance with adjustment processing determined for one or more complete symbols) if the portion to be adjusted includes a portion of a symbol. The WTRU can perform this operation if the partial overlap is greater than a threshold.

[0247] If a channel portion to be adjusted spans a complete symbol and a partial symbol, rules for determining the channel to be adjusted can apply (e.g., only apply) to the complete symbol and / or symbols that overlap by at least a threshold amount. Adjustment for the remaining partial overlap symbols can be in accordance with other rules, or can be up to implementation of the WTRU.

[0248] For channel scaling of a portion of a channel, if the portion to be scaled includes a portion of a symbol, different rules can be applied to determine how to scale the power in the partially overlapping symbol to avoid exceeding the maximum power in the partially overlapping symbol, or this can be left to the implementation of the WTRU (e.g., if the partial overlap is below a certain threshold).

[0249] If the portion of the channel to be scaled spans a full symbol and a partial symbol, the rules for determining the channel, symbol, or full symbol to be scaled can be based on the overlap being at least a certain threshold. In addition, the WTRU can perform channel power or energy scaling in the partially overlapping symbol according to different rules or threshold rules to avoid exceeding the maximum power in the partially overlapping symbol.

[0250] As an example, scaling a portion of a channel can impact the performance of modulation schemes that use constellation amplitude information, such as quadrature amplitude modulation (QAM) or x-QAM, where x can be 16, 64, 256, or another integer. As an example, scaling a portion of a channel can not impact the performance of modulation schemes that do not use constellation amplitude information, such as BPSK or QPSK.

[0251] As an example, a WTRU can determine a channel to be scaled according to the examples herein. The WTRU can determine whether to scale or discard a portion of the channel to be scaled based on the modulation scheme used for the channel, such as based on whether the modulation scheme used for or by the channel uses amplitude. As an example, if the modulation scheme used for transmission of the channel does not use amplitude, such as when the modulation scheme is QPSK or BPSK, the WTRU can determine to discard (or scale) a portion of the channel.

[0252] As an example, a WTRU can determine to scale a portion of a channel at an nTTI / sTTI overlap time. The WTRU can determine whether to scale or discard the portion of the channel based on the modulation scheme used for the channel. As an example, if the modulation scheme used for transmission of the channel uses amplitude, such as when the modulation scheme is QAM or x-QAM, the WTRU can determine to scale (or discard) the portion of the channel. If the modulation scheme used for transmission of the channel does not use amplitude, such as when the modulation scheme is QPSK, the WTRU can determine to discard (or scale) the portion of the channel. The WTRU can scale or discard the portion of the channel according to this determination.

[0253] As an example, a WTRU can transmit a partially scaled channel with an indication that a portion of the channel has been scaled or discarded based on the modulation scheme used.

[0254] The adjustment (e.g., scaling and / or dropping) to a portion (e.g., any portion) of a channel can be applied to a full symbol. If the overlapping portion spans one or more full symbols and some portions of one or more symbols, the WTRU can apply the adjustment process to the entire symbol with possible partial overlap, e.g., if the partial overlap is greater than a certain threshold. If the overlap is less than the threshold, the WTRU can not apply the adjustment process to the symbol.

[0255] The base station (e.g., eNode-B) can be aware of the possibility of adjustment (e.g., due to the power limitation or budget of the WTRU) and can adapt or take into account the adjustment when receiving or decoding the channel transmitted by the WTRU. As an example, since the scheduling performed by the base station is based on nTTI and sTTI transmissions, the base station can be aware of the time location of possible adjustment. The base station can be aware of whether the WTRU performs scaling or dropping based on the modulation used for the transmission. The base station can take these awareness into account when receiving and / or decoding the channel transmitted by the WTRU.

[0256] In determining which channel or channels to adjust, the WTRU can or can also take into account signal priority, e.g., physical layer signal priority. As an example, DM-RS can have priority. In determining which channel or channels to adjust, the WTRU can take into account the priority of DM-RS. DM-RS is used as a non-limiting example. Other single-symbol or multi-symbol signals can also be used and are still consistent with the present disclosure.

[0257] As an example, in the overlapping time with the short or sTTI channel, if the reference signal is not taken into account, then regardless of the relative priority of the nTTI and sTTI channels, the nTTI channel with DM-RS has higher priority than the sTTI channel. By giving high priority to the channel with DM-RS during the overlap, scaling or puncturing the DM-RS can be prevented.

[0258] The WTRU can determine that the maximum power or energy can be exceeded during the overlap between the short or sTTI channel and the nTTI channel. The WTRU can determine that the nTTI channel contains DM-RS during the overlap. The DM-RS can have higher priority than one or more channels (e.g., one or more of PUCCH, PUSCH with UCI, and PRACH). If the sTTI channel that can be overlapped by the nTTI channel is a channel with lower priority than the DM-RS, the WTRU can determine to adjust the sTTI channel. If the sTTI channel that can be overlapped by the nTTI channel is not a channel with lower priority than the DM-RS, the WTRU can determine which channel to adjust based on its regular rules, e.g., based on channel priority and / or guaranteed power (e.g., minimum guaranteed power) rules.

[0259] If the nTTI channel contains multiple DM-RS and at least one DM-RS is not within the overlap time in the nTTI, the presence of the DM-RS in the overlap time can not be considered (e.g., by the WTRU) in determining channel priority or channel adjustment. As an example, the DM-RS in the overlap time can be scaled or punctured in accordance with one or more examples described herein.

[0260] If the nTTI channel contains multiple DM-RS and at least one DM-RS is before the overlap time in the nTTI, the presence of the DM-RS in the overlap time can not be considered (e.g., by the WTRU) in determining channel priority or channel adjustment. As an example, the DM-RS in the overlap time can be scaled or punctured in accordance with one or more examples described herein.

[0261] When the WTRU knows the sTTI scheduling information before the nTTI, the presence of the DM-RS in the overlap time can not be considered (e.g., by the WTRU) in determining channel priority or channel adjustment. For this configuration, the WTRU can scale or be able to scale the nTTI channel over the entire nTTI or substantially the entire nTTI, and the scaling of the DM-RS can be acceptable. As an example, when the WTRU knows the sTTI scheduling information before the nTTI, the WTRU can consider the presence of the DM-RS in the overlap time in determining channel priority or channel adjustment.

[0262] The base station can consider the possibility of scaling and / or puncturing the DM-RS in the overlap time, and can use or only use the DM-RS in the overlap time, e.g., for demodulating the channel.

[0263] The nTTI channel with DM-RS in the overlap time can have a higher priority than the short or sTTI channel. As an example, this higher priority can be assigned regardless of whether the short or sTTI channel contains a DM-RS during the overlap, or as an example, this higher priority can be assigned because the short or sTTI channel can be adjusted over the entire sTTI or substantially the entire sTTI.

