Patent Description:
The following abbreviations are herewith defined, at least some of which are referred to within the following description: Third Generation Partnership Project ("3GPP"), Downlink ("DL"), Evolved Node B ("eNB"), European Telecommunications Standards Institute ("ETSI"), Frequency Division Duplex ("FDD"), Frequency Division Multiple Access ("FDMA"), Internet-of-Things ("IoT"), Narrowband Internet-of-Things ("NB-IoT" or "NBIoT"), Long Term Evolution ("LTE"), Multiple Access ("MA"), Narrowband ("NB"), Narrowband Physical Downlink Shared Channel ("NPDSCH" or "NB-PDSH"), Narrowband Physical Broadcast Channel ("NPBCH" or "NB-PBCH"), Narrowband Physical Downlink Control Channel ("NPDCCH", or "NB-PDCCH"), Next Generation Node B ("gNB"), Narrowband Primary Synchronization Signal ("NPSS"), Narrowband Secondary Synchronization Signal ("NSSS"), Orthogonal Frequency Division Multiplexing ("OFDM"), Physical Resource Block ("PRB"), Radio Resource Control ("RRC"), Reference Signal ("RS"), Single Carrier Frequency Division Multiple Access ("SC-FDMA"), System Information ("SI"), System Information Block ("SIB"), System Information Block Type1-NB ("NB-SIB1"), Time-Division Duplex ("TDD"), Time Division Multiplex ("TDM"), User Entity/Equipment (Mobile Terminal) ("UE"), Uplink ("UL"), Universal Mobile Telecommunications System ("UMTS"), and Worldwide Interoperability for Microwave Access ("WiMAX").

A downlink narrowband physical channel corresponds to a set of resource elements carrying information originating from higher layers. The following downlink physical channels are defined:.

The transmitted signal on one antenna port in each slot is described by a resource grid of size one resource block. Only Δf = <NUM> is supported.

For NPDSCH carrying SystemInformationBlockType1-NB (NB-SIB1) and SI-messages, the UE shall decode NPDSCH according to the transmission scheme: "if the number of NPBCH antenna ports is one, Single-antenna port, port <NUM> is used, otherwise Transmit diversity".

For NB-IoT (Narrowband Internet-of-Things) TDD downlink, NPSS/NSSS/NB-PBCH are transmitted on the anchor carrier.

NPSS is transmitted on subframe #<NUM> in every radio frame.

NSSS is transmitted on subframe #<NUM> in every even-numbered radio frame.

NB-PBCH is in subframe <NUM> in every radio frame on the same carrier as NPSS/NSSS.

Due to the limited downlink resource for TDD of NB-IoT, NB-SIB1 cannot always be transmitted on an anchor carrier.

<NPL>, discloses anchor and non-anchor carriers located in guard band and their contents.

Methods and apparatuses for indicating a frequency offset of a non-anchor carrier are disclosed.

Understanding that these drawings depict only some embodiments, and are not therefore to be considered to be limiting of scope, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:.

Accordingly, embodiments may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may generally all be referred to herein as a "circuit", "module" or "system". Furthermore, embodiments may take the form of a program product embodied in one or more computer readable storage devices storing machine-readable code, computer readable code, and/or program code, referred to hereafter as "code".

Certain functional units described in this specification may be labeled as "modules", in order to more particularly emphasize their independent implementation.

This operational data may be collected as a single data set, or may be distributed over different locations including over different computer readable storage devices.

The storage device may be, for example, but need not necessarily be, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

A non-exhaustive list of more specific examples of the storage device would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, random access memory ("RAM"), read-only memory ("ROM"), erasable programmable read-only memory ("EPROM" or "Flash Memory"), portable compact disc read-only memory ("CD-ROM"), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Code for carrying out operations for embodiments may be any number of lines and may be written in any combination of one or more programming languages including an object-oriented programming language such as Python, Ruby, Java, Smalltalk, C++, or the like, and conventional procedural programming languages, such as the "C" programming language, or the like, and/or machine languages such as assembly languages. The code may be executed entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the very last scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network ("LAN") or a wide area network ("WAN"), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid any obscuring of aspects of an embodiment.

This code may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which are executed via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the schematic flowchart diagrams and/or schematic block diagrams for the block or blocks.

