Patent Description:
Research and development continue to advance the UMTS technologies not only to meet the growing demand for mobile broadband access, but to advance and enhance the user experience with mobile communications.

The <NPL>, discusses some issues on PUCCH transmission for Rel-<NUM> MTC, including narrow band PUCCH design and PUCCH resource allocation. Based on the discussion, said draft has the following observations:.

There is still a need for more efficient coverage enhancement and normal mode switching.

The present invention provides a solution as defined in the independent claims.

The foregoing has outlined rather broadly the background in order that the detailed description that follows may be better understood. Features and advantages of the invention will be described hereinafter.

This disclosure relates generally to providing or participating in authorized shared access between two or more wireless communications systems, also referred to as wireless communications networks. In various embodiments, the techniques and apparatus may be used for wireless communication networks such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single-carrier FDMA (SC-FDMA) networks, LTE networks, GSM networks, as well as other communications networks. As described herein, the terms "networks" and "systems" may be used interchangeably.

The present disclosure is concerned with the evolution of wireless technologies from LTE, <NUM>, <NUM>, and beyond with shared access to wireless spectrum between networks using a collection of new and different radio access technologies or radio air interfaces.

In particular, <NUM> networks contemplate diverse deployments, diverse spectrum, and diverse services and devices that may be implemented using an OFDM-based unified, air interface. In order to achieve these goals, further enhancements to LTE and LTE-A are considered in addition to development of a new radio (NR) technology. The <NUM> NR will be capable of scaling to provide coverage (<NUM>) to a massive Internet of things (IoTs) with an ultra-high density (e.g., ~<NUM> nodes/km<NUM>), ultra-low complexity (e.g., ~<NUM> of bits/sec), ultra-low energy (e.g., ~<NUM>+ years of battery life), and deep coverage with the capability to reach challenging locations; (<NUM>) including mission-critical control with strong security to safeguard sensitive personal, financial, or classified information, ultra-high reliability (e.g., -<NUM>% reliability), ultra-low latency (e.g., - <NUM>), and users with wide ranges of mobility or lack thereof; and (<NUM>) with enhanced mobile broadband including extreme high capacity (e.g., - <NUM> Tbps/km<NUM>), extreme data rates (e.g., multi-Gbps rate, <NUM>+ Mbps user experienced rates), and deep awareness with advanced discovery and optimizations.

The <NUM> NR may be implemented to use optimized OFDM-based waveforms with scalable numerology and transmission time interval (TTI); having a common, flexible framework to efficiently multiplex services and features with a dynamic, low-latency time division duplex (TDD)/frequency division duplex (FDD) design; and with advanced wireless technologies, such as massive multiple input, multiple output (MIMO), robust millimeter wave (mmWave) transmissions, advanced channel coding, and device-centric mobility. Scalability of the numerology in <NUM> NR, with scaling of subcarrier spacing, may efficiently address operating diverse services across diverse spectrum and diverse deployments. For example, in various outdoor and macro coverage deployments of less than <NUM> FDD/TDD implementations, subcarrier spacing may occur with <NUM>, for example over <NUM>, <NUM>, <NUM>, <NUM>, and the like bandwidth. For other various outdoor and small cell coverage deployments of TDD greater than <NUM>, subcarrier spacing may occur with <NUM> over <NUM>/<NUM> bandwidth. For other various indoor wideband implementations, using a TDD over the unlicensed portion of the <NUM> band, the subcarrier spacing may occur with <NUM> over a <NUM> bandwidth. Finally, for various deployments transmitting with mmWave components at a TDD of <NUM>, subcarrier spacing may occur with <NUM> over a <NUM> bandwidth.

<FIG> is a block diagram illustrating <NUM> network <NUM> including various base stations and UEs configured according to aspects of the present disclosure. The <NUM> network <NUM> includes a number of base stations <NUM> and other network entities. A base station may be a station that communicates with the UEs and may also be referred to as a base station, an access point, and the like. Each base station <NUM> may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" can refer to this particular geographic coverage area of a base station and/or a base station subsystem serving the coverage area, depending on the context in which the term is used.

