CN108347737B

CN108347737B - Communication method and apparatus

Info

Publication number: CN108347737B
Application number: CN201710061250.XA
Authority: CN
Inventors: 刘海静; 王河
Original assignee: Nokia Shanghai Bell Co Ltd
Current assignee: Nokia Shanghai Bell Co Ltd
Priority date: 2017-01-25
Filing date: 2017-01-25
Publication date: 2021-08-06
Anticipated expiration: 2037-01-25
Also published as: CN108347737A

Abstract

Embodiments of the present disclosure relate to communication methods and devices. For example, in response to searching for a candidate relay device, measuring an edge link discovery reference signal received power (SD-RSRP) of the candidate relay device with one measurement period; selecting a relay device from the candidate relay devices to pair based on the measurement of the SD-RSRP; determining whether the SD-RSRP of the selected relay device meets a period extension condition; and extending a measurement period for measuring the SD-RSRPs of the selected relay device and other relay devices among the candidate relay devices in response to the SD-RSRP of the selected relay device satisfying a period extension condition.

Description

Communication method and apparatus

Technical Field

Embodiments of the present disclosure relate generally to communication technology, and more particularly, to communication methods and apparatuses.

Background

Low power consumption is seen as a fundamental requirement for internet of things (loT) devices, particularly wearable devices. In the RAN #71 conference, the SI entitled "further enhanced LTE device to device, for loT and wearable terminal device to network relay" is passed. The main goal of this research is to address power efficiency for evolved remote devices (e.g., wearable devices).

For selection and reselection of legacy proximity services (ProSe) relay devices, the remote device needs to search for candidate relay devices at each discovery period and measure the side link discovery reference signal received power (SD-RSRP) at each measurement period. However, in some cases, the search and SD-RSRP measurement operations for candidate relay devices in the related art are excessive, which causes a waste of power consumption of the remote device.

Disclosure of Invention

In general, embodiments of the present disclosure propose communication methods implemented at a terminal device and corresponding terminal devices.

In a first aspect, embodiments of the present disclosure provide a method of communication implemented at a terminal device. The method comprises the following steps: in response to searching for a candidate relay device, measuring an edge link discovery reference signal received power (SD-RSRP) of the candidate relay device with one measurement period; selecting a relay device from the candidate relay devices to pair based on the measurement of the SD-RSRP; determining whether the SD-RSRP of the selected relay device meets a period extension condition; and extending the measurement period for measuring the SD-RSRPs of the selected relay device and other relay devices of the candidate relay devices in response to the SD-RSRP of the selected relay device satisfying a period extension condition.

In a second aspect, embodiments of the present disclosure provide a terminal device. The terminal device includes: a transceiver; and a controller coupled to the transceiver and configured by the controller to: in response to searching for a candidate relay device, measuring an edge link discovery reference signal received power (SD-RSRP) of the candidate relay device with one measurement period; selecting a relay device from the candidate relay devices to pair based on the measurement of the SD-RSRP; determining whether the SD-RSRP of the selected relay device meets a period extension condition; and extending the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices of the candidate relay devices in response to the SD-RSRP of the selected relay device satisfying a period extension condition.

As will be understood from the following description, according to the paired movement characteristics of the terminal device and the relay device, the search and measurement period of the candidate relay device can be extended to reduce the search and measurement operations for the candidate relay device SD-RSRP to save the power consumption of the terminal device according to the embodiments of the present disclosure.

It should be understood that the statements herein reciting aspects are not intended to limit the critical or essential features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become apparent from the following description.

Drawings

The above and other features, advantages and aspects of various embodiments of the present disclosure will become more apparent by referring to the following detailed description when taken in conjunction with the accompanying drawings. In the drawings, like or similar reference characters designate like or similar elements, and wherein:

FIG. 1 illustrates an example communication network in which embodiments of the present disclosure may be implemented;

fig. 2 illustrates a flow diagram of an example communication method in accordance with certain embodiments of the present disclosure;

FIG. 3 illustrates a schematic diagram of cycle extension according to certain embodiments of the present disclosure;

fig. 4 illustrates a flow diagram of an example communication method 400 according to other embodiments of the present disclosure;

FIG. 5 illustrates a schematic diagram of a cycle extension according to the example communication method 400 of FIG. 4 according to other embodiments of the present disclosure;

FIG. 6 illustrates a block diagram of an apparatus according to certain embodiments of the present disclosure; and

fig. 7 illustrates a block diagram of an apparatus in accordance with certain embodiments of the present disclosure.