[0264] In certain configurations (e.g., sometimes or always), nTTI DM-RS can have higher priority than short or sTTI DM-RS. For example, when a WTRU does not know sTTI scheduling information prior to nTTI, nTTI DM-RS can have higher priority than short or sTTI DM-RS. At an overlapping time with nTTI channel, for example, if nTTI channel does not contain DM-RS at the overlapping time, short or sTTI channel with DM-RS can have higher priority than nTTI channel. For a short or sTTI channel to be adjusted, the WTRU can adjust the entire sTTI or substantially the entire sTTI when the short or sTTI channel contains DM-RS or when the overlapping portion of the channel contains DM-RS.

[0265] A WTRU can or can also consider TTI length priority in determining which channel or channels to adjust. As an example, TTI length priority can be used for channels with the same channel and / or signal priority but different TTI lengths. Short or sTTI channels can have higher priority than nTTI channels, and vice versa. Which TTI length has higher priority can be configurable. The configuration can be on a serving cell basis.

[0266] One or more DM-RS patterns can be defined, configured, and / or used, e.g., by a WTRU. As an example, a base station can provide a configuration to a WTRU, and / or the configuration can be received by a WTRU. The one or more DM-RS patterns can be considered a set of patterns. One pattern in the set can be or can be configured to be a default, regular, or normal pattern. As an example, a pattern can indicate which symbol or symbols a WTRU can transmit DM-RS when transmitting a PUCCH or PDUSCH channel.

[0267] A WTRU can use or modify a DM-RS pattern of a channel (e.g., a short or sTTI channel or a nTTI channel) based on an indication that can be provided. The indication can be provided and / or received in a scheduling grant, a DL control channel (e.g., PDCCH or EPDCCH), or a DCI format, among other examples. The indication can be referred to as a DM-RS indicator. The indication can be provided by a base station. The indication can be received by a WTRU.

[0268] A DM-RS indicator can indicate a DM-RS pattern to use when transmitting (e.g., in the UL). For example, a DM-RS indicator in a DL grant can indicate a pattern to use when transmitting a PUCCH containing ACK / NACK for a DL transmission. A DM-RS indicator in a UL grant can indicate a pattern to use when transmitting a PUSCH scheduled by the UL grant. The WTRU can receive the indication. The WTRU can use the indicated DM-RS pattern to transmit a channel, such as a granted PUSCH or PUCCH associated with the DL grant.

[0269] A DM-RS indicator can indicate whether to include DM-RS (e.g., any DM-RS) in a UL transmission. Based on a received DM-RS indicator, a WTRU can use a DM-RS pattern (e.g., an indicated DM-RS) or not use a DM-RS pattern to transmit a channel. As an example, a DM-RS indicator can indicate to move (e.g., from a default or regular location) or place DM-RS of a first channel (e.g., a short or sTTI channel) so as to align with DM-RS of a second channel (e.g., an nTTI channel) that can overlap the first channel. A WTRU can use or modify a DM-RS pattern of a first channel (e.g., a short or sTTI channel) so that one or more DM-RS align (e.g., in time) with DM-RS in a second channel (e.g., an nTTI channel, such as an overlapping second channel). A WTRU can use or modify DM-RS of a first channel based on a received DM-RS indicator that indicates to use or modify DM-RS of the first channel.

[0270] In one or more examples described herein, a first channel can be a short channel or sTTI channel, and a second channel can be an nTTI channel. Alternatively, a first channel can be an nTTI channel, and a second channel can be a short or sTTI channel, such as when a WTRU learns sTTI scheduling information prior to an nTTI.

[0271] A WTRU can determine that a first channel (e.g., a short or sTTI channel) can overlap with a second channel (e.g., an nTTI channel). A WTRU can use or modify a DM-RS pattern of the first channel so that one or more DM-RS align (e.g., in time) with DM-RS in the second channel. This operation can be performed by a WTRU based on a determination that the first and second channels can overlap. Further, a WTRU can autonomously use or modify a pattern, such as without an explicit indication from a base station. As an example, a WTRU can autonomously use or modify the pattern when overlapping short or sTTI and nTTI channels can be dedicated to a same eNodeB or a same serving cell of a same eNodeB.

[0272] The WTRU can use or modify the DM-RS pattern of the second channel (e.g., nTTI channel) such that one or more DM-RS of the second channel that can overlap with the first channel do not overlap with the second channel. The WTRU can use or modify the DM-RS pattern of the second channel based on an indication received (e.g., from a base station) or autonomously (e.g., without explicit indication). The WTRU can have or can be configured with a DM-RS pattern configured for the second channel or a default DM-RS pattern. The WTRU can move at least one DM-RS of the second channel that can overlap with the first channel to a symbol after the end of the overlap (e.g., the first symbol after the overlap).

[0273] The WTRU can puncture data used in a symbol (e.g., the last symbol) dedicated for DM-RS. The WTRU can change at least one predetermined symbol used for data. For example, if the DM-RS in symbol 5 is moved to symbol 8, the data used in symbols 6, 7, and 8 can be moved to symbols 5, 6, and 7, respectively.

[0274] The transmissions performed by the WTRU can be prioritized. The set of nTTI channels and the set of short or sTTI channels transmitted by the WTRU can be for different base stations (e.g., eNode-Bs) or one or more serving cells belonging to different base stations (e.g., eNode-Bs). A base station can schedule the short or sTTI channels and another base station can schedule the nTTI channels. The base stations can not be aware of when the set of short or sTTI channels and the set of nTTI channels transmitted by the WTRU will overlap.

[0275] The WTRU can determine whether the set of sTTI channels will overlap with the set of nTTI channels and whether the maximum power or energy will be exceeded during the overlap before transmitting the set of sTTI channels. If the WTRU determines that it will exceed the maximum power or energy during the overlap, the WTRU can adjust the power or energy of one or more channels.

[0276] For the embodiments described for the WTRU communicating with one base station, eNode-B, or scheduler, these embodiments can be applied for the WTRU communicating with more than one base station, eNode-B, or scheduler, and vice versa. The application of one scenario or another is for non-limiting purposes.

[0277] For nTTI, as an example, if scheduling information for a short or sTTI channel is unknown prior to an nTTI transmission (e.g., prior to a threshold amount of time before), the WTRU can use a virtual grant or allocation for one or more short or sTTI channels to determine power or energy available for an nTTI channel. The terms grant and allocation can be used interchangeably. A virtual allocation can be an allocated set of one or more parameters configured. The virtual allocation can be configured by higher layer signaling, e.g., from a base station. The parameters can include at least one of: a channel indicator, e.g., an indication for a PUSCH and / or PUCCH channel; and / or scheduling information, e.g., resource allocation information for a PUSCH and / or PUCCH. As an example, a virtual allocation can be determined by a WTRU based on at least one previous transmission (e.g., sTTI transmission) on an sTTI, e.g., an UL sTTI transmission and / or a DL sTTI transmission in a previous nTTI or subframe. As an example, a virtual allocation can be determined by a WTRU based on at least one previous transmission (e.g., one or more sTTI transmissions) on an sTTI, e.g., an sTTI UL transmission and / or a DL transmission in the last N nTTIs. As an example, N can be 1 or 2. N can be configured by higher layers. N can depend on one or more of an sTTI length, a maximum sTTI length, and / or an nTTI length.

