WO2018171044A1

WO2018171044A1 - Beam-based communication method and apparatus

Info

Publication number: WO2018171044A1
Application number: PCT/CN2017/086119
Authority: WO
Inventors: Yaming LUO; Xiang Chen; Eddy Chiu
Original assignee: Jrd Communication Inc.
Priority date: 2017-03-23
Filing date: 2017-05-26
Publication date: 2018-09-27
Also published as: CN108632837A; CN108632837B

Abstract

A beam-based communication method and apparatus are disclosed. The beam-based communication method includes: communicating with a base station via a beam； judging whether the beam failure occurs to the beam； and communicating with the user equipment via a backup beam when the beam failure occurs to the beam. In present disclosure, the transmission performance and robustness against beam failure may be considered simultaneously, and beam-based communication with robustness against beam failure may be achieved with high performance and low delay.

Description

BEAM-BASED COMMUNICATION METHOD AND APPARATUS

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to communication technology, and in particular relate to a beam-based communication method and apparatus.

BACKGROUND

The new radio (NR) system is envisaged to operate over a frequency range up to 100 GHz, which is considered as an important technology for capacity improvement. However, there come challenges of fragile radio link and high penetration loss. To address these problems, beamforming is adopted as an essential technique. Therefore, beams play an inevitable role in the NR system.

However, due to the high penetration loss through objects and poor diffraction around object edges at high frequencies, a beam will be sensitive to a blocking. The blocking can occur either gradually or very suddenly depending on the speed of the user equipment (UE) and the motion of objects resulting in the blocking. The narrower the beams, the more chance there is for a sudden blocking to occur. In some case, the blockage happens so suddenly that beam switching may not be performed in time, and as the sudden blockage continues, the link used for control and data signals between a base station and the UE will be lost. Thus, a beam link failure occurs. A normal random-access procedure to solve the beam link failure is so time-consuming that a large delay will happen. Therefore, a random access is re-initiated directly without any preventing or recovery actions against the beam failure, then the system performance will be affected seriously. On the other hand, multi-beam transmission may increase the robustness against the beam failure. However, the always-on multi-beam transmission will occupy more spatial resources (beams) and sacrifice the transmission performance due to the power splitting.

SUMMARY

The technical problem to be solved by the present disclosure is to provide a beam-based communication method and apparatus, such that the problem in the prior art may be solved, in which the transmission performance and robustness against beam failure may be considered simultaneously.

In order to solve the above-mentioned problems, in accordance with a first aspect, the present disclosure provides a beam-based communication method, and the method includes: communicating with a user equipment via a beam； determining whether the beam failure occurs to the beam； and communicating with the user equipment via a backup beam when the beam failure occurs to the beam.

In order to solve the above-mentioned problems, in accordance with a second aspect, the present disclosure provides a beam-based communication method, and the method includes: communicating with a base station via a beam； determining whether the beam failure occurs to the beam； and communicating with the user equipment via a backup beam when the beam failure occurs to the beam.

In order to solve the above-mentioned problems, in accordance with a third aspect, the present disclosure provides a beam-based communication apparatus, and the apparatus includes a processor and communication circuit, wherein the processor is connected to the communication circuit, and the processor is configured for executing programs to perform the method provided in accordance with the first aspect or the method provided in accordance with the second aspect.

The subsequent advantages of the present disclosure may be achieved: the backup beams may be adopted for communication in the situation that a beam failure occurs to the beams via which the base station /user equipment communicates with the user equipment /base station. When a sudden beam failure happens and continues, compared with the directly re-initiating random access in the prior art, communication via the backup beams may avoid the beam link failure and the subsequent random access caused as the beams to which a beam failure occurs are continuously used, and may reduce latency. Compared with the multi-beam transmission in the prior art, the backup beams are adopted only in case that a beam failure occurs to the beams, effectively reducing the occupation of spatial domain resource and improving transmission performance. Thus the transmission performance and robustness against beam failure may be considered simultaneously, and beam-based communication with robustness against beam failure may be achieved with high performance and low delay.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of a beam-based communication method according to a first embodiment of the present disclosure.

FIG. 2 is a flow chart of a beam-based communication method according to a second embodiment of the present disclosure.

FIG. 3 is a flow chart of a beam-based communication method according to a third embodiment of the present disclosure.

FIG. 4 is a flow chart of a beam-based communication method according to a fourth embodiment of the present disclosure.

FIG. 5 is a flow chart of a beam-based communication method according to a fifth embodiment of the present disclosure.

FIG. 6 is a flow chart of a beam-based communication method according to a sixth embodiment of the present disclosure.

FIG. 7 is a flow chart of a beam-based communication method according to a seventh embodiment of the present disclosure.

FIG. 8 is a flow chart of a beam-based communication method according to an eighth embodiment of the present disclosure.

FIG. 9 is a judging flow chart when a beam failure occurs to a default beam carrying a downlink control channel in accordance with the eighth embodiment of the present disclosure.

FIG. 10 is a judging flow chart when a beam failure occurs to a default beam carrying an uplink control channel in accordance with the eighth embodiment of the present disclosure.

FIG. 11 is a judging flow chart when a beam failure occurs to a default beam carrying a physical downlink shared channel in accordance with the eighth embodiment of the present disclosure.

FIG. 12 is a flow chart of a beam-based communication method according to a ninth embodiment of the present disclosure.

FIG. 13 is a flow chart of a beam-based communication method according to a tenth embodiment of the present disclosure.

FIG. 14 is a flow chart of a beam-based communication method according to an eleventh embodiment of the present disclosure.

FIG. 15 is a flow chart of a beam-based communication method according to a twelfth embodiment of the present disclosure.

FIG. 16 is a flow chart of a beam-based communication method according to a thirteenth embodiment of the present disclosure.

FIG. 17 is a flow chart of a beam-based communication method according to a fourteenth embodiment of the present disclosure.

FIG. 18 is a flow chart of a beam-based communication method according to a fifteenth embodiment of the present disclosure.

FIG. 19 is a flow chart of a beam-based communication method according to a sixteenth embodiment of the present disclosure.

FIG. 20 is a flow chart of a beam-based communication method according to a seventeenth embodiment of the present disclosure.

FIG. 21 is a flow chart of a beam-based communication method according to an eighteenth embodiment of the present disclosure.

FIG. 22 is a flow chart of a beam-based communication method according to a nineteenth embodiment of the present disclosure.

FIG. 23 is a schematic view of a beam-based communication apparatus according to a first embodiment of the present disclosure.

FIG. 24 is a schematic view of a beam-based communication apparatus according to a second embodiment of the present disclosure.

FIG. 25 is a schematic view of a beam-based communication apparatus according to a third embodiment of the present disclosure.

DETAILED DESCRIPTION

Referring to FIG. 1, the execution subject of the beam-based communication method in accordance with a first embodiment may be a base station. The base station may be connected to a core network, and has a wireless communication with a user equipment, providing communication coverage for a corresponding region. The base station may be a macro base station, a micro base station, a pico base station or femtocell. In some embodiments, the base station may be called as the wireless base station, access point, B node, long term B node (eNodeB, eNB) , gNB or other suitable terms. As shown in FIG. 1, the method may include the following blocks in present embodiment.

In block S11, the base station may communicate with a user equipment via a beam.

Initially-used beams are default beams. The default beams may include at least one uplink default beam and at least one downlink default beam. The uplink default beam is configured for transmitting data and control signalings to the base station by the user equipment in a default state. The downlink default beam is configured for transmitting data and control signalings to the user equipment by the base station in the default state. The base station may transmit a downlink signal /channel to the user equipment via the downlink default beam, and /or receive an uplink signal /channel transmitted by the user equipment via the uplink default beam.

Uplink /downlink data and control signalings may be carried in a same uplink /downlink default beam, and may also be respectively carried in different uplink /downlink default beams. Generally, different beams may carry different signals /channels when the number of the uplink /downlink default beams is greater than one.

