WO2020029218A1

WO2020029218A1 - Neighbor cell measurement and reporting

Info

Publication number: WO2020029218A1
Application number: PCT/CN2018/099810
Authority: WO
Inventors: Srinivasan Selvaganapathy; Jussi-Pekka Koskinen; Haitao Li; Rapeepat Ratasuk
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2018-08-10
Filing date: 2018-08-10
Publication date: 2020-02-13
Also published as: CN112771909A

Abstract

Embodiments of the present disclosure relate to devices, methods, apparatuses and computer readable storage media for neighbor cell measurement and reporting. In example embodiments, a method implemented at a terminal device is provided. The method comprises receiving, from a network device, a configuration to perform neighbor cell measurement during an idle mode. The network device provides at least a serving cell and a first neighbor cell. The method further comprises determining, based on the configuration, whether the neighbor cell measurement is to be performed by the terminal device. The method further comprises, in response to determining that the neighbor cell measurement is to be performed by the terminal device, measuring signal quality of the first neighbor cell during the idle mode. In addition, the method further comprises transmitting a result of the neighbor cell measurement to the network device. The result includes a cell identity and the measured signal quality of the first neighbor cell. In this way, the functionality of Self-Organized Network (SON) can be supported in Narrow Band Internet of Things (NB-IoT) without increasing energy consumption and complexity of IoT devices.

Description

NEIGHBOR CELL MEASUREMENT AND REPORTING

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of communications, and in particular, to methods, devices and computer readable storage media for neighbor cell measurement and reporting.

BACKGROUND

Automated configuration of neighbor cell lists, the so-called Automatic Neighbor Relation (ANR) function, is one of Self-Organized Network (SON) functions deployed in a communication network. Traditionally, for example in Long Term Evolution (LTE) , a terminal device (for example, a user equipment (UE) ) in the connected mode measures neighbor cells and reports Physical Cell Identities (PCIs) of the neighbor cells to a network device (for example, an evolved NodeB (eNB) ) . Then, the terminal device determines and reports a Cell Global Identity (CGI) for a selected neighbor cell (for example, the neighbor cell with a selected PCI) . The network device may create, based on these reports, a neighbor relationship table for each of the neighbor cells.

Once the neighbor relationship table is created, the network device may refer to the PCIs for any connected mode mobility. In case that there is a failure reported for a PCI and the failure indicates a PCI confusion problem, the network device may mark the PCI for CGI reporting. For example, if another terminal device enters into the connected mode and reports the PCI, the network device may instruct the other terminal device to report the CGI for this PCI. In order to determine and report the CGI, the other terminal device may need to synchronize to the target neighbor cell, read specific system information of the neighbor cell and return back to the serving cell in the connected mode. This mechanism will take additional time and require terminal devices to switch between different cells.

SUMMARY

In general, example embodiments of the present disclosure provide methods, devices and computer readable storage media for neighbor cell measurement and reporting.

In a first aspect, a terminal device is provided which comprises at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the terminal device to receive, from a network device, a configuration to perform neighbor cell measurement during an idle mode. The network device provides at least a serving cell and a first neighbor cell. The terminal device is further caused to determine, based on the configuration, whether the neighbor cell measurement is to be performed by the terminal device. The terminal device is further caused to, in response to determining that the neighbor cell measurement is to be performed by the terminal device, measure signal quality of the first neighbor cell during the idle mode. The terminal device is further caused to transmit a result of the neighbor cell measurement to the network device. The result includes a cell identity and the measured signal quality of the first neighbor cell.

In a second aspect, a network device is provided which comprises at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the network device to transmit, to a terminal device, a configuration to perform neighbor cell measurement during an idle mode. The network device provides at least a serving cell and a first neighbor cell. The network device is further caused to receive a result of the neighbor cell measurement from the terminal device. The result includes at least a cell identity and signal quality of the first neighbor cell.

In a third aspect, there is provided a method implemented at a terminal device. The method comprises receiving, from a network device, a configuration to perform neighbor cell measurement during an idle mode. The network device provides at least a serving cell and a first neighbor cell. The method further comprises determining, based on the configuration, whether the neighbor cell measurement is to be performed by the terminal device. The method further comprises, in response to determining that the neighbor cell measurement is to be performed by the terminal device, measuring signal quality of the first neighbor cell during the idle mode. In addition, the method further comprises transmitting a result of the neighbor cell measurement to the network device. The result includes a cell identity and the measured signal quality of the first neighbor cell.

In a fourth aspect, there is provided a method implemented at a network device. The method comprises transmitting, to a terminal device, a configuration to perform neighbor cell measurement during an idle mode. The network device provides at least a serving cell and a first neighbor cell. The method further comprises receiving a result of the neighbor cell measurement from the terminal device. The result includes at least a cell identity and signal quality of the first neighbor cell.

In a fifth aspect, there is provided an apparatus comprising means to perform the steps of the method according to the third or fourth aspect.

In a sixth aspect, there is provided a computer readable storage medium that stores a computer program thereon. The computer program, when executed by a processor of a device, causes the device to perform the method according to the third or fourth aspect.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

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

FIG. 2 shows a schematic diagram of an example process for neighbor cell measurement according to some embodiments of the present disclosure;

FIG. 3 shows a schematic diagram of an example process for CGI reporting according to some embodiments of the present disclosure;

FIG. 4 shows a flowchart of an example method for neighbor cell measurement according to some embodiments of the present disclosure;

FIG. 5 shows a flowchart of an example method for CGI reporting according to some embodiments of the present disclosure;

FIG. 6 shows a flowchart of an example method for neighbor cell measurement according to some embodiments of the present disclosure;

FIG. 7 shows a flowchart of an example method for CGI reporting according to some embodiments of the present disclosure; and

FIG. 8 is a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones 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 skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. 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. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) :

(i) a combination of analog and/or digital hardware circuit (s) with software/firmware and

(ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

As used herein, the term “wireless communication network” refers to a network following any suitable wireless communication standards, such as New Radio (NR) , Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , and so on. The “wireless communication network” may also be referred to as a “wireless communication system. ” Furthermore, communications between network devices, between a network device and a terminal device, or between terminal devices in the wireless communication network may be performed according to any suitable communication protocol, including, but not limited to, Global System for Mobile Communications (GSM) , Universal Mobile Telecommunications System (UMTS) , Long Term Evolution (LTE) , New Radio (NR) , wireless local area network (WLAN) standards, such as the IEEE 802.11 standards, and/or any other appropriate wireless communication standard either currently known or to be developed in the future.

As used herein, the term “network device” refers to any suitable device at a network side of a communication network. The network device may include any suitable device in an access network of the communication network, for example, including a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a New Radio (NR) NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, a low power node such as a femto, a pico, and so forth, depending on the applied terminology and technology.