[0278] A virtual allocation can be based on scheduling or resource allocation of at least one UL and / or DL channel or transmission, e.g., at least one UL and / or DL channel scheduled, allocated, or transmitted in a previous nTTI or subframe. For example, if a WTRU transmitted a sPUSCH in a previous nTTI (e.g., a previous subframe), the WTRU can use the scheduling information and / or a computed power for the sPUSCH, or a scaled version of a previous PUSCH resource allocation for the sPUSCH, as scheduling information or a computed power for a virtual sPUSCH in a current nTTI. In another example, a WTRU can use a scaled version of a previously computed power for a PUSCH for a virtual sPUSCH. The scaling factor can be configured and / or can depend on a time elapsed since the sPUSCH was transmitted, e.g., in a case where a last sPUSCH was transmitted more than one nTTI ago.

[0279] A WTRU can use a virtual short or sTTI channel and / or a virtual short or sTTI channel power to replace an actual short or sTTI channel and / or channel power, thereby employing a regular manner to determine the power allocation of an nTTI channel. A WTRU can determine the power allocation for an entire nTTI or substantially an entire nTTI. A WTRU can apply the determined power allocation to an nTTI. A WTRU can adjust the power of an nTTI in an nTTI, for example, in a case where a short or sTTI channel is scheduled and / or allocated that is not accounted for (e.g., a short or sTTI channel scheduled after the start of an nTTI transmission). To calculate the power of a channel for a virtual sTTI, a WTRU can use a path loss used for an actual transmission at a previous transmitted channel, or a WTRU can use an updated or current path loss to calculate the power.

[0280] A virtual channel can apply or only apply to one or more channel types. For example, a virtual channel type can apply to one or more of a PUCCH, a PUSCH, and a PUSCH carrying UCI. A WTRU can use DL traffic (e.g., a previous PDSCH scheduling and / or reception) to determine a virtual PUCCH allocation. A WTRU can use UL traffic (e.g., a previous PUCCH allocation or transmission) to determine a virtual PUCCH allocation. A WTRU can use UL traffic (e.g., a previous PUSCH scheduling and / or transmission) to determine a virtual PUSCH allocation.

[0281] A WTRU can use or can determine to use a virtual allocation for sTTIs based on a number of short or sTTI channels, Ncstti, scheduled, allocated, and / or transmitted in a previous M nTTIs. M can be 1, 2, or any number and can be configured by higher layers. If Ncstti exceeds a threshold (e.g., if a WTRU determines that Ncstti exceeds a threshold), a WTRU can use a virtual allocation for one or more short or sTTI channels when determining the power of an nTTI.

[0282] If Ncstti does not exceed a threshold (e.g., if a WTRU determines that Ncstti does not exceed a threshold), a WTRU can not use a virtual allocation for one or more sTTI channels when determining the power of an nTTI. For example, if no short or sTTI channels are scheduled, allocated, and / or transmitted in the last M nTTIs, a WTRU can not use a virtual allocation to determine the power of the nTTIs.

[0283] For example, according to one or more of the embodiments described herein, if a short or sTTI transmission is scheduled or allocated, e.g., a short or sTTI transmission that was not taken into account in the process of determining nTTI power, and it is determined that the maximum power can be exceeded in the sTTI, one or more short or sTTI or nTTI channels or signals can be adjusted or modified to avoid exceeding the maximum power.

[0284] The WTRU can include an indication in the nTTI transmission to indicate, e.g., to the base station, that the channel transmission was modified, e.g., because one or more short or sTTI channels encountered a maximum power condition. The WTRU can include the indication in the last symbol, or in one or more PRBs configured or used for such an indication, etc.

[0285] The WTRU can be configured for and / or can use nTTIs on a first serving cell and sTTIs on a second serving cell. The first and second serving cells can be the same serving cell or different serving cells. For example, the WTRU can use carrier aggregation to aggregate carriers of the first and second serving cells. The first and second serving cells can have or can belong to the same or separate schedulers, MAC entities, base stations, and / or eNode-Bs. Dual connectivity can be applied to the first and second serving cells.

[0286] For a TTI, e.g., an nTTI or sTTI, the WTRU or MAC entity using the PH report procedure of the WTRU or MAC entity can determine whether at least one PHR is triggered, as an example.

[0287] The MAC entity can transmit the PHR when the WTRU determines that the PHR has been triggered, as an example. For example, the WTRU can transmit the PHR on a MAC-CE and / or PUSCH or sPUSCH channel when the WTRU determines that the PHR has been triggered. The WTRU can transmit the PHR on a channel, e.g., a PUSCH or sPUSCH, for which the WTRU has a grant or allocation of resources when the WTRU determines that it has UL resources available for a new transmission, as an example.

[0288] The MAC entity may or may be configured to prioritize (e.g., by signaling) the transmission of a PHR and / or other MAC-CE on one TTI length over the transmission of a PHR and / or other MAC-CE on another TTI length. In one example, a MAC entity that may be configured to have and / or use both nTTI and sTTI may or may only determine whether at least one PHR (e.g., one of nTTI or sTTI) may have been triggered. In another example, if both nTTI resources and sTTI resources are available, a MAC entity that may be configured to have and / or use both nTTI and sTTI may or may only transmit a PHR in an nTTI resource (e.g., PUSCH) or an sTTI resource (e.g., sPUSCH).

[0289] An sTTI (e.g., UL sTTI) may overlap with at least one or only one nTTI (e.g., UL nTTI). An nTTI may overlap with at least one sTTI. An nTTI may overlap with M (e.g., at most M) sTTIs.

[0290] A PHR (e.g., a PHR that may be transmitted in an nTTI) may include a PH for the nTTI and one or more PHs that may correspond to an sTTI that overlaps with the nTTI. A PHR that may be transmitted in an sTTI may include a PH for the sTTI and one or more PHs that may correspond to an nTTI that overlaps with the sTTI.

[0291] As an example, the WTRU may send a PHR to the base station. The PHR may include at least one of the following (e.g., the WTRU may include at least one of the following within the PHR): a PH (nTTIPH) that may correspond to an nTTI (e.g., an nTTI that overlaps with the sTTI for which the PH is reported); a PH (sTTIPH) that may correspond to an sTTI (e.g., an sTTI that overlaps with the nTTI for which the PH is reported); a set of sTTIPHs, e.g., an sTTIPH for one or each sTTI in a set of sTTIs that overlap with the nTTI for which the PH is reported; an indication that an sTTI channel or the effect of an sTTI or sTTI channel may be included in the calculation and / or determination of at least one of the following: power, maximum power that may be reported, and / or a PH that may be reported (e.g., for an nTTI); an indication of an sTTI (e.g., an sTTI for which the PH is reported or included in the PHR), e.g., an indication relating to an sTTI within a set of sTTIs that overlap with the nTTI for which the PH is reported; Pcmax,c corresponding to the nTTI; P corresponding to the sTTI CMAX,c; a virtual / real indicator flag or field (V-flag) for the nTTI PH, which can indicate whether the respective nTTI PH is real or virtual, e.g., indicated based on actual transmission or a reference format; a virtual / real indicator flag or field (V-flag) for the sTTI PH, which can indicate whether the respective sTTI PH is real or virtual, e.g., indicated based on actual transmission or a reference format; a power management flag or field, e.g., a P-flag for one or each PH that can be reported, which can indicate, as an example, whether a power back-off due to power management can be applied in determining the P CMAX,c CMAX,c may be used in calculating and / or determining the PH that can be reported.