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

Detailed Description

Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the present disclosure are shown in the drawings, it is to be understood that the present disclosure may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, but rather are provided for a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the disclosure are for illustration purposes only and are not intended to limit the scope of the disclosure.

The term "network device" as used herein refers to a base station or other entity or node having a particular function in a communication network. A "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 Head (RH), a Remote Radio Head (RRH), a relay, or a low power node such as a pico base station, a femto base station, or the like. In the context of the present disclosure, the terms "network device" and "base station" may be used interchangeably for purposes of discussion convenience, and may primarily be referred to as an eNB as an example of a network device.

The term "terminal equipment" or "user equipment" (UE) as used herein refers to any terminal equipment capable of wireless communication with a base station or with each other. As an example, the terminal device may include 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-described devices in a vehicle. In the context of the present disclosure, the terms "terminal device" and "user equipment" may be used interchangeably for purposes of discussion convenience.

The terms "include" and variations thereof as used herein are inclusive and open-ended, i.e., "including but not limited to. The term "based on" is "based, at least in part, on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment". Relevant definitions for other terms will be given in the following description.

As described above, in the current 3GPP standardization work, research on power efficiency of remote devices has been proposed. To select and reselect a relay device for proximity services (ProSe), a remote device needs to search for candidate relay devices every discovery period and measure SD-RSRP every measurement period. In a conventional LTE system, for a remote device configured by an upper layer for relay operation, when RSRP measurement of a serving cell or PCell is less than a threshold, the remote device searches for a candidate relay device in each discovery period for selection or reselection. If the remote device has the selected side link relay device, the remote device measures the SD-RSRP of the selected relay device once every four discovery periods and evaluates whether it meets the relay selection criteria (defined at 3GPP TS 36.331V14.0.0 (2016-09)). Remote device per use T for intra-frequency relay device_{measure,ProSe_Relay_Intra}SD-RSRP of the relay device of the measurement candidate (detected and measured according to the measurement rule), as specified in 3GPP TS36.133V14.1.0(2016-09), T_{measure,ProSe_Relay_Intra}Is equal to four. By the above SD-RSRP measurement operationIn turn, the remote device can select or reselect an appropriate ProSe relay device.

However, for the FeD2D, the wearable device is typically carried with a smartphone. The smartphone may be used as a relay device to assist the wearable device (i.e., the remote device). Since the remote device and the relay device often move together. It can be reasonable to assume that the selection result of the relay device generally remains unchanged. Therefore, frequent searches and measurements for candidate relay devices are generally not necessary. In this case, the search for candidate relay devices and the measurement operation of SD-RSRP in the related art are excessive, which causes a waste of power consumption of the remote device.

Therefore, there is a need for an efficient energy saving scheme for the selection and reselection of ProSe relay devices for remote devices. According to the paired movement characteristics of the wearable device, the search and measurement period of the candidate relay device can be extended to reduce the search and measurement operation of SD-RSRP for the candidate relay device to save power consumption of the remote device.

To address at least in part these and other potential problems, in accordance with embodiments of the present disclosure, a remote device is allowed to adjust the search period of its candidate relay devices and the period of SD-RSRP measurements. Once the remote device selects a relay device, it begins evaluating whether the cycle extension condition is met. If this condition is met, the remote device extends the search period of its candidate relay device and the period of the SD-RSRP measurement. According to the method, the remote device may measure the SD-RSRP of the candidate relay device with one measurement period in response to searching for the candidate relay device. Based on the measurements of the SD-RSRP, a relay device is selected from the candidate relay devices to pair. Determining whether the SD-RSRP of the selected relay device satisfies a period extension condition. Extending the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices of the candidate relay devices in response to the SD-RSRP of the selected relay device satisfying a period extension condition.

In this way, the period for the remote device to search for the candidate relay device and measure its SD-RSRP can be extended, reducing the search for the candidate relay device and the measurement operation of SD-RSRP to provide the power saving gain of the remote device. Several example embodiments of the present disclosure will be described below with reference to the accompanying drawings.

Fig. 1 illustrates an example communication network 100 in which embodiments of the present disclosure may be implemented. The communication network 100 includes a network device 130 as well as terminal devices, i.e., a remote device 110 and a relay device 120. Network device 130 may communicate with remote device 110 and relay device 120. Accordingly, the remote device 110 and the relay device 120 may also communicate with each other. It should be understood that the number of network devices and terminal devices shown in fig. 1 is for illustration purposes only and is not intended to be limiting. Communication network 100 may include any suitable number of network devices and terminal devices.

