CN111165038A

CN111165038A - Method and apparatus for transmission of synchronization signal and system information

Info

Publication number: CN111165038A
Application number: CN201780095218.1A
Authority: CN
Inventors: 刘海静; 陈宇; 王河; 杨莉; S·赛瓦加纳帕西; R·拉塔萨克; M·希兰吉; N·曼加尔维德赫
Original assignee: Nokia Oyj; Alcatel Lucent SAS
Current assignee: Nokia Oyj; Alcatel Lucent SAS
Priority date: 2017-08-10
Filing date: 2017-08-10
Publication date: 2020-05-15
Anticipated expiration: 2037-08-10
Also published as: WO2019028719A1; CN111165038B

Abstract

Embodiments of the present disclosure relate to a method, a network device, and a terminal device for transmission of a narrowband synchronization signal and transmission of narrowband system information. In an example embodiment, a method implemented at a network device in a wireless communication system is provided. According to the method, a narrowband synchronization signal is transmitted to a terminal device on a first anchor carrier. It is determined whether to transmit the NB-MIB in the narrowband system information on the first anchor carrier or the second anchor carrier. The second anchor carrier has a first frequency offset relative to the first anchor carrier. Based on the determination, an NB-MIB is transmitted to the terminal device.

Description

Method and apparatus for transmission of synchronization signal and system information

Technical Field

Embodiments of the present disclosure generally relate to the field of communications, and in particular, to a method, a network device, and a terminal device for transmission of a narrowband synchronization signal and narrowband system information.

Background

Internet of things (IoT) technology is introduced into Public Land Mobile Network (PLMN) networks. For example, narrowband IoT (NB-IoT) is introduced for Long Term Evolution (LTE). Currently, NB-IoT supports only half-duplex Frequency Division Duplexing (FDD). Time Division Duplex (TDD) spectrum, however, exists worldwide, including regulatory environments and operator markets where the demand for NB-IoT is not met. Thus, there is a new Work Item (WI) enhanced on NB-IoT that aims to introduce TDD mode support to NB-IoT.

Disclosure of Invention

In general, example embodiments of the present disclosure provide methods, network devices, and terminal devices for transmission of narrowband synchronization signals and narrowband system information.

In a first aspect, a method implemented by a network device in a wireless communication system is provided. The method includes transmitting a narrowband synchronization signal to a terminal device on a first anchor carrier. The method also includes determining whether a narrowband master information block (NB-MIB) in narrowband system information is to be transmitted on the first anchor carrier or the second anchor carrier. The second anchor carrier has a first frequency offset relative to the first anchor carrier. The method also includes transmitting the NB-MIB to the terminal device based on the determination.

In some embodiments, the method further comprises determining a pattern of the narrowband synchronization signal based on the determination.

In some embodiments, determining the pattern of the narrowband synchronization signal includes determining a pattern of a Narrowband Primary Synchronization Signal (NPSS).

In some embodiments, transmitting the narrowband synchronization signal comprises: transmitting a Narrowband Primary Synchronization Signal (NPSS) in a first subframe on a first anchor carrier; and transmitting a Narrowband Secondary Synchronization Signal (NSSS) in a second subframe on the first anchor carrier, a subframe offset between the first subframe and the second subframe being determined based on the determination.

In some embodiments, the method further comprises: in response to determining to transmit the NB-MIB on the first anchor carrier, determining to transmit a first narrowband system information block (NB-SIB) in the narrowband system information on the first anchor carrier or a second anchor carrier, the first NB-SIB including information that enables the terminal device to camp in a cell provided by the network device, and transmitting the first NB-SIB based on the determining to transmit the first NB-SIB on the first anchor carrier or the second anchor carrier. In some embodiments, the method further comprises: in response to determining to transmit the NB-MIB on the second anchor carrier, the first NB-SIB is transmitted on the second anchor carrier.

In some embodiments, the NB-MIB comprises at least one of: an indication of a subframe in which to transmit the first NB-SIB; and an indication of one of the first and second anchor carriers on which to transmit the first NB-SIB.

In some embodiments, the method further includes transmitting a second NB-SIB in the narrowband system information on at least one of the first anchor carrier, the second anchor carrier, and a third anchor carrier, the second NB-SIB being different from the first NB-SIB, the third anchor carrier having a second frequency offset relative to the first anchor carrier.

In some embodiments, the first NB-SIB includes information related to at least one of: a subframe in which the second NB-SIB is transmitted; and at least one of the first, second, and third anchor carriers on which to transmit the second NB-SIB.

In some embodiments, transmitting the NSSS comprises transmitting the NSSS, the NSSS comprising an identifier of a cell provided by the network device.

In some embodiments, the frequency of the second anchor carrier is associated with an identifier of the cell.

In a second aspect, a method implemented at a terminal device in a wireless communication system is provided. The method includes receiving a narrowband synchronization signal from a network device on a first anchor carrier. The method also includes determining whether a narrowband master information block (NB-MIB) in narrowband system information is to be received on a first anchor carrier or a second anchor carrier, the second anchor carrier having a first frequency offset relative to the first anchor carrier. The method also includes receiving an NB-MIB from the network device based on the determination.

In some embodiments, the determining comprises determining based on a pattern of the received narrowband synchronization signal.

In some embodiments, receiving the narrowband synchronization signal comprises: receiving a Narrowband Primary Synchronization Signal (NPSS); and the determining comprises determining based on the received pattern of the NPSS.

In some embodiments, receiving the narrowband synchronization signal comprises: receiving a Narrowband Primary Synchronization Signal (NPSS) in a first subframe on a first anchor carrier; and receiving a Narrowband Secondary Synchronization Signal (NSSS) on the first anchor carrier in a second subframe, the second subframe having a determined subframe offset relative to the first subframe.