Narrower coverage of a beam, more easily a beam failure happens. In one embodiment, Uplink /downlink data and control signalings may be respectively carried in different uplink /downlink default beams, and the coverage of the beam carrying control signalings is larger than that of the beam carrying data. In this way the possibility that causes a control signaling transmission error shall be reduced.

In block S12, the base station may determine whether a beam failure occurs to the beam.

The trigger conditions to decide that a beam failure occurs to a beam may include at least one of which the number of times that a communication error occurs continuously is greater than or equal to a first threshold, a duration in which the communication error occurs continuously is greater than or equal to a second threshold, and a beam failure message from the user equipment is received. In addition, the trigger conditions to decide that a beam failure occurs to a beam may also include that beam performance is lower than a preset value, and /or a beam link failure occurs.

That the communication error occurs continuously herein doesn’t mean that the communication error is continuous without termination in time domain, but means that there doesn’t occur another communication error between any adjacent two communication errors.

The beams to which a beam failure occurs may be one or more uplink /downlink default beams. The base station may respectively determine each uplink /downlink default beam, when the number of uplink /downlink default beams is greater than one. The base station may also determine at least two uplink /downlink default beams together, such as all the uplink /downlink default beams.

Channels carried in the beam to which a beam failure occurs may include at least one of a Physical Downlink Control Channel (PDCCH) , a Physical Hybrid-ARQ Indicator Channel (PHICH) , a Physical Downlink Shared Channel (PDSCH) , a Physical Uplink Control Channel (PUCCH) and a Physical Uplink Shared Channel (PUSCH) .

Block S13 may be performed when the beam failure occurs to the beam, the subsequent communication via the default beam may be continued when the beam failure doesn’t occur to the beam.

In block S13, the base station may communicate with the user equipment via a backup beam.

The backup beams may be used to replace a part of default beams (at least including beam to which a beam failure occurs) or all the default beams. And the backup beams may be different from the replaced default beams. The performances of the backup beams may support the normal use or are superior to that of the replaced default beams.

Which uplink /downlink default beams to which a beam failure occurs may be further identified and only beams to which a beam failure occurs may be replaced, when the number of the uplink /downlink default beams is greater than one, and candidate beams (to which the base station may switch) for different uplink /downlink default beams are different. In this way, resource consumption caused by the switching may be reduced.

The base station and/or the user equipment will need to be switched to backup beams from the replaced default beams. The switching process may be performed independently by the base station or the user equipment, and also be performed with assistances or indications of the other one.

With the implementation of the above embodiment, the backup beams may be adopted for communication in the situation that a beam failure occurs to the beams via which the base station communicates with the user equipment is decided. When a sudden beam failure happens and continues, compared with the directly re-initiating random access in the prior art, communication via the backup beams may avoid the beam link failure and the subsequent random access caused as the beams to which a beam failure occurs are continuously used, and may reduce latency. Compared with the multi-beam transmission in the prior art, the backup beams are only adopted in case that a beam failure occurs to the beams, effectively reducing the occupation of spatial domain resource and improving transmission performance. Thus the transmission performance and robustness against beam failure may be considered simultaneously, and a beam-based communication with robustness against beam failure may be achieved with high performance and low delay.

Referring to FIG. 2, a beam-based communication method according to a second embodiment is based on the beam-based communication method according to the first embodiment. Whether the beam failure occurs to the beam is determined according to whether a beam failure message is received and times and/or duration that a communication error occurs continuously. The beam-based communication method in the second embodiment is further extended based on that in the first embodiment of the present disclosure, thus the same details with that in the first embodiment will not be described again herein. The beam-based communication method in the second embodiment may include the following blocks.

In block S111, the base station may transmit a downlink signal /channel to the user equipment via a first beam.

The downlink signal /channel may be configured for transmitting downlink data and/or control signalings. The first beam is one of the downlink default beams.

In general, the downlink signals /channels may include a PDCCH. The base station transmits downlink control information (DCI) via the PDCCH to perform dynamic and /or semi-persistent scheduling to allocate radio resource for the user equipment. The user equipment is in response to the downlink signal /channel and transmits an uplink signal /channel to the base station through the allocated radio resource under the normal circumstance. The uplink signal /channel may be configured for carrying uplink data or control signalings.

In block S112, the base station may determine whether a beam failure message from the user equipment is received.

Block S115 may be performed when the beam failure message is received, otherwise block S113 may be performed.

In block S113, the base station may determine whether a communication error occurs.

The communication error may include not-receiving the uplink signal / channel transmitted by the user equipment in response to the downlink signal /channel within a preset time period, and /or receiving a negative acknowledgement transmitted by the user equipment in response to the downlink signal /channel.

The preset time period may mean that moments corresponding to the allocated radio resource. The preset time period is the moments at which the radio resource allocated by the base station occupies in time domain, when the allocated radio resource are used for uplink transmission. The preset time period lies after the moment at which the radio resource allocated by the base station occupies in time domain, and there is an interval with specified duration between the preset time period and the moment, when the allocated radio resources are used for downlink data.

Block S114 may be performed when the communication error occurs, otherwise the subsequent communication with the user equipment via the default beam may be continued, and a timeout value may be initialized when the timeout value may be adopted to calculate the number of the times that the communication error occurs continuously.

In block S114, the base station may determine whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold and /or the duration in which the communication error occurs continuously is greater than or equal to the second threshold, when the communication error occurs.

The base station may distinguish different types of communication errors in calculating the number of the times /duration, that is to say, the base station respectively calculates the number of times /duration of each type of the communication error, and may also not distinguish different types of communication errors, if there is not just one type of the communication error such as not-receiving the uplink signal /channel and receiving the negative acknowledge.

The user equipment may also discover the communication error when the base station determines whether the communication error occurs. Both may start to calculate the number of times that the communication error occurs continuously and compare the number of times with a corresponding threshold. In one embodiment, the first threshold adopted by the base station may be greater than the threshold used by the user equipment, such that the user equipment may confirm the beam to which a beam failure occurs at advance and report the beam failure message, reducing the required time for the judgment process.

The base station may initialize a timer to start timing when the communication error occurs firstly. In the subsequent process, the base station may stop timing and reset the timer with the initial value when the communication error doesn’t occur, and continue to time and calculate the difference between the current value of the timer and the initial value as the duration when the communication error occurs. The base station may also calculate the difference between the last moment and the first moment when the communication error occurs continuously as the duration.

Block S115 may be performed when the times is greater than the first threshold and /or the duration is greater than the second threshold, otherwise the block S111 may be performed to re-transmit the downlink signal /channel via the first beam continuously, repeating the above process.

In block S115, the base station may determine that the beam failure occurs to the beam.

In block S116, the base station may transmit the downlink signal /channel to the user equipment via the backup beam, and /or receive an uplink signal /channel transmitted by the user equipment via the backup beam.

Referring to FIG. 3, a beam-based communication method according to a third embodiment is based on the beam-based communication method according to the first embodiment. Whether the beam failure occurs to the beam is determined according to whether a beam failure message is received and the number of times and / or duration in which a communication error occurs continuously. Compared with that in the second embodiment, the beam-based communication method in the third embodiment has a difference which is that firstly-determining whether the communication error occurs and secondly-determining whether the beam failure message is received. The same details with that in the first embodiment will not be described again herein. The beam-based communication method in the third embodiment may include the following blocks.

In block S121, a downlink signal /channel may be transmitted to the user equipment via a first beam.

In block S122, the base station may determine whether the communication error occurs.

Block S123 may be performed when the communication error occurs, otherwise block S124 may be performed and a timeout value may be initialized when the timeout value may be adopted to calculate the number of the times that the communication error occurs continuously.

In block S123, the base station may determine whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold and /or the duration in which the communication error occurs continuously is greater than or equal to the second threshold, when the communication error occurs.

Block S125 may be performed when the number of the times is greater than the first threshold and /or the duration is greater than the second threshold, otherwise the block S121 may be performed to re-transmit the downlink signal /channel via the first beam continuously, and then the above process may be repeated.

In block S124, the base station may determine whether a beam failure message reported by the user equipment may be received.