A base station may provide communication coverage for a macro cell or a small cell, such as a pico cell or a femto cell, and/or other types of cell. A base station for a macro cell may be referred to as a macro base station. A base station for a small cell may be referred to as a small cell base station, a pico base station, a femto base station or a home base station. In the example shown in <FIG>, the base stations 105d and 105e are regular macro base stations, while base stations 105a-105c are macro base stations enabled with one of <NUM> dimension (3D), full dimension (FD), or massive MIMO. Base stations 105a-105c take advantage of their higher dimension MIMO capabilities to exploit 3D beamforming in both elevation and azimuth beamforming to increase coverage and capacity. Base station 105f is a small cell base station which may be a home node or portable access point. A base station may support one or multiple (e.g., two, three, four, and the like) cells.

The <NUM> network <NUM> may support synchronous or asynchronous operation.

The UEs <NUM> are dispersed throughout the wireless network <NUM>, and each UE may be stationary or mobile. A UE may also be referred to as a terminal, a mobile station, a subscriber unit, a station, or the like. A UE may be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a wireless local loop (WLL) station, or the like. UEs 115a-115d are examples of mobile smart phone-type devices accessing <NUM> network <NUM>. A UE may also be a machine specifically configured for connected communication, including machine type communication (MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT) and the like. UEs 115e-<NUM> are examples of various machines configured for communication that access <NUM> network <NUM>. A UE may be able to communicate with any type of the base stations, whether macro base station, small cell, or the like. In <FIG>, a lightning bolt (e.g., communication links) indicates wireless transmissions between a UE and a serving base station, which is a base station designated to serve the UE on the downlink and/or uplink, or desired transmission between base stations, and backhaul transmissions between base stations.

In operation at <NUM> network <NUM>, base stations 105a-105c serve UEs 115a and 115b using 3D beamforming and coordinated spatial techniques, such as coordinated multipoint (CoMP) or multi-connectivity. Macro base station 105d performs backhaul communications with base stations 105a-105c, as well as small cell, base station 105f. Macro base station 105d also transmits multicast services which are subscribed to and received by UEs 115c and 115d.

<NUM> network <NUM> also support mission critical communications with ultra-reliable and redundant links for mission critical devices, such UE 115e, which is a drone. Redundant communication links with UE 115e include from macro base stations 105d and 105e, as well as small cell base station 105f. Other machine type devices, such as UE 115f (thermometer), UE <NUM> (smart meter), and UE <NUM> (wearable device) may communicate through <NUM> network <NUM> either directly with base stations, such as small cell base station 105f, and macro base station 105e, or in multi-hop configurations by communicating with another user device which relays its information to the network, such as UE 115f communicating temperature measurement information to the smart meter, UE <NUM>, which is then reported to the network through small cell base station 105f. <NUM> network <NUM> may also provide additional network efficiency through dynamic, low-latency TDD/FDD communications, such as in a vehicle-to-vehicle (V2V) mesh network between UEs 115i-<NUM> communicating with macro base station 105e.

<FIG> shows a block diagram of a design of a base station <NUM> and a UE <NUM>, which may be one of the base stations and one of the UEs in <FIG>. At the base station <NUM>, a transmit processor <NUM> may receive data from a data source <NUM> and control information from a controller/processor <NUM>. The control information may be for the PBCH, PCFICH, PHICH, PDCCH, EPDCCH, MPDCCH etc. The data may be for the PDSCH, etc. The transmit processor <NUM> may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The transmit processor <NUM> may also generate reference symbols, e.g., for the PSS, SSS, and cell-specific reference signal. A transmit (TX) multiple-input multiple-output (MIMO) processor <NUM> may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) 232a through 232t. Downlink signals from modulators 232a through 232t may be transmitted via the antennas 234a through 234t, respectively.

At the UE <NUM>, the antennas 252a through 252r may receive the downlink signals from the base station <NUM> and may provide received signals to the demodulators (DEMODs) 254a through 254r, respectively. A MIMO detector <NUM> may obtain received symbols from all the demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols.

