Apparatus and method for narrowband definition for enhanced machine type communications

Abstract

The present invention relates to narrowband definition for enhanced machine type communication. Aspects of the present disclosure provide a method for being performed by a wireless device. The method generally includes identifying one or more narrowband regions within a wider system bandwidth based on an amount of available resources in the system bandwidth, and using at least one of the identified narrowband regions for communication.

Description

[0001] This application is a divisional application of an invention patent application with an international application date of March 11, 2016 and application number 201680027698.3 (international application number PCT / US2016 / 021936) and entitled “Method and Apparatus for Narrowband Definition for Enhanced Machine Type Communications”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to U.S. Patent Application No. 15 / 067,029, filed on March 10, 2016, which in turn claims the benefit of U.S. Provisional Patent Application No. 62 / 162,623, filed on May 15, 2015, which is hereby incorporated by reference in its entirety. Technical Field

[0004] Certain aspects of the present disclosure relate generally to wireless communications and, more particularly, to narrowband definitions for enhanced machine type communications (eMTC). Background Art

[0005] Wireless communication systems are widely deployed to provide various types of communication content such as voice, data, etc. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, third generation partnership project (3GPP) long term evolution (LTE) / LTE-Advanced systems, and orthogonal frequency division multiple access (OFDMA) systems.

[0006] In general, a wireless multiple access communication system can support the communication of multiple wireless terminals simultaneously. Each terminal communicates with one or more base stations via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from the base station to the terminal, while the reverse link (or uplink) refers to the communication link from the terminal to the base station. Such communication links can be established via single-input single-output, multiple-input single-output, or multiple-input multiple-output (MIMO) systems.

[0007] A wireless communication network may include several base stations that can support communications among several wireless devices. The wireless devices may include user equipment (UE). Some UEs may be considered to be enhanced or evolved machine type communication (eMTC) UEs, which may communicate with a base station, another device (e.g., a remote device), or some other entity. MTC may refer to communications involving at least one remote device at at least one end of the communication, and may include forms of data communications involving one or more entities that do not necessarily require human-computer interaction. MTC UEs may include UEs capable of MTC communications with an MTC server and / or other MTC devices via, for example, a public land mobile network (PLMN). Summary of the invention

[0008] Certain aspects of the present disclosure provide a method for execution by a wireless device. The method generally includes identifying one or more narrowband regions within a wider system bandwidth based on an amount of available resources in the system bandwidth, and communicating using at least one of the identified narrowband regions.

[0009] Certain aspects of the present disclosure provide an apparatus for wireless communication. The apparatus generally includes: at least one processor configured to identify one or more narrowband regions within a wider system bandwidth based on an amount of available resources in the system bandwidth, and to communicate using at least one of the identified narrowband regions; and a memory coupled to the at least one processor.

[0010] Certain aspects of the present disclosure provide an apparatus for wireless communication. The apparatus generally includes means for identifying one or more narrowband regions within a wider system bandwidth based on an amount of available resources in the system bandwidth, and means for communicating using at least one of the identified narrowband regions.

[0011] Certain aspects of the present disclosure provide a computer-readable medium for wireless communications. The computer-readable medium generally includes code for identifying one or more narrowband regions within a wider system bandwidth based on an amount of available resources in the system bandwidth, and code for communicating using at least one of the identified narrowband regions.

[0012] Numerous other aspects are provided, including methods, apparatus, systems, computer program products, and processing systems. To achieve the foregoing and related purposes, one or more aspects include features fully described below and particularly pointed out in the appended claims. The following description and accompanying drawings set forth in detail certain illustrative features of the one or more aspects. However, these features are merely indicative of several of the various ways in which the principles of the various aspects may be employed, and the present description is intended to cover all such aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a block diagram conceptually illustrating an example of a wireless communication network in accordance with certain aspects of the present disclosure.

[0014] Figure 2 Shown is a block diagram conceptually illustrating an example of a base station in communication with a user equipment (UE) in a wireless communication network in accordance with certain aspects of the present disclosure.

[0015] Figure 3 is a block diagram conceptually illustrating an example of a frame structure in a wireless communication network in accordance with certain aspects of the present disclosure.

[0016] Figure 4 is a block diagram conceptually illustrating two exemplary subframe formats with a normal cyclic prefix.

[0017] Figure 5 Exemplary subframe configurations for eMTC are illustrated in accordance with certain aspects of the present disclosure.

[0018] Figure 6 is a flow diagram illustrating example operations for wireless communications by a wireless device in accordance with certain aspects of the present disclosure.

[0019] Figure 7 Exemplary resource block configurations for eMTC operations are illustrated in accordance with certain aspects of the present disclosure.

[0020] Figures 8A-8C Example narrowband region definitions in accordance with certain aspects of the present disclosure are illustrated.

[0021] Figures 9A-9C Example narrowband region definitions in accordance with certain aspects of the present disclosure are illustrated. DETAILED DESCRIPTION

[0022] Aspects of the present disclosure provide narrowband regions that may be used to define enhanced machine type communications (eMTC) performed by wireless devices.

