Wireless transmit receive unit and method implemented thereby

Abstract

Provided herein are methods and systems for operating in a wireless communication system. A first transmission can be initiated with at least a first portion of physical layer resources. A second transmission can be initiated with at least a second portion of the same physical layer resources. The first transmission can be any of a punctured transmission, an interfering transmission, a delay-sensitive transmission, or a short transmission. The second transmission can be an ongoing transmission or a long transmission.

Description

[0001] This application is a continuation of Chinese Patent Application No. 201680058909.X, entitled "System for Enhanced Multiplexing in Wireless Systems," filed September 26, 2016, the contents of which are incorporated herein by reference.

[0002] Cross Reference to Related Applications

[0003] This application claims the benefit of U.S. Provisional Application 62 / 232,022, filed September 24, 2015, and U.S. Provisional Application 62 / 273,969, filed December 31, 2015, the contents of which are incorporated herein by reference. BACKGROUND

[0004] Methods, apparatus, and systems for addressing problems arising in the world of wireless communications have advanced significantly over the years. Mobile communications have progressed through generations of wireless communication technologies to address new usage needs and improve upon old usage patterns in accordance with the needs of the industry. For example, fifth generation (5G) technology attempts to address issues related to improved broadband performance (IBB), industrial control and communications (ICC), vehicle applications (V2X), and massive machine type communications (mMTC). These areas have requirements related to ultra-low transmission latency, ultra-reliable transmission, MTC operation, and multiple spectrum operation modes (SOM). As such, 5G and other generations of wireless communication technology can effectively support data transmissions with different requirements in terms of latency, throughput, and reliability. SUMMARY

[0005] Methods and systems for performing wireless communications can include initiating a first transmission, where the first transmission can be performed using at least a first portion of physical layer resources, and initiating a second transmission, where the second transmission can be performed using at least a second portion of the physical layer resources, where the first portion of the physical layer resources overlaps the second portion of the physical layer resources. Further, methods and systems for signaling transmissions below the MAC layer can include attaching a cyclic redundancy check (CRC) to a data block comprised of a plurality of bits, segmenting one or more source symbols of the plurality of bits, performing a first stage of encoding on the symbols, concatenating the encoded symbols and / or encoded block information attachment, performing a second stage of encoding on one or more code blocks, multiplexing the encoded blocks from the second stage of encoding, performing physical channel processing, and transmitting the signal. BRIEF DESCRIPTION OF DRAWINGS

[0006] A more detailed understanding can be had from the following description, given by way of example in conjunction with the accompanying drawings wherein:

[0007] Figure 1Ais a system diagram of an example communications system that can implement one or more embodiments disclosed;

[0008] Figure 1B is a system diagram of an example wireless access network and an example core network that can be used within the communications system illustrated in Figure 1A is a system diagram of an example wireless transmit / receive unit (WTRU) that can be used within the communications system illustrated in

[0009] Figure 1C is a system diagram of an example wireless access network and an example core network that can be used within the communications system illustrated in Figure 1A

[0010] Figure 2 is a diagram of an example process that can be used within the communications system illustrated in Figure 1A

[0011] Figure 3 shows an example process on a transmitter where all multiplexed code blocks come from a single data block;

[0012] Figure 4 shows an example process on a transmitter where multiplexed code blocks come from multiple data blocks;

[0013] Figure 5 shows an example process on a transmitter where multiplexed code blocks come from multiple data blocks;

[0014] Figure 6 shows an example process on a receiver to perform demultiplexing of code blocks;

[0015] Figure 7A shows an encoding example where HARQ is applicable on a transport block basis; and

[0016] Figure 7B shows an encoding example where HARQ is applicable on a code block basis. DETAILED DESCRIPTION

[0017] Figure 1A is a diagram of an example communications system 100 that can implement one or more embodiments disclosed. The communications system 100 can be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 can enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 100 can employ 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), single-carrier FDMA (SC-FDMA), and the like.

[0018] As​​Figure 1A As shown, the communication system 100 can include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network 106, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though it will be appreciated that the disclosed embodiments can apply to any number of WTRUs, base stations, networks and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d can be any type of device configured to

[0019] The communication system 100 can also include base stations 114a and 114b. Each of the base stations 114a, 114b can be any type of device configured to wirelessly interface with one or more WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the core network 106, the Internet 110, and / or the other networks 112. By way of example, the base stations 114a, 114b can 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, and the like. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b can include any number of interconnected base stations and / or network elements.

[0020] The base station 114a can be part of the RAN 104, which can also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), or relay nodes, among others. The base station 114a and / or the base stations 114b can be configured to transmit and / or receive wireless signals within a particular geographic area, often called a cell (not shown). The cell can further be divided into cell sectors. For example, the cell associated with the base station 114a can be divided into three sectors. Thus, in one embodiment, the base station 114a can include three transceivers, one for each sector of the cell. In another embodiment, the base station 114a can use a multiple-input multiple-output (MIMO) technique and, thus, can use multiple transceivers for each sector of the cell.

[0021] The base stations 114a, 114b can communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which can be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared, ultraviolet, visible light, etc.). The air interface 116 can be established using any suitable radio access technology (RAT).

[0022] 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, 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) and / or High-Speed Uplink Packet Access (HSUPA).

[0023] In another embodiment, the base station 114a and the WTRUs 102a, 102b, 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).

[0024] In another embodiment, the base station 114a and the WTRUs 102a, 102b, 102c can use a radio technology such as 5G Radio Access, which can establish the air interface 116 using New Radio (NR) technology.

[0025] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c can implement radio technologies such as IEEE 802.16 (i.e., 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), GSM EDGE (GERAN), and the like.

[0026] As an example, Figure 1AThe base station 114b in such embodiments 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 access points for local networks, which can also be referred to as "Domestic" or "Home" networks. 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 be directly connected to the Internet 110. Thus, the base station 114b can not be required to access the Internet 110 via the core network 106. Figure 1A 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.

[0027] 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, and / or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 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., and / or perform high-level security functions Figure 1A Notably, however, the RAN 104 and / or the core network 106 can in other embodiments 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 employ the E-UTRA radio technology, the core network 106 can also be in communication with another RAN (not shown) employing a GSM radio technology.

[0028] Core network 106 may also act as a gateway for WTRUs 102a, 102b, 102c, and 102d to access PSTN 108, the Internet 110, and / or other networks 112. PSTN 108 may include a circuit-switched telephone network providing Simple Old-Style Telephone Service (POTS). The Internet 110 may include a global interconnected computer network equipment system using common communication protocols, such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and Internet Protocol (IP) from the TCP / IP Internet Protocol suite. Network 112 may include wired or wireless communication networks owned and / or operated by other service providers. For example, network 112 may include another core network connected to one or more RANs, which may use the same RAT as RAN 104 or a different RAT.

[0029] In communication system 100, some or all of the WTRUs 102a, 102b, 102c, and 102d may include multi-mode capability; in other words, WTRUs 102a, 102b, 102c, and 102d may include multiple transceivers communicating with different wireless networks on different wireless links. For example, Figure 1A The WTRU 102c shown can be configured to communicate with base station 114a using cellular-based radio technology, and with base station 114b using IEEE 802 radio technology.

[0030] Figure 1B This is an example system diagram of WTRU 102. (Example...) Figure 1B As shown, WTRU 102 may include a processor 118, a transceiver 120, a transmit / receive unit 122, a speaker / microphone 124, a numeric keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power supply 134, a global positioning system (GPS) chipset 136, and other peripheral devices 138. It should be understood that, while remaining consistent with the embodiments, WTRU 102 may also include any sub-combination of the foregoing components.

[0031] 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, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 can be coupled Figure 1B The processor 118 and the transceiver 120 are depicted as separate components, however, it will be appreciated that the processor 118 and the transceiver 120 can be integrated in an electronic package or chip.

[0032] The transmit / receive element 122 can be configured to transmit signals to, and 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 and / or receive RF signals. In another embodiment, the transmit / receive element 122 can be an emitter / detector configured to transmit and / 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 and / or receive any combination of wireless signals.

[0033] In addition, although the transmit / receive element 122 is depicted in the Figure 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.

[0034] 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.

[0035] 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, and / 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, and / or the display / touchpad 128. In addition, the processor 118 can access information from, and store information in, any suitable memory, such as the non-removable memory 130 and / 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, and store information in, a memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0036] The processor 118 can receive power from the power source 134, and can be configured to distribute and / 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, and the like.