The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE) , a Subscriber Station (SS) , a Portable Subscriber Station, a Mobile Station (MS) , or an Access Terminal (AT) . The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA) , portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , USB dongles, smart devices, wireless customer-premises equipment (CPE) and the like. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

As yet another example, in an Internet of Things (IOT) scenario, a terminal device may represent a machine or other device that performs monitoring and/or measurement, and transmits the results of such monitoring and/or measurements to another terminal device and/or network device. The terminal device may in this case be a machine-to-machine (M2M) device, which may in a 3GPP context be referred to as a machine-type communication (MTC) device. As one particular example, the terminal device may be a UE implementing the 3GPP Narrow Band Internet of Things (NB-IoT) standard. Examples of such machines or devices are sensors, metering devices such as power meters, industrial machinery, or home or personal appliances, for example refrigerators, televisions, personal wearables such as watches etc. In other scenarios, a terminal device may represent a vehicle or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation.

As described above, in LTE, the ANR function works based on the UE in the connected mode measuring and reporting PCIs of neighbor cells followed by the UE reporting the CGI for a selected PCI. This mechanism will take additional time and require the UE to switch between different cells.

In a NB-IoT network, not all of the SON functions are required as the network characteristics are different from the LTE network. For example, the connected mode mobility is not supported in the NB-IoT network, and thus any SON function for improving the performance of the connected mode mobility may not be required. Only some of the SON functions are required for improving the performance in an idle mode. For example, the neighbor relationship table containing the right set of PCIs may be needed, since it enables the terminal device to have optimum performance in cell reselection. Without such table, the terminal device has to blindly detect all of possible PCIs during the cell reselection, which will increase power consumption and latency. With additional information on the neighbors known in advance, the terminal device can make a right decision to move to a suitable cell during the cell reselection. The mechanism for avoiding PCI confusion may also be required during the idle mode mobility. Without such mechanism for avoiding PCI confusion, the session transfer may fail during the idle mode mobility.

If the ANR function is required for the NB-IoT network, the neighbor cell measurement and CGI reporting are needed. However, the neighbor cell measurement and CGI reporting by the terminal device in connected mode in LTE may be not suitable for the NB-IoT network. This is because measuring neighbor cells in the connected mode will increase device complexity and power consumption of an IoT device. Therefore, for the ANR function in the NB-IoT network, the neighbor cell measurement is required to be performed by the terminal device in an idle mode. However, triggering the neighbor cell measurements from all of the terminal devices in the idle mode may not be optimum, since this may result in redundant measurements as well as a huge load on the network device.

According to embodiments of the present disclosure, there is proposed a solution for neighbor cell measurement and CGI reporting. In this solution, a terminal device can be selected for neighbor cell measurement and reporting in an idle mode, so as to reduce the impact of additional measurements from all of the terminal devices in the idle mode. The result of the neighbor cell measurement can be aligned to Discontinuous Reception (DRX) occasions, so as to distribute the uplink transmissions from a plurality of terminal devices. Dynamic control of the neighbor cell measurement and reporting through paging occasions can be enabled, so as to avoid redundant measurements by a plurality of terminal devices and avoid unnecessary transmissions from the plurality of terminal devices for sending similar measurement results. For CGI reporting, the network device can redirect the terminal device to idle mode to measure CGI for a selected PCI along with additional information, so as to enable CGI reporting in an energy efficient manner. Moreover, since the network device knows that the terminal device is expected to come back for CGI reporting, pre-allocation of a random access preamble and the payload size for such reporting can be enabled, so as to further improve the efficiency of the transmission of the CGI report.

FIG. 1 shows an example communication network 100 in which implementations of the present disclosure can be implemented. The communication network 100 includes a network device 120 and terminal devices 110-1, 110-2 ... and 110-N, which can be collectively referred to as “terminal device (s) ” 110. The network 100 can provide one or more cells 102 to serve the terminal device 110. It is to be understood that the number of network devices, terminal devices and/or cells is given for the purpose of illustration without suggesting any limitations to the present disclosure. The communication network 100 may include any suitable number of network devices, terminal devices and/or cells adapted for implementing implementations of the present disclosure.

Communications in the communication system 100 may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) and the fifth generation (5G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Divided Multiple Address (CDMA) , Frequency Divided Multiple Address (FDMA) , Time Divided Multiple Address (TDMA) , Frequency Divided Duplexer (FDD) , Time Divided Duplexer (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Divided Multiple Access (OFDMA) and/or any other technologies currently known or to be developed in the future.

FIG. 2 shows a schematic process of an example process 200 for neighbor cell measurement according to some embodiments of the present disclosure. The process 200 may involve the network device 120 and the terminal device 110 served by the network device 120.

As shown in FIG. 2, the network device 120 transmits 210, to the terminal device 110, a configuration to perform neighbor cell measurement during an idle mode. The network device 120 may provide a serving cell and one or more neighbor cells to serve the terminal device 110. In response to receiving the configuration from the network device 120, the terminal device 110 determines 220, based on the configuration, whether the neighbor cell measurement is to be performed by the terminal device 110.

In some embodiments, the configuration may include a RSRP threshold to trigger the neighbor cell measurement for ANR purpose. For example, the RSRP threshold may be broadcasted by the network device 120 via a system information block (SIB) . In this case, the terminal device 110 may measure RSRP of the serving cell. If the measured RSRP of the serving cell is below the RSRP threshold, the terminal device 110 may determine that the neighbor cell measurement is to be performed by itself. That is, if the RSRP based neighbor cell measurement is configured to the terminal device 110, the terminal device 110 may attempt to check against the RSRP threshold whenever it measures the serving cell as part of Radio Resource Management (RRM) measurements.

Alternatively, or in addition, the network device 120 may also configure the periodicity for the neighbor cell measurement to the terminal device 110. In this case, the terminal device 110 may check at least once the RSRP of the serving cell against the RSRP threshold for the neighbor cell measurement within a period.

Alternatively, in some embodiments, the configuration may include a criterion to be satisfied by an identity (ID) of a terminal device that will perform the neighbor cell measurement. In this case, the terminal device 110 may check if its ID satisfies the criterion (for example, if the ID of the terminal device 110 modulo 9 is equal to 1 or if the terminal device 110 belongs to a certain subscription service) . In response to the ID of the terminal device 110 satisfying the criterion, the terminal device 110 may determine that the neighbor cell measurement is to be performed by itself. For example, the terminal device 110 may perform the neighbor cell measurement within a measurement occasion without checking the RSRP threshold.