As shown, in this example, relay device 110 is closer to network device 130, while remote device 120 is farther from network device 130. It should be understood that this is by way of example only and not by way of limitation. Remote device 110 and relay device 120 may have any near-far positional relationship with network device 130. For example, in the context of one embodiment of the present disclosure, remote device 110 and relay device 120 have nearly equal distances to network device 110 as they are carried together by a carrier (e.g., a user).

According to one embodiment of the present disclosure, the remote device 110 may select the relay device 120 as the relay device 120 paired with the remote device 110 by searching for the relay device 120 and measuring the SD-RPSP of the relay device 120. It should be understood that although not shown in fig. 1, there may be multiple relay devices in the network of fig. 1, and relay device 120 is the one selected to pair with remote device 110 from the multiple relay devices present in network 100 shown in fig. 1. The schematic diagram of the network 100 shown in fig. 1 is merely exemplary, which is intended to more clearly and concisely describe the present embodiments. In addition to relay device 120 being able to pair with remote device 110, other relay devices in network 100 are also able to pair with remote device 110.

Communications in network 100 may be implemented according to any suitable communication protocol. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), third generation (3G), fourth generation (4G), and fifth generation (5G) cellular communication protocols, wireless local area network communication protocols such as Institute of Electrical and Electronics Engineers (IEEE)802.11, and/or any other protocol now known or later developed. Moreover, the communication may utilize any suitable wireless communication technique including, but not limited to, Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple Input Multiple Output (MIMO), orthogonal frequency division multiple access (OFDM), and/or any other technique now known or later developed.

According to one embodiment of the disclosure, the remote device 110 is able to search for candidate relay devices in the network 100, such as the relay device 120 in fig. 1. It should be understood that although not shown in fig. 1, there may be multiple relay devices in the network of fig. 1, and relay device 120 is the one selected to pair with remote device 110 from the multiple relay devices present in network 100 shown in fig. 1. The schematic diagram of the network 100 shown in fig. 1 is merely exemplary, which is intended to more clearly and concisely describe the present embodiments. In addition to relay device 120 being able to pair with remote device 110, other relay devices in network 100 are also able to pair with remote device 110. Once the candidate relay device is searched, the SD-RSRP of the candidate relay device may be measured in one measurement period. And selecting one relay device from all candidate relay devices to pair according to the measurement result of the SD-RSRP. For example, in fig. 1, remote device 110 selects to pair with relay device 120. After pairing, the remote device 110 selects to have a pairing move feature with the relay device 120, activating detection of the cycle extension, i.e., determining whether the SD-RSRP of this selected relay device 120 meets the cycle extension condition. In this process, the SD-RSRP of the candidate relay device is measured still in the original measurement period. Upon determining that the SD-RSRP of the selected relay device 120 satisfies the period extension condition, the measurement period for measuring the SD-RSRP of the selected relay device 120 and other relay devices among the candidate relay devices is extended. Embodiments of this aspect will be described in detail later.

The principles and specific embodiments of the present disclosure will be described in detail below with reference to fig. 2 to 5. Referring first to fig. 2, a flow diagram of an example communication method 200 is shown, in accordance with certain embodiments of the present disclosure. It is to be appreciated that the method 200 can be implemented, for example, at the remote device 110 as shown in FIG. 1. For ease of description, the method 200 is described below in conjunction with FIG. 1.

In one embodiment of the present disclosure, remote device 110 searches for relay devices within coverage to discover and pair with a corresponding relay device. Here, the relay devices within the coverage are referred to as candidate relay devices. As shown, at 205, when the remote device 110 searches for a candidate relay device, the candidate relay device is measured at one measurement period.

At 210, one relay device 120 is selected from the candidate relay devices to pair with the relay device 120 according to the measurement result of SD-RSRP of the candidate relay devices obtained by the measurement. It should be noted that the length of the measurement period may be preconfigured for the remote device 110, or may be received from the network device 100 associated with the remote device 110.