[0037] 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) and / or determine its location based on

[0038] The processor 118 may be further coupled to other peripheral devices 138, which may include one or more software and / or hardware modules that provide additional features, functions, and / or wired or wireless connectivity. For example, peripheral devices 138 may include an accelerometer, electronic compass, satellite transceiver, digital camera (for photos or videos), Universal Serial Bus (USB) port, vibration device, television transceiver, hands-free headset, Bluetooth. Modules, FM radio units, digital music players, media players, video game console modules, and internet browsers, etc.

[0039] Figure 1C The diagram shows an illustrative RAN 104 and an illustrative core network 106 according to an embodiment. As described above, RAN 104 can communicate with WTRUs 102a, 102b, and 102c over air interface 116 using E-UTRA radio technology. RAN 104 can also communicate with core network 106.

[0040] RAN 104 may include eNodeBs 140a, 140b, and 140c; however, it should be understood that RAN 104 may include any number of eNodeBs while remaining consistent with the embodiments. Each eNodeB 140a, 140b, and 140c may include one or more transceivers communicating with WTRUs 102a, 102b, and 102c on air interface 116. In one embodiment, eNodeBs 140a, 140b, and 140c may implement MIMO technology. Thus, for example, eNodeB 140a may use multiple antennas to transmit and receive radio signals from WTRU 102a.

[0041] Each eNodeB 140a, 140b, and 140c can be associated with a specific cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, uplink and / or downlink user scheduling, etc. For example... Figure 1C As shown, nodes B140a, 140b, and 140c can communicate with each other on the X2 interface.

[0042] Figure 1C The core network 106 shown may include a Mobility Management Entity Gateway (MME) 142, a Serving Gateway 144, and a Packet Data Network (PDN) Gateway 146. While each of the foregoing components is described as part of the core network 106, it should be understood that any of these components may be owned and / or operated by an entity other than the core network operator.

[0043] The MME 142 can be connected to each of the eNode Bs 140a, 140b, 140c in the RAN 104 via an SI interface and can serve as a control node. For example, the MME 142 can be responsible for authenticating users of the WTRUs 102a, 102b, 102c, for activating / deactivating specific bearer configurations, and the like. The MME 142 can also provide a control plane function for switching between the RAN 104 and other RANs (not shown) using other radio technologies, such as GSM or WCDMA.

[0044] The serving gateway 144 can also be connected to the PDN gateway 146, which can provide the WTRUs 102a, 102b, 102c with access to packet- switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0045] The serving gateway 144 can also be connected to the PDN gateway 146, which can provide the WTRUs 102a, 102b, 102c with access to packet- switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0046] The core network 106 can also serve as a gateway for the WTRUs 102a, 102b, 102c to access other networks. For example, the core network 106 can provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional landline

[0047] 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 can contain gateway functionality. Also, the access router 165 can be in communication with a plurality of access points (APs) 170a, 170b. Communication between the access router 165 and the APs 170a, 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 the air interface.

[0048] In Figure 1A the exemplary communications system 100 can be a 5G communications system with flexible radio access. The system 100 can have use cases related to improved broadband performance (IBB), industrial control and communications (ICC), vehicle applications (V2X), and massive machine type communications (mMTC), and its requirements can include, but are not limited to, the following: ultra-low transmission latency, support for ultra-reliable transmissions, support for MTC operation, and multiple spectrum operation modes (SOM).

[0049] In order to support ultra-low transmission latency, if operating with air interface latency as low as 1 millisecond round trip time (RTT), it can be necessary to support transmission time intervals (TTIs) of 100 microseconds or less. Support for ultra-low access latency (e.g., the time from initial system access to completion of the first user plane data unit transmission) can be of interest, but can be of relatively low priority. ICC and V2X can require end-to-end (e2e) latency of less than 10 milliseconds.

[0050] Support for ultra-reliable transmissions can include at least one design consideration: relatively better transmission reliability than can be achieved with legacy LTE systems, including transmission success and service reliability targets of the order of 99.999%. For example, IC and V2X scenarios can require packet loss rates of less than 10 -6 Another consideration is support for mobility at rates ranging from 0-500 km / h.

[0051] Support for MTC operation, including narrowband operation, can also be desired, where the air interface can efficiently support narrowband operation (e.g., less than 200 KHz), extended battery life (e.g., up to 15 years of autonomy), and minimal communication overhead for small or infrequent data transmissions (e.g., access latency between seconds and hours and low data rates of 1-100 kbps).

[0052] In a wireless communication system, multiple spectrum operation modes (SOMs) can also be desirable. A WTRU 102 can be configured to perform transmissions in accordance with one or more SOMs. For example, a SOM can correspond to transmissions that use at least one of the following: a particular TTI duration, a particular initial power level, a particular HARQ processing type, a particular cap on successful HARQ receptions / transmissions, a particular transmission mode, a particular physical channel (e.g., uplink or downlink), a particular waveform type, or a transmission in accordance with a particular RAT (e.g., legacy LTE) or 5G transmission method. A SOM can correspond to a quality of service (QoS) class and / or related aspects, such as maximum / target latency, or maximum / target block error rate (BLER), among other examples. A SOM can correspond to a spectrum region and / or a particular control channel or aspects thereof, including, by way of example, a search space or DCI type, among other examples.

[0053] Figure 2 An example process based on the 5G communication system 200 is shown in which a first transmission 202 can be initiated, where the first transmission 202 can be performed using at least a portion of physical layer (PHY) resources, which can also correspond to at least a portion of PHY resources associated with a second transmission 204. The first transmission 202 can be referred to as a punctured transmission, an interfering transmission, a latency-sensitive transmission, or a short transmission. The second transmission 204 can be referred to as an ongoing transmission or a long transmission.

[0054] In Figure 2 In the example process shown, the first transmission 202 and the second transmission 204 can be initiated and transmitted by the same entity (e.g., WTRU 102a) or different entities (not shown). The entity performing the transmission or transmitter can be part of or associated with a network infrastructure node, a base station, or a WTRU. The first transmission 202 and the second transmission 204 can be communicated over the air interface 116. The first transmission 202 and the second transmission 204 can be received or targeted by the same entity (e.g., base station 114) or different entities (not shown). The entity performing the reception or receiver can be part of or associated with a network infrastructure node, a base station, or a WTRU. By way of example, the first transmission 202 and the second transmission 204 can be downlink transmissions, uplink transmissions (e.g., as part of a cellular system), or direct WTRU-WTRU transmissions (e.g., sidelink transmissions). In a system using hybrid automatic repeat request (HARQ), feedback 206 can be communicated before and / or after the second transmission 204.

[0055] A WTRU 102 can use any of the methods described herein in accordance with any one or more of the following: a SOM (e.g., a set of resources, a carrier, a subcarrier spacing, a symbol duration, a priority associated with certain data, or a TTI duration, etc.) associated with a transmission, a PHY resource associated with a transmission, a control channel, and / or one or more associated characteristics (e.g., an RNTI associated with a transmission and / or a PHY resource, a search space location, or a CCE, etc.), a received downlink control information, a reference and / or demodulation signal associated with the transmission, a higher layer received configuration (e.g., a configured transmission mode), or a configuration associated with a particular HARQ process or one or more processes (including a set of processes).

[0056] Systems and methods are disclosed herein for robust PHY or MAC layer processing. Processing of at least one transport block (TB) on the PHY and / or MAC layer can be improved such that a TB or data block can be successfully received even if the intended signal is replaced or interfered with by another signal on a subset of resources within the TTI.

[0057] The processing can include transmitting the TB or data block using a plurality of encoded information blocks, where error detection processing is supported for each individual encoded block. Figure 7A and 7B Examples are shown with respect to error detection and processing. Bits of a given encoded block can be modulated into a symbol, which can be mapped into resource elements of a subset of time symbols or time intervals. Thus, interference or puncturing caused by another signal can only affect one or a small number of encoded information blocks, such that the TB or data block can be successfully recovered (e.g., without having to retransmit any information in the relevant transmission, or only retransmitting a subset of the information in the relevant retransmission, and / or by transmitting another encoded information block to complete the relevant transmission).