In some embodiments, the determining comprises determining based on the subframe offset.

In some embodiments, the method further comprises: in response to determining to receive the NB-MIB on the first anchor carrier, determining to receive a first narrowband system information block (NB-SIB) in the narrowband system information on the first anchor carrier or a second anchor carrier, the first NB-SIB including information that enables the terminal device to camp in a cell provided by the network device, and receiving the first NB-SIB based on the determining to receive the first NB-SIB on the first anchor carrier or the second anchor carrier; and in response to determining to receive the NB-MIB on the second anchor carrier, receive the first NB-SIB on the second anchor carrier.

In some embodiments, the NB-MIB comprises at least one of: an indication of a subframe in which to receive the first NB-SIB; and an indication of one of the first and second anchor carriers on which to receive the first NB-SIB.

In some embodiments, the method further comprises: receiving a second NB-SIB in the narrowband system information on at least one of the first, second, and third anchor carriers, the second NB-SIB being different from the first NB-SIB, the third anchor carrier having a second frequency offset relative to the first anchor carrier.

In some embodiments, wherein the first NB-SIB includes information related to at least one of: a subframe in which a second NB-SIB is to be received; and at least one of the first, second, and third anchor carriers on which to receive the second NB-SIB.

In some embodiments, receiving the NSSS comprises: an NSSS is received that includes an identifier of a cell provided by a network device.

In some embodiments, the method further includes determining a frequency of a second anchor carrier based on an identifier of the cell.

In a third aspect, a network device in a wireless communication system is provided. The network device includes a processor; and a memory coupled to the processing unit and storing instructions that, when executed by the processing unit, cause the network device to perform the method according to the first aspect.

In a fourth aspect, a terminal device in a wireless communication system is provided. The terminal device includes a processor; and a memory coupled to the processing unit and storing instructions that, when executed by the processing unit, cause the terminal device to perform the method according to the second aspect.

In a fifth aspect, a computer program product tangibly stored on a computer-readable storage medium is provided. The computer program product comprises instructions which, when executed on at least one processor, cause the at least one processor to perform the method according to the first aspect or the second aspect.

In a sixth aspect, a computer-readable storage medium having instructions stored thereon is provided. The instructions, when executed on at least one processor, cause the at least one processor to perform a method according to the first aspect or the second aspect.

Other features of the present disclosure will become readily apparent from the following description.

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent from the following more detailed description of some embodiments of the present disclosure in which:

FIG. 1 is a block diagram of a communication environment in which embodiments of the present disclosure may be implemented;

fig. 2 is a flow diagram illustrating a process for transmission of NB synchronization signals and NB system information, in accordance with some embodiments of the present disclosure;

fig. 3 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB in accordance with one embodiment of the present disclosure;

fig. 4 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB in accordance with another embodiment of the present disclosure;

fig. 5 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB in accordance with yet another embodiment of the present disclosure;

fig. 6 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB in accordance with yet another embodiment of the present disclosure;

fig. 7 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, NB-MIB, and NB-SIB1, according to one embodiment of the present disclosure;

fig. 8 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, NB-MIB, and NB-SIB1, according to another embodiment of the present disclosure;

fig. 9 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, NB-MIB, and NB-SIB1, according to yet another embodiment of the present disclosure;

figure 10 is a diagram illustrating anchor carrier configurations for other SIBs according to an embodiment of the present disclosure;

FIG. 11 illustrates a flow diagram of an example method according to some embodiments of the present disclosure;

fig. 12 shows a flowchart of an example method according to some other embodiments of the present disclosure; and

FIG. 13 is a simplified block diagram of a device suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numbers refer to the same or similar elements.

Detailed Description

The principles of the present disclosure will now be described with reference to a few exemplary embodiments. It is understood that these examples are described for illustrative purposes only and to aid those skilled in the art in understanding and enabling the present disclosure, and do not set forth any limitations on the scope of the present disclosure. The disclosure described herein may be implemented in a variety of other ways besides those described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

As used herein, the term "network device" or "base station" (BS) refers to a device that is capable of providing or hosting a cell or coverage area in which a terminal device may communicate. Examples of network devices include, but are not limited to, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a Remote Radio Unit (RRU), a Radio Head (RH), a Remote Radio Head (RRH), a low power node (such as a femto node, pico node, etc.). For purposes of discussion, some embodiments will be described below with reference to an eNB as an example of a network device.

As used herein, the term "terminal device" refers to any device having wireless or wired communication capabilities. Examples of terminal devices include, but are not limited to, User Equipment (UE), personal computers, desktop computers, mobile phones, cellular phones, smart phones, Personal Digital Assistants (PDAs), portable computers, image capture devices such as digital cameras, gaming devices, music storage and playback devices, or internet devices that enable wireless or wired internet access and browsing, among other functions. In some examples, the end devices include internet of things (IoT) devices, which are networks of physical objects or "things" embedded with electronics, software, sensors, and connectivity to enable the objects to exchange data with manufacturers, carriers, and/or other connected devices. For purposes of discussion, some embodiments will be described below with reference to a UE as an example of a terminal device, and the terms "terminal device" and "user equipment" (UE) may be used interchangeably within the context of the present disclosure.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term "comprising" and its variants should be understood as open-ended terms, meaning "including but not limited to". The term "based on" should be understood as "based at least in part on". The terms "one embodiment" and "one embodiment" should be understood as "at least one embodiment". The term "another embodiment" should be understood as "at least one other embodiment". The terms "first," "second," and the like may refer to different or the same object. Other definitions (explicit and implicit) may be included below.

