WO2017078778A1 - Low latency data transmission in a control region for cellular wireless networks - Google Patents

Abstract

Apparatuses for evolved Node Bs (eNBs) and User Equipment (UEs) for transmission of low latency, non-control communication data through a control region are disclosed. An apparatus for an eNB includes control circuitry configured to generate control channel elements (CCEs) including low latency, non-control communication data instead of only control data, and cause the CCEs to be transmitted through the downlink control region to a UE. An apparatus for a UE includes control circuitry configured to decode control communications directed to the UE and received from evolved Node Bs through a downlink control region of a cellular wireless data network, and extract low latency, non-control communication data that has been substituted into the control communications instead of control data.

Description

LOW LATENCY DATA TRANSMISSION IN A CONTROL REGION FOR CELLULAR WIRELESS NETWORKS

Related Applications

[0001]This application claims priority to U.S. Provisional Application 62/250,701 , filed November 4, 2015, the entire disclosure of which is hereby incorporated herein by this reference.

Technical Field

[0002] This disclosure relates generally to the field of wireless communications, and more specifically to data transmission in a control region of cellular communication systems.

Background

[0003] In recent years, demand for access to fast mobile wireless data for mobile electronic devices has fueled the development of the 3rd Generation Partnership Project (3GPP) long term evolution (LTE) communication system (hereinafter "LTE system"). End users access the LTE system using mobile electronic devices (known as "user equipment" or "UE"), including appropriate electronics and software modules to communicate according to standards set forth by 3GPP.

Brief Description of the Drawings

[0004] FIG. 1 is a simplified illustration of channels of a downlink that may be used for communicating information in an LTE system.

[0005] FIG. 2 is a simplified block diagram of a cellular wireless communication system according to embodiments of the disclosure.

[0006] FIG. 3 is a simplified illustration of an example of a downlink that may be used in the cellular wireless communication system of FIG. 2 according to embodiments of the disclosure.

[0007] FIG. 4 is a simplified illustration of an example of a control region logical space of the downlink control region of FIG. 2 according to embodiments of the disclosure.

[0008] FIG. 5 is a simplified illustration of another example of a downlink that may be used in the cellular wireless communication system of FIG. 2 according to

embodiments of the disclosure. [0009] FIG. 6 is a simplified illustration of another example of a downlink that may be used in the cellular wireless communication system of FIG. 2 according to embodiments of the disclosure.

[0010] FIG. 7 is a simplified illustration of another example of a downlink that may be used in the cellular wireless communication system of FIG. 2 according to embodiments of the disclosure.

[0011] FIG. 8 illustrates, for some embodiments, example components of an electronic device according to embodiments of the disclosure.

[0012] FIG. 9 is a simplified flowchart illustrating a method of operating an eNB according to embodiments of the disclosure.

[0013] FIG. 10 is a simplified flowchart illustrating a method of operating a UE according to embodiments of the disclosure.

Detailed Description of Preferred Embodiments

[0014] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the present disclosure may be practiced. These embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice the disclosure made herein. It should be understood, however, that the detailed description and the specific examples, while indicating examples of embodiments of the disclosure, are given by way of illustration only, and not by way of limitation. From the disclosure, various substitutions, modifications, additions, rearrangements, or combinations thereof within the scope of the disclosure may be made and will become apparent to those of ordinary skill in the art.

[0015] In accordance with common practice, the various features illustrated in the drawings may not be drawn to scale. The illustrations presented herein are not meant to be actual views of any particular apparatus (e.g., device, system, etc.) or method, but are merely idealized representations that are employed to describe various embodiments of the disclosure. Accordingly, the dimensions of the various features may be arbitrarily expanded or reduced for clarity. In addition, some of the drawings may be simplified for clarity. Thus, the drawings may not depict all of the components of a given apparatus or all operations of a particular method.

[0016] Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof. Some drawings may illustrate signals as a single signal for clarity of presentation and description. It should be understood by a person of ordinary skill in the art that the signal may represent a bus of signals, wherein the bus may have a variety of bit widths and the present disclosure may be implemented on any number of data signals including a single data signal.

[0017] The various illustrative logical blocks, modules, circuits, and algorithm acts described in connection with embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and acts are described generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the embodiments of the disclosure described herein.

[0018] In addition, it is noted that the embodiments may be described in terms of a process that is depicted as a flowchart, a flow diagram, a structure diagram, a signaling diagram, or a block diagram. Although a flowchart or signaling diagram may describe operational acts as a sequential process, many of these acts can be performed in another sequence, in parallel, or substantially concurrently. In addition, the order of the acts may be re-arranged. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc. Furthermore, the methods disclosed herein may be implemented in hardware, software, or both. If implemented in software, the functions may be stored or transmitted as one or more

computer-readable instructions (e.g., software code) on a computer-readable medium. Computer-readable media includes both computer storage media (i.e., non-transitory media) and communication media including any medium that facilitates transfer of a computer program from one place to another.

[0019] Wireless mobile communication technology uses various standards and protocols governing communications between a base station and a wireless mobile device. For example, well-known standards include the 3rd Generation Partnership Project (3GPP) long term evolution (LTE), the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard, which is commonly known to industry groups as worldwide interoperability for microwave access (WiMAX), and the IEEE 802.1 1 standard, which is commonly known to industry groups as Wi-Fi. In 3GPP radio access networks (RANs) in LTE systems, the base station can include Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node Bs (also commonly denoted as evolved Node Bs, enhanced Node Bs, eNodeBs, or eNBs) and/or Radio Network Controllers (RNCs) in an E-UTRAN, which communicate with a wireless communication device, also known as user equipment (UE).

[0020] In cellular wireless networks that operate according to these standards, reducing data plane latency, and in particular air interface latency, may have significant benefits in the transmission of mobile broadband traffic. Some of these benefits may include increased user-perceived throughput, and increased user- perceived voice traffic (e.g., improved quality of experience and reduced call setup time). Moreover, sub-millisecond latency may enable a new class of services (e.g., mission critical communication) driven by extremely low latency.

[0021] One approach to reduce latency in a downlink may include shortening an LTE transmission time interval (TTI). By way of non-limiting example, the LTE TTI may be shortened from 1 millisecond (ms) to one symbol (e.g., an OFDM symbol of 0.07 ms) (e.g., during data communications through a physical downlink shared channel (PDSCH)). Also by way of non-limiting example, shortening an LTE TTI from 1 ms to two or more symbols (e.g., with a total TTI less than 1 ms) may also reduce latency. As used herein, the term "shortened TTI" refers to TTI of less than 1 ms. Also, as used herein, the term "low latency" refers to latency resulting from less than 1 ms TTI.

[0022] It may be relatively simple to implement shortened TTI for data

communications in the data region (e.g., PDSCH). It may be more complicated, however, to implement shortened TTI in the control region. Specifically, it may be desirable to maintain backwards compatibility with legacy LTE protocols and to enable low latency traffic to coexist with legacy LTE terminals (e.g., legacy UEs, legacy eNBs, etc.) in the same frequency band. These legacy LTE terminals may rely on some legacy control channels being operated according to legacy protocols without shortened TTI because legacy LTE terminals rely on information

communicated in the legacy control channels. For example, the downlink legacy control region includes a physical control format indicator channel (PCFICH), a physical hybrid-ARQ individual channel (PHICH), and a physical downlink control channel (PDCCH). Some resource elements in the downlink legacy control region may be occupied by these channels. Therefore, low latency data may not be transmitted during the first few (e.g., 1 -3) symbols of the legacy control region.