The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices, to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function/act specified in the schematic flowchart diagrams and/or schematic block diagrams block or blocks.

The code may also be loaded onto a computer, other programmable data processing apparatus, or other devices, to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the code executed on the computer or other programmable apparatus provides processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

<FIG> depicts an embodiment of a wireless communication system <NUM> for indicating the frequency offset of the non-anchor carrier. In one embodiment, the wireless communication system <NUM> includes remote units <NUM> and base units <NUM>. Even though a specific number of remote units <NUM> and base units <NUM> are depicted in <FIG>, one skilled in the art will recognize that any number of remote units <NUM> and base units <NUM> may be included in the wireless communication system <NUM>.

The remote units <NUM> may be referred to as subscriber units, mobiles, mobile stations, users, terminals, mobile terminals, fixed terminals, subscriber stations, UE, user terminals, a device, or by other terminology used in the art. Moreover, the remote units <NUM> may be a terminal of an IoT (Internet-of-Things).

The base units <NUM> may be distributed over a geographic region. In certain embodiments, a base unit <NUM> may also be referred to as an access point, an access terminal, a base, a base station, a Node-B, an eNB, a gNB, a Home Node-B, a relay node, a device, or by any other terminology used in the art. The base units <NUM> are generally part of a radio access network that includes one or more controllers communicably coupled to one or more corresponding base units <NUM>.

In one implementation, the wireless communication system <NUM> is compliant with the LTE of the 3GPP protocol, wherein the base unit <NUM> transmits using an OFDM modulation scheme on the DL and the remote units <NUM> transmit on the UL using a SC-FDMA scheme or an OFDM scheme. More generally, however, the wireless communication system <NUM> may implement some other open or proprietary communication protocol, for example, WiMAX, among other protocols.

In various embodiments, a base unit <NUM> may transmit a broadcast signal on an anchor carrier and transmit system information on a non-anchor carrier, wherein the broadcast signal includes a frequency offset of the non-anchor carrier to the anchor carrier.

In certain embodiments, a remote unit <NUM> may receive the broadcast signal on the anchor carrier and receive the system information on the non-anchor carrier.

<FIG> depicts one embodiment of an apparatus <NUM> that may be used for receiving the broadcast signal and the system information. The apparatus <NUM> includes one embodiment of the remote unit <NUM>. Furthermore, the remote unit <NUM> may include a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM>, and a receiver <NUM>. In some embodiments, the input device <NUM> and the display <NUM> are combined into a single device, such as a touchscreen. In certain embodiments, the remote unit <NUM> may not include any input device <NUM> and/or display <NUM>. In various embodiments, the remote unit <NUM> may include at least one of the processor <NUM>, the memory <NUM>, the transmitter <NUM> and the receiver <NUM>, and may not include the input device <NUM> and/or the display <NUM>.

In some embodiments, the memory <NUM> stores data relating to system parameters.

As another, non-limiting example, the display <NUM> may include a wearable display such as a smart watch, smart glasses, a heads-up display, or the like.

The transmitter <NUM> is used to provide UL communication signals to the base unit <NUM> and the receiver <NUM> is used to receive DL communication signals from the base unit <NUM>. In various embodiments, the receiver <NUM> may be used to receive the broadcast signal one the anchor carrier and the system information on the non-anchor carrier, wherein the broadcast signal includes a frequency offset of the non-anchor carrier to the anchor carrier.

<FIG> depicts one embodiment of an apparatus <NUM> that may be used for indicating a frequency offset of the non-anchor carrier. The apparatus <NUM> includes one embodiment of the base unit <NUM>. Furthermore, the base unit <NUM> may include at least one of a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM> and a receiver <NUM>. As may be appreciated, the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> may be substantially similar to the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> of the remote unit <NUM>, respectively.

In various embodiments, the transmitter <NUM> is used to transmit a broadcast signal on an anchor carrier and transmit a system information on a non-anchor carrier, wherein the broadcast signal includes a frequency offset of the non-anchor carrier to the anchor carrier. Although only one transmitter <NUM> and one receiver <NUM> are illustrated, the base unit <NUM> may have any suitable number of transmitters <NUM> and receivers <NUM>.