In some examples, a value, process, or device is referred to as "best," "lowest," "highest," "minimum," "maximum," or the like. It should be understood that such description is intended to indicate that a selection may be made among many functional alternatives that may be used, and that such selection need not be better, smaller, higher, or otherwise preferred than other selections.

Fig. 1 illustrates an example communication network 100 in which embodiments of the present disclosure may be implemented. Network 100 includes network device 110 and terminal device 120 served by network device 110. The service area of network device 110 is referred to as a cell 102. It should be understood that the number of network devices and terminal devices is for illustration purposes only and is not limiting in any way. Network 100 may include any suitable number of network devices and terminal devices suitable for implementing embodiments of the present disclosure. Although not shown, it should be understood that one or more terminal devices may be located in cell 102 and served by network device 110.

Communications in network 100 may conform to any suitable standard, including but not limited to global system for mobile communications (GSM), extended coverage global system for mobile internet of things (EC-GSM-IoT), Long Term Evolution (LTE), LTE evolution, LTE advanced (LTE-a), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), GSM EDGE Radio Access Network (GERAN), and so forth. Further, the communication may be performed according to any generational communication protocol currently known or to be developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, and fifth generation (5G) communication protocols.

In communication network 100, network device 110 may communicate data and control information to terminal device 120, and terminal device 120 may also communicate data and control information to network device 110. The link from network device 110 to terminal device 120 is referred to as the downlink, and the link from terminal device 120 to network device 110 is referred to as the uplink.

In general, two different duplex modes may be used for transmissions between terminal device 120 and network device 110: frequency Division Duplex (FDD) and Time Division Duplex (TDD). In the TDD mode, a single bandwidth is shared between UL and DL, wherein the sharing is performed by allocating different periods to the UL and DL.

In TDD mode, there are seven different UL-DL switching modes, referred to as UL-DL configurations #0 to #6, which are schematically shown in table 1.

Table 1: UL-DL configuration

As can be seen from table 1, the DL time resources become less in TDD mode due to Time Division Multiplexing (TDM) of UL and DL on a single anchor carrier compared to FDD mode. For example, in UL-DL configuration #0, only about 35% of the time resources are available for DL transmission. Thus, as TDD mode support is introduced to NB-IoT, ensuring DL transmission with fewer DL time resources in TDD mode presents some challenges.

As is known, before the terminal device 120 can communicate with the network device 110, the terminal device 120 must perform a cell search to find a cell provided by the network device 110 and to acquire synchronization with the cell. To assist terminal device 120 in cell search, network device 110 transmits a narrowband synchronization signal to terminal device 120 on an anchor carrier.

By means of the cell search, the terminal device 120 can achieve synchronization with the cell. In order to access the cell, the terminal device 120 needs to acquire narrowband system information of the cell. Examples of narrowband system information may include, but are not limited to, a narrowband master information block (NB-MIB) and a narrowband system information block (NB-SIB).

For LTE in TDD mode, synchronization signals and system information can only be sent on a single anchor carrier. The transmission of the synchronization signal and MIB on the anchor carrier will occupy (1+1/2+ 1)/10-25% of the DL time resources, and the transmission of SIBs on the anchor carrier will occupy approximately 25% of the DL time resources. For NB-IoT in TDD mode, a large amount of narrowband synchronization signals and narrowband system information need to be transmitted in order to provide extended coverage. In some UL-DL configurations with fewer DL time resources, this overhead may exceed the load capacity of a single anchor carrier.

To address at least some of the above issues and other potential issues, in accordance with an embodiment of the present disclosure, a solution for transmission of narrowband synchronization signals and narrowband system information is presented. In this solution, a network device may use multiple anchor carriers to transmit narrowband synchronization signals and narrowband system information. Thus, transmission can be ensured with sufficient DL time resources over multiple carriers.

The principles and implementations of the present disclosure will be described in detail below with reference to fig. 2, where fig. 2 illustrates a process 200 for transmission of narrowband synchronization signals and narrowband system information in accordance with an embodiment of the present disclosure. For purposes of discussion, the process 200 will be described with reference to fig. 1. Process 200 may involve network device 110 and terminal device 120 in fig. 1.

Network device 110 transmits (210) a narrowband synchronization signal to terminal device 120 on a first anchor carrier. Examples of narrowband synchronization signals may include, but are not limited to, Narrowband Primary Synchronization Signals (NPSS) and Narrowband Secondary Synchronization Signals (NSSS). Accordingly, terminal device 120 receives a narrowband synchronization signal from network device 110 on the first anchor carrier.

Network device 110 determines (220) whether to send the NB-MIB in the narrowband system information on the first anchor carrier or the second anchor carrier. The second anchor carrier has a first frequency offset relative to the first anchor carrier. The frequency of the first anchor carrier may be determined based on the radio access technology employed in network 100. For example, for NB-IoT, the frequency of the first anchor carrier may be 180 kHz. Of course, any suitable frequency for the first anchor carrier may be employed. The scope of the present disclosure is not limited in this respect.

In some embodiments, network device 110 may determine whether to transmit the NB-MIB on the first anchor carrier or the second anchor carrier based on the available DL time resources.

In an example embodiment, network device 110 may determine the time resources of the available DL according to the UL-DL configuration to be used. As can be seen from table 1, some UL-DL configurations such as UL-DL configuration #2, #3, #4, and #5 have more DL time resources (i.e., more than six DL subframes) in one frame, while other UL-DL configurations such as UL-DL configuration #0 and UL-DL configuration #6 have less DL time resources (i.e., two or three DL subframes) in one frame.