[0023] The unavailability of low latency data transmission during the first few symbols of the legacy control region may undermine the benefits of using short TTI for low latency data. Transmission of downlink control information in the legacy control region may itself even increase latency.

[0024] In some embodiments, disclosed is an apparatus for a User Equipment (UE), including control circuitry. The control circuitry is configured to decode control communications received from evolved Node Bs through a downlink control region of a cellular wireless data network that are directed to the UE. The control circuitry is also configured to extract low latency, non-control communication data that has been substituted into the control communications instead of the control data.

[0025] In some embodiments, disclosed is an apparatus for an evolved Node B (eNB), including control circuitry including a processor, and a non-transitory computer-readable medium operably coupled to the processor and including computer-readable instructions stored thereon. The computer-readable instructions are configured to instruct the processor to generate control channel elements

(CCEs) including low latency, non-control communication data instead of only control data, and cause the CCEs to be transmitted through a downlink control region to user equipment (UEs).

[0026] In some embodiments, disclosed is an apparatus for an evolved Node B (eNB), including control circuitry configured to control communication elements of the eNB to transmit PDCCH control channel elements (CCEs) including low latency UE data to user equipment (UEs) through a control region including a physical downlink control channel (PDCCH). The low latency UE data has a shortened transmission time interval (TTI) that is less than 1 millisecond (ms).

[0027] FIG. 1 is a simplified illustration of channels of a downlink 100 that may be used for communicating information in an LTE system. The downlink 100 includes a physical downlink control channel (PDCCH) region 140 and a physical downlink shared channel (PDSCH) region 150. The PDCCH region 140 is part of a downlink control region, and the PDSCH region 150 is part of a downlink data region. Shortened TTI transport blocks (TB) 160 may be communicated from an eNB to UEs in the PDSCH region 150 of the downlink 100.

[0028] While shortened (compared to legacy LTE) TTI may be used to reduce latency in the PDSCH region 150, there may not be any shortened TTI data communicated in the PDCCH region 140. Also, the UEs may not decode the shortened TTI data communicated in the PDSCH region 150 until control data from the downlink control region (e.g., the PDCCH region 140, a PCFICH region, and a PHICH region) has been accessed, which may occupy from 1 to 3 legacy LTE control symbols. Accordingly, while the total latency may be decreased slightly through the shortened TTI in the PDSCH region 150, the total decrease in latency resulting from the combined PDCCH region 140 and the PDSCH region 150 may be relatively small (e.g., less than an order of magnitude) because the legacy PDCCH region 140 remains the same as in legacy LTE systems. Embodiments disclosed herein propose new approaches for transmitting low latency data in the control region.

[0029] In some embodiments, disclosed herein is User Equipment (UE), including communication elements and control circuitry. The communication elements are configured to receive control communications from evolved Node Bs (eNBs) through a downlink control region of a cellular wireless data network. The control circuitry is configured to decode those of the control communications that are directed to the UE and extract low latency, non-control communication data that has been substituted into the control communications instead of control data.

[0030] In some embodiments, disclosed herein is an evolved Node B (eNB) including communication elements and control circuitry operably coupled to the

communication elements. The communication elements are configured to communicate with user equipment (UEs) through a downlink control region of a cellular wireless data network. The control circuitry includes at least one processor, and at least one non-transitory computer-readable medium operably coupled to the at least one processor. The at least one non-transitory computer-readable medium includes computer-readable instructions stored thereon. The computer-readable instructions are configured to instruct the at least one processor to generate control channel elements (CCEs) including low latency, non-control communication data instead of only control data. The computer-readable instructions are also configured to instruct the at least one processor to transmit the CCEs through the downlink control region to the UE.

[0031] In some embodiments disclosed herein is an evolved Node B (eNB) including communication elements, and control circuitry operably coupled to the

communication elements. The communication elements are configured to

communicate with user equipment (UEs) through a control region including a physical downlink control channel (PDCCH). The control circuitry is configured to control the communication elements to transmit PDCCH control channel elements (CCEs) including low latency UE data to the UEs. The low latency UE data has a shortened transmission time interval (TTI) that is less than 1 millisecond (ms).

[0032] As used herein, the term "control data" refers to data that is conventionally found in control region communications (e.g., PDCCH, PCFICH, PHICH).

Accordingly, the term "non-control communication data" refers to data that is not conventionally found in control region communications. A recitation herein stating that a communication includes non-control communication data merely indicates that at least some of the data included in the communication is non-control

communication data, and is not necessarily exclusive of control data. Accordingly, some of the data may be non-control communication data and some of the data may be control data in some instances. In other instances, all of the data may be non- control communication data.

[0033] As used herein, the term "legacy LTE" refers to LTE cellular wireless communication systems that were in operation according to current standards of the 3GPP as of the filing date of this application.

[0034] FIG. 2 is a simplified block diagram of a cellular wireless communication system 200 according to embodiments of the disclosure. The cellular wireless communication system 200 includes an evolved Node B (eNB) 210 and user equipment (UEs) 220 (sometimes referred to herein individually as "UE" 220). The eNB 210 is configured to communicate with the UEs 220 through a downlink 230. The downlink 230 includes a downlink control region 232 (e.g., including PDCCH, PCFICH, and PHICH) and a downlink data region 234 (e.g., including PDSCH).

[0035] The eNB 210 includes communication elements 218 configured to

communicate with communication elements 228 of the UEs 220 through the downlink 230. The eNB 210 also includes control circuitry 212 operably coupled to the communication elements. The control circuitry 212 includes at least one processor 214 (sometimes referred to herein as "processor" 214) and at least data storage device 216 (sometimes referred to herein as "storage" 216) (e.g., at least one non-transitory computer-readable medium) operably coupled to the processor 214. The storage 216 includes computer readable instructions configured to instruct the processor 214 to perform at least a portion of functions that the eNB 210 is configured to perform, as will be discussed herein in more detail. In some

embodiments, the control circuitry 212 may also include hardware elements (not shown) (e.g., integrated circuits, systems on chips (SOCs), field programmable gate arrays (FPGAs), other hardware elements, or combinations thereof) configured to perform at least a portion of the functions that the eNB 210 is configured to perform.

[0036] The UE 220 includes communication elements 218 configured to receive communications from the eNB 210 through the downlink 230. The UE 220 also includes control circuitry 222 operably coupled to the communication elements 228, similarly as discussed above with reference to the control circuitry 212 and the communication elements 218 of the eNB 210. Also, similar to the control circuitry 212, the control circuitry 222 includes at least one processor 224 and at least one data storage device 226 (e.g., at least one non-transitory computer-readable medium) operably coupled thereto. In some embodiments, the control circuitry 222 may also include one or more hardware elements (not shown). The control circuitry 222 is programmed (e.g., with computer-readable instructions stored on the storage 226, with hardware elements, etc.) to perform at least a portion of functions that the UE 220 is configured to perform, as will be discussed in more detail herein.

[0037] In some embodiments, the UEs 220 and the eNBs 210 are configured to enable low latency data transmission in the downlink control region 232. In combination with shortened TTI transmission in the data region (e.g., the PDSCH region), these UEs 220 and eNBs 210 may enable continuous low latency

transmission capability in the LTE downlink 230. Moreover, fast algorithms used for decoding PDCCH messages may be used to quickly process low latency data and to minimize changes in legacy UEs to implement UEs 220 according to the

embodiments disclosed herein.

[0038] Compared to legacy LTE, embodiments disclosed herein may allow data transmission within one or two orthogonal frequency division multiplexing (OFDM) symbols. Assuming that processing delay is three times data transmission delay (a legacy LTE assumption), legacy one way latency may be reduced from 1 + 3 = 4 ms in legacy LTE to 1 + 3 = 4 OFDM symbols (totaling about 0.28 ms, or a 93% reduction) according to embodiments of the disclosure.

