WO2021056459A1

WO2021056459A1 - Methods, devices, and medium for communication

Info

Publication number: WO2021056459A1
Application number: PCT/CN2019/108694
Authority: WO
Inventors: Gang Wang
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2019-09-27
Filing date: 2019-09-27
Publication date: 2021-04-01
Anticipated expiration: 2022-03-27

Abstract

Embodiments of the present disclosure relate to methods, devices, and medium for communication. A method for communication comprises determining, at a network device of a first communication network, first measurement configuration information for a terminal device that is out of a coverage area of a second communication network. The first measurement configuration information indicates a first measurement periodicity for first cell measurement on the second communication network, and the first measurement periodicity is at least being longer than a second measurement periodicity configurable to the terminal device in the second communication network. The method further includes transmitting the first measurement configuration information to the terminal device. This can save power and computation of the terminal device for performing meaningless cell measurement.

Description

METHODS, DEVICES, AND MEDIUM FOR COMMUNICATION

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to methods, devices, and medium for communication.

BACKGROUND

Communication technologies have been developed in various communication standards to provide a common protocol that enables different wireless devices to communicate with each other on a municipal, national, regional, and even global level. Mobility support is one of the fundamental features of any communication networks. In order to support mobility of a terminal device, the terminal device may continuously measure a quality of serving cell as well as a quality of neighboring cell. A measurement result may be used to decide whether the terminal device shall remain in the current cell or shall hand over or reselect to a neighboring cell. Measurement configuration is generally provided by a network device to the terminal device.

SUMMARY

In general, example embodiments of the present disclosure provide a solution of cell measurement configuration.

In a first aspect, there is provided a method for communication. The method comprises determining, at a network device of a first communication network, first measurement configuration information for a terminal device that is out of a coverage area of a second communication network, the first measurement configuration information indicating a first measurement periodicity for first cell measurement on the second communication network, the first measurement periodicity being at least being longer than a second measurement periodicity configurable to the terminal device in the second communication network; and transmitting the first measurement configuration information to the terminal device.

In a second aspect, there is provided a method for communication. The method comprises receiving, at a terminal device, first measurement configuration information from a network device of a first communication network, the terminal device being out of a coverage area of a second communication network, and the first measurement configuration information indicating a first measurement periodicity for first cell measurement on the second communication network, the first measurement periodicity being at least being longer than a second measurement periodicity configurable to the terminal device in the second communication network; and performing the first cell measurement based on the first measurement configuration information.

In a third aspect, there is provided a method for communication. The method comprises determining, at a transition network device, third measurement configuration information, the transition network device being located in a border area between coverage areas of a first and a second communication networks and operating with a first operating frequency that is different from a second operating frequency of the second communication network, the third measurement configuration information indicating the second operating frequency at which third cell measurement is to be performed by a terminal device; and transmitting the third measurement configuration information to the terminal device.

In a fourth aspect, there is provided a network device. The network device includes a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the device to perform the method according to the first aspect.

In a fifth aspect, there is provided a terminal device. The terminal device includes a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the device to perform the method according to the second aspect.

In a sixth aspect, there is provided a transition network device. The transition network device includes a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the device to perform the method according to the third aspect.

In a seventh aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to the first aspect.

In an eighth aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to the second aspect.

In a ninth aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to the third aspect.

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 example 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 is a signaling chart illustrating a process of cell measurement configuration according to an embodiment of the present disclosure;

Fig. 3 is a block diagram of a communication environment in which some example embodiments of the present disclosure can be implemented;

Fig. 4 is a signaling chart illustrating a process of cell measurement configuration according to a further embodiment of the present disclosure;

Fig. 5 is a flowchart of an example method in accordance with an embodiment of the present disclosure;

Fig. 6 is a flowchart of an example method in accordance with an embodiment of the present disclosure;

Fig. 7 is a flowchart of an example method in accordance with an embodiment 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 limitations 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.

As used herein, the term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an Evolved NodeB (eNodeB or eNB) , a NodeB in new radio access (gNB) a Remote Radio Unit (RRU) , a radio head (RH) , a remote radio head (RRH) , a low power node such as a femto node, a pico node, a satellite network device, an aircraft network device, and the like. For the purpose of discussion, in the following, some example embodiments will be described with reference to eNB as examples of the network device.

As used herein, the term “terminal device” refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, or image capture devices such as digital cameras, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

In one embodiment, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In one embodiment, the first network device may be a first RAT device and the second network device may be a second RAT device. In one embodiment, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device and the second network device. In one embodiment, first information may be transmitted to the terminal device from the first network device and second information may be transmitted to the terminal device from the second network device directly or via the first network device. In one embodiment, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

Communications discussed herein may use conform to any suitable standards including, but not limited to, New Radio Access (NR) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , cdma2000, and Global System for Mobile Communications (GSM) and the like. Furthermore, the communications may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols. The techniques described herein may be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies.

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 “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as “best, ” “lowest, ” “highest, ” “minimum, ” “maximum, ” or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

Fig. 1 shows an example communication environment in which implementations of the present disclosure can be implemented. In the example of Fig. 1, two types of communication networks are shown, including a communication network 101 (sometimes referred to as a “first communication network” ) and a communication network 102 (sometimes referred to as a “second communication network” ) . The communication network 101 is a non-terrestrial network (NTN) or non-ground network with one or more NTN network devices or non-ground network devices for providing communication coverage. The communication network 102 is a terrestrial network (TN) or ground network with one or more terrestrial or ground network devices for providing communication coverage.

As shown, the communication network 102 includes network devices 120-1, 120-2 (collectively or individually referred to as network devices 120) , which are also called terrestrial or ground network devices. The network devices 120 normally have respective coverage areas in which one or more terminal devices 110-1, 110-2 (collectively or individually referred to as terminal devices 110) can be served. The coverage areas of the network devices 120-1, 120-2 are also referred to as cells 122-1, 122-2 (collectively or individually referred to as cells 122) . The coverage areas of all the network devices 120 in the communication network 102 are considered as a coverage area of the communication network 102.