[0058] In some embodiments, the physical or MAC layer processing can include an encoder stage at the transmitter side or a decoder stage at the receiver side based on a code having the property that K source symbols can be recovered with high probability from K or more encoded symbols. Examples of codes that can satisfy this requirement include fountain codes, LT codes, or Raptor codes. Without loss of generality, the encoder stage in the embodiments disclosed herein is referred to as a fountain encoding stage or an outer encoding stage, but the encoding stage can also include other types of encoding.

[0059] The source symbols can include any number of information bits. At the transmitter, they can be generated based on the blocks of bits output by a previous processing stage. For example, the source symbols can include the bits of at least one block obtained from a segmentation stage at the transmitter. The fountain encoded symbol bits output by the fountain encoding stage can in turn be used at the input of a further channel encoding stage, which can be based on any forward error correction (FEC) code, such as a convolutional code, a turbo code, or a low-density parity-check (LDPC) code. This further channel encoding stage can also be referred to as an inner encoding stage.

[0060] By including a fountain encoding or outer encoding stage, the robustness of a transmission (e.g., a first transmission in Figure 2 can be improved. For example, the transmission will be more robust against puncturing events or interfering transmissions (e.g., a second transmission in Figure 2 ). This is because interfering transmissions or puncturing events are of limited duration and can thus impair the ability of the receiver to successfully decode a single or a number of fountain encoded blocks of bits that is less than the total number of blocks of bits transmitted (e.g., as opposed to impairing reception of the entire set of information bits transmitted). This processing can be used in a variety of ways. For example, the transmitter can transmit a few more fountain encoded blocks of bits than are needed for successful decoding, so that the receiver can still decode the TB if some of the fountain encoded blocks fail to be successfully decoded (e.g., because of interference or puncturing). The transmitter can have generated a few more fountain encoded blocks of bits to begin with, or can generate the blocks when it determines that more blocks are needed. In another example, upon determining that not enough fountain encoded blocks of a TB or data block have been successfully received to reconstruct the TB or data block, the receiver can request transmission of at least one additional fountain encoded block of the TB or data block. The at least one additional fountain encoded block can include any fountain encoded block (or blocks) that has not yet been successfully received and that is not the same as a previously transmitted fountain encoded block that failed to be decoded.

[0061] Figure 3 An example process at a transmitter in the communication system 100 is shown. In particular, Figure 3The processing of Figure 2 shows an example where all the multiplexed encoded blocks for signal transmission are from a single data block. At the transmitter side, a cyclic redundancy check (CRC) can be attached 302 to the data block obtained from a higher layer (e.g., a MAC layer) for the purpose of performing error detection on the data block. If the higher layer is a MAC layer and the fountain encoding is performed at the physical layer, the "data block" can consist of a MAC PDU or a TB. Alternatively, the fountain encoding can be performed at the MAC layer and / or in a new MAC sublayer, in which case the "data block" can include a MAC or a new MAC sublayer SDU, and possibly additional control information such as MAC control elements (e.g., a power headroom report (PHR) or a buffer status report (BSR), etc.).

[0062] The output can then be segmented 304 into K t source symbols. Each source symbol can include T b bits, e.g., 612, 672, 1024, 2048, or 4096. In some embodiments, a number of padding bits can be appended to the last symbol to make its bit number T b .

[0063] A first stage encoding for K t source symbols of T b bits each can occur at 306. In one embodiment, the first stage encoding is a fountain encoding that can be applied to the K t symbols to provide K t + L t fountain encoded symbols or encoded symbols, where L t is a non-negative integer. At 308, additional bits (hereinafter referred to as symbol information or code block information) can be attached, e.g., attached or prepended, to each fountain encoded symbol or each code block. Such symbol information can include at least a CRC and can be generated for different purposes, e.g., to identify the fountain encoded symbols of a code block and / or the corresponding data block and for error detection. The size of the code block information can be denoted as N si . Each code block can include G symbols and N si code block information bits. The total number of code blocks is denoted as C, where C can be equal to the smallest integer greater than (K t + L t ) / G at least when fountain encoding is applied. The number of code blocks that collectively contain at least K t fountain encoded symbols is denoted as K, and can correspond to the minimum number of blocks needed to decode the data block. The size of a code block can be equal to G x K t + N siThis can be different for the last code block.

[0064] Alternatively, fountain coding can not be applied on the K source blocks, or can be applied with a code rate of 1. In this case, the segmentation into K code blocks 306 is performed after the CRC attachment 302 on the data block, where K is a non-negative integer. Code block information can be attached at least in the case of K > 1, and can include at least one of the following: an identification of the code block, an identification of the data block, and a CRC. The C - K code blocks can be copied from a subset of the original K code blocks, or all of them, in order to provide redundancy.

[0065] Figure 3 The transmitter operation in the example process of FIG. 3 can also include HARQ processing and FEC (or inner) coding. At 310, a second stage coding or inner coding can be performed using an FEC code (e.g., convolutional, Turbo, or LDPC code). Each of the C code blocks can be further encoded in the second stage coding. If fountain coding (or outer coding) was not applied previously, such coding would not be referred to as "second stage" (or inner) coding. The type of FEC code used can depend on the size of each code block. Rate matching using a certain redundancy version (RV) can be performed on each of the C code blocks. The RV can be determined based on HARQ feedback received by the transmitter. Here, the output of the second stage coding and rate matching of a code block can be referred to as a "coded block."

[0066] In one or more embodiments, HARQ processing is applied on a data block basis. In this case, the same RV can be used for all code blocks, and all C coded blocks can be multiplexed in a designated transmission or TTI at 312. As an example, see Figure 7A The figure shows an example where a TB is successfully recovered because of HARQ performed on a transmission block basis.

[0067] Alternatively, in some embodiments, HARQ processing is applied on a code block basis or a fountain coding symbol basis. In this case, the transmitter can encode only a subset of the C code blocks that have not been successfully received based on HARQ feedback. As an example, see Figure 7BThe figure shows an example where HARQ is applied on a code block basis: when some code blocks are lost and exceed the threshold of L-1, it is necessary to retransmit these code blocks. Alternatively, the transmitter can transmit only the number of code blocks equal or close to the number of code blocks that have not been successfully received based on the HARQ feedback (e.g., feedback indicating the number of lost code blocks related to the HARQ process in question). Then, at 312, the C encoded blocks or a subset thereof can be multiplexed in a TTI, after which further physical layer processing can be performed at 314. In one or more embodiments, encoded blocks resulting from different data blocks and / or rate matching with different redundancy versions can be multiplexed in a TTI. In some embodiments, data blocks can be associated with different SOMs. Additional details of the process of selecting encoded blocks based on feedback will be described herein.

[0068] In some embodiments, some control information can be separately encoded and multiplexed with each encoded block inside the same physical channel at 312. As an example, the control information can include information to support HARQ operation, such as the RV associated with at least one code block, the HARQ process identity, the code block identity, or whether a particular code block contains new information or the RV of a previously transmitted code block (e.g., new data indicator (NDI)). The control information can further include information about one or more source symbols or fountain encoded symbols corresponding to the encoded block. The control information can also include information to support whether soft combining can be applied to the transmission, and if so, whether such processing should be performed for the entire transmission, e.g., similar to legacy behavior, on a data block by data block basis (e.g., in case multiple data blocks can be included in the same transmission containing different transport blocks), or on a code block by code block basis (possibly including further indication about one or more applicable code blocks).

[0069] Alternatively or in combination, the control information can include an indication that the encoded block has been preempted or punctured if the transmitter and / or other components or assemblies determine that the resources to be used for the encoded block transmission have been occupied by another transmission.

[0070] At 314, the physical layer processing can further include at least one of scrambling processing, modulation and layer mapping processing, precoding processing, mapping to resource elements, and waveform generation processing. After or before this, the signal can be transmitted from the transmitter 316.

[0071] Figure 4 An example process is shown where the encoded blocks multiplexed in Figure 3 In contrast to the case in Figure 4In the context of the present disclosure, the code rate applicable to the second stage (or inner) coding can be the same or different between code blocks. For the purposes of the present disclosure, reference to Figure 3 the described processes and numbering applies equally to Figure 4 ; for example, the disclosure relating to 302 should be mutually correlated with 402, and so on. Also, for the purposes of the present disclosure, reference to Figure 3 the described processes and numbering applies equally to Figure 5 .

[0072] Figure 5 An alternative exemplary process is shown that is applicable in the case of multiplexing code blocks from multiple data blocks. In this alternative process, the code blocks selected from multiple data blocks can be multiplexed prior to second stage coding.