In this regard, for a UL-DL configuration with more DL time resources, network device 110 may determine to transmit NB-MIB on the first anchor carrier. That is, both the narrowband synchronization signal and the NB-MIB are transmitted on the first anchor carrier. For a UL-DL configuration with less DL time resources, network device 110 may determine to transmit NB-MIB on the second anchor carrier. In this manner, DL time resources on both the first anchor carrier and the second anchor carrier may be used for transmission of narrowband synchronization signals and narrowband system information.

In an example embodiment, network device 110 may determine available DL time resources according to a traffic model employed by network device 110. For example, network device 110 may provide multimedia broadcast/multicast service (MBMS) to terminal device 120. To this end, the network device 110 will send an MBMS message to the terminal device 120 that occupies a large amount of DL time resources. Although UL-DL configurations such as UL-DL configurations #2, #3, #4, and #5 have more DL time resources in one frame, the DL time resources may be insufficient to transmit narrowband synchronization signals and narrowband system information. In this case, network device 110 may determine to transmit NB-MIB on the second anchor carrier.

In other embodiments, network device 110 may determine whether to send the NB-MIB on the first anchor carrier or the second anchor carrier based on a pre-configuration. For example, the second anchor carrier may be pre-configured for NB-MIB transmission on both the network device 110 and the terminal device 120 sides. Due to the pre-configuration, terminal device 120 need not identify the anchor carrier on which the NB-MIB is transmitted. Therefore, an increase in decoding complexity is not caused at the terminal device 120. This is very important for low cost terminal equipment.

Still referring to fig. 2, in correspondence with the determination (220) at network device 110, terminal device 120 determines (230) whether to receive the NB-MIB on the first anchor carrier or the second anchor carrier.

Network device 110 transmits (240) the NB-MIB to terminal device 120 based on the determination (220). Accordingly, terminal device 120 receives the NB-MIB from network device 110 based on the determination (230). In turn, terminal device 120 may initiate access to a cell provided by network device 110 by using the received narrowband synchronization signal and narrowband system information.

It should be understood that while the actions shown in fig. 2 are depicted in a particular order, this should not be understood as requiring that such actions be performed in the particular order shown or in sequential order to achieve desirable results. In some cases, the actions may be performed in a different order than shown in FIG. 2. For example, act 220 may be performed prior to act 210. Furthermore, parallel execution of more actions may be advantageous. For example, acts 210 and 240 may be performed in parallel.

To assist in understanding the solutions proposed in the present disclosure, details of embodiments of the present disclosure will be described below with reference to fig. 3 to 9. In fig. 3 to 9, the frames are numbered 0, 1, … …, N (where N is a natural number), and each frame includes ten subframes numbered 0 to 9. The frames numbered 0, 1, … …, N are also referred to as frame #0, frame #1, … …, frame # N. Subframes numbered 0 to 9 are also referred to as subframe #0, subframe #1, … …, subframe # 9.

Fig. 3 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB in accordance with one embodiment of the present disclosure. As shown, NPSS301, NSSS302, and NB-MIB303 are transmitted on a first anchor carrier. NPSS301 is transmitted in subframe #0 of each frame, NSSS302 is transmitted in subframe #5 of each even frame (e.g., frame #0, frame #2, … …), and NB-MIB is transmitted in subframe #9 of each frame.

Fig. 4 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB according to another embodiment of the present disclosure. As shown, NPSS301 is transmitted in subframe #0 of each frame on the first anchor carrier, NSSS302 is transmitted in subframe #5 of each even frame on the first anchor carrier, and NB-MIB303 is transmitted in subframe #0 of each frame on the second anchor carrier.

In embodiments where the second anchor carrier is not pre-configured for transmission of NB-MIB303 on both network device 110 and terminal device 120 sides, terminal device 120 should be able to identify the anchor carrier on which NB-MIB303 is transmitted to correctly receive NB-MIB303 from network device 110. To this end, in some embodiments, network device 110 may determine a pattern of the narrowband synchronization signal based on the determination (220). In this way, terminal device 120 can identify the anchor carrier on which NB-MIB303 is transmitted based on the pattern.

In embodiments where NPSS301 is to be transmitted, network device 110 may indicate the anchor carrier on which to transmit NB-MIB303 by using the mode of NPSS 301.

For example, NPSS301 may be given by the following equation:

wherein d is_lThe term (n) denotes NPSS301, u denotes a ZC root sequence index, and s (l) denotes a predetermined sequence.

To indicate the anchor carrier on which NB-MIB303 is transmitted, network device 110 may employ a different ZC root sequence index or a different predetermined sequence s (l) to determine a different NPSS mode. For example, network device 110 may employ a ZC root sequence index of value 5 or s (l) ═ 1,1,1,1, -1, -1,1,1, -1,1] to determine the first mode of NPSS301 to indicate that NB-MIB303 is transmitted on the first anchor carrier. Network device 110 may also employ a ZC root sequence index of value 6 or s (l) ═ 1,1,1, -1, -1, -1,1, -1, -1 to determine the second mode of NPSS301 to indicate that NB-MIB303 is transmitted on the second anchor carrier. Upon receiving NPSS301 having the first mode, terminal device 120 may determine that NB-MIB303 is transmitted on the first anchor carrier. Upon receiving NPSS301 having the second mode, terminal device 120 may determine that NB-MIB303 is transmitted on the second anchor carrier.

In embodiments where NPSS301 and NSSS302 are to be transmitted, network device 110 may indicate the anchor carrier on which to transmit NB-MIB303 by using the relative subframe locations of NPSS301 and NSSS 302.

Specifically, NPSS301 is to be transmitted in a first subframe on a first anchor carrier, and NSSS302 is to be transmitted in a second subframe on the first anchor carrier. Network device 110 may determine a subframe offset between the first subframe and the second subframe based on the determining (220).