Alternatively, or in addition, in some embodiments, the configuration may include control information on the neighbor cell measurement (also referred to as idle-mode-measurement-control-information (IMCI) in the following) . For example, the configuration including the IMCI can be transmitted dynamically from the network device 120 to the terminal device 110 on a paging occasion, so as to implement dynamic control of the neighbor cell measurement and reporting. In this case, whether the terminal device 110 needs to perform the neighbor cell measurement during a measurement occasion can be determined based on the IMCI received on an earlier paging occasion.

In some embodiments, the IMCI may be transmitted from the network device 120 to the terminal device 110 via a Radio Resource Control (RRC) message on a paging occasion. Alternatively, in some embodiments, the IMCI may be transmitted from the network device 120 to the terminal device 110 via Downlink Control Information (DCI) on a paging occasion. Alternatively, in some embodiments, some or all of the IMCI can be transmitted as additional information in a RRC paging message scheduled on a paging occasion.

In some embodiments, the IMCI transmitted from the network device 120 to the terminal device 110 may indicate at least one of the following: whether the neighbor cell measurement is to be performed by the terminal device 110; whether a result of the neighbor cell measurement is to be transmitted to the network device 120; timing information on the neighbor cell measurement (for example, time interval or periodicity information on the neighbor cell measurement ) ; a modification to the RSRP threshold for triggering the neighbor cell measurement; and so on.

In some embodiments, in response to the IMCI received from the network device 120 indicating that the neighbor cell measurement is to be performed, the terminal device 110 may determine that the neighbor cell measurement is to be performed by the terminal device 110. For example, the IMCI may indicate whether the terminal device 110 should check against the RSRP threshold during the next RRM measurement occasion. If the IMCI indicates that the terminal device 110 should check against the RSRP threshold during the next RRM measurement occasion, the terminal device 110 will measure the RSRP of the serving cell against the RSRP threshold for the neighbor cell measurement. In response to the RSRP of the serving cell being below the RSRP threshold for the neighbor cell measurement, the neighbor cell measurement will be triggered. For example, the IMCI may also indicate a modification to the RSRP threshold to the terminal device 110, which enables the terminal device 110 to change the RSRP threshold dynamically without changing the system information. In this event, the terminal device 110 may update the RSRP threshold base on the IMCI received from the network device 120, and use the updated RSRP threshold for determining whether the neighbor cell measurement is to be performed.

As shown in Fig. 2, in response to determining that the neighbor cell measurement is to be performed by the terminal device 110, the terminal device 110 measures 230 respective signal quality of the one or more neighbor cells during the idle mode. In some embodiments, the signal quality measured for the one or more neighbor cells may include at least one of the following: Reference Signal Received Power (RSRP) , Reference Signal Received Quality (RSRQ) or Relative Signal Strength Indication (RSSI) . For the purpose of discussion, in the following, some embodiments will be described with reference to RSRP as an example of the signal quality. However, it is to be understood that this is merely for the purpose of illustration, without suggesting any limitations to the present disclosure.

In some embodiments, as described above, if a RSRP threshold for triggering the neighbor cell measurement is configured to the terminal device 110, the terminal device 110 may attempt to check against the RSRP threshold whenever it measures the RSRP of the serving cell. Once the terminal device 110 determines that the measured RSRP of the serving cell is below the RSRP threshold, it may measure respective signal quality of the one or more neighbor cells during the idle mode.

In some embodiments, the periodicity for the neighbor cell measurement may be configured to the terminal device 110. The terminal device 110 may check at least once the RSRP of the serving cell against the RSRP threshold for the neighbor cell measurement within a period. Once the terminal device 110 determines that the measured RSRP of the serving cell is below the RSRP threshold, it may measure respective signal quality of the one or more neighbor cells during the idle mode.

In some embodiments, as described above, if the terminal device 110 is selected for the neighbor cell measurement based on its identity, it may measure respective signal quality of the one or more neighbor cells within a measurement occasion without checking the RSRP threshold.

In some embodiments, as described above, the IMCI transmitted dynamically from the network device 120 to the terminal device 110 may indicate timing information on the neighbor cell measurement (for example, time interval or periodicity information on the neighbor cell measurement) . In this case, for example, the terminal device 110 may measure respective signal quality of the one or more neighbor cells based on the timing information indicated by the IMCI received from the network device 120.

Alternatively, or in addition, in some embodiments, the result of the neighbor cell measurement can be stored at the terminal device 110 prior to being transmitted to the network device 120.

As shown in FIG. 2, the process 200 proceeds to 240, where the terminal device 110 transmits 240 a result of the neighbor cell measurement to the network device 120.

In some embodiments, the result may include a cell identity and the measured signal quality of a neighbor cell (also referred to a “first neighbor cell” ) which is included in the one or more neighbor cells. Additionally, in some embodiment, the first neighbor cell may be associated with the best signal quality among the one or more neighbor cells. Alternatively, in some embodiments, the result may include respective cell identities and signal quality of some or all of the one or more neighbor cells according to the configuration. In some embodiments, the cell identity included in the result may include at least one of a Physical Cell Identity (PCI) and a Cell Global identity (CGI) . For the purpose of discussion, in the following, some embodiments will be described with reference to the PCI as an example of the cell identity. However, it is to be understood that this is merely for the purpose of illustration, without suggesting any limitations to the present disclosure.

In some embodiments, the network device 120 may configure a timer to the terminal device 110 to wait for an uplink transmission occasion where the result of the neighbor cell measurement is to be transmitted. For example, if the timer expires, the terminal device 110 may attempt to transmit the result of the neighbor cell measurement on the uplink transmission occasion. For example, the network device 120 may configure the timer to the terminal device 110 for aligning the transmission of the result to paging occasions within a DRX cycle.

Alternatively, or in addition, in some embodiments, the terminal device 110 may have been configured with relaxed RRM measurement. In this case, for example, the terminal device 110 may not report the result of the neighbor cell measurement unless the signal quality change of a neighbor cell exceeds a predetermined threshold. Alternatively, or in addition, in some embodiments, if the neighbor cell with the best signal quality is not included in the whitelist broadcasted via a SIB, the result of the neighbor cell measurement may be transmitted via an early data transmission.

In some embodiments, for example, the result of the neighbor cell measurement may be transmitted to the network device 120 via a RRC message. For example, the result may be transmitted to the network device 120 via a RRC message in Message 3 (MSG3) of a random access procedure (also referred to as a “first RRC message” herein) . Examples of the first RRC message may include but not limited to a RRC connection request message, a RRC connection re-establishment request message, or a RRC connection resume request message. As another example, the result may be transmitted to the network device 120 via a RRC message in Message 5 (MSG5) of a random access procedure (also referred to as a “second RRC message” herein) . Examples of the second RRC message may include but not limited to a RRC connection setup complete message, a RRC connection re-establishment complete message or a RRC connection resume complete message. As yet another example, the result may be transmitted to the network device 120 via a RRC message subsequent to MSG5 of a random access procedure (also referred to as a “third RRC message” herein) . That is, the terminal device 110 may transmit the result of the neighbor cell measurement after the random access procedure completes.