[0073] In Figure 4 and Figure 5 , the size of the multiple data blocks can be the same or different, as indicated by data block #n or data block #n+m; in all the examples shown in these two figures, the process is the same up to the selection of the code blocks from each data block (see 412 in Figure 4 and 512 in Figure 5 ).

[0074] Figures 2-5 The processes outlined and illustrated in can be modeled so that all the processes can be performed below the MAC layer, or alternatively, without limiting other implementations of the described principles, some of the processes can be performed at the MAC layer and others below the MAC layer.

[0075] Figure 6 An exemplary process at the receiver side is shown in Figures 3-5 , where the corresponding operations can be performed in reverse order with respect to the transmitter side. First, physical channel processing 602 will be performed, where this processing includes, but is not limited to, demodulation, descrambling, and inverse processing for receiving the transmitted signal from the processes in .

[0076] After demultiplexing, the demodulated data corresponding to each encoded block can be decoded at a second stage decoding 606. The second stage decoding 606 can include obtaining the demodulated data corresponding to each encoded block and inputting it to an FEC channel decoder, which can include the inner decoding and / or HARQ processing described herein. The receiver can determine the HARQ process, code block identity, RV, and / or NDI associated with the demodulated data block. The receiver can also determine that the demodulated data block should not undergo further processing (e.g., determine that the demodulated data block should be discarded (not shown)). This can occur, for example, if the receiver determines that the demodulated data is significantly interfered or if the demodulated data does not carry any information useful to the receiver because of preemption, puncturing, or a mismatch between the received WTRU identity and the receiver's WTRU identity. This determination can be based on the received control information or measurements performed on the resources where the data was demodulated.

[0077] At 608, the demodulated data block can be (soft) combined with previously received data blocks corresponding to the same code block that were not successfully decoded. The receiver can determine this based on the HARQ process applicable to the demodulated data block and / or based on the code block identity applicable to the data block.

[0078] The receiver can determine control information related to a particular demodulated data block or all demodulated data blocks in the TTI. The control information can be obtained from at least one of the following: a physical control channel, demultiplexing of the same physical channel as the encoded block, TTI timing, and / or the location of the demodulated data block within the TTI or block sequence, or the properties of the reference signal used for the demodulated data block. The receiver can determine whether the decoding process for the encoded block was successful based on the CRC included in the symbol information demodulated from the symbols.

[0079] After determining the control information, the receiver operation can use the first stage decoding at 610. In one embodiment, the first stage decoding at 610 includes the fountain decoding or outer decoding described herein. The receiver can obtain information related to the content of the successfully decoded block based on at least one of the following: the symbol information demodulated from the symbols, the timing of the TTI, and / or the location of the decoded block within the TTI or block sequence, the properties of the reference signal used to receive the encoded block, or control information received from a physical control channel or demultiplexed from the same physical channel as the encoded block.

[0080] If fountain encoding is configured to be used (e.g., can be applied at the transmitter), at least K different code blocks generated from the data block or at least K tAfter attempting to decode a subset of the different fountain encoded symbols, the receiver can attempt to decode the data block based on a fountain decoder. If the transmission was not performed using fountain encoding, the receiver can attempt to decode the data block after successfully decoding all K original code blocks. Based on the results of the different decoding processes, the receiver can provide feedback to the transmitter to request retransmission at 612.

[0081] The transmitter or receiver (e.g., WTRU 102) can be configured to determine the number, size, and / or duration (e.g., in terms of transmission time) associated with one or more code blocks or encoded information blocks (described below as blocks). In one embodiment, the WTRU 102 can be further configured to determine, for each block or a set of one or more blocks, a starting bit position of the block within a set of bits used for transmission and / or a start time of the block within a TTI. This processing can be part of a HARQ process. Figure 2

[0082] The parameters associated with a transmission used herein can be understood as any parameters that can be predefined or obtained from physical layer or higher layer signaling, explicitly or implicitly. For example, the parameters can be obtained based on field values received in a downlink control information in a physical control channel or multiplexed in a physical data channel.

[0083] The transmissions discussed herein can carry data from H code blocks. The number H can be a parameter associated with the transmission. The number H can also be defined such that each code block occupies a certain number of resources in time, frequency, or space domain. For example, the number H of code blocks can be set such that each code block occupies a certain number of resource blocks and / or a certain number of time symbols. The H code blocks can be generated from a single data block or multiple data blocks.

[0084] The transmissions discussed herein can support a total number of N cb2,tot ​of encoding bits available. The number of encoding bits available can depend on the number of modulation symbols that can be mapped onto resource elements associated with a transmission and the number of encoding bits that can be mapped onto modulation symbols associated with a user. The number can correspond to a modulation order, and if a multi-user superposition technique is used, the number can correspond to a smaller number. The number of modulation symbols can depend on the number of resource elements and a layer mapping scheme, which includes the number of spatial layers (rank) and whether spatial multiplexing, transmit diversity, or another scheme is used. The number of resource elements can depend on the resource allocation in time and / or frequency and can exclude resource elements used for transmitting other signals or channels. Any one or all of the above can be a parameter associated with a transmission. For example, the WTRU 102 can determine the total number of encoding bits N cb2,tot for a particular transmission based on at least one field received in the downlink control information. As an example, the at least one field can include at least one of a resource block assignment field, a field to indicate a modulation order, a field to indicate whether multi-user superposition is used and / or how to map encoding bits to modulation symbols, a field to indicate the number of layers, and / or a field to indicate a set of time symbols (as an example, including a start and / or end symbol and the location of resource elements for reference signals).

[0085] For at least one code block h, the number of bits supported by the transmission discussed herein after the first encoding stage and before the second encoding stage is N cb1,h . The total number of bits on the H code blocks before the second encoding stage can be referred to as N cb1,tot . In some embodiments (as an example, if the first encoding stage is performed at the MAC layer), the total number of bits before the second encoding stage can correspond to a transport block size (TBS). Alternatively, in some embodiments (as an example, if the first encoding stage is performed at the physical layer), the data block size can correspond to a TBS.

[0086] At least in the case where the second encoding stage is applied independently to each code block (e.g., the same as the processing shown Figure 3 or Figure 4 The N cb2,h encoding bits for code block h are obtained after the second encoding stage 310 and 410, respectively. If appropriate, the N cb2，h total number of encoding bits can correspond to N cb2,tot .

[0087] The code rate R 2,h applied to the second encoding stage for code block h can correspond to N cb1,h and N cb2,hbetween the sets.

[0088] In some embodiments, for at least one set of code blocks having at least one code block, the code rate R 2,h applied to each code block can be determined to be the same over the set. In one embodiment, all code blocks carried in a transmission can be applied a unique code rate R2, regardless of which data blocks they are generated from. In another embodiment, the same code rate R 2,hd can be applied to all code blocks generated from a given data block d. In another embodiment, the same code rate R 2,new can be applied to all code blocks that have not been transmitted in a previous TTI. In another embodiment, the code rate R 2,h can be set individually for each code block, whereby for all code blocks, the number of coded bits N cb1,h is not the same before the second stage, but after the second stage, the number of coded bits N cb2,h will be the same.

[0089] As illustrated in Figure 7B , data from at least one code block created and transmitted in a previous TTI and having N cb1,h bits can be carried by a transmission. Such one or more code blocks can be referred to as one or more retransmission blocks. In some embodiments, after the second encoding stage, the number of coded bits N cb2,h and / or the number of code blocks associated with a retransmission block h is the same as the number of coded bits and / or the number of code blocks associated with said code block in the previous TTI. Alternatively, in some embodiments, the number of coded bits N cb2,h and / or the number of code blocks can be determined based on a different code rate R 2,h than in the previous TTI (as illustrated in the example shown in Figure 7B , where the TTI of Y retransmission blocks is TTIY+H). As an example, the code rate R 2,h can be the code rate applied to all code blocks of the transmission, regardless of whether they are retransmission blocks. Alternatively, the code rate R 2,h can be such that the number of coded bits N cb2,h after the second stage is the same as for other blocks.