At 215, it is determined whether the SD-RSRP of the selected relay device satisfies a period extension condition. If the decision at 215 is yes, i.e., the SD-RSRP of the selected relay device satisfies the period extension condition, then at 220, the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices in the candidate relay devices is extended. If the decision at 215 is no, i.e., the SD-RSRP of the selected relay device does not satisfy the period extension condition, then the measurement periods of the SD-RSRP of the selected relay device and other relay devices in the candidate relay devices are not extended. In fig. 2, if the determination at 215 is negative, the process may be returned to 205 for a new round of measurement and determination. It is noted that the process may be returned to 205 in accordance with some embodiments of the present disclosure. According to other embodiments of the present disclosure, the process may also end here.

Referring again to 215 in fig. 2, after pairing, the SD-RSRP of the selected relay device 120 is measured, still at the initial measurement period, according to one embodiment of the present disclosure. At the same time, the remote device 110 also measures the SD-RSRP of other ones of the candidate relay devices at the initial measurement period. The remote device 110 then compares the SD-RSRP of the selected relay device 120 with the SD-RSRPs of the other relay devices in the candidate relay devices. The cycle extension condition is satisfied if the SD-RSRP of the selected relay device 120 is continuously higher than the SD-RSRPs of the other relay devices among the candidate relay devices for a predetermined period of time, as derived from the measurement result. Further, according to one embodiment of the present disclosure, after pairing, the SD-RSRP of the selected relay device 120 is still measured at the initial measurement period. The cycle extension condition is also fulfilled if the SD-RSRP of the selected relay device 120 continues to be above a predefined threshold for a predetermined period of time, as derived from the measurement results. It should be noted that the predetermined SD-RSRP threshold may be pre-configured for the remote device 110, or may be received from a network device (e.g., the base station 100 in fig. 1) associated with the remote device 110.

Fig. 3 illustrates a schematic diagram of cycle extension according to certain embodiments of the present disclosure. As shown in fig. 3, at 310. The SD-RPSP measurement is always performed by the remote device on the relay device with a measurement period T1 regardless of whether before or after the remote device selects the relay device, and the length T1 of the measurement period is always unchanged at a subsequent time. And at 320, the remote device performs SD-RPSP measurements on the relay device with a measurement period T1 before the remote device selects the relay device. After the remote device selects the relay device, the remote device temporarily makes several SD-RPSP measurements for the relay device with a measurement period T1. The cycle extension is performed once the remote device determines that the cycle extension condition is met, i.e. the SD-RSRP of the selected relay device, which has been described in detail above, is continuously higher than the SD-RSRP of the other relay devices of the candidate relay devices for a predetermined period of time or the SD-RSRP of the selected relay device is continuously higher than a pre-given threshold for a predetermined period of time. As shown at 320, the measurement period is extended from T1 to T2. The remote device may also repeatedly make the determination of whether the cycle extension condition is satisfied. For example, the remote device now makes several SD-RPSP measurements with an extended measurement period, T2, on the relay device. Once the remote device determines that the cycle extension condition is satisfied, cycle extension is performed again. As shown at 320, the measurement period is extended from T2 to T3. In this way, the remote device automatically adjusts its period for candidate terminal device search and SD-RSRP measurement once the period extension condition is met. It should be noted here that, although the above description has been made of the cycle extension with the measurement cycle for measuring the SD-RSRP of the candidate relay device. However, the period shown in fig. 3 may also be considered as a discovery period for candidate relay device search. The cycle extension scheme proposed by the present disclosure can be applied to the above two cycle extensions. In fact, the relationship between the search period of the relay device for searching candidates and the period length of the measurement period for SD-RSRP measurement is fixed, which can be adjusted together. For example, in legacy LTE, the remote device searches for candidate relay devices once per discovery period and measures SD-RSRP of the selected relay device once every four discovery periods. In other words, if the period T1 shown in fig. 3 is a candidate relay device search period, T1 corresponds to one discovery period. If the period T1 shown in fig. 3 is a measurement period of SD-RSRP, T1 corresponds to four discovery periods.

Returning again to 215 of figure 2. It should be noted here that the aforementioned period can be gradually extended. For example, when the extension condition is satisfied, the period of the remote device is changed from the original value to twice the original value. And then, for example, when the condition is further satisfied, from the doubled original value to the quadrupled original value.

According to one embodiment of the present disclosure, the search period and SD-RSRP measurement period for the selected relay device 120 can be different from the search period and SD-RSRP measurement period for other relay devices of the candidate relay devices. Once the extension condition is satisfied, the remote device can perform SD-RSRP measurement cycles on the other ones of the candidate relay devices with a cycle longer than the cycle length of the selected relay device, and can even suppress search and measurement of the other ones of the candidate relay devices by extending the length of the cycle for the other ones of the candidate relay devices to infinity.