Alternatively, or in addition, in some embodiments, the transmission of the result of the neighbor cell measurement can be triggered by the IMCI. In some embodiments, for example, if there is no uplink transmission scheduled and the result of the measurement has been stored at the terminal device 110, the terminal device 110 may wait for the IMCI to trigger the transmission of the result. As described above, the IMCI received dynamically on a paging occasion may indicate whether the result of the neighbor cell measurement is to be transmitted in this occasion or not. In response to the IMCI indicating that the result of the neighbor cell measurement is to be transmitted, the terminal device 110 may transmit the result of the neighbor cell measurement as part of the paging occasion.

It can be seen that, the dynamic control of the neighbor cell measurement and reporting (such as, via the IMCI) can avoid redundant measurements by a plurality of terminal devices and avoid unnecessary transmissions from the plurality of terminal devices for sending similar measurement results. For example, the network device 120 can analyze measurement results from some terminal devices and then decide whether the neighbor cell measurement and reporting from other terminal devices is needed. On the other hand, if the number of measurement results is not sufficient, more neighbor cell measurement and reporting can be enabled by changing the RSRP threshold dynamically without modifying the system information.

The neighbor cell measurement and reporting during the idle mode have been discussed as above. This mechanism enables network control over a large number of terminal devices for the neighbor cell measurement and PCI reporting during the idle mode, so as to support the SON functionality in NB-IoT without increasing energy consumption and complexity of the terminal devices.

In some scenarios, for example, when the network device 120 receives PCIs measured and reported by one or more terminal devices 110, the network device 120 may further indicate whether CGI reporting is needed for one or more of the PCIs. Alternatively, in other scenarios, if the network device 120 does not know the CGI for a neighbor cell, the network device 120 may indicate, to a terminal device 110, that CGI reporting is needed for the neighbor cell.

FIG. 3 shows a schematic process of an example process 300 for CGI reporting according to some embodiments of the present disclosure. The process 300 may involve the network device 120 and the terminal device 110 served by the network device 120. For example, the process 300 may be performed subsequent to or in parallel with the process 200.

As shown in FIG. 3, the network device 120 transmits 310 a message requesting a Cell Global identity (CGI) of a second neighbor cell to the terminal device 110. For example, the message includes a PCI of the second neighbor cell.

In some embodiments, the second neighbor cell may be a neighbor cell indicated in the result of the neighbor cell measurement reported by the terminal device 110 at 240 of the process 200. For example, the second neighbor cell may be the same as the first neighbor cell indicated in the result of the neighbor cell measurement. If the network device 120 receives the result of the neighbor cell measurement including the PCI of the first neighbor cell from the terminal device 110 and wants to know the CGI of the first neighbor cell, the network device 120 may transmit the message including the PCI of the first neighbor cell to the terminal device 110. Alternatively, in other embodiments, the second neighbor cell of which the CGI is requested may not come from the result reported by the terminal device 110 at 240 of the process 200. For example, if the terminal device 110 sends a RRC connection re-establishment message including a PCI of the second neighbor cell for which the network device 120 does not know the CGI, the network device 120 may send a new RRC message requesting the terminal device 110 to report the CGI of the second neighbor cell.

In some embodiments, the message requesting the CGI of the second neighbor cell, which is transmitted from the network device 120 to the terminal device 110, may be one of the following: a RRC connection release message, and a RRC message in Message 4 (MSG4) of a random access procedure (also referred to as a “fourth RRC message” herein) . For example, assume that the second neighbor cell is a neighbor cell indicated in the result of the neighbor cell measurement reported by the terminal device 110 at 240 of the process 200. If the PCI of the second neighbor cell (for example, included in the result of the neighbor cell measurement) is transmitted from the terminal device 110 to the network device 120 via a RRC message in MSG3 of a random access procedure, the message requesting the CGI of the second neighbor cell transmitted from the network device 120 to the terminal device 110 may be a RRC connection release message. Alternatively, in some embodiments, if the PCI of the second neighbor cell (for example, included in the result of the neighbor cell measurement) is transmitted from the terminal device 110 to the network device 120 via a RRC message in MSG3 of a random access procedure, the message requesting the CGI of the second neighbor cell transmitted from the network device 120 to the terminal device 110 may be the fourth RRC message in MSG4 of the random access procedure.

Additionally, in some embodiments, the message requesting the CGI of the second neighbor cell transmitted from the network device 120 may include a dedicated random access preamble for transmission of the CGI report.

As shown in FIG. 3, in response to receiving, from the network device 120, the message requesting the CGI of the second neighbor cell, the terminal device 110 may obtain 320 the CGI information from the second neighbor cell.

In some embodiments, in order to obtain the information on the CGI of the second neighbor cell, the terminal device 110 may enter the idle mode to synchronize to the second neighbor cell and measure the CGI of the second neighbor cell during the idle mode. The terminal device 110 may then return back to the serving cell to report the CGI information.

The terminal device 110 may transmit 330 the dedicated random access preamble to the network device 120. Upon detecting this dedicated random access preamble, the network device 120 allocates a resource for transmission of the information on the CGI of the second neighbor cell. For example, the network device 120 may determine a transport block size (TBS) to be allocated for transmission of the information on the CGI of the second neighbor cell. Since a small size is needed for reporting the PCI-CGI mapping, for example, the TBS of 32 bits can be allocated for transmission of the information on the CGI of the second neighbor cell. Then, the network device 120 may indicate 340 the allocated resource to the terminal device 110.

In some embodiments, the network device 120 may setup a timer to determine the timing advance needed for the CGI reporting. For ex. ample, if the terminal device 110 can complete the CGI measurement and return to the serving cell before the timer expires, the timing advance needed for the CGI reporting may be 0. In this case, the dedicated random access preamble can be considered as a scheduling request for the CGI reporting. The network device 120 may transmit DCI indicating the allocated resource for the CGI reporting directly. Otherwise, if the terminal device 110 completes the CGI measurement and returns to the serving cell after the timer expires, the timing advance needed for the CGI reporting may be greater than 0. In this case, the network device 120 may transmit a random access response indicating information on the timing advance and uplink resource allocation to the terminal device 110.

As shown in FIG. 3, the process 300 proceeds to 350, where the terminal device 110 transmits 350 the information on the CGI of the second neighbor cell to the network device 120 based on the allocated resource.