[0023] The techniques described herein may be used for various wireless communication networks, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and other networks. The terms "network" and "system" are often used interchangeably. A CDMA network may implement radio technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, and the like. UTRA includes Wideband CDMA (WCDMA), Time Division Synchronous CDMA (TD-SCDMA), and other CDMA variants. cdma2000 covers IS-2000, IS-95, and IS-856 standards. TDMA networks may implement radio technologies such as Global System for Mobile Communications (GSM). OFDMA networks may implement radio technologies such as Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Radio technologies such as LTE and GSM are used in the UMTS. UTRA and E-UTRA are parts of the Universal Mobile Telecommunications System (UMTS). 3GPP Long Term Evolution (LTE) and Advanced LTE (LTE-A) in both frequency division duplex (FDD) and time division duplex (TDD) are new versions of UMTS using E-UTRA, which adopt OFDMA on the downlink and SC-FDMA on the uplink. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSM are described in documents from an organization named "3rd Generation Partnership Project" (3GPP). Cdma2000 and UMB are described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP2). The technology described herein can be used for the wireless networks and radio technologies mentioned above and other wireless networks and radio technologies. For clarity, certain aspects of these technologies are described below for LTE / Advanced LTE, and LTE / Advanced LTE terms are used in most of the following descriptions. LTE and LTE-A are generally referred to as LTE.

[0024] Figure 1 An example wireless communication network 100 is illustrated in which aspects of the present disclosure may be practiced.For example, the techniques presented herein may be used to help define narrowband areas for enhanced machine type communications (eMTC) performed by wireless devices.

[0025] The network 100 may be an LTE network or some other wireless network. The wireless network 100 may include several evolved Node Bs (eNBs) 110 and other network entities. An eNB is an entity that communicates with a user equipment (UE) and may also be referred to as a base station, a Node B, an access point, etc. Each eNB may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" may refer to a coverage area of ​​an eNB and / or an eNB subsystem serving the coverage area, depending on the context in which the term is used.

[0026] An eNB may provide communication coverage for macro cells, pico cells, femto cells, and / or other types of cells. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a residence) and may allow restricted access by UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG)). An eNB for a macro cell may be referred to as a macro eNB. An eNB for a pico cell may be referred to as a pico eNB. An eNB for a femto cell may be referred to as a femto eNB or a home eNB (HeNB). In Figure 1 In the example shown in , eNB 110a may be a macro eNB for macro cell 102a, eNB 110b may be a pico eNB for pico cell 102b, and eNB 110c may be a femto eNB for femto cell 102c. An eNB may support one or more (e.g., three) cells. The terms "eNB," "base station," and "cell" may be used interchangeably herein.

[0027] The wireless network 100 may also include a relay station. A relay station is an entity that can receive transmissions of data from an upstream station (e.g., an eNB or UE) and send transmissions of the data to a downstream station (e.g., a UE or eNB). A relay station may also be a UE that can relay transmissions for other UEs. Figure 1 In the example shown in FIG. 1 , a relay station 110 d may communicate with macro eNB 110 a and UE 120 d to facilitate communication between eNB 110 a and UE 120 d. A relay station may also be referred to as a relay eNB, a relay base station, a relay, etc.

[0028] The wireless network 100 may be a heterogeneous network including different types of eNBs, such as macro eNBs, pico eNBs, femto eNBs, relay eNBs, etc. These different types of eNBs may have different transmit power levels, different coverage areas, and different effects on interference in the wireless network 100. For example, a macro eNB may have a high transmit power level (e.g., 5 to 40 Watts), while a pico eNB, a femto eNB, and a relay eNB may have a lower transmit power level (e.g., 0.1 to 2 Watts).

[0029] A network controller 130 may be coupled to a set of eNBs and may provide coordination and control for these eNBs. The network controller 130 may communicate with each eNB via a backhaul. The eNBs may also communicate with each other, for example, directly or indirectly via a wireless or wired backhaul.

[0030] UE 120 (e.g., 120a, 120b, 120c) may be dispersed throughout the wireless network 100, and each UE may be stationary or mobile. UE may also be referred to as an access terminal, terminal, mobile station, subscriber unit, station, etc. Some examples of UE may include cellular phones, smart phones, personal digital assistants (PDAs), wireless modems, handheld devices, tablet devices, laptop computers, netbooks, smartbooks, ultrabooks, entertainment devices (e.g., gaming devices, music players), navigation devices, cameras, wearable devices (e.g., smart watches, smart clothing, smart glasses, smart goggles, head-up display devices, smart wristbands, smart jewelry (e.g., smart rings, smart necklaces)), medical devices, health care devices, vehicle-mounted devices, etc. MTC UEs may include sensors, meters, monitors, security devices, location tags, robots / robotic devices, drones, etc. Some MTC UEs and other UEs may be implemented as Internet of Things (IoT) devices (e.g., narrowband IoT (NB-IoT)) or Internet of Everything (IoE) devices. In Figure 1 In FIG. 1 , a solid line with double arrows indicates desired transmissions between a UE and a serving eNB, which is an eNB designated to serve the UE on the downlink and / or uplink. A dashed line with double arrows indicates potentially interfering transmissions between a UE and an eNB.