Terrestrial network devices, including the network devices 120, are generally installed at various earth-based locations to support communication services for the terminal device 110. From at least a cost perspective, terrestrial network devices are usually deployed in areas where the population is sufficient to justify the cost. There are many large areas of the planet where coverage from terrestrial network devices cannot be obtained. For example, in physically inhospitable areas such as the open ocean, dessert regions, jungles, and/or regions which are covered by ice sheets it may be difficult or impractical to deploy and maintain a terrestrial network device. The lack of network devices in some terrestrial regions leads to “dead zones. ”

As an alternative to terrestrial network devices, NTN network devices in the communication network 101 can provide necessary wireless communications for the terminal device 120 in areas where the signals from the terrestrial network devices are lost. As shown in Fig. 1, the communication network 101 includes a network device 130 which is a non-terrestrial network device. The network device 130 may be any network device floating in the air, such as a satellite network device, an aircraft (an aerial vehicle) or drone, or the like. The network device 130 may have a certain coverage area 132 which is generally much larger than a coverage area 122 of a network device 120. The coverage areas of all the network devices 130 in the communication network 101 are considered as a coverage area of the communication network 101.

Due to the high cost of the NTN network devices and generally low-quality and limited communication services provided by the NTN, a terminal device 110 connects to the network device 130 only if it is out of coverage of the terrestrial network 102. For example, the terminal device 110-2, which is carried by a user in the vessel, is out of service by the communication network 101 and can communicate with the network device 130 in the communication network 102.

Communications in the

communication networks

101 and 102 may be implemented according to any proper communication protocol (s) . Communication in a direction from a terminal device 110 towards a network device 120 or a network device 130 is referred to as uplink (UL) communication, while communication in a reverse direction from the network device 120 or the network device 130 towards the terminal device 110 is referred to as downlink (DL) communication.

In general, a mobility support for the terminal device 110 is a necessity factor in the wireless communication environment. In order to support the mobility of the terminal device 110, the terminal device 110 may continuously perform cell measurement in order to measure a quality of a serving cell providing a current service as well as a quality of a neighboring cell. Then, the measurement result may be used to decide whether the terminal device 110 shall be handed over to or re-selected to a different cell from the current cell.

For example, in the example of Fig. 1, the terminal device 110-1 is currently served by the network device 120-1. The terminal device 110-1 may detect and measure received signal strength of the network device 120-2 in the neighboring cell 122-2. For a terminal device moving out of coverage of the communication network 101, such as the terminal device 110-2, it may also perform cell measurement to decide which network device of the communication network 102 can serve or whether it is possible to switch to be served by a network device 120 of the communication network 101. The terminal device which is capable of communicating with the communication network 101 may also be referred to as a NTN-enabled terminal device.

In the terrestrial network, a terminal device can determine it is near the edge of a cell due to the near-far effect, i.e., a significant difference in received signal strength in the center of the cell as compared to the cell edge. Such an effect may not be as pronounced in the non-terrestrial deployment as the difference in signal strengths between two beams in overlap region may be low.

It is to be understood that the respective numbers of the network devices and terminal devices, as shown in Fig. 1, are provided merely for illustration, without any intention for limitation. In either the

communication network

101 or 102, there may be included any respective appropriate numbers of network devices and terminal devices. For example, the communication network 101 may include more than one network device similar to the network device 130.

Currently, configurations for cell measurement in the terrestrial network have been specified. However, in cases where a terminal device is moving across different types of communication networks, it would be beneficial to specially design the configuration of the cell measurement, especially by considering some special scenarios. For example, in some scenarios, e.g. when a vessel is sailing in the ocean, the terrestrial network device is very far from terminal devices of sailors, which means the terminal devices is impossible to handover from a non-terrestrial network device to a terrestrial network device for a long time. In this case, measurement of neighboring terrestrial network device is in vain and battery standby time of the terminal devices will be reduced due to the measurement.

According to example embodiments of the present disclosure, there is proposed a solution for cell measurement configuration in cross-network mobility. In this solution, if a terminal device is out of a coverage area of a communication network (such as a terrestrial network) but is within a coverage area of a further communication network (such as a non-terrestrial network) , a network device of the further communication network configure the terminal device with a relatively long measurement periodicity for cell measurement of the terminal device on the previous communication network. As such, the terminal device, when being out of a coverage area of a communication network such as the terrestrial network, can infrequently measure that communication network or even deactivate the measurement in areas where it is impossible to connect to that communication network. This can save power and computation of the terminal device for performing meaningless cell measurement.

Some example embodiments of the present disclosure will be described in detail below. Reference is first made to Fig. 2, which shows a signaling chart illustrating a process 200 of cell measurement configuration according to some example embodiments of the present disclosure. For the purpose of discussion, the process 200 will be described with reference to Fig. 1. The process 200 may involve a terminal device 110, a network device 130 of a communication network 101, and a network device 120 of a communication network 102 in Fig. 1.

In operation, the network device 130 of the communication network 101 determines 210 measurement configuration information for a terminal device 110 that is out of a coverage area of the communication network 102. For ease of discussion, the measurement configuration information is referred to as first measurement configuration information. The first measurement configuration information indicates one or more measurement parameters for cell measurement of the terminal device 110 on the communication network 102, including a measurement periodicity for the cell measurement (referred to a “first measurement periodicity” ) . The cell measurement here is referred to as “first cell measurement. ” A measurement periodicity indicates how frequently the cell measurement is performed by the terminal device 110. According to example embodiments of the present disclosure, the first measurement periodicity configured by the network device 130 in the communication network 101 is set to be at least longer than a measurement periodicity (referred to as a “second measurement periodicity” ) configurable to the terminal device 110 in the communication network 102.