For example, network device 110 may determine the subframe offset to be 1 based on determining to transmit NB-MIB303 on the first anchor carrier. Network device 110 may then transmit NPSS301 in a first subframe and NSSS302 in a second subframe having a subframe offset of 1 relative to the first subframe, as shown in fig. 5.

Fig. 5 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB according to yet another embodiment of the present disclosure. As shown, NPSS301, NSSS302, and NB-MIB303 are all transmitted on a first anchor carrier. NPSS301 is transmitted in subframe #0 of each frame, NSSS302 is transmitted in subframe #9 of each even frame (e.g., frame #1, frame #3, … …), and NB-MIB303 is transmitted in subframe #5 of each frame. As can be seen from fig. 5, there is a subframe offset of "1" between subframe #0 for transmitting NPSS301 and subframe #9 for transmitting NSSS 302. Upon receiving NPSS301 and NSSS302, terminal device 120 may determine that NB-MIB303 is transmitted on the first anchor carrier based on subframe offset "1".

For another example, network device 110 may determine the subframe offset to be 5 based on determining to transmit NB-MIB303 on the second anchor carrier. Network device 110 may then transmit NPSS301 in a first subframe and NSSS302 in a second subframe at a subframe offset of 5 relative to the first subframe, as shown in fig. 6.

Fig. 6 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, and NB-MIB according to yet another embodiment of the present disclosure. As shown, NPSS301 is transmitted in subframe #0 of each frame on the first anchor carrier, NSSS302 is transmitted in subframe #5 of each even frame on the first anchor carrier, and NB-MIB303 is transmitted in subframe #0 of each frame on the second anchor carrier. As can be seen from fig. 6, there is a subframe offset of 5 between subframe #0 for transmitting NPSS301 and subframe #5 for transmitting NSSS 302. Upon receiving NPSS301 and NSSS302, terminal device 120 may determine that NB-MIB303 is transmitted on the second anchor carrier based on the subframe offset of 5.

After determining to receive NB-MIB303 on the second anchor carrier, terminal device 120 needs to determine the frequency of the second anchor carrier.

In some embodiments, the frequency of the second anchor carrier may be preconfigured on both sides of network device 110 and terminal device 120.

In other embodiments, the frequency of the second anchor carrier may be associated with an identifier of a cell provided by network device 110. Network device 110 may transmit an NSSS that includes an identifier of a cell. Upon receiving the NSSS, the terminal device 120 may obtain an identifier of the cell from the NSSS. In turn, terminal device 120 may determine the frequency of the second anchor carrier based on the identifier of the cell.

As described above, examples of the narrowband system information may include NB-MIB and NB-SIB. Typically, the NB-MIB includes a limited amount of narrowband system information, and the NB-SIB includes a major portion of the narrowband system information.

In particular, NB-SIBs are characterized by the type of information they contain. In particular, the NB-SIBs may include a first NB-SIB, also referred to as NB-SIB 1. The first NB-SIB or NB-SIB1 includes information enabling terminal device 120 to camp in a cell provided by network device 110. In addition to NB-SIB1, NB-SIBs may also include one or more other NB-SIBs, such as NB-SIB2, NB-SIB3, NB-SIB4, NB-SIB5, NB-SIB14, NB-SIB15, NB-SIB16, NB-SIB20, and NB-SIB 22. For example, NB-SIB2 includes information that terminal device 120 needs in order to be able to access a cell.

The transmission of NPSS, NSSS, and MIB is described above with reference to fig. 3 to 6. Hereinafter, transmission of NB-SIBs will be described with reference to fig. 7 to 10.

In some embodiments, the following may be preconfigured: the NB-SIB1 and NB-MIB are transmitted on the same anchor carrier (e.g., a first anchor carrier or a second anchor carrier). In such embodiments, the NB-MIB may include an indication of the subframe in which the NB-SIB1 is transmitted. For example, the indication of the subframe may occupy three bits in the NB-MIB.

Fig. 7 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, NB-MIB, and NB-SIB1, according to one embodiment of the present disclosure. As shown in fig. 7, NPSS301, NSSS302, NB-MIB303, and NB-SIB1304 are all sent on the first anchor carrier. Upon receiving NPSS301 and NSSS302, terminal device 120 may determine that NB-MIB303 is also transmitted on the first anchor carrier. Then, according to the pre-configuration, terminal device 120 may determine that NB-SIB1304 is transmitted on the same anchor carrier as NB-MIB 303. After reading NB-MIB303, terminal device 120 may determine the subframe in which NB-SIB1304 is transmitted, e.g., subframe #6 in fig. 7.

Fig. 8 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, NB-MIB, and NB-SIB1, according to another embodiment of the present disclosure. As shown in fig. 8, NPSS301 and NSSS302 are transmitted on a first anchor carrier, and NB-MIB303 and NB-SIB1304 are transmitted on a second anchor carrier. Upon receiving NPSS301 and NSSS302, terminal device 120 may determine that NB-MIB303 is transmitted on the second anchor carrier. Then, according to the pre-configuration, terminal device 120 may determine that NB-SIB1304 is transmitted on the same anchor carrier as NB-MIB 303. After reading NB-MIB303, terminal device 120 may determine the subframe in which NB-SIB1304 is transmitted, e.g., subframe #5 in fig. 8.

In other embodiments, the NB-MIB and NB-SIB1 may be sent on different anchor carriers. For example, the NB-MIB may be transmitted on a first anchor carrier, and the NB-SIB1 may be transmitted on a second anchor carrier. Information related to the second anchor carrier to be used for transmission of the NB-SIB1 may be explicitly or implicitly given by the NB-MIB.

In one example, information related to the location of the second anchor carrier frequency may be associated with an identifier of a cell of network 100. Accordingly, terminal device 120 may determine information related to the second anchor carrier frequency location based on the identifier of the cell of network 100.