[0031] Figure 2 It shows that it can be Figure 1 A block diagram of a design of a base station / eNB 110 and a UE 120 for one of the base stations / eNBs and one of the UEs in the network.

[0032] The base station 110 may be equipped with T antennas 234a through 234t, and the UE 120 may be equipped with R antennas 252a through 252r, where in general T≧1 and R≧1.

[0033] At the base station 110, the transmit processor 220 may receive data for one or more UEs from the data source 212, select one or more modulation and coding schemes (MCS) for each UE based on the CQI received from the UE, process (e.g., encode and modulate) the data for the UE based on the MCS selected for each UE, and provide data symbols to all UEs. The transmit processor 220 may also process system information (e.g., for SRPI, etc.) and control information (e.g., CQI requests, grants, upper layer signaling, etc.), and provide overhead symbols and control symbols. The processor 220 may also generate reference symbols for reference signals (e.g., CRS) and synchronization signals (e.g., PSS and SSS). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, overhead symbols, and / or reference symbols where applicable, and may provide T output symbol streams to T modulators (MOD) 232a to 232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232a through 232t may be transmitted via T antennas 234a through 234t, respectively.

[0034] At UE 120, antennas 252a to 252r may receive downlink signals from base station 110 and / or other base stations and may provide received signals to demodulators (DEMOD) 254a to 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) its received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a to 254r, perform MIMO detection on the received symbols where applicable, and provide detected symbols. A receive (RX) processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller / processor 280. A channel processor may determine RSRP, RSSI, RSRQ, CQI, etc.

[0035] On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information from a controller / processor 280 (e.g., for reports including RSRP, RSSI, RSRQ, CQI, etc.). The processor 264 may also generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266, where applicable, further processed by modulators 254a through 254r (e.g., for SC-FDM, OFDM, etc.), and transmitted to the base station 110. At the base station 110, uplink signals from the UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by MIMO detectors 236, where applicable, and further processed by receive processors 238 to obtain decoded data and control information sent by the UE 120. The processor 238 may provide decoded data to a data sink 239 and decoded control information to the controller / processor 240. The base station 110 may include a communication unit 244 and communicate with the network controller 130 via the communication unit 244. The network controller 130 may include a communication unit 294, a controller / processor 290, and a memory 292.

[0036] The controllers / processors 240 and 280 may direct the operations at the base station 110 and the UE 120, respectively, to perform the techniques presented herein for defining a narrowband area for enhanced machine type communication (eMTC) for communication between a UE (e.g., an eMTC UE) and a base station (e.g., an eNodeB). For example, the controller / processor 240 and / or other controllers, processors, and modules at the base station 110, and the controller / processor 280 and / or other controllers, processors, and modules at the UE 120 may perform or direct the operations of the base station 110 and the UE 120, respectively. For example, the controller / processor 240 and / or other controllers, processors, and modules at the base station 110 may perform or direct the operations of the base station 110 and the UE 120, respectively. Figure 6 Operations 600 are shown in FIG. For example, controller / processor 280 and / or other controllers, processors, and modules at UE 120 may perform or direct Figure 6 Operations 600 are shown in FIG. 2. Memories 242 and 282 may store data and program codes for base station 110 and UE 120, respectively. Scheduler 246 may schedule UEs for data transmission on the downlink and / or uplink.

[0037] Figure 3An exemplary frame structure 300 for FDD in LTE is shown. The transmission timeline for each of the downlink and uplink may be divided into units of radio frames. Each radio frame may have a predetermined duration (e.g., 10 milliseconds (ms)) and may be divided into 10 subframes with indices 0 to 9. Each subframe may include two time slots. Each radio frame may thus include 20 time slots with indices 0 to 19. Each time slot may include L symbol periods, e.g., for a normal cyclic prefix (e.g., Figure 3 ) is 7 symbol periods, or 6 symbol periods for an extended cyclic prefix. The 2L symbol periods in each subframe may be assigned indices 0 to 2L-1.

[0038] In LTE, an eNB may transmit a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) on the downlink at the center of the system bandwidth for each cell supported by the eNB. The PSS and SSS may be transmitted in symbol periods 6 and 5, respectively, in subframes 0 and 5 of each radio frame with a normal cyclic prefix, as shown in FIG. Figure 3 As shown in . PSS and SSS can be used by UE for cell search and acquisition. The eNB can transmit a cell-specific reference signal (CRS) across the system bandwidth for each cell supported by the eNB. CRS can be transmitted in certain symbol periods of each subframe and can be used by the UE to perform channel estimation, channel quality measurement, and / or other functions. The eNB can also transmit a physical broadcast channel (PBCH) in symbol periods 0 to 3 in slot 1 of certain radio frames. PBCH can carry some system information. The eNB can transmit other system information in certain subframes, such as a system information block (SIB) on a physical downlink shared channel (PDSCH). The eNB can transmit control information / data on a physical downlink control channel (PDCCH) in the first B symbol periods of a subframe, where B can be configurable for each subframe. The eNB can transmit traffic data and / or other data on the PDSCH in the remaining symbol periods of each subframe.