[0039] Embodiments disclosed herein may be used in combination with shortened TTI during PDSCH. These embodiments may reduce even further the latency of using shortened TTI. Assuming a downlink control region 232 of three symbols, if the TTI is shortened to one symbol, and assuming three TTI processing delay, a worst case one way delay may be 3+1 +3=7 symbols (totaling about 0.5 ms). In some embodiments, since low latency data transmission in the downlink control region 232 may be available, the worst case one way delay may be 1 +3=4 symbols (totaling about 0.28 ms). Therefore, a significant reduction (e.g., about 44%) may be achieved by embodiments disclosed herein combined with shortened TTI, as compared to using shortened TTI in the downlink data region 234 alone.

[0040] In legacy LTE downlink transmission, the control region including PDCCH, PCFICH, and PHICH, may occupy one to three OFDM symbols, as specified by the PCFICH. During transmission of those symbols, no data transmission takes place. Resource elements (REs) in this control region may be organized in resource element groups (REGs) containing four REs each. Furthermore, nine REGs may together form one control channel element (CCE), and one or more CCEs may be used to transmit a downlink control information (DCI) message. A cyclic redundancy check (CRC) may be appended to the PDCCH payload and scrambled with a radio network temporary ID (RNTI) to allow a UE to perform blind decoding of DCI messages containing resource allocation or other control information such as uplink transmit power control. In order to save in UE complexity and power consumption, common and UE-specific search spaces may be defined with a limited number of PDCCH candidates.

[0041] Proposed in embodiments disclosed herein is low latency data transmission during PDCCH transmission. The low latency data transmission may be performed by substituting a portion of the REs in the downlink control region 232 with low latency transmit data (i.e., low latency non-control data). In some embodiments, transport block (TB) sizes and transmission formats (e.g., modulation and coding) for a new PDCCH-like low latency PDSCH (L-PDSCH) are defined. Such L-PDSCH may use existing or newly defined common or UE-specific search spaces for PDSCH transmission in the control region. The L-PDSCH may include low latency data rather than the DCI messages specified for legacy LTE systems. [0042] In some embodiments, unused REs in the downlink control region 232 may be substituted with low latency UE data according to a new format for transmission to the UEs 220.

[0043] In some embodiments, a portion of the REs in the downlink control region 232 may be punctured according to a puncturing pattern, regardless of whether any of the portion of REs were meant to carry control data. The punctured REs may be substituted with low latency UE data according to a new format for transmission to the UEs 220. The puncturing pattern may be pre-defined, semi=statically configured, or dynamically configured.

[0044] FIG. 3 is a simplified illustration of an example of a downlink 230A that may be used in the cellular wireless communication system 200 of FIG. 2. Referring to FIGS. 2 and 3 together, the downlink 230A includes a control region 332 and a PDSCH region 334. PDCCH CCEs 320 including downlink control Information (DCI) messages may be transmitted by the eNB 210 to the UEs 220 in the control region 332. The PDCCH CCEs 320 may be appended with CRC codes and scrambled with RNTIs.

[0045] L-PDSCH data units carrying shortened TTI non-control data in place of DCI messages may be transmitted to the UEs 220 in the control region 332 using

L-PDSCH CCEs 330 without scheduling grants. Similar to the PDCCH CCEs 320, quadrature phase-shift keying (QPSK) may be assumed for modulation of the

L-PDSCH CCEs 330 carrying the L-PDSCH data units. In order to accommodate the UEs 220 to perform blind decoding for different coding rates and TB sizes, search spaces for L-PDSCH, s^^Bs) (i.e., sets of L-PDSCH candidates to monitor) may be defined as a combination of a CCE aggregation level L (e.g., L ε {4,8,12,16}) and a TB size (TBS) index l_T'_BS (e.g., l_T'_BS ε {1,2,3,4,5}). Both common and

UE-specific search spaces may be defined to support common data transmission and UE-specific data transmission, respectively, for low latency small data

applications.

[0046] In some embodiments, CCEs corresponding to L-PDSCH candidate m of the search space S^"^/,rBs)may be given by

where N_{CCE k} is a total number of CCEs in the control region of subframe k, Y_k is a UE hashing function defined in Section 9.1 .1 of 3GPP TS 36.213, i = 0, ... , L - 1, m = 0, ... , ⁱ⁾ - 1, and ⁱ⁾ is a number of L-PDSCH candidates to monitor in the given search space, which may be the same for different TBS indices under a given CCE aggregation level. In some embodiments, the CCEs corresponding to

L-PDSCH candidate m of the search space s_{ ^L'^lTBS-^> may be given by

™-N_CCE,k

{(¾ + _TBSJ mod[N_CCE + i.

[0047] In some instances, it is possible that the UEs 220 may not be able to distinguish the detected CCE aggregation levels. For example, the UEs 220 may have multiple successful blind decoding results for different CCE aggregation levels with the same lowest CCE index. In some such instances, l_T'_BS may be signaled separately if a simple DCI format for L-PDSCH is used. Alternatively, the CCEs corresponding to L-PDSCH candidate m of the search space s '^lTBs) ma be given by one of:

(5L){(¾ + m)mod[N_CC£,fc/(5L)J} + i + L + l_T'_BS and

where l_T'_BS = {0,1,2,3,4}.

[0048] In some embodiments, search space based l_T'_BS indication may have an ambiguity issue. In some embodiments, another way to implicitly indicate l_T'_BS may be based on a "CCE index" for the PDCCH transmission (e.g., the lowest CCE index, n_CCE). For example, l_T'_BS = n_CCE mod (5).

[0049] Table 1 presents example L-PDSCH candidates monitored by the UEs 220 for different aggregation levels under the TBS index l_T'_BS, which may include 8 blind decoding per the TBS index.

Table 1 : Example L-PDSCH candidates monitored by a UE

[0050] Table 2 shows an example TB size table for L-PDSCH, where TB sizes are down-selected from Table 7.1 .7.2.1 -1 of 3GPP TS 36.212, assuming that transport block processing specified in Section 5.3.2 of 3GPP TS 36.212 may be employed for L-PDSCH. As 4 CCEs include 144 REs, which may be similar to the number of REs available in the data region of 1 PRB-pair, TB sizes for N_PRB = 1,2,3,4 in Table 7.1.7.2.1 -1 may be selected for L ε {4,8,12,16}. Alternatively, a new set of TB sizes for a set of selected target coding rates may be defined for L-PDSCH.

Table 2: Example transport block size table

[0051] In some embodiments, it may be assumed that a single TB size is used, and each aggregation level may result in a different code rate. In some embodiments, the TB size may be determined solely by the aggregation level.

[0052]After transport block processing, resulting L-PDSCH channel bits may be multiplexed with the PDCCH channel bits, and may be scrambled with a cell-specific sequence prior to modulation. Finally, REG-level interleaving specified in Section 6.8.5 of 3GPP TS 36.21 1 may be applied to the modulated and precoded symbols. Also, a CRC code may be appended to the L-PDSCH payload and may be xor-ed with a low latency UE RNTI.

[0053] FIGS. 4-6 illustrate example embodiments where a scheduler deliberately deallocates some PDCCH RE and reserves the de-allocated PDCCH RE for low latency data transmission. The resulting reserved RE may be used to transmit low latency data.