<FIG> depicts that the system information NB-SIB1 can be transmitted in non-anchor carriers. As shown in <FIG>, the NB-PBCH is transmitted on subframe #<NUM> in every radio frame of the anchor carrier; the NPSS is transmitted on subframe #<NUM> in every radio frame of the anchor carrier; the NSSS is transmitted on subframe #<NUM> in every even-numbered radio frame. On the other hand, due to the limited downlink resource for TDD, the NB-SIB1, which is a system information, cannot be always transmitted on the anchor carrier. As shown in <FIG>, the NB-SIB1 may be transmitted on a non-anchor carrier.

The anchor carrier is the carrier carrying at least synchronization signal and broadcast signal. The remote unit is always able to identify the anchor carrier and receive signals transmitted on the anchor carrier. However, the frequency offset of the non-anchor carrier is necessary to be indicated so that the remote unit knows the frequency of the non-anchor carrier in order to obtain the system information NB-SIB1.

The NB-SIB1 can be transmitted either in the anchor carrier or the non-anchor carrier. Whether the NB-SIB1 is transmitted on the anchor carrier or the non-anchor carrier is indicated by a NB-MIB. The NB-MIB is a broadcast signal transmitted on the anchor carrier.

The remote unit, upon receiving the broadcast signal transmitted on the anchor carrier, extracts the NB-MIB in order to know the frequency offset of the non-anchor carrier on which the NB-SIB1 is transmitted.

Three operation modes are supported for TDD NB-IoT: standalone, guard band and in-band. In the in-band operation mode, a resource block in a LTE carrier is used as the carrier. In the guard band operation mode, the resource blocks that are not used in the edge protection bands of the LTE are used as the carrier. In the standalone operation mode, a refarming GSM band with a width of <NUM> is always used as the carrier.

In different operation modes, the indications of the frequency offset of the non-anchor carrier in the NB-MIB are different.

<FIG> depicts one embodiment of non-anchor carrier frequency offset indication in the in-band operation mode. In the in-band operation mode, one PRB in LTE carrier is configured as the anchor carrier. The other PRBs in LTE carrier may be configured as the non-anchor carriers. Preferably, the adjacent PRBs of the PRB which is the anchor carrier are configured as the non-anchor carrier. As depicted in <FIG>, for in a <NUM> LTE systems, if PRB#<NUM> is configured as a NBIoT anchor carrier, PRB#<NUM> or PRB#<NUM> may be configured as the non-anchor carrier. Preferably, the resource block group (RBG) in legacy LTE is not fragmented. In the example of <FIG>, if PRB#<NUM> is configured as the anchor carrier, it is better to configure the non-anchor carrier in PRB#<NUM> instead of PRB#<NUM>. As another example, if PRB#<NUM> is configured as the anchor carrier, it is better to configure the non-anchor carrier in PRB#<NUM> instead of PRB#<NUM>.

To indicate whether the lower frequency carrier (PRB) or the higher frequency carrier (PRB) is configured as the non-anchor carrier, one bit is necessary to be included in the NB-MIB. In addition, another bit is preferably included in the NB-MIB to distinguish whether the carrier for transmitting the NB-SIB1 is the anchor carrier or the non-anchor carrier.

Table <NUM> provides a detailed solution:.

"<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> of the anchor carrier. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> of the anchor carrier. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> (in the condition that the cell ID is even) or subframe #<NUM> (in the condition that the cell ID is odd) of the non-anchor carrier. The non-anchor carrier is <NUM> higher than the anchor carrier (the non-anchor carrier is the adjacent higher PRB in LTE to PRB which is the anchor carrier), i.e. the center frequency of the non-anchor carrier - the center frequency of the anchor carrier = <NUM>. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> (in the condition that the cell ID is even) or subframe #<NUM> (in the condition that the cell ID is odd) of the non-anchor carrier. The non-anchor carrier is <NUM> lower than the anchor carrier (the non-anchor carrier is the adjacent lower PRB in LTE to PRB which is the anchor carrier), i.e. the center frequency of the anchor carrier - the center frequency of the non-anchor carrier = <NUM>.