[0039] Figure 4 Two exemplary subframe formats 410 and 420 with normal cyclic prefixes are shown. Available time-frequency resources can be divided into resource blocks. Each resource block can cover 12 subcarriers in a time slot and can include several resource elements. Each resource element can cover one subcarrier in a symbol period and can be used to send a modulation symbol that can be a real value or a complex value.

[0040] Subframe format 410 may be used for two antennas. CRS may be transmitted from antennas 0 and 1 in symbol periods 0, 4, 7, and 11. A reference signal is a signal known a priori to the transmitter and receiver and may also be referred to as a pilot. CRS is a cell-specific reference signal, for example, generated based on a cell identity (ID). Figure 4 , for a given resource element with label Ra, a modulation symbol may be transmitted from antenna a on the resource element, and no modulation symbol may be transmitted from other antennas on the resource element. Subframe format 420 may be used with four antennas. CRS may be transmitted from antennas 0 and 1 in symbol periods 0, 4, 7, and 11 and from antennas 2 and 3 in symbol periods 1 and 8. For both subframe formats 410 and 420, CRS may be transmitted on uniformly spaced subcarriers, which may be determined based on the cell ID. CRS may be transmitted on the same or different subcarriers depending on its cell ID. For both subframe formats 410 and 420, resource elements not used for CRS may be used to transmit data (e.g., traffic data, control data, and / or other data).

[0041] The PSS, SSS, CRS and PBCH in LTE are described in the publicly available 3GPP TS 36.211 entitled "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation."

[0042] For FDD in LTE, an interleaving structure may be used for each of the downlink and uplink.

[0043] For example, Q interlaces with indices 0 to Q-1 may be defined, where Q may be equal to 4, 6, 8, 10, or some other value. Each interlace may include subframes spaced apart by Q frames. Specifically, interlace q may include subframes q, q+Q, q+2Q, etc., where q∈{0,...,Q-1}.

[0044] The wireless network may support hybrid automatic repeat request (HARQ) for data transmission on the downlink and uplink. For HARQ, a transmitter (e.g., an eNB) may send one or more transmissions of a packet until the packet is correctly decoded by a receiver (e.g., a UE) or some other termination condition is encountered. For synchronous HARQ, all transmissions of the packet may be sent in each subframe of a single interlace. For asynchronous HARQ, each transmission of the packet may be sent in any subframe.

[0045] A UE may be located within the coverage of multiple eNBs. One of these eNBs may be selected to serve the UE. The serving eNB may be selected based on various criteria such as received signal strength, received signal quality, path loss, etc. Received signal quality may be quantified by signal-to-noise-and-interference ratio (SINR), or reference signal received quality (RSRQ), or some other metric. A UE may operate in a strong interference scenario, where the UE may observe severe interference from one or more interfering eNBs.

[0046] Narrowband eMTC

[0047] As mentioned above, the techniques presented herein may be used to help a UE (eg, an eMTC UE) determine narrowband and hopping patterns for use with eMTC.

[0048] The focus of traditional LTE design (e.g., for legacy "non-MTC" devices) is on improving spectral efficiency, ubiquitous coverage, and enhanced Quality of Service (QoS) support. Current LTE system downlink (DL) and uplink (UL) link budgets are designed for coverage of high-end devices (such as state-of-the-art smartphones and tablets) that can support relatively large DL and UL link budgets.

[0049] However, there is also a need to support low-cost, low-rate devices. For example, some standards (e.g., LTE Release 12) have introduced new UEs (referred to as Category 0 UEs) that are generally designed for low-cost or machine-type communications. For machine-type communications (MTC), various requirements may be relaxed because only a limited amount of information may need to be exchanged. For example, relative to legacy UEs, the maximum bandwidth may be reduced, a single receive radio frequency (RF) chain may be used, the peak rate may be reduced (e.g., the transport block size may be a maximum of 100 bits), the transmit power may be reduced, rank 1 transmission may be used, and half-duplex operation may be performed.

[0050] In some cases, if half-duplex operation is performed, the MTC UE may have a relaxed switching time from transmission to reception (or vice versa). For example, the switching time may be relaxed from 20 μs for conventional UEs to 1 ms for MTC UEs. Release 12 MTC UEs may still monitor downlink (DL) control channels in the same manner as conventional UEs, for example, monitoring wideband control channels (e.g., PDCCH) in the first few symbols and narrowband control channels (e.g., ePDCCH) that occupy a relatively narrow band but span the length of a subframe.

[0051] Certain standards (eg, LTE Release 13) may introduce support for various additional MTC enhancements, referred to herein as enhanced MTC (or eMTC). For example, eMTC may provide up to 15 dB of coverage enhancement to MTC UEs.

[0052] like Figure 5 As illustrated in the subframe structure 500 of , an eMTC UE may support narrowband operation while operating in a wider system bandwidth (eg, 1.4 / 3 / 5 / 10 / 15 / 20 MHz). Figure 5 In the example illustrated in , the conventional legacy control region 510 may span the system bandwidth of the first few symbols, while the narrowband region 530 occupies a portion of the system bandwidth of the larger region 520. In some cases, the MTC UE monitoring the narrowband region may operate at 1.4 MHz or 6 resource blocks (RBs).