[0292] A PH (e.g., sTTI PH and / or nTTI PH) that can be included in a PHR can be real or virtual. As an example, if nTTI and sTTI are supported, a PH determination and / or reporting process can be configured, provided, supported, and / or used. The terms calculating or calculation process and determining or decision, as used herein, can be interchangeable in the disclosed examples and embodiments.

[0293] A PH type can be one or more. As an example, a type 1 PH can be a PH for PUSCH. A type 1 PH can be calculated from or based on PUSCH power. A type 1 PH can not include PUCCH channel power, e.g., it is not calculated from or based on PUCCH channel power. A type 1 PH can include the effect of PUSCH transmission (e.g., scheduling for PUSCH transmission) on the maximum power available for determining the PH. A type 1 PH can not include the effect of PUCCH transmission (e.g., scheduling for PUSCH transmission) on the maximum power available for determining the PH. A type 1 PH can be a real PH if PUSCH can be transmitted in the TTI for which the PH is calculated. A type 1 PH can be a virtual PH if PUSCH cannot be transmitted in the TTI for which the PH is calculated, e.g., a reference format can be used.

[0294] ​In one example, Type 2 can be a PH for PUSCH and / or PUCCH. The Type 2 PH can be computed from or based on a PUSCH power and / or a PUCCH power. For example, if a PUSCH transmission occurs in the TTI for which the PH is computed, the Type 2 PH can be computed from or based on the PUSCH power. As an example, if a PUCCH transmission occurs in the TTI for which the PH is computed, the Type 2 PH can be computed from or based on the PUCCH power. The Type 2 PH can include an impact of a PUSCH transmission and / or a PUCCH transmission that can occur in the TTI for which the PH is computed on a maximum power available for determining the PH.

[0295] If no PUSCH and / or PUCCH is transmitted in the TTI for which the PH is computed, a reference format can be used for the PUSCH and / or PUCCH. If both the PUSCH and the PUCCH can use the reference format, the Type 2 PH can be considered or indicated as virtual.

[0296] A PH type can apply to a TTI type or length or to a channel having a TTI type or length. For example, a Type A PH can be an sTTI PH with respect to an sTTI in which the PH is reported and / or for which the PH is reported. The sTTI PH can be a Type A PH.

[0297] A Type A PH can be a PH for sPUSCH. A Type A PH can be a Type 1 PH if the PUSCH is sPUSCH. A Type B PH can be a PH for nPUSCH. A Type B PH can be a Type 1 PH if the PUSCH can be nPUSCH. A Type C PH can be a PH that can be for at least partially overlapping nPUSCH and / or sPUSCH. A Type C PH can be computed from or based on nPUSCH power and / or sPUSCH power (e.g., power of one or more nPUSCH and sPUSCH that can overlap). For example, a Type C PH can be computed based on nPUSCH power if nPUSCH transmission occurs in a TTI (e.g., nTTI) for which the PH is computed. As an example, a Type C PH can be computed from or based on nPUSCH power if nPUSCH transmission occurs in a TTI (e.g., nTTI) for which the PH is reported. As an example, a Type C PH can be computed from or based on nPUSCH power if nPUSCH transmission would overlap with a sTTI for which the PH is reported. As an example, a Type C PH can be computed based on or from sPUSCH power if sPUSCH transmission occurs in a TTI (e.g., sTTI) for which the PH is reported. As an example, a Type C PH can be computed based on or from sPUSCH power if sPUSCH transmission would overlap with a nTTI for which the PH is reported. As an example, a Type C PH can include an effect of nPUSCH transmission and / or sPUSCH transmission occurring in or overlapping with a TTI for which the PH is computed on a maximum power available for determining the PH.

[0298] A PH of type D can be a PH for nPUSCH and / or nPUCCH. If PUSCH can be nPUSCH and PUCCH can be nPUCCH, then a PH of type D can be a PH of type 2. A PH of type E can be a PH for sPUSCH and / or sPUCCH. If PUSCH can be sPUSCH and PUCCH can be sPUCCH, then a PH of type D can be a PH of type 2. A PH of type F can be a PH for nPUSCH, sPUSCH, nPUCCH and / or sPUCCH. A PH of type F can be calculated from or based on nPUSCH power for one or more of PH types B, C, D as described herein. A PH of type F can be calculated from or based on sPUSCH power for one or more of PH types A, C, E as described herein. A PH of type F can be calculated from or based on nPUCCH power for PH type D as described herein. A PH of type F can be calculated from or based on sPUCCH power for PH type E as described herein. As an example, a PH of type F can include an nPUSCH transmission, a sPUSCH transmission, a nPUCCH transmission and / or a sPUCCH transmission that can occur in or overlap with a TTI for which a PH is calculated for an impact on the maximum power available for determining the PH.

[0299] A sTTI PH can be a PH of at least one of the following types: A, C, E and / or F. A nTTI PH can be a PH of at least one of the following types: B, C, D and / or F. A PHR can include one or more PH types, as an example, one or more of PH types 1, 2, A, B, C, D, E and / or F for a serving cell. A PH can be a real PH or a virtual PH. A real PH can use or be based on actual transmission parameters, such as scheduling information. A virtual PH can use or be based on a reference format, such as reference scheduling information.

[0300] A PH can be a real PH if a channel available for determining the PH can be transmitted in a TTI for which the PH is calculated. As an example, a PH can be a real PH if scheduling information for a channel used to determine the PH is available for PH calculation in a TTI for which the PH is calculated.

[0301] A PH can be a virtual PH if a channel available for determining the PH is not transmitted in a TTI for which the PH is calculated. As an example, a PH can be a virtual PH if scheduling information for a channel used to determine the PH is not available for PH calculation in a TTI for which the PH is calculated.

[0302] For PHR reporting in nTTI: at least one of power, maximum power, and PH can be determined based on nTTI scheduling and available (e.g. worst case available) overlapping sTTI scheduling; and / or PHR can include nTTI PH and sTTI PH for one or more overlapping sTTI.

[0303] The terms scheduling and scheduling information used herein can be used interchangeably. Scheduling information can include at least one of resource grant or allocation which can include a number of RBs and / or frequency locations (e.g. frequency locations of RB sets), TBS or number of coded bits, number of UCI or HARQ feedback bits, and processing parameters (e.g. modulation and coding scheme (MCS)), etc. Scheduling information can be received, decoded, and / or determined prior to transmission. As an example, availability of scheduling information (e.g. sTTI for nTTI) can depend on when scheduling information can be received, decoded, and / or determined prior to transmission (e.g. nTTI transmission).