In some embodiments, in response to receiving the DCI indicating the uplink grant for transmission of the information on the CGI of the second neighbor cell, the terminal device 110 may transmit the information on the CGI of the second neighbor cell based on the uplink grant. Alternatively, in some embodiments, in response to receiving a random access response indicating the uplink resource allocation and the information on the timing advance, the terminal device 110 may transmit the information on the CGI of the second neighbor cell based on the allocated resource and the timing advance information.

The above mechanism enables CGI reporting in an energy efficient manner. This is because whenever CGI reporting is required for a selected PCI, the terminal device will be redirected to the idle mode to measure the CGI for the PCI. Moreover, since the network device knows that the terminal device is expected to come back for CGI reporting, pre-allocation of the payload size for such reporting can be enabled, so as to further improve the efficiency of the transmission of the CGI report.

FIG. 4 shows a flowchart of an example method 400 for neighbor cell measurement according to some embodiments of the present disclosure. The method 400 can be implemented at the terminal device 110 as shown in FIG. 1. It is to be understood that the method 400 may include additional blocks not shown and/or may omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

At block 410, a terminal device receives, from a network device, a configuration to perform neighbor cell measurement during an idle mode, the network device providing at least a serving cell and a first neighbor cell.

At block 420, the terminal device determines, based on the configuration, whether the neighbor cell measurement is to be performed by the terminal device;

In some embodiments, the configuration includes a RSRP threshold to trigger the neighbor cell measurement. In some embodiments, the terminal device determines whether the neighbor cell measurement is to be performed by the terminal device by: measuring RSRP of the serving cell; and in response to the measured RSRP of the serving cell being below the RSRP threshold, determining that the neighbor cell measurement is to be performed by the terminal device.

In some embodiments, the configuration includes a criterion to be satisfied by respective identities of a group of terminal devices for performing the neighbor cell measurement. In some embodiments, the terminal device determines whether the neighbor cell measurement is to be performed by the terminal device by: in response to an identity of the terminal device satisfying the criterion, determining that the neighbor cell measurement is to be performed by the terminal device.

In some embodiments, the configuration includes control information on the neighbor cell measurement. The control information on the neighbor cell measurement indicates at least one of the following: whether the neighbor cell measurement is to be performed; whether the result of the neighbor cell measurement is to be transmitted; timing information on the neighbor cell measurement; and a modification to a RSRP threshold for triggering the neighbor cell measurement.

In some embodiments, the configuration including the control information on the neighbor cell measurement is received from the network device via any of the following: a Radio Resource Control (RRC) message transmitted on a paging occasion; and Downlink Control Information (DCI) transmitted on a paging occasion.

In some embodiments, the terminal device determines whether the neighbor cell measurement is to be performed by the terminal device by: in response to the control information on the neighbor cell measurement indicating that the neighbor cell measurement is to be performed, determining that the neighbor cell measurement is to be performed by the terminal device.

At block 430, in response to determining that the neighbor cell measurement is to be performed by the terminal device, the terminal device measures signal quality of the first neighbor cell during the idle mode.

In some embodiments, the terminal device measures the signal quality of the first neighbor cell by: in response to the control information indicating the timing information on the neighbor cell measurement, measuring the signal quality of the first neighbor cell based on the timing information.

In some embodiments, the signal quality measured for the first neighbor cell includes at least one of the following: Reference Signal Received Power (RSRP) , Reference Signal Received Quality (RSRQ) and Relative Signal Strength Indication (RSSI) .

At block 440, the terminal device transmits a result of the neighbor cell measurement to the network device, the result including a cell identity and the measured signal quality of the first neighbor cell.

In some embodiments, the terminal device transmits the result of the neighbor cell measurement by: in response to the control information on the neighbor cell measurement indicating that the result of the neighbor cell measurement is to be transmitted, transmitting the result of the neighbor cell measurement to the network device.

In some embodiments, the cell identity includes at least one of the following: a PCI; and a CGI.

In some embodiments, the cell identity is a PCI, and the terminal device 110 transmits the result of the neighbor cell measurement via a RRC message.

In some embodiments, the RRC message includes one of the following: a first RRC message in MSG3 of a random access procedure; a second RRC message in MSG5 of the random access procedure; and a third RRC message subsequent to MSG5 of the random access procedure.

FIG. 5 shows a flowchart of an example method 500 for CGI reporting according to some embodiments of the present disclosure. The method 500 can be implemented at the terminal device 110 as shown in FIG. 1. For example, the method 500 can be implemented subsequent to or in parallel with the method 400. It is to be understood that the method 500 may include additional blocks not shown and/or may omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

At block 510, in response to receiving, from a network device, a message requesting a Cell Global identity (CGI) of a second neighbor cell provided by the network device, a terminal device obtains information on the CGI of the second neighbor cell, the message including a PCI of the second neighbor cell.

In some embodiments, the terminal device obtains the information on the CGI of the second neighbor cell by: entering the idle mode to synchronize to the second neighbor cell; obtaining the information on the CGI of the second neighbor cell during the idle mode; and returning back to the serving cell.

In some embodiments, the message received from the network device includes one of the following: a RRC connection release message; and a fourth RRC message in MSG4 of a random access procedure.

At block 520, the terminal device transmits the information on the CGI of the second neighbor cell to the network device.

In some embodiments, the message received from the network device includes a random access preamble for transmission of the information on the CGI of the second neighbor cell. The terminal device transmits the information on the CGI of the second neighbor cell by: transmitting the random access preamble to the network device; and in response to receiving DCI indicating a resource for transmission of the information on the CGI of the second neighbor cell, transmitting the information on the CGI of the second neighbor cell based on the resource.

In some embodiments, the message received from the network device includes a random access preamble for transmission of the information on the CGI of the second neighbor cell. The terminal device transmits the information on the CGI of the second neighbor cell by: transmitting the random access preamble to the network device; and in response to receiving a random access response indicating a resource for transmission of the information on the CGI of the second neighbor cell and a timing advance command, transmitting the information on the CGI of the second neighbor cell based on the resource and the timing advance command.

FIG. 6 shows a flowchart of an example method 600 for neighbor cell measurement according to some embodiments of the present disclosure. The method 600 can be implemented at the network device 120 as shown in FIG. 1. It is to be understood that the method 600 may include additional blocks not shown and/or may omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

At block 610, a network device transmits, to a terminal device, a configuration to perform neighbor cell measurement during an idle mode, the network device providing at least a serving cell and a first neighbor cell.

In some embodiments, the configuration includes a RSRP threshold to trigger the neighbor cell measurement.

In some embodiments, the configuration includes a criterion to be satisfied by respective identities of a group of terminal devices for performing the neighbor cell measurement.

In some embodiments, the configuration includes control information on the neighbor cell measurement, and the control information on the neighbor cell measurement indicates at least one of the following: whether the neighbor cell measurement is to be performed; whether the result of the neighbor cell measurement is to be transmitted; timing information on the neighbor cell measurement; and a modification to a RSRP threshold for triggering the neighbor cell measurement.