In another example, one or more fixed frequency offsets between the first anchor carrier and the second anchor carrier may be preconfigured. Each fixed frequency offset may be associated with an indication or index. In addition, the NB-MIB may include an index of one of the fixed frequency offsets.

Fig. 9 is a diagram illustrating anchor carrier configurations for NPSS, NSSS, NB-MIB, and NB-SIB1, according to yet another embodiment of the present disclosure. As shown in fig. 9, NPSS301, NSSS302, and NB-MIB303 are transmitted on a first anchor carrier, and NB-SIB1304 is transmitted on a second anchor carrier. NSSS302 is transmitted in subframe #9 of each even frame. NB-MIB303 is transmitted on subframe #5 of each frame. The NB-MIB303 may include an index of one of the fixed frequency offsets and an indication of the subframe in which the NB-SIB1304 is transmitted.

Upon receiving NPSS301 and NSSS302, terminal device 120 may determine that NB-MIB303 is transmitted on the same carrier as NPSS301 and NSSS302, i.e., that NB-MIB303 is also transmitted on the first anchor carrier. By reading NB-MIB303, terminal device 120 acquires frequency information of an anchor carrier on which NB-SIB1304 is transmitted. Further, terminal device 120 may acquire information related to a subframe (e.g., subframe #0 in fig. 9) in which NB-SIB1304 is transmitted.

Figure 10 is a diagram illustrating anchor carrier configurations for other SIBs according to an embodiment of the present disclosure. As shown in fig. 10, NPSS301 is transmitted in subframe #0 on the first anchor carrier. NSSS302 is transmitted in subframe #5 of each even frame on the first anchor carrier. NB-MIB303 is transmitted in subframe #0 on the second anchor carrier. Other SIBs 305 are transmitted on at least one of the first, second, and third anchor carriers. The third anchor carrier has a second frequency offset relative to the first anchor carrier. Further, the following may be configured in advance: the NB-SIB1304 is transmitted on the same carrier as the NB-MIB 303.

Upon receiving NPSS301 and NSSS302, terminal device 120 may determine that NB-MIB303 is transmitted on the second anchor carrier. After reading NB-MIB303 in subframe #0 on the second anchor carrier, terminal device 120 may determine that subframe #5 is used for transmission of NB-SIB1304 on the second anchor carrier. Terminal device 120 then receives NB-SIB1304 in subframe #5 on the second anchor carrier. The NB-SIB1304 can include information related to at least one of: a subframe on which the other SIB is transmitted, and at least one of the first anchor carrier, the second anchor carrier, and the third anchor carrier on which the other SIB is transmitted. Thus, terminal device 120 may receive other SIBs in the indicated subframes on the corresponding anchor carrier.

An example of a portion of NB-SIB1 is as follows:

in this example, a number (i.e., -55 … 54) is used to show the PRB index offset relative to the first anchor carrier.

Fig. 11 illustrates a flow diagram of an example method 1100 implemented at a network device in a wireless communication system in accordance with some embodiments of the present disclosure. Method 1100 may be implemented at network device 110 as shown in fig. 1. For discussion purposes, the method 1100 will be described with reference to fig. 1 from the perspective of the network device 110.

At block 1110, network device 110 transmits a narrowband synchronization signal to terminal device 120 on a first anchor carrier.

At block 1120, network device 110 determines whether to send a narrowband master information block (NB-MIB) in narrowband system information on a first anchor carrier or a second anchor carrier, the second anchor carrier having a first frequency offset relative to the first anchor carrier.

At block 1130, network device 110 sends the NB-MIB to terminal device 120 based on the determination.

In some embodiments, method 1100 further includes determining a pattern of the narrowband synchronization signal based on the determination.

In some embodiments, determining the pattern of the narrowband synchronization signal comprises determining a pattern of NPSS.

In some embodiments, transmitting the narrowband synchronization signal comprises: transmitting the NPSS in a first subframe on a first anchor carrier; and transmitting the NSSS in the second subframe on the first anchor carrier. A subframe offset between the first subframe and the second subframe is determined based on the determination.

In some embodiments, the method 1100 further comprises: in response to determining to transmit the NB-MIB on the first anchor carrier, determining to transmit a first narrowband system information block (NB-SIB) in the narrowband system information on the first anchor carrier or a second anchor carrier, the first NB-SIB including information that enables the terminal device to camp in a cell provided by the network device, and transmitting the first NB-SIB based on the determining to transmit the first NB-SIB on the first anchor carrier or the second anchor carrier. The method 1100 further comprises: in response to determining to transmit the NB-MIB on the second anchor carrier, the first NB-SIB is transmitted on the second anchor carrier.

In some embodiments, the NB-MIB comprises at least one of: an indication of a subframe in which to transmit the first NB-SIB; and an indication of one of the first and second anchor carriers on which the first NB-SIB is transmitted.

In some embodiments, the method 1100 further includes transmitting a second NB-SIB in the narrowband system information on at least one of the first anchor carrier, the second anchor carrier, and a third anchor carrier, the second NB-SIB being different from the first NB-SIB, the third anchor carrier having a second frequency offset relative to the first anchor carrier.

In some embodiments, the first NB-SIB includes information related to at least one of: a subframe in which the second NB-SIB is transmitted, and at least one anchor carrier of the first, second, and third anchor carriers on which the second NB-SIB is transmitted.

It should be understood that all operations and features related to network device 110 described above with reference to fig. 2 through 10 are equally applicable to method 1100 and have similar effects. Details will be omitted for the sake of simplicity.

