FIELD

[0001] Embodiments of the present disclosure generally relate to communication technologies, and more particularly, to a method and device for activation and deactivation of a wideband coverage enhancement (WCE) mode.

BACKGROUND

[0002] In MulteFire (MF) standardization 1.1, wideband coverage enhancement (WCE) is initially proposed as the new feature to support Internet of Things (IoT) services in unlicensed spectrum. Due to the deep fade caused by shadowing in IoT scenarios, coverage is an important performance metric for system design.

[0003] As a metric reflecting the supported maximum path loss, the maximum coupling loss (MCL) is introduced to describe the coverage performance. In MF standardization 1.0, the MCL of physical channels in DL is much lower than that of physical channels in UL because DL transmit power is limited in unlicensed spectrum and terminal devices are equipped with low-complexity receivers. Therefore, WCE in MF standardization 1.1 focuses on increasing the DL coverage performance to the level of UL coverage performance.

[0004] At present, the key technique for WCE is based on repetitions. Thus, the support of larger coverage will lower the spectrum efficiency. However, since the positions of terminal devices are distributed randomly, not all terminal devices based on MF standardization 1.1 suffer high shadowing fading and require large coverage. In order to increase the spectrum efficiency, terminal devices with small path loss should be served without additional repetitions.

SUMMARY

[0005] Generally the embodiments of the present disclosure propose a method and device for activation and deactivation of a WCE mode.

[0006] In a first aspect, the embodiments of the present disclosure provide a method implemented at a network device. The method comprises: receiving from a terminal device information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at the terminal device. The method further comprises: in response to determining to activate the WCE mode or the non-WCE mode at the terminal device based on the received information, transmitting an instruction for activating the WCE mode or the non-WCE mode to the terminal device.

[0007] In a second aspect, the embodiments of the present disclosure provide a method implemented at a terminal device. The method comprises: in response to being in a non-radio resource control (RRC)-idle state, transmitting to a network device information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at the terminal device, and in response to receiving an instruction for activating the WCE mode or the non-WCE mode, entering the WCE mode or the non-WCE mode for operation. The method further comprises: in response to being in an RRC-idle state, autonomously activating the WCE mode or the non-WCE mode.

[0008] In a third aspect, the embodiments of the present disclosure provide a method implemented at a network device. The method comprises: receiving, from a further network device that is a handover source of a terminal device, information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at the terminal device. The method further comprises: in response to determining to activate the WCE mode or the non-WCE mode at the terminal device based on the received information, transmitting an instruction for activating the WCE mode or the non-WCE mode.

[0009] In a fourth aspect, the embodiments of the present disclosure provide a network device. The network device comprises a controller and a memory coupled to the controller. The memory comprises instructions which, when executed by the controller, cause the network device to execute acts. The acts comprise: receiving from a terminal device information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at the terminal device; and in response to determining to activate the WCE mode or the non-WCE mode at the terminal device on the basis of the received information, transmitting an instruction for activating the WCE mode or the non-WCE mode to the terminal device.

[0010] In a fifth aspect, the embodiments of the present disclosure provide a terminal device. The terminal device comprises a controller and a memory coupled to the controller. The memory comprises instructions which, when executed by the controller, cause the terminal device to execute acts. The acts comprise: in response to being in a non-radio resource control (RRC)-idle state, transmitting to a network device information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at the terminal device, and in response to receiving an instruction for activating the WCE mode or the non-WCE mode, entering the WCE mode or the non-WCE mode for operation; and in response to being in an RRC-idle state, autonomously activating the WCE mode or the non-WCE mode. [0011] In a sixth aspect, the embodiments of the present disclosure provide a network device. The network device comprises a controller and a memory coupled to the controller. The memory comprises instructions which, when executed by the controller, cause the network device to execute acts. The acts comprise: receiving, from a further network device that is a handover source of a terminal device, information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at the terminal device; and in response to determining to activate the WCE mode or the non-WCE mode at the terminal device based on the received information, transmitting an instruction for activating the WCE mode or the non-WCE mode.

[0012] In a seventh aspect, the embodiments of the present disclosure provide a computer readable medium comprising computer executable instructions which, when executed on a device, cause the device to execute the method according to the first aspect.

[0013] In an eighth aspect, the embodiments of the present disclosure provide a computer readable medium comprising computer executable instructions which, when executed on a device, cause the device to execute the method according to the second aspect. [0014] In a ninth aspect, the embodiments of the present disclosure provide a computer readable medium comprising computer executable instructions which, when executed on a device, cause the device to execute the method according to the third aspect.