[0054] FIG. 4 is a simplified illustration of an example of a control region logical space 400 of the downlink control region 232 of FIG. 2. The control region logical space 400 of the example of FIG. 4 includes a legacy UE 1 search space 410, and a legacy UE 2 search space 440. A total number of CCEs allocated to PDCCH in the control region of a subframe k may be indicated by N_{CCE k}. A number of these CCEs that are occupied with PDCCH control data may be denoted by Nc_CE,k < ^NccE,k - A number of the CCEs, then, that are available for transmitting L-PDSCH data units is dentoed by N^cE.k = ^NccE,k ^{~ N}ccE,k - A first possible L-PDSCH search space 420 and a second possible L-PDSCH search space 430 may be defined within the available control region logical space 400. Low latency UEs 220 may receive semi- statically or dynamically from the eNB 210 an indication on at least one of N_C'_{CE k}, ^NccE,k _> ^anc' other parameters to determine CCE locations reserved for L-PDSCH.

[0055] Since UE search spaces may be randomized for every subframe, locations of L-PDSCH CCEs may be fixed, within the control region logical space 400, without compromising UE addressability. In some embodiments, calculation of UE search spaces for legacy UEs 410, 440 may not be modified, and may be done according to

[0056] Low latency UEs 220 may be configured to calculate a search space for L-PDSCH within the control region logical space 400. By way of non-limiting example, the control region logical space 400 may include a fixed, common

L-PDSCH search space 430 corresponding to a maximum allocation of CCEs for L-PDSCH. Also by way of non-limiting example, the control region logical space 400 may include a UE-specific search space 420, wherein CCEs corresponding to the L- PDSCH candidate m of the UE-specific search space are determined according to:

L{(¾ +

+ i, for / = 0, ... , L - 1 , where the CCE index refers to the allocation of L-PDSCH CCEs. Y_k may be a randomization parameter, and k may be the subframe index.

[0057] In order to simplify UE operation, it may be desirable that transport block (TB) sizes defined for data transmission in the control region correspond to TB sizes used in the data region (i.e. , they may be based on the same RE count). However, it may be possible to transmit smaller TB sizes within the control region due to a limited number of available REs. Multiples of CCE may be adopted as resource element allocations for an individual UE so that the search space definition L{(Y_k +

+ i ^{mav De} used. In such embodiments, example TB sizes as discussed above with reference to FIG. 3 may be used. Other resource element allocations may also be used.

[0058] In some embodiments, channel coding and rate matching operations may be performed according to the procedures described in TR 36.21 1 , § 5.1 .3 and § 5.1 .4. [0059] Blind decoding of common and UE-specific search spaces may be

accomplished as previously discussed with reference to FIG. 3. Such decoding and UE-specific search spaces may be carried out according to specified search spaces for L-PDSCH.

[0060] FIG. 5 is a simplified illustration of another example of a downlink 230B that may be used in the cellular wireless communication system 200 of FIG. 2. The downlink 230B includes a control region 590 (e.g., PDCCH, PCFICH, PHICH), and a PDSCH region 594. The control region 590 includes unallocated REs, as discussed above with reference to FIG. 4. Low latency data 596 may be substituted into the control region 590 for the unallocated REs 592.

[0061] FIG. 6 is a simplified illustration of another example of a downlink 230C that may be used in the cellular wireless communication system 200 of FIG. 2. Referring to FIGS. 2 and 6 together, the downlink 230C includes a control region 672 (e.g., PDCCH), and a PDSCH region 674. The control region 672 includes unallocated REs 676, as discussed above with reference to FIG. 4. In some embodiments, the unallocated REs 676 may be assigned using a DCI message in the PDCCH. In such embodiments, the UEs 220 may know that a low latency resource 676 has been allocated by checking the legacy PDCCH search space. An L-PDSCH resource may be indicated using a new DCI format, which may indicate the resource element allocation within the low latency CCEs (0, ... , Ν^Ε ^~ 1) f°^{r a} particular UE 220.

Different RNTIs (identifiers) may be used to distinguish PDCCHs for legacy PDSCH traffic 680 from PDCCHs for the L-PDSCH traffic 670.

[0062] FIG. 7 is a simplified illustration of another example of a downlink 230D that may be used in the cellular wireless communication system 200 of FIG. 2. The downlink 230D includes a control region 760 (e.g., PDCCH, PCFICH, PHICH) and a PDSCH region 762. Some REs 764 in the control region 760 may be punctured (not transmitted), according to a predefined pattern, and may be used to transmit low latency data 766. In other words, the REs 764 that fall within the predefined puncturing pattern are not transmitted, even if control data was intended to be carried in by such REs 764.

[0063] Legacy UEs may be unaware of the puncturing operation, and may attempt to decode the control channels as though no puncturing had occurred. In order to compensate for any control data that was not transmitted as a result of the punctured REs 764, the eNB 210 (FIG. 2) may transmit PDCCH with a higher aggregation level to enable the legacy UEs to satisfy error rate measurement requirements. UEs 220 (FIG. 2) that are programmed to recognize the puncturing pattern (for example, upon connection configuration) may treat the punctured REs 764 as neutral from a decoding perspective (i.e., as channel erasures).

[0064] Given that there are N_{CCE k} CCEs in the control region in subframe k, a total of ^NccE,k < NccE.k may be selected for L-PDSCH. Mapping of the A¾_fc CCEs to resource elements may be performed according to a randomized function. N^.k may vary dynamically, for example, to accommodate varying legacy PDCCH load or L-PDSCH load. Mapping from CCEs to punctured REs 764 may take into account the randomization function.

[0065] Similarly, as discussed above with reference to FIGS. 3-6, several options may be possible for resource allocation and data transmission. In some

embodiments, the UEs 220 may use blind decoding on the L-PDSCH search space and retrieve low latency data. In such embodiments, the UE search space within the ^NccE,k CCEs may be defined according to the examples discussed with reference to FIGS. 3-6. In some embodiments, the eNB 210 (FIG. 2) may use a new DCI format in the legacy PDCCH to signal an L-PDSCH resource allocation in the L-PDSCH resources.

[0066] As used herein, the term "circuitry" may refer to, be part of, or include an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), and/or memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the circuitry may be implemented in, or functions associated with the circuitry may be implemented by, one or more software or firmware modules. In some embodiments, circuitry may include logic, at least partially operable in hardware.

[0067] Embodiments described herein may be implemented into a system using any suitably configured hardware and/or software. FIG. 8 illustrates, for some

embodiments, example components of an electronic device 800. In some

embodiments, the electronic device 800 may be, may implement, may be

incorporated into, or otherwise may be a part of a user equipment (UE) (e.g., the UEs 220 of FIG. 2), an evolved NodeB (eNB) (e.g., the eNB 210 of FIG. 2), or some other suitable electronic device. In some embodiments, the electronic device 800 may include application circuitry 802, baseband circuitry 804, Radio Frequency (RF) circuitry 806, front-end module (FEM) circuitry 808 and one or more antennas 810, coupled together at least as shown in FIG. 8.

[0068] The application circuitry 802 may include one or more application processors. For example, the application circuitry 802 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with and/or may include memory/storage and may be configured to execute instructions stored in the memory/storage to enable various applications

and/or operating systems to run on the system.