In some embodiments, the configuration including the control information on the neighbor cell measurement is transmitted to the terminal device via any of the following: a Radio Resource Control (RRC) message transmitted on a paging occasion; and Downlink Control Information (DCI) transmitted on a paging occasion.

At block 620, the network device receives a result of the neighbor cell measurement from the terminal device, the result including at least a cell identity and signal quality of the first neighbor cell.

In some embodiments, the signal quality of the first neighbor cell includes at least one of the following: Reference Signal Received Power (RSRP) , Reference Signal Received Quality (RSRQ) and Relative Signal Strength Indication (RSSI) .

In some embodiments, the cell identity is a PCI, and the result of the neighbor cell measurement is received from the terminal device via a RRC message.

FIG. 7 shows a flowchart of an example method 700 for CGI reporting according to some embodiments of the present disclosure. The method 700 can be implemented at the network device 120 as shown in FIG. 1. For example, the method 700 can be implemented subsequent to or in parallel with the method 600. It is to be understood that the method 700 may include additional blocks not shown and/or may omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

At block 710, a network device transmits a message requesting a Cell Global identity (CGI) of a second neighbor cell to a terminal device, the message including a PCI of the second neighbor cell.

In some embodiments, the message transmitted to the terminal device includes one of the following: a RRC connection release message; and a fourth RRC message in MSG4 of a random access procedure.

In some embodiments, the network device transmits the message requesting the CGI of the second neighbor cell by: including a random access preamble for transmission of the information on the CGI of the second neighbor cell in the message; and transmitting the message to the terminal device.

At block 720, the network device receives the information on the CGI of the second neighbor cell from the terminal device.

In some embodiments, the network device receives the information on the CGI of the second neighbor cell by: in response to receiving the random access preamble from the terminal device, allocating a resource for transmission of the information on the CGI of the second neighbor cell; indicating the resource to the terminal device; and receiving, from the terminal device, the information on the CGI of the second neighbor cell based on the resource.

In some embodiments, the network device indicates the resource to the terminal device by: transmitting, to the terminal device, DCI indicating the resource.

In some embodiments, the network device indicates the resource to the terminal device by: transmitting, to the terminal device, a random access response indicating the resource and a timing advance command.

Embodiments of the present disclosure provide a solution for neighbor cell measurement and CGI reporting. In this solution, a terminal device can be selected for neighbor cell measurement and reporting in an idle mode, so as to reduce the impact of additional measurements from all of the terminal devices in the idle mode. The result of the neighbor cell measurement can be aligned to Discontinuous Reception (DRX) occasions, so as to distribute the uplink transmissions from a plurality of terminal devices. Dynamic control of the neighbor cell measurement and reporting through paging occasions can be enabled, so as to avoid redundant measurements by a plurality of terminal devices and avoid unnecessary transmissions from the plurality of terminal devices for sending similar measurement results. For CGI reporting, the network device can redirect the terminal device to idle mode to measure CGI for a selected PCI along with additional information, so as to enable CGI reporting in an energy efficient manner. Moreover, since the network device knows that the terminal device is expected to come back for CGI reporting, pre-allocation of the payload size for such reporting can be enabled, so as to further improve the efficiency of the transmission of the CGI report.

In some embodiments, an apparatus capable of performing the

method

400, 500, 600 and/or 700 may comprise means for performing the respective steps of the

method

400, 500, 600 and/or 700. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some embodiments, the apparatus capable of performing the method 400 (for example, the terminal device 110) comprises: means for receiving, from a network device, a configuration to perform neighbor cell measurement during an idle mode, the network device providing at least a serving cell and a first neighbor cell; means for determining, based on the configuration, whether the neighbor cell measurement is to be performed by the apparatus; means for measuring signal quality of the first neighbor cell during the idle mode in response to determining that the neighbor cell measurement is to be performed by the apparatus; and means for transmitting a result of the neighbor cell measurement to the network device, the result including a cell identity and the measured signal quality of the first neighbor cell.

In some embodiments, the apparatus capable of performing the method 500 (for example, the terminal device 110) comprises: means for obtaining, in response to receiving a message requesting a CGI of a second neighbor cell provided by a network device, information on the CGI of the second neighbor cell, the message including a PCI of the second neighbor cell; and means for transmitting the information on the CGI of the second neighbor cell to the network device.

In some embodiments, the apparatus capable of performing the method 600 (for example, the network device 120) comprises: means for transmitting, to a terminal device, a configuration to perform neighbor cell measurement during an idle mode, the apparatus providing at least a serving cell and a first neighbor cell; and means for receiving a result of the neighbor cell measurement from the terminal device, the result including at least a cell identity and signal quality of the first neighbor cell.

In some embodiments, the apparatus capable of performing the method 700 (for example, the network device 120) comprises: means for transmitting, to a terminal device, a message requesting a CGI of a second neighbor cell provided by the apparatus, the message including a PCI of the second neighbor cell; and means for receiving the information on the CGI of the second neighbor cell from the terminal device.

In some embodiments, the means comprises at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.

FIG. 8 is a simplified block diagram of a device 800 that is suitable for implementing embodiments of the present disclosure. The device 800 can be considered as an example implementation of the network device 120 or the terminal device 110 as shown in FIG. 1. Accordingly, the device 800 can be implemented at or as at least a part of the network device 120 or the terminal device 110.

As shown, the device 800 includes a processor 810, a memory 820 coupled to the processor 810, a suitable transmitter (TX) and receiver (RX) 840 coupled to the processor 810, and a communication interface coupled to the TX/RX 840. The memory 820 stores at least a part of a program 830. The TX/RX 840 is for bidirectional communications. The TX/RX 840 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements.

The program 830 is assumed to include program instructions that, when executed by the associated processor 810, enable the device 800 to operate in accordance with the implementations of the present disclosure, as discussed herein with reference to Figs. 2 to 7. The implementations herein may be implemented by computer software executable by the processor 810 of the device 800, or by hardware, or by a combination of software and hardware. The processor 810 may be configured to implement various implementations of the present disclosure. Furthermore, a combination of the processor 810 and memory 820 may form processing means 850 adapted to implement various implementations of the present disclosure.

The memory 820 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 820 is shown in the device 800, there may be several physically distinct memory modules in the device 800. The processor 810 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

The components included in the apparatuses and/or devices of the present disclosure may be implemented in various manners, including software, hardware, firmware, or any combination thereof. In one embodiment, one or more units may be implemented using software and/or firmware, for example, machine-executable instructions stored on the storage medium. In addition to or instead of machine-executable instructions, parts or all of the units in the apparatuses and/or devices may be implemented, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs) , Application-specific Integrated Circuits (ASICs) , Application-specific Standard Products (ASSPs) , System-on-a-chip systems (SOCs) , Complex Programmable Logic Devices (CPLDs) , and the like.