[0053] As mentioned above, an eMTC UE may be able to operate in a cellular cell with a bandwidth greater than 6 RBs. Within this larger bandwidth, each eMTC UE may still operate (e.g., monitor / receive / transmit) while complying with the 6 physical resource block (PRB) constraint. In some cases, different eMTC UEs may be served by different narrowband regions within the system bandwidth (e.g., each narrowband region spans 6 PRB blocks). Since the system bandwidth may span from 1.4 MHz to 20 MHz, or from 6 RBs to 100 RBs, multiple narrowband regions may exist within a larger bandwidth. The eMTC UE may also switch or hop between multiple narrowband regions to reduce interference.

[0054] Although the sizes of the DL and UL narrowband areas are defined, the locations of available narrowband and hopping patterns for eMTC UEs within the larger bandwidth are not fixed and may need to be defined.

[0055] Because bandwidth is a limited resource, narrowband regions should not be defined so that all or almost all RBs are grouped into narrowband regions with as few empty RBs as possible. In some systems, the number of PRBs in a given bandwidth is not a multiple of six. A narrowband region with 6 RBs operates at 1.4 MHz, and the system bandwidth can be 1.4, 3, 5, 10, 15, and 20 MHz corresponding to 6, 15, 25, 50, 75, and 100 RBs, only one of which is a multiple of 6. For example, a 5 MHz bandwidth cell has 15 available PRBs, which is equal to 2.5 narrowband regions. Thus, for many LTE bandwidths, the system bandwidth cannot be evenly split into narrowband regions. It may be advantageous to define narrowband regions such as to minimize the number of RBs that are not grouped into narrowband regions.

[0056] Narrowband Definition for eMTC

[0057] Figure 6 6 is a flow chart illustrating example operations 600 of wireless communication by a wireless device in accordance with certain aspects of the present disclosure. The wireless device may be, for example, an eNB to communicate with a UE over a narrowband region or a UE to communicate with an eNB over a narrowband region. At 602, operations may begin by identifying one or more narrowband regions within a wider system bandwidth based on an amount of available resources in the system bandwidth. At 604, operations include communicating using at least one of the identified narrowband regions.

[0058] Figure 7 An example resource block configuration 700 for eMTC operation according to certain aspects of the present disclosure is illustrated. In some systems, the center 6 RBs may be used for PSS / SSS and / or paging. For bandwidths with an odd number of RBs (e.g., 1.4 MHz, 3 MHz, 5 MHz, etc.), the center 6 RBs may not be aligned with a physical resource block. For example, Figure 7 As shown in FIG. 7 , the center 6 RBs 702 of the 3 MHz bandwidth are resource blocks 5-9 and half of resource block 4 and half of resource block 10. With the narrowband region defined in the center 6 RBs, an eMTC tuned to the narrowband region for synchronization purposes will not need to re-tune to receive paging transmissions, potentially resulting in energy savings.

[0059] Fig. 8AAn example narrowband region definition 800A according to certain aspects of the present disclosure is illustrated. According to certain aspects, a narrowband region 802A may be defined based on the 6 RBs in the center. In the case where the number of available RBs is not an even number and the 6 RBs in the center are not aligned with the broadband RB boundary, the narrowband region 802A may also not be aligned with the broadband RB boundary. For example, a narrowband (NB) region 802A may be defined as extending from RB 4.5 to RB 10.5. Alternatively, the 6 RB region in the center may be rounded up by 1 RB to 7 RBs. Broadband and eMTC devices may continue to monitor the 6 RBs in the center for paging, and may also extend the region up or down by 0.5 RBs in the 6 RBs in the center, for example, from RB 4 to RB 11. This allows the NB region 802A to be aligned with the broadband RB boundary. A group of 6 RBs from the broadband edge may then be defined as a narrowband region (in this case, NB region 804A and NB region 806A) until the entire broadband bandwidth is divided into narrowband regions. In the case where the total wideband bandwidth cannot be evenly divided into 6 RB regions, overlap will occur between these narrowband regions. For example, here, both NB region 804A and NB region 806A will overlap with NB region 802A. This results in the total number of narrowband regions being equal to the number of resource blocks divided by 6, rounded up, or ceil(nRB / 6).

[0060] In some cases, it may be desirable to have non-overlapping narrowband regions. As mentioned above, in the case where the total number of RBs is not a multiple of six, it is not possible to divide the total number of RBs into narrowband regions of fixed size so that each wideband RB is used. However, using a narrowband region of smaller size in conjunction with a narrowband region of 6 RBs will allow each wideband RB to be used. For example, in the case where the center 6 RBs have been rounded up to 7 to align with the wideband RB boundaries, narrowband regions can be selected in groups of 6 RBs from each edge inward.