[0015] It should be appreciated that contents as described in the SUMMARY portion are not intended to limit key or important features of the embodiments of the present disclosure or used to limit the scope of the present disclosure. Other features of the present disclosure will become easier to understand from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other features, advantages and aspects of various embodiments of the present disclosure will become apparent from the following detailed illustration, when taken in conjunction with the accompanying drawings in which the same or similar reference numerals denote the same or similar elements, wherein: [0017] Fig. 1 shows an exemplary wireless communication network 100 in which the embodiments of the present disclosure are implemented;

[0018] Fig. 2 shows a flowchart of a method 200 according to the embodiments of the present disclosure; [0019] Fig. 3 shows a block diagram of an apparatus 300 according to the embodiments of the present disclosure;

[0020] Fig. 4 shows a block diagram of an apparatus 400 according to the embodiments of the present disclosure;

[0021] Fig. 5 shows a block diagram of an apparatus 500 according to the embodiments of the present disclosure; and

[0022] Fig. 6 shows a block diagram of a communication device which is applicable to implement some embodiments of the present disclosure.

[0023] It should be appreciated that contents as described in the SUMMARY portion are not intended to limit key or important features of the embodiments of the present disclosure or used to limit the scope of the present disclosure. Other features of the present disclosure will become easier to understand from the following description.

DETAILED DESCRIPTION OF EMBODIMENTS

[0024] Embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings, in which some embodiments of the present disclosure have been illustrated. However, the present disclosure can be implemented in various manners, and thus should not be construed to be limited to the embodiments disclosed herein. On the contrary, those embodiments are provided for the thorough and complete understanding of the present disclosure. It should be understood that the accompanying drawings and embodiments of the present disclosure are merely for the illustration purpose, rather than limiting the protection scope of the present disclosure.

[0025] The term "network device" used herein refers to other entity or node with specific functionality in a base station or communication network. The "base station (BS)" may represent a node B (NodeB or NB), an Evolved Node B (eNodeB or eNB), a remote radio unit (RRU), a radio-frequency head (RH), a remote radio head (RRH), a repeater, or a low power node such as a Picocell, a Femto cell and the like. In the context of the present disclosure, the terms "network device" and "base station" may be used interchangeably, and generally, the eNB is taken as an example of the network device, for the sake of discussion.

[0026] The term "terminal device" or "user equipment" (UE) used herein refers to any terminal device that can perform wireless communication with the network device or one another. As an example, the terminal device may comprise a mobile terminal (MT), a subscriber station (SS), a portable subscriber station (PSS), a mobile station (MS) or an access terminal (AT), and the above on-board devices. In the context of the present disclosure, the terms "terminal device" and "user equipment" may be used interchangeably for the sake of discussion.

[0027] The term "comprise" and its variants used herein are to be read as open terms that mean "include, but is not limited to". The term "based on" is to be read as "based at least in part on". The term "one embodiment" is to be read as "at least one embodiment"; the term "another embodiment" is to be read as "at least one other embodiment". Definitions of other terms will be presented in description below.

[0028] Fig. 1 shows an exemplary wireless communication network 100 in which the embodiments of the present disclosure may be implemented. The wireless communication network 100 comprises a network device 110 and a terminal device 120.

[0029] Communication between the network device 110 and the terminal device 120 may be implemented according to any appropriate communication protocol, including without limitation to, the first generation (1G), the second generation (2G), the third generation (3G), the fourth generation (4G), the fifth generation (5G) and other cellular communication protocol, wireless local area network communication protocols such as Institute of Electrical and Electronics Engineers (IEEE) 802.11, and/or any other protocols that are currently known or to be developed later. Furthermore, the communication utilizes any appropriate wireless communication technology, including without limitation to, code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), frequency division duplexing (FDD), time division duplexing (TDD), multiple input multiple output (MIMO), orthogonal frequency division multiplexing (OFDM), and/or any other technology that is currently known or to be developed in future. It is noteworthy although an LTE system is used as an example for description in the embodiments of the present disclosure, this is merely exemplary, and the technical solution of the present application is completely applicable to other appropriate system that is existing or to be developed in future. [0030] It should be appreciated the number of network device and the number of terminal device as shown in Fig. 1 are merely for the illustration purpose, without suggesting any limitation. The wireless communication network 100 may comprise any appropriate type and number of network devices each of which may provide any appropriate number of cells, and further the wireless communication system 100 may comprise any appropriate number of terminal devices.

[0031] In LTE standards, there have been proposed IoT support technologies including enhanced Machine-Type Communication (eMTC). For eMTC, the basic idea for achieving coverage enhancement is to use repetitions. For example, multiple repetitions (or copies) of the same packet are repetitively transmitted in multiple sub-frames. In the present disclosure, the term "repetition" refers to a copy of a signal, for example, including complete repetition, using different channel coding, etc. By transmitting multiple repetitions of a signal at multiple transmitting timing, transmit power of the signal may be increased, thereby increasing the probability that the receiver correctly detects the signal and further enhancing coverage.

[0032] In eMTC, the number of repetitions is a variable that is determined by the network device. The network device never explicitly indicates "no repetitions" to terminal devices, i.e., deactivating the repetition mode of terminal devices. In other words, the repetition mode will come along with eMTC all the while. Therefore, eMTC does not consider activation and deactivation of the repetition mode, and the eMTC mechanism is not suitable for WCE in MF standardization 1.1.