[0304] Scheduling information can be for a channel, e.g. PUSCH or PUCCH. Scheduling information can depend on type of bits that can be transmitted in a TTI or on a channel, e.g. UCI or data bits. Scheduling information for UL transmission can be determined based on DL transmission. For example, number of HARQ feedback or UCI bits that can be transmitted can be determined based on DCI that can provide DL grant.

[0305] As an example, the process for calculating and / or determining nTTI PH and one or more associated values that can be used in the process of calculating and / or determining PH can use scheduling information for nTTI. The associated values can be at least one of power or maximum power.

[0306] For nTTI of a serving cell (e.g. first serving cell), the WTRU can determine power for a channel (e.g. physical channel of the serving cell), maximum power of the serving cell, and / or PH based on at least scheduled transmission, scheduled transmission parameters (e.g. number of RBs scheduled for transmission for nTTI of the serving cell). The scheduled transmission can be PUSCH transmission or PUCCH transmission. The scheduled transmission can be a transmission that can be implicitly or explicitly granted or allocated resources. As an example, PUCCH or sPUCCH transmission for transmission of HARQ feedback can be considered as a scheduled transmission.

[0307] The maximum power of a serving cell (e.g., a first serving cell) can be impacted by another serving cell (e.g., a second serving cell), which can be an in-band serving cell, e.g., a contiguous in-band serving cell. The WTRU can determine the maximum power based at least on transmissions scheduled for an nTTI (e.g., an in-band serving cell nTTI) of the other serving cell (e.g., a second serving cell), which can overlap, e.g., fully overlap or overlap by at least a certain fixed or configured amount, with an nTTI of the serving cell.

[0308] As an example, the processing for calculating and / or determining the nTTI PH and one or more associated values can use the scheduling information for the overlapping sTTI, when such scheduling information is available. For a serving cell (e.g., a first serving cell nTTI), as an example, if scheduling information for an sTTI is available, the WTRU can determine the channel (e.g., a physical channel of the serving cell) power, the maximum power (e.g., for the serving cell) and / or the PH based on transmissions scheduled for an sTTI of the serving cell (and / or another serving cell, e.g., a second serving cell) that can overlap with the nTTI of the serving cell.

[0309] As an example, scheduling information for an sTTI can be available, or can be considered available, if the WTRU has the scheduling information for the sTTI at least a certain amount of time before the start of the nTTI, and the amount of time is sufficient to use the scheduling information.

[0310] The amount of time can be a number of sTTIs (e.g., UL or DL sTTIs), a number of symbols, and / or a number of time samples. The amount of time can be fixed or configured. The amount of time can be WTRU specific. The amount of time can depend on a timing advance (e.g., an applied timing advance) and / or a receive-transmit (Rx-Tx) time difference, such as for a serving cell. The Rx-Tx time difference can be a time difference between a reception timing and a transmission timing of the WTRU.

[0311] In one example, the WTRU Rx-Tx time difference can be defined as TUE_RX - TUE_TX. As an example, TUE_RX can be a WTRU reception timing of a downlink time unit (e.g., a subframe or radio frame) #i, which can be received from a serving cell and can be defined in time by a first detection path, as an example. TUE_TX can be a WTRU transmission timing of an uplink time unit (e.g., a subframe or radio frame) #i. The reference point for the WTRU Rx-Tx time difference measurement can be the WTRU antenna connector.

[0312] An nTTI can use one sTTI from a set of sTTIs. For an nTTI that can overlap with the set of sTTIs, as an example, the processing for calculating and determining power, maximum power, and / or PH can use at least one or only one set of sTTIs.

[0313] As an example, the calculation and / or determination can arbitrarily use one sTTI from the set of sTTIs, where the sTTI can be at least one of: an sTTI for which scheduling information (e.g., available scheduling information) is available to the WTRU; an sTTI for which the WTRU has the most scheduled RBs; an sTTI that results in the largest maximum power reduction grant (e.g., largest MPR and / or largest additional MPR (A-MPR)) used in a process such as determining maximum power (e.g., P CMAX,c ); or an sTTI that can result in the largest maximum power reduction grant related to the location (e.g., close to or not close to the band edge) of scheduled resources used in a process such as determining maximum power (e.g., P CMAX,c ); and / or an sTTI that can result in the lowest maximum power (e.g., for PH calculation that can be for nTTI PH calculation).

[0314] A WTRU can include in a PHR (e.g., a PHR that can be transmitted in an nTTI) at least one of: a PH for an sTTI or an sTTI in a set of sTTIs that can be used by the WTRU in a process of determining power, maximum power, and / or PH for an nTTI transmission; and / or an indication of an sTTI, where the sTTI can be an sTTI in a set of sTTIs that can be used by the WTRU for determining power, maximum power, and / or PH reported in the PHR.

[0315] Scheduling information availability can depend on at least one of a TTI length, e.g., an sTTI length (e.g., UL and / or DL sTTI length) and an nTTI length (e.g., UL and / or DL nTTI). Scheduling information availability can depend on a time between a TTI in which scheduling or causing transmission and a TTI in which transmission can occur.

[0316] Some scheduling information can not be available for a first TTI (e.g., sTTI) that can overlap with a second TTI (e.g., nTTI).

[0317] In one non-limiting example, a WTRU can be configured with nTTI for a first cell (cell 1) and sTTI for a second cell (cell 2). The sTTI can overlap with one nTTI and the nTTI can overlap with M sTTIs. As an example, within a sufficient time before the start of the nTTI (e.g., within a threshold amount of time), the WTRU can or can only receive scheduling information for N of the M sTTIs in order to be able to use the information to calculate and / or determine power, maximum power, and / or PH, where the calculation and / or determination can be for the nTTI.

[0318] For example, the scheduling information can be received a number of TTIs before the transmission. In one non-limiting example, the number can be 4. Referring to the example of sTTIs 3, 7 sTTIs will overlap with the nTTI. When the scheduling information is received 4 sTTIs before the transmission, the scheduling information for the transmission in the fifth sTTI will be received in the first sTTI. The scheduling information for the fifth sTTI can be received after the start of the nTTI and as an example, the scheduling information can not be provided or available for the calculation and / or determination for the nTTI. In this example, N can be less than or equal to 4. FIG. 20

[0319] The sTTI PH can use sTTI scheduling processing. The processing for calculating and / or determining the sTTI PH and one or more associated values can use the scheduling information for the sTTI. For a serving cell (e.g., a first serving cell) sTTI, the WTRU can determine power (e.g., power for a serving cell channel, such as power for a physical channel), maximum power (e.g., maximum power for a serving cell), and / or PH based on a transmission (e.g., scheduled transmission parameters, such as a number of RBs for the scheduled transmission) scheduled for the serving cell sTTI.