[0069] The baseband circuitry 804 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 804 may include one or more baseband processors and/or control logic to process baseband signals received from a receive signal path of the RF circuitry 806 and to generate baseband signals for a transmit signal path of the RF circuitry 806. Baseband processing circuity 804 may interface with the application circuitry 802 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 806. For example, in some embodiments, the baseband circuitry 804 may include a second generation (2G) baseband processor 804A, third generation (3G) baseband processor 804B, fourth generation (4G) baseband processor 804C, and/or other baseband processor(s) 804D for other existing generations, generations in development, or generations to be developed in the future (e.g., fifth generation (5G), 6G, etc.). The baseband circuitry 804 (e.g., one or more of baseband processors 804A-D) may handle various radio control functions that

enable communication with one or more radio networks via the RF circuitry 806. The radio control functions may include, but are not limited to, signal

modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry 804 may include Fast-Fourier Transform (FFT), precoding, and/or constellation

mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry 804 may include convolution, tail-biting

convolution, turbo, Viterbi, and/or Low Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

[0070] In some embodiments, the baseband circuitry 804 may include elements of a protocol stack such as, for example, elements of an evolved universal terrestrial radio access network (EUTRAN) protocol including, for example, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and/or radio resource control (RRC) elements. A central processing unit (CPU) 804E of the baseband circuitry 804 may be configured to run elements of the protocol stack for signaling of the PHY, MAC, RLC, PDCP and/or RRC layers. In some embodiments, the baseband circuitry 804 may include one or more audio digital signal processor(s) (DSP) 804F. The audio DSP(s) 804F may include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments.

[0071] The baseband circuitry 804 may further include memory/storage 804G. The memory/storage 804G may be used to load and store data and/or instructions for operations performed by the processors of the baseband circuitry 804.

Memory/storage for one embodiment may include any combination of suitable volatile memory and/or non-volatile memory. The memory/storage 804G may include any combination of various levels of memory/storage including, but not limited to, read-only memory (ROM) having embedded software instructions (e.g., firmware), random access memory (e.g., dynamic random access memory (DRAM)), cache, buffers, etc. The memory/storage 804G may be shared among the various processors or dedicated to particular processors.

[0072] Components of the baseband circuitry may be suitably combined in a single chip, combined in a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry 804 and the application circuitry 802 may be

implemented together such as, for example, on a system on a chip (SOC).

[0073] In some embodiments, the baseband circuitry 804 may provide for

communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 804 may support communication with an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), or a wireless personal area network (WPAN). Embodiments in which the baseband circuitry 804 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry.

[0074] RF circuitry 806 may enable communication with wireless networks

using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 806 may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry 806 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 808 and provide baseband signals to the baseband circuitry 804. RF circuitry 806 may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband circuitry 804 and provide RF output signals to the FEM circuitry 808 for transmission.

[0075] In some embodiments, the RF circuitry 806 may include a receive signal path and a transmit signal path. The receive signal path of the RF circuitry 806 may include mixer circuitry 806A, amplifier circuitry 806B, and filter circuitry 806C. The transmit signal path of the RF circuitry 806 may include filter circuitry 806C and mixer circuitry 806A. RF circuitry 806 may also include synthesizer circuitry 806D for synthesizing a frequency for use by the mixer circuitry 806A of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 806A of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry 808 based on the synthesized frequency provided by synthesizer circuitry 806D. The amplifier circuitry 806B may be configured to amplify the down- converted signals, and the filter circuitry 806C may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down- converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry 804 for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry 806A of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

[0076] In some embodiments, the mixer circuitry 806A of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 806D to generate RF output signals for the FEM circuitry 808. The baseband signals may be provided by the baseband circuitry 804 and may be filtered by filter circuitry 806C. The filter circuitry 806C may include a low-pass filter (LPF), although the scope of the embodiments is not limited in this respect.

[0077] In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry 806A of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and/or upconversion

respectively. In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry 806A of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry 806A of the transmit signal path may be arranged for direct downconversion and/or direct upconversion, respectively. In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry 806A of the transmit signal path may be configured for super-heterodyne operation.

[0078] In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 806 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 804 may include a digital baseband interface to communicate with the RF circuitry 806.

[0079] In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

[0080] In some embodiments, the synthesizer circuitry 806D may be a fractional-N synthesizer or a fractional N/N+1 synthesizer, although the scope of the

embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 806D may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[0081] The synthesizer circuitry 806D may be configured to synthesize an output frequency for use by the mixer circuitry 806A of the RF circuitry 806 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 806D may be a fractional N/N+1 synthesizer. [0082] In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 804 or the applications processor 802 depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the applications processor 802.

[0083] Synthesizer circuitry 806D of the RF circuitry 806 may include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some

embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by either N or N+1 (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

[0084] In some embodiments, synthesizer circuitry 806D may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a local oscillator (LO) frequency

(fLO). In some embodiments, the RF circuitry 806 may include an IQ/polar converter.

[0085] FEM circuitry 808 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 810, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 806 for further processing. FEM circuitry 808 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 806 for transmission by one or more of the one or more antennas 810. [0086] In some embodiments, the FEM circuitry 808 may include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry 808 may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry 808 may include a low-noise amplifier (LNA) to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 806). The transmit signal path of the FEM circuitry 808 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 806), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 810).

[0087] In some embodiments, the electronic device 800 may include additional elements such as, for example, memory/storage, display, camera, sensor, and/or input/output (I/O) interface.

[0088] In embodiments where the electronic device 800 is, implements, is

incorporated into, or is otherwise part of an evolved NodeB (eNB), the RF circuitry 806 may be to receive and to send a signal. The baseband circuitry 804 may be to cause to transmit user data within a physical downlink control channel (PDCCH) region of the signal.

[0089] In embodiments where the electronic device 800 is, implements, is

incorporated into, or is otherwise part of a user equipment (UE), the RF circuitry 806 may be to receive a signal. The baseband circuitry 804 may be to cause to receive user data within a PDCCH region of the signal.

[0090] In some embodiments, the electronic device 800 of FIG. 8 may be configured to perform one or more processes, techniques, and/or methods as described herein, or portions thereof. One such method 900 is depicted in FIG. 9. FIG. 9 is a simplified flowchart of an example method 900 of operating an eNB. For example, the method 900 may include transmitting or causing to transmit 910, by the eNB, user data within the physical downlink control channel region (PDCCH) of a signal.

[0091] In some embodiments, the electronic device 800 of FIG. 8 may be configured to perform one or more processes, techniques, and/or methods as described herein, or portions thereof. One such method 1000 is depicted in FIG. 10. FIG. 10 is a simplified flowchart of a method 1000 of operating a UE. For example, the method 1000 may include receiving or causing to receive 1010, by a user equipment (UE) user data within a physical downlink control channel (PDCCH) region of a signal.

EXAMPLES [0092] The following is a list of example embodiments that fall within the scope of the disclosure. In order to avoid complexity in providing the disclosure, not all of the examples listed below are separately and explicitly disclosed as having been contemplated herein as combinable with all of the others of the examples listed below and other embodiments disclosed hereinabove. Unless one of ordinary skill in the art would understand that these examples listed below, and the above disclosed embodiments, are not combinable, it is contemplated within the scope of the disclosure that such examples and embodiments are combinable.

[0093] Example 1 : An apparatus for a User Equipment (UE), comprising: control circuitry configured to: decode control communications directed to the UE and received from evolved Node Bs through a downlink control region of a cellular wireless data network; and extract low latency, non-control communication data that has been substituted into the control communications instead of control data.

[0094] Example 2: The apparatus of Example 1 , wherein the low latency, non- control communication data includes shortened transmission time interval (TTI) physical downlink shared channel (PDSCH) data elements.

[0095] Example 3: The apparatus according to any one of Examples 1 and 2, wherein the low latency, non-control communication data is coded using quadrature phase shift keying (QPSK).

[0096] Example 4: The apparatus according to any one of Examples 1 -3, wherein the control circuitry is configured to perform blind decoding over a given search space to decode those of the control communications that are directed to the UE.