[0061] Figure 8B 800B illustrates an example narrowband region definition in accordance with certain aspects of the present disclosure. Figure 8B As illustrated in , the narrowband regions directly adjacent to NB region 802B (rather than overlapping NB region 802B) are reduced in size. As illustrated here, NB region 804B and NB region 806B are 4 RBs instead of 6 RBs. Such an arrangement would place the smaller narrowband regions immediately adjacent to NB region 802B. Alternatively, NB regions may be selected in groups of 6 RBs outward from NB region 802B. Such an arrangement would place the smaller narrowband regions immediately adjacent to the edge of the wideband bandwidth. As illustrated in Figure 8CAs seen in the example narrowband region definition 800C where the central 6 RBs have not been rounded up, half RBs to either side of the NB region 802C may leave the narrowband region unassigned 804C. This only applies to wideband bandwidths with an odd number of RBs, for example.

[0062] In some systems, the narrowband mapping may be different for uplink and downlink. For example, on the downlink, some systems use the center 6 RBs for PSS / SSS / PBCH and / or paging. However, there may be no such requirement on the uplink. For simplicity, the downlink narrowband region may be aligned based on the center 6 RBs. Alternatively, the uplink narrowband region may also be defined so that there is a smaller narrowband region reserved for PUCCH along the edge of the broadband bandwidth.

[0063] Figures 9A-9C Example narrowband region definitions 900A-900C are illustrated, respectively, in accordance with certain aspects of the present disclosure. In some cases, a smaller narrowband region may be defined such that the total number of resource blocks divided by 6 (e.g., mod(nRB,6)) is allocated at the bandwidth edges of the smaller narrowband region. These RBs may be allocated equally between the edges such that the individual size of the smaller RBs is equal to, for example, (mod(nRB,6)) / 2. A narrowband region with 6 RBs may then be allocated between these edges. For example, for Fig.9A For a wideband bandwidth of 3 MHz and 15 RBs in FIG. 6 , mod (15, 6) yields 3 RBs, which are split into two 1.5 RB narrowband regions, NB region 902A and NB region 904A, along the edges of the wideband bandwidth. The remaining RBs between these edges can then be equally allocated into narrowband regions of 6 RBs, as shown in NB region 906A and NB region 908A. However, equally dividing the RBs into narrowband regions along these edges can result in fractional RB allocations (as in NB region 902A and NB region 904A), as well as narrowband regions that may not align with the wideband RBs (such as NB region 906A and NB region 908A in RB 7).

[0064] The distribution of RBs into narrowband regions may be asymmetric if the alignment of the center 6 RBs is not maintained. This asymmetric distribution may allow narrowband regions to be aligned with wideband RBs in the presence of an odd number of wideband RBs. For example, Fig. 9BAs explained in FIG. 1 , in the case where the individual sizes of the smaller RBs (as determined by (mod(nRB,6)) / 2) result in a non-integer, one of the smaller narrowband regions may be rounded down (NB region 902B) (here one RB), and the other smaller narrowband region may be rounded up (NB region 904B) (here two RBs). This rounding allows each narrowband edge to be aligned with each broadband RB edge. Other narrowband regions (such as NB region 906B and NB region 908B) may also be adjusted to be aligned with the broadband RB edge.

[0065] Alternatively, in addition to rounding up the size of one smaller narrowband region and rounding down the size of the other smaller narrowband region, the sizes of both smaller narrowband regions may be rounded down. Fig. 9C As illustrated in FIG. 1 , both NB region 902C and NB region 904C are each rounded down to 1 RB. Additional narrowband regions between these edges may then be defined, for example, NB region 906C and NB region 908C. The remaining RBs in the center RB may then be defined as additional smaller narrowband regions NB region 910C, so that smaller narrowband regions are defined at both the edge and the center of the wideband bandwidth.

[0066] Narrowband frequency hopping for eMTC

[0067] LTE includes hopping between frequencies in a specific pattern to improve transmit diversity. This hopping pattern may be explicitly signaled to the eMTC device in the scheduling grant. For the eMTC device, the additional power usage for monitoring signaling may outweigh the flexibility provided by explicit signaling. According to certain aspects, signaling may be simplified by basing the hopping pattern on the initial narrowband region used for communication. This hopping may be performed within a pair of narrowband regions, or based on a fixed pattern.

[0068] As an example, for a 10MHz bandwidth with 9 narrowband regions numbered from 0 to 8, four groups of narrowband pairs can be defined. For example, these narrowband pairs can be {0,5}, {1,6}, {2,7}, and {3,8}. The jumping behavior can be defined so that the jump can be performed from one member of the narrowband pair to another member of the narrowband pair. Subsequently, the specific jumping behavior is based on the narrowband region initially identified for communication. That is, in the case where a specific wireless device receives an indication that narrowband region 0 is to be initially used for communication, the wireless device will know that it will jump to narrowband region 5 for the next communication without any other additional signaling. This initial indication can be derived from SIB, MIB, or other types of signaling. Additionally, the jump can be performed based on a pattern rather than a mutual jump. In such an implementation, the initial forward jump of five narrowband regions from 0 to 5 can be followed by a backward jump of four narrowband regions from 5 to 1, for example. In either case, the hopping pattern (e.g., for a given bundle size) is predetermined based on the initially identified narrowband region (e.g., fixed by specification or SIB1 / other signaling), and no specific pattern needs to be signaled in a downlink grant or uplink grant. Additionally, specific patterns and pairings may be defined for each system bandwidth (e.g., 3, 5, 10, 15, and 20 Hz).