[0320] The WTRU can determine maximum power based on at least a transmission scheduled for another serving cell (e.g., a second serving cell) sTTI (e.g., an in-band serving cell sTTI) that overlaps with the serving cell sTTI, such as fully overlapping or at least overlapping by a fixed or configured amount.

[0321] The sTTI PH can use nTTI scheduling processing. As an example, the processing for calculating and / or determining the sTTI PH and one or more associated values can use scheduling information for an overlapping nTTI if the scheduling information is available. The scheduling information for the nTTI can or can always be available for sTTIs that can be overlapped by the nTTI. ​

[0322] For a serving cell (e.g., first serving cell) sTTI, as an example, if scheduling information for an nTTI is available, the WTRU can determine the power, maximum power, and / or PH for a channel (e.g., a physical channel of the serving cell) based on a transmission scheduled for an nTTI of a serving cell (and / or another serving cell, e.g., second serving cell) that overlaps with the serving cell sTTI. As an example, scheduling information is available or considered available if the WTRU has the scheduling information for the nTTI at least a certain amount of time before the start of the sTTI, where the amount of time is sufficient to use the scheduling information.

[0323] Configuration can be provided, e.g., by a base station. As an example, a WTRU can receive and / or use the configuration. As an example, a WTRU can be configured with and / or can use nTTI and / or sTTI on the same or different serving cells. A WTRU can be and / or can be configured to report PH in or for nTTI, only in nTTI, and / or in or for sTTI. A WTRU can report PH in or for sTTI, e.g., when or only when it is configured to report PH in or for sTTI.

[0324] Some example PH reporting examples are disclosed herein. In one example, a cell 1 nTTI with a trigger overlaps with a cell 2 sTTI.

[0325] In an example of PH reporting, a WTRU can be triggered to perform PHR for a first cell (e.g., first serving cell) in or for an nTTI (e.g., the WTRU can determine that PH can be triggered). The WTRU can have a resource granted, allocated, and / or provided for nPUSCH (e.g., for nTTI) on the first cell. The grant or allocation can be for new data. As an example, the WTRU can determine nTTI PH for the first cell.

[0326] As an example, the WTRU can determine whether it has at least one sTTI on a second cell (e.g., second serving cell) that can overlap with the nTTI. As an example, if the WTRU can have (e.g., at the time the WTRU can determine that it can have) at least one overlapping sTTI on the second cell (e.g., second serving cell), the WTRU can determine sTTI PH (e.g., at least one or only one sTTI PH). As an example, the WTRU can determine sTTI PH for the second cell.

[0327] As an example, the WTRU can send, transmit, include, or report the determined nTTI PH and / or the determined sTTI PH on the nPUSCH. As an example, the WTRU can send a MAC-CE on the nPUSCH that can include the nTTI PH and / or the sTTI PH.

[0328] The reported PH can be real or virtual. For example, the reported nTTI PH can be a Type B PH or a Type C PH. As an example, the reported sTTI PH can be a Type A PH or a Type C PH. One or more of Types D, E, and / or F can be determined, reported, and / or used for transmissions that can include control channels (e.g., nPUCCH and / or sPUCCH). The terms send, transmit, and report are used interchangeably in examples and embodiments herein.

[0329] FIG. 21is an example of a PH report 2100. The steps shown can be performed in another order. In the example 2100, at 2102, the WTRU can be triggered for a nTTI or a PHR within the nTTI, e.g., for a first cell (e.g., a first serving cell) (e.g., the WTRU can determine that a PHR can be triggered). At 2104, the WTRU can determine whether it has resources granted, allocated, and / or available for nPUSCH, e.g., on the first cell (e.g., for the nTTI). The WTRU can further determine whether the nPUSCH resources are available for PH transmission or reporting. At 2104, if the WTRU determines that it has nPUSCH resources within or for the nTTI that are available for PH transmission or reporting, at 2106, the WTRU can determine whether there is or it has an overlapping sTTI, e.g., for a second cell (e.g., a second serving cell). At 2106, if the WTRU determines that there is or it has an overlapping sTTI, at 2108, the WTRU can determine at least one overlapping sTTI and at 2110, determine a sTTI PH for at least one determined overlapping sTTI. At 2112, the WTRU can determine a nTTI PH and at 2114, transmit or report the determined PH(s). At 2116, the PH reporting procedure can end and / or restart for the next TTI. If there is no PHR trigger for the nTTI, at 2116, the WTRU can not transmit a PH and the procedure ends, or the WTRU can wait for the next TTI. At 2104, if the WTRU determines that there are no nPUSCH resources within the nTTI that are available for transmitting or reporting a PH within the nTTI, at 2116, the procedure can end or the WTRU can wait for the next TTI. At 2106, if the WTRU determines that there is no overlapping sTTI or it does not have an overlapping sTTI, at 2112, the WTRU can determine a nTTI PH and can continue with steps 2114 and 2116.

[0330] In one example, a triggered cell 1 nTTI overlaps with a cell 2 sTTI. In an example for a PH report, the WTRU can be triggered to perform a PHR in or for a nTTI, e.g., for a first cell (e.g., a first serving cell) (e.g., the WTRU can determine that a PH can be triggered). In the first cell, the WTRU can have resources granted, allocated, and / or available for use for nPUSCH (e.g., for the nTTI). The grant or allocation can be for new data. The WTRU can determine a power for the nPUSCH.

[0331] In a second cell (e.g., a second serving cell), a WTRU can or can not have scheduling information, grant, and / or allocation for a short or sTTI channel (e.g., a channel for sTTI). sPUSCH is used as a non-limiting example of a sTTI channel. Other channels can also be used, such as sPUCCH.

[0332] A sTTI channel (e.g., sPUSCH) can fully or at least partially overlap with nPUSCH. For example, resources (e.g., in time) and / or transmissions for a sTTI channel can overlap with resources (e.g., in time) and / or transmissions for nPUSCH. A sTTI can overlap (e.g., fully or at least partially) with an nTTI (e.g., an nTTI for which a PHR can be triggered). A WTRU can determine a sTTI channel (e.g., sPUSCH) power.

[0333] A WTRU can determine at least one maximum power. For example, a WTRU can determine a maximum power for a first cell and / or a second cell. As an example, if the first and second cells can be the same cell, or if they can be intra-band cells, such as contiguous intra-band cells, a WTRU can determine a maximum power (e.g., P CMAX,c ) for the first cell and the second cell. A WTRU can determine a maximum power (e.g., P CMAX,c 1) for a first cell and a maximum power (e.g., P CMAX,c 2) for a second serving cell. The P CMAX,c 1 and P CMAX,c 2 can be the same. As an example, if the first cell and the second cell can be different cells, and the cells are inter-band and / or non-contiguous (e.g., non-contiguous inter-band) cells, the P CMAX,c 1 and P CMAX,c 2 can be different.

[0334] As an example, a WTRU can determine an nTTI PH (e.g., for nPUSCH) for a first serving cell. As an example, a WTRU can determine a sTTI PH (e.g., for sPUSCH) for a second serving cell.