[0090] The WTRU 102 can determine the total number of bits N 2,set in a set of code blocks to which the same code rate R cb1,set is applied before the second stage. If there is more than one such set (e.g., there are at least two code blocks to which different code rates R 2,h are applied), then the number of bits N ch1,setmay depend on a fraction of the transmission resources, e.g. in terms of the number of coded bits N cb2 ) used for each set. Such fraction(s) and / or resulting code rate(s) can be one or more parameters associated with the transmission. In some solutions, the fraction(s) and / or code rate(s) can depend on the SOM, QoS and / or bearer type associated with the data block. Such fraction(s) and / or resulting code rate(s) can be determined in terms of the order of the code blocks in the sequence and / or the physical resource sets used for mapping coded bits in the code blocks. This embodiment can be very beneficial if some physical resource sets have a lower or higher probability of being subject to interference and / or collision.

[0091] If one of the sets contains a retransmission block using the same number of coded bits as in the previous TTI, the fraction of the transmission resources available for the other set(s) can be determined based on the difference between the total number of coded bits N cb2,tot used by the retransmission block and the total number of coded bits N cb2,retx used by the transmission: (N cb2,tot - N cb2,retx ) / N cb2,tot . If the number of coded bits is set to be the same for all blocks after the second stage, the fraction of the resources can correspond to 1 / H, where H is the number of code blocks of the transmission.

[0092] The total number of bits N cb1,set for a set of code blocks can be determined before the second encoding stage. The total number of coded bits N cb2,tot may be determined from the same parameters that can be used to determine the total number of coded bits N cb1,set , and additional parameters applicable to the set and indicative of the code rate, e.g. modulation and coding scheme index. For example, the number of bits N cb1,set may be determined in terms of the modulation and coding scheme index, the number of allocated resource blocks, the number of spatial layers, and, where applicable, the fraction of coded bits applicable to the set. The determination can also take into account any control information that will be multiplexed with the code blocks after the second stage. The fraction of coded bits can be used to multiply the number of allocated resource blocks before using this function.

[0093] The total number of bits N cb1,set for each set can be determined first before the second encoding stage, and at least one parameter associated with the total number of coded bits can be derived from this value. For example, the number of time symbols of the transmission can be determined such that the transmission can accommodate N cb1,set . Such embodiments can be very beneficial for transmission schemes allowing flexible transmission timing.

[0094] Generation processes of blocks in the first encoding stage are disclosed herein. In some solutions, at least one of the following quantities can be determined: a data block size (DBS) of a data block d; a total number of fountain encoded blocks (C) generated for the data block d; a minimum number of blocks (K) required to decode the data block d; a number of blocks H generated for the data block d and included in a transmission d ; a number of additional fountain encoded blocks (C-K) for the data block d; a size (N cb1,h ) of each block h generated from the data block d prior to the second encoding stage; a total size N cb1,setd of the set of blocks generated from the data block d prior to the second encoding stage; a transmission power offset applicable to each or all of the encoded blocks generated for the data block d for the transmission; and / or a total number of code blocks H in the transmission.

[0095] At least one of the above quantities can be a parameter associated with the transmission, and the other quantities can be derived based on the relationships described herein.

[0096] Based on the parameters disclosed herein, the data block size DBS can be related to the size N cb1,h of each code block prior to the second encoding. The size N cb1,h of the code block prior to the second encoding can correspond to G x T b + N si bits.

[0097] A number of code blocks from a data block can be included in a transmission, such as the transmissions discussed herein. A number H d of blocks generated for a data block d can be included in a transmission. If code blocks from more than one data block can be included in a transmission, the number can be less than the total number of code blocks H in the transmission. Otherwise, if code blocks from a single data block are included in a transmission, the number H d of blocks can correspond to H.

[0098] In some embodiments, the number H d of blocks generated for a data block and included in a transmission can correspond to the total number of fountain encoded blocks C. The code rate can also be a parameter of the transmission. For example, if multiplexing code blocks from more than one data block is not allowed, and a location is desired that is robust against interference in time or frequency, such a configuration can be used. The code rate R1 of the first encoding stage can be defined as the ratio K / C, or equivalently as K / H d , or as the number of source symbols K t and the total number of encoded symbols K t + L tThe ratio between them. The data block size can be determined from the following: code rate R1 and / or K, C, and the number of bits N required to account for the symbol information in each code block. si and the number of CRC bits N crc Code block size N in the case of cb1,h The size of the data block can also be determined directly by parameters such as the modulation and coding scheme index, the number of allocated resource blocks, the number of spatial layers, and / or the applicable set, the given parameters K, C (and / or R1), and the size N used to determine each code block. cb1,h How it depends on the total size N cb1,setd A portion of the encoded bits (if appropriate) of a rule (e.g., the rule that encoding can have the same size).

[0099] In some embodiments, the number H of blocks generated for the data blocks included in the transmission d This can correspond to the minimum number K of fountain-coded blocks. As an example, such a configuration can typically be used for the first transmission of data blocks.

[0100] In some solutions, the number H generated for the data blocks included in the transmission d This can be less than the minimum number K of fountain-coded blocks. As an example, this configuration is typically used to provide additional blocks for data blocks if the number of successfully received code blocks in the previous transmission is insufficient. This configuration can also be used for data blocks in that transmission if the available resources in the first transmission are insufficient to accommodate the minimum number K of blocks.

[0101] There may be a correlation between the number of blocks, the size of the blocks, and the overall size of the set of blocks. For example, the number of blocks H corresponding to the values ​​of K and / or CK and / or C. d It can be based on the total size N associated with the transmission. cb1,setd and / or the size N of one or more blocks cb1,h To determine this. Similarly, the total size N. cb1,setd It can be based on the number of blocks associated with the transmission and one or more block sizes N. cb1,h To determine. Similarly, the size N of the one or more blocks. cb1,h It can be based on the total size N associated with the transmission. cb1,setd And the number of blocks. Each such value can be determined by a simple division using the smallest possible integer capable of transmitting all bits. In particular, the calculation can be performed on the block size N of all blocks in the transmission. cb1,hThe same at all times. Alternatively, each value can be determined using a table (e.g., by a table lookup process with respect to known values). In one example, if different blocks for the same transmission have different sizes, then a table lookup process can be performed.

[0102] In some solutions, the overall size N cb1,setd may first be obtained based on the transmission parameters disclosed herein d and from which the number of blocks H cb1,h and the size of each block N cb1,min may be derived. The size of each block can be the same, but this can not include the last block. The minimum N cb1,min and / or maximum N cb1,max of the size of each block can be configurable. The target number of blocks H dt may be configurable. The number of blocks H d may be set to be the target number of blocks H dt unless the resulting size of each block N cb1,h is below the minimum N cb1,min or above the maximum N cb1,max , in which case the number of blocks will be set to be a value less than or greater than H dt , respectively, so that the size of each block remains within the permitted range.

[0103] Alternatively, the size of each block can be different. In such embodiments, the WTRU 102 can determine a series of block sizes to be transmitted as a parameter associated with the transmission and can use the corresponding values to determine the size of each block.

[0104] Alternatively, in some solutions, the number of blocks H d and the size of each block N cb1,h may first be determined, where it is possible to determine them as a parameter associated with the transmission, and the number of bits N cb1,set may be determined based on the previous determination.

[0105] In one embodiment, code blocks from multiple data blocks can be allowed in a transmission. If code blocks from multiple data blocks are allowed to be multiplexed within a TTI, the data block size of a first data block transmitted in a TTI at a first time can also depend on the amount of resources used by code blocks corresponding to a second data block generated in an earlier TTI. For example, if 20% of the resources in a TTI are used to transmit code blocks corresponding to a second data block generated in an earlier TTI, it can be necessary to reduce the size of the first data block. Assuming that code blocks are multiplexed in the time domain, this means that the data block size also depends on the duration of the TTI available for transmitting the data block.

[0106] In one example embodiment, the number of blocks, the block size(s), and the code rate can be determined. One or more of the number of blocks, the block size(s), the code rate, and the number of information bits can be determined in accordance with at least one of the following: an indication received in DCI, a configuration from higher layers, a function of the overall size of information bits associated with the transmission, a function of one or more aspects associated with the SOM of the transmission, and / or a target duration of the code blocks.

[0107] As disclosed herein, an indication can be received in DCI. In one example, the WTRU 102 can receive DCI containing an indication relating to one or more such parameters. For example, the indication can include the number of information bits associated with the transmission. Such a size can correspond to a TBS. For example, the indication can include a block size for the transmission. In another example, the indication can include and / or relate to a range of block sizes. In another example, such an indication can include whether or not to use fountain coding, and if so, how to apply the fountain coding (e.g., in terms of the number of additional information bits to be added). And, in a final example, the indication can be an index pointing to a configuration containing one or more of the above parameters.