[0069] In some systems, the frequency hopping pattern may be further defined such that, for example, the initially identified narrowband region for the downlink is associated with the narrowband region hopping for the uplink, and vice versa. For example, again for the 10 Hz bandwidth, in the event that a particular wireless device receives an indication that narrowband region 0 is to be initially used for the downlink, the wireless device will know to next hop to the associated uplink narrowband region 5 for sending a response. Similarly, receiving a DL grant on a particular narrowband region may indicate to the wireless device that it is to hop to the associated downlink narrowband region to receive a downlink transmission. Similarly, a UL grant on a particular narrowband region may indicate to the wireless device that it is to hop to the associated uplink narrowband region for transmission. Similarly, a random access uplink transmission on a particular narrowband region may indicate to the wireless device that it is to hop to the associated downlink narrowband region to receive a random access response.

[0070] As used herein, a phrase referring to "at least one" of a list of items refers to any combination of those items, including single members. As an example, "at least one of a, b, or c" is intended to cover: a, b, c, ab, ac, bc, and abc, as well as any combination with multiple identical elements (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other ordering of a, b, and c).

[0071] As used herein, the term "identifying" encompasses a wide variety of actions. For example, "identifying" may include calculating, computing, processing, deriving, investigating, searching (e.g., searching in a table, database, or other data structure), ascertaining, and the like. Also, "identifying" may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), and the like. Also, "identifying" may include resolving, selecting, choosing, establishing, and the like.

[0072] In some cases, rather than actually communicating frames, a device may have an interface for communicating frames for transmission or reception. For example, a processor may output frames to an RF front end via a bus interface for transmission. Similarly, rather than actually receiving frames, a device may have an interface for obtaining frames received from another device. For example, a processor may obtain (or receive) frames for transmission from an RF front end via a bus interface.

[0073] The methods disclosed herein include one or more steps or actions for achieving the described methods. These method steps and / or actions may be interchangeable with each other without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions may be changed without departing from the scope of the claims.

[0074] The various operations of the methods described above may be performed by any suitable device capable of performing the corresponding functions. These devices may include various hardware and / or software components and / or modules, including but not limited to circuits, application specific integrated circuits (ASICs), or processors. Software should be broadly interpreted to mean instructions, data, code, or any combination thereof, whether referred to as software, firmware, middleware, code, microcode, hardware description language, machine language, or other. In general, where there are operations illustrated in the accompanying drawings, these operations may have corresponding paired device plus functional components.

[0075] The various operations of the methods described above may be performed by any suitable device capable of performing the corresponding functions. These devices may include various hardware and / or software components and / or modules, including but not limited to circuits, application specific integrated circuits (ASICs), or processors. In general, where operations are illustrated in the accompanying drawings, those operations may be performed by any suitable corresponding paired device plus functional components.

[0076] For example, means for identifying and / or means for communicating may include one or more processors or other components (such as Figure 2 The transmit processor 220, controller / processor 240, receive processor 238, and / or antenna(s) 234 of the base station 110 illustrated in FIG. 1 , or Figure 2 264, controller / processor 280, receive processor 258, and / or antenna(s) 252 of the user terminal 120 as illustrated in FIG.

[0077] Those skilled in the art will appreciate that information and signals 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 referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or a combination thereof.

[0078] The skilled person will further appreciate that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the disclosure herein may be implemented as hardware, software, or a combination thereof. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. The skilled person may implement the described functionality in different ways for each specific application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

[0079] The various illustrative logical blocks, modules, and circuits described in conjunction with the disclosure herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0080] The steps of the method or algorithm described in conjunction with the disclosure herein can be implemented directly in hardware, in a software module executed by a processor, or in a combination thereof. The software module can reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a phase change memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read and write information from / to the storage medium. In an alternative, a storage medium can be integrated into a processor. The processor and the storage medium can reside in an ASIC. The ASIC can reside in a user terminal. In an alternative, the processor and the storage medium can reside in a user terminal as discrete components.

[0081] In one or more exemplary designs, the functions described can be implemented in hardware, software, or a combination thereof. If implemented in software, each function can be stored on or transmitted by a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, including any media that facilitates the transfer of a computer program from one place to another. Storage media can be any available media that can be accessed by a general or special-purpose computer. As an example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD / DVD or other optical disk storage, disk storage or other magnetic storage devices, or any other medium that can be used to carry or store the desired program code means in the form of instructions or data structures and can be accessed by a general or special-purpose computer, or a general or special-purpose processor. Any connection is also properly referred to as a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwaves, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the definition of the medium. Disk and disc as used herein include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, wherein disk often reproduces data magnetically while disc reproduces data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0082] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the universal principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Therefore, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication by a user equipment (UE), comprising: determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; receiving an indication of an initial narrowband region within the first one or more narrowband regions; identifying a second one or more narrowband regions within the first one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; and Communications are received or transmitted in the second one or more narrowband regions.