[0335] An nTTI PH can be P CMAX,c or P CMAX,c 1 minus a determined nPUSCH power. A sTTI PH can be P CMAX,c or P CMAX,c 2 minus a determined sPUSCH power. An nTTI PH or a sTTI PH can be determined based on a nPUSCH power and / or a sPUSCH power.

[0336] As an example, the WTRU can send, transmit, include, or report the determined nTTI PH and / or the determined sTTI PH on the nPUSCH. The WTRU can send a MAC-CE that can include the nTTI PH and / or the sTTI PH, e.g., on the nPUSCH. The WTRU can include the P CMAX,c . The WTRU can include the P CMAX,c 1 and / or P CMAX,c 2 in the PHR.

[0337] As an example, the reported nTTI PH can be a type B PH or a type C PH. As an example, the reported sTTI PH can be a type A PH or a type C PH. One or more of types D, E, and / or F can be determined, reported, and / or used for transmissions that can include control channels, e.g., nPUCCH and / or sPUCCH.

[0338] As an alternative, the WTRU can send, transmit, include, or report the determined nTTI PH and / or the determined sTTI PH, e.g., on the sPUSCH that can overlap with the nPUSCH.

[0339] In one example, a cell 1 nTTI with a trigger can overlap with M cell 2 sTTIs. In another example regarding PH reporting, the WTRU can perform a PHR (e.g., the WTRU can determine to trigger a PH) in or for a nTTI of a first cell, e.g., a first serving cell. In the first cell, the WTRU can have resources granted, allocated, and / or available for use for nPUSCH (e.g., for the nTTI). The grant or allocation can be for new data. The WTRU can determine a power for the nPUSCH.

[0340] As an example, the M sTTIs for a second cell or on a second cell can overlap (e.g., fully or at least partially overlap) with the nTTI for the first cell or on a first cell (e.g., the nTTI for which the PHR can be triggered).

[0341] As an example, in a second cell (e.g., a second serving cell), the WTRU can also have scheduling information, a grant, and / or an allocation for N sTTIs or at least one sTTI channel in each of the N sTTIs. The N sTTIs can be a subset of the M sTTIs that overlap with the nTTI. The N sTTIs can overlap (e.g., fully or at least partially overlap) with the nTTI. One or more (e.g., all) sTTI channels in the N sTTIs can overlap with the nPUSCH.

[0342] The overlap can be full or at least partial overlap. The one or more sTTI channels can be sPUSCH. The one or more of the sTTI channels can be sPUCCH. The WTRU can determine or select at least one of the M sTTIs to use for PH reporting. The WTRU can determine at least one of the N sTTIs to use for PH reporting. The determined sTTI can be the kth sTTI of the M sTTIs.

[0343] For example, the determined sTTI can be at least one of: a sTTI determined in accordance with an implementation of the WTRU; a sTTI for which scheduling information for sPUSCH is available to the WTRU; a sTTI for which scheduling information for sPUCCH is available to the WTRU; a first (e.g., earliest in time) sTTI of the N or M sTTIs for which scheduling information for sPUSCH or sPUCCH is available to the WTRU; a sTTI of the N or M sTTIs having a largest power reduction allowance (e.g., at least one of MPR, A-MPR, P-MPR, or a combination thereof); a sTTI of the N or M sTTIs having a smallest maximum power; and / or a first (e.g., earliest in time) sTTI of the M sTTIs (e.g., without regard to whether the WTRU has scheduling information (e.g., for sPUSCH or sPUCCH) for the sTTI).

[0344] As an example, the WTRU can determine, by selection, at least a sTTI channel (e.g., sPUSCH) of the sTTI channels of the N sTTIs to use for PH reporting. The determined sTTI channel can correspond to the kth sTTI of the M sTTIs.

[0345] As an example, the determined sTTI channel can be at least one of: a sTTI channel determined in accordance with an implementation of the WTRU; a sPUSCH or sPUCCH for which scheduling information is available to the WTRU; a first (e.g., earliest in time) sPUSCH of sPUSCHs for which scheduling information is available to the WTRU; a first (e.g., earliest in time) sPUCCH of sPUCCHs for which scheduling information is available to the WTRU; a sTTI channel of the sTTI channels having a largest power reduction allowance (e.g., at least one of MPR, A-MPR, P-MPR, or a combination thereof); and / or a sTTI channel of the sTTI channels having a smallest maximum power.

[0346] The WTRU can determine a power of the determined sTTI channel. The WTRU can determine a power of the sTTI channel in the determined sTTI. The WTRU can determine at least one maximum power. For example, the WTRU can determine a maximum power of the first cell and / or the second cell. As an example, the WTRU can determine a nTTI PH of nPUSCH. The nTTI PH can be P CMAX,c or P CMAX,c 1 minus the determined nPUSCH power.

[0347] As an example, the WTRU can determine a sTTI PH of the determined or selected sTTI channel. For example, the WTRU can determine a sTTI PH of the determined or selected sTTI based on the power determined for one or more sTTI channels in the determined or selected sTTI.

[0348] The sTTI PH can be P CMAX,c or P CMAX,c 2 minus the at least one determined sTTI channel power.

[0349] As an example, the WTRU can send, transmit, include or report the determined nTTI PH and / or the determined sTTI PH on nPUSCH. For example, the WTRU can send a MAC-CE that can include the nTTI PH and / or the sTTI PH on nPUSCH. The WTRU can include P CMAX,c in the PHR. The WTRU can include P CMAX,c 1 and / or P CMAX,c 2 in the PHR.

[0350] As an alternative, the WTRU can send, transmit, include or report the determined nTTI PH and / or the determined sTTI PH, for example, on sPUSCH that can overlap with nPUSCH.

[0351] The WTRU can include an indication in the PHR that indicates which sTTI or sTTI channel (e.g., sPUSCH and / or sPUCCH) the sTTI PH corresponds to. For example, the WTRU can include an indication that the sTTI PH can correspond to the kth sTTI of M sTTIs that overlap with nTTI. As an example, the WTRU can include a value of k or k-1.

[0352] The number of bits (B) can be used for the indication. The value of B can be fixed or configured. For example, B can be 1, 2, or 3. B can depend on the sTTI length and / or the nTTI length. For example, if the nTTI size is 1 subframe or 14 symbols, B can be 1 for sTTI size of 1 slot or 7 symbols, B can be 1 or 2 for sTTI size of 4 symbols, and / or B can be 2 or 3 for sTTI size of 2 symbols.

[0353] Alternatively, the WTRU can determine the sTTI PH for at least one (e.g., each) sTTI of the M sTTIs that overlap with the nTTI. The determined sTTI PH can be real or virtual. As an example, the WTRU can send, transmit, include, or report the determined nTTI PH and / or the determined sTTI PH (e.g., M sTTI PHs) on the nPUSCH (or sPUSCH that can overlap with the nPUSCH).