[0108] In one embodiment, the configuration can be from higher layers, and can relate to at least one of the following: a block size, a range of block sizes, whether or not fountain coding is applicable, and / or a TBS or DBS (e.g., in the case of a semi-persistent allocation or in the case of a fixed size transmission). And, some or all of the relevant information can further be signaled in a dynamic manner, such that it overrides the relevant configuration aspects pertaining to the transmission.

[0109] The number of information bits can be determined in accordance with a function of the overall size of information bits associated with the transmission (e.g., a TBS). In one embodiment, the WTRU 102 can determine the size of each block, and can use an integer K of blocks that minimally fits all of the information bits. Fountain coding can be applied here, such that L additional blocks are also added.

[0110] The number of information bits can be determined as a function of one or more aspects associated with the SOM being transmitted, such as the duration of the applicable TTI, the physical layer resources, the control channel associated with the transmission, or the transmission bandwidth, among others.

[0111] In another example, the target duration and / or bandwidth of the code block can be used. In particular, the size of the code block can be set such that the duration of the physical resources used to transmit the code block corresponds to a certain value. In this case, the size of the code block can depend on the modulation and coding scheme and the amount of resources allocated in the frequency domain.

[0112] The presence of non-zero values for L and / or the non-zero values can indicate that fountain coding is applicable for the transmission. Such a transmission can correspond to a transmission of a TB.

[0113] In one example embodiment, the code blocks in a transmission can be from a single data block. The WTRU 102 can first determine the code rate R1 of the first encoding stage (e.g., the fountain encoding stage of the data block). Such a data block can correspond to a transport block. The code rate can correspond to the ratio between the minimum number of code blocks K and the total number of code blocks C used for the data block, or to the ratio between the number of source symbols K t and the total number of encoded symbols K t + L t In some embodiments, the code rate R1 can be determined from physical layer signaling, higher layer signaling, or a combination thereof. For example, a field received in the downlink control information can indicate one code rate from a set of possible code rates (e.g., {1, 9 / 10, 8 / 10, 7 / 10}) configured by radio resource control (RRC). In some solutions, the minimum number of code blocks K and the total number of code blocks C can be explicitly indicated with at least one field in the downlink control information. In this case, the code rate can be obtained by taking the ratio between K and C. In another embodiment, the total number of code blocks C can be predefined or signaled by higher layers, while K can be indicated from the downlink control information. In this embodiment, the total number of code blocks C used for the data block corresponds to the total number of code blocks H in the transmission.

[0114] The WTRU 102 can then determine the DBS corresponding to the TBS based on at least the code rate Rl and other parameters provided by physical layer and / or higher layer signaling, such as the allocation in frequency domain and / or time domain (e.g., number of resource blocks or number of time symbols), an index indicating the modulation and coding scheme (where the coding scheme can describe the code rate of the second encoding stage), and / or the number of spatial layers used by the data block. The mapping can be derived from a pre-defined table and / or formula. For example, the data block size can be obtained from a table whose inputs include the code rate Rl, the available time and frequency resources (e.g., in terms of number of resource elements or resource blocks), and an indication of the modulation and coding scheme. In another example, the table can take as inputs the adjusted (e.g., multiplied by the code rate Rl) amount of available resources and an indication of the modulation and coding scheme.

[0115] Alternatively, the WTRU 102 can determine the data block size (DBS) directly based on legacy solutions and parameters (e.g., without taking into account the additional code rate parameter Rl). In this case, it is assumed that the network will perform any necessary adjustment with respect to the modulation and coding scheme (MCS) parameter in order to compensate for the presence of the first stage encoding. The WTRU 102 can then use the code rate parameter Rl and / or other parameters to derive the number of code block sizes.

[0116] The WTRU 102 can then determine the number of code blocks C and the code block size N cb1,h of the h-th code block. The number of code blocks can be determined from physical layer signaling, higher layer signaling, or a combination thereof. Alternatively, the number of code blocks can be determined such that the modulation symbols resulting from each code block after encoding, modulation, and subsequent physical channel processing are limited to a certain number of time symbols and / or frequency resources. For example, the code blocks can be configured to occupy two consecutive time symbols and up to 10 resource blocks, while the transmission can be configured to occupy 10 time symbols and 20 resource blocks. In this case, the number of code blocks can be determined to be C = 10. The one or more approximate code block sizes containing the code block size information N cb1,h may then be determined from the DBS, the code rate Rl of the first stage encoding, the attached CRC size N CRC , and the number of code blocks C. More specifically, the approximate code block size N cb1,h may be determined to be N cb1,h = (DBS + N CRC ) / (Rl x C). In the example where C = 10, if the combined size of the data block and the attached CRC is 4896 bits, and the code rate Rl is 9 / 10, then the approximate code block size N cb1,hmay be 544 bits. The exact code block size of each block can be adjusted up or down from this value to fit one of a predefined set of sizes that can be accepted by the input of the second stage encoder. The number of code blocks and / or the code block size can also be regulated by lower and / or upper limits. For example, the code block size can be limited to be above a minimum threshold (e.g., 288 bits) to limit the overhead from the code block information, or to ensure that at least one symbol can be placed, and / or the code block size can be limited to be below a maximum value that can be accepted by the second stage encoder (e.g., 6000 bits). Additionally, the code block size can be limited to be one of a predefined set of values, such that an integer number of fountain encoded symbols and code block information can be placed in each code block. When the code block size is adjusted due to at least one of the disclosed constraints, the number of code blocks can be reset such that the combined size of all code blocks multiplied by the code rate R1matches or approximately matches DBS + N CRC Additionally, one of the code blocks (e.g., the last code block) can be set to a different or smaller size.

[0117] The WTRU 102 can then determine the number of source symbols K cb1,h , the number of fountain encoded symbols K t + L t , the maximum number of symbols per code block G, and / or the symbol size T b based on the code rate R, the code block size N b and / or the DBS. For example, the symbol size T t and the maximum number of symbols per code block G can be determined in a set of predefined combinations. For example, if the code block size is below a first threshold, the symbol size can be set to a first value, e.g., 612 bits, if the code block size is above the first threshold and below a second threshold, the symbol size can be set to a second value, e.g., 1024 bits, and so on. Similar solutions can be used for the maximum number of symbols per code block G. The total number of fountain encoded symbols K t + L ci can be determined from the number of symbols in each code block and the code block information size N cb1,h . For example, if the code block size N ci of C code blocks is equal to 1056, the code rate R is 9 / 10 and N b is equal to 32, then T t and G can be determined to be 612 and 2, respectively. The total number of fountain encoded symbols can be 20, and the number of source symbols K CRC may be 18. In this example, if N t is 24, then the DBS will be equal to 9192 bits.

[0118] A method for multiplexing coded blocks in a TTI is disclosed herein. In one embodiment, a transmitter can multiplex coded blocks resulting from a single data block in the same TTI and spatial layer, or in the same TTI but in multiple spatial layers. The transmitter can also multiplex any control information to be transmitted, if appropriate. For example, the control information can include channel state information or HARQ-ACK information for uplink transmissions, or HARQ-related information (redundancy version) for downlink transmissions.

[0119] In one or more additional embodiments, a transmitter can multiplex coded blocks resulting from multiple data blocks and applicable control information in the same TTI and spatial layer. For example, the transmitter can include at least one coded block resulting from a first data block and at least one coded block from a second data block. The at least one coded block from the first data block can include one or more retransmissions related to a fountain encoded symbol or source block that was not successfully decoded in a previous TTI.

[0120] If multiplexing coded blocks from multiple data blocks is used, the transmitter can include the coded blocks based on a particular order. For example, the order can be based first on the time at which a first HARQ transmission of a data block, fountain encoded symbol, or source symbol occurred, and then can be based on the order of transmission of the fountain encoded symbol or source block that was inside the data block at the time of the initial transmission of the data block.

[0121] In some solutions, multiplexing bits from different coded blocks can be performed in such a way that the information related to the code blocks occupies resources in time and / or frequency and / or space / layer domain after modulation and mapping to physical resources are performed. This design improves the probability that the number of code blocks that will be affected by interference from other transmissions and / or puncturing is minimized, thereby improving the overall probability of successfully decoding the data blocks. For example, by performing the multiplexing, the information related to the code blocks can be made to occupy all subcarriers related to a subset of contiguous time symbols inside the resources allocated for the transmission, but possibly excluding the first and / or last time symbol. This design can be implemented by concatenating the bits from the coded blocks and mapping the modulated symbols in increasing order of subcarrier first, time symbol second. This arrangement can be particularly appropriate if the interference is in time domain rather than in frequency domain.