Block S125 may be performed when the beam failure message is received, otherwise the base station may continue to communicate with the user equipment via the default beam.

In block S125, the base station may decide that the beam failure occurs to the beam.

In block S126, the base station may transmit the downlink signal /channel to the user equipment via the backup beam, and /or receive an uplink signal /channel transmitted by the user equipment via the backup beam.

In the beam-based communication methods of the second and third embodiment of the present disclosure, the process to determine whether a beam failure message is received and the process to determine whether the communication error occurs are independent, while in some embodiment, the base station may simultaneously perform those both determining processes. The base station may transmit the beam failure message at the same time when user equipment feeds back the uplink signal /channel, for example. The base station may also try to receive the uplink signal /channel fed by the user equipment at a preset moment, and then directly simultaneously perform those both determining processes according to received results (which are whether successfully receiving and the content of the received uplink signal /channel) .

Referring to FIG. 4, a beam-based communication method according to a fourth embodiment is based on the beam-based communication method according to the first embodiment. Whether the beam failure occurs to the beam is determined according to times and /or duration that a communication error occurs continuously. Compared with that in the second embodiment, the beam-based communication method in the fourth embodiment has a difference which is that determining whether the beam failure message is received may be omitted. The same details with that in the second embodiment will not be described again herein. The beam-based communication method in the third embodiment may include the following blocks.

In block S131, a downlink signal /channel may be transmitted to the user equipment via a first beam.

In block S132, the base station may determine whether a communication error occurs.

Block S133 may be executed when the communication error occurs, otherwise block S134 may be executed, and a timeout value may be initialized when the timeout value may be adopted to calculate the number of the times that the communication error occurs continuously.

In block S133, the base station may judge whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold and /or the duration in which the communication error occurs continuously is greater than or equal to the second threshold, when the communication error occurs.

Block S134 may be executed when the number of the times is greater than the first threshold and /or the duration is greater than the second threshold, otherwise the block S131 may be executed to re-transmit the downlink signal /channel via the first beam continuously, repeating the above process.

In block S134, the base station may decide that the beam failure occurs to the beam.

In block S135, the base station may transmit the downlink signal /channel to the user equipment via the backup beam, and /or receive an uplink signal /channel transmitted by the user equipment via the backup beam.

Referring to FIG. 5, a beam-based communication method according to a fifth embodiment is based on the beam-based communication method according to the second, third and fourth embodiments. The step to determine whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold may include the following blocks.

In block S1110, the base station may decrement the timeout value by one.

The initial value of the timeout value is the first threshold. The base station may initialize the timeout value before a first preset time. When the communication error has occurred and no communication errors occur in the subsequent process, the base station initializes the timeout value, that is say, the timeout value may be reset as the initial value. Of course the base station may also initialize the timeout value each time deciding that no communication errors occur.

In block S1120, the base station may judge whether the timeout value is greater than or equal to 0.

Block S1130 may be executed when the timeout value is greater than or equal to 0, otherwise the subsequent blocks may be executed continuously to re-transmit the downlink signal /channel such that the circulation may be continued.

In block S1130, the base station may determine that the number of the times is greater than or equal to the first threshold.

The process may be continued. The initial value and the target value of timeout value in this embodiment are just schematic. In actual application, the initial value and the target value may be set with requirements, as long as the initial value is greater than the target value and the difference between the initial value and the target value is greater than the first threshold.

Referring to FIG. 6, a beam-based communication method according to a sixth embodiment is based on the beam-based communication method according to the second, third and fourth embodiments. The step to determine whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold may include the following blocks.

In block S1210, the base station may increment the timeout value by one.

The initial value of the timeout value is 0. The base station may initialize the timeout value before a first preset time. When the communication error has occurred and no communication errors occur in the subsequent process, the base station may initialize the timeout value. Of course the base station may also initialize the timeout value each time deciding that no communication errors occur.

In block S1220, the base station may judge whether the timeout value is greater than or equal to the first threshold.

Block S1230 may be executed when the timeout value is greater than or equal to the first threshold, otherwise the subsequent blocks may be executed continuously to re-transmit the downlink signal /channel such that the circulation may be continued.

In block S1230, the base station may determine that the number of the times is greater than or equal to the first threshold.

Referring to FIG. 7, a beam-based communication method according to a seventh embodiment is based on the beam-based communication method according to the first embodiment. As shown in FIG. 7, the beam-based communication method may further include the following block after the block S12.

In block S14, the base station may transmit a beam-switching instruction to the user equipment when the beam failure occurs to the beam

The beam-switching instruction may be used for informing the user equipment to switch to the backup beam from the uplink default beam to transmit the uplink signal /channel. The user equipment may determine the backup beam according to the beam-switching instruction. The beam-switching instruction may include a failure type and /or information of the backup beam. The failure type is configured for indicating what signals /channels carried in the beam to which a beam failure occurs. A beam carrying the beam-switching instruction may be a default beam or a backup beam. The executed sequence of the blocks S14 and S13 may be not restrictive herein, for example, the base station may transmit the beam-switching instruction to the user equipment via the backup beam. The method in the seventh embodiment may be combined with that in any one of the above embodiments.

In one embodiment, the user equipment may switch to the backup beam without any indications of the base station such that the signaling overhead may be reduced and the delay may be shortened. For example, the user equipment may transmit the beam failure message to the base station via the backup beam directly.

Referring to FIG. 8, a beam-based communication method according to an eighth embodiment is based on the beam-based communication method according to the first embodiment. As shown in FIG. 8, the beam-based communication method may further include the following block between blocks S12 and S13.

In block S15, the base station may determine what signals /channels carried in the beam to which a beam failure occurs according to at least one of trigger conditions to determine that a beam failure occurs to the beam, whether a communication error occurs, failure types of the received beam failure message and types of the communication error.

The number of uplink default beams and /or the number of downlink default beams are /is greater than one, and different default beams may carry different signals /channels. The base station may determine failure signals /channels and then determine that a beam failure occurs to the beam, so as to conveniently select the backup beam in subsequent process. The method in the eighth embodiment may be combined with that in any one of the above embodiments. In one embodiment, the block S15 may be executed at the same time the block S12 may be executed, that is to say, the base station may identify which beam failure occurs to the beam at same time as determining that the beam failure occurs to the beam.

In general, after an initial access process has been performed, communications between the base station and the user equipment may mainly include that the base station requests the user equipment to perform uplink transmission (reporting uplink data and /or control signalings) , the base station transmits downlink data to the user equipment, and the user equipment directly performs uplink transmission in case that the user equipment has not uplink grant. The adopted channels may mainly include a PDCCH, a PDSCH, a PUCCH and a PUSCH.

Under the circumstance of no transmission errors, requesting the user equipment to perform uplink transmission by the base station may include that the base station transmits DCI to the user equipment using the PDCCH. DCI may be configured for indicating the user equipment to report data and /or control signalings, including the allocated radio resource, a modulation method and Hybrid Automatic Repeat request (HARQ) ID and so on. The user equipment may report uplink data and /or control signalings using PUCCH and /or PUSCH according to the DCI, after receiving the PDCCH and decoding the DCI. Wherein the uplink data may be carried in PUSCH, and the uplink control signalings may be carried in PUCCH or PUSCH.

Under the circumstance of no transmission errors, transmitting downlink data to the user equipment by the base station may include that the base station transmits DCI to the user equipment using a PDCCH. DCI may be configured for indicating the user equipment to report data and /or control signalings, including the allocated radio resource, a modulation method and HARQ ID and so on. After receiving the PDCCH and decoding the DCI, the user equipment may try to receive a PDSCH according to the DCI, and transmit a corresponding acknowledgement (ACK) or negative acknowledgement (NACK) to the base station according to whether the PDSCH is received after a specified time period.

Under the circumstance of no transmission errors, directly performing uplink transmission by the user equipment in case that the user equipment does not have uplink grant may include that the user equipment transmits an uplink control signaling to the base station using PUCCH. The base station transmits corresponding DCI to the user equipment using PDCCH after receiving the uplink control signaling. For example, the uplink control signaling may be a Scheduling Request (SR) . DCI may include PUSCH resource allocated for the user equipment.