In some example embodiments, it is assumed that the second measurement periodicity configurable to the terminal device 110 is selected by a network device 120 from a set of candidate measurement intervals {ms120, ms240, ms480, ms640, ms1024, ms2048, ms5120, ms10240, ms20480, ms40960, min1, min6, min12, min30} , where msX represents X ms, and minX represents X minutes. The first measurement periodicity may be selected from a set of candidate measurement intervals {hr1, hr3, hr6, hr12, day1, day3, day6, ect. } , where hrX represents X hours, and dayX represents X days. If the first measurement periodicity is set to be a measurement interval of 6 days, it means that the terminal device 110 will perform the first cell measurement every 6 days. It is to be understood that the above measurement intervals are enumerated merely for purpose of illustration and any other measurement intervals are also possible.

In some example embodiments, the first measurement periodicity may be configured to be deactivation of the first cell measurement, which is to instruct the terminal device 110 to deactivate or disable cell measurement on the communication network 102 as the terminal device 110 is out of any cells 122 of the communication network 102. The deactivation of the first cell measurement may be indicated by providing an indicator of deactivation (for example, represented as “disabled” ) or by removing a measurement object associated with the first cell measurement of the communication network 102. The deactivation of the first cell measurement may be considered as longer than any other configurable measurement intervals.

In addition to the first measurement periodicity, the first measurement configuration information may include one or more other measurement parameters that are required for the first cell measurement on the communication network 102. For example, the first measurement configuration information may additionally include one or more operating frequencies or operating bands used in the communication network 102 such that the terminal device 110 may search a signal transmitted from a certain network device 120 at the frequencies or frequency bands when performing the first cell measurement.

In some example embodiments, the network device 130 may determine the first measurement configuration information, especially the first measurement periodicity based on location information of the terminal device 110. The location information of the terminal device 110 may be reported by the terminal device 110, for example, during an initial attachment procedure that is performed when the terminal device 110 detects loss of signaling of a currently serving network device 120 of the communication network 101. As specific example, the terminal device 110 may include its location information in a RRCSetupComplete message transmitted to the network device 130. In other examples, the network device 130, upon establishing a network connection (such as a RRC connection) with the terminal device 110, may also request the terminal device 110 to report its location information.

The network device 130 may determine in which are the terminal device 110 is currently located based on the location information. In some scenarios such as a jungle, a national park, a gobi or desert region, the signaling of the network devices 120 in the communication network 102 may probably cover only part of areas, the terminal device 110 may spend minutes or hours to retrieve the terrestrial network devices 120, and the signaling of terrestrial network devices 120 may only last for minutes or hours. In some scenarios such as ocean sailing, a vessel may take days, weeks, or even months from a harbor to another harbor.

The network device 130 may configure a longer measurement periodicity for the first cell measurement on the communication network 102 if it determines that the terminal device 110 is located in an area that is known to be a “dead zone” and where the terminal device is known to be unlikely to search any signal from a network device 120 of the communication network 102. Such area may be one of an ocean, a jungle, a national park, a gobi or desert region, and/or any other area where a terrestrial network device is difficult or impractical to be deployed.

In some example embodiments, depending on different areas where the terminal device 110 is located, the first measurement periodicity may be configured to different. Specifically, if the network device 130 determines that the terminal device 110 is located in a first area that is more far away from the coverage area of the communication network 102 than a second area, the network device 130 may the first measurement configuration information to indicate the first measurement periodicity as being longer than a measurement periodicity (referred to as a “third measurement periodicity” ) that is configurable to a terminal device 110 located in the second area. That is to say, the more far away from the coverage area of the communication network 102 the terminal device 110 is located, the longer the measurement periodicity is configured. As an example, the measurement periodicity configured for a terminal device 110 located in an open ocean may be configured as longer than the measurement periodicity configured for a terminal device 110 located in a national park.

In some example embodiments, there is a predetermined mapping between measurement periodicities and specific geographic areas. The network device 130 may determine the first measurement periodicity configured for the terminal device 110 based on such mapping and the actual location information of the terminal device 110.

In some example embodiments, the network device 130 may gradually increase the measurement periodicity used by the terminal device 110. In determining the first measurement configuration information, the network device 130 may receive, from the terminal device 110, a first measurement result of the first cell measurement that is performed based on a previously-configured measurement periodicity (sometime referred to as a “fourth measurement periodicity” for ease of description) . In this case, the terminal device 110 may be in a connected mode with the network device 130 and thus can report the measurement result to the network device 130.

If the first received measurement result indicates that during the first cell measurement performed according to the fourth measurement result, the terminal device 110 fails to detect any signal from a cell 122 (i.e., a network device 120) of the communication network 102 or only detects a week signal (the received signal strength of which fails to satisfy a strength criterion) , the network device 130 may set the first measurement periodicity, which is currently to be configured to the terminal device 110, to be longer than the previously-configured fourth measurement periodicity. For example, if the network device 130 first configures a measurement periodicity of one hour to the terminal device 110 and the terminal device 110 reports a measurement result indicating a failure of searching any signal from the communication network 102 in the cell measurement performed according to that measurement periodicity. Due to such measurement result, the network device 130 may increase the measurement periodicity to be one day and configure such measurement periodicity in the measurement configuration information. After one or several times of attempts, the network device 130 may determines that the terminal device 110 is currently located in a large “dead zone” and may configure its measurement periodicity to be a much larger value or may even deactivate the cell measurement on the communication network 102.

Instead of configuring incremental measurement configuration information step by step, in some example embodiments, the network device 130 may determine the first measurement configuration information to indicate a set of incremental measurement periodicities and a set of timers associated with the set of incremental measurement periodicities, the set of incremental measurement periodicities comprising the first measurement periodicity. For example, the set of incremental measurement periodicities may include a set of candidate measurement intervals {hr1, hr3, hr 6, hr12, day1, day3, day6, ect. } and an indicator of deactivation of the first cell measurement {disable} .

In some examples, the set of incremental measurement periodicities may include one or more measurement periodicities that are configurable in the communication network 102. That is, in the embodiments of incremental measurement periodicities, the terminal device 110 may be allowed to start from a short measurement periodicity that is used in the communication network 102 and then increase the measurement periodicity in cases of failure of detecting any signal from the communication network 102.

The set of incremental measurement periodicities are selectable by the terminal device 110 for the first cell measurement. An associated timer for the measurement periodicity indicates how long the measurement periodicity is used for the first cell measurement. The configuration of the incremental measurement periodicities may be beneficial when the network device 130 cannot obtain the location information of the terminal device 110. For example, when the terminal device 110 is in an idle mode within the coverage area 132, the network device 130 cannot be aware of the location information of the terminal device 110.

The network device 130 transmits 220 the first measurement configuration information to the terminal device 110. The network device 130 may transmit the first measurement configuration information to the terminal device 110 in various manners. In some example embodiments, the first measurement configuration information may be broadcasted or groupcasted to the terminal device 110. For example, the first measurement configuration information may be included in system information (SI) and then broadcasted by the network device 130. The terminal device 110, when disconnecting from the network device 120 and being within the coverage area of the network device 130, can receive the broadcasted or groupcasted first measurement configuration information. In such case, the terminal device 110 may be in an idle mode and has not established a network connection with the network device 130. In some example embodiments where the network connection is established, the network device 130 may transmit the first measurement configuration information via the network connection to the terminal device 110.

Upon receipt of the first measurement configuration information, the terminal device 110 performs 230 the first cell measurement on the communication network 102 based on the first measurement configuration information. Generally one or more network devices 120 in the communication network 102 may transmit a broadcast signal or a reference signal at its operating frequency or frequency band. The terminal device 110 can search for a signal detected from a network device 120 of the communication network 102 at the operating frequency or frequency band according to the measurement periodicity indicated in the first measurement configuration information.

If the terminal device 110 can successfully detect a signal from the communication network 102, it means that the terminal device 110 is approaching the coverage area of the communication network 102 (for example, a cell 122 of a network device 120) . If a strength of the received signal is high (for example, higher than a strength threshold) , the terminal device 110 may be handed over to or perform cell reselection to the network device 120.

The terminal device 110 may report the first measurement result of the first cell measurement (no matter whether the signal is detected) to the network device 130, for example, when the terminal device 110 is in a connected mode with the network device 130. In some cases, the terminal device 110 may not be required to report the first measurement result. As an example, in the cases of being in the idle mode, the terminal device 110 may not report the first measurement result but can use the first measurement result to decide whether to reselect a cell 122 of the network device 120 as its serving cell.

In some example embodiments where the first measurement configuration information indicates the set of incremental measurement periodicities and the set of timers associated, the terminal device 110 may start a first timer of the set of timers that is associated with a measurement periodicity selected from the set of incremental measurement periodicities. The terminal device 110 may perform cell measurement by detecting a signal from a cell of the communication network 102 based on the selected measurement periodicity before the first timer expires. If the terminal device 110 fails to detect the signal after the first timer expires, the terminal device 110 may start a second timer of the set of timers that is associated with another measurement periodicity selected the set of incremental measurement periodicities, the other measurement periodicity being longer than the previously-used measurement periodicity. The terminal device 110 may further detect the signal from the communication network 102 based on the selected measurement periodicity before the second timer expires. That is, the terminal device 110 may gradually increase the measurement periodicity used for the cell measurement. In some example embodiments, the terminal device 110 may end up with deactivation of the first cell measurement.

In some of the territorial areas, such as the gobi or jungle, the terminal device 110 may be suffering large pieces of coverage holes and the user carrying the terminal device 110 may randomly move in these areas, making the next cell 122 of the network device 120 of the communication network 102 is unpredictable. Occasional cell measurement on the communication 102 can facilitate the terminal device 110 to find the cell 122. In some scenarios, the next cell 122 where the coverage of the communication network 102 is provided is predictable. For example, for the ocean sailing, the harbor is the first place that the sailor can reach, which make this area a border area between the coverage areas of the two

communication networks

101 and 102. In such case, a transition network device may be deployed in in the border area.

Fig. 3 shows an example environment where a transition network device 310 is deployed in the communication environment of Fig. 1. For clarity, the communication network 102 is simplified to include one network device 120. The transition network device 310 may be deployed as being near to the coverage area of the communication network 102 (such as a cell 122 of the communication network 102) . The transition network device 310 may be configured to transition the terminal device 110 from the communication network 101 to the communication network 102.

The transition network device 310 may be deployed in the terrestrial area but operates at a frequency that is different from the operating frequency/frequencies or frequency band (s) of the communication network 102. Sometimes the operating frequency of the transition network device 310 is referred to as a first operating frequency and the operating frequency/frequencies or frequency band (s) of the communication network 102 may be referred to as a second operating frequency/frequencies or frequency band (s) . A serving area of the transition network device 310 may be referred to as a coverage area 312 or a cell of the transition network device 310.

In some example embodiments, the first operating frequency of the transition network device 310 may be comprised in an operating frequency range of the communication network 101. For example, the transition network device 310 may operate in a satellite frequency band of the communication network 101, such as a S-band or Ka-band. In some examples, the first operating frequency band is dedicated to the transition network device, such as a dedicated frequency band in the operating frequency range of the communication network 101 which is not used by other network devices in the communication network 101. As such, the terminal device 110 can detect the occurrence of the transition network device by performing cell measurement on the communication network 101 (referred to as “second cell measurement” ) .

It would be appreciated that although one transition network device is shown in Fig. 3, in other implementations, one or more other transition network devices may be deployed at terrestrial areas where the terminal devices 110 have a higher probability of reaching after travelling through the area out of the coverage of the communication network 102. The transition network devices may share the operating frequency range of the communication network 101 or may have dedicated frequencies in the frequency range.

With the introduction of the transition network device 310, possible interactions between the

network devices

120, 130, 310 and the terminal device 110 are shown in Fig. 4, which illustrates a signaling chart illustrating a process 400 of cell measurement configuration according to some other example embodiments of the present disclosure. For the purpose of discussion, the process 400 will be described with reference to Fig. 3. The process 400 may involve the terminal device 110, the network device 130 of the communication network 101, the transition network device 310, and the network device 120 of a communication network 102.

The network device 130 determines 410 measurement configuration information (referred to as “second measurement configuration information” for ease of description) . The second measurement configuration information at least indicates the first operating frequency of the transition network device 310. In some example embodiments, since the first operating frequency is a part of the operating range of the communication network 101, the second measurement configuration information may be normal measurement configuration information that is supposed to be provided to the terminal device 110 for measuring signals from the network device 130 and/or network devices in neighbor cells of the communication network 101. The terminal device may perform cell measurement on the communication network 101 (referred to as “second cell measurement” for ease of description) at the configured first operating frequency.

In addition to the first operating frequency, the second measurement configuration information may indicate other operating frequencies of one or more network devices 130 of the communication network 101. The second measurement configuration information may also indicate a measurement periodicity for the second cell measurement. Such measurement periodicity may be configured depending on the deployment of the network devices 130 in the communication network 101.

The network device 130 then transmits 420 the second measurement configuration information to the terminal device 110. The terminal device 110 performs 430 the second cell measurement based on the second measurement configuration information. Specifically, the terminal device 110 may try to detect a signal at the first operating frequency. A measurement result (referred to as a “second measurement result” ) of the second cell measurement may be used to decide whether the terminal device 110 is able to change to the transition network device 310.

The decision may be made by the terminal device 110, for example, when the terminal device 110 is in an idle mode, or may be made by the network device 130, for example, when the terminal device 110 is in a connected mode with the network device 130. The terminal device 110 may perform a cell-reselection procedure to the transition network device 310 if it is in the idle mode, or may perform a handover procedure from the network device 130 to the transition network device 310 if it is in the connected mode.

Specifically, if the terminal device 110 successfully detects a signal at the first operating frequency band and strength of the received signal satisfies a strength criterion, the terminal device 110 may determine to change to a network device from which the signal is received. In some cases the terminal device 110 may successfully detect signals from more than one network device. In order to make the terminal device 110 change to the transition network device 310, the transition network device 310 may transmit an indication of an identity of the transition network device 310, for example, in its system information. Upon receipt of the indication, the terminal device 110 in the idle mode may prioritize the transition network device 310 for cell reselection over other network devices in the communication network101. As such, when the terminal device 110 successfully detects satisfied signal transmitted from the transition network device 310 (for example, successfully receive the system information broadcasted from the transition network device 310) , the terminal device 110 may determine to perform a cell reselection to the transition network device 310 or may report to the network device 130 to request handover to the transition network device 310.

In some further embodiments, the first operating frequency of the transition network device 310 may be configured with a priority higher than priorities of other operating frequencies of network devices 130 in the communication network 101. As such, if the terminal device 110 in the idle mode receives a satisfied signal from the transition network device 310, the terminal device 110 may prioritize the transition network device 310 for cell reselection over the network device 130 in the communication network 101.

In some example embodiments where the terminal device 110 is in the connected mode with the network device 130, the terminal device 110 may transmit the second measurement result of the second cell measurement to the network device 130. The network device 130 may determine, based on the second measurement result, whether handover of the terminal device 110 to the transition network device 310 is available. If it is determined that the handover of the terminal device 110 is available, the network device 130 may trigger a handover of the terminal device 110 to the transition network device 310.

No matter whether the terminal device 110 or the network device 130 determines that handover or cell reselection of the terminal device 110 to the transition network device 310 is available, the terminal device 110 performs 440 the corresponding handover or cell-reselection procedure to the transition network device 310.

After the handover or cell-reselection of the terminal device 110 to the transition network device 310, the transition network device 310 determines 450 measurement configuration information (referred to as “third measurement configuration information” for ease of discussion) to indicate the second operating frequency at which third cell measurement is performed by a terminal device. The second operating frequency may include a frequency (frequencies) or frequency band (s) of the communication network 102 at which one or more network devices 120 is operating. Thus, the third cell measurement is performed on the communication network 102, similar as the first cell measurement.

In some cases, the transition network device 310 may specifically configure one or more operating frequencies of one or more network devices 120 near to the transition network device 310. The terminal device 110 may possibly connect to such network devices 120 first. In addition to the second operating frequency, the third measurement configuration information may additionally indicate a measurement periodicity for the third cell measurement.

The transition network device 310 transmits 460 the third measurement configuration information to the terminal device 110, for example, by means of broadcasting, groupcasting, and/or transmission via an established network connection with terminal device 110. Upon receipt of the third measurement configuration information, the terminal device 110 performs 470 the third cell measurement based on the third measurement configuration information. Specifically, the terminal device 110 may try to detect, at the second operating frequency, a signal transmitted from a network device 120 in the communication network 102. A measurement result (referred to as a “third measurement result” ) of the third cell measurement may be used to decide whether the terminal device 110 is able to change to a network device 120 in the communication network 102.

The decision may be made by the terminal device 110, for example, when the terminal device 110 is in an idle mode, or may be made by the network device 310, for example, when the terminal device 110 is in a connected mode with the network device 310. The terminal device 110 may perform a cell-reselection procedure to the network device 120 if it is in the idle mode, or may perform a handover procedure from the transition network device 310 to the network device 120 if it is in the connected mode. The handover or cell reselection is similar as that discussed with respect to the transition network device 310, and various criteria may be applied to determine whether the terminal device 110 can change to be served by the network device 120. The scope of the present disclosure is not limited in this regard.

With the introduction of the transition network device 310, the terminal device 110 can activate the cell measurement on the communication network 102 when it approaches the coverage area of this network 102. In other areas out of the coverage area of this network 102, the terminal device 110 may be configured to deactivate the cell measurement on the communication network 102, which may further save power and improve communication performance of the terminal device 110.

Fig. 5 shows a flowchart of an example method 500 in accordance with an embodiment of the present disclosure. The method 500 can be implemented at a network device 130 of a communication network 101 as shown in Fig. 1 and Fig. 3.

At block 510, the network device 130 determines first measurement configuration information for a terminal device that is out of a coverage area of a second communication network. The first measurement configuration information indicates a first measurement periodicity for first cell measurement on the second communication network, and the first measurement periodicity is at least being longer than a second measurement periodicity configurable to the terminal device in the second communication network. At block 520, the network device 130 transmits the first measurement configuration information to the terminal device.

In some example embodiments, the first measurement periodicity indicates one of a plurality of candidate measurement intervals or deactivation of the first cell measurement.

In some example embodiments, determining the first measurement configuration information comprises: obtaining location information of the terminal device; and determining the first measurement configuration information based on the location information.

In some example embodiments, determining the first measurement configuration information based on the location information comprises: in accordance with the location information indicating that the terminal device is located in a first area that is more far away from the coverage area of the second communication network than a second area, determining the first measurement configuration information to indicate the first measurement periodicity as being longer than a third measurement periodicity that is configurable to a further terminal device located in the second area.

In some example embodiments, obtaining the location information comprises: receiving the location information from the terminal device during an initial attachment procedure of the terminal device to the network device.

In some example embodiments, determining the first measurement configuration information comprises: receiving, from the terminal device, a first measurement result of the first cell measurement that is performed based on a fourth measurement periodicity; and in accordance with the first measurement result indicating a failure of detecting a signal from the second communication network, determining the first measurement configuration information to indicate the first measurement periodicity that is longer than the fourth measurement periodicity.

In some example embodiments, determining the first measurement configuration information comprises: determining the first measurement configuration information to indicate a set of incremental measurement periodicities selectable by the terminal device for the first cell measurement and a set of timers associated with the set of incremental measurement periodicities, the set of incremental measurement periodicities comprising the first measurement periodicity.

In some example embodiments, the method 500 further comprises determining second measurement configuration information to indicate a first operating frequency of a transition network device at which second cell measurement is performed, the transition network device being located near to the coverage area, and the first operating frequency being different from a second operating frequency of the second communication network; and transmitting the second measurement configuration information to the terminal device.

In some example embodiments, the first operating frequency is comprised in an operating frequency range of the first communication network or is dedicated to the transition network device.

In some example embodiments, the terminal device is in a connected mode with the network device, and the method 500 further comprises receiving a second measurement result of the second cell measurement; determining, based on the second measurement result, whether handover of the terminal device to the transition network device is available; and in accordance with a determination that the handover of the terminal device is available, triggering a handover of the terminal device to the transition network device.

In some example embodiments, transmitting the first measurement configuration information comprises: broadcasting the first measurement configuration information in system information; groupcasting the first measurement configuration information to the terminal device, or transmitting the first measurement configuration information via a network connection established with the terminal device.

In some example embodiments, the first communication network is a non-terrestrial network (NTN) , and the second communication network is a terrestrial network (TN) .

Fig. 6 shows a flowchart of an example method 600 in accordance with an embodiment of the present disclosure. The method 600 can be implemented at a terminal device 110 as shown in Fig. 1 and Fig. 3.

At block 610, the terminal device 110 receives first measurement configuration information from a network device of a first communication network. The terminal device 110 is out of a coverage area of a second communication network, and the first measurement configuration information indicates a first measurement periodicity for first cell measurement on the second communication network. The first measurement periodicity is at least being longer than a second measurement periodicity configurable to the terminal device in the second communication network. At block 620, the terminal device 110 performs the first cell measurement based on the first measurement configuration information.

In some example embodiments, the terminal device is located in a first area that is more far away from the coverage area of the second communication network than a second area, and the first measurement periodicity is determined as being longer than a third measurement periodicity that is configurable to a further terminal device located in the second area.

In some example embodiments, the method 600 further comprises transmitting, to the network device, location information of the terminal device during an initial attachment procedure of the terminal device to the network device.

In some example embodiments, the method 600 further comprises determining a first measurement result of the first cell measurement that is performed based on a fourth measurement periodicity, the first measurement result indicating a failure of detecting a signal from the second communication network; and transmitting the first measurement result to the network device. In some example embodiments, receiving the first measurement configuration information comprises receiving the first measurement configuration information indicating the first measurement periodicity that is longer than the fourth measurement periodicity.

In some example embodiments, receiving the first measurement configuration information comprises: receiving the first measurement configuration information that indicates a set of incremental measurement periodicities selectable by the terminal device for the first cell measurement and a set of timers associated with the set of incremental measurement periodicities, the set of incremental measurement periodicities comprising the first measurement periodicity. In some example embodiments, performing the first cell measurement comprises: starting a first timer of the set of timers that is associated with a fifth measurement periodicity of the set of incremental measurement periodicities, detecting a signal from the second communication network based on the fifth measurement periodicity before the first timer expires, in accordance with a determination of a failure of detecting the signal after the first timer expires, starting a second timer of the set of timers that is associated with a sixth measurement periodicity of the set of incremental measurement periodicities, the sixth measurement periodicity being longer than the fifth periodicity, and detecting the signal from the second communication network based on the sixth measurement periodicity before the second timer expires.

In some example embodiments, the method 600 further comprises receiving, from the network device, second measurement configuration information, the second measurement configuration information indicating a first operating frequency of a transition network device that is located near to the coverage area, and the first operating frequency being different from a second operating frequency of the second communication network; and performing second cell measurement based on the second measurement configuration information.

In some example embodiments, the method 600 further comprises determining whether handover or cell reselection of the terminal device to the transition network device is available based on a second measurement result of the second cell measurement; and in accordance with a determination that the handover or the cell reselection is available, performing a handover or cell-reselection procedure to the transition network device.

In some example embodiments, the terminal device is in an idle mode, and determining whether the handover or the cell reselection is available comprises: in accordance with the second measurement result indicating receipt of an identity of the transition network device from the transition network device, determining that the cell reselection to the transition network device is available; or in accordance with the first operating frequency being configured with a priority higher than priorities of a third operating frequency of the first communication network and the second measurement result indicating receipt of a signal from the transition network device, determining that the cell reselection to the transition network device is available.

In some example embodiments, the method 600 further comprises receiving, from the transition network device, third measurement configuration information indicating the second operating frequency; and performing third cell measurement based on the third measurement configuration information.

In some example embodiments, the method 600 further comprises determining whether handover or cell reselection of the terminal device to a further network device of the second communication network is available based on a third measurement result of the third cell measurement; and in accordance with a determination that the handover or the cell reselection to the further network device is available, performing a further handover or cell-reselection procedure to the further network device.

In some example embodiments, receiving the first measurement configuration information comprises: receiving the first measurement configuration information broadcasted in system information from the network device; receiving the first measurement configuration information groupcasted from the network device; or receiving the first measurement configuration information via a network connection established with the network device.

Fig. 7 shows a flowchart of an example method 700 in accordance with an embodiment of the present disclosure. The method 700 can be implemented at a network device 120 of a communication network 102 as shown in Fig. 1 and Fig. 3.

At block 710, the network device 120 determines third measurement configuration information, the transition network device being located in a border area between coverage areas of a first and a second communication networks and operating with a first operating frequency that is different from a second operating frequency of the second communication network, the third measurement configuration information indicating the second operating frequency at which third cell measurement is to be performed by a terminal device. At block 720, the network device 120 transmits the third measurement configuration information to the terminal device.

In some example embodiments, the terminal device is in an idle mode and the method 700 further comprises transmitting, to the terminal device, an indication of an identity of the transition network device in system information, such that the terminal device, upon receipt of the indication, prioritizes the transition network device for handover or cell reselection over a network device of the second communication network.

In some example embodiments, the first operating frequency is configured with a priority higher than priorities of a third operating frequency of the first communication network, such that the terminal device, upon receipt of a signal from the transition network device, prioritizes the transition network device for handover or cell reselection over a network device of the first communication network.

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 a further example implementation of the terminal device 110, the network device 120, the network device 130, or the transition network device 310 as shown in Fig. 1 and Fig. 3. Accordingly, the device 800 can be implemented at or as at least a part of the terminal device 110, the network device 120, the network device 130, or the transition network device 310.

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, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

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 embodiments of the present disclosure, as discussed herein with reference to Fig. 2 and Figs. 4 to 7. The embodiments 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 embodiments of the present disclosure. Furthermore, a combination of the processor 810 and memory 820 may form processing means 850 adapted to implement various embodiments 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.

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 representation, it will be appreciated 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 those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to any of Fig. 2 and Figs. 4 to 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.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may 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 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 machine 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.

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 language 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.

Claims

A method for communication comprising:

determining, at a network device of a first communication network, first measurement configuration information for a terminal device that is out of a coverage area of a second communication network, the first measurement configuration information indicating a first measurement periodicity for first cell measurement on the second communication network, the first measurement periodicity being at least being longer than a second measurement periodicity configurable to the terminal device in the second communication network; and

transmitting the first measurement configuration information to the terminal device.
The method of claim 1, wherein the first measurement periodicity indicates one of a plurality of candidate measurement intervals or deactivation of the first cell measurement.
The method of claim 1, wherein determining the first measurement configuration information comprises:

obtaining location information of the terminal device; and

determining the first measurement configuration information based on the location information.
The method of claim 3, wherein determining the first measurement configuration information based on the location information comprises:

in accordance with the location information indicating that the terminal device is located in a first area that is more far away from the coverage area of the second communication network than a second area,

determining the first measurement configuration information to indicate the first measurement periodicity as being longer than a third measurement periodicity that is configurable to a further terminal device located in the second area.
The method of claim 3, wherein obtaining the location information comprises:

receiving the location information from the terminal device during an initial attachment procedure of the terminal device to the network device.
The method of claim 1, wherein determining the first measurement configuration information comprises:

receiving, from the terminal device, a first measurement result of the first cell measurement that is performed based on a fourth measurement periodicity; and

in accordance with the first measurement result indicating a failure of detecting a signal from the second communication network, determining the first measurement configuration information to indicate the first measurement periodicity that is longer than the fourth measurement periodicity.
The method of claim 1, wherein determining the first measurement configuration information comprises:

determining the first measurement configuration information to indicate a set of incremental measurement periodicities selectable by the terminal device for the first cell measurement and a set of timers associated with the set of incremental measurement periodicities, the set of incremental measurement periodicities comprising the first measurement periodicity.
The method of claim 1, further comprising:

determining second measurement configuration information to indicate a first operating frequency of a transition network device at which second cell measurement is performed, the transition network device being located near to the coverage area, and the first operating frequency being different from a second operating frequency of the second communication network; and

transmitting the second measurement configuration information to the terminal device.
The method of claim 8, wherein the first operating frequency is comprised in an operating frequency range of the first communication network or is dedicated to the transition network device.
The method of claim 8, wherein the terminal device is in a connected mode with the network device, the method further comprising:

receiving a second measurement result of the second cell measurement;

determining, based on the second measurement result, whether handover of the terminal device to the transition network device is available; and

in accordance with a determination that the handover of the terminal device is available, triggering a handover of the terminal device to the transition network device.
The method of claim 1, wherein transmitting the first measurement configuration information comprises:

broadcasting the first measurement configuration information in system information;

groupcasting the first measurement configuration information to the terminal device, or

transmitting the first measurement configuration information via a network connection established with the terminal device.
The method of claim 1, wherein the first communication network is a non-terrestrial network (NTN) , and the second communication network is a terrestrial network (TN) .
A method for communication comprising:

receiving, at a terminal device, first measurement configuration information from a network device of a first communication network, the terminal device being out of a coverage area of a second communication network, and the first measurement configuration information indicating a first measurement periodicity for first cell measurement on the second communication network, the first measurement periodicity being at least being longer than a second measurement periodicity configurable to the terminal device in the second communication network; and

performing the first cell measurement based on the first measurement configuration information.
The method of claim 13, wherein the first measurement periodicity indicates one of a plurality of candidate measurement intervals or deactivation of the first cell measurement.
The method of claim 13, wherein the terminal device is located in a first area that is more far away from the coverage area of the second communication network than a second area, and the first measurement periodicity is determined as being longer than a third measurement periodicity that is configurable to a further terminal device located in the second area.
The method of claim 13, further comprising:

transmitting, to the network device, location information of the terminal device during an initial attachment procedure of the terminal device to the network device.
The method of claim 13, further comprising:

determining a first measurement result of the first cell measurement that is performed based on a fourth measurement periodicity, the first measurement result indicating a failure of detecting a signal from the second communication network; and

transmitting the first measurement result to the network device, and

wherein receiving the first measurement configuration information comprises receiving the first measurement configuration information indicating the first measurement periodicity that is longer than the fourth measurement periodicity.
The method of claim 13, wherein receiving the first measurement configuration information comprises:

receiving the first measurement configuration information that indicates a set of incremental measurement periodicities selectable by the terminal device for the first cell measurement and a set of timers associated with the set of incremental measurement periodicities, the set of incremental measurement periodicities comprising the first measurement periodicity; and

wherein performing the first cell measurement comprises:

starting a first timer of the set of timers that is associated with a fifth measurement periodicity of the set of incremental measurement periodicities,

detecting a signal from the second communication network based on the fifth measurement periodicity before the first timer expires,

in accordance with a determination of a failure of detecting the signal after the first timer expires, starting a second timer of the set of timers that is associated with a sixth measurement periodicity of the set of incremental measurement periodicities, the sixth measurement periodicity being longer than the fifth periodicity, and

detecting the signal from the second communication network based on the sixth measurement periodicity before the second timer expires.
The method of claim 13, further comprising:

receiving, from the network device, second measurement configuration information, the second measurement configuration information indicating a first operating frequency of a transition network device that is located near to the coverage area, and the first operating frequency being different from a second operating frequency of the second communication network; and

performing second cell measurement based on the second measurement configuration information.
The method of claim 19, wherein the first operating frequency is comprised in an operating frequency range of the first communication network or is dedicated to the transition network device.
The method of claim 19, further comprising:

determining whether handover or cell reselection of the terminal device to the transition network device is available based on a second measurement result of the second cell measurement; and

in accordance with a determination that the handover or the cell reselection is available, performing a handover or cell-reselection procedure to the transition network device.
The method of claim 21, wherein the terminal device is in an idle mode, and determining whether the handover or the cell reselection is available comprises:

in accordance with the second measurement result indicating receipt of an identity of the transition network device from the transition network device, determining that the cell reselection to the transition network device is available; or

in accordance with the first operating frequency being configured with a priority higher than priorities of a third operating frequency of the first communication network and the second measurement result indicating receipt of a signal from the transition network device, determining that the cell reselection to the transition network device is available.
The method of claim 21, further comprising:

receiving, from the transition network device, third measurement configuration information indicating the second operating frequency; and

performing third cell measurement based on the third measurement configuration information.
The method of claim 23, further comprising:

determining whether handover or cell reselection of the terminal device to a further network device of the second communication network is available based on a third measurement result of the third cell measurement; and

in accordance with a determination that the handover or the cell reselection to the further network device is available, performing a further handover or cell-reselection procedure to the further network device.
The method of claim 13, wherein receiving the first measurement configuration information comprises:

receiving the first measurement configuration information broadcasted in system information from the network device;

receiving the first measurement configuration information groupcasted from the network device; or

receiving the first measurement configuration information via a network connection established with the network device.
The method of any of claims 13 to 25, wherein the first communication network is a non-terrestrial network (NTN) , and the second communication network is a terrestrial network (TN) .
A method for communication comprising:

determining, at a transition network device, third measurement configuration information, the transition network device being located in a border area between coverage areas of a first and a second communication networks and operating with a first operating frequency that is different from a second operating frequency of the second communication network, the third measurement configuration information indicating the second operating frequency at which third cell measurement is to be performed by a terminal device; and

transmitting the third measurement configuration information to the terminal device.
The method of claim 27, wherein the first operating frequency is comprised in an operating frequency range of the first communication network or is dedicated to the transition network device.
The method of claim 27, wherein the terminal device is in an idle mode, the method further comprising:

transmitting, to the terminal device, an indication of an identity of the transition network device in system information, such that the terminal device, upon receipt of the indication, prioritizes the transition network device for handover or cell reselection over a network device of the second communication network.
The method of claim 27, wherein the first operating frequency is configured with a priority higher than priorities of a third operating frequency of the first communication network, such that the terminal device, upon receipt of a signal from the transition network device, prioritizes the transition network device for handover or cell reselection over a network device of the first communication network.
A network device, comprising:

a processing unit; and

a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the device to perform the method according to any of claims 1-12.
A terminal device, comprising:

a processing unit; and

a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the device to perform the method according to any of claims 13-26.
A transition network device, comprising

a processing unit; and

a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the device to perform the method according to any of claims 27-30.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to any of claims 1-12.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to any of claims 13-26.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to any of claims 27-30.