[0122] In one embodiment, by performing the multiplexing, the information related to the code block can be made to occupy all time symbols related to a subset of contiguous subcarriers within the resource allocated for the transmission (which can not include the first and / or last subcarriers). This design can be implemented by concatenating the bits from the code block and mapping the modulation symbols in increasing order of time symbol first, subcarrier second. This arrangement can be very advantageous if the interference is in the frequency domain but not in the time domain.

[0123] In another embodiment, by performing the multiplexing process, the information related to the code block can be made to occupy a subset of contiguous time symbols and a subset of contiguous subcarriers, whereby the H t code blocks in the time domain will occupy the time allocation and the H f code blocks in the frequency domain will occupy the frequency allocation within the resource allocated for the transmission. This design can be implemented by interleaving the bits from a set of H t contiguous code blocks of H f to consecutively take N f / H sc bits from each of the H f blocks, where N sc is the number of subcarriers in the allocation, and concatenating the outputs from the H t set in increasing order of subcarrier first, time symbol second, where the modulation symbols have been mapped. Alternatively, this design can be implemented by interleaving the bits from a set of H f contiguous code blocks of H t to consecutively take N t / H ts bits from each of the H t blocks, where N ts is the number of time symbols in the allocation, and concatenating the outputs from the H f set in increasing order of time symbol first, subcarrier second, where the modulation symbols have been mapped. This arrangement can be very advantageous if the interference is in both the frequency domain and the time domain. The number of code blocks C can be equal to H f x H t .

[0124] The WTRU 102 can determine the multiplexing method and related parameters, such as H f and / or H tIn some solutions, the method and parameters can be explicitly indicated from physical layer signaling and / or higher layer signaling (e.g., downlink control information) applicable to the transmission. For example, one of a predefined set of parameters for H f and / or H t may be indicated in a field of the downlink control information. In some solutions, the parameters H f and / or H t may be determined in accordance with other parameters of the transmission. For example, the resources occupied by a single code block can have a maximum number J max of time symbols and / or a maximum number K max of subcarriers or resource blocks. In such cases, the parameter Hf or Htmay be set to a minimum value, whereby, given the resource allocation for the transmission, each single code block does not occupy more than K max subcarriers or more than J max time symbols. The parameters J max and K max may be predefined, configured by higher layers, or indicated by physical layer signaling. These parameters can be adjusted in accordance with the characteristics of the detected interfering signals or puncturing signals in order to minimize the probability that such interfering signals affect a large number of code blocks.

[0125] In some solutions, the order of the code blocks and / or the multiplexing method can depend on at least one attribute associated with the code blocks. Likewise, for example, the set of physical resources, time, frequency, or spatial layers used for the code blocks can depend on at least one attribute. In these solutions, the receiver (e.g., WTRU 102) can infer at least one attribute associated with the code blocks based on the order of the code blocks and / or the set of physical resources used by the code blocks.

[0126] At least one attribute associated with a code block can include whether the code block is a retransmission code block or is being transmitted for the first time.

[0127] At least one attribute associated with a code block can also include the order of the code blocks used in the multiplexing process of the last transmission that included the code block for the purpose of retransmitting the code block; as an example, the order can be the same as in the last transmission; in another example, the process can apply to code blocks generated from data blocks associated with a SOM, where the SOM corresponds to a transmission of the ultra-reliable type.

[0128] At least one attribute associated with a code block can also include the set of physical resources used by the code block in the last transmission that included the code block for the purpose of retransmitting the code block; as an example, the set of physical resources can be the same as in the last transmission.

[0129] The at least one attribute associated with a code block can further comprise an identity associated with the code block, such as a code block identity or an identity of a data block from which the code block is generated;

[0130] The at least one attribute associated with a code block can further comprise a redundancy version for use by a second encoding stage of the code block.

[0131] The at least one attribute associated with a code block can further comprise a retransmission sequence number.

[0132] The at least one attribute associated with a code block can further comprise a HARQ process identity.

[0133] The at least one attribute associated with a code block can further comprise a SOM, QoS and / or bearer type associated with a data block.

[0134] The applicability of the at least one disclosed multiplexing method can depend on at least one parameter associated with the transmission. For example, the downlink control information can indicate a set of retransmission code blocks and / or a corresponding order or a set of physical resources.

[0135] A receiver, which can be, but is not limited to, a WTRU or a network device, can report to a transmitter, which can be, but is not limited to, a network device or a WTRU, information related to the success or failure of the decoding of individual code blocks or statistics and / or measurements thereof, in order to support proper parameter adaptation, where the parameters can be, by way of example, the total number of code blocks C, the code rate R of the first encoding stage, the minimum number of code blocks K used to successfully decode a transmitted data block, and / or the maximum number of time symbols J used for a code block max and the maximum number of subcarriers K max .

[0136] Such reporting can be in addition to, and possibly separate from, HARQ reporting. The information can include the following disclosed herein. The following information can be applicable only when a WTRU 102 receives a transmission and can be provided as uplink control information along with HARQ information: the number or fraction of successfully or unsuccessfully decoded code blocks related to a particular data block or a particular transmission (this information can be provided only when physical layer or higher layer signaling indicates to do so and / or only when a data block is successfully decoded or not successfully decoded); an indication that at least F code blocks were not successfully decoded while a data block was successfully decoded; an indication that at least S code blocks were successfully decoded while a data block was not successfully decoded; the minimum / maximum number of missing code blocks required to successfully decode a particular data block; an indication that no code blocks were successfully decoded; and / or an indication (e.g., a flag) as to whether the decoding results (success or failure) for all code blocks are the same.

[0137] In one embodiment, the information can be reported as physical layer signaling, together with or as part of channel state information, and / or at higher layers (e.g. RRC layer). Such information can include event statistics described herein applicable to a single or multiple transmissions of a data block, e.g. the average number or percentage of transmissions satisfying a certain condition. In the same embodiment, the information can also include a recommended set of parameters applicable to the encoding and / or multiplexing processing of code blocks, where the transmitter's choice of them satisfies a certain performance requirement, e.g. 10% BLER, together with other channel state information parameters. These parameters can include at least one of: code rate R of the first encoding stage; total number of code blocks C; minimum number of code blocks K; and / or number of code blocks in the time and / or frequency dimension of the allocation (H t and / or H f ), or equivalent to the number or fraction of time symbols or subcarriers occupied by the symbols originated from each code block.

[0138] In one embodiment, the measurements can be configured by higher layers and can be applicable to a configured reference resource, e.g. a subframe or a set of subframes. The measurements can include variance and / or maximum difference between certain metric values measured on certain parts of the reference resource, where: the metric can include noise or interference level or signal to noise and interference ratio (SINR); a part of the reference resource can be defined as a contiguous subset of J time symbols and / or K subcarriers or resource blocks, where J and K can be provided as part of the measurement configuration; and / or separate measurements can be reported for different partitions of the reference resource divided into parts, e.g. for different sets of J and K. The measurements can also include an indication of whether the SINR or noise or interference level is consistent across the reference resource, e.g. whether the interference is white or colored across the resource, where the evaluation can be based on whether the variance (possibly in dB) across the reference resource part exceeds a pre-defined or configured threshold, where separate indications related to different partitions of the reference resource divided into parts, e.g. for different sets of J and K, can be reported.

[0139] A WTRU 102 can initiate the process of reporting feedback based on a configuration aspect (e.g., periodic reporting). A WTRU can initiate the process of reporting such feedback (e.g., aperiodic reporting) upon receiving downlink control signaling requesting such feedback. A WTRU 102 can initiate the process of reporting such feedback (e.g., threshold-based reporting) upon satisfying a potentially configurable threshold. In one solution, such a threshold can be based on any one of the parameters disclosed herein to be reported. For example, a WTRU 102 can be configured to report HARQ ACK / NACK feedback in terms of the number of missing or unsuccessfully decoded blocks. As an example, the number of missing blocks can represent a threshold associated with a value, where the value can be a configuration aspect of the WTRU 102. As an example, a WTRU 102 can be configured to not report any HARQ feedback unless the number of missing code blocks for a correctly decoded data block Xl is below a value X2. As an example, a WTRU 102 can be configured to report a HARQ NACK feedback when the non-zero number of code blocks for a correctly decoded data block Xl is below a value X2, and a HARQ ACK when Xl is equal to zero. As an example, in an embodiment that can extend the above, a WTRU 102 can be configured to report the minimum number of missing code blocks Xl when the minimum number is below a value X2. As an example, such a process can be beneficial for a transmitter to determine when to adjust the number of code blocks included in a transmission in order to reduce the transmission of unnecessary information.