[0097] Example 5: The apparatus according to any one of Examples 1 -4, wherein the low latency, non-control communication data is substituted into the control communications in place of a downlink control information (DCI) message of a physical downlink control channel (PDCCH) of the downlink control region.

[0098] Example 6: The apparatus of Example 5, wherein the low latency,

non-control communication data is received without scheduling grants.

[0099] Example 7: The apparatus according to any one of Examples 1 -4, wherein the low latency, non-control communication data is substituted into the control communications in place of one or more resource elements (REs) of a physical downlink control channel of the downlink control region.

[00100] Example 8: The apparatus of Example 7, wherein the one or more REs include REs that were unused for delivering control data and de-allocated and reserved for carrying the low latency, non-control communication data, further comprising that the UE is configured to receive semi-statically or dynamically an indication on at least one of parameters related to determining locations of the deallocated REs.

[00101] Example 9: The apparatus of Example 7, wherein the one or more REs include REs selected according to a puncturing pattern regardless of whether or not the REs would have been used for delivering control data, wherein the puncturing pattern is one of pre-defined, semi-statically configured, or dynamically configured.

[00102] Example 10: The apparatus of Example 9, wherein the control circuitry is configured to treat the REs as neutral from a decoding perspective.

[00103] Example 1 1 : An apparatus for an evolved Node B (eNB), comprising: control circuitry comprising: a processor; and a computer-readable medium operably coupled to the processor and including computer readable instructions stored thereon, the computer-readable instructions configured to instruct the processor to: generate control channel elements (CCEs) including low latency, non control communication data instead of only control data; and cause the CCEs to be transmitted through a downlink control region to user equipment (UEs).

[00104] Example 12: The apparatus of Example 1 1 , wherein the control circuitry further comprises a means for defining transport block (TB) sizes and transmission formats.

[00105] Example 13: The apparatus according to of any one of Examples 1 1 and 12, wherein the computer-readable instructions are configured to instruct the at least one processor to substitute at least a portion of bits of a downlink control information (DCI) message with the low latency non-control communication data.

[00106] Example 14: The apparatus according to any one of Examples 1 1 and 12, wherein the computer-readable instructions are configured to instruct the at least one processor to substitute the low latency non-control communication data for resource elements (REs) of the CCEs.

[00107] Example 15: The apparatus of Example 14, wherein the

computer-readable instructions are configured to instruct the at least one processor to indicate to the UEs which of the REs have been substituted with the low latency non-control communication data using downlink control information (DCI) messages.

[00108] Example 16: The apparatus of Example 15, wherein the

computer-readable instructions are configured to instruct the at least one processor to append a cyclic redundancy check (CRC) code to the DCI messages and xor the appended CRC with a low latency UE radio network temporary identifier (RNTI).

[00109] Example 17: The apparatus of Example 14, wherein the computer- readable instructions are configured to instruct the at least one processor to substitute REs that were unused for transmitting control data with the low latency non-control communication data.

[00110] Example 18: The apparatus of Example 14, wherein the

computer-readable instructions are configured to instruct the at least one processor to substitute REs selected according to a puncturing pattern with the low latency, non-control communication data regardless of whether or not the REs would have otherwise been used for delivering control data.

[00111] Example 19: The apparatus of Example 18, wherein the

computer-readable instructions are configured to instruct the at least one processor to increase a CCE aggregation level of a physical downlink control channel to compensate for control data that is not delivered because of the puncturing pattern.

[00112] Example 20: The apparatus according to either one of Examples 18 and 19, wherein the computer-readable instructions are configured to instruct the at least one processor to map the CCEs to the REs according to a randomized function.

[00113] Example 21 : The apparatus according to any one of Examples 18-20, wherein the computer-readable instructions are configured to instruct the at least one processor to vary mapping of the CCEs to the REs dynamically.

[00114] Example 22: An apparatus for an evolved Node B (eNB), comprising: control circuitry configured to control communication elements of the eNB to transmit physical downlink control channel (PDCCH) control channel elements (CCEs) including low latency user equipment (UE) data to UEs through a control region including a PDCCH; wherein the low latency UE data has a shortened transmission time interval (TTI) that is less than 1 millisecond (ms).

[00115] Example 23: The apparatus of Example 22, wherein the control circuitry is configured to control the communication elements to transmit the low latency UE data within downlink control information (DCI) messages.

[00116] Example 24: The apparatus of Example 22, wherein the control circuitry is configured to control the communication elements to transmit the low latency UE data in place of resource elements (REs) of the PDCCH CCEs. [00117] Example 25: The apparatus of Example 22, wherein the control circuitry is configured to control the communication elements to transmit other low latency UE data to the UEs through a data region.

[00118] Example 26: A method of operating a User Equipment (UE), comprising: decoding control communications directed to the UE and received from evolved Node Bs through a downlink control region of a cellular wireless data network; and extracting low latency, non-control communication data that has been substituted into the control communications instead of control data.

[00119] Example 27: The method of Example 26, wherein extracting low latency, non-control communication data comprises extracting shortened transmission time interval (TTI) physical downlink shared channel (PDSCH) data elements.

[00120] Example 28: The method according to either one of Examples 26 and 27, wherein extracting low latency, non-control communication data comprises extracting low latency, non-control communication data that is coded using quadrature phase shift keying (QPSK).

[00121] Example 29: The method according to any one of Examples 26-28, wherein decoding control communications comprises blindly decoding the control communications over a given search space to decode those of the control communications that are directed to the UE.

[00122] Example 30: The method according to any one of Examples 26-29, wherein extracting low latency, non-control communication data comprises extracting low latency, non-control communication data that is substituted into the control communications in place of a downlink control information (DCI) message of a physical downlink control channel (PDCCH) of the downlink control region.

[00123] Example 31 : The method of Example 30, further comprising receiving the low latency, non-control communication data without scheduling grants.

[00124] Example 32: The method according to any one of Examples 26-29, wherein extracting low latency, non-control communication data comprises extracting low latency, non-control communication data that is substituted into the control communications in place of one or more resource elements (REs) of a physical downlink control channel of the downlink control region.

[00125] Example 33: The method of Example 32, wherein extracting low latency, non-control communication data that is substituted into the control communications in place of one or more resource elements (REs) comprises extracting the low-latency, non-control communication data that is substituted into the control communications in place of REs that were unused for delivering control data and de-allocated and reserved for carrying the low latency, non-control communication data; and receiving semi-statically or dynamically an indication on at least one of parameters related to determining locations of the de-allocated REs.

[00126] Example 34: The method of Example 32, wherein extracting low latency, non-control communication data that is substituted into the control communications in place of one or more resource elements (REs) comprises extracting the low- latency, non-control communication data that is substituted into the control communications in place of REs selected according to a puncturing pattern regardless of whether or not the REs would have been used for delivering control data, wherein the puncturing pattern is one of pre-defined, semi-statically configured, or dynamically configured.

[00127] Example 35: The method according to any one of Examples 32-34, further comprising treating the REs as neutral from a decoding perspective.

[00128] Example 36: A method of operating an evolved Node B (eNB),

comprising: control circuitry comprising: generating control channel elements (CCEs) including low latency, non control communication data instead of only control data; and causing the CCEs to be transmitted through a downlink control region to user equipment (UEs).

[00129] Example 37: The method of Example 36, further comprising defining transport block (TB) sizes and transmission formats.

[00130] Example 38: The method according to any one of Examples 36-37, wherein generating CCEs including low latency, non-control communication data comprises substituting at least a portion of bits of a downlink control information (DCI) message with the low latency non-control communication data.

[00131] Example 39: The method according to any one of Examples 36-38, wherein generating CCEs including low latency, non-control communication data comprises substituting the low latency non-control communication data for resource elements (REs) of the CCEs.