Generally, various embodiments of the present 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 embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method 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 those included in program modules, being executed in a device on a target real or virtual processor, to carry out the method 400 as described above with reference to FIG. 4, the method 500 as described above with reference to FIG. 5, the method 600 as described above with reference to FIG. 6, or the method 700 as described above with reference to FIG. 7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like 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 a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out 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 program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a 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.

In the context of the present disclosure, the computer program codes or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable media.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but 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 the computer readable storage medium would 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.

For the purpose of the present disclosure as described herein above, it should be noted that,

- method steps likely to be implemented as software code portions and being run using a processor at a network element or terminal (as examples of devices, apparatuses and/or modules thereof, or as examples of entities including apparatuses and/or modules therefore) , are software code independent and can be specified using any known or future developed programming language as long as the functionality defined by the method steps is preserved;

- generally, any method step is suitable to be implemented as software or by hardware without changing the idea of the invention in terms of the functionality implemented;

- method steps and/or devices, units or means likely to be implemented as hardware components at the above-defined apparatuses, or any module (s) thereof, (e.g., devices carrying out the functions of the apparatuses according to the embodiments as described above, eNode-B etc. as described above) are hardware independent and can be implemented using any known or future developed hardware technology or any hybrids of these, such as MOS (Metal Oxide Semiconductor) , CMOS (Complementary MOS) , BiMOS (Bipolar MOS) , BiCMOS (Bipolar CMOS) , ECL (Emitter Coupled Logic) , TTL (Transistor-Transistor Logic) , etc., using for example ASIC (Application Specific IC (Integrated Circuit) ) components, FPGA (Field-programmable Gate Arrays) components, CPLD (Complex Programmable Logic Device) components or DSP (Digital Signal Processor) components;

- devices, units or means (e.g. the above-defined apparatuses, or any one of their respective means) can be implemented as individual devices, units or means, but this does not exclude that they are implemented in a distributed fashion throughout the system, as long as the functionality of the device, unit or means is preserved;

- an apparatus may be represented by a semiconductor chip, a chipset, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of an apparatus or module, instead of being hardware implemented, be implemented as software in a (software) module such as a computer program or a computer program product comprising executable software code portions for execution/being run on a processor;

- a device may be regarded as an apparatus or as an assembly of more than one apparatus, whether functionally in cooperation with each other or functionally independently of each other but in a same device housing, for example.

It is noted that the embodiments and examples described above are provided for illustrative purposes only and are in no way intended that the present invention is restricted thereto. Rather, it is the intention that all variations and modifications be included which fall within the spirit and scope of the appended claims.

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 certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present 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 may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present 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.

Various embodiments of the techniques have been described. In addition to or as an alternative to the above, the following examples are described. The features described in any of the following examples may be utilized with any of the other examples described herein.

Claims

A method implemented at a terminal device, comprising:

receiving, from a network device, a configuration to perform neighbor cell measurement during an idle mode, the network device providing at least a serving cell and a first neighbor cell;

determining, based on the configuration, whether the neighbor cell measurement is to be performed by the terminal device;

in response to determining that the neighbor cell measurement is to be performed by the terminal device, measuring signal quality of the first neighbor cell during the idle mode; and

transmitting a result of the neighbor cell measurement to the network device, the result including a cell identity and the measured signal quality of the first neighbor cell.
The method of claim 1, wherein the configuration includes a Reference Signal Received Power (RSRP) threshold to trigger the neighbor cell measurement, and wherein determining whether the neighbor cell measurement is to be performed by the terminal device comprises:

measuring RSRP of the serving cell; and

in response to the measured RSRP of the serving cell being below the RSRP threshold, determining that the neighbor cell measurement is to be performed by the terminal device.
The method of claim 1, wherein the configuration includes a criterion to be satisfied by respective identities of a group of terminal devices for performing the neighbor cell measurement, and wherein determining whether the neighbor cell measurement is to be performed by the terminal device comprises:

in response to an identity of the terminal device satisfying the criterion, determining that the neighbor cell measurement is to be performed by the terminal device.
The method of claim 1, wherein the configuration includes control information on the neighbor cell measurement, and the control information on the neighbor cell measurement indicates at least one of the following:

whether the neighbor cell measurement is to be performed;

whether the result of the neighbor cell measurement is to be transmitted;

timing information on the neighbor cell measurement; and

a modification to a RSRP threshold for triggering the neighbor cell measurement.
The method of claim 4, wherein the configuration including the control information on the neighbor cell measurement is received from the network device via any of the following:

a Radio Resource Control (RRC) message transmitted on a paging occasion; and

Downlink Control Information (DCI) transmitted on a paging occasion.
The method of claim 4, wherein determining whether the neighbor cell measurement is to be performed by the terminal device comprises:

in response to the control information on the neighbor cell measurement indicating that the neighbor cell measurement is to be performed, determining that the neighbor cell measurement is to be performed by the terminal device.
The method of claim 4, wherein measuring the signal quality of the first neighbor cell comprises:

in response to the control information indicating the timing information on the neighbor cell measurement, measuring the signal quality of the first neighbor cell based on the timing information.
The method of claim 4, wherein transmitting the result of the neighbor cell measurement comprises:

in response to the control information on the neighbor cell measurement indicating that the result of the neighbor cell measurement is to be transmitted, transmitting the result of the neighbor cell measurement to the network device.
The method of claim 1, wherein the signal quality measured for the first neighbor cell includes at least one of the following:

Reference Signal Received Power (RSRP) ;