On the uplink, at the UE <NUM>, a transmit processor <NUM> may receive and process data (e.g., for the PUSCH) from a data source <NUM> and control information (e.g., for the PUCCH) from the controller/processor <NUM>. The symbols from the transmit processor <NUM> may be precoded by a TX MIMO processor <NUM> if applicable, further processed by the modulators 254a through 254r (e.g., for SC-FDM, etc.), and transmitted to the base station <NUM>. At the base station <NUM>, the uplink signals from the UE <NUM> may be received by the antennas <NUM>, processed by the demodulators <NUM>, detected by a MIMO detector <NUM> if applicable, and further processed by a receive processor <NUM> to obtain decoded data and control information sent by the UE <NUM>. The processor <NUM> may provide the decoded data to a data sink <NUM> and the decoded control information to the controller/processor <NUM>.

The controller/processor <NUM> and/or other processors and modules at the base station <NUM> may perform or direct the execution of various processes for the techniques described herein. The controllers/processor <NUM> and/or other processors and modules at the UE <NUM> may also perform or direct the execution of the functional blocks illustrated in <FIG>-<NUM>, and/or other processes for the techniques described herein. The memories <NUM> and <NUM> may store data and program codes for the base station <NUM> and the UE <NUM>, respectively.

With the trends towards universal connectivity and the increase of more machines and devices having wireless capabilities for reporting data or other low level communications, 3GPP have proposed new access technologies to accommodate more machine-type communications in the enhanced machine-type communication (eMTC) and narrow band Internet of things (NB-IoT) standards in Rels. <NUM> and <NUM>. Considering the context for these technologies, the devices specifically designed for this type of communication may be lower cost, lower complexity devices, that may be positioned in remote and inhospitable places, thus, increasing the need for longer battery life and the ability to provide some communication coverage in very low signal-to-noise ratio (SNR) environments. At the same time, these devices may not need to perform some of the more advance features of modem smart phones.

Accordingly, the standards proposed for access technologies, such as eMTC and NB-IoT, provide for increased power management to improve power consumption and, therefore, battery life, while using lower cost components. Narrowing the operational bandwidth allows for the lower cost components to facilitate communications in such low SNR environments while still allowing deployment in any LTE spectrum and coexistence with other LTE services within the same bandwidths. As currently suggested, eMTC operates with enhanced coverage within a <NUM> bandwidth, while NB-IoT operates with enhanced coverage within an even smaller <NUM> bandwidth, as compared with LTE's normal mode, which also supports larger operational bandwidths, such as <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. While normal mode LTE networks may support some similar operational bandwidths, e.g., <NUM>, it does not support normal mode operations at the same lower SNRs that eMTC and NB-IoT offer in their extended coverage abilities.

While eMTC and NB-IoT were proposed to accommodate communications from lower-cost and lower-complexity devices, regular LTE UEs may also be configured to take advantage of the additional technologies in order to extend the coverage of existing LTE communications. As such, regular LTE UEs may include both a normal mode, which operates using the typical coverage provided by the standard LTE procedures (e.g., using PDCCH/PDSCH), and a coverage extension (CE) mode, which provides extended coverage according to the more MTC-style procedures (e.g., using NPDCCH/NPDSCH or MPDCCH/MPDSCH, which have lower code rate/repetitions).

In idle mode, such a UE may switch between CE mode and non-CE mode based on its channel quality measurements. However, the network may not be aware of which mode the UE is in. This may cause problems when the network sends pages for the UE. When in the normal mode, the network will send UE pages via the PDCCH, which the idle mode UE will be monitoring, while in CE mode, the network would send UE pages in a narrowband-PDCCH (NPDCCH). If the network does not know which mode the UE currently resides, it may send pages in a PDCCH that the UE is not monitoring, which may cause a delay in communications. Various aspects of the present disclosure are directed to accommodating UEs in either normal mode or CE mode without incurring unnecessary communication delays.

<FIG> is a block diagram illustrating base stations 105c and 105e and UEs 115a-115d, all configured according to various aspects of the present disclosure. UEs 115a-115d may switch between various coverage modes depending on the communication conditions experienced at the UEs. In one example aspect, UEs 115a-115d make the network aware of the particular mode the UE is in. In such aspect, a new RRC connection may be established in which UEs 115a-115c send "dummy" non-access stratum (NAS) messages that inform mobility management (MM) function entities <NUM> and <NUM>, respectively, through the serving base station, base stations 105c and 105e, of the change in coverage. MM function entities <NUM> and <NUM> may include various nodes or functionalities exercised by various nodes. For example, in LTE operations, MM function entities <NUM> and <NUM> may include mobility management entities (MMEs), while in <NUM> NR operations, the mobility management functions includes network nodes or entities that provide the access and mobility management function (AMF) with both the security context management function (SCMF) and secure anchor function (SEAF). Alternatively, instead of transmitting a NAS message, UE 115a-d may transmit an RRC message to base stations 105c and 105e, respectively, indicating the new coverage mode, and base station 105c and 105e would generate the NAS message to MM function entities <NUM> and <NUM>, respectively.

<FIG> is a block diagram illustrating base station <NUM> configured according to one aspect of the present disclosure. Base station <NUM> includes the structure, hardware, and components as illustrated for base station <NUM> of <FIG>. For example, base station <NUM> includes controller/processor <NUM>, which operates to execute logic or computer instructions stored in memory <NUM>, as well as controlling the components of base station <NUM> that provide the features and functionality of base station <NUM>. Base station <NUM>, under control of controller/processor <NUM>, transmits and receives signals via wireless radios 1100a-t and antennas 234a-t. Wireless radios 1100a-t include various components and hardware, as illustrated in <FIG> for base station <NUM>, including modulator/demodulators 232a-t, MIMO detector <NUM>, receive processor <NUM>, transmit processor <NUM>, and TX MIMO processor <NUM>. <FIG> is a block diagram illustrating UE <NUM> configured according to one aspect of the present disclosure. UE <NUM> includes the structure, hardware, and components as illustrated for UE <NUM> of <FIG>. For example, UE <NUM> includes controller/processor <NUM>, which operates to execute logic or computer instructions stored in memory <NUM>, as well as controlling the components of UE <NUM> that provide the features and functionality of UE <NUM>. UE <NUM>, under control of controller/processor <NUM>, transmits and receives signals via wireless radios 1200a-r and antennas 252a-r. Wireless radios 1200a-r include various components and hardware, as illustrated in <FIG> for base station <NUM>, including modulator/demodulators 254a-r, MIMO detector <NUM>, receive processor <NUM>, transmit processor <NUM>, and TX MIMO processor <NUM>.

The extended coverage enhancements introduced in the machine-type standards are currently defined for narrowband operation. Thus, the UE/base station operating in a coverage enhancement mode would rely on narrowband communications. In the case of NB-IoT, these narrowband channels span <NUM> only. Accordingly, in order for a UE, such as a smartphone to support coverage enhancements, the UE would need to support the specific narrowband. One procedure within NB-IoT used to increase coverage enhancement is to provide repeating uplink and downlink transmissions. Thus, using a repetition factor communicated between the UE and base station, transmissions, such as PDCCH, PDSCH, PUSCH, PUCCH, and the like, are repetitively transmitted according to the repetition factor.

<FIG> is a block diagram illustrating example blocks executed to implement one aspect of the present disclosure that is not claimed. At block <NUM>, a UE detects channel coverage conditions below a selected threshold level. For example, UE <NUM> takes channel measurements and performs measurements of the communication conditions it experiences in its location near base station <NUM>.

At block <NUM>, the UE signals a coverage extension condition to a serving base station in response to the poor channel coverage. For example, UE <NUM> signals base station <NUM> that channel conditions are so poor that a coverage extension condition exists.

At block <NUM>, in response to the signaling the coverage extension condition, the UE receives repeated copies of transmissions from the serving base station, wherein the repeated copies are repeated at a selected repetition factor. In one aspect of the present disclosure, instead of requiring UE <NUM> to switch modes to improve coverage, repetition factors would be increased in the current, normal mode for existing channels in order to experience enhanced coverage in the current normal mode. For example, instead of supporting both ePDCCH for normal coverage and NPDCCH for extended coverage, the modem of UE <NUM> can simply support ePDCCH and repeated ePDCCH. This may simplify the receiver design and reduce receiver cost. The bundled channels subject to the repeated transmissions include one or more of: PDCCH, PDSCH, PUSCH, PUCCH, PRACH, PBCH, PSS, SSS. The repetition factors may be predetermined and communicated in control messages between UE <NUM> and base station <NUM>.

Additional features for the machine type enhanced coverage standards include support of frequency hopping with narrowband frequencies to reduce transmission congestion. In order to support frequency hopping with narrowband frequencies, current NB-IoT or eMTC devices would typically perform frequency retuning. Thus, a gap is generally introduced between frequency hops to allow for the device to tune to the new frequency. However, more advanced UEs (e.g., non-machine-type devices) may have capabilities for baseband processing that support wideband frequencies. Accordingly, additional aspects of the present disclosure provide for regular UEs to define the same narrowband frequency hopping signaling across the wideband bandwidth capabilities of the UE. Therefore, such UEs may transmit at the narrowband frequency hops without inserting a retuning gap. Thus, depending on the UE capability, different groups of UEs may perform the narrowband frequency hopping differently. Less capable, machine-type UEs transmit with retuning gaps, while other, more capable UEs transmit without retuning gaps.

<FIG> is a block diagram illustrating example blocks executed to implement an embodiment of the present disclosure. The example blocks will also be described with respect to UE <NUM>, as illustrated in <FIG>.

At block <NUM>, a UE determine that coverage conditions of the UE support narrowband frequency hopping for transmissions, wherein the narrowband frequency hopping includes uplink transmission of data without a gap between hopped frequencies. For example, UE <NUM>, under control of controller/processor <NUM>, may activate narrowband frequency hopping <NUM>, stored in memory <NUM>. The execution environment of narrowband frequency hopping <NUM> allows UE <NUM> to perform various measurements to determine the channel conditions and connection conditions at its current location, and whether those coverage conditions support narrowband frequency hopping for transmissions. UE <NUM> may be a regular smart phone capable of advanced communication operations in LTE-A.

At block <NUM>, the UE may indicate, in response to the determining, that the UE is configured with capabilities to support the narrowband frequency hopping without a gap. For example, UE <NUM>, under control of controller/processor <NUM>, may indicate that the UE is configured with capabilities to support the narrowband frequency hopping. Additionally, because UE <NUM> is able to handle wideband baseband processing, there is no need to continually retune frequencies for each frequency hopped as each of the hopped frequencies falls within the total wideband bandwidth available to UE <NUM>.

The functional blocks and modules in <FIG>-<NUM> may comprise processors, electronics devices, hardware devices, electronics components, logical circuits, memories, software codes, firmware codes, etc., or any combination thereof.

Claim 1:
A method of wireless communication, comprising:
performing, at a user equipment, UE, (<NUM>), measurements to determine coverage conditions of the UE (<NUM>), including channel conditions and connection conditions at its current location, and to determine whether the coverage conditions of the UE (<NUM>) support narrowband frequency hopping for transmissions;
determining (<NUM>), at the UE (<NUM>), whether the coverage conditions of the UE (<NUM>) support narrowband frequency hopping for transmissions, wherein the narrowband frequency hopping includes uplink transmission of data without a gap between hopped frequencies; and
indicating (<NUM>), by the UE (<NUM>) and in response to the determining that coverage conditions of the UE (<NUM>) support narrowband frequency hopping for transmissions, that the UE (<NUM>) is configured with capabilities to support the narrowband frequency hopping without a gap.