[00132] Example 40: The method of Example 39, further comprising indicating to the UEs which of the REs have been substituted with the low latency non-control communication data using downlink control information (DCI) messages. [00133] Example 41 : The method of Example 40, further comprising appending a cyclic redundancy check (CRC) code to the DCI messages and xor the appended CRC with a low latency UE radio network temporary identifier (RNTI).

[00134] Example 42: The method according to any one of Examples 39-41 , wherein substituting the low latency non-control communication data for REs of the CCEs comprises substituting REs that were unused for transmitting control data with the low latency non-control communication data.

[00135] Example 43: The method of Example 39, wherein substituting the low latency non-control communication data for REs of the CCEs comprises substituting REs selected according to a puncturing pattern with the low latency, non-control communication data regardless of whether or not the REs would have otherwise been used for delivering control data.

[00136] Example 44: The method of Example 43, further comprising increasing a

CCE aggregation level of a physical downlink control channel to compensate for control data that is not delivered because of the puncturing pattern.

[00137] Example 45: The method according to any one of Examples 43 and 44, further comprising mapping the CCEs to the REs according to a randomized function.

[00138] Example 46: The method according to any one of Examples 43-45, further comprising varying mapping of the CCEs to the REs dynamically.

[00139] Example 47: A method of operating an evolved Node B (eNB), comprising transmitting physical downlink control channel (PDCCH) control channel elements

(CCEs) including low latency user equipment (UE) data to UEs through a control region including a PDCCH, wherein the low latency UE data has a shortened transmission time interval (TTI) that is less than 1 millisecond (ms).

[00140] Example 48: The method of Example 47, wherein transmitting physical downlink control channel (PDCCH) control channel elements (CCEs) including low latency user equipment (UE) data to UEs comprises transmitting the low latency UE data within downlink control information (DCI) messages.

[00141] Example 49: The method of Example 47, wherein transmitting physical downlink control channel (PDCCH) control channel elements (CCEs) including low latency user equipment (UE) data to UEs comprises transmitting the low latency UE data in place of resource elements (REs) of the PDCCH CCEs. [00142] Example 50: The method of Example 47, further comprising transmitting other low latency UE data to the UEs through a data region.

[00143] Example 51 : A non-transitory computer-readable storage medium comprising computer-readable instructions stored thereon, the computer-readable instructions configured to instruct a processor to perform the method according to any one of Examples 26-50.

[00144] Example 52: A means for performing the method according to any one of Examples 26-50.

[00145] Example 53: A method for cellular communications, where the user data is transmitted within the downlink control region of LTE.

[00146] Example 54: The method according to Example 53 or some other example herein, where a new PDCCH-like low latency PDSCH (L-PDSCH) is defined which uses existing or newly defined common or UE-specific search spaces for PDSCH transmission in the control region, but contains low latency data rather than the DCI messages specified in LTE.

[00147] Example 55: The method according to Example 54 or some other example herein, where transport block (TB) sizes and transmission formats

(e.g., modulation and coding) are defined as described in this disclosure.

[00148] Example 56: The method according to Example 53 or some other example herein, consisting in the utilization of unused REs in the downlink control region for low latency UE data transmission (L-PDSCH) according to a new format as described in this disclosure.

[00149] Example 57: The method according to Example 53 or some other example herein, consisting of puncturing an RE in the downlink control region for low latency UE data transmission (L-PDSCH) according to a new or existing format as described in this disclosure.

[00150] Example 58: The method according to Examples 54-57 or some other example herein, where the resource elements for data transmission within the downlink control region (L-PDSCH) are determined through a blind decoding procedure over a given search space.

[00151] Example 59: The method according to Example 58 or some other example herein, where fixed or randomized search spaces for low latency

data transmission in the control region are determined as defined in this disclosure. [00152] Example 60: The method according to Examples 56-57 or some other example herein, where the resource elements used for data transmission in the downlink control region are indicated with a new DCI format.

[00153] Example 61 : Base station equipment and circuitry to transmit wireless signals according to methods in Examples 52-60.

[00154] Example 62: User equipment and circuitry to receive wireless signals according to methods in Examples 52-60.

[00155] Example 63: An evolved NodeB (eNB) apparatus to reduce latency in data transmission, comprising: radio frequency (RF) circuitry to receive and to send a signal; and baseband circuitry coupled with the RF circuitry, the baseband circuitry to cause to transmit user data within a physical downlink control channel (PDCCH) region of the signal.

[00156] Example 64: The eNB apparatus of Example 63, or of some other example herein, wherein the baseband circuitry is further to transmit the user data in search spaces of the PDCCH region.

[00157] Example 65: The eNB apparatus of Example 64, or of some other example herein, wherein the search spaces of the PDCCH are defined by legacy, common or user equipment (UE) specific search spaces.

[00158] Example 66: The eNB apparatus of Example 64, or of some other example herein, wherein the baseband circuitry is further to cause to transmit the user data in the PDCCH without scheduling grants.

[00159] Example 67: The eNB apparatus of Example 64, or of some other example herein, wherein search spaces * are defined as a combination of a control channel element (CCE) aggregation level L and a transport block size (TBS) index ^Itbs .

[00160] Example 68: The eNB apparatus of Example 67, or of some other example herein, wherein the aggregation level L further includes ^{i e} {⁴Ai2,i6} _anc|/_or the TBS index ^Itbs further includes {½³A5} _

[00161] Example 69: The eNB apparatus of Example 63, or of some other example herein, wherein the baseband circuitry is further to de-allocate PDCCH resource elements (REs) for low latency data transmission and to cause to transmit semi-statically or dynamically an indication on at least one of parameters related to determining locations of the de-allocated REs.. [00162] Example 70: The eNB apparatus of Example 63, or of some other example herein, wherein baseband circuitry is further to cause to transmit, to a low latency user equipment (LUE), assignment of PDCCH RE for low latency data transmission using a downlink control information (DCI) message in the PDCCH.

[00163] Example 71 : A method for reducing latency in data transmission by an eNB, comprising: transmitting or causing to transmit, by the eNB, user data within the physical downlink control channel (PDCCH) region of a signal.

[00164] Example 72: The method of Example 71 or some other example herein, wherein transmitting or causing to transmit user data within the PDCCH further includes transmitting or causing to transmit user data in search spaces of the PDCCH region.

[00165] Example 73: The method of Example 72 or some other example herein, wherein the search spaces of the PDCCH are defined by legacy, newly-defined common or UE-specific search spaces.

[00166] Example 74: The method of Example 72, or of some other example herein, wherein transmitting or causing to transmit user data in search spaces of the PDCCH region further includes transmitting or causing to transmit the user data in the PDCCH without scheduling grants.

[00167] Example 75: The method of Example 72, or of some other example herein, wherein search spaces ^¾ are defined as a combination of a control channel element (CCE) aggregation level L and a transport block size (TBS) index r

[00168] Example 76: The method of Example 75, or of some other example herein, wherein the aggregation level L further includes ^{L E} {^4>8>i2,i6} and/or the TBS index ⁷^ further includes ^ ^e {½³A5} _

[00169] Example 77: A UE apparatus for reducing latency in data transmission, comprising: radio frequency (RF) circuitry to receive a signal; and baseband circuitry coupled with the RF circuitry, the baseband circuitry to cause to receive user data within a PDCCH region of a signal.

[00170] Example 78: The UE apparatus of Example 77 or any other example herein, wherein the baseband circuitry is further to receive the user data in search spaces of the PDCCH region. [00171] Example 79: The UE apparatus of Example 78 or some other example herein, wherein the search spaces of the PDCCH are defined by legacy, common or UE-specific search spaces.