The specific determining process, during which a beam failure occurs to one default beam, and downlink control channels (including a PDCCH and a PHICH) and uplink channels (including a PUCCH and a PUSCH) are carried in different default beams, will be described with reference to the accompanying drawings. In a following example, communication errors of the base station may just include not-receiving the uplink signal /channel transmitted by the user equipment within a preset time period, and except for a beam expressed specifically, a beam used in the communication belongs to default beams.

Referring to FIG. 9, DCI may be configured for indicating uplink transmission and that a beam failure occurs to a beam carrying downlink control channel.

In block S151, the base station transmits PDCCH to the user equipment, and the user equipment fails to receive.

As there a beam failure occurs to the beam carrying PDCCH, the user equipment fails to receive. Thus the uplink transmission will not be performed as DCI.

In block S152, the base station initializes a timeout value as the first threshold.

The first threshold is an integer greater than 1. The executed sequence of the blocks S152 and S151 is only schematic. In fact, the block S152 may also be executed before block S151 or at same time with block S151.

In block S153, the base station fails to receive a corresponding uplink data and /or control signalings at a preset moment.

The base station receives unsuccessfully, which means that a communication error occurs.

In block S154, the base station decrements the timeout value by one.

In block S155, the base station transmits PDCCH and PHICH with NACK to the user equipment, and the user equipment fails to receive.

In block S156, the base station fails to receive corresponding uplink data and /or control signalings.

In block S157, the base station decrements the timeout value by one.

In block S158, the base station judges whether the timeout value is equal to 0.

Block S159 will be executed when the timeout value is equal to 0, otherwise the block S155 will be executed to repeatedly execute the above blocks.

In block S159, the base station decides that the beam failure occurs to the beam.

When DCI is used for indicating downlink data and that a beam failure occurs to a beam carrying downlink control channels, compared with that in FIG. 9, the difference may be that the base station will transmit PDSCH after transmitting PDCCH each time, and will not transmit PHICH with the NACK when re-transmitting PDCCH, which will not be described in details.

As it can be seen, the user equipment can know that a beam failure occurs to the beam carrying downlink control channels, only when receiving downlink control channels carried in the backup beam. If the user equipment always receives downlink control channel only via the default beam, the user equipment will also fail to receive PDCCH, even if the base station switches to the backup beam from the beam to which a beam failure occurs. In addition, the user equipment may also need to directly receive a beam-switching instruction carried in the backup beam. Of course the beam-switching instruction can be carried in PDCCH. Thus in the communication, the user equipment requires to simultaneously monitor the default beam carrying PDCCH /beam-switching instruction and corresponding candidate beams to attempt to receive the PDCCH/beam-switching instruction.

The specific determining process, during which the user equipment directly performs uplink transmission in case that the user equipment does not have uplink grant, is similar to that in FIG. 9, and the difference is that the relationship of transmitting-receiving between the base station and the user equipment is opposite to that in FIG. 9, and the used channel is altered as PUCCH correspondingly. In addition, as the user equipment fails to determine when the base station feeds back when directly performing the above transmission, the preset time used by the user equipment during the judging process is obviously longer than that used by the base station. Similarly, the base station requires to simultaneously monitor the default beam (e.g. the second beam) carrying PUCCH /beam fail message and corresponding candidate beams to attempt to receive the PUCCH/beam fail message.

Referring to FIG. 10, DCI may be configured for indicating uplink transmission and that a beam failure occurs to a beam carrying downlink control channel.

In block S161, the base station transmits PDCCH to the user equipment, and the user equipment receives successfully.

In block S162, the user equipment decodes the DCI.

In block S163, the user equipment transmits uplink data and /or control signalings to the base station via PUSCH according to the DCI, and the base station fails to receive.

As there a beam failure occurs to the beam carrying uplink channel, the base station fails to receive corresponding uplink data and /or control signalings. Thus the base station discovers the communication error.

In block S164, the base station decrements a first timeout value by one.

The first timeout value is initially set as the first threshold before block S164 is executed.

In block S165, the base station transmits PDCCH and PHICH with NACK to the user equipment, and the user equipment receives successfully.

The user equipment discovers the communication error as receiving PDCCH and PHICH with NACK. The PHICH with NACK is used for indicating a PUSCH transmission failure. The PDCCH may also carry a control signaling used for indicating uplink re-transmission.

In block S166, the user equipment decrements a second timeout value by one and decodes the DCI.

The second timeout value is initially set as a preset threshold before the block S166 is firstly executed. The first threshold is greater than the preset threshold, and the difference between the first threshold and the preset threshold is greater than 1.

In block S167, the user equipment re-transmits uplink data and /or control signalings to the base station via PUSCH, and the base station fails to receive.

In block S168, the user equipment judges whether the second timeout value is equal to 0.

Block S171 will be executed when the second timeout value is equal to 0, otherwise the block S165 will be executed to repeatedly execute the above blocks.

In block S169, the base station decrements the first timeout value by one.

In block S170, the base station judges whether the first timeout value is equal to 0.

The block S165 will be executed to repeatedly execute the above blocks when the first timeout value is not equal to 0. As the initial value of the first timeout value is greater than the initial value of the second timeout value, and difference therebetween is greater than 1, the user equipment has decided that the beam failure occurs to the beam before the first timeout value reaches 0.

In block S171, the user equipment determines that the beam failure occurs to the beam.

In block S172, the user equipment transmits a beam failure message via the backup beam.

The beam failure message may include failure type and /or information of the backup beam. The failure type is used for indicating what signals/channels carried in the beam to which the beam failure occurs. The user equipment may also simultaneously transmit uplink data via the backup beam.

The executed sequence of blocks S167 and S168 in FIG. 10 is just schematic. In fact, blocks S167 and S168 may be executed simultaneously or the block S168 may be executed before block S168. The executed sequence of blocks S168, S169 and S170 may be not restrictive.

Both the base station and the user equipment in FIG. 10 calculate the number of the times that the communication error occurs continuously. In fact, the base station may also not calculate the number of the times that the communication error occurs continuously, but duration in which the communication error occurs continuously. At this time, to ensure that the base station can receive the reported beam failure message before the duration reaches the second threshold, the second threshold may be greater than the theoretical largest time of which the number of the times that the communication error occurs continuously determined by the user equipment reaches the preset threshold.

When DCI is used for indicating downlink data and that a beam failure occurs to a beam carrying downlink control channels, compared with that in FIG. 10, the difference lies in that the base station will transmit PDSCH after transmitting PDCCH each time, and the uplink channel received successfully by the base station via the backup beam may be PUCCH or PUSCH. When DCI is used for indicating transmission of the uplink control signaling, the user equipment selects PUCCH to transmit the uplink control signaling, and a beam failure occurs to the beam carrying uplink channel, compared with that in FIG. 10, the difference thereof lies in that the base station will not transmit PHICH with the NACK. At this time, the base station may transmit a control signaling used for indicating uplink re-transmission, and the uplink channel received successfully by the base station via the backup beam may be PUCCH or PUSCH, after the base station decides that the beam failure occurs to the beam,

What can be seen with reference to FIGs. 9 and 10, as for the base station, the communication error may be caused by a beam failure of a beam carrying downlink control channel or uplink channel. When a value obtained by subtracting the initial value of the second timeout value from the initial value of the first timeout value is less than or equal to 1, there appears a possibility that the base station receives the beam failure message only after deciding that the beam failure occurs to the beam according to the continuous times of the communication error. At this time, the base station fails to identify which beam carrying downlink control channel and uplink channel is blocked.

As the user equipment needs to transmit the beam failure message via the backup beam when a beam failure occurs to the beam carrying the uplink channel, in order to avoid missing the beam failure message, the beams, via which the base station judges whether the beam failure message reported by the user equipment is received or the communication error occurs after re-transmitting downlink signal /channel, may include a second beam and a candidate beam corresponding to the second beam. That is to say, the base station may monitor uplink signal /channel via the second beam and the candidate beam corresponding to the second beam during the process after discovering the communication error. The second beam may be one uplink default beam, and may be one default beam carrying uplink channel in this example. Of course, the base station may also always simultaneously monitor a default beam carrying uplink signal /channel and at least one of candidate beams thereof.