In summary, a total of two (<NUM>) bits are necessary in the NB-MIB to indicate (<NUM>) whether the NB-SIB1 is transmitted on the anchor carrier or the non-anchor carrier and (<NUM>) the non-anchor carrier is higher or lower than the anchor carrier, i.e. there is a frequency offset X between the non-anchor carrier and the anchor carrier, wherein the frequency offset X is a predefined, fixed, or pre-configured positive value.

<FIG> depicts one embodiment of the non-anchor carrier frequency offset indication in the standalone operation mode.

As depicted in <FIG>, in the standalone operation mode, the channel band width is <NUM>. Therefore, each of the anchor and non-anchor carriers is within the channel band. In the standalone operation mode, the anchor and non-anchor carriers are not adjacent PRBs with <NUM>.

In the standalone operation mode, the anchor carrier should meet the <NUM> channel raster requirement. On the other hand, there is no <NUM> channel raster requirement for non-anchor carriers. Therefore, in addition to a first bit for indicating whether the carrier is the anchor carrier or the non-anchor carrier and a second bit for indicating whether a lower frequency carrier or a higher frequency carrier is configured as the non-anchor carrier, additional bits (for example, two bits) are necessary to indicate an absolute frequency offset of the non-anchor carrier to the anchor carrier. The absolute frequency offset should be positive. The absolute frequency offset may be calculated by an absolute number of subcarriers (<NUM>) from the center of non-anchor carrier to the center of the anchor carrier, or by an absolute number of PRBs (<NUM>) from the center of the non-anchor carrier to the center of the anchor carrier.

Tables <NUM> and <NUM> provide a detailed solution:.

To be compatible with the in-band operation mode, Table <NUM> is substantially the same as Table <NUM>. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> of the anchor carrier. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> of the anchor carrier. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> (in the condition that the cell ID is even) or subframe #<NUM> (in the condition that the cell ID is odd) of the non-anchor carrier. The non-anchor carrier is higher than the anchor carrier by X. the center frequency of the non-anchor carrier - the center frequency of the anchor carrier = X (X is an absolute number of subcarriers (<NUM>) in this embodiment). "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> (in the condition that the cell ID is even) or subframe #<NUM> (in the condition that the cell ID is odd) of the non-anchor carrier. The non-anchor carrier is lower than the anchor carrier by X. the center frequency of the anchor carrier - the center frequency of the non-anchor carrier = X (X is an absolute number of subcarriers (<NUM>) in this embodiment).

Table <NUM> indicates the value of X. X is determined by an extra indication in the NB-MIB. "<NUM>" means that X = <NUM> subcarriers (<NUM>). "<NUM>" means that X = <NUM> subcarriers (<NUM>). "<NUM>" means that X = <NUM> subcarriers (<NUM>). "<NUM>" is reserved.

Therefore, a total of four (<NUM>) bits is used for indication. For example, the indication <NUM> means that the carrier is the non-anchor carrier that is <NUM> subcarriers (or <NUM>) higher than the anchor carrier.

It can be seen that some combinations of <NUM> bits are not used as described above (in other words, they have the same meaning). For example, all of <NUM>, <NUM>, <NUM> and <NUM> may represent that the carrier is the anchor carrier and the subframe is <NUM>.

Another solution is proposed in Table <NUM>.

In the solution indicated in the Tables <NUM> and <NUM>, the frequency offset of the non-anchor carrier to the anchor carrier is represented by (<NUM>) whether the non-anchor carrier has a higher or lower frequency than the anchor carrier and (<NUM>) an absolute frequency offset value of the non-anchor carrier to the anchor carrier. On the other hand, in the solution indicated in Table <NUM>, the frequency offset of the non-anchor carrier to the anchor carrier is represented by a relative frequency offset, which may be a positive or a negative value. For example, as shown in Table <NUM>, "<NUM>" represents that the non-anchor carrier is <NUM> subcarriers offset from the anchor carrier, i.e. the center frequency of the non-anchor carrier - the center frequency of the anchor carrier = <NUM> subcarriers (a positive value). "<NUM>" represents that the non-anchor carrier is -<NUM> subcarriers offset from the anchor carrier, i.e. the center frequency of the non-anchor carrier - the center frequency of the anchor carrier = -<NUM> subcarriers (a negative value). Similarly, "<NUM>", "<NUM>", "<NUM>" and "<NUM>" represent that the non-anchor carrier is, respectively, <NUM> subcarriers, -<NUM> subcarriers, <NUM> subcarriers and -<NUM> subcarriers offset from the anchor carrier. Moreover, it can be seen that the relative frequency offset(s) of the non-anchor carrier to the anchor carrier, i.e. positive and negative values, are symmetrical to zero, e.g. <NUM> subcarriers and -<NUM> subcarriers are symmetrical to zero, <NUM> subcarriers and -<NUM> subcarriers are symmetrical to zero, and <NUM> subcarriers and -<NUM> subcarriers are symmetrical to zero.