According to one embodiment of the present disclosure, extending the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices of the candidate relay devices may be achieved by two methods. Since the relationship between the search period of the relay device for searching for the candidate and the period length of the measurement period for SD-RSRP measurement is fixed, extension of the measurement period can be achieved by extending the length of the discovery period for searching for the candidate relay device, and the multiple between the measurement period and the discovery period can also be increased. For example, the remote device searches for the relay device once every discovery period, and measures the SD-RSRP of the relay device once every four discovery periods. Assuming that the search period has a first length and the measurement period has a second length, the second length is equal to four times the first length. Thus, the extended period may be achieved by increasing the first length or by increasing the multiple between the second length and the first length.

As previously described and as can be appreciated in conjunction with 320 of fig. 3, the period may be continuously extended. For example, at 320, the cycle length has been extended to T2. The period length will be extended to T3 provided that the SD-RSRP of the selected relay device is thereafter measured with an extended measurement period and it is determined that the SD-RSRP of the selected relay device continues to satisfy the period extension condition in accordance with the actions previously described. And if the SD-RSRP of the selected relay equipment is determined to no longer meet the cycle extension condition at this time, executing a fallback action. Namely, the search for the relay device and the SD-RSRP measurement are performed again at the initial value, i.e., at the period T1 in fig. 3. According to one embodiment of the present disclosure, the case where the SD-RSRP of the selected relay device no longer satisfies the period extension condition may be that the SD-RPSP of this selected relay device is no longer the highest of all candidate relay devices, or that the value of the SD-RPSP of this selected relay device has fallen below a pre-given threshold.

It should be noted that the fallback action may occur, for example, when the relay device suddenly stops working, for example, when the relay device is a smart phone and the smart phone suddenly runs out of power. The fallback action may also occur in case an instruction is received from outside, e.g. a network device or a user associated with the remote device, to switch the connection with the remote device to another relay device. And once the fallback occurs, searching the relay equipment and performing SD-RSRP measurement again at the initial value.

It is noted that the configuration of parameters related to the cycle extension, such as thresholds for conditions of cycle extension and fallback and activation and deactivation of the proposed cycle extension procedure, can be implemented by both ways, i.e. can be preconfigured on the remote device, e.g. added to the side-link preconfiguration (SL-Preconfig), to be available for remote devices outside the coverage of the network device; it may also be set by the associated network device, e.g. eNB, through RRC signaling. Thus, the parameters of the remote device can be flexibly adjusted.

Fig. 4 illustrates a flow diagram of an example communication method 400 according to other embodiments of the present disclosure. Fig. 5 shows a schematic diagram of a cycle extension according to the example communication method 400 of fig. 4 according to other embodiments of the present disclosure. An exemplary method according to one embodiment of the present disclosure is described below in conjunction with fig. 4 and 5. Some of the details that have been described in detail in the foregoing are not repeated here.