As for the base station, when PUSCH and PUCCH are carried in different beams, if the DCI is used for uplink data transmission, the uplink channel carried in the beam to which a beam failure occurs may be PUSCH, and if DCI is used for data downlink transmission or uplink control signaling transmission, the uplink channel carried in the beam to which a beam failure occurs may be PUSCH or PUCCH.

Referring to FIG. 11, DCI may be configured for indicating uplink data and that a beam failure occurs to a beam carrying PDSCH.

In block S181, the base station transmits PDCCH to the user equipment, and the user equipment receives successfully.

In block S182, the user equipment decodes the DCI.

In block S183, the base station transmits PDSCH to the user equipment, and the user equipment fails to receive.

As there is a beam failure in the beam carrying uplink channels, the user equipment fails to receive corresponding downlink data according to the DCI. Thus the user equipment discovers the communication error

In block S184, the user equipment decrements a second timeout value by one.

The second timeout value is initially set as the first threshold before block S184 is executed.

In block S185, the user equipment judges whether the second timeout value is equal to 0.

Block S188 will be executed when the second timeout value is equal to 0, otherwise the block S186 will be executed.

In block S186, the user equipment transmits NACK to the base station using PUCCH/PUSCH, and the base station receives successfully.

In block S187, the base station detects the NACK.

The NACK means that the user equipment may receive downlink data unsuccessfully and the base station requires to re-transmit to execute the block S181, executing the above blocks in circulation. In one embodiment, the base station may omit the previous corresponding PDCCH transmission when re-transmitting downlink data.

In block S188, the user equipment determines that the beam failure occurs to the beam.

In block S189, the user equipment transmits a beam failure message, and the base station receives successfully.

The beam failure message may include failure type and /or information of the backup beam. The failure type is used for indicating what signals/channels carried in the beam to which the beam failure occurs is PDSCH. The backup beam may be replaced with a default beam carrying the PCSCH.

What can be seen with reference to three examples in FIGs. 9-11, the base station can determine what signals /channels carried in the beam to which a beam failure occurs according to the trigger condition to decide that the beam failure occurs to the beam and whether the communication error occurs, when constraints (including times of the communication error calculated by both the base station and the user equipment with a timeout value, a value obtained by subtracting the initial value of the second timeout value of the user equipment from the initial value of the first timeout value of the base station is greater than 1, the communication errors of the base station only includes not-receiving uplink signal /channel transmitted by the user equipment, etc. ) in these examples has been satisfied. The beam to which a beam failure occurs carries downlink control channel when the trigger condition is continuous communication error (referring to FIG. 9 and related description thereof) . The beam to which a beam failure occurs carries an uplink channel when the trigger conditions are the beam failure message and that the communication error occurs (referring to FIG. 10 and related description thereof) . The beam to which a beam failure occurs carries PDSCH when the trigger conditions are the beam failure message and that the communication error doesn’t occur (referring to FIG. 11 and related description thereof) . Of course, the base station may also decide the beam to which a beam failure occurs according to the beam failure message, for example, the base station determines a failure channel according to failure type thereof, and then determines that a beam failure occurs to the beam.

When there is more than one beam to which a beam failure occurs, the base station /user equipment may not be able to directly figure out all the beams to which a beam failure occurs, but gradually figure out beams to which a beam failure occurs via the cycle "determining-switching" . In general, the beam to which a beam failure occurs, which are automatically determined by oneself without assistance of the other, may be figured out preferentially. For example, when a beam failure occurs to both beams carrying downlink control channel and PDSCH respectively, the base station will decide that a beam failure occurs to the beam carrying downlink control channel as the base station fails to receive any uplink signals /channels, and the base station decides that a beam failure occurs to the beam carrying PDSCH only after transmitting downlink control channel via the backup beam.

When the constraints varies, determining criterion, with which the base station /user equipment decides what type of signal /channel carried in the beam to which a beam failure occurs, will varies correspondingly, depending upon specific constraints. In one example, the difference between the initial value of the first timeout value and the initial value of the first timeout value, in the constraints of the above examples, varies from being greater than 1 to being less than or equal to 1, meaning that the base station may probably receive the beam failure message after deciding that the beam failure occurs to the beam according the number of the times that the communication error occurs continuously. In other words, the channel carried in the beam to which a beam failure occurs may be downlink control channel and /or uplink channel when the trigger condition is the continuous communication error. In another example, the communication errors of the base station may further include receiving NACK. At this time, the channel carried in the beam to which a beam failure occurs is PDSCH when the trigger condition is that continuous communication errors mean receiving the NACK.

Referring to FIG. 12, a beam-based communication method according to a ninth embodiment is based on the beam-based communication method according to the first embodiment. As shown in FIG. 12, the beam-based communication method may further include the following block between blocks S12 and S13.

In block S16, the base station may select the backup beam according information of a candidate beam pool.

The base station may select at least one candidate beam thereof as the backup beams according to information of a candidate beam pool. Therefore, the backup beams belong to the candidate beam pool. The selected backup beams may be used for replacing uplink default beams and /or downlink default beams. And the selected backup beams may be removed from the candidate beam pool or marked as being unavailable. If there are not any available candidate beams, the base station /user equipment may fail to switch to the candidate beams, leading to a beam link failure.

The candidate beam pool may include at least one uplink candidate beam and at least one downlink candidate beam. And each default beam may be corresponding to at least one candidate beam. Uplink /downlink candidate beams corresponding to different uplink /downlink default beams may be same, and also different.

If uplink /downlink data and control signalings may be carried in different uplink /downlink default beams, the number of the default beams used for carrying control signalings and corresponding to the candidate beams may be greater than that of the default beams used for carrying data. Thus, the beam link failure may be prevented during the control signaling transmission.

If the number of the candidate beams corresponding to one default beam is greater than one, time-frequency domain resource occupied by different candidate beams may be same. Thus, the overhead of the base station /user equipment may be reduced.

In the case of the beam to which a beam failure occurs, compared with re-training beam to decide the backup beams, selecting the backup beams from the candidate beam pool in present embodiment may omit a beam training procedure, effectively shortening delay and reducing signaling overhead. The method in the present embodiment may be combined with that in any one embodiment of the above embodiments.

When the method in present embodiment may be combined with that in the eighth embodiment, in order to reduce resource consumption, the base station may only select candidate beams for default beams to which a beam failure occurs.

In one embodiment, the candidate beam pool may include at least one candidate beam of each channel. The candidate beam of each channel and a default beam thereof belong to different transceiving nodes, or correlation between the candidate beam and the default beam is less than or equal to a preset threshold. Channels may include one or a multiple physical channels. The transceiving node may be distributed unit (DU) , transmission point (TP) , transmission reception point (TRP) or Radio Remote Head (RRH) in CU (Central Unit) /DU structure or other similar structures.

The correlation may be used for evaluating the degree of association between two beams. In general, higher coverage overlap rate, and stronger the mutual interference, then higher the correlation. A beam, belonging to a same transceiving node with the default beams or having high correlation therebetween (meaning the correlation is greater than the preset threshold) will probably also be blocked or have bad beam performance, in case that a beam failure occurs in the default beam between the base station and the user equipment. The default beams and candidate beams thereof belong to different transceiving nodes or have low correlation (meaning the correlation is less than or equal to the preset threshold) , reducing the possibility switching to the backup beams with a beam failure or bad performance. Thus the system performance may be improved.

Referring to FIG. 13, a beam-based communication method according to a tenth embodiment is based on the beam-based communication method according to the ninth embodiment. As shown in FIG. 13, the beam-based communication method may further include the following block before the block S16.

In block S17, the base station may transmit information of the candidate beam pool to the user equipment.