<FIG> depicts an example of NB-IoT anchor carrier deployment for the guard band. The guard band NB-IoT deployment may be different for different operators/vendors. The band(s), especially the detailed numbers of the frequencies shown in <FIG>, are only for examples.

As shown in <FIG>, for <NUM> and <NUM> LTE system bandwidths, anchor carriers are potentially placed on the first PRB in the guard-band, counting from the edge of the in-band. In consideration of the <NUM> channel raster requirement, there is only one potential anchor carrier available for each side of guard band.

The <NUM> channel raster requirement means that the center frequency of the anchor carrier should be a multiple of <NUM>. In the guard band operation mode, the center frequency of the anchor carrier CANNOT be exactly a multiple of <NUM>. Instead, an offset of the center frequency of the anchor carrier from the channel raster of <NUM> may be present. The offset is at most <NUM> according to the NB-IoT standard. Practically, the offset is <NUM> or <NUM>.

As an example, for the <NUM> LTE system bandwidth, there are two carriers in the guard band at each side of the in-band. The center frequencies are respectively <NUM> and <NUM> or -<NUM> and -<NUM> to LTE carrier center (e.g. assuming LTE carrier center is <NUM>). Based on the above-described center frequency of the anchor carrier meeting the <NUM> channel raster requirement in view of the maximum offset of <NUM>, only the carriers with the center frequencies of <NUM> and -<NUM> to LTE carrier center may be used as potential anchor carriers. The other two carriers with the center frequencies of <NUM> and -<NUM> may be used as potential non-anchor carriers. Incidentally, the carriers inside the in-band may also be used as potential non-anchor carriers.

Similarly, for the <NUM> LTE system bandwidth, only the carriers with center frequencies <NUM> and -<NUM> are eligible as potential anchor carriers. The other eight carriers in the guard band may be used as potential non-anchor carriers.

For <NUM> and <NUM> LTE system bandwidths, in order to meet the requirement of <NUM> channel raster requirement, <NUM> empty subcarriers (each has a bandwidth of <NUM>) should be added between the in-band PRB grid and the guard-band PRB grid. There is only one potential anchor carrier available for each side of the guard band. For the <NUM> LTE system bandwidth, the available potential anchor carriers have the center frequencies of <NUM> and -<NUM>. For the <NUM> LTE system bandwidth, the available potential anchor carriers have the center frequencies of <NUM> and -<NUM>. The other carriers in the guard band are potential non-anchor carriers.

<FIG> depicts one embodiment of non-anchor carrier frequency offset indication in the guard band operation mode, in which only the carriers in the guard band are potential non-anchor carriers, which means that the deployment of NBIOT is guardband (anchor carrier) + guardband (non-anchor carrier).

In the guard band operation mode, the LTE carrier bandwidth, the anchor carrier offset to LTE carrier, the non-anchor carrier offset and the frequency offset of the non-anchor carrier to the anchor carrier are to be indicated.

Two bits are used for the LTE carrier bandwidth, i.e. <NUM>, <NUM>, <NUM> and <NUM>. Table <NUM> shows the detailed implementation.

One bit is used to indicate the anchor carrier offset relative to the LTE carrier. Table <NUM> shows the detailed implementation.

For example, for the <NUM> LTE system bandwidth, the anchor carrier with the center frequency <NUM> is located in the higher/right guard band, while the anchor carrier with the center frequency -<NUM> is located in the lower/left guard band.

To be compatible with the in-band operation mode, two bits are used to indicate the non-anchor carrier offset. Table <NUM> shows the detailed implementation.