The method 400 begins to search for candidate relay devices. At 405, SD-RSRP of the candidate relay device is measured with a period T1. Next, based on the measurement of SD-RSRP, at 410, one relay device is selected from the candidate relay devices for pairing. If a suitable relay device is selected at 410, execution continues at 415. If no suitable relay device is selected, the process returns to 405, and the search and measurement of the candidate relay device are continuously executed. At 415, SD-RSRP of the selected relay device and other relay devices of the candidate relay devices are measured, still at period T1. Thereafter, a determination is made at 420 as to whether condition C1 is satisfied. For example, in this embodiment, C1 may be, for example, the SD-RPSP of the selected relay device is higher than the SD-RPSP of all other relay devices in the candidate relay device for x T1 cycles, for example. It is noted that the remote device always performs the measurement of SD-RPSP at a period T1 until C1 is satisfied. Likewise, the value of x here may be preconfigured on the remote device or may be set by the associated network device, e.g. eNB, through RRC signaling. If it is determined at 420 that C1 is satisfied, the remote device transitions the period T1 to the period T2(T2> T1). If it is determined at 420 that C1 is not satisfied, the process returns to 415, i.e., the remote device always performs the SD-RPSP measurements at period T1. At 425, the measurement of SD-RPSP is performed at period T2. Thereafter at 430, a determination is made as to whether condition C3 is satisfied. The condition C3 may be, for example, whether a fallback condition is satisfied, e.g., the selected relay device is no longer higher than other relay devices in the candidate relay devices. If condition C3 is satisfied, the process returns to 415, i.e., the remote device always performs the SD-RPSP measurements at period T1. If condition C3 is not satisfied, then at 435, a determination is made as to whether condition C2 is satisfied. The measurement of SD-RPSP is still performed at this time with the period T2. The condition C2 may be, for example, that the SD-RPSP of the selected relay device is higher than the SD-RPSP of all other relay devices in the candidate relay device for y T2 cycles. Likewise, the y value here may be preconfigured on the remote device or may be set by the associated network device, e.g., eNB, through RRC signaling. If condition C2 is satisfied, the remote device transitions period T2 to period T3(T3> T2). Next, at 440, the measurement of SD-RPSP is performed with period T3. If condition C2 is not met, the process returns to 425, i.e., the remote device always performs SD-RPSP measurements at period T2. The process at 445 is the same as that at 430 and is not described in detail herein. It should be noted that the steps or actions of method 400 in fig. 4 are only shown for illustrating one embodiment of the present disclosure shown in fig. 4, and are not meant as limitations on the methods for implementing the present disclosure. Those skilled in the art will appreciate that any modifications, omissions, or additions may be made to the steps or acts described above without departing from the scope of the present disclosure. In some embodiments of the present disclosure, the order of the above steps or actions may also be adjusted.

A schematic diagram of the periodic variation corresponding to the method 400 of fig. 4 is shown at 500 in fig. 5. For example, when the cycle extension conditions C1 and C2 are satisfied, the cycle changes from T1 to T2 and from T2 to T3, respectively. And when the rollback condition C3 is met, the period is changed into the original period T1 again.

Fig. 6 illustrates a block diagram of an apparatus according to certain embodiments of the present disclosure. It is understood that apparatus 600 may be implemented on the side of terminal device 110 shown in fig. 1. As shown in fig. 7, apparatus 600 (e.g., terminal device 110) includes: a first measurement unit 605 configured to measure, in response to searching for a candidate relay device, side link discovery reference signal received power (SD-RSRP) of the candidate relay device with one measurement period; a selecting unit 610 configured to select a relay device from the candidate relay devices to pair based on the measurement of the SD-RSRP; a first determining unit 615 configured to determine whether the SD-RSRP of the selected relay device satisfies a period extension condition; and an extending unit 620 configured to extend the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices among candidate relay devices in response to the SD-RSRP of the selected relay device satisfying a period extension condition.

In some embodiments, the apparatus 600 may further include a receiving unit configured to receive an indication of the length of the measurement period from a network device associated with the terminal device.

In some embodiments, the first determining unit 615 may further include a second measuring unit configured to measure the SD-RSRP of the selected relay device and the SD-RSRP of other relay devices of the candidate relay devices at the measurement period; a comparing unit configured to compare the SD-RSRP of the selected relay device with the SD-RSRP of other relay devices of the candidate relay devices; and a second determining unit configured to determine that the cycle extension condition is satisfied in response to determining that the SD-RSRP of the selected relay device is continuously higher than the SD-RSRPs of the other relay devices for a predetermined period of time.

In some embodiments, the first determining unit 615 may further include a third measuring unit configured to measure the SD-RSRP of the selected relay device at the measurement period; a third determining unit configured to determine whether the SD-RSRP of the selected relay device exceeds a given SD-RSRP threshold; and a fourth determining unit configured to determine that the cycle extension condition is satisfied in response to determining that the SD-RSRP of the selected relay device continuously exceeds a given SD-RSRP threshold for a predetermined period of time.

In some embodiments, the first extension unit 620 further comprises a second extension unit configured to extend the length of the discovery period for searching for candidate relay devices.

In some embodiments, the first extending unit 620 further comprises a third extending unit configured to increase a multiple between the measurement period having a first length and the discovery period having a second length, wherein the discovery period is a period for searching for candidate relay devices, and the first length is greater than the second length.

In some embodiments, the first extending unit 620 further comprises a fourth measuring unit configured to measure the SD-RSRP of the selected relay device with an extended measurement period; a fifth determining unit configured to determine whether the SD-RSRP of the selected relay device satisfies a backoff condition; and a fifth measuring unit configured to measure the SD-RSRP of the selected relay device and the other relay devices among the candidate relay devices at the measurement period in response to the SD-RSRP of the selected relay device satisfying the backoff condition.