In this way, the user equipment may automatically select the backup beams from the candidate beams when uplink default beams are required to be switched, which has higher activeness and shorter delay, and is suitable for the situation where a beam failure occurs to beams respectively carrying PUCCH and PUSCH, compared with the switching with the instructions of the base station.

The block S17 may be executed periodically or non-periodically. The periodic trigger conditions may include that the candidate beam pool varies, for example, the candidate beam pool may be re-constructed when candidate beams thereof are selected as the backup beams.

The executed sequence of the block S17 and other blocks before block S16 in the above embodiment is not restrictive. The block S17 may be executed periodically or non-periodically. The periodic trigger conditions may include that the candidate beam pool varies and /or the base station begins to communicate with the user equipment.

Referring to FIG. 14, a beam-based communication method according to an eleventh embodiment is based on the beam-based communication method according to the ninth embodiment. As shown in FIG. 14, the beam-based communication method may further include the following blocks before the block S16.

In block S191, the base station may transmit a plurality of training beams to the user equipment.

In block S192, the user equipment may measure the training beams to acquire measurement results.

The measurement results may include performance indexes of each training beam, such as Reference Signal Receiving Power (RSRP) , Reference Signal Receiving Quality (RSRQ) and so on.

In block S193, the user equipment may transmit the measurement results to the base station.

In block S194, the base station may determine the candidate beam pool according to the measurement results.

The base station may select a specified number of training beams with optimal beam performance as candidate beams to put into the candidate beam pool from all the training beams according to performance indexes of beams in the measurement results.

In one embodiment, the training beams may be divided into at least two groups, the training beams in each group belong to a same transceiving node, or correlation therebetween may be greater than or equal to a preset threshold. The training beams of the same group have a greater probability to be blocked at the same time. At this time, the base station may select a beam-training group, of which beam performance index is greater than or equal to a third threshold in the measurement results, as a backup beam-training group from all beam-training groups. And then the base station may select a specified number of training beams with optimal beam performance as candidate beams to put into the candidate beam pool from the backup beam-training group, or select a specified number of training beams with optimal beam performance in the measurement results as candidate beams to put into the candidate beam pool from all the beam-training groups.

A procedure to construct the candidate beam pool for the user equipment is provided in present embodiment. The procedure may be executed periodically or non-periodically. Periodic trigger conditions may include that wireless environment varies (such as the distance /speed the user equipment moves is greater than a threshold, the state of the switch of the transceiving node varies, beams of the transceiving node are adjusted, the weather varies, etc. ) and /or the base station begins to communicate with the user equipment.

The procedure to construct the candidate beam pool in this embodiment may also be used for selecting default beams. At this time, the base station may firstly select a part of candidate beams (with optimal performance generally) as the default beams, and then determine the candidate beam pool from the remaining training beams.

Referring to FIG. 15, the execution subject of a beam-based communication method in accordance with a twelfth embodiment may be a user equipment. The user equipment may be fixed and also mobile, such as cellular phones, personal digital assistants (PDA) , wireless modems, tablet PCs, laptops, cordless phones, etc. As shown in FIG. 15, the beam-based communication method may include the following blocks in this embodiment.

In block S21, the user equipment communicates with a base station via a beam.

Initially-used beams are default beams. The default beams may include at least one uplink default beam and at least one downlink default beam. The uplink default beam is configured for transmitting data and control signalings to the base station by the user equipment in a default state. The downlink default beam is configured for transmitting data and control signalings to the user equipment by the base station in the default state. The user equipment may transmit an uplink signal /channel to the base station via the uplink default beam, and /or receive a downlink signal /channel transmitted by the base station via the downlink default beam.

Narrower coverage of a beam, more easily a beam failure happens. In one embodiment, Uplink /downlink data and control signalings may be respectively carried in different uplink /downlink default beams, and the coverage of the beam carrying control signalings is greater than that of the beam carrying data. In this way, the possibility that causes a control signaling transmission error shall be reduced.

In block S22, the user equipment may determine whether a beam failure occurs to the beam.

The trigger conditions to decide that a beam failure occurs to a beam may include at least one of the following: the number of times that a communication error occurs continuously is greater than or equal to a first preset threshold, duration in which the communication error occurs continuously is greater than or equal to a second preset threshold, and a beam-switching instruction transmitted by the base station is received. In addition, the trigger condition to decide that a beam failure occurs to the beam may further include that beam performance is lower than a preset value, and /or a beam link failure occurs.

The beam to which a beam failure occurs may be one or more uplink /downlink default beams. The user equipment may respectively determine each uplink /downlink default beam, when the number of uplink /downlink default beams is greater than one. The user equipment may also determine at least two uplink /downlink default beams together, such as all uplink /downlink default beams.

Channels carried in the beam to which a beam failure occurs may include at least one of a PDCCH, a PHICH, a PDSCH, a PUCCH and a PUSCH.

Block S23 may be executed when the beam failure occurs to the beam, the subsequent communication via the default beam may be continued when a beam failure doesn’t occur to the beam.

In block S23, the user equipment may communicate with the user equipment via a backup beam when the beam failure occurs to the beam.

The backup beams may be used to replace a part of default beams (at least including beam to which a beam failure occurs) or all the default beams. And the backup beams may be different from the replaced default beams. The performances of the backup beams may support normal use or are superior to that of the replaced default beams.

Which uplink /downlink default beams to which a beam failure occurs may be further identified and only beam to which a beam failure occurs may be replaced, when the number of the uplink /downlink default beams is greater than one, and candidate beams (to which the base station may switch) for different uplink /downlink default beams are different. In this way, resource consumption caused by the switching may be reduced.

The base station and/or the user equipment will need to switch to backup beams from the replaced default beams. The switching process may be performed independently by the base station or the user equipment, and also be performed with assistance or indication of the other one.

With the implementation of the above embodiment, the backup beams may be adopted for communication in the situation that a beam failure occurs to the beams via which the user equipment communicates with the base station is decided. When a sudden beam failure happens and continues, compared with the directly re-initiating random access in the prior art, communication via the backup beams may avoid the beam link failure and the subsequent random access caused as the beam to which a beam failure occurs are continuously used, and may reduce latency. Compared with the multi-beam transmission in the prior art, the backup beams are only adopted in case that the beam failure occurs to the beams, effectively reducing the occupation of spatial domain resource and improving transmission performance. Thus the transmission performance and robustness against beam failure may be considered simultaneously, and a beam-based communication with robustness against beam failure may be achieved with high performance and low delay.

Referring to FIG. 16, a beam-based communication method according to a thirteenth embodiment is based on the beam-based communication method according to the twelfth embodiment. Whether the beam failure occurs to the beam is determined according to the number of times and /or duration in which a communication error occurs continuously. The beam-based communication method in the thirteenth embodiment is further extended based on the twelfth embodiment of the present disclosure, thus the same details with that in the twelfth embodiment will not be described again herein. As shown in FIG. 16, the beam-based communication method in the thirteenth embodiment may include the following blocks.

In block S211, the user equipment may receive a downlink signal /channel transmitted by the base station via a first beam.

The downlink signal /channel may be configured for transmitting downlink data and /or control signalings. The first beam may be one downlink default beam.

In block S212, the user equipment may determine whether a communication error occurs.

The communication error may include receiving NACK used for indicating failure of uplink transmission (such as PUSCH) , receiving the re-transmitted downlink signal /channel, and receiving control signaling (which may be carried in PDCCH) used for indicating uplink re-transmission (including uplink data and /or control signalings) . At this time, the beam carrying the PUCCH/PUSCH may probably be blocked, which has been described in details accompanying with FIG. 10. The communication may also include not-receiving downlink signal /channel transmitted by the base station during a preset time, and at this time the user equipment may probably directly perform uplink transmission in case that the user equipment does not have uplink grant, and the beam carrying the PUCCH/PUSCH may be blocked.

Downlink signals /channels being transmitted successfully may include the PDCCH. The communication error may include not-receiving downlink data carried in PDCCH and corresponding to DCI, which has been described in details accompanying with FIG. 11.