Fig. 12 illustrates a flow diagram of an example method 1200 implemented at a terminal device in a wireless communication system in accordance with some embodiments of the present disclosure. Method 1200 may be implemented at terminal device 120 as shown in fig. 1. For discussion purposes, the method 1200 will be described with reference to fig. 1 from the perspective of the terminal device 120.

At block 1210, the terminal device 120 receives a narrowband synchronization signal from the network device 110 on a first anchor carrier.

At block 1220, terminal device 120 determines whether to receive the NB-MIB in the narrowband system information on a first anchor carrier or a second anchor carrier, the second anchor carrier having a first frequency offset relative to the first anchor carrier.

At block 1230, terminal device 120 receives the NB-MIB from network device 110 based on the determination.

In some embodiments, receiving the narrowband synchronization signal comprises: receiving the NPSS; and the determining comprises determining based on the received pattern of the NPSS.

In some embodiments, receiving the narrowband synchronization signal comprises: receiving an NPSS in a first subframe on a first anchor carrier; and receiving the NSSS in a second subframe on the first anchor carrier, the second subframe having a determined subframe offset relative to the first subframe.

In some embodiments, the method 1200 further comprises: in response to determining to receive the NB-MIB on the first anchor carrier, determining to receive a first NB-SIB in the narrowband system information on the first anchor carrier or a second anchor carrier, the first NB-SIB including information that enables the terminal device to camp in a cell provided by the network device, and receiving the first NB-SIB based on the determining to receive the first NB-SIB on the first anchor carrier or the second anchor carrier; and in response to determining to receive the NB-MIB on the second anchor carrier, receive the first NB-SIB on the second anchor carrier.

In some embodiments, the method 1200 further includes receiving a second NB-SIB in the narrowband system information on at least one of the first anchor carrier, the second anchor carrier, and the third anchor carrier. The second NB-SIB is different from the first NB-SIB, and the third anchor carrier has a second frequency offset relative to the first anchor carrier.

In some embodiments, the first NB-SIB includes information related to at least one of: a subframe in which a second NB-SIB is to be received; and at least one of the first, second, and third anchor carriers on which to receive the second NB-SIB.

In some embodiments, receiving the NSSS comprises receiving the NSSS, the NSSS comprising an identifier of a cell provided by the network device.

In some embodiments, method 1200 further includes determining a frequency of a second anchor carrier based on an identifier of the cell.

It should be understood that all operations and features related to the terminal device 120 described above with reference to fig. 2 through 10 are equally applicable to the method 1200 and have similar effects. Details will be omitted for the sake of simplicity.

Fig. 13 is a simplified block diagram of an apparatus 1300 suitable for implementing embodiments of the present disclosure. Device 1300 may be considered another example implementation of terminal device 120 or network device 110 as shown in fig. 1 and 2. Accordingly, device 1300 may be implemented at terminal device 120 or network device 110, or as at least a portion of terminal device 120 or network device 110.

As shown, device 1300 includes a processor 1310, a memory 1320 coupled to processor 1310, a suitable Transmitter (TX) and Receiver (RX)1340 coupled to processor 1310, and a communication interface coupled to TX/RX 1340. Memory 1320 stores at least a portion of program 1330. TX/RX 1340 is used for bi-directional communication. TX/RX 1340 has at least one antenna to facilitate communication, although in practice an access node referred to in this application may have several antennas. The communication interface may represent any interface required for communication with other network elements, such as an X2 interface for bidirectional communication between enbs, an S1 interface for communication between a Mobility Management Entity (MME)/serving gateway (S-GW) and an eNB, a Un interface for communication between an eNB and a Relay Node (RN), or a Uu interface for communication between an eNB and a terminal device.

Programs 1330 are assumed to include program instructions that, when executed by associated processor 1310, enable device 1300 to operate in accordance with embodiments of the present disclosure, as described herein with reference to fig. 2-12. The embodiments herein may be implemented by computer software executable by the processor 1310 of the device 1300, or by hardware, or by a combination of software and hardware. The processor 1310 may be configured to implement various embodiments of the present disclosure. Further, the combination of the processor 1310 and the memory 1320 may form a processing device 1350 suitable for implementing various embodiments of the present disclosure.

The memory 1320 may be of any type suitable to the local technology network and may be implemented using any suitable data storage technology, such as non-transitory computer readable storage media, semiconductor-based storage devices, magnetic storage devices and systems, optical storage devices and systems, fixed memory and removable memory, as non-limiting examples. Although only one memory 1320 is shown in device 1300, there may be several physically different memory modules within device 1300. The processor 1310 may be of any type suitable to the local technology network, and may include one or more of general purpose computers, special purpose computers, microprocessors, Digital Signal Processors (DSPs) and processors based on a multi-core processor architecture, as non-limiting examples. The device 1300 may have multiple processors, such as application specific integrated circuit chips that are time dependent from a clock synchronized to the main processor.

In general, the various embodiments of the disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of the embodiments of the disclosure are illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as included in program modules, that are executed in a device on a target real or virtual processor to perform the processes or methods described above with reference to any of figures 2, 6 and 7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within local or distributed devices. In a distributed facility, program modules may be located in both local and remote memory storage media.

Program code for performing the methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the execution of the program codes by the processor or controller causes the functions/operations specified in the flowchart and/or block diagram to be performed. The program code may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine-readable medium, which 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. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Also, while the above discussion contains several specific implementation details, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Although the disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method implemented at a network device in a wireless communication system, comprising:

sending a narrowband synchronization signal to the terminal equipment on the first anchor carrier;

determining whether a narrowband master information block (NB-MIB) in narrowband system information is to be transmitted on the first anchor carrier or a second anchor carrier, the second anchor carrier having a first frequency offset relative to the first anchor carrier; and

transmitting the NB-MIB to the terminal device based on the determination.