[0140] Similarly, a WTRU 102 that performs a transmission using code blocks can take similar actions based on receiving HARQ feedback, for example, a WTRU can adjust the number of code blocks in a transmission upon receiving a HARQ NACK feedback and assuming that the number of missing blocks is less than a threshold X2. In one embodiment, such reporting can be configured per SOM and / or per HARQ process and / or for a specific set of HARQ processes (e.g., a set of HARQ processes associated with a specific SOM). In another embodiment, a WTRU 102 can initiate such reporting process if a negative HARQ feedback is generated for a specific HARQ process.

[0141] A receiver can determine that it should generate and transmit HARQ feedback in accordance with a method in which the receiver can generate a positive HARQ acknowledgement (ACK) if the receiver determines that it successfully received at least K blocks associated with an associated process (e.g., a HARQ process and / or a data block). If fountain coding is used, the receiver can generate an ACK if fountain decoding is successful.

[0142] The receiver can determine that it should generate and transmit HARQ feedback in accordance with a method in which the receiver determines that it successfully received a number of blocks associated with a process (e.g., a HARQ process and / or a data block) that is less than K, or that it cannot receive at least k blocks in accordance with a current decoding state, or that it did not successfully receive any blocks, or that the fountain decoding failed when it was applicable, then the receiver can generate a negative HARQ acknowledgement (NACK).

[0143] In an embodiment, the receiver generates feedback only if it determines that HARQ processing (e.g., soft combining) is applicable for the transmission in question. In an embodiment, the receiver can generate such feedback for one or more affected processes even if HARQ processing (e.g., soft combining) is not applicable for the transmission in question.

[0144] Block-related feedback (BRF) is disclosed herein. The receiver can generate BRF to indicate at least one of the following: a number of blocks (e.g., identified using a bitmap) that successfully decoded for a transmission, data block, process, or HARQ process in question; a number of missing decoded block(s) (e.g., distance from K) that enables the receiver to successfully decode data blocks for a transmission, data block, process, or HARQ process in question (e.g., identify the first missing block or missing block(s) using a bitmap); and / or feedback that is generated only if the number of missing blocks (e.g., distance from K) is less than a certain threshold (e.g., less than a certain fraction of the total number of blocks associated with the transmission), where the fraction and / or threshold can be a configured aspect of the WTRU 102. The feedback can be transmitted using an uplink control channel dedicated for this purpose, or piggybacked on another type of uplink transmission.

[0145] Processing by a transmitter to receive feedback is disclosed herein. The transmitter can receive HARQ feedback. Such feedback can be received using applicable HARQ feedback transmission and reception methods. For example, feedback can be received on a downlink control channel. In an embodiment, the feedback can be implied from received DCI that indicates retransmission processing for a particular transmission. Upon receiving HARQ feedback containing a negative acknowledgement, the WTRU 102 can determine to perform retransmission processing for the HARQ process in question.

[0146] As an example, in one or more embodiments, the WTRU can perform further transmission by selectively including certain blocks if the transmitter receives a BRF related to the process, and / or if the received control information indicates such selective retransmission. In one embodiment, the transmitter can determine that more than K blocks have been generated for the information bits associated with the process. In this case, the transmitter can determine that the further transmission for the process can include additional blocks that were not previously transmitted.

[0147] The transmitter can receive the BRF. The BRF feedback can be received using the applicable feedback transmission and reception methods, using control information piggybacked on a dedicated channel, or using control information piggybacked on another transmission. For example, the feedback can be received on a downlink control channel. In addition, if the received DCI indicates retransmission of one or more blocks associated with one or more processes, the DCI can also implicitly indicate such feedback. In this embodiment, the transmitter can determine the set of blocks to be selectively transmitted for one or more processes in accordance with the received feedback and / or downlink control information. The transmission can be constructed in a deterministic manner (e.g., based on the received control information), such that the receiver can determine the set of blocks and the one or more applicable processes. Alternatively, the transmitter can include the identity of the one or more applicable processes and / or the location of the blocks in the respective block sequence associated with the one or more applicable processes. In this case, the transmitter can determine which block to select from which process in accordance with the priority associated with each process, the time guarantee associated with the process, the SOM associated with the set of information bits, or other QoS parameters associated with the process / transmission itself and / or the data unit associated with the transmission process.

[0148] A 5G communication system design based on the methods and systems described herein can effectively support data transmissions with different requirements in terms of latency, throughput, and reliability. These requirements can be translated into different processing principles and transmission properties accordingly. For example, data associated with ultra-low latency and / or ultra-reliable use cases can be transmitted with very short transmission time intervals (TTIs), each of which has a modest payload, while data associated with mobile broadband or massive MTC use cases can be transmitted with longer TTIs in order to reduce control channel overhead.

[0149] Some data (e.g., associated with ultra-low latency or ultra-reliable use cases) can have to be transmitted with very tight latency requirements from the time it is generated by the application layer. This requirement can make it unacceptable to wait until the ongoing transmission using a larger TTI is finished. Given that latency sensitive traffic is typically sporadic, it would be very inefficient to reserve resources for exclusive use. Thus, a solution that allows transmitting latency sensitive data in resources used for ongoing transmissions while maintaining robust performance for all transmissions would be very useful.

[0150] While combinations have been described above, a person of ordinary skill in the art will recognize that each individual feature or element can be used alone or in any combination with other features and elements. In addition, the methods described herein can be implemented in computer programs, software, or firmware incorporated in computer- readable medium for execution by a computer or processor. Examples of computer- readable media include electronic signals (optical, electrical or electromagnetic) that are transmittable over a wire or wirelessly and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, removable floppy disks, RAM disks, hard disks, magnetic tapes, other magnetic media, optical media (e.g., compact disks), and digital versatile disks (DVDs). A processor in association with software can be used to implement a radio frequency transceiver for use in a WTRU 102, UE, terminal, base station, RNC, or any host computer.

Claims

1. A method implemented by a wireless transmit / receive unit (WTRU), the method comprising: The first transmission of a set of code blocks is received, wherein one or more code blocks from the set of code blocks are not successfully decoded; Send feedback in the bitmap associated with the one or more code blocks that were not successfully decoded; In a control channel transmission, control information for a second transmission is received, wherein the control information includes an indication that the code block set is within the second transmission, and wherein the control information includes a new data indicator indicating whether the code block set within the second transmission is used for retransmission; and Receive the second transmission.

2. The method according to claim 1, wherein, The first transmission was received before the second transmission.

3. The method according to claim 1, wherein, The control information is downlink control information (DCI).

4. The method according to claim 1, wherein, The bitmap includes identifiers of the one or more code blocks that were not successfully decoded.

5. The method according to claim 1, wherein, The feedback is a Hybrid Automatic Repeat Request (HARQ) feedback.

6. The method according to claim 1, wherein, The first transmission is a transmission of a transport block TB, wherein the TB includes the set of code blocks.

7. A wireless transmit / receive unit (WTRU), the WTRU comprising: processor; as well as A transceiver, operatively coupled to the processor, and configured to: The first transmission of a set of code blocks is received, wherein one or more code blocks from the set of code blocks are not successfully decoded; Send feedback in the bitmap associated with the one or more code blocks that were not successfully decoded; In a control channel transmission, control information for a second transmission is received, wherein the control information includes an indication that the code block set is within the second transmission, and wherein the control information includes a new data indicator indicating whether the code block set within the second transmission is used for retransmission; and Receive the second transmission.

8. The WTRU of claim 7, wherein the first transmission is received prior to the second transmission.

9. The WTRU of claim 8, wherein the feedback is a Hybrid Automatic Repeat Request (HARQ) feedback.

10. The WTRU of claim 7, wherein the control information is downlink control information (DCI).

11. The WTRU of claim 7, wherein the bit mapping includes an identifier of the one or more code blocks that were not successfully decoded.

12. The WTRU of claim 7, wherein the first transmission is a transmission of a transport block TB, and wherein the TB includes the set of code blocks.

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