[0033] In addition, since the uplink channel is not enhanced for MF standardization 1.1, the network device operating based on MF standardization 1.1 cannot activate or deactivate the WCE mode by detecting the coverage enhancement level based on the number of repetitions for Physical Random Access Channel, like eMTC.

[0034] To at least partially solve the foregoing and other potential drawbacks and problems in conventional solutions, the embodiments of the present disclosure propose the following: where the network device can obtain information on activation of a WCE mode or a non-WCE mode from the terminal device, the network device determines to activate or deactivate the WCE mode at the terminal device according to the information obtained from the terminal device; where the network device cannot obtain the information from the terminal device, the terminal device autonomously activates the WCE mode or the non-WCE mode at the terminal device. Thereby, it may be avoided that the WCE mode at the terminal device is activated unnecessarily and thus the spectrum efficiency may be increased.

[0035] In the present disclosure, "to activate a WCE mode at the terminal device" and "to deactivate a non-WCE mode at the terminal device" may be used interchangeably, and "to activate a non-WCE mode at the terminal device" and "to deactivate a WCE mode at the terminal device" may be used interchangeably. With reference to Fig. 2, a detailed description is presented below to a method for activating the WCE mode or the non-WCE mode at a terminal device according to the present disclosure.

[0036] Fig. 2 shows a flowchart of a method 200 for activating WCE mode or non-WCE mode at a terminal device according to an embodiment of the present disclosure. Acts involved in the method 200 will be described in conjunction with Fig. 1. For the sake of discussion, the method 200 will be described in conjunction with the network device 110 and the terminal device 120 as shown in Fig. 1. In Fig. 2, for example, each act on the left is executed by the terminal device 120, while each act on the right is executed by the network device 110. It should be understood the method 200 may further comprise additional acts that are not shown and/or omit acts that have been shown, and the scope of the present disclosure is not limited in this regard.

[0037] As shown in Fig. 2, at block 201, the terminal device 120 determines whether it is in a Radio Resource Control (RRC)-idle state. If the terminal device 120 determines it is not in the RRC-idle state, that is, the terminal device 120 is in a non-RRC-idle state, the terminal device 120 transmits at block 202 to the network device 110 information on activation of a WCE mode or a non-WCE mode at the terminal device 120. Accordingly, at block 203, the network device 110 receives from the terminal device 120 the information on activation of the WCE mode or non-WCE mode at the terminal device 120. [0038] In some embodiments, the information on activation of the WCE mode or non-WCE mode at the terminal device 120 comprises at least one of: acknowledgment information (e.g. ACK or NACK) associated with a downlink transmission, Channel State Information (CSI) feedback between the terminal device 120 and the network device 110, and assistant information associated with activation of the WCE mode or non-WCE mode at the terminal device 120.

[0039] In some embodiments, the assistant information on activation of the WCE mode or non-WCE mode at the terminal device 120 comprises at least one of: a first indication indicating the terminal device 120 expects for the WCE mode, a second indication indicating the terminal device 120 expects for the non-WCE mode, a Reference Signal Received Power (RSRP), a Reference Signal Received Quality (RSRQ) as well as a request flag. The request flag indicates the urgency of the terminal device 120 expecting for the WCE mode. [0040] In an embodiment where the assistant information comprises a first indication indicating the terminal device 120 expects for the WCE mode, a second indication indicating the terminal device 120 expects for the non-WCE mode, the RSRP and the RSRQ, the assistant information may have a structure as below:

WCERequest::= SEQUENCE {

suggestedMode ENUMERATED {WCE, Non-WCE}

RSRQ INTEGER (-34.. -3)

RSRP INTEGER (-70.. -22)

}

[0041] In the foregoing exemplary structure, suggestedMode represents the first indication indicating the terminal device 120 expects for the WCE mode and the second indication indicating the terminal device 120 expects for the non-WCE mode.

[0042] In an embodiment where the assistant information at least comprises a first indication indicating the terminal device 120 expects for the WCE mode, a second indication indicating the terminal device 120 expects for the non-WCE mode, as well as a request flag indicating the urgency of the terminal device 120 expects for the WCE mode, the assistant information may have a structure as below:

WCERequest::= SEQUENCE {

suggestedMode ENUMERATED {WCE, Non-WCE}

requestFlag ENUMERATED {True, False}

}

[0043] In the foregoing exemplary structure, suggestedMode represents the first indication indicating the terminal device 120 expects for the WCE mode the second indication indicating the terminal device 120 expects for the non-WCE mode, and requestFlag represents the request flag indicating urgency of the terminal device 120 expecting for the WCE mode. When requestFlag is set to True, it indicates high urgency of the terminal device 120 expecting for the WCE mode; when requestFlag is set to False, it indicates low urgency of the terminal device 120 expecting for the WCE mode.

[0044] In some embodiments, the terminal device 120 transmits the assistant information to the network device 110 via at least one of: high layer signaling (e.g. RRC signaling), a radio resource allocated for an uplink scheduling request, a random access request, a physical random access channel resource, and an uplink transmission in response to a random access response.

[0045] At block 204, the network device 110 determines, based on the information received from the terminal device 120, whether to activate the WCE mode or non-WCE mode at the terminal device 120. [0046] For example, when the network device 110 determines, based on the CSI feedback received from the terminal device 120, channel conditions between the network device 110 and the terminal device 120 are rather poor, the network device 110 may determine to activate the WCE mode at the terminal device 120. When the network device 110 determines, based on the CSI feedback, the channel conditions between the network device 110 and the terminal device 120 are good and the terminal device 120 is currently in the WCE mode, the network device 110 may determine to activate the non-WCE mode at the terminal device 120. When the network device 110 determines, based on the CSI feedback, the channel conditions between the network device 110 and the terminal device 120 are good and the terminal device 120 is currently in the non-WCE mode, the network device 110 may determine not to change a current operating mode of the terminal device 120, i.e. neither activate the WCE mode at the terminal device 120 nor activate the non-WCE mode at the terminal device 120. It should be understood that the network device 110 may determine whether to activate the WCE mode or non-WCE mode at the terminal device 120 according to any appropriate criterion, and the scope of the present disclosure is not limited in this regard. [0047] If the network device 110 determines at block 204 to activate the WCE mode or the non-WCE mode at the terminal device 120, the method 200 proceeds to block 205 at which the network device 110 transmits an instruction for activating the WCE mode or non-WCE mode to the terminal device 120. Accordingly, the terminal device 120 receives at block 206 the instruction for activating the WCE mode or the non-WCE mode from the network device 110 and further enters the WCE mode or non-WCE mode for operation.

[0048] In an embodiment where the terminal device 120 enters the WCE mode for operation, the terminal device 120 will monitor signals designed for the WCE mode (abbreviated as "WCE signals") and ignore signals designed for the non-WCE mode (abbreviated as "non-WCE signals"). Examples of the signals designed for the WCE mode may include, but not limited to, coverage enhanced synchronization signals, coverage enhanced broadcast signals, coverage enhanced control signals and coverage enhanced data signals. In addition, the terminal device 120 needs to obtain a coverage enhancement level (e.g. the number of repetitions) before receiving or decoding the WCE signals.

[0049] For example, the coverage enhancement level may be a predefined value. For another example, the terminal device 120 may obtain the coverage enhancement level from the network device 110 via RRC signaling or a dynamical indicator in downlink control information (DCI). For a further example, the terminal device 120 may obtain the coverage enhancement level by blind decoding the downlink signal. It should be understood that no coverage enhancement (e.g. no repetitions) may be an option of the coverage enhancement level. After obtaining the coverage enhancement level, the terminal device 120 may receive or decode the WCE signals based on the coverage enhancement level. [0050] In an embodiment where the terminal device 120 enters the non-WCE mode for operation, the terminal device 120 will monitor the non-WCE signals and ignore the WCE signals. When no terminal devices operate in the WCE mode, the network device 110 may pause the transmission of the WCE signals to increase the spectrum efficiency.

[0051] In some embodiments, the terminal device 120 may operate in both WCE mode and non-WCE mode simultaneously, i.e., the terminal device 120 will monitor both the WCE and non-WCE signals simultaneously. In such embodiments, the CSI measurement based on WCE reference signals should be aligned with the CSI measurement based on non-WCE reference signals.

[0052] Still with reference to Fig. 2, if the network device 110 determines at block 204 not to activate the WCE mode or the non-WCE mode at the terminal device 120, the method 200 proceeds to block 207 at which the network device 110 executes any appropriate operation. In this case, the terminal device 120 will maintain its current operating mode (WCE mode or non-WCE mode). If the terminal device 120 still expects to change its current operating mode, then the terminal device 120 may re-transmit to the network device 110 the information on activation of the WCE mode or the non-WCE mode at the terminal device 120.

[0053] In some embodiments, transmitting the instruction for activating the WCE mode or the non-WCE mode to the terminal device 120 comprises: transmitting first control information for activating the WCE mode to the terminal device 120, or transmitting second control information for activating the non-WCE mode to the terminal device 120.

[0054] If the assistant information transmitted by the terminal device 120 to the network device 110 at least comprises the request flag (e.g. requestFlag) indicating urgency of the terminal device 120 expecting for the WCE mode and the request flag indicates high urgency of the terminal device 120 expecting for the WCE mode, it means the terminal device 120 in the non-WCE mode cannot receive reference signals of the non-WCE mode and urgently expects for the WCE mode for operation. In such an embodiment, the network device 110 preferentially transmits first control information for activating the WCE mode to the terminal device 120 in the WCE mode, so as to ensure that the terminal device 120 can receive the first control information to enter the WCE mode for operation. Accordingly, the terminal device 120 receives the first control information in the WCE mode, i.e., monitors the first control information designed for the WCE mode.

[0055] In some embodiments, the network device 110 transmits the first control information or the second control information to the terminal device 120 via at least one of: DCI, high layer signaling, and a channel resource for physical random access response.

[0056] It will be appreciated that examples of the non-RRC-idle state may include, but not limited to, RRC-connected maintenance state, RRC connection establishment state, and RRC connection reconfiguration state. The method according to the present disclosure will be described in conjunction with these examples of the non-RRC-idle state.

RRC-Connected Maintenance State

[0057] In RRC-connected maintenance state, the network device 110 receives CSI feedback and acknowledgment information (e.g. ACK or NACK) associated with a downlink transmission from the terminal device 120. [0058] The terminal device 120 receives the reference signals from the network device 110 and measures them. Examples of the reference signals may include, but not limited to, (MF-) primary synchronization signals ((MF-)PSS, (MF-) secondary synchronization signals ((MF-)SSS), physical broadcast channel (PBCH) signals, cell-specific reference signals (CRS), and demodulation reference signals (DRS). [0059] If the terminal device 120 expects for the WCE mode or the non-WCE mode, then the terminal device 120 may transmit to the network device 110 assistant information associated with activation of the WCE mode or the non-WCE mode at the terminal device 120. The assistant information may include, but not limited to, at least one of: a first indication indicating the terminal device 120 expects for the WCE mode, a second indication indicating the terminal device 120 expects for the non-WCE mode, RSRP, RSRQ, and a request flag indicating urgency of the terminal device 120 expecting for the WCE mode. [0060] After transmitting the assistant information, the terminal device 120 may monitor, in a current operating mode (WCE or non-WCE), an instruction for activating the WCE mode or the non-WCE mode. After receiving the instruction, the terminal device 120 enters the activated mode for operation.

RRC Connection Establishment State

[0061] In the RRC connection establishment state, the terminal device 120 may determine, according to reference signals received from the network device 110, whether the WCE mode or the non-WCE mode is expected to be activated. Specifically, the terminal device 120 may try to receive the reference signals designed for the WCE mode and the non-WCE mode respectively and then choose the better one. For example, if the terminal device 120 cannot correctly receive the reference signal designed for the non-WCE mode but only can receive the reference signal designed for the WCE mode, the terminal device 120 may determine to activate the WCE mode.

[0062] The terminal device 120 may implicitly or explicitly transmit to the network device 110 a first indication of expecting for the WCE mode or a second indication of expecting for the non-WCE mode.

[0063] In some embodiments, the first indication of expecting for the WCE mode or the second indication of expecting for the non-WCE mode may be carried by a random access request on a short physical random access channel (sPRACH) or an enhanced physical random access channel (ePRACH). As one example, the first indication or the second indication may be carried by the preamble based on ZC sequence. For instance, if the terminal device 120 chooses the roots 1-10 of ZC sequences, it indicates the terminal device 120 expects for the non-WCE mode. If the terminal device 120 chooses the roots 11-20 of ZC sequences, it indicates the terminal device 120 expects for the non-WCE mode.

[0064] In some embodiments, the first indication of expecting for the WCE mode or the second indication of expecting for the non-WCE mode may be carried by the resource allocation of a physical random access channel (e.g. sPRACH or ePRACH). For instance, if the terminal device 120 chooses subframes # 2-4, it indicates the terminal device 120 expects for the non-WCE mode. If the terminal device 120 chooses subframes # 7-9, it indicates the terminal device 120 expects for the WCE mode.

[0065] In other embodiments, the first indication of expecting for the WCE mode or the second indication of expecting for the non-WCE mode may be carried by an uplink transmission in response to a random access response. For example, the network device 110 transmits "Random Access Response Grant" of the same resource allocation in both WCE mode and non-WCE mode. After receiving the "Random Access Response Grant" in the expected mode, the terminal device 120 may implicitly or explicitly transmit the first indication of expecting for the WCE mode or the second indication of expecting for the non-WCE mode in message 3 (Msg3) on the physical uplink shared channel (PUSCH). For example, in the explicit manner, the terminal device 120 may transmit the first indication or the second indication as information of message 3. In the implicit manner, the terminal device 120 may scramble message 3 using the first indication or the second indication.

[0066] After receiving the first indication or the second indication from the terminal device 120, the network device 110 may determine, based on the first indication or the second indication, whether to activate the operating mode expected by the terminal device 120, i.e. activate the WCE mode or the non-WCE mode. If the network device 110 determines to activate the WCE mode or the non-WCE mode, the network device 110 may implicitly or explicitly transmit an instruction for activating the WCE mode or the non-WCE mode to the terminal device 120.

[0067] For example, the network device 110 may explicitly transmit the instruction for activating the mode (WCE or non-WCE mode) expected by the terminal device 120 via DCI or RRC signaling in the mode expected by the terminal device 120, and the terminal device 120 monitors DCI or RRC signaling in the expected mode. [0068] For another example, the network device 110 may transmit "Random Access Response Grant" to the terminal device 120 in the WCE mode or the non-WCE mode which is determined to be activated. The terminal device 120 monitors DCI or RRC signaling in both WCE mode and non-WCE mode and obtains the actual operating mode according to the transmission of "Random Access Response Grant." RRC Connection Reconfiguration State

[0069] In the RRC connection reconfiguration state, for example, the terminal device 120 may transmit via RRC signaling the information on activation of the WCE mode or the non-WCE mode at the terminal device 120 to the network device 110 that is a handover source. The information may comprise, for example, CSI feedback, and a first indication of expecting for the WCE mode or a second indication of expecting for the non-WCE mode. Then, the network device 110 that is the handover source may forward the information received from the terminal device 120 to a further network device that is a handover target via S1/X2 interface by using a structure as below:

WCEModeInterCell::= SEQUENCE {

TargetPhysCellld INTEGER (0..503)

suggestedMode ENUMERATED {WCE, Non-WCE}

RSRQ INTEGER (-34..-3)

RSRP INTEGER (-70..-22)

}

[0070] In the foregoing structure, "TargetPhysCellld" represents the identification of a target cell. Accordingly, the further network device that is the handover target receives the information on activation of the WCE mode or the non-WCE mode from the network device 110 that is the handover source.

[0071] Subsequently, the further network device that is the handover target determines whether to activate the WCE mode or the non-WCE mode at the terminal device 120 based on the received information. If the further network device that is the handover target determines to activate the WCE mode or the non-WCE mode at the terminal device 120, then the further network device may transmit an instruction for activating the WCE mode or the non-WCE mode at the terminal device 120 to the network device 110 via S1/X2 interface. Further the network device 110 forwards the instruction to the terminal device 120. Alternatively, the further network device that is the handover target may directly transmit the instruction to the terminal device 120.

[0072] In response to receiving the instruction, when the terminal device 120 receives the downlink transmission from the further network device that is the handover target, the terminal device 120 may operate in the activated mode. [0073] Return to Fig. 2, if the terminal device 120 determines at block 201 that it is in RRC-idle state, then the method 200 proceeds to block 208 at which the terminal device 120 autonomously activates the WCE mode or the non-WCE mode.

[0074] In some embodiments, the terminal device 120 may determine to activate the WCE mode or the non-WCE mode according to reference signals received from the network device 110. The network device 110 may transmit paging information to the terminal device 120 in both WCE mode and non-WCE mode simultaneously. Examples of the paging information may include, but not limited to, broadcast information and a trigger command causing the terminal device 120 to handover from the RRC-idle state to the RRC-connected state. The terminal device 120 may receive the paging information in any of WCE mode and non-WCE mode. If the terminal device 120 receives the paging information including the trigger command, then the terminal device 120 starts to resume the RRC connection with the network device 110.

[0075] In some embodiments, the terminal device 120 may determine to activate the WCE mode or the non-WCE mode according to reference signals received from the network device 110. For example, the terminal device 120 may determine to activate the WCE mode. In such an example, the network device 110 may first transmit the paging information including the trigger command to the terminal device 120 in the non-WCE mode. At this point, the terminal device 120 cannot receive the paging information in the WCE mode and further will not transmit a random access request to the network device 110 for resuming the RRC connection with the network device 110. Since the network device 110 receives no random access requests from the terminal device 120, the network device 110 will re-transmit the paging information to the terminal device 120 in the WCE mode. In this case, the terminal device 120 will receive the paging information in the WCE mode and further transmit a random access request to the network device 110 for resuming the RRC connection with the network device 110.

[0076] In some embodiments, the terminal device 120 may maintain the WCE mode or the non-WCE mode in the RRC-connected state after which the terminal device 120 enters the RRC-idle state. In such embodiments, the network device 110 transmits the paging information to the terminal device 120 in the operating mode at the time of RRC connection before the terminal device 120 enters the RRC-idle state. If the terminal device 120 receives the paging information including the trigger command, then the terminal device 120 transmits a random access request to the network device 110 in order to resume the RRC connection with the network device 110. If the terminal device 120 in the non-WCE mode cannot receive any reference signal for the non-WCE mode, then the terminal device 120 reestablishes a connection with the network device 110.

[0077] In some embodiments, in the RRC-idle state, the terminal device 120 may operate in the WCE mode as default. In other words, if the terminal device 120 operates in the non-WCE mode in the RRC-connected state after which the terminal device 120 enters the RRC-idle state, then the terminal device 120 will activate WCE mode after entering the RRC-idle state. If the terminal device 120 operates in the WCE mode in the RRC-connected state after which the terminal device 120 enters the RRC-idle state, then the terminal device maintains the WCE mode after entering RRC-idle state. In such embodiments, the network device 110 transmits the paging information to the terminal device 120 in the WCE mode, and the terminal device 120 monitors the paging information in the WCE mode. If the network device 110 pauses the transmission of WCE signals, then the terminal device 120 cannot receive reference signals designed for the WCE mode. In this case, if the terminal device 120 can receive reference signals designed for the non-WCE mode, then the terminal device 120 activates the non-WCE mode and further operates in the non-WCE mode. If the terminal device 120 cannot receive reference signals designed for the non-WCE mode, then the terminal device 120 reestablishes a connection with the network device 110.

[0078] While the communication method according to the embodiments of the present disclosure has been described in detail with reference to Fig. 2, description is presented below to apparatuses according to the embodiments of the present disclosure with reference to Figs. 3 and 4.

[0079] Fig. 3 shows a block diagram of an apparatus 300 according to some embodiments of the present disclosure. It may be understood that the apparatus 300 may be implemented at the network device 110 side as shown in Fig. 1. As depicted in Fig. 3, the apparatus 300 (e.g. the network device 110) comprises a first information receiving unit 310 and a first activating unit 320. The first information receiving unit 310 is configured to receive from a terminal device information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at the terminal device. The first activating unit 320 is configured to, in response to determining to activate the WCE mode or the non-WCE mode at the terminal device based on the received information, transmit an instruction for activating the WCE mode or the non-WCE mode to the terminal device.

[0080] In some embodiments, receiving the information on activation of the WCE mode or the non-WCE mode comprises receiving from the terminal device at least one of: acknowledgment information associated with a downlink transmission, channel state information (CSI) between the terminal device and the network device, and assistant information on activation of the WCE mode or the non-WCE mode at the terminal device.

[0081] In some embodiments, receiving the assistant information comprises receiving at least one of: a first indication indicating that the terminal device expects for the WCE mode, a second indication indicating that the terminal device expects for the non-WCE mode, a reference signal received power (RSRP), a reference signal received quality (RSRQ), and a request flag indicating urgency of the terminal device expecting for the WCE mode.

[0082] In some embodiment, receiving the assistant information comprises receiving the assistant information via at least one of: high layer signaling, a radio resource allocated for an uplink scheduling request, a random access request, a physical random access channel resource, and an uplink transmission in response to a random access response.

[0083] In some embodiments, transmitting an instruction for activating the WCE mode or the non-WCE mode to the terminal device comprises: transmitting first control information for activating the WCE mode to the terminal device; or transmitting second control information for activating the non-WCE mode to the terminal device.

[0084] In some embodiments, transmitting the first control information to the terminal device comprises: in response to receiving the request flag, transmitting in the WCE mode the first control information to the terminal device. [0085] In some embodiments, transmitting the first control information or the second control information to the terminal device comprises: transmitting the first control information or the second control information via at least one of: downlink control information (DCI), high layer signaling, and a channel resource for a physical random access response.

[0086] In some embodiments, the apparatus 300 further comprises a forwarding unit. The forwarding unit is configured to forward the received information to a further network device that is a handover target of the terminal device.

[0087] In some embodiments, transmitting an instruction for activating the WCE mode or the non-WCE mode to the terminal device comprises: in response to receiving the instruction from the further network device, transmitting the instruction to the terminal device. [0088] Fig. 4 shows a block diagram of an apparatus 400 according to some embodiments of the present disclosure. It may be understood that the apparatus 400 may be implemented at the terminal device 120 side shown in Fig. 1. As depicted in Fig. 4, the apparatus 400 (e.g. the terminal device 120) comprises an information transmitting unit 410, an instruction receiving unit 420 and an autonomous activating unit 430. The information transmitting unit 410 is configured to, in response to being in a non-radio resource control (RRC)-idle state, transmit to a network device information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at a terminal device. The instruction receiving unit 420 is configured to, in response to receiving an instruction for activating the WCE mode or the non-WCE mode, enter the WCE mode or the non-WCE mode for operation. The autonomous activating unit 430 is configured to, in response to being in an RRC-idle state, autonomously activate the WCE mode or the non-WCE mode.

[0089] In some embodiments, transmitting the information on activation of the WCE mode or the non-WCE mode comprises transmitting at least one of: acknowledgment information associated with a downlink transmission, channel state information (CSI) between the terminal device and the network device, and assistant information on activation of the WCE mode or the non-WCE mode at the terminal device.

[0090] In some embodiments, transmitting the assistant information comprises transmitting at least one of: a first indication indicating that the terminal device expects for the WCE mode, a second indication indicating that the terminal device expects for the non-WCE mode, a reference signal received power (RSRP), a reference signal received quality (RSRQ), and a request flag indicating urgency of the terminal device expecting for the WCE mode.

[0091] In some embodiments, transmitting the assistant information comprises transmitting the assistant information via at least one of: high layer signaling, a radio resource allocated for an uplink scheduling request, a random access request, a physical random access channel resource, and an uplink transmission in response to a random access response. [0092] In some embodiments, entering the WCE mode or the non-WCE mode for operation comprises: in response to receiving first control information for activating the WCE mode from the network device, entering the WCE mode for operation; and in response to receiving second control information for activating the non-WCE mode from the network device, entering the non-WCE mode for operation. [0093] In some embodiments, entering the WCE mode or the non-WCE mode for operation comprises: in response to transmitting the request flag to the network device, receiving in the WCE mode the first control information from the network device. [0094] In some embodiments, receiving the first control information or the second control information comprises receiving the first control information or the second control information via at least one of: downlink control information (DCI), high layer signaling, and a channel resource of a physical random access response. [0095] In some embodiments, entering the WCE mode or the non-WCE mode for operation comprises: in response to receiving the instruction for activating the WCE mode or the non-WCE mode from a further network device that is a handover target, entering the WCE mode or the non-WCE mode for operation.

[0096] In some embodiments, autonomously activating the WCE mode or the non-WCE mode at the terminal device comprises one of: autonomously activating the WCE mode or the non-WCE mode according to a reference signal received from the network device; maintaining the WCE mode or the non-WCE mode in an RRC-connected state after which the terminal device enters the RRC-idle state; and activating the WCE mode as default.

[0097] Fig. 5 shows a block diagram of an apparatus 500 according to some embodiments of the present disclosure. It may be understood that the apparatus 500 may be implemented at the network device (not shown in Fig. 1) side that is a handover target of the terminal device 120 in Fig. 1. As depicted in Fig. 5, the apparatus 500 comprises a second information receiving unit 510 and a second activating unit 520. The second information receiving unit 510 is configured to receive information on activation of a wideband coverage enhancement (WCE) mode or a non-WCE mode at a terminal device from a further network device that is a handover source of the terminal device. The second activating unit 520 is configured to, in response to determining to activate the WCE mode or the non-WCE mode at the terminal device based on the received information, transmit an instruction for activating the WCE mode or the non-WCE mode. [0098] In some embodiments, transmitting the instruction for activating the WCE mode or the non-WCE mode comprises: transmitting the instruction for activating the WCE mode or the non-WCE mode to the terminal device.

[0099] In some embodiments, transmitting the instruction for activating the WCE mode or the non-WCE mode comprises: transmitting the instruction for activating the WCE mode the non-WCE mode to the terminal device via the further network device.

[00100] It will be appreciated each unit of the apparatuses 300, 400 and 500 corresponds to each step of the method 200 described with reference to Fig. 2. Therefore, operations and features described above with reference to Fig. 2 are also applicable to the apparatuses 300, 400, 500 as well as units included in them, and meanwhile have the same effect, details of which are ignored here.

[00101] It is to be noted that the units included in the apparatuses 300, 400 and 500 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 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), etc.

[00102] The units shown in Figs. 3 to 5 may be implemented, partially or entirely, as hardware modules, software modules, firmware modules or any combination thereof. In particular, in some embodiments, the flows, methods or processes described above may be implemented by hardware in a base station or terminal device. For example, the base station or terminal device may implement the method 200 by means of its transmitter, receiver, transceiver and/or processor. [00103] Fig. 6 shows a block diagram of a device 600 which is applicable to implement the embodiments of the present disclosure. The device 600 may be used for implementing a network device or a terminal device.

[00104] As depicted, the device 600 comprises a controller 610. The controller 610 controls operations and functions of the device 600. For example, in some embodiments, the controller 610 may execute various operations by means of instructions 630 stored in a memory 620 coupled to the controller 610. The memory 620 may be of any appropriate type that is applicable to a local technical environment, and may be implemented using any appropriate data storage techniques, including without limitation to, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems. Though only one memory unit is shown in Fig. 6, there may be a plurality of physically different memory units in the device 600.

[00105] The controller 610 may be of any appropriate type that is applicable to a local technical environment, and may include without limitation to, a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), as well as one or more processors in a processor based multi-core processor architecture. The device 600 may also comprise multiple controllers 610. The controller 610 is coupled to a transceiver 640 that may effect information receiving and transmitting by means of one or more antennas 650 and/or other component. Note in the context of the present disclosure the transceiver 640 may be a device capable of effecting both data sending and receiving or may be a device capable of effecting data sending or transmitting only.

[00106] When the device 600 acts as a network device, the controller 610 and the transceiver 640 may operate in cooperation to implement operations at the network device 110 in the method 200 described with reference to Fig. 2. When the device 600 acts as a terminal device, the controller 610 and the transceiver 640 may operate in cooperation to implement operations at the terminal device 120 in the method 200 described with reference to Fig. 2. For example, in some embodiments, all actions relating to data/information receiving/transmitting as described above may be performed by the transceiver 640, and other actions may be performed by the controller 610. All features described with reference to Figs. 1 to 5 are applicable to the device 600, details of which are ignored here.

[00107] 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.

[00108] For example, embodiments of the present disclosure can be described in the general context of machine-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor. 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.

[00109] 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.

[00110] In the context of this disclosure, a machine readable medium 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 is not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of 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.

[00111] 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.

[00112] Although the subject matter has been described in a language that is specific to structural features and/or method actions, it is to be understood the subject matter defined in the appended claims is not limited to the specific features or actions described above. On the contrary, the above-described specific features and actions are disclosed as an example of implementing the claims.