Block S213 may be executed when the communication error occurs, otherwise the subsequent communication with the base station via the default beam may be continued, and a timeout value may further be initialized when the timeout value may be adopted to calculate the number of the times that the communication error occurs continuously.

In block S213, the user equipment may determine whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or the duration in which the communication error occurs continuously is greater than or equal to the second preset threshold.

The user equipment may distinguish different types of communication errors in calculating the number of the times /duration, that is to say, the user equipment respectively calculates the number of the times /duration of each type of the communication error, and may also not distinguish different types of communication errors, if there is not just one type of the communication error.

The user equipment may calculate the number of the times /duration that the communication error occurs continuously with a timeout value, which has been described in details in the beam-based communication methods in accordance with the fifth and sixth embodiment of the present disclosure, and will not be described herein.

The user equipment may initialize a timer to start timing when the communication error occurs firstly. In the subsequent process, the user equipment may stop timing and reset the timer with the initial value when the communication error doesn’t occur, and continue to time and calculate the difference between the current value of the number of the timer and the initial value as the duration when the communication error occurs. The user equipment may also calculate the difference between the last moment and the first moment when the communication error occurs continuously as the duration.

Block S214 may be executed when the times is greater than the first preset threshold and /or the duration is greater than the second preset threshold, otherwise the block S211 may be executed to repeat the above process. The user equipment may execute corresponding operations according to the type of the communication error, before the block S211 may be executed.

If the communication error may include at least one of receiving NACK used for indicating uplink transmission failure, receiving the re-transmitted downlink signal /channel, receiving control signaling used for indicating uplink re-transmission, and not-receiving down signal /channel transmitted by the base station within a preset time period, there meaning that PUCCH/PUSCH is probably blocked, then corresponding operations may include re-transmitting uplink signal /channel. If the communication error may include not-receiving downlink data corresponding to downlink control message, there meaning that PDSCH is probably blocked, then corresponding operations may include transmitting NACK to the base station.

In block S214, the user equipment may decide that the beam failure occurs to the beam.

In block S215, the user equipment may transmit the uplink signal /channel to the base station via the backup beam, and /or receive a downlink signal /channel transmitted by the base station via the backup beam.

Referring to FIG. 17, a beam-based communication method according to a fourteenth embodiment is based on the beam-based communication method according to the twelfth embodiment. Whether the beam failure occurs to the beam is determined according to the whether a beam failure message is received and the number of times and /or duration in which a communication error occurs continuously. Compared with that in the thirteenth embodiment, the beam-based communication method in the fourteenth embodiment has a difference which is that determining whether a beam-switching instruction is received is added. The same details with that in the thirteenth embodiment will not be described again herein. As shown in FIG. 17, the beam-based communication method in the fourteenth embodiment may include the following blocks.

In block S221, the user equipment may receive a downlink signal /channel transmitted by the base station via a first beam.

In block S222, the user equipment may determine whether the downlink signal /channel carries a beam-switching instruction.

Block S225 may be executed when the downlink signal /channel carries the beam-switching instruction, otherwise block S223 may be executed.

In block S223, the user equipment may determine whether a communication error occurs.

Block S224 may be executed when the communication error occurs, otherwise the subsequent communication with the base station via the default beam may be continued and a timeout value may further be initialized when the timeout value may be adopted to calculate the number of the times that the communication error occurs continuously.

In block S224, the user equipment may determine whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or the duration in which the communication error occurs continuously is greater than or equal to the second preset threshold.

Block S225 may be executed when the number of the times is greater than the first preset threshold and /or the duration is greater than the second preset threshold, otherwise the block S221 may be executed to repeat the above process. The user equipment may execute corresponding operations according to the type of the communication error before the block S221 may be executed.

In block S225, the user equipment may determine that the beam failure occurs to the beam.

In block S226, the user equipment may transmit an uplink signal /channel to the base station via the backup beam, and /or receive a downlink signal /channel transmitted by the base station via the backup beam.

Referring to FIG. 18, a beam-based communication method according to a fifteenth embodiment is based on the beam-based communication method according to the twelfth embodiment. Whether the beam failure occurs to the beam is determined according to whether a beam failure message is received and times and /or duration that a communication error occurs continuously. Compared with that in the fourteenth embodiment, the beam-based communication method in the fifteenth embodiment has a difference which is that firstly-determining whether the communication error occurs and secondly-determining whether the beam failure message is received. The same details with that in the fourteenth embodiment will not be described again herein. As shown in FIG. 18, the beam-based communication method in the fifteenth embodiment may include the following blocks.

In block S231, the user equipment may receive a downlink signal /channel transmitted by the base station via a first beam.

In block S232, the user equipment may determine whether a communication error occurs.

Block S233 may be executed when the communication error occurs, otherwise block S234 may be executed and a timeout value may further be initialized when the timeout value may be adopted to calculate the number of the times that the communication error occurs continuously.

In block S233, the user equipment may determine whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or the duration in which the communication error occurs continuously is greater than or equal to the second preset threshold.

Block S235 may be executed when the number of the times is greater than or equal to the first preset threshold and /or the duration is greater than equal to the second preset threshold, otherwise the block S231 may be executed to repeat the above process. The user equipment may execute corresponding operations according to the type of the communication error before the block S231 may be executed.

In block S234, the user equipment may determine whether the downlink signal /channel carries a beam-switching instruction.

Block S235 may be executed when the downlink signal /channel carries the beam-switching instruction, otherwise the user equipment continues to communicate with the base station via the default beams.

In block S235, the user equipment may determine that the beam failure occurs to the beam.

In block S236, the user equipment may transmit an uplink signal /channel to the base station via the backup beam, and /or receive a downlink signal /channel transmitted by the base station via the backup beam.

In the beam-based communication methods of the fourteenth and fifteenth embodiment of the present disclosure, the process to determine whether a beam failure message is received and the process to determine whether the communication error occurs are independent, while in some embodiment, the base station may simultaneously perform those both determining processes.

Referring to FIG. 19, a beam-based communication method according to a sixteenth embodiment is based on the beam-based communication method according to the twelfth embodiment. As shown in FIG. 19, the beam-based communication method may further include the following block between blocks S22 and S23.

In block S24, the user equipment may determine what signals /channels carried in the beam to which a beam failure occurs according to the type of the communication error or the received beam-switching instruction.

In present embodiment, the number of uplink default beams and /or the number of down default beams are /is greater than one, and different default beams may carry different signals /channels. The user equipment may determine failure signals /channels and then determine the beam to which a beam failure occurs, so as to conveniently select the backup beam in subsequent process. The method in the sixteenth embodiment may be combined with that in any one of the above embodiments. In one embodiment, the block S24 may be executed at the same time the block S22 may be executed, that is to say, the user equipment may identify which beam failure occurs to the beam at same time as determining that the beam failure occurs to the beam.

Still referring to FIGs. 9-11 and examples thereof, the user equipment can determine what signal /channel carried in the beam to which a beam failure occurs according to type of the communication error, when constraints (including times of the communication error calculated by both the base station and the user equipment with a timeout value, a value obtained by subtracting the initial value of the second timeout value of the user equipment from the initial value of the first timeout value of the base station is greater than 1, the communication errors of the base station only includes not-receiving uplink signal /channel transmitted by the user equipment, etc. ) in these examples has been satisfied. The communication errors may include receiving NACK used for indicating failure of uplink transmission (PUSCH) , receiving the re-transmitted downlink signal /channel, and receiving control signaling used for indicating uplink re-transmission (including uplink data and /or control signalings) (referring to FIG. 10 and description thereof) , and not-receiving downlink signal /channel transmitted by the base station during the preset time (directly performing uplink transmission in case that the user equipment does not have uplink grant) , which means that the beam to which a beam failure occurs carries uplink channel. The user equipment may identify which uplink channel carried in the beam to which a beam failure occurs according to the used channel when performing last uplink transmission. The communication error may include not-receiving downlink data corresponding to DCI, which means that the beam to which a beam failure occurs carries PDSCH (referring to FIG. 11 and description thereof) . When receiving a beam-switching instruction, the user equipment may also decide the beam to which a beam failure occurs according to the beam-switching instruction. For example, a failure channel may be determined according to failure type thereof, and then the beam to which a beam failure occurs may be determined.