[00172] Example 80: The UE apparatus of Example 78 or some other example herein, wherein the common or the UE-specific search spaces are defined within a subset of PDCCH candidates.

[00173] Example 81 : The UE apparatus of Example 78 or some other example herein, wherein the baseband circuitry is further to determine if a low latency resource has been allocated based on an identified DCI message in the PDCCH.

[00174] Example 82: A method for reducing latency in data transmission by a UE, comprising: receiving or causing to receive, by the UE, user data within a PDCCH region of a signal.

[00175] Example 83: The method of Example 82, or of any other example herein, further comprising receiving or causing to receive, by the UE, the user data in search spaces of the PDCCH region.

[00176] Example 84: The method of Example 82 or some other example herein, wherein the search spaces of the PDCCH are defined by legacy, common or UE- specific search spaces.

[00177] Example 85: The method of Example 82 or some other example herein, wherein the common or the UE-specific search spaces are defined within a subset of PDCCH candidates.

[00178] Example 86: The UE apparatus of Example 82 or some other example herein, further comprising determining if a low latency resource has been allocated based on the identification of a DCI message in the PDCCH.

[00179] Example 87: An apparatus comprising a means to perform one or more elements of a method described in or related to any of Examples 53-86, or any other method or process described herein.

[00180] Example 88: One or more non-transitory computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of a method described in or related to any of Examples 52-86, or any other method or process described herein. [00181] Example 89: An apparatus comprising logic, modules, and/or circuitry to perform one or more elements of a method described in or related to any of

Examples 53-86, or any other method or process described herein.

[00182] Example 90: A method, technique, or process as described in or related to any of Examples 53-86, or portions or parts thereof.

[00183] Example 91 : An apparatus comprising: one or more processors and one or more computer readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform the method, techniques, or process as described in or related to any of Examples 53-86, or portions thereof.

[00184] Example 92: A method of communicating in a wireless network as shown and described herein.

[00185] Example 93: A system for providing wireless communication as shown and described herein.

[00186] Example 94: A device for providing wireless communication as shown and described herein.

[00187] While certain illustrative embodiments have been described in connection with the figures, those of ordinary skill in the art will recognize and appreciate that embodiments encompassed by the disclosure are not limited to those embodiments explicitly shown and described herein. Rather, many additions, deletions, and modifications to the embodiments described herein may be made without departing from the scope of embodiments encompassed by the disclosure, such as those hereinafter claimed, including legal equivalents. In addition, features from one disclosed embodiment may be combined with features of another disclosed embodiment while still being encompassed within the scope of embodiments encompassed by the disclosure, as contemplated by the inventors.

Claims

Claims

1 . An apparatus for a User Equipment (UE), comprising:

control circuitry configured to:

decode control communications directed to the UE and received from evolved Node Bs through a downlink control region of a cellular wireless data network; and

extract low latency, non-control communication data that has been substituted into the control communications instead of control data.

2. The apparatus of claim 1 , wherein the low latency, non-control communication data includes shortened transmission time interval (TTI) physical downlink shared channel (PDSCH) data elements.

3. The apparatus of claim 1 , wherein the low latency, non-control communication data is coded using quadrature phase shift keying (QPSK).

4. The apparatus of claim 1 , wherein the control circuitry is configured to perform blind decoding over a given search space to decode those of the control communications that are directed to the UE.

5. The apparatus according to any one of claims 1 -4, wherein the low latency, non-control communication data is substituted into the control

communications in place of a downlink control information (DCI) message of a physical downlink control channel (PDCCH) of the downlink control region.

6. The apparatus of claim 5, wherein the low latency, non-control communication data is received without scheduling grants.

7. The apparatus according to any one of claims 1 -4, wherein the low latency, non-control communication data is substituted into the control

communications in place of one or more resource elements (REs) of a physical downlink control channel of the downlink control region.

8. The apparatus of claim 7, wherein the one or more REs include REs that were unused for delivering control data and de-allocated and reserved for carrying the low latency, non-control communication data, further comprising that the UE is configured to receive semi-statically or dynamically an indication on at least one of parameters related to determining locations of the de-allocated REs.

9. The apparatus of claim 7, wherein the one or more REs include REs selected according to a puncturing pattern regardless of whether or not the REs would have been used for delivering control data, wherein the puncturing pattern is one of pre-defined, semi-statically configured, or dynamically configured.

10. The apparatus of claim 9, wherein the control circuitry is configured to treat the REs as neutral from a decoding perspective.

1 1 . An apparatus for an evolved Node B (eNB), comprising:

control circuitry comprising:

a processor; and

a computer-readable medium operably coupled to the processor and including computer-readable instructions stored thereon, the computer-readable instructions configured to instruct the processor to:

generate control channel elements (CCEs) including low latency,

non-control communication data instead of only control data; and

cause the CCEs to be transmitted through a downlink control region to user equipment (UEs).

12. The apparatus of claim 1 1 , wherein the control circuitry further comprises a means for defining transport block (TB) sizes and transmission formats.

13. The apparatus according to of any one of claims 1 1 and 12, wherein the computer-readable instructions are configured to instruct the at least one processor to substitute at least a portion of bits of a downlink control information (DCI) message with the low latency non-control communication data.

14. The apparatus according to any one of claims 1 1 and 12, wherein the computer-readable instructions are configured to instruct the at least one processor to substitute the low latency non-control communication data for resource elements (REs) of the CCEs.

15. The apparatus of claim 14, wherein the computer-readable instructions are configured to instruct the at least one processor to indicate to the UEs which of the REs have been substituted with the low latency non-control communication data using downlink control information (DCI) messages.

16. The apparatus of claim 15, wherein the computer-readable instructions are configured to instruct the at least one processor to append a cyclic redundancy check (CRC) code to the DCI messages and xor the appended CRC with a low latency UE radio network temporary identifier (RNTI).

17. The apparatus of claim 14, wherein the computer-readable instructions are configured to instruct the at least one processor to substitute REs that were unused for transmitting control data with the low latency non-control communication data.

18. The apparatus of claim 14, wherein the computer-readable instructions are configured to instruct the at least one processor to substitute REs selected according to a puncturing pattern with the low latency, non-control communication data regardless of whether or not the REs would have otherwise been used for delivering control data.

19. The apparatus of claim 18, wherein the computer-readable instructions are configured to instruct the at least one processor to increase a CCE aggregation level of a physical downlink control channel to compensate for control data that is not delivered because of the puncturing pattern.

20. The apparatus of claim 18, wherein the computer-readable instructions are configured to instruct the at least one processor to map the CCEs to the REs according to a randomized function.

21 . The apparatus of claim 18, wherein the computer-readable instructions are configured to instruct the at least one processor to vary mapping of the CCEs to the REs dynamically.

22. An apparatus for an evolved Node B (eNB), comprising:

control circuitry configured to control communication elements of the eNB to transmit physical downlink control channel (PDCCH) control channel elements (CCEs) including low latency user equipment (UE) data to UEs through a control region including a PDCCH;

wherein the low latency UE data has a shortened transmission time interval (TTI) that is less than 1 millisecond (ms).

23. The apparatus of claim 22, wherein the control circuitry is configured to control the communication elements to transmit the low latency UE data within downlink control information (DCI) messages.

24. The apparatus of claim 22, wherein the control circuitry is configured to control the communication elements to transmit the low latency UE data in place of resource elements (REs) of the PDCCH CCEs.

25. The apparatus of claim 22, wherein the control circuitry is configured to control the communication elements to transmit other low latency UE data to the UEs through a data region.