In Table <NUM>, "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> of the anchor carrier. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> of the anchor carrier. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> (in the condition that the cell ID is even) or subframe #<NUM> (in the condition that the cell ID is odd) of the non-anchor carrier. "<NUM>" means that the NB-SIB1 is transmitted in subframe #<NUM> (in the condition that the cell ID is even) or subframe #<NUM> (in the condition that the cell ID is odd) of the non-anchor carrier.

As shown in <FIG>, only the carrier close to the anchor carrier, i.e. those carriers labeled as A or B, is chosen as the non-anchor carrier. Therefore, in the condition that the non-anchor carrier being higher or lower than the anchor carrier is determined, the frequency offset of the non-anchor carrier to the anchor carrier is fixed. Therefore, the frequency offset of the non-anchor carrier to the anchor carrier depends on the bandwidth information of the LTE carrier.

Table <NUM> is the combination of Tables <NUM>-<NUM>.

For example, according to Table <NUM>, "<NUM><NUM><NUM>" represents that, in the <NUM> bandwidth, the non-anchor carrier is <NUM> higher than anchor carrier. In particular, "<NUM>" means that the LTE carrier bandwidth is <NUM> (see Table <NUM>). "<NUM>" means that the anchor carrier is higher than the LTE carrier (see Table <NUM>), which implies that the anchor carrier has a center frequency <NUM> (see <FIG>). "<NUM>" means that the non-anchor carrier is higher than the anchor carrier. By referring to <FIG>, there is only one choice of the non-anchor carrier with a center frequency <NUM>. Therefore, the offset of the non-anchor carrier to the anchor carrier is definitely <NUM> (<NUM> - <NUM>), assuming that the center of LTE carrier is <NUM>.

In the <NUM> and <NUM> system bandwidths, there is a three-subcarrier shift of the anchor carrier from the LTE carrier bandwidth to meet the requirement of <NUM> channel raster.

Another solution is also proposed in the guard band operation mode. in which the deployment of NBIOT is guardband (anchor carrier) + guardband (non-anchor carrier) or guardband (anchor carrier) + inband (non-anchor carrier). Tables <NUM> and <NUM> provide the implementation.

Table <NUM> is a combination of Tables <NUM> and <NUM>.

Table <NUM> provides the default offset of the non-anchor carrier to the anchor carrier. By referring to <FIG>, in the condition of <NUM> LTE system bandwidth, when the band with the center frequency <NUM> is the anchor carrier, the band with the center frequency -<NUM> (Y = <NUM>+<NUM> = <NUM>) will be configured as the non-anchor carrier. In the condition of <NUM> LTE system bandwidth, when the band with the center frequency <NUM> is the anchor carrier, the band with the center frequency <NUM> (X = <NUM> - <NUM> = <NUM>) or the band with the center frequency -<NUM> (Y = <NUM> + <NUM> = <NUM>) will be configured as the non-anchor carrier. X and Y can be similarly determined for the <NUM> and <NUM> LTE system bandwidths.

<FIG> depicts another embodiment of non-anchor carrier frequency offset indication in the guard band operation mode. In the embodiment of <FIG>, in the condition that the anchor carrier is located in the guard band, the non-anchor band is also located in the guard band. <FIG> shows that the non-anchor carrier may be located in the guard band or in the in-band.

In said another embodiment, the LTE carrier bandwidth, the anchor carrier offset to LTE carrier, the non-anchor carrier offset and the frequency offset of the non-anchor carrier to the anchor carrier are to be indicated.

One bit is used for the LTE carrier bandwidth, i.e. <NUM>/<NUM> and <NUM>/<NUM>. Table <NUM> shows the detailed implementation.

As shown in <FIG>, only the carrier adjacent to the anchor carrier, e.g. the carriers labeled as A or B, may be chosen as the non-anchor carrier. Therefore, in the condition that the relative offset (higher or lower) of the non-anchor carrier to the anchor carrier is determined, the offset of the non-anchor carrier to the anchor carrier is fixed.

For example, according to Table <NUM>, "<NUM><NUM><NUM>" represents that, in the <NUM>/<NUM> bandwidth, the non-anchor carrier is <NUM> higher than anchor carrier. The first "<NUM>" means <NUM>/<NUM> (see Table <NUM>). The second "<NUM>" means that the anchor carrier is higher than the LTE carrier (see Table <NUM>). The "<NUM>" means that the non-anchor carrier is higher than the anchor carrier (<NUM> - <NUM> = <NUM>).

Another solution is also proposed in the guard band operation mode. Tables <NUM> and <NUM> provide the implementation.

By referring to <FIG>, since there is a three-subcarrier shift of the anchor carrier from the LTE carrier in <NUM>/<NUM> bandwidths to meet the requirement of <NUM> channel raster, the band B as the non-anchor carrier has a <NUM> shift from the anchor carrier. On the other hand, for the LTE carrier <NUM>/<NUM> bandwidths, since there is no shift of the anchor carrier, both bands A and B have a <NUM> shift from the anchor carrier.

Table <NUM> is a summary of the embodiments.

As shown in Table <NUM>, in the in-band operation mode, a total of two bits are used for indication of the non-anchor carrier. In the standalone operation mode, up to seven bits may be used for indication of the non-anchor carrier, in which up to five spare bits may be used for indicating the frequency offset of the non-anchor carrier to the anchor carrier. In the guard band operation mode, a total of four or five bits are used for indication of the non-anchor carrier, in which up to three spare bits may be used for indicating the LTE bandwidth and the offset of the anchor carrier to the LTE carrier.

<FIG> is a schematic flow chart diagram illustrating an embodiment of a method <NUM> for indicating the frequency offset of the non-anchor carrier. In some embodiments, the method <NUM> is performed by an apparatus, such as the base unit <NUM>. In certain embodiments, the method <NUM> may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method <NUM> may include <NUM> transmitting a broadcast signal on an anchor carrier and transmitting a system information on a non-anchor carrier, wherein the broadcast signal includes a frequency offset of the non-anchor carrier to the anchor carrier.

In various embodiments, the frequency offset of the non-anchor carrier to the anchor carrier includes an information of the non-anchor carrier having a higher or lower frequency than the anchor carrier and an absolute frequency offset value of the non-anchor carrier to the anchor carrier or some combination thereof. In another embodiment, the frequency offset of the non-anchor carrier to the anchor carrier includes a relative frequency offset of the non-anchor carrier to the anchor carrier. The relative frequency offset of the non-anchor carrier to the anchor carrier may be symmetrical to zero. In some embodiment, the anchor carrier is in a guard band frequency of a LTE carrier, and the broadcast signal further includes bandwidth information of the LTE carrier. The broadcast signal may further include a frequency offset of the anchor carrier to the LTE carrier. The frequency offset of the non-anchor carrier to the anchor carrier may depend on the bandwidth information of the LTE carrier. In some embodiment, the non-anchor carrier is adjacent to the anchor carrier.

<FIG> is a schematic flow chart diagram illustrating a further embodiment of a method <NUM> for indicating the frequency offset of the non-anchor carrier. In some embodiments, the method <NUM> is performed by an apparatus, such as the remote unit <NUM>. In certain embodiments, the method <NUM> may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method <NUM> may include <NUM> receiving a broadcast signal on an anchor carrier and receiving system information on a non-anchor carrier, wherein the broadcast signal includes a frequency offset of the non-anchor carrier to the anchor carrier.

Claim 1:
A method performed by a base unit (<NUM>), the method comprising:
transmitting (<NUM>) a broadcast signal on an anchor carrier, wherein the anchor carrier is within a guard band associated with a Long-Term Evolution, LTE, carrier, and the broadcast signal is a narrowband master information block, NB-MIB, which includes bandwidth information of the LTE carrier selected from the group comprising <NUM>, <NUM>, <NUM>, and <NUM>; and
transmitting a narrowband system information, NB-SIB1, on a non-anchor carrier, wherein the non-anchor carrier is within the guard band associated with the LTE carrier,
wherein the broadcast signal indicates:
a frequency offset between the anchor carrier and the LTE carrier, and
a frequency offset between the non-anchor carrier and the anchor carrier, wherein the frequency offset between the non-anchor carrier and the anchor carrier indicates an absolute frequency offset value of the non-anchor carrier and the anchor carrier and whether the non-anchor carrier on which the system information is transmitted has a higher or lower frequency than the anchor carrier on which the NB-MIB is transmitted.