2. The method of claim 1, wherein the communications in the second one or more narrowband regions are bundled.

3. The method of claim 1, wherein the first one or more narrowband regions comprise a downlink narrowband region.

4. The method of claim 3, wherein the communications in the second one or more narrowband regions include physical downlink control channel communications or physical downlink shared channel communications.

5. The method of claim 1, wherein the first one or more narrowband regions include an uplink narrowband region.

6. The method of claim 5, wherein the communications in the second one or more narrowband regions include uplink communications.

7. The method of claim 1, wherein when the total number of RBs in the system bandwidth is an odd number, the first one or more narrowband regions do not include a center resource block (RB) of the system bandwidth.

8. An apparatus for wireless communication, comprising: at least one processor; as well as a memory coupled to the at least one processor, the memory comprising code executable by the at least one processor to cause the apparatus to: determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; receiving an indication of an initial narrowband region within the first one or more narrowband regions; identifying a second one or more narrowband regions within the first one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; and Communications are received or transmitted in the second one or more narrowband regions.

9. The apparatus of claim 8, wherein the communications in the second one or more narrowband regions are bundled.

10. The apparatus of claim 8, wherein the first one or more narrowband regions comprise a downlink narrowband region.

11. The apparatus of claim 10, wherein the communications in the second one or more narrowband regions comprise physical downlink control channel communications or physical downlink shared channel communications.

12. The apparatus of claim 8, wherein the first one or more narrowband regions comprise an uplink narrowband region.

13. The apparatus of claim 12, wherein the communications in the second one or more narrowband regions comprise uplink communications.

14. The apparatus of claim 8, wherein when the total number of RBs in the system bandwidth is an odd number, the first one or more narrowband regions do not include a center resource block (RB) of the system bandwidth.

15. A device for wireless communication, comprising: means for determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; means for receiving an indication of an initial narrowband region within said first one or more narrowband regions; means for identifying, within the first one or more narrowband regions, a second one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; as well as Means for receiving or transmitting communications in the second one or more narrowband regions.

16. A non-transitory computer readable medium for wireless communication, the computer readable medium comprising code executable by at least one processor to cause an apparatus to: determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; receiving an indication of an initial narrowband region within the first one or more narrowband regions; identifying a second one or more narrowband regions within the first one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; and Communications are received or transmitted in the second one or more narrowband regions.

17. A method for wireless communication by a base station, comprising: determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; sending an indication of an initial narrowband region within the first one or more narrowband regions; identifying a second one or more narrowband regions within the first one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; and Communications are sent or received in the second one or more narrowband regions.

18. The method of claim 17, wherein the communications in the second one or more narrowband regions are bundled.

19. The method of claim 17, wherein the first one or more narrowband regions comprise a downlink narrowband region.

20. The method of claim 19, wherein the communications in the second one or more narrowband regions include physical downlink control channel communications or physical downlink shared channel communications.

21. The method of claim 17, wherein the first one or more narrowband regions include an uplink narrowband region.

22. The method of claim 21, wherein the communications in the second one or more narrowband regions include uplink communications.

23. The method of claim 17, wherein when the total number of RBs in the system bandwidth is an odd number, the first one or more narrowband regions do not include a center resource block (RB) of the system bandwidth.

24. An apparatus for wireless communication, comprising: at least one processor; as well as a memory coupled to the at least one processor, the memory comprising code executable by the at least one processor to cause the apparatus to: determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; sending an indication of an initial narrowband region within the first one or more narrowband regions; identifying a second one or more narrowband regions within the first one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; and Communications are sent or received in the second one or more narrowband regions.

25. The apparatus of claim 24, wherein the communications in the second one or more narrowband regions are bundled.

26. The apparatus of claim 24, wherein the first one or more narrowband regions comprise a downlink narrowband region.

27. The apparatus of claim 26, wherein the communications in the second one or more narrowband regions comprise physical downlink control channel communications or physical downlink shared channel communications.

28. The apparatus of claim 24, wherein the first one or more narrowband regions comprise an uplink narrowband region.

29. The apparatus of claim 28, wherein the communications in the second one or more narrowband regions comprise uplink communications.

30. The apparatus of claim 24, wherein when the total number of RBs in the system bandwidth is an odd number, the first one or more narrowband regions exclude a center resource block (RB) of the system bandwidth.

31. A device for wireless communication, comprising: means for determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; means for transmitting an indication of an initial narrowband region within said first one or more narrowband regions; means for identifying, within the first one or more narrowband regions, a second one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; as well as Means for transmitting or receiving communications in the second one or more narrowband regions.

32. A non-transitory computer readable medium for wireless communication, the computer readable medium comprising code executable by at least one processor to cause an apparatus to: determining the first one or more narrowband regions based at least in part on whether a total number of resource blocks (RBs) in a system bandwidth is even or odd; sending an indication of an initial narrowband region within the first one or more narrowband regions; identifying a second one or more narrowband regions within the first one or more narrowband regions according to a hopping pattern, wherein each hopping according to the hopping pattern is based at least in part on the indication of the initial narrowband region; and Communications are sent or received in the second one or more narrowband regions.

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