Reference Signal Received Quality (RSRQ) ; and

Relative Signal Strength Indication (RSSI) .
The method of any of claims 1, wherein the cell identity includes at least one of the following:

a Physical Cell Identity (PCI) ; and

a Cell Global identity (CGI) .
The method of any of claims 1, wherein the cell identity is a Physical Cell Identity (PCI) , and wherein transmitting the result of the neighbor cell measurement comprises:

transmitting the result of the neighbor cell measurement via a RRC message.
The method of claim 11, wherein the RRC message includes one of the following:

a first RRC message in Message 3 (MSG3) of a random access procedure;

a second RRC message in Message 5 (MSG5) of the random access procedure; and

a third RRC message subsequent to MSG5 of the random access procedure.
The method of any of claims 1-12, further comprising:

in response to receiving, from the network device, a message requesting a Cell Global identity (CGI) of a second neighbor cell provided by the network device, obtaining information on the CGI of the second neighbor cell, the message including a PCI of the second neighbor cell; and

transmitting the information on the CGI of the second neighbor cell to the network device.
The method of claim 13, wherein obtaining the information on the CGI of the second neighbor cell comprises:

entering the idle mode to synchronize to the second neighbor cell;

obtaining the information on the CGI of the second neighbor cell during the idle mode; and

returning back to the serving cell.
The method of claim 13, wherein the message received from the network device includes one of the following:

a RRC connection release message; and

a fourth RRC message in Message 4 (MSG4) of a random access procedure.
The method of claim 13, wherein the message received from the network device includes a random access preamble for transmission of the information on the CGI of the second neighbor cell, and wherein transmitting the information on the CGI of the second neighbor cell comprises:

transmitting the random access preamble to the network device; and

in response to receiving DCI indicating a resource for transmission of the information on the CGI of the second neighbor cell, transmitting the information on the CGI of the second neighbor cell based on the resource.
The method of claim 13, wherein the message received from the network device includes a random access preamble for transmission of the information on the CGI of the second neighbor cell, and wherein transmitting the information on the CGI of the second neighbor cell comprises:

transmitting the random access preamble to the network device; and

in response to receiving a random access response indicating a resource for transmission of the information on the CGI of the second neighbor cell and a timing advance command, transmitting the information on the CGI of the second neighbor cell based on the resource and the timing advance command.
A method implemented at a network device, comprising:

transmitting, to a terminal device, a configuration to perform neighbor cell measurement during an idle mode, the network device providing at least a serving cell and a first neighbor cell; and

receiving a result of the neighbor cell measurement from the terminal device, the result including at least a cell identity and signal quality of the first neighbor cell.
The method of claim 18, wherein the configuration includes a Reference Signal Received Power (RSRP) threshold to trigger the neighbor cell measurement.
The method of claim 18, wherein the configuration includes a criterion to be satisfied by respective identities of a group of terminal devices for performing the neighbor cell measurement.
The method of claim 18, wherein the configuration includes control information on the neighbor cell measurement, and wherein the control information on the neighbor cell measurement indicates at least one of the following:

whether the neighbor cell measurement is to be performed;

whether the result of the neighbor cell measurement is to be transmitted;

timing information on the neighbor cell measurement; and

a modification to a RSRP threshold for triggering the neighbor cell measurement.
The method of claim 21, wherein the configuration including the control information on the neighbor cell measurement is transmitted to the terminal device via any of the following:

a Radio Resource Control (RRC) message transmitted on a paging occasion; and

Downlink Control Information (DCI) transmitted on a paging occasion.
The method of any of claims 18, wherein the cell identity includes at least one of the following:

a Physical Cell Identity (PCI) ; and

a Cell Global identity (CGI) .
The method of any of claims 18, wherein the signal quality of the first neighbor cell includes at least one of the following:

Reference Signal Received Power (RSRP) ;

Reference Signal Received Quality (RSRQ) ; and

Relative Signal Strength Indication (RSSI) .
The method of claim 18, wherein the cell identity is a Physical Cell Identity (PCI) , and wherein receiving the result of the neighbor cell measurement comprises:

receiving the result of the neighbor cell measurement from the terminal device via a RRC message.
The method of claim 25, wherein the RRC message includes one of the following:

a first RRC message in Message 3 (MSG3) of a random access procedure;

a second RRC message in Message 5 (MSG5) of the random access procedure; and

a third RRC message subsequent to MSG5 of the random access procedure.
The method of any of claims 18-26, further comprising:

transmitting, to the terminal device, a message requesting a Cell Global identity (CGI) of a second neighbor cell provided by the network device, the message including a PCI of the second neighbor cell; and

receiving the information on the CGI of the second neighbor cell from the terminal device.
The method of claim 27, wherein the message transmitted to the terminal device includes one of the following:

a RRC connection release message; and

a fourth RRC message in Message 4 (MSG4) of a random access procedure.
The method of claim 27, wherein transmitting the message requesting the CGI of the second neighbor cell comprises:

including a random access preamble for transmission of the information on the CGI of the second neighbor cell in the message; and

transmitting the message to the terminal device.
The method of claim 27, wherein receiving the information on the CGI of the second neighbor cell comprises:

in response to receiving the random access preamble from the terminal device, allocating a resource for transmission of the information on the CGI of the second neighbor cell;

indicating the resource to the terminal device; and

receiving, from the terminal device, the information on the CGI of the second neighbor cell based on the resource.
The method of claim 30, wherein indicating the resource to the terminal device comprises:

transmitting, to the terminal device, DCI indicating the resource.
The method of claim 30, wherein indicating the resource to the terminal device comprises:

transmitting, to the terminal device, a random access response indicating the resource and a timing advance command.
A terminal device comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the terminal device to perform the method according to any of claims 1 to 17.
A network device comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the network device to perform the method according to any of claims 18 to 32.
An apparatus comprising:

means for receiving, from a network device, a configuration to perform neighbor cell measurement during an idle mode, the network device providing at least a serving cell and a neighbor cell;

means for determining, based on the configuration, whether the neighbor cell measurement is to be performed by the apparatus;

means for measuring signal quality of the neighbor cell during the idle mode in response to determining that the neighbor cell measurement is to be performed by the apparatus; and

means for transmitting a result of the neighbor cell measurement to the network device, the result including a cell identity and the measured signal quality of the neighbor cell.
The apparatus of claim 35, wherein the means comprises:

at least one processor; and

at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.
An apparatus comprising:

means for transmitting, to a terminal device, a configuration to perform neighbor cell measurement during an idle mode, the apparatus providing at least a serving cell and a neighbor cell; and

means for receiving a result of the neighbor cell measurement from the terminal device, the result including at least a cell identity and signal quality of the neighbor cell.
The apparatus of claim 37, wherein the means comprises:

at least one processor; and

at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.
A computer readable storage medium comprising program instructions stored thereon, the instructions, when executed by a processor of a device, causing the device to:

receive, from a network device, a configuration to perform neighbor cell measurement during an idle mode, the network device providing at least a serving cell and a neighbor cell;

determine, based on the configuration, whether the neighbor cell measurement is to be performed by the device;

in response to determining that the neighbor cell measurement is to be performed by the device, measure signal quality of the neighbor cell during the idle mode; and

transmit a result of the neighbor cell measurement to the network device, the result including a cell identity and the measured signal quality of the neighbor cell.
A computer readable storage medium comprising program instructions stored thereon, the instructions, when executed by a processor of a device, causing the device to:

transmit, to a terminal device, a configuration to perform neighbor cell measurement during an idle mode, the device providing at least a serving cell and a neighbor cell; and

receive a result of the neighbor cell measurement from the terminal device, the result including at least a cell identity and signal quality of the neighbor cell.