In some embodiments, the fifth determining unit further comprises a sixth measuring unit configured to measure the SD-RSRP of the selected relay device and the SD-RSRP of other relay devices of the candidate relay devices with an extended measurement period; a second comparing unit configured to compare the SD-RSRP of the selected relay device with the SD-RSRP of other relay devices of the candidate relay devices; and a sixth determining unit configured to determine that the fallback condition is satisfied in response to determining that the SD-RSRP of the selected relay device is not higher than the SD-RSRP of the other relay devices.

In some embodiments, the fifth determining unit further comprises a seventh measuring unit configured to measure the SD-RSRP of the selected relay device with an extended measurement period; a seventh determining unit configured to determine whether the SD-RSRP of the selected relay device exceeds a given SD-RSRP threshold; and an eighth determining unit configured to determine that the fallback condition is satisfied in response to determining that the SD-RSRP of the selected relay device does not exceed a given SD-RSRP threshold.

It should be understood that each unit recited in the apparatus 600 corresponds to each step in the method 200 described with reference to fig. 2-5, respectively. Therefore, the operations and features described above in connection with fig. 1 to 5 are also applicable to the apparatus 600 and the units included therein, and have the same effects, and detailed description is omitted here.

The elements included in apparatus 600 may be implemented in a variety of ways including software, hardware, firmware, or any combination thereof. In one embodiment, one or more of the units may be implemented using software and/or firmware, such as machine executable instructions stored on a storage medium. In addition to, or in the alternative to, machine-executable instructions, some or all of the elements in apparatus 600 may be implemented at least in part by one or more hardware logic components. By way of example, and not limitation, exemplary types of hardware logic components that may be used include Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), Application Specific Standards (ASSPs), systems on a chip (SOCs), Complex Programmable Logic Devices (CPLDs), and so forth.

The elements shown in fig. 6 may be implemented partially or wholly as hardware modules, software modules, firmware modules, or any combination thereof. In particular, in some embodiments, the procedures, methods, or processes described above may be implemented by hardware in a network device or a terminal device. For example, a network device or a terminal device may implement the method 200 with its transmitter, receiver, transceiver, and/or processor or controller.

Fig. 7 illustrates a block diagram of a device 700 suitable for implementing embodiments of the present disclosure. Device 700 may be used to implement a network device, such as network device 110 shown in FIG. 1; and/or to implement terminal devices such as

terminal devices

110 and 120 shown in fig. 1.

As shown, the device 700 includes a controller 710. The controller 710 controls the operation and functions of the device 700. For example, in certain embodiments, controller 710 may perform various operations by way of instructions 730 stored in a memory 720 coupled thereto. The memory 720 may be of any suitable type suitable to the local technical environment and may be implemented using any suitable data storage technology, including but not limited to semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems. Although only one memory unit is shown in FIG. 7, there may be multiple physically distinct memory units within device 700.

The controller 710 may be of any suitable type suitable to the local technical environment and may include, but is not limited to, one or more of general purpose computers, special purpose computers, microcontrollers, digital signal controllers (DSPs), and controller-based multi-core controller architectures. The device 700 may also include a plurality of controllers 710. The controller 710 is coupled to a transceiver 740, and the transceiver 740 may enable the reception and transmission of information by way of one or more antennas 750 and/or other components.

When device 700 is acting as end device 110, controller 710 and transceiver 740 may operate in cooperation to implement method 200 described above with reference to fig. 2. All of the features described above with reference to fig. 2 apply to the apparatus 700 and are not described in detail here.

In general, the various example embodiments of this disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Certain 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 aspects of embodiments of the disclosure have been illustrated or described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

By way of example, embodiments of the disclosure may be described in the 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, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or divided between program modules as described. Machine-executable instructions for program modules may be executed within local or distributed devices. In a distributed facility, program modules may be located in both local and remote memory storage media.

Computer program code for implementing the methods of the present disclosure may be written in one or more programming languages. These computer program codes may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the computer or other programmable data processing apparatus, cause the functions/acts specified in the flowchart and/or block diagram block or blocks to be performed. The program code may execute entirely on the computer, partly on the computer, as a stand-alone software package, partly on the computer and partly on a remote computer or entirely on the remote computer or server.

In the context of this disclosure, a machine-readable medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. 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 thereof. More detailed examples of a machine-readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical storage device, a magnetic storage device, or any suitable combination thereof.