Referring to FIG. 20, a beam-based communication method according to a seventeenth embodiment is based on the beam-based communication method according to the twelfth embodiment. As shown in FIG. 20, the beam-based communication method may further include the following block after the block S22.

In block S25, the user equipment may transmit a beam-switching message to the base station when the beam failure occurs to the beam.

The beam-switching message may be configured for assisting the base station to switch to the backup beam from downlink default beams to transmit the downlink signal /channel. The beam-switching message may include failure type and /or information of the backup beam. The failure type may be configured for indicating signal /channel carried in the beam to which a beam failure occurs. The beam carrying the beam-switching message may be a default beam or a backup beam. The executed sequence of blocks S25 and S23 is not restrictive. For example, the user equipment may transmit uplink signal /channel at same time as transmitting the beam-switching message to the base station via the backup beam. The beam-based communication method in seventeenth embodiment may be combined with that in any one of the above embodiments.

Referring to FIG. 21, a beam-based communication method according to an eighteenth embodiment is based on the beam-based communication method according to the twelfth embodiment. As shown in FIG. 21, the beam-based communication method may further include the following block between blocks S12 and S13.

In block S26, the user equipment may select the backup beam according information of a candidate beam pool.

The user equipment may select at least one candidate beam thereof as the backup beams according the information of the candidate beam pool. Therefore, the backup beams belong to the candidate beam pool. The selected backup beams may be used for replacing uplink default beams and /or downlink default beams. And the selected backup beams may be removed from the candidate beam pool or marked as being unavailable. If there are not any available candidate beams, the base station /user equipment may fail to switch to the candidate beams, leading to a beam link failure.

In the case of the beam to which a beam failure occurs, compared with re-training beam to determine the backup beams, selecting the backup beams from the candidate beam pool in present embodiment may omit a beam training procedure, effectively shortening delay and reducing signaling overhead. The beam-based communication method in the present embodiment may be combined with that in any one of the above embodiments.

When the beam-based communication method in the present embodiment may be combined with that in the sixteenth embodiment, in order to reduce resource consumption, the base station may select candidate beams only for default beams to which a beam failure occurs.

In one embodiment, the candidate beam pool may include at least one candidate beam of each channel. The candidate beam of each channel and a default beam thereof belong to different transceiving nodes, or correlation between the candidate beam and the default beam is less than or equal to a preset threshold, reducing the possibility switching to the backup beams with a beam failure or bad performance. Thus the system performance may be improved. Channels may include one or multiple physical channels.

Referring to FIG. 22, a beam-based communication method according to a nineteenth embodiment is based on the beam-based communication method according to the seventeenth embodiment. As shown in FIG. 22, the beam-based communication method may further include the following block before the block S26.

In block S27, the user equipment may receive the information of the candidate beam pool from the base station.

In this way, the user equipment may automatically select the backup beams from the candidate beam pool when uplink default beams are required to be switched, which has higher activeness and shorter delay, and is suitable for the situation where a beam failure occurs to both beams respectively carrying PUCCH and PUSCH, compared with the switching with the instructions of the base station.

Before the block S27, the base station may construct the candidate beam pool for the user equipment, which has been described in the beam-based communication method in accordance with the eleventh embodiment of the present disclosure, and will not be described herein.

Referring to FIG. 23, a beam-based communication apparatus according to a first embodiment may include a processor 110 and a communication circuit 120. The processor 110 may be connected to the communication circuit 120.

The communication circuit 120 may be configured for transmitting and receiving data, which is an interface for communication between the beam-based communication apparatus and other communication devices.

The processor 110 may be configured for performing programs to achieve any one of the beam-based communication methods in accordance with the first to eleventh embodiment or a method provided with arbitrary and non-conflicting combination of the beam-based communication methods therein.

The beam-based communication apparatus in the present embodiment may be a base station, and also be a separate component integrated in a base station, such as a base band board.

Referring to FIG. 24, a beam-based communication apparatus according to a second embodiment may include a processor 210 and a communication circuit 220. The processor 210 may be connected to the communication circuit 220.

The communication circuit 220 may be configured for transmitting and receiving data, which is an interface for communication between the beam-based communication apparatus and other communication devices.

The processor 210 may be configured for performing programs to achieve any one of the beam-based communication methods in accordance with the twelfth to nineteenth embodiment or a method provided with arbitrary and non-conflicting combination of the beam-based communication methods therein.

The beam-based communication apparatus in the present embodiment may be a user equipment, and also be a separate component integrated in a user equipment, such as a base band chip.

Referring to FIG. 25, a beam-based communication apparatus according to a third embodiment may include a memory 310. The memory 310 is used to store instructions therein. When the instructions is performed, any one of the beam-based communication methods in accordance with the first to eleventh embodiment or a method provided with arbitrary and non-conflicting combination of the beam-based communication methods therein may be achieved. The memory 310 may include a Read-Only Memory (ROM) , a Random Access Memory (RAM) , a Flash Memory, hard disk, optical disk, etc.

The functions of each part of each beam-based communication apparatus and the feasible expansion can be referred to the description of the corresponding beam-based communication method according to embodiments of the present disclosure, and be no longer repeated to describe herein.

The above description depicts merely some exemplary embodiments of the disclosure, but is meant to limit the scope of the disclosure. Any equivalent structure or flow transformations made to the disclosure, or any direct or indirect applications of the disclosure on other related fields, shall all be covered within the protection of the disclosure.

Claims

A beam-based communication method, comprising:

communicating with a user equipment via a beam；

determining whether a beam failure occurs to the beam； and

communicating with the user equipment via a backup beam when the beam failure occurs to the beam.
The method of claim 1, wherein the communicating with the user equipment via the beam comprises:

transmitting a downlink signal /channel to the user equipment via a first beam, and /or receiving a uplink signal /channel transmitted by the user equipment via a second beam； and

the beam failure occurring to the beam comprises at least one of the following:

the number of times that a communication error occurs continuously is greater than or equal to a first threshold, a duration in which the communication error occurs continuously is greater than or equal to a second threshold, and a beam failure message is received from the user equipment.
The method of claim 2, wherein the determining whether the beam failure occurs to the beam comprises:

determining whether the beam failure message is received from the user equipment；

determining that the beam failure occurs to the beam when the beam failure message is received from the user equipment, and determining whether the communication error occurs when no beam failure message is received from the user equipment；

determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold and /or duration in which the communication error occurs continuously is greater than or equal to the second threshold, when the communication error occurs； and

determining that the beam failure occurs to the beam when the number of the times greater than or equal to the first threshold and /or the duration is greater than or equal to the second threshold, and otherwise, continuing to re-transmit the downlink signal /channel via the first beam and then repeat the above process.
The method of claim 2, wherein the determining whether the beam failure occurs to the beam comprises:

determining whether the communication error occurs；

determining whether the beam failure message from the user equipment is received when no communication error occurs, and determining that the beam failure occurs to the beam when the beam failure message is received； and

determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold and /or duration in which the communication error occurs continuously is greater than or equal to the second threshold when the communication error occurs, and determining that the beam failure occurs to the beam when the number of the times is greater than or equal to the first threshold and /or the duration is greater than or equal to the second threshold, and otherwise, re-transmitting the downlink signal /channel via the first beam and then repeating the above process.
The method of claim 2, wherein the determining whether the beam failure occurs to the beam comprises:

determining whether the communication error occurs；

determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold and /or the duration in which the communication error occurs continuously is greater than or equal to the second threshold, when the communication error occurs； and

determining that the beam failure occurs to the beam when the times is greater than or equal to the first threshold and /or the duration is greater than or equal to the second threshold, and otherwise re-transmitting the downlink signal /channel via the first beam and then repeating the above process.
The method of claim 3, wherein the determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold comprises:

incrementing a timeout value by one, wherein the timeout value has an initial value