[0354] In one example, the sTTI of cell 1 with the trigger overlaps with the nTTI of cell 2. In the example of PH reporting, as an example, the WTRU can perform PHR (e.g., the WTRU can determine that PH can be triggered) in or for the sTTI of the first cell (e.g., the first serving cell) that is triggered. In the first cell, the WTRU can have resources granted, allocated, and / or available for use for sPUSCH (e.g., for sTTI). The grant or allocation can be for new data. The WTRU can determine the power for sPUSCH.

[0355] The WTRU can or can also perform operations using nTTI and / or configured to use nTTI in the second cell. The sTTI can overlap completely or at least partially with the nTTI.

[0356] As an example, the WTRU can determine the sTTI PH for sPUSCH. As an example, the WTRU can determine the nTTI PH for nTTI that can overlap with sTTI.

[0357] As an example, if sPUSCH overlaps with nPUSCH that is granted or allocated resources, the WTRU can determine a real nTTI. As an example, if sPUSCH does not overlap with nPUSCH, the WTRU can determine a virtual nTTI PH.

[0358] As an example, the WTRU can send, transmit, include or report the determined nTTI PH and / or the determined sTTI PH on the sPUSCH. For example, the WTRU can send a MAC-CE on the sPUSCH that can include the nTTI PH and / or the sTTI PH. The WTRU can include one or more maximum powers, e.g., P CMAX,c , P CMAX,c 1 and / or P CMAX,c 2 in the PHR.

[0359] As an alternative, for example, if the PHR trigger is earlier than the start of the nTTI (e.g., sufficiently earlier), the WTRU can send, transmit, include or report the determined nTTI PH and / or the determined sTTI PH on the nPUSCH.

[0360] FIG. 22 FIG. 22 is an example of a sPDCCH region determination process 2200. The WTRU can monitor a short TTI PDCCH (sPDCCH) region (2202). The WTRU can monitor when a downlink sTTI length is configured to be shorter than an uplink sTTI length. The WTRU can determine a sPDCCH region from a set of candidate sPDCCH regions for uplink grant based on a WTRU specific parameter (2204). The WTRU specific parameter can include a WTRU-ID. The WTRU can receive an uplink grant in the determined sPDCCH region (2206). The WTRU can communicate in the network using the uplink grant (2208).

[0361] While combinations of features and elements are described herein, methods embodying various aspects of the present disclosure can include fewer or additional features since not all combinations of features and elements are intended to be limiting. Also, some combinations of features and elements can be utilized independently of the use of other features and elements, and nothing described herein is solely intended to be a separate aspect. Further, the methods described herein can be implemented in a computer program, software, or firmware tangibly embodied in a computer readable medium for execution by, or to control the operation of, a computer or a processor. Examples of computer readable media include a floppy disk, a CD-ROM, a hard disk, a USB drive, a flash drive, a RAM, ROM, PROM, EPROM, EEPROM, or any other suitable memory component. The computer readable medium can be a computer readable storage medium or a computer readable signal medium. A computer readable storage medium can include one or more of a floppy disk, a CD-ROM, a hard disk, a USB drive, a flash drive, a RAM, ROM, PROM, EPROM, EEPROM, or any other suitable memory component. A computer readable signal medium can include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Examples of a computer program or software include a computer program, a piece of code, an instruction, or some combination thereof, for being executed by a computer or a processor.

Claims

1. A wireless transmit / receive unit (WTRU), comprising: processor; as well as transceiver, wherein the processor and the transceiver are configured to receive configuration information indicating a plurality of physical uplink control channel (PUCCH) resources for transmitting uplink control information (UCI) and one or more thresholds associated with a number of hybrid automatic repeat request (HARQ) bits to be included in the UCI, wherein each of the one or more thresholds is associated with one of the plurality of PUCCH resources; wherein each of the plurality of PUCCH resources is associated with a corresponding plurality of PUCCH formats and a corresponding number of orthogonal frequency division multiplexing (OFDM) symbols, wherein the processor and the transceiver are configured to receive a physical downlink control channel (PDCCH) transmission indicating transmission of the UCI, wherein the processor is configured to determine a PUCCH resource from the plurality of PUCCH resources for transmitting the UCI, wherein the determination is based at least on the number of HARQ bits to be included in the UCI and a threshold value associated with the determined PUCCH resource from the one or more threshold values; and The processor and the transceiver are configured to send the UCI using the determined PUCCH resource and a PUCCH format associated with the determined PUCCH resource among the corresponding multiple PUCCH formats.

2. A WTRU according to claim 1, wherein the processor and the transceiver are further configured to receive a short transmission time interval sTTI physical downlink control channel sPDCCH transmission, and wherein the downlink sTTI gap is configured between an sPDCCH region and an uplink sTTI for the PUCCH.

3. The WTRU of claim 1 , wherein: Each of the PUCCH resources is associated with a corresponding number of physical resource blocks (PRBs) or a corresponding number of subcarriers.

4. The WTRU of claim 1 , wherein: The configuration information indicates a starting symbol for at least one PUCCH resource among the multiple PUCCH resources in a time slot.

5. The WTRU of claim 1 , wherein: At least a first PUCCH format of the respective plurality of PUCCH formats is associated with a number of OFDM symbols that is different from a number of OFDM symbols with which at least a second PUCCH format of the respective plurality of PUCCH formats is associated.

6. A method performed by a wireless transmit / receive unit (WTRU), the method comprising: receiving configuration information indicating a plurality of physical uplink control channel (PUCCH) resources for transmitting uplink control information (UCI) and one or more thresholds associated with a number of hybrid automatic repeat request (HARQ) bits to be included in the UCI, wherein each of the one or more thresholds is associated with one of the plurality of PUCCH resources, wherein each of the plurality of PUCCH resources is associated with a respective plurality of PUCCH formats and a respective number of orthogonal frequency division multiplexing (OFDM) symbols; receiving a physical downlink control channel (PDCCH) transmission, the PDCCH transmission indicating transmission of the UCI; determining a PUCCH resource from the plurality of PUCCH resources for transmitting the UCI, wherein the determining is based at least on the number of HARQ bits to be included in the UCI and a threshold value associated with the determined PUCCH resource from the one or more threshold values; and The UCI is transmitted using the determined PUCCH resource and a PUCCH format associated with the determined PUCCH resource among the corresponding plurality of PUCCH formats.

7. The method according to claim 6, further comprising: Receive a short transmission time interval sTTI physical downlink control channel sPDCCH transmission, where the downlink sTTI gap is configured between an sPDCCH region and an uplink sTTI for the PUCCH.

8. The method according to claim 6, wherein: Each of the PUCCH resources is associated with a corresponding number of physical resource blocks (PRBs) or a corresponding number of subcarriers.

9. The method according to claim 6, wherein: The configuration information indicates a starting symbol for at least one PUCCH resource among the multiple PUCCH resources in a time slot.

10. The method according to claim 6, wherein: At least a first PUCCH format of the respective plurality of PUCCH formats is associated with a number of OFDM symbols that is different from a number of OFDM symbols with which at least a second PUCCH format of the respective plurality of PUCCH formats is associated.

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