2. The method of claim 1, further comprising:

determining a pattern of the narrowband synchronization signal based on the determination.

3. The method of claim 2, wherein determining the pattern of the narrowband synchronization signal comprises:

a pattern of a Narrowband Primary Synchronization Signal (NPSS) is determined.

4. The method of claim 1, wherein transmitting the narrowband synchronization signal comprises:

transmitting a Narrowband Primary Synchronization Signal (NPSS) in a first subframe on the first anchor carrier; and

transmitting a Narrowband Secondary Synchronization Signal (NSSS) in a second subframe on the first anchor carrier, a subframe offset between the first subframe and the second subframe being determined based on the determining.

5. The method of any of claims 1 to 4, further comprising:

in response to determining that the NB-MIB is to be transmitted on the first anchor carrier,

determining whether a first narrowband system information block (NB-SIB) in narrowband system information is to be transmitted on the first anchor carrier or the second anchor carrier, the first NB-SIB comprising information enabling the terminal device to camp in a cell provided by the network device, and

transmitting the first NB-SIB based on determining whether the first NB-SIB will be transmitted on the first anchor carrier or the second anchor carrier; and

transmitting the first NB-SIB on the second anchor carrier in response to determining that the NB-MIB is to be transmitted on the second anchor carrier.

6. The method of claim 5, wherein the NB-MIB comprises at least one of:

an indication of a subframe in which the first NB-SIB is transmitted; and

an indication of one of the first and second anchor carriers on which the first NB-SIB is transmitted.

7. The method of claim 6, further comprising:

transmitting a second NB-SIB in the narrowband system information on at least one of the first, second, and third anchor carriers, the second NB-SIB being different from the first NB-SIB, the third anchor carrier having a second frequency offset from the first anchor carrier.

8. The method of claim 7, wherein the first NB-SIB includes information related to at least one of:

a subframe in which the second NB-SIB is transmitted, an

The at least one of the first, second, and third anchor carriers on which the second NB-SIB is transmitted.

9. The method of claim 1, wherein transmitting the narrowband synchronization signal comprises:

transmitting a Narrowband Secondary Synchronization Signal (NSSS), the NSSS including an identifier of a cell provided by the network device.

10. The method of claim 9, wherein a frequency of the second anchor carrier is associated with the identifier of the cell.

11. A method implemented at a terminal device in a wireless communication system, comprising:

receiving a narrowband synchronization signal from a network device on a first anchor carrier;

determining whether a narrowband master information block (NB-MIB) in narrowband system information is to be received on the first anchor carrier or a second anchor carrier having a first frequency offset relative to the first anchor carrier; and

receiving the NB-MIB from the network device based on the determination.

12. The method of claim 11, wherein the determining comprises:

based on a pattern of the received narrowband synchronization signal.

13. The method of claim 12, wherein:

receiving the narrowband synchronization signal comprises:

receiving a Narrowband Primary Synchronization Signal (NPSS); and

the determining includes:

based on a received pattern of the NPSS.

14. The method of claim 11, wherein receiving the narrowband synchronization signal comprises:

receiving a Narrowband Primary Synchronization Signal (NPSS) in a first subframe on the first anchor carrier; and

receiving a Narrowband Secondary Synchronization Signal (NSSS) in a second subframe on the first anchor carrier, the second subframe having a predetermined subframe offset relative to the first subframe.

15. The method of claim 14, wherein the determining comprises:

based on the subframe offset.

16. The method of any of claims 11 to 15, further comprising:

in response to determining that the NB-MIB is to be received on the first anchor carrier,

determining whether a first narrowband system information block (NB-SIB) in narrowband system information is to be received on the first anchor carrier or the second anchor carrier, the first NB-SIB comprising information enabling the terminal device to camp in a cell provided by the network device, and

receiving the first NB-SIB based on determining whether the first NB-SIB is to be received on the first anchor carrier or the second anchor carrier; and

receiving the first NB-SIB on the second anchor carrier in response to determining that the NB-MIB is to be received on the second anchor carrier.

17. The method of claim 16, wherein the NB-MIB comprises at least one of:

an indication of a subframe in which the first NB-SIB is to be received, an

An indication of one of the first and second anchor carriers on which the first NB-SIB is to be received.

18. The method of claim 17, further comprising:

receiving a second NB-SIB in the narrowband system information on at least one of the first, second, and third anchor carriers, the second NB-SIB being different from the first NB-SIB, the third anchor carrier having a second frequency offset from the first anchor carrier.

19. The method of claim 18, wherein the first NB-SIB includes information related to at least one of:

a subframe in which the second NB-SIB is to be received, an

The at least one of the first, second, and third anchor carriers over which the second NB-SIB is to be received.

20. The method of claim 11, wherein receiving the narrowband synchronization signal comprises:

receiving a Narrowband Secondary Synchronization Signal (NSSS), the NSSS including an identifier of a cell provided by the network device.

21. The method of claim 20, further comprising:

determining a frequency of the second anchor carrier based on the identifier of the cell.

22. A network device, comprising:

a processor; and

a memory coupled to the processor and having stored thereon instructions that, when executed by the processor, cause the network device to perform the method of any of claims 1-10.

23. A terminal device, comprising:

a processor; and

a memory coupled to the processor and having stored thereon instructions that, when executed by the processor, cause the terminal device to perform the method of any of claims 11-21.

24. A computer-readable medium having instructions stored thereon, which, when executed by at least one processing unit of a machine, cause the machine to perform the method of any one of claims 1 to 10.

25. A computer-readable medium having instructions stored thereon, which, when executed by at least one processing unit of a machine, cause the machine to perform the method of any of claims 11 to 21.