Additionally, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking or parallel processing may be beneficial. Likewise, while the above discussion contains certain specific implementation details, this should not be construed as limiting the scope of any invention or claims, but rather as describing particular embodiments that may be directed to particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

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

Claims

1. A communication method implemented at a terminal device, comprising:

in response to the candidate relay device being searched, measuring the side link discovery reference signal received power SD-RSRP of the candidate relay device in one measurement period;

selecting a relay device from the candidate relay devices to pair based on the measurement of the SD-RSRP;

determining whether the SD-RSRP of the selected relay device satisfies a period extension condition; and

extending the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices of candidate relay devices in response to the SD-RSRP of the selected relay device satisfying a period extension condition.

2. The method of claim 1, wherein the length of the measurement period is preconfigured.

3. The method of claim 1, comprising:

receiving an indication of a length of the measurement period from a network device associated with the terminal device.

4. The method of claim 1, wherein determining whether the SD-RSRP of the selected relay device satisfies a period extension condition comprises:

measuring the SD-RSRP of the selected relay device with the SD-RSRP of other relay devices of the candidate relay devices at the measurement period;

comparing the SD-RSRP of the selected relay device with the SD-RSRP of other relay devices in the candidate relay devices; and

determining that the cycle extension condition is satisfied in response to determining that the SD-RSRP of the selected relay device is consistently higher than the SD-RSRPs of the other relay devices for a predetermined period of time.

5. The method of claim 1, wherein determining whether the SD-RSRP of the selected relay device satisfies a period extension condition comprises:

measuring the SD-RSRP of the selected relay device with the measurement period;

determining whether the SD-RSRP of the selected relay device exceeds a given SD-RSRP threshold; and

determining that the cycle extension condition is satisfied in response to determining that the SD-RSRP of the selected relay device continuously exceeds a given SD-RSRP threshold for a predetermined period of time.

6. The method of claim 1, wherein extending the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices of candidate relay devices comprises:

the length of a discovery period for searching for candidate relay devices is extended.

7. The method of claim 1, wherein extending the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices of candidate relay devices comprises:

increasing a multiple between the measurement period having a first length and the discovery period having a second length, the discovery period being a period for searching for candidate relay devices, and the first length being greater than the second length.

8. The method of claim 1, wherein extending the measurement period for measuring the SD-RSRP of the selected relay device and other relay devices of candidate relay devices comprises:

measuring the SD-RSRP of the selected relay device and other relay devices of the candidate relay devices with an extended measurement period;

determining whether the SD-RSRP of the selected relay device satisfies a fallback condition; and

in response to the SD-RSRP of the selected relay device satisfying the backoff condition, SD-RSRP of the selected relay device and other relay devices in the candidate relay devices are measured at the measurement period.

9. The method of claim 8, wherein determining whether the SD-RSRP of the selected relay device satisfies a fallback condition comprises:

measuring the SD-RSRP of the selected relay device and the SD-RSRP of other relay devices in the candidate relay devices with an extended measurement period;

determining that the fallback condition is satisfied in response to determining that the SD-RSRP of the selected relay device is not higher than the SD-RSRP of the other relay devices.

10. The method of claim 8, wherein determining whether the SD-RSRP of the selected relay device satisfies a fallback condition comprises:

measuring the SD-RSRP of the selected relay device with an extended measurement period;

determining that the fallback condition is satisfied in response to determining that the SD-RSRP of the selected relay device does not exceed a given SD-RSRP threshold.

11. A terminal device, comprising:

a transceiver, and

a controller; a transceiver coupled to the transceiver and configured to:

12. A terminal device according to claim 11, wherein the length of the measurement period is preconfigured.

13. The terminal device of claim 11, wherein the transceiver is configured to:

14. The terminal device of claim 11, wherein the controller is further configured to:

15. The terminal device of claim 11, wherein the controller is further configured to:

measuring the SD-RSRP of the selected relay device with the measurement period;

16. The terminal device of claim 11, wherein the controller is further configured to:

17. The terminal device of claim 11, wherein the controller is configured to:

18. The terminal device of claim 11, wherein the controller is further configured to:

measuring the SD-RSRP of the selected relay device and other relay devices in the candidate relay device with the extended measurement period;

19. The terminal device of claim 18, wherein the controller is further configured to:

20. The terminal device of claim 18, wherein the controller is further configured to: