Techniques for transmitting system information

Abstract

Describe a technique for transmitting system information for time-division duplex (TDD) communication in a radio access network (RAN). Regarding the method aspect of this technique, a master information block (MIB) is transmitted on an anchor carrier (602-1) for TDD communication in the RAN. The MIB indicates the spectral resources (602-1; 602-2) of system information blocks (SIBs) allocated for TDD communication in the RAN. The SIBs are transmitted on the spectral resources (602-1; 602-2) indicated in the MIB.

Description

Technical Field

[0001] The present disclosure generally relates to techniques for transmitting and receiving system information. More particularly, methods and apparatuses for transmitting and receiving system information blocks in a radio access network are provided. Background Art

[0002] Radio devices access a radio access network (RAN) by scanning certain radio carriers to obtain system information elements and time synchronization signals necessary for accessing the RAN. Examples of such radio devices include mobile broadband (MBB) devices (such as user equipment (UE) according to the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE)) and narrowband (NB) devices (such as 3GPP NB Internet of Things (NB-IoT) UE). Examples of basic system information include the master information block (MIB) for 3GPP systems. A carrier that facilitates the initial synchronization of NB-IoT UE is referred to as an anchor carrier.

[0003] Similar to existing LTE UE, NB-IoT UE is only required to search for carriers on a 100 kHz carrier raster, that is, NB-IoT UE attempts to search for NB-IoT carriers in steps of 100 kHz. Therefore, the carrier raster for the downlink of the NB-IoT system is on a 100 kHz frequency grid. The 100 kHz grid means that for in-band deployment of the NB-IoT system, the anchor carrier can only be placed in certain physical resource blocks (PRBs) of the LTE system.

[0004] In an NB-IoT system configured for time division duplex (TDD), downlink and uplink transmissions must share the same carrier frequency. The transmission of the primary synchronization signal, secondary synchronization signal, and physical broadcast channel of MIB-NB occupies the downlink, leaving very few downlink subframes on the anchor carrier for other system information broadcasts, paging, and downlink user traffic.

[0005] In addition, the division of downlink and uplink subframes in TDD RAN is defined by the uplink-downlink TDD configuration. For some uplink-centric configurations, such as Configuration 6 in Table 4.2-2 of document 3GPP TS 36.211 (e.g., version 14.4.0), after scheduling the transmission of the synchronization signal and the physical broadcast channel of MIB-NB, there are few downlink subframes left for anything else. One way can avoid such configurations, but at least in some deployments, the coexistence of the MBB system and the NB system in the RAN requires such configurations. For example, an LTE system may require an uplink-downlink TDD configuration that is uplink-centric, and the NB-IoT system may have to use the same uplink-downlink TDD configuration used by the LTE system. Another way can depend on using very different formats of MIB-NB depending on the uplink-downlink TDD configuration, but different formats increase the complexity of the radio device, which is contrary to the slim design of the NB-IoT UE at least in some deployments. Summary of the Invention

[0006] Accordingly, there is a need for a technique for flexibly and efficiently transmitting system information in a time division duplex radio access network. More particularly, there is a need for a technique that allows system information to be transmitted with various uplink-downlink time division duplex configurations. Alternatively or additionally, there is a need for a technique that allows narrowband system information to be transmitted in a unified format in different deployments relative to a mobile broadband system.

[0007] According to one aspect, there is provided a method for transmitting system information for time division duplex (TDD) communication in a radio access network (RAN). The method includes or triggers the following steps: transmitting a master information block (MIB) on an anchor carrier of TDD communication in the RAN. The MIB indicates the spectral resources of system information blocks (SIBs) allocated for TDD communication in the RAN. The method further includes or triggers the following step: transmitting the SIB on the spectral resources indicated in the MIB.

[0008] The method can be implemented as a method for indicating the spectral resources for SIB transmission in TDD communication. The resources and / or functionality for TDD communication (e.g., of the RAN) can be referred to as a TDD system. TDD communication can involve at least one radio device within the coverage of the RAN. Herein, radio device and user equipment (UE) can be used interchangeably.

[0009] Spectrum resources may include non-anchor carriers in addition to anchor carriers. A non-anchor carrier may be a carrier on which a radio device does not assume to transmit a primary synchronization signal, a secondary synchronization signal, and / or a MIB. For example, a non-anchor carrier may be off the carrier grid of the carrier frequency that defines potential anchor carriers. The carrier grid may be compatible with Section 5.7.2 of document 3GPP TS 36.104 (e.g., version 14.5.0).

[0010] This technology can be implemented for narrowband (NB) TDD communication. Resources and / or functionality (e.g., of the RAN) for NB TDD communication may be referred to as an NB TDD system or an NB Internet of Things (NB-IoT) TDD system (or simply: an NB system or an NB-IoT system). In this document, NB and NB-IoT may be used interchangeably. The MIB and SIB for NB TDD communication may be referred to as MIB-NB and SIB-NB (e.g., SIB1-NB), respectively. A radio device involved in or configured for NB TDD communication may be referred to as an NB IoT device.

[0011] This technology can be compatible with different deployments (also referred to as: operation modes) of non-existence or coexistence with respect to mobile broadband (MBB) communication in the RAN. The deployment may include at least one of the deployment of NB communication within the band of MBB communication, the deployment of NB communication in one or more guard bands of MBB communication, and the independent deployment of NB communication that does not rely on MBB communication. The deployment may include those in Section 5.5a of document 3GPP TS 36.300 (e.g., version 14.4.0).

[0012] At least some embodiments of this technology enable the RAN to effectively indicate the spectrum resources (e.g., non-anchor carriers) of the SIB. Several bits in the MIB may indicate the spectrum resources of the SIB. By implementing this technology in an NB-IoT TDD system, the RAN may have reasonable flexibility to transmit the SIB on an anchor carrier or on a non-anchor carrier (e.g., for all three deployments) with a reasonable low signaling overhead and / or design complexity for NB IoT devices.

[0013] One aspect of this technology can be implemented at the RAN. A base station or cell of the RAN may execute this method. A base station may cover any station configured to provide radio access to at least one radio device. Each radio device or radio devices may be a user equipment (UE).

[0014] According to another aspect, a method of receiving system information for time division duplex (TDD) communication in a radio access network (RAN) is provided. The method includes or triggers the following steps: receiving a master information block (MIB) on an anchor carrier for TDD communication in the RAN. The MIB indicates the spectrum resources of system information blocks (SIBs) allocated for TDD communication in the RAN. The method further includes or triggers the following steps: receiving the SIBs on the spectrum resources indicated in the MIB.

[0015] Other aspects of the present technology may include any feature or step disclosed herein in the context of one aspect, or any feature or step corresponding to such disclosure in the context of other aspects.

[0016] Other aspects of the technology may be implemented by a radio device. The radio device may be configured for peer-to-peer communication (e.g., on a sidelink) and / or for accessing the RAN (e.g., uplink (UL) and / or downlink (DL)). The radio device may be a user equipment (UE, e.g., a 3GPP UE) or a mobile or portable station (STA, e.g., a Wi-Fi STA). In particular, the radio device may be an NB-IoT device and / or a device for machine type communication (MTC).

[0017] Regarding a further aspect, a computer program product is provided. The computer program product includes program code portions for performing any of the steps of the method aspects disclosed herein when the computer program product is executed by one or more computing devices. The computer program product may be stored on a computer-readable recording medium. The computer program product may also be provided for downloading via a data network (e.g., via the RAN and / or via the Internet and / or through a base station). Alternatively or additionally, the method may be encoded in a field programmable gate array (FPGA) and / or an application specific integrated circuit (ASIC), or the functionality may be provided for downloading by means of a hardware description language.

[0018] Regarding an apparatus aspect, an apparatus for transmitting system information for time division duplex (TDD) communication in a radio access network (RAN) is provided. The apparatus is configured to perform a method aspect.

[0019] Regarding another apparatus aspect, an apparatus for receiving system information for time division duplex (TDD) communication in a radio access network (RAN) is provided. The apparatus is configured to perform other method aspects.

[0020] In a further aspect, there is provided an apparatus for transmitting system information for time division duplex (TDD) communication in a radio access network (RAN). The apparatus includes at least one processor and a memory. The memory includes instructions executable by the at least one processor, whereby the apparatus operates to transmit a master information block (MIB) on an anchor carrier for TDD communication in the RAN. The MIB indicates the spectral resources of system information blocks (SIBs) allocated for TDD communication in the RAN. Execution of the instructions also causes the apparatus to operate to transmit the SIBs on the spectral resources indicated in the MIB.

[0021] In a further aspect, there is provided an apparatus for receiving system information for time division duplex (TDD) communication in a radio access network (RAN). The apparatus includes at least one processor and a memory. The memory includes instructions executable by the at least one processor, whereby the apparatus operates to receive a master information block (MIB) on an anchor carrier for TDD communication in the RAN. The MIB indicates the spectral resources of system information blocks (SIBs) allocated for TDD communication in the RAN. Execution of the instructions also causes the apparatus to operate to receive the SIBs on the spectral resources indicated in the MIB.

[0022] The apparatus (e.g., any base station or radio device embodying the technology) may further include any feature disclosed in the context of any one of the method aspects. In particular, any apparatus may include units or modules configured to perform or trigger one or more of the steps of any one of the method aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Further details of embodiments of the present technology are described with reference to the accompanying drawings, in which:

[0024] Figure 1 A schematic block diagram of an apparatus for transmitting system information for time division duplex communication in a radio access network is shown;

[0025] Figure 2 A schematic block diagram of an apparatus for receiving system information for time division duplex communication in a radio access network is shown;

[0026] Figure 3 Shows the Figure 1 flowchart of a method for transmitting system information for time division duplex communication in a radio access network implemented by the apparatus;

[0027] Figure 4 Shows the Figure 2 flowchart of a method for receiving system information for time division duplex communication in a radio access network implemented by the apparatus;

[0028] Figure 5Schematically shows an exemplary radio access network for any device in a device for deployment Figure 1 and Figure 2 ;

[0029] Figure 6 Schematically shows a first example of a frequency band that can be used in a RAN of Figure 5 ;

[0030] Figure 7 Schematically shows Figure 6 the frequency structure of a mobile broadband system;

[0031] Figure 8 Schematically shows the center frequency of a PRB;

[0032] Figure 9 Schematically shows a set of uplink-downlink TDD configurations;

[0033] Figures 10A to 10C Schematically shows a third example of a frequency band that can be used in a RAN of Figure 5 ;

[0034] Figure 11 Schematically shows an example of an MBB frequency band that can be used in a RAN of Figure 5 ;

[0035] Figures 12A to 12C Schematically shows a fourth example of a frequency band that can be used in a RAN of Figure 5 ;

[0036] Figure 13 Schematically shows a grouping of radio blocks;

[0037] Figure 14A and Figure 14B Schematically shows a fifth example of a frequency band;

[0038] Figure 15 Shows Figure 1 a schematic block diagram of a first implementation of a device;

[0039] Figure 16 Shows Figure 1 a schematic block diagram of a second implementation of a device;

[0040] Figure 17 Shows Figure 2 a schematic block diagram of a first implementation of a device; and

[0041] Figure 18 Shows Figure 2 a schematic block diagram of a second implementation of a device. DETAILED DESCRIPTION

[0042] In the following description, for purposes of explanation and not limitation, specific details such as a particular network environment are set forth in order to provide a thorough understanding of the technology disclosed herein. It will be apparent to those skilled in the art that the technology may be practiced in other embodiments without these specific details. Additionally, while the following embodiments are primarily described with respect to 5G New Radio (NR) implementations, it will be readily understood that the technology described herein may also be implemented in any other radio network, including 3GPP LTE or its successors, wireless local area networks (WLANs) according to the IEEE 802.11 standard family, Bluetooth (in particular Bluetooth Low Energy and Bluetooth Broadcast) according to the Bluetooth Special Interest Group (SIG), and / or ZigBee based on IEEE 802.15.4.

[0043] Furthermore, those skilled in the art will understand that the functions, steps, units, and modules explained herein may be implemented using software acting in conjunction with a programmed microprocessor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), or a general-purpose computer (e.g., including an Advanced RISC Machine (ARM)). It will also be understood that while the following embodiments are primarily described in the context of methods and apparatuses, the invention may also be embodied in a computer program product and in a system including at least one computer processor and a memory coupled to the at least one processor, where the memory is encoded with one or more programs that can execute the functions and steps disclosed herein or implement the units and modules disclosed herein.

[0044] Figure 1 A block diagram of an apparatus for transmitting system information for time-division duplex (TDD) communication in a radio access network (RAN) is schematically shown. The apparatus is generally denoted by reference numeral 100.

[0045] Apparatus 100 includes a MIB transmission module 102 that transmits a master information block (MIB) on an anchor carrier for TDD communication in the RAN. The MIB indicates the spectral resources of system information blocks (SIBs) allocated for TDD communication in the RAN. Apparatus 100 also includes an SIB transmission module 104 that transmits SIBs on the spectral resources indicated in the MIB.

[0046] The system information may include or depend on at least one of the transmitted MIB and the transmitted SIB. Optionally, apparatus 100 may further include a TDD communication module 106 that performs TDD communication according to the system information by at least one of transmitting payload data, receiving payload data, and scheduling the transmission and / or reception of payload data.

[0047] Device 100 may be connected to and / or be part of a RAN. Device 100 may be embodied by or at the following: a base station of the RAN, one or more nodes connected to the RAN for controlling the base station, or a combination thereof. Any module in the modules of Device 100 may be implemented by a unit configured to provide the corresponding functionality.

[0048] The base station may cover a network controller of the RAN (e.g., a Wi-Fi access point according to IEEE 802.11) or a radio access node (e.g., a 3G Node B, a 4G eNodeB, or a 5G gNodeB). The base station may be configured to provide radio access to a plurality of radio devices.

[0049] System information, in particular the MIB and / or SIB, may be transmitted (e.g., broadcast) to one or more radio devices. Each radio device may be configured to wirelessly connect to the RAN, in particular to a base station of the RAN.

[0050] In addition, the TDD communication may be narrowband (NB) communication. Some or each of the radio devices may be configured for NB communication in the RAN. Some or each of the radio devices may be NB Internet of Things (NB-IoT) devices.

[0051] Alternatively or additionally, some or each of the radio devices may be, for example, a user equipment (UE) according to 3GPP, and / or a mobile or portable station according to, for example, IEEE 802.11. Two or more than two radio devices may be configured to wirelessly connect to each other according to the system information, for example, in an ad-hoc radio network or via a 3GPP side link.

[0052] Figure 2 A block diagram of a device for receiving system information for time division duplex (TDD) communication in a radio access network (RAN) is schematically shown. The device is generally denoted by reference numeral 200.

[0053] Device 200 includes a MIB receiving module 202 that receives a master information block (MIB) on an anchor carrier of the TDD communication in the RAN. The MIB indicates the spectral resources of system information blocks (SIBs) allocated for the TDD communication in the RAN. Device 200 further includes a SIB receiving module 204 that receives the SIB on the spectral resources indicated in the MIB.

[0054] The system information may include or depend on at least one of the received MIB and the received SIB. Optionally, the apparatus 200 may further include a TDD communication module 206 that performs TDD communication according to the system information by receiving payload data, transmitting payload data, and being scheduled for at least one of receiving and / or transmitting payload data.

[0055] The apparatus 200 may be connected to, embodied by, and / or be part of a radio device. Any of the modules of the apparatus 200 may be implemented by units configured to provide the corresponding functionality.

[0056] The radio device may be configured to wirelessly connect to the RAN based on the system information, particularly to a base station of the RAN. The radio device may be, for example, a user equipment (UE) according to 3GPP and / or a mobile or portable station according to, for example, IEEE 802.11 (Wi-Fi). Alternatively or additionally, the radio device may be configured to wirelessly connect to another embodiment of a radio device, for example, in an ad-hoc radio network or via a 3GPP side link, based on the system information.

[0057] The TDD communication may be narrowband (NB) communication. The radio device may be configured for NB communication in the RAN. The radio device may be an NB Internet of Things (NB-IoT) device.

[0058] The base station may cover a network controller of the RAN (e.g., a Wi-Fi access point) or a radio access node (e.g., a 3G Node B, a 4G eNodeB, or a 5G gNodeB). The base station may be configured to provide radio access to the radio device.

[0059] Figure 3 A flowchart of a method 300 for transmitting system information for time division duplex (TDD) communication in a radio access network (RAN) is shown. The method includes or triggers the following steps 302: Transmit a master information block (MIB) on an anchor carrier for TDD communication in the RAN. The MIB indicates the spectral resources of system information blocks (SIBs) allocated for TDD communication in the RAN. In step 304 of method 300, transmit the SIB on the spectral resources indicated in the MIB.

[0060] The system information may be derivable using at least one of the transmitted MIB and the transmitted SIB. Optionally, in step 306, perform TDD communication in the RAN based on the system information.

[0061] Method 300 may be performed by apparatus 100, for example, at or using a base station of a RAN. For example, modules 102 and 104 may perform steps 302 and 304, respectively.

[0062] Figure 4 A flowchart of a method 400 for receiving system information for time division duplex (TDD) communication in a radio access network (RAN) is shown. The method includes or triggers the following steps 402: Transmit a master information block (MIB) on an anchor carrier of TDD communication in the RAN. The MIB indicates spectral resources of system information blocks (SIBs) allocated for TDD communication in the RAN. In step 404 of method 400, receive the SIB on the spectral resources indicated in the MIB.

[0063] The system information may be derived using at least one of the transmitted MIB and the transmitted SIB. Optionally, in step 406, perform TDD communication in the RAN based on the system information.

[0064] Method 400 may be performed by apparatus 200, for example, at or using a radio device. For example, modules 202 and 204 may perform steps 402 and 404, respectively.

[0065] Any feature or step described for an embodiment of apparatus 100 may be implemented in method 300, and an embodiment of apparatus 200 and an implementation of method 400 may include corresponding features or steps. That is, apparatus 100 and 200 and methods 300 and 400 are different aspects of the technology.

[0066] The technology may enable indication of SIBs (e.g., SIB1-NB) on non-anchor carriers of NB-IoT TDD. A low number or a minimum number of bits in the MIB (e.g., MIB-NB) may signal the spectral resources (e.g., non-anchor carrier positions) carrying the SIB (e.g., SIB1-NB) and provide flexibility to reduce the impact on coexisting mobile broadband (MBB) systems (e.g., legacy LTE systems).

[0067] By applying the technology, a network (e.g., a RAN and / or a core network connected to the RAN) may indicate a non-anchor carrier to a radio device (e.g., a UE) on which the SIB (e.g., SIB1-NB) is transmitted, where several SIB-specific bits are in the MIB (e.g., MIB-NB).

[0068] The technology allows use of a common format of the MIB (e.g., MIB-NB) for multiple (e.g., all three) deployments (e.g., NB-IoT operation modes) including at least one of in-band deployment, guard band deployment, and stand-alone deployment.

[0069] The MIB (e.g., MIB-NB) for TDD communication (e.g., for NB-IoT TDD communication) may indicate the configuration of the carrier on which the SIB (e.g., SIB1-NB carrier) is transmitted to assist the device 100 (e.g., a radio device, particularly a UE) in determining the SIB carrier. For example, the configuration of the SIB carrier in the MIB may consist of a field indicating whether the SIB is on the anchor carrier or on a non-anchor carrier. Alternatively or additionally, an extension of the existing operating mode information may provide a deployment-specific (e.g., operating mode-related) configuration of the SIB.

[0070] The device 100 (e.g., a radio device, particularly module 206) may determine the exact spectral resources (e.g., NB-IoT non-anchor carrier) based on predefined rules (e.g., specified in 3GPP technical specifications) in combination with the indication (e.g., SIB1-NB carrier configuration) broadcast in the MIB (e.g., MIB-NB) on which the SIB (e.g., SIB1-NB) is transmitted in step 304 and received in step 404.

[0071] In an NB-IoT system configured for TDD, the downlink (i.e., transmission from the base station of the RAN to the UE) and the uplink (i.e., transmission from the UE to the base station) share the same carrier frequency in a time-division manner defined by the uplink-downlink TDD configuration.

[0072] The initial synchronization signals include the NB primary synchronization signal (NPSS) and the NB secondary synchronization signal (NSSS) signals transmitted on the anchor carrier. For example, according to the RAN1 chair's note of 3GPP TSG RAN WG1 meeting 90bis (Prague, CZ, October 9 - 13, 2017), the MIB-NB broadcast to the NPBCH covering the entire cell is also transmitted on the anchor carrier.

[0073] Embodiments of the technique enable the RAN (e.g., a base station) to transmit the SIB (e.g., SIB1-NB) on one or more non-anchor carriers and optionally transmit one or more other SIBs. If the SIB is transmitted on a non-anchor carrier, the MIB (e.g., MIB-NB) notifies the UE about the exact spectral resources (i.e., non-anchor carrier) of the SIB so that the UE can tune its receiver to that specific carrier to receive the SIB and optionally receive other SIBs.

[0074] Embodiments of the technique use a limited number of spare bits in the MIB to indicate the spectral resources of the SIB (e.g., SIB1-NB carrier). By using this technique, the spectral resources for the SIB can be deployed with great flexibility at many possible frequency positions, e.g., according to the system definition.

[0075] Contrary to embodiments of techniques that use one or several bits to indicate the spectral resources of SIBs in the MIB, the conventional way of indicating NB-IoT non-anchor carriers, as defined by 3GPP Release 14 (e.g., in section 5.7.3 of document 3GPP TS 36.104 (e.g., version 14.5.0)), requires 23 bits, including 18 bits for indicating the E-UTRA absolute radio frequency channel number (EARFCN) and another 5 bits for the frequency offset of the carrier raster in the SIB. Due to the limited size of MIB-NB, such a number of bits is not suitable for MIB-NB.

[0076] This technique can be applied to the trade-off between the flexibility of spectral resources (e.g., the SIB1-NB position in the frequency domain) and the number of bits indicating spectral resources in the MIB. By predefining the spectral resources (e.g., the position of the non-anchor carrier) carrying the SIB (e.g., SIB1-NB) or by predefining several candidates for the spectral resources, the number of bits used in the MIB can be minimized.

[0077] The SIB can be SIB type 1 or SIB1, which is, for example, compatible with the SystemInformationBlockType1-NB (SIB1-NB) specified in document 3GPP TS 36.331 (e.g., version 14.4.0). The transmission of the MIB and / or the transmission of the SIB can be broadcast. The system information can include at least one of the MIB and the SIB.

[0078] By indicating the spectral resources carrying the SIB (e.g., SIB1) in the MIB, sufficient system information for flexibly configuring TDD communication can be transmitted without the disproportionate signaling overhead caused by the MIB on the anchor carrier. For example, the MIB of the same structure or size can be transmitted in different or all deployment modes and / or in different or all uplink-downlink TDD configurations (including uplink-downlink configurations with scarce or minimal downlink resources).

[0079] In one implementation, it may be impossible to transmit in the downlink on a non-anchor carrier in a subframe configured for uplink according to the uplink-downlink-TDD configuration. In other words, in some implementations, the same uplink-downlink configuration can be applied to both the anchor carrier and the non-anchor carrier.

[0080] The spectral resources can be indicated in the frequency domain as, for example, the center frequency, subcarriers, frequency ranges, and / or one or more physical resource blocks (PRBs).

[0081] The spectrum resources may include at least one non-anchor carrier for the transmission of SIB, and the non-anchor carrier is different from the anchor carrier. More than one non-anchor carrier may be used to increase the capacity.

[0082] The anchor carrier may also be referred to as the primary carrier. The non-anchor carrier may also be referred to as the secondary carrier. The non-anchor carrier may not overlap with the anchor carrier and / or be adjacent (e.g., neighboring) to the anchor carrier.

[0083] The MIB may indicate whether the spectrum resources are on the anchor carrier or on a carrier other than the anchor carrier. The MIB may indicate whether the spectrum resources (e.g., the transmission of SIB) are on the anchor carrier or on the non-anchor carrier.

[0084] The MIB may include at least one parameter value or indicator indicating the spectrum resources. For example, the MIB may include an index value and / or bit field indicating (e.g., referring to) frequency, subcarrier, frequency range, and / or one or more PRBs. The MIB may indicate the absolute frequency and / or absolute frequency range of the spectrum resources. Alternatively or in combination, the MIB may indicate the relative position and / or size of the spectrum resources (e.g., the relative position of frequency, subcarrier, frequency range, and / or one or more PRBs).

[0085] The MIB may indicate the spectrum resources relative to the anchor carrier. Alternatively or in combination, the MIB may indicate the spectrum resources in terms of physical resource blocks (PRBs).

[0086] The MIB may indicate the spectrum resources of the grid of a reference PRB. At least one of the center frequency and bandwidth of the spectrum resources may be indicated in terms of PRBs.

[0087] The method may further include or trigger the following steps: transmitting an initial synchronization signal on an anchor carrier for TDD communication in the RAN. The initial synchronization signal may include at least one of the primary synchronization signal (PSS, e.g., NB PSS or NPSS) and the secondary synchronization signal (SSS, e.g., NB SSS or NSSS) of the RAN.

[0088] The transmission on the anchor carrier and / or non-anchor carrier may be managed by the uplink-downlink configuration of TDD communication in the RAN. The uplink-downlink configuration of TDD communication may associate the subframes of the TDD communication with the communication directions. The uplink-downlink configuration of TDD communication may be compatible with those in Table 4.2-2 of 3GPP document TS 36.211 for frame structure type 2 (e.g., version 14.4.0). For example, the uplink-downlink configuration of TDD communication in the RAN may be determined from a subset of the uplink-downlink configurations.

[0089] The method may further comprise or trigger the following steps: selectively transmitting and receiving payload data on an anchor channel according to an uplink-downlink configuration of TDD communication in the RAN.

[0090] System information (e.g., MIB or SIB) and / or downlink control information (DCI) may indicate the uplink-downlink TDD configuration. There may be 6 or 7 uplink-downlink TDD configurations, and one of them may be configured at the radio device by indicating the corresponding configuration in the MIB, SIB (e.g., SIB1) or in the DCI. The uplink-downlink TDD configuration may be compatible with those defined in document 3GPP TS 36.331 (e.g., version 14.4.0).

[0091] In addition, different uplink-downlink TDD configurations may be applied to different carriers. The anchor carrier and one or more non-anchor carriers may use different uplink-downlink TDD configurations. Such different uplink-downlink TDD configurations may be indicated in the MIB. Alternatively or additionally, if the SIB1 scheduling is the same for all uplink-downlink TDD configurations (e.g., in subframe #0 and / or subframe #1), the uplink-downlink TDD configuration may be included in the SIB1. Otherwise, the uplink-downlink TDD configuration may be included in the MIB.

[0092] TDD communication in the RAN may be NB radio communication involving NB devices. NB devices may also be referred to as NB radio devices or NB Internet of Things (IoT) devices, i.e., NB IoT devices. NB IoT devices may perform a random access procedure with the RAN based on at least one of the initial synchronization signal, MIB, and SIB. For example, the RAN may receive a random access preamble from the NB IoT device.

[0093] At least one of the system information (SI), MIB, and SIB may refer to NB communication. At least one of the SI, MIB, and SIB may be referred to as SI-NB, MIB-NB, and SIB-NB, respectively.

[0094] The system bandwidth of NB communication (i.e., NB system bandwidth) can be equal to or (e.g., significantly) less than the coherence bandwidth of NB communication. The coherence bandwidth can include a statistical measure of a frequency range over which a radio channel can be considered flat, or a bandwidth or frequency separation over which two frequency components of a radio signal may experience comparable or correlated (e.g., amplitude) fading. The NB system bandwidth (e.g., UE bandwidth) can cover at least one of the anchor carrier and non-anchor carriers. The NB bandwidth can be 200 kHz (or 1 PRB, as the useful bandwidth) for NB communication. More particularly, from the perspective of an NB radio device, the NB bandwidth can be less than the coherence bandwidth of NB communication. Additionally, the RAN can configure several non-anchor carriers at different locations, in which case the correlation may fade.

[0095] The RAN can also provide radio access to mobile broadband (MBB) devices for MBB communication in the MBB system bandwidth of the RAN, where the NB used for NB communication is deployed within the MBB system bandwidth or in the guard band of the MBB system bandwidth.

[0096] The system bandwidth of MBB communication (i.e., MBB system bandwidth) can be greater than the NB system bandwidth used by NB communication (e.g., several times the NB system bandwidth used by NB communication). Alternatively or in combination, the MBB system bandwidth can cover a bandwidth of at least or more than 6 PRBs to communicate with one radio device (e.g., UE).

[0097] The MBB system bandwidth can (e.g., significantly) exceed the coherence bandwidth of MBB communication, e.g., the coherence bandwidth of the MBB channel used by MBB communication. The transfer function of the MBB channel can be frequency-dependent within the MBB system bandwidth.

[0098] MBB devices and NB IoT devices can coexist within the coverage area (e.g., cell or sector) of the RAN. The NB IoT device can be configured to transmit and / or receive in the NB system bandwidth. The NB system bandwidth can correspond to one or several (e.g., 2 or 3) PRBs, 1 to 12 subcarriers, and / or 15 kHz to 180 kHz or 200 kHz. The MBB device can be configured to transmit and receive in the MBB system bandwidth corresponding to multiple PRBs, more than 12 subcarriers, and / or greater than 180 kHz or 200 kHz.

[0099] MBB communication can use frequency division duplexing (FDD) or TDD. In the case of TDD for MBB communication, the same uplink-downlink configuration can be applied to both NB communication and MBB communication in the RAN.

[0100] In addition, non-anchor carriers can be (e.g., selectively) used for both uplink and downlink.

[0101] The NB system bandwidth can cover at least one of the anchor carrier and non-anchor carriers. One or more non-anchor carriers can be arranged in any PRB of the MBB system, e.g., in addition to the middle 6 PRBs in the LTE system.

[0102] The PRBs for MBB communication can be arranged in the frequency domain according to a PRB scheme. Alternatively or additionally, the anchor carriers for NB communication can be arranged in the frequency domain according to a carrier grid. The PRB interval of the PRB scheme can be greater than the carrier interval of the carrier grid. The PRB interval can be 180 kHz. The carrier interval can be 100 kHz.

[0103] The anchor carrier can use PRBs according to the PRB scheme. The offset between the center frequency of the PRB and the carrier of the carrier grid can be equal to or less than 7.5 kHz and / or half of the subcarrier spacing. The subcarrier spacing can be 15 kHz. The offset can be equal to or less than 7.5 kHz or 2.5 kHz. For example, the offset can be small enough such that even if the NB IoT device scans on the carrier grid, it detects the anchor carrier. For example, the frequency of the anchor carrier can be close to the least common multiple of the PRB spacing and the carrier spacing.

[0104] The non-anchor carrier can use another PRB that is adjacent to the PRB of the anchor carrier according to the PRB scheme. The PRB adjacent to one of the anchor carriers can be adjacent or neighboring to the PRB of the anchor carrier.

[0105] At least one of the anchor carrier and non-anchor carriers for NB communication can be located in one or more guard bands of the MBB system bandwidth. The MIB can indicate whether the anchor carrier and non-anchor carrier are located in the same guard band or in opposite guard bands of the MBB system bandwidth.

[0106] The anchor carrier can be closer to the frequency edge of the MBB system bandwidth. Alternatively or in combination, the anchor carrier can be equal to or located at the frequency edge of the MBB system bandwidth.

[0107] Alternatively or additionally, the anchor carrier can be closer to the MBB carrier frequency than the non-anchor carrier, or the anchor carrier and non-anchor carrier can be symmetrically arranged in the frequency domain with respect to the MBB carrier frequency.

[0108] The anchor carrier can be arranged between the MBB system bandwidth and the non-anchor carrier. For example, the MIB can indicate whether the non-anchor carrier for transmitting the SIB corresponds to the PRB adjacent to the frequency edge of the MBB system bandwidth of the RAN or the second PRB adjacent to the frequency edge of the MBB system bandwidth of the RAN.

[0109] The MIB may indicate whether the non-anchor carrier for transmitting the SIB is a guard band located at the lower frequency edge of the MBB system bandwidth or a guard band located at the higher frequency edge of the MBB system bandwidth.

[0110] The MIB may indicate whether the non-anchor carrier for transmitting the SIB is at a frequency lower than the lower frequency edge of the MBB system bandwidth or at a frequency higher than the higher frequency edge of the MBB system bandwidth.

[0111] At least one of the anchor carrier and the non-anchor carrier for NB communication may be within the MBB system bandwidth. At least one of the anchor carrier and the spectrum resource for transmitting the SIB of NB communication may be within the MBB system bandwidth.

[0112] The MIB may indicate whether the spectrum resource for transmitting the SIB is arranged in the PRBs adjacent to the lower frequency edge of the PRBs used by the anchor carrier or in the PRBs adjacent to the higher frequency edge of the PRBs used by the anchor carrier.

[0113] Alternatively or additionally, the MIB may indicate the subframe for transmitting the SIB (e.g., on the anchor carrier).

[0114] The 3GPP NB-IoT implementation of the technology for NB communication may be compatible with the NB system defined by 3GPP for cellular Internet of Things (IoT). The NB system uses a physical layer optimized for very low power consumption to provide access to network services. The full carrier bandwidth of NB may be 180 kHz, and the subcarrier spacing may be 3.75 kHz or 15 kHz. The NB system may be based on an existing MBB system (e.g., an LTE system) and address an optimized network architecture and improved indoor coverage for a large number of NB-IoT radio devices (also referred to as NB radio devices or NBIoT devices).

[0115] Any NB-IoT radio device may include at least one of the following characteristics. The first characteristic may include the low throughput of the NB-IoT radio device, e.g., 2 kbps or less. The second characteristic may include low sensitivity to latency or delay, e.g., low sensitivity to latency or delay on the order of 10 seconds or greater than 10 seconds. The third characteristic may include the low cost of manufacturing the NB-IoT radio device, e.g., less than $5. The fourth characteristic may include the low power consumption of the NB IoT device, e.g., a battery life on the order of 10 years or longer.

[0116] Figure 5An embodiment of the RAN 500 in which the technology can be implemented is schematically shown. The RAN 500 includes at least one embodiment of the apparatus 100, for example, at the base station 510. TDD communication involves at least one NBTDD communication 502 with the NB radio device 512. Each radio device in the radio device 512 embodies the apparatus 200. As Figure 5 schematically shown, the NB communication 502 can coexist with the mobile broadband (MBB) communication 504 involving the MBB radio device 514.

[0117] Not limited to Figure 5 the RAN 500 schematically shown, the carrier bandwidth of the NB communication 502 can be 180 kHz or less, for example, as opposed to the bandwidth of the MBB communication 504. The anchor carrier or any carrier of the NB communication can be used in a first mode with a single subcarrier (or tone) having a 15 kHz and / or 3.75 kHz subcarrier spacing, or in a second mode with multiple subcarriers (or multi-tones) transmission having a 15 kHz subcarrier spacing. In addition, the NB communication, for example, does not support turbo codes for the downlink, for example, as opposed to the MBB communication.

[0118] Examples of the MBB radio device 514 include mobile stations such as mobile phones or tablet computers, and portable stations such as laptop computers or televisions. Examples of the NB radio device 512 include robots, sensors, and / or actuators in, for example, manufacturing, automotive communication, and home automation. The NB radio device can be implemented in household appliances and consumer electronics. Embodiments of the combination of the MBB radio device 514 and the NB radio device 512 can include autonomous vehicles, door intercommunication systems, and automated teller machines.

[0119] Examples of the base station 510 can include 3G base stations or Node Bs, 4G base stations or eNodeBs, 5G base stations or gNodeBs, access points (e.g., Wi-Fi access points), and network controllers (e.g., according to Bluetooth, ZigBee, or Z-Wave).

[0120] The RAN 500 can be compatible with the Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), and / or 5G New Radio (NR).

[0121] Aspects of the present technology can be implemented on the physical layer (PHY), media access control (MAC) layer, radio link control (RLC) layer, and / or radio resource control (RRC) layer of a protocol stack for radio communication.

[0122] Each base station 510 of the RAN 500 can provide radio access in one or more cells or sectors. The coverage area of each cell or sector can be on the order of 1 km 2 (1 square kilometer). Each cell or sector can serve thousands of (e.g., more than 10,000 or on the order of 50,000) NB-IoT radio devices, such as sensors, meters, actuators, etc. The narrow bandwidth 612 of the NB 602 can utilize the existing spectrum such as GSM. That is, the NB 602 can be deployed on the GSM spectrum. The carrier grid of the NB-IoT system including a 100 kHz frequency step can be consistent with the 200 kHz grid used for GSM.

[0123] Figure 6 A first example of the frequency band 600 for wireless communication in the RAN 500 (e.g., according to the exemplary RAN 500 shown in Figure 5 ) is schematically shown. The NB 602 (i.e., the part of the frequency band 600 for NB TDD communication 502) can be differently deployed relative to or independently of the MBB 604 used for or available for MBB communication 504.

[0124] For clarity and not limitation, in Figure 6 one NB-IoT carrier is shown as NB 602. Each NB-IoT carrier can occupy a bandwidth of 180 kHz, for example, corresponding to one PRB in the MBB 604 allocated to the NB TDD communication 502.

[0125] The NB-IoT carrier 602 shown can be used as the anchor carrier for the NB TDD communication 602. Alternatively, one or more non-anchor carriers can be deployed as schematically illustrated at one or more of the reference numerals 602. In addition, the anchor carrier and one or more non-anchor carriers can be arranged (e.g., right next to each other) at one or more of the reference numerals 602.

[0126] Figure 6 The deployment (also referred to as the operating mode) of the NB 602, e.g., the anchor carrier and / or non-anchor carriers, is schematically depicted. The deployment includes in-band deployment, guard band deployment, and stand-alone deployment as schematically shown from left to right. If the NB 602 is within the MBB 604 used for or available for MBB communication 504, the NB 602 is deployed within the MBB 604 band. In guard band deployment, the NB 602 is located in the guard band 606 of the MBB 604. In stand-alone deployment, the NB 602 is located in the NB dedicated frequency range, e.g., in the absence of the MBB 604, or the NB dedicated frequency range is independent of the coexisting MBB 604.

[0127] Three different operation modes (i.e., Standalone, Guard Band, and In-Band) can be compatible with 3GPP RP-152284 ["New Work Item: NarrowBand IoT (NB-IoT)", Huawei and HiSilicon, RAN#70]. In Standalone deployment, the NB-IoT system operates in a dedicated frequency band. For In-Band deployment, the NB 602 is placed within the frequency band 604 used by or available for a coexisting MBB system (e.g., an LTE system). In Guard Band deployment, the NB 602 is placed in the guard band 606 of a coexisting MBB system (e.g., an LTE system), i.e., near the edge of the MBB 604, as Figure 6 schematically shown in

[0128] The NB-IoT system can operate, for example, with an NB system bandwidth 612 of 180 kHz or a multiple thereof for multi-carrier operation depending on the deployment of one or more non-anchor carriers. When configuring multiple carriers, for example, according to 3GPP R1-161548 ["RAN1 Protocol for Rel-13 NB-IoT", Work Item Rapporteur Ericsson, 3GPP TSG-RAN WG1 Meeting #84, St. Julian's, Malta, February 15 - 19, 2016], several PRBs each having a bandwidth of 180 kHz can be used, e.g., for increasing the NB system capacity, for inter-cell interference coordination and / or load balancing.

[0129] According to some MBB resource allocations (e.g., LTE resource allocation type 0, which is the most commonly used resource allocation type), the physical resource blocks (PRBs) of the MBB 604 are grouped into resource block groups (RBGs) to be scheduled to the MBB radio device 514 (e.g., a UE). Depending on the MBB channel bandwidth or MBB system bandwidth 608, the number of PRBs in each RBG varies from 1 to 4. The channel bandwidth of the MBB604 can be defined as the bandwidth occupied by the MBB 604 including the guard band 606. The MBB system bandwidth 608 can be defined by the transmission bandwidth configuration of the MBB 604, e.g., in terms of PRBs.

[0130] For in-band deployment of NB TDD communication 502, the use of RBGs can segment MBB (e.g., LTE) resource allocation, since narrowband reference signals (NRSs) are used for NB TDD communication 502 as downlink reference signals, a feature not present in traditional LTE UEs. Thus, for in-band deployment of NB 602, the anchor carrier and one or more non-anchor carriers are preferably in the same RBG of MBB 604. The preferred embodiment uses all the PRBs of the RBG for NB TDD communication 502 in in-band deployment before using another RBG. This RBG filling rule can also be applied to RBGs that include only non-anchor carriers of NB TDD communication 502.

[0131] For guard band deployment, the same or a further preferred embodiment places the anchor carrier and non-anchor carriers at different band edges of MBB 604, e.g., to meet requirements for limiting out-of-band emissions. For example, NB 602 can be located between the remaining portion 610 of guard band 606 and the system bandwidth 608 of MBB 604. As a result, the complexity of filter design can be reduced, especially if the non-anchor carriers are also power-boosted.

[0132] Figure 7 An exemplary frequency structure of MBB 604 is schematically shown, which exemplary frequency structure can be part of a first example or another second example of the frequency band 600 used by RAN500.

[0133] The system bandwidth 608 of MBB 604 includes a plurality (N RB ) PRBs 700 configured according to the transmission bandwidth of MBB 604. A limit 702 on out-of-band emissions is schematically shown. The channel bandwidth 609 encompasses both the system bandwidth 608 and the guard band 606. A subset 704 of the PRBs 700 is used by MBB communication 504, such that some of the other PRBs 700 can be allocated to NB TDD communication 502 in in-band deployment. The central sub-carrier 706 corresponding to the direct current (DC) component in the baseband is not transmitted in the downlink of RAN 500.

[0134] The channel raster of the downlink of the NB-IoT system is on a 100 kHz frequency grid. That is, the NB IoT device 512 searches for NB-IoT carriers (more specifically, the anchor carrier) in 100 kHz step sizes, which can be directly implemented in stand-alone deployments. For in-band and guard band deployments, as observed in 3GPP document R1-160082 ["NB-IoT Channel Raster", Ericsson, 3GPP TSG-RAN1 NB-IoT Ad Hoc, January 18 - 20, 2016, Budapest, Hungary], due to the presence of the DC carrier 706 and the fact that the center of the PRB 700 is between two subcarriers of the MBB 604, there is no PRB 700 that directly falls on the NB cell search grid used in LTE in-band operation. For even and odd PRBs 700 in the LTE system bandwidth 608, the minimum frequency offsets from the 100 kHz grid are ±2.5 kHz and ±7.5 kHz, respectively.

[0135] In Figure 8 the center frequencies 800 and 802 of the PRB 700 are schematically shown for in-band deployments with an even (upper row) and odd (middle row) number of PRBs and for guard band deployments (lower row). Those center frequencies at reference numeral 802 are examples of the minimum offsets. A detailed description of matching the MBB PRB structure and the NB carrier raster with the minimum offsets is given in the aforementioned 3GPP document R1-160082 and 3GPP document R1-160022 ["Channel Raster Design", source Huawei, HiSilicon, 3GPP TSG-RAN1 NB-IOT Ad Hoc January 18 - 20, 2016, Budapest, Hungary]. The minimum offsets of ±2.5 kHz or ±7.5 kHz can be handled by the NB radio device 512 during the cell search process and then compensated, for example, as discussed in 3GPP documents R1-160080 ["NB-IoT - Synchronization Channel Assessment", Ericsson, 3GPP TSG-RAN1 NB-IoT Ad Hoc, January 18 - 20, 2016, Budapest, Hungary] and R1-160021 ["Synchronization Signal Assessment", Huawei and HiSilicon, 3GPP TSG-RAN1 NB-IoT Ad Hoc, January 18 - 20, 2016, Budapest, Hungary].

[0136] The minimum offset defines a constraint on the position of the deployable NB-IoT carrier (more specifically: the anchor carrier) for in-band and guard-band operations. Thus, the NB-IoT downlink carrier (i.e., the anchor carrier) containing some of the system information in the synchronization signal and system information can only be placed at the center frequency close to (in the sense of the minimum offset) one of the 100 kHz grids or grid points. In addition, the middle 6 PRBs 804 are not allowed to be used by NB TDD communication because these PRBs 804 are used by MBB, for example, for its broadcast control channel.

[0137] Thus, the NB-IoT UE 512 is only required to search for carriers on the 100 kHz grid. The NB-IoT carrier intended to facilitate the initial synchronization of the NB-IoT UE is called the anchor carrier. The 100 kHz NB-IoT UE search grid means that for in-band deployment and guard-band deployment, the anchor carrier can only be placed in certain PRBs 700 at the center frequency 802. The NB-IoT anchor carrier in such a deployment needs to have a center frequency 802 that is no greater than 7.5 kHz from the 100 kHz grid. The NB-IoT cell search and initial acquisition performed by the NB UE 512 can synchronize with the RAN 500 in the presence of a grid offset of up to ±7.5 kHz.

[0138] Multi-carrier operation of NB-IoT is supported in NB TDD communication 502 based on the MIB and optionally based on one or more SIBs transmitted subsequently. Since it is sufficient to have one NB-IoT anchor carrier to facilitate UE initial synchronization, the additional carriers do not need to be centered around the 100 kHz grid. These additional carriers are called secondary carriers or non-anchor carriers.

[0139] This technology can be implemented according to the further enhancement (feNB-IoT) of NB-IoT under the work item in 3GPP document RP-171428, ["NB_IOTenh2, Revised WID on Further NB-IoT Enhancements", Huawei and HiSilicon, 3GPP TSG RAN Meeting #76, West Palm Beach, USA, June 5 - 8, 2017].

[0140] The MBB channel bandwidth 609 can be related to the number of N RB PRBs, i.e., according to Table 5.6-1 of 3GPP TS 36.106 (e.g., version 14.0.0) or according to the transmission bandwidth 608 in the following table.

[0141]

[0142] The indexes of exemplary PRBs available as anchor carriers in the in-band deployment of NB 602, for example for a fully operational cell deployment for NB-IoT, are outlined in the table below.

[0143]

[0144]

[0145] As used herein, the expression "fully operational cell" may or may not be a term used by 3GPP specifications. It is used for concise and clear understanding of the present disclosure. This expression refers to a cell that provides radio access to an NB-IoT UE 512. That is, the cell provides an anchor carrier on the grid where the NB-IoT UE 512 initially searches. The anchor carrier provides all necessary information for radio access (e.g., synchronization signals, reference symbols, and / or broadcast information), and can be used for dedicated NB TDD communication 502.

[0146] Figure 9 A set of uplink-downlink TDD configurations 900 is schematically shown. Each row represents a different uplink-downlink TDD configuration 900, which is indicated by the corresponding index shown to the left in Figure 9 Time increases from left to right in each row.

[0147] Each box represents a subframe 902. Subframes marked "D" are for downlink communication, subframes marked "U" are for uplink communication, and subframes marked "S" are split to include portions for both downlink and uplink communication.

[0148] At least a subset of the uplink-downlink TDD configurations 900 schematically shown can be used for, for example, NB TDD communication 502 and / or MBB communication 504 in an LTE-TDD radio frame.

[0149] This technique implements TDD in NB 602. TDD is supported in combination with the in-band, guard band, and stand-alone operation modes of NB 602. In a first implementation, the NB UE 512 does not require an uplink compensation gap. In a second implementation combinable with the first implementation and any embodiments described herein, a common message format (e.g., for the MIB) is used for the deployment mode. Additionally, compared to MBB communication 504 and / or existing NB-IoT systems (e.g., according to 3GPP Release 13), for NB communication 502, the limitations on the maximum coupling loss (MCL), latency, and / or capacity target can be relaxed. Alternatively or additionally, a third implementation can include a small cell scenario for NB communication 502.

[0150] In LTE-TDD, as a non-limiting example of MBB 604, to support flexible downlink and uplink partitioning, several configurations are supported, such as Figure 9 as shown. Each uplink-downlink TDD configuration in uplink-downlink TDD configuration 900 has a different number of uplink and downlink subframes 902. To coexist with LTE-TDD 604 in in-band and guard-band operation modes, NB-IoT TDD 602 is preferably configured with the same uplink-downlink configuration as the uplink-downlink configuration used by LTE-TDD. Additionally, for example, in embodiments of the present technology (i.e., in an exemplary NB-IoT TDD system), LTE-TDD UL-DL configuration #0 in Figure 9 is not supported. Optionally, the subset of NB-supported configurations in uplink-downlink TDD configuration 900 for MBB 604 can be further reduced [see RAN1 Chair's Note, 3GPP TSG RAN WG1 Meeting 90bis, Prague, CZ, October 9 - 13, 2017]. Any embodiment described herein can be implemented to support all LTE-TDD configurations 900 except LTE-TDD UL-DL configuration #0. Preferably, when operating as an in-band or guard-band deployment, NB TDD communication 502 uses one of the uplink-downlink TDD configurations 900 that is compatible with the coexisting MBB 604 (e.g., an LTE-TDD configuration).

[0151] As in other cellular networks such as GSM, WCDMA, and LTE, for example, in step 406, to access the RAN 500 as an NB-IoT network, the UE 512 first starts a cell search process. The UE 512 performs NPSS and NSSS detection to achieve frequency and time synchronization to the RAN 500. This is done on the anchor carrier. The relative time position of the NSSS with respect to the NPSS implicitly indicates whether the NB-IoT system is operating in FDD mode or TDD mode (e.g., according to the aforementioned RAN1 Chair's Note).

[0152] After achieving frequency and time synchronization and knowing the FDD or TDD mode, in step 402, the NB UE 512 continues to receive the NB Physical Broadcast Channel (NPBCH) on the anchor carrier to obtain the MIB-NB, which contains preliminary cell information and scheduling information for SIB1-NB transmission as the spectral resources for the SIBs. After obtaining the MIB-NB, in step 404, the NB UE 512 receives SIB1-NB according to the scheduling (i.e., on the spectral resources indicated in the MIB-NB). Optionally, SIB1-NB in turn indicates the spectral resources (e.g., scheduling information) for receiving additional System Information Blocks (SIBs). After having obtained all relevant system information, the NB UE 512 starts to access the network service according to other procedures defined in the 3GPP specifications for NB-IoT.

[0153] In the NB-IoT TDD system, after obtaining the MIB-NB in step 402, the NB UE 512 determines whether SIB1-NB is transmitted on the anchor carrier (i.e., the NB-IoT carrier on which the NB UE 512 detects NPSS and NSSS and decodes NPBCH) as the spectral resources allocated for the SIBs or on a non-anchor carrier as the spectral resources allocated for the SIBs. If SIB1-NB is transmitted on a non-anchor carrier, the NB UE 512 determines the exact position of the non-anchor carrier on which SIB1-NB is transmitted. In one variant of any embodiment, this information is provided in the MIB-NB by indicating the spectral resources allocated for the SIBs. In another variant of any embodiment, this information is predefined (e.g., hard-coded).

[0154] The following Abstract Syntax Notation One (ASN.1) is according to the definition of the MIB-NB for NB-IoT in the 3GPP Release 14 for the Frequency Division Duplex (FDD) mode. This MIB-NB can serve as a non-limiting starting point for illustrating the subject technology. Subsequent specifications for NB TDD communication 502 may use different definitions of the MIB-NB. For example, the MIB-NB may include a subset of the parameters indicated below.

[0155] The MIB-NB for NB TDD communication 502 transmitted and received according to steps 302 and 402 respectively may include at least some of the following parameters and at least one of the additional parameters emphasized in bold below for indicating the spectral resources of the SIBs.

[0156]

[0157] Figures 10A to 10CSchematically illustrated are examples of frequency bands 600, each of which may be used by the RAN 500 in any embodiment. The example frequency band 600 includes a NB-IoT TDD guard band deployment of a NB 602 relative to an LTE frequency band 609 having a channel bandwidth of 20 MHz. Without limitation, the schedulable LTE system bandwidth 608 includes 100 PRBs.

[0158] NB 602 includes anchor carrier 602-1 and non-anchor carrier 602-2. The MIB transmitted on anchor carrier 602-1 in step 302 includes an indication 1000 of non-anchor carrier 602-2 as a spectrum resource for transmitting SIB in step 304. Figure 10A , Figure 10B and Figure 10C The three examples shown in FIG. 6 differ in the allocation of NB carriers 602 - 1 and 602 - 2 for implementing NB-IoT TDD guard band deployment.

[0159] exist Figure 10A In the example of FIG. 3 , MIB-NB is transmitted on a single anchor carrier 602-1 in step 302 and indicates a SIB1-NB non-anchor carrier 602-2 (i.e., spectrum resources) allocated at the opposite end of MBB 604. The relative positions of NB carriers 602-1 and 602-2 are also referred to as "mirror deployment".

[0160] exist Figure 10B In the example of FIG. 302 , MIB-NB is transmitted on each of the two anchor carriers 602-1 according to step 302. Each MIB-NB indicates a SIB1-NB non-anchor carrier 602-2 (as a spectrum resource for SIB) allocated at the opposite end of the MBB 604 relative to the anchor carrier 602-1. This position of the NB carriers 602-1 and 602-2 relative to the center DC subcarrier 706 is also referred to as a "mirror deployment".

[0161] exist Figure 10C In the example of FIG. 3 , MIB-NB is transmitted on each of the two anchor carriers 602-1 according to step 302. Each MIB-NB indicates a SIB1-NB non-anchor carrier 602-2 (as a spectrum resource for SIB) allocated at the same side of the MBB 604 where the anchor carrier 602-1 is located. This location of the NB carriers 602-1 and 602-2 relative to each other is a "back-to-back deployment" (B2B).

[0162] Figure 11An example of MBB 604 is schematically shown, which can be implemented in any embodiment. More particularly, the low-frequency edge of system bandwidth 608 is shown in more detail. A symmetric frequency structure can be implemented at the opposite edge (i.e., the high-frequency edge of system bandwidth 608). Without limitation, the LTE channel bandwidth 609 spans 15 MHz. The LTE system bandwidth 608 includes 75 PRBs 700.

[0163] The first PRB 700 in the guard band 606 (i.e., the PRB 700 immediately following the LTE system bandwidth 608) is spaced 3 subcarriers apart in the frequency domain from the first PRB 700 used or available by MBB 604.

[0164] The channel raster 1100 of NB 602 includes a step size of 100 kHz and matches the center frequency 802 of the first PRB 700 in the guard band 606 up to a minimum offset 1102 (which is 7.5 kHz as an example).

[0165] Figures 12A to 12C An example of NB-IoT TDD guard band deployment is schematically shown, which can be implemented using any of the embodiments described herein. Without limitation, the LTE channel bandwidth 609 spans 15 MHz. The LTE system bandwidth 608 includes 75 PRBs 700.

[0166] In Figure 12A the example, MIB-NB is transmitted on a single anchor carrier 602-1 in step 302 and indicates the SIB1-NB non-anchor carrier 602-2 (i.e., the spectrum resource) allocated at the opposite end of MBB 604. The relative positions of NB carriers 602-1 and 602-2 are also referred to as "mirror deployment".

[0167] In Figure 12B the example, MIB-NB is transmitted on each of the two anchor carriers 602-1 according to step 302. Each MIB-NB indicates the SIB1-NB non-anchor carrier 602-2 (as the spectrum resource for SIB) allocated at the opposite end of MBB 604 with respect to the anchor carrier 602-1. This position of NB carriers 602-1 and 602-2 relative to the center DC subcarrier 706 is also referred to as "mirror deployment".

[0168] In Figure 12CIn the example, the MIB-NB is transmitted on each of the two anchor carriers 602-1 according to step 302. Each MIB-NB indicates the SIB1-NB non-anchor carrier 602-2 (as the spectrum resource for SIB) assigned at the same side of the MBB 604 where the anchor carrier 602-1 is located. This position of the NB carriers 602-1 and 602-2 relative to each other is a "back-to-back deployment" (B2B).

[0169] Figure 13 Schematically shows an exemplary grouping 1300 of PRBs 700 into PRB groups (RBGs) 1302 for different MBB channel bandwidths 609. The PRBs 700 are represented by indices from the middle of the MBB channel bandwidth 609.

[0170] An example position of the anchor carrier 602-1 for NB communication 502 in the RBG is shown in Figure 13 in terms of PRBs 700. Corresponding indices can be included for the indication 1000 of the spectrum resource (either the anchor carrier 602-1 or another non-anchor carrier 602-2) in the MIB-NB. Additionally, the NB carriers 602-1 and / or 602-2 can be symmetrically arranged with respect to the central DC subcarrier 706 (i.e., using the same position according to the index from the middle).

[0171] As is obvious from the example of index 10, for different MBB channel bandwidths 809, the same position of the anchor carrier according to the PRB index from the middle of the MBB channel bandwidth 609 can be on different sides of the RBG 1302.

[0172] Partially referring to FIGS. 10 to Figure 13 Describe a first embodiment of the present technology to explain implementation variants of this embodiment. The MIB-NB for NB-IoT TDD communication 502 indicates to the UE 512 whether the SIB1-NB is on the anchor carrier 602-1 or on the non-anchor carrier 602-2. This indication 1000 is also referred to as the SIB mode (e.g., SIB1-NB mode).

[0173] One bit from the spare bits in the MIB-NB (e.g., as outlined above as the starting point for implementing the MIB-NB according to this technology) can be used to indicate the SIB1-NB mode. An exemplary definition of the SIB1-NB mode can be consistent with the value of the indication 1000: "0" means transmitting the SIB1-NB on the anchor carrier 602-1 as the spectrum resource. "1" means transmitting the SIB1-NB on the non-anchor carrier 602-2 as the spectrum resource in step 304.

[0174] An exemplary format of the MIB-NB and the corresponding signal structure for NB-IoT TDD communication 502 are shown in the ASN.1 below. In this implementation variant of the first embodiment, an anchor parameter called "sib1-NB-mode-tdd" is included in the MIB-NB as indication 1000 or as part of indication 1000. For example, indication 1000 may include the anchor parameter and an extension of the existing information element (IE) operation info mode. Due to the latter IE, there will be fewer spare bits left in the MIB-NB, e.g., 9 spare bits.

[0175] A part of the exemplary MIB-NB according to the first embodiment is outlined below.

[0176]

[0177] Furthermore, the IE operation mode information in the MIB-NB provides operation mode specific information to the NB UE 512. This IE can be extended to convey operation mode-dependent SIB1-NB configurations in step 302. Those skilled in the art may note in the above ASN.1 of the MIB-NB that there are several spare bits in the IE operation mode information for some of the operation modes (e.g., for the guard band operation mode, the in-band operation mode (more particularly, the in-band operation mode where the same physical cell identifier PCI is used for both NB 602 and MBB 604), and the stand-alone mode). These spare bits can be used for SIB1-NB configurations.

[0178] The guard band mode is described for the first embodiment. 3GPP LTE defines 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz as the LTE channel bandwidth 809. NB-IoT guard band deployment (e.g., only) is possible for 5 MHz, 10 MHz, 15 MHz, and 20 MHz channel bandwidths 809. In the guard band mode, the NB-IoT carriers 602-1 and 602-2 are placed in the guard band region 606 of the LTE channel band 809.

[0179] It is possible but not necessary to place the NB-IoT carriers 602-1 and 602-2 on the LTE PRB grid. Additionally, it is preferable to place the NB-IoT carriers 602-1 and 602-2 on the LTE subcarrier grid to avoid inter-subcarrier interference. In principle, the NB-IoT carriers 602-1 and 602-2 can be placed on any subcarriers in the guard band, as long as the 180 kHz NB-IoT band fully falls within the guard band 606. Additionally, for the anchor carrier 602-1, the frequency offset from the 100 kHz channel raster must be + / -2.5 kHz or + / -7.5 kHz, otherwise the NB UE 512 may not be able to find the anchor carrier 602-1.

[0180] Since the NB-IoT carriers 602-1 and 602-2 in the guard band 606 can be deployed in so many different positions, it is difficult or impossible to signal them using only a few bits. Therefore, a limited number of candidate positions for NB-IoT deployment are proposed. Advantageous implementations for selecting these candidate positions in the guard band mode are discussed.

[0181] Generally speaking, it is beneficial to deploy NB-IoT as close as possible to the LTE carrier (i.e., as close as possible to the LTE system bandwidth 608) to reduce adjacent channel interference and simplify the implementation of network devices (e.g., base station 510), etc. For LTE channel bandwidths of 20 MHz and 10 MHz, the first PRB 700 in the guard band is exactly close enough to the 100 kHz channel raster 1100 (i.e., has an offset of less than 7.5 kHz, actually 2.5 kHz). Therefore, the first PRB 700 in the guard band 606 can be selected as the anchor carrier 602-1. Figures 10A to 10C Each of the figures schematically shows an exemplary NB-IoT TDD deployment in the guard band 606 of the LTE band 604 with a 20 MHz channel bandwidth 609.

[0182] For a channel bandwidth 609 of 15 MHz or 5 MHz, the first PRBs in the guard band are so far from the channel raster that they cannot be used as anchor carriers. The first possible anchor carrier PRB 700 in the guard band 600 is the third PRB counted from the edge of the LTE in-band 608. To reduce the frequency gap from the LTE system band 608, three empty subcarriers are added or introduced immediately after the in-band edge (e.g., left unallocated) so as to push the first PRB 700 in the guard band 606 to the channel raster 1100. After inserting 3 empty subcarriers, the shifted first PRB 700 in the guard band 600 is 7.5 kHz off the NB carrier raster 1100. Therefore, the shifted first PRB 700 can be used as the anchor carrier 602-1 for NB-IoT 602.Figure 11 An exemplary NB-IoT TDD deployment in the guard band 600 of LTE band 604 with a 15 MHz channel bandwidth 609 is shown schematically.

[0183] Based on the above analysis, for the guard band deployment of NB-IoT TDD communication 502, counting from the edge within the band, one or two anchor carriers 602-1 can be placed on the first PRB in the guard band 606. For the 15 MHz and 5 MHz cases of the channel bandwidth 609, 3 empty subcarriers can be added between the PRB grid in the in-band 608 (for the PRB 700 available for MBB 604) and the PRB grid in the guard band 606 (for the PRB 700 available for NB 602).

[0184] Following the same principle of SIB1-NB non-anchor carrier deployment, Figures 12A to 12C Different examples of the guard band deployment of NB-IoT TDD communication 502 coexisting with an LTE band 602 including a 15 MHz channel bandwidth 609 are shown schematically.

[0185] The SIB1-NB non-anchor carrier can be deployed in the second guard band PRB 700 adjacent to the anchor carrier 602-1 (e.g., as shown in each figure of Figure 12B and Figure 12C ), or on the other side of the LTE band 604 (e.g., as shown in Figure 12A ). In this document, the case where the indication 1000 in the MIB refers to the non-anchor carrier 602-2 as a spectrum resource is called "back-to-back" deployment (e.g., as shown in Figure 12C ). The case where the indication 1000 refers to the other side of the LTE band 604 is called "mirror deployment" (e.g., as shown in Figure 12A and Figure 12B ). In the mirror deployment scenario, the non-anchor carrier 602-2 for SIB1-NB can be deployed in the first guard band PRB 700, which is preferred from the perspective of network implementation complexity (e.g., as shown in Figure 12A ), or can be deployed on the second guard band PRB 700, leaving the first guard band PRB for another anchor carrier deployment (e.g., as shown in Figure 12C ).

[0186] For the UE 512 to be able to locate the SIB1-NB non-anchor carrier 602-2 which may be at the other end of the LTE band 604, the in-band bandwidth 608 in units of the number of PRBs 700 is included in the operating mode information for the guard band mode. The listed numbers of in-band bandwidth 608 shall include 25, 50, 75, and 100 in units of PRBs 700, which respectively correspond to 5, 10, 15, and 20 MHz LTE bandwidths 609.

[0187] There are different alternative implementations to provide the SIB1-NB non-anchor carrier configuration in the MIB-NB. One implementation is to extend the existing guard band IE operating mode information using any combination of the following three parameters. The first parameter, in-band bandwidth, can indicate the LTE bandwidth 608 in units of the number of PRBs. The second parameter, SIB1-NB position, can indicate on which side of the anchor carrier 602-1 the SIB1-NB carrier 602-2 is deployed in the spectrum, e.g., "lower frequency" or "higher frequency". The third parameter, SIB1-NB PRB information, can indicate on which guard band PRB 700 the SIB1-NB non-anchor carrier 602-2 is mapped, whether it is the "first" PRB or the "second" PRB.

[0188] The following ASN.1 shows an exemplary implementation of the guard band operating mode information as part of an exemplary MIB-NB according to the first embodiment.

[0189]

[0190] In another implementation, the SIB1-NB position and the SIB1-NB PRB information are jointly encoded into a 2-bit field using the following exemplary definition (referred to herein as the SIB1-NB configuration guard band).

[0191] SIB1-NB configuration guard band:

[0192] 00: Back-to-back deployment, second PRB

[0193] 01: Mirror deployment, first PRB

[0194] 10: Mirror deployment, second PRB

[0195] 11: Reserved

[0196] The following outlines an exemplary implementation of the guard band operating mode information with the SIB1-NB configuration as part of an exemplary MIB-NB according to the first embodiment.

[0197]

[0198] As can be seen in the following sections, the SIB1-NB location parameter can also be used in broadcasting the SIB1-NB configuration for in-band and stand-alone modes. Additionally, the SIB1-NB location can be promoted (e.g., implemented as a global parameter included in the IE for MIB-NB) to become a common parameter for all operating modes. Alternatively or additionally, this information can be jointly encoded with some other parameters in MIB-NB, for which exemplary implementations are given in the following sections.

[0199] Using the above anchor carrier deployment mechanism, the NB UE 512 can identify on which side of the LTE band 604 the anchor carrier 602-1 is located by looking at the channel raster offset and in-band bandwidth in the operating mode information according to the following table. A positive channel raster offset indicates an anchor carrier in the lower frequency guard band, while a negative value indicates an anchor carrier in the higher frequency guard band. Together with the signaled in-band bandwidth 608 and SIB1-NB configuration parameters, the NB UE 512 can determine the exact location of the SIB1-NB non-anchor carrier 602-2.

[0200] The following table outlines an exemplary relationship between the guard band location for the anchor carrier and the sign of the channel raster offset in the guard band deployment.

[0201]

[0202] The in-band deployment of the first embodiment is described. The NB-IoT TDD carriers 602-1 and 602-2 are deployed on the LTE PRB grid 608 to coexist with the LTE-TDD system. The NB-IoT TDD anchor carrier 602-1 can be deployed on the LTE PRB 700, and the offset of the center frequency 802 of the LTE PRB 700 from the 100 kHz channel raster 1100 is no greater than 7.5 kHz. In theory, the SIB1-NB non-anchor carrier 602-2 can be deployed in any other LTE PRB 700 except for the center PRB (e.g., the middle 6 PRBs 804) where the LTE PSS / SSS / PBCH is broadcast. Following the 3GPP Release 14 frequency structure, 5 bits are uniquely used to indicate the non-anchor PRB requirement for SIB1-NB with full deployment flexibility. If certain constraints can be imposed on the non-anchor carrier deployment (e.g., by restricting the SIB1-NB non-anchor carrier to the adjacent PRBs around the anchor carrier), fewer bits can be used.

[0203] As discussed previously, for in-band operation, it is desirable to have the anchor carrier and the non-anchor carrier in the same Physical Resource Block group (Resource Block Group, RBG) 1302. Therefore, it is preferred that the position of the non-anchor carrier 602-2 is configured, via the MIB-NB, as the Physical Resource Block 700 at the lower frequency or the higher frequency closest to the anchor carrier 602-1. This is because the anchor carrier can be on either side of the boundary of the RBG group, as Figure 13 shown in

[0204] Therefore, an additional 1 bit in the MIB-NB can indicate whether the non-anchor carrier 602-2 is the Physical Resource Block 700 at the lower frequency closest to the anchor carrier 602-1 or the Physical Resource Block 700 at the higher frequency closest to the anchor carrier 602-1. In the following example, the parameter SIB1-NB position is defined as part of the indication 1000 in the MIB-NB.

[0205]

[0206] In a variant, as mentioned above in the context of guard band deployment, the SIB1-NB position parameter can be promoted to a common parameter for all operating modes. A corresponding example is outlined in the following part of the exemplary MIB-NB.

[0207]

[0208] In a variant of the embodiment, the higher frequency Physical Resource Block 700 or the lower frequency Physical Resource Block 700 as the spectral resource for the SIB is not implemented as a binary indicator. Instead, the indication in the MIB-NB can include a step size in units of the number of Physical Resource Blocks 700, and the direction is always towards the higher (or lower) Physical Resource Block with wrap-around at the boundary of the RBG 1302.

[0209] An independent deployment of the embodiment is described. In this deployment scenario, there is no coexisting MBB (e.g., LTE-TDD) system. The NB-IoT TDD anchor carrier 602-1 can be deployed on the 100 kHz channel raster 1100 in the assigned frequency band of the NB TDD communication 502.

[0210] In 3GPP Release 13, the non-anchor carrier can be deployed on the 100 kHz channel raster in the same frequency band as the anchor carrier, which is basically the deployment principle of NB-IoT FDD.

[0211] However, if two NB-IoT carriers 602-1 and / or 602-2 are deployed in two adjacent 200 kHz channels, adjacent channel interference may become an issue. For this reason, NB-IoT channels cannot fit the same 15 kHz subcarrier grid. A comprehensive analysis of this problem can be found in 3GPP document R4-1703804 ["Channel raster for multiple independent NB-IoT carriers, source Nokia", Alcatel-Lucent Shanghai Bell, 3GPP TSG-RAN4#82-bis, Spokane, Washington, USA, April 3 - 7, 2017].

[0212] Preferably, the non-anchor carrier 602-2 is not placed exactly on the 100 kHz channel raster 1100. Instead, they are deployed with a specific frequency offset to the channel raster 1100 to achieve subcarrier grid alignment with the anchor carrier 602-1.

[0213] Regardless of which deployment principle is adopted, the SIB1-NB non-anchor carrier 602-2 can be indicated in the MIB-NB using the relative frequency offset to the anchor carrier 602-1. This relative frequency offset can be given in units of the number of 15 kHz subcarriers, or in units of the number of 180 kHz PRBs, or in units of the number of 200 kHz NB-IoT channel bandwidths.

[0214] In existing MIB-NB (e.g., for FDD), there are 5 spare bits available for this purpose. Additionally, potential extra bits for extended operation mode information (e.g., for the in-band mode as described in the previous section) can also be used. An exemplary ASN.1 for operation mode information can be defined as follows.

[0215]

[0216] In the above example, 1 bit is used as the SIB1-NB position with the same definition as other deployment modes, and 4 bits are used to indicate the absolute value of the SIB1-NB carrier frequency offset in terms of PRBs relative to the anchor carrier 602-1.

[0217] MIB-NB ASN.1 for the exemplary implementation of the first embodiment

[0218] Although different deployments have been described separately and can be implemented separately, a preferred implementation of the first embodiment uses a format or signal structure for the MIB that can be deployed in two or all three operation modes.

[0219] Summarizing the analysis given above, the following outlines the MIB-NB ASN.1 for an exemplary implementation of the first embodiment, which is used to solve the problem of indicating the spectral resources (e.g., SIB1-NB non-anchor 602-2) for NB-IoT TDD communication 502. The text marked in bold can be added or updated, starting from the definitions of 3GPP Release 14 described previously as the starting point or baseline.

[0220]

[0221] In the example above, the total size of the MIB-NB remains 34 bits, i.e., the same size as the MIB-NB for NB-IoT FDD. The operation mode information for the guard band is extended using the parameters in-band bandwidth, SIB1-NB position, and SIB1-NB PRB information. Alternatively or in combination, the operation mode information for in-band same PCI mode and in-band different PCI mode is extended using the parameter SIB1-NB position. Alternatively or in combination, the operation mode information for the stand-alone case is extended using a 5-bit parameter that specifies the SIB1-NB non-anchor carrier offset to the anchor carrier in units of the number of 180 kHz PRB bandwidths, which gives a non-anchor carrier deployment dynamic of 5.76 MHz.

[0222] Compared to the baseline, a total of 2 additional bits are used in the example above, leaving 9 spare bits in the MIB-NB for future use.

[0223] A second embodiment of the technique is described, which can be combined with the first embodiment. In the second embodiment, the indication 1000 in the MIB jointly encodes the SIB1-NB position with the previously defined SIB1-NB mode in a 2-bit field. The example is outlined as the following part of the exemplary MIB-NB.

[0224]

[0225] Note that in the example above, only 3 different values need to be signaled. Two bits give 4 different values. Therefore, for further compatibility, e.g., in 3GPP Release 15, the fourth value of the 2-bit parameter can be interpreted as the same as the first value. For example, the bit "00" can be used to indicate that SIB1-NB is transmitted only on the anchor carrier, "01" can be used to indicate that SIB1-NB is transmitted on the non-anchor carrier 602-2, which is the PRB of the lower frequency closest to the anchor carrier 602-1, and "10" can be used to indicate that SIB1-NB is transmitted on the non-anchor carrier 602-2, which is the PRB of the higher frequency closest to the anchor carrier 602-1. The bit "11" can have the same meaning as "00", "01", or "10".

[0226] The following part of another exemplary MIB-NB uses 4 different values.

[0227]

[0228] In the above example, the MIB indicates the subframe for SIB1-NB transmission on the anchor carrier, which can be beneficial from the perspective of interference management. Although subframe #0 and subframe #4 are used as examples above, other downlink subframes can also be used and configured in the MIB.

[0229] In addition, the field sib1-NB-mode-tdd can be interpreted differently for different operating modes. For the in-band case, the direct interpretation is whether the non-anchor carrier 602-2 is used for SIB1-NB transmission, and if it is used, whether the non-anchor carrier 602-2 is the PRB on the lower frequency side closest to the anchor carrier 602-1 or the PRB on the higher frequency side closest to the anchor carrier 602-1.

[0230] When in the stand-alone mode, the interpretation can be whether the non-anchor carrier 602-2 is used for SIB1-NB transmission, and if it is used, whether the non-anchor carrier 602-2 is on the lower frequency side or the higher frequency side of the anchor carrier 602-1. The exact position of the non-anchor carrier can be signaled by using, for example, sib1-NB-offsetStandalone-tdd according to the first embodiment, without having an offset symbol (+ or -) (given by the SIB1-NB-Position field in the operating mode information for the in-band mode). This is because the + / − symbol of the offset has already been indicated by a 2-bit field.

[0231] When it comes to the guard band, the field sib1-NB-mode-tdd can be used to replace the SIB1-NB-Position field in the operating mode information for the guard band mode according to the first embodiment. This is because the field sib1-NB-mode-tdd can indicate whether the non-anchor carrier 602-2 is adjacent to the anchor carrier 602-1 (i.e., back-to-back) or on the other frequency band edge (i.e., mirrored). It is worth noting that there can be only one anchor carrier 602-1 in the guard band on each side or edge of the MBB band 604, and the channel raster 1100 of the anchor carrier 602-1 can be used by the NB UE 512 to identify on which side of the frequency band edge the anchor carrier 602-1 resides. In some of the bandwidth 608, the anchor carrier 602-1 is not on the PRB grid. However, the NB UE 512 can use the anchor carrier 602-1 as a reference to determine the position of the non-anchor carrier 602-2 carrying SIB1-NB.

[0232] For example, in the guard band mode, the 2-bit field sib1-NB-mode-tdd indicates whether SIB1-NB is transmitted on the non-anchor carrier 602-2, and if so, together with the channel raster 1100 of the anchor carrier 602-1, it can indicate whether the non-anchor carrier 602-2 is at the same frequency band edge or at another (e.g., opposite) frequency band edge. The PRB position and MBB bandwidth 608 of the LTE system can be signaled in the same manner as in the first embodiment.

[0233] The following outlines a part of another exemplary implementation of MIB-NB with the help of ASN.1.

[0234]

[0235] In the above example, the SIB1-NB position is treated as a common parameter for all operation modes and is jointly encoded into the SIB1-NB mode. Similar to the first example, two additional bits are used in the above example compared to the MIB-NB for NB-IoT FDD in Release 14.

[0236] Any stand-alone deployment can determine the spectral resources (i.e., the non-anchor carrier 602-2) for SIB based on the field sib1-NB-mode-tdd. Figure 14A and Figure 14B respectively schematically show the cases of the third value and the second value of this field signaled by the MIB in step 302. For example, SIB1 non-anchor 602-2 can be indicated by setting the parameter higher_freq or lower_freq in the first embodiment or by setting the parameter non-anchor_higher_freq or non-anchor_lower_freq in the second embodiment.

[0237] In a third embodiment that can be combined with the first or second embodiment, a finite set of possible PRBs 700 (i.e., candidates) for SIB1-NB is defined (e.g., one set for each of in-band deployment, guard band deployment, and stand-alone deployment). The indication 1000 in the MIB-NB can only indicate which one of the possible PRB candidates is currently in use.

[0238] As an example, for guard band operation, there can be 3 possible PRBs 700 for the non-anchor carrier 602-2 to transmit SIB1-NB in the same guard band 606, such that it is not necessary to know the LTE bandwidth, and the indication 1000 in the MIB-NB can only indicate which one of the following applies:

[0239] MIB indication 1000 Meaning of the value 00 SIB1-NB on the anchor carrier 01 SIB1-NB on PRB candidate 1 10 SIB1-NB on PRB candidate 2 11 SIB1-NB on PRB candidate 3

[0240] In a fourth embodiment that can be combined with any of the embodiments or implementations described herein, the SIB1-NB non-anchor carrier can be predefined with reference to an anchor carrier. For example, the position of the SIB1-NB non-anchor 602-2 can be fixed (e.g., predefined or hard-coded) to the adjacent higher frequency side of the anchor carrier 602-1. One bit in the MIB indicates the presence of SIB1-NB on the non-anchor carrier 602-2. Once the UE 512 receives this notification, it detects the SIB1-NB non-anchor carrier 602-2 on the adjacent higher frequency side.

[0241] The following outlines a portion of the corresponding exemplary MIB-NB with the aid of the following ASN.1

[0242]

[0243] The fourth embodiment uses a minimum number of bits to signal an indication 1000 as to whether SIB1-NB is transmitted on the non-anchor carrier 602-2. Then the eNB implementation is responsible for ensuring proper deployment to minimize the fragmentation of the RBG.

[0244] Any of the above embodiments and implementations can be an extended embodiment for system information other than SIB1-NB. Each of the above 4 embodiments can implement selective signaling of SIB1-NB on the non-anchor carrier 602-2. The same principle can be extended to the signaling of other system information (SI). For example, an SI message containing all other SIBs can be scheduled on a non-anchor carrier.

[0245] The MIB-NB is transmitted on the same NB-IoT anchor carrier 602-1 that is also used for NPSS and / or NSSS. A single NB-IoT non-anchor carrier (i.e., other than the anchor carrier 602-1) is used for any SIB other than SIB1-NB. The single NB-IoT non-anchor carrier for SIBx is in the PRB 700 indicated by SIB1-NB, where x is an integer greater than 1. Optionally, in a radio layer 2 (RAN2) implementation, the signaling can be omitted if SIBx is on the anchor carrier 602-1.

[0246] In an optional extension of any embodiment, the method of indicating the non-anchor 602-2 on which SIB1-NB is transmitted is also reused to indicate the non-anchor carrier on which an SI message (i.e., other SIB “SIBx”) is transmitted. The SI message is scheduled (i.e., indicated) by the SIB1-NB transmitted in step 304. The following shows a corresponding example for SIB1-NB with the aid of ASN.1. Any subset of the bolded features can be implemented (e.g., independent of the context not printed in bold type).

[0247]

[0248] Figure 15 A schematic block diagram showing an embodiment of apparatus 100 is presented. Apparatus 100 includes one or more processors 1504 for performing method 200 and a memory 1506 coupled to processor 1504. For example, memory 1506 may be encoded with instructions for implementing at least one of modules 102 and 104.

[0249] One or more processors 1504 may be one or more combinations of a microprocessor, a controller, a microcontroller, a central processing unit, a digital signal processor, an application specific integrated circuit, a field programmable gate array, or any other suitable computing device, resource, or a combination of hardware, microcode, and / or encoded logic operable to provide base station or RAN functionality either alone or in combination with other components of apparatus 100 such as memory 1506. For example, one or more processors 1504 may execute instructions stored in memory 1506. Such functionality may include providing the various features and steps discussed herein, including any of the benefits disclosed herein. The phrase "the apparatus is operable to perform an action" may mean that apparatus 100 is configured to perform the action.

[0250] As Figure 15 schematically illustrated, apparatus 100 may be embodied by a base station 510 of, for example, a RAN. Base station 510 includes a radio interface 1502 coupled to apparatus 100 for radio communication with one or more radio devices.

[0251] In a variant, for example, as Figure 16 schematically illustrated, the functionality of apparatus 100 is provided by a core network linked to the RAN or a node of the RAN. That is, the node performs method 200. The functionality of apparatus 100 is provided to base station 510 by the node, for example, via interface 1502 or a dedicated wired or wireless interface.

[0252] Figure 17 A schematic block diagram showing an embodiment of apparatus 200 is presented. Apparatus 200 includes one or more processors 1704 for performing method 200 and a memory 1706 coupled to processor 1704. For example, memory 1706 may be encoded with instructions for implementing at least one of modules 102 and 104.

[0253] One or more processors 1704 can be one or more of a microprocessor, a controller, a microcontroller, a central processing unit, a digital signal processor, an application specific integrated circuit, a field programmable gate array, or any other suitable computing device, resource, or a combination of hardware, microcode, and / or coded logic operable to provide base station or RAN functionality alone or in combination with other components of device 200, such as memory 1706. For example, one or more processors 1704 can execute instructions stored in memory 1706. Such functionality can include providing the various features and steps discussed herein, including any of the benefits disclosed herein. The phrase "the device is operable to perform an action" can mean that the device 100 is configured to perform the action.

[0254] As Figure 17 schematically illustrated, device 200 can be embodied by radio device 512. Radio device 512 includes a radio interface 1702 coupled to device 200 for radio communication with a base station of the RAN and / or one or more radio devices.

[0255] In a variant, for example, as Figure 18 schematically illustrated, the functionality of device 200 is provided by a terminal linked to radio device 512. That is, the terminal executes method 200. The functionality of device 200 is provided to radio device 512 by the terminal, for example, via interface 1702 or a dedicated wired or wireless interface.

[0256] From the above description, it has become apparent that embodiments of the technology enable a radio device (e.g., a UE) to identify SIB1-NB non-anchor carriers in an NB-IoT TDD system using only a few bits broadcast in the MIB-NB, which ensures that the NB-IoT TDD system operates effectively and coexists with LTE-TDD.

[0257] Candidate locations for NB-IoT TDD guard band deployment can be positioned as close as possible to the LTE carrier to reduce adjacent channel interference and simplify the implementation of network equipment.

[0258] The technology can also be adopted in some other radio access systems where similar challenges arise.

[0259] From the foregoing description, many advantages of the present invention will be fully understood, and it will be apparent that various changes can be made in the form, construction, and arrangement of the units and devices without departing from the scope of the present invention and / or sacrificing all of its advantages. Since the present invention is capable of being varied in many ways, it will be recognized that the present invention should be limited only by the scope of the appended claims.

Claims

1. A method (300) for transmitting system information for narrowband NB time division duplex TDD communication (502) in a radio access network RAN (500), the method comprising or triggering the following steps: Transmitting (302) a master information block MIB on an anchor carrier (602-1) of the TDD communication (502) in the RAN (500), the MIB indicating spectral resources (602-1; 602-2) of system information blocks SIB allocated to the TDD communication (502) in the RAN (500); and Transmitting (304) the SIB on the spectral resources (602-1; 602-2) indicated in the MIB, wherein the MIB indicates whether the spectral resources (602-1; 602-2) are on the anchor carrier (602-1) or on a non-anchor carrier other than the anchor carrier (602-1), and wherein the MIB further indicates an operation mode, the operation mode indicating in-band NB deployment, guard band NB deployment, or stand-alone NB deployment, and wherein for each of the in-band operation mode and the stand-alone operation mode, the MIB indicates whether the spectral resources (602-1; 602-2) for transmitting the SIB are arranged in physical resource blocks PRB (700) adjacent to the lower frequency edge of the PRB (700) used by the anchor carrier (602-1) or in PRB (700) adjacent to the higher frequency edge of the PRB (700) used by the anchor carrier (602-1).

2. The method according to claim 1, wherein the MIB includes at least one parameter value indicating the spectral resources (602-1; 602-2).

3. The method according to claim 1 or 2, wherein the MIB indicates the spectral resources (602-1; 602-2) in terms of physical resource blocks PRB (700).

4. The method according to claim 1 or 2, further comprising or triggering the following steps: Transmitting an initial synchronization signal on the anchor carrier (602-1) for the TDD communication (502) in the RAN (500).

5. The method according to claim 1 or 2, wherein transmissions on the anchor carrier (602-1) are managed by an uplink-downlink configuration (900) of the TDD communication (502) in the RAN (500).

6. The method according to claim 5, further comprising or triggering the following steps: Transmit and receive (306) payload data selectively on an anchor channel according to the uplink-downlink configuration of the TDD communication (502) in the RAN (500).

7. The method according to claim 1, wherein the RAN (500) further provides radio access to a mobile broadband MBB device (514) for MBB communication (504) in the MBB system bandwidth of the RAN (500), and the NB (602) used by the NB communication (502) is deployed within the MBB system bandwidth (608) or in a guard band (606) of the MBB system bandwidth (608).

8. The method according to claim 7, wherein the NB system bandwidth covers at least one of the anchor carrier (602-1) and the non-anchor carrier (602-2).

9. The method according to claim 7 or 8, wherein PRBs (700) for the MBB communication (504) are arranged in the frequency domain according to a PRB scheme, and the anchor carrier (602-1) for the NB communication (502) is arranged in the frequency domain according to a carrier grid (1100).

10. The method according to claim 9, wherein the anchor carrier (602-1) uses PRBs (700) according to the PRB scheme, and the offset between the center frequency of the PRB (700) and the carriers of the carrier grid is equal to or less than 7.5 kHz or half of the subcarrier spacing.

11. The method according to claim 10, wherein the non-anchor carrier (602-2) uses another PRB (700) of the PRBs (700) immediately following the anchor carrier (602-1) according to the PRB scheme.

12. The method according to claim 7 or 8, wherein at least one of the anchor carrier (602-1) and the non-anchor carrier (602-2) of the NB communication (502) is located in one or more guard bands of the MBB system bandwidth.

13. The method according to claim 7 or 8, wherein the MIB indicates whether the anchor carrier (602-1) and the non-anchor carrier (602-2) are located in the same guard band of the MBB system bandwidth or in opposite guard bands of the MBB system bandwidth.

14. The method according to claim 7 or 8, wherein the anchor carrier (602-1) is closer to the frequency edge of the MBB system bandwidth than the non-anchor carrier (602-2), or is equal to the frequency edge of the MBB system bandwidth.

15. The method according to claim 7 or 8, wherein the anchor carrier (602-1) is closer to the MBB carrier frequency than the non-anchor carrier (602-2), or the anchor carrier (602-1) and the non-anchor carrier (602-2) are symmetrically arranged with respect to the MBB carrier frequency.

16. The method according to claim 7 or 8, wherein the MIB indicates whether the non-anchor carrier (602-2) for transmitting the SIB is at the guard band (606) at the lower frequency edge of the MBB system bandwidth or at the guard band (606) at the higher frequency edge of the MBB system bandwidth.

17. The method according to claim 7 or 8, wherein at least one of the anchor carrier (602-1) and the non-anchor carrier (602-2) of the NB communication (502) is within the MBB system bandwidth.

18. The method according to claim 7 or 8, wherein at least one of the spectrum resources (602-1; 602-2) for transmitting the SIB of the NB communication (502) and the anchor carrier (602-1) is within the MBB system bandwidth.

19. The method according to claim 1, 2, 7 or 8, wherein the MIB indicates the subframe for transmitting the SIB on the anchor carrier (602-1).

20. A method for receiving system information for narrowband NB time division duplex TDD communication (502) in a radio access network RAN (500), the method comprising or triggering the following steps: Receiving a master information block MIB on an anchor carrier (602-1) of the TDD communication (502) in the RAN (500), the MIB indicating the spectrum resources (602-1; 602-2) of the system information block SIB allocated to the TDD communication (502) in the RAN (500); and Receiving the SIB on the spectrum resources (602-1; 602-2) indicated in the MIB, wherein the MIB indicates whether the spectrum resources (602-1; 602-2) are on the anchor carrier (602-1) or on a non-anchor carrier other than the anchor carrier (602-1), and The MIB further indicates an operation mode, the operation mode indicating in-band NB deployment, guard band NB deployment, or stand-alone NB deployment, and for each of the in-band operation mode and the stand-alone operation mode, the MIB indicates whether the spectrum resources (602-1; 602-2) for transmitting the SIB are arranged in PRBs (700) adjacent to the lower frequency edge of the physical resource blocks PRBs (700) used by the anchor carrier (602-1) or in PRBs (700) adjacent to the higher frequency edge of the PRBs (700) used by the anchor carrier (602-1).

21. The method according to claim 20, further comprising a feature or step as claimed in any one of claims 2 to 19, or a feature or step corresponding to any one of claims 2 to 19.

22. A computer program product comprising program code portions for performing the steps as claimed in any one of claims 1 to 21 when the computer program product is executed on one or more computing devices (1504; 1704).

23. The computer program product according to claim 22, stored on a computer-readable recording medium (1506; 1706).

24. An apparatus (100) for transmitting system information for narrowband NB time division duplex TDD communication (502) in a radio access network RAN (500), the apparatus (100) comprising at least one processor (1504) and a memory (1506), the memory (1506) comprising instructions executable by the at least one processor (1504), whereby the apparatus (100) operates to: Transmit a master information block MIB on an anchor carrier (602-1) of the TDD communication (502) in the RAN (500), the MIB indicating spectrum resources (602-1; 602-2) of a system information block SIB allocated to the TDD communication (502) in the RAN (500); and Transmit the SIB on the spectrum resources (602-1; 602-2) indicated in the MIB, wherein the MIB indicates whether the spectrum resources (602-1; 602-2) are on the anchor carrier (602-1) or on a non-anchor carrier other than the anchor carrier (602-1), and Wherein the MIB further indicates an operating mode, the operating mode indicating in-band NB deployment, guard band NB deployment, or stand-alone NB deployment, and wherein for each of the in-band operating mode and the stand-alone operating mode, the MIB indicates whether the spectral resources (602-1; 602-2) for transmitting the SIB are arranged in PRBs (700) adjacent to the lower frequency edge of the physical resource blocks PRBs (700) used by the anchor carrier (602-1) or in PRBs (700) adjacent to the higher frequency edge of the PRBs (700) used by the anchor carrier (602-1).

25. The apparatus according to claim 24, further operative to perform the steps of any one of claims 2 to 19.

26. An apparatus (200) for receiving system information for narrowband NB time division duplex TDD communication (502) in a radio access network RAN (500), the apparatus (200) comprising at least one processor (1704) and a memory (1706), the memory (1706) including instructions executable by the at least one processor (1704), whereby the apparatus (200) is operative to: Receive a master information block MIB on an anchor carrier (602-1) of the TDD communication (502) in the RAN (500), the MIB indicating spectral resources (602-1; 602-2) of a system information block SIB allocated to the TDD communication (502) in the RAN (500); and Receive the SIB on the spectral resources (602-1; 602-2) indicated in the MIB, wherein the MIB indicates whether the spectral resources (602-1; 602-2) are on the anchor carrier (602-1) or on a non-anchor carrier other than the anchor carrier (602-1), and Wherein the MIB further indicates an operating mode, the operating mode indicating in-band NB deployment, guard band NB deployment, or stand-alone NB deployment, and wherein for each of the in-band operating mode and the stand-alone operating mode, the MIB indicates whether the spectral resources (602-1; 602-2) for transmitting the SIB are arranged in PRBs (700) adjacent to the lower frequency edge of the physical resource blocks PRBs (700) used by the anchor carrier (602-1) or in PRBs (700) adjacent to the higher frequency edge of the PRBs (700) used by the anchor carrier (602-1).

27. The apparatus according to claim 26, further operative to perform the steps of any one of claims 2 to 19, or steps corresponding to any one of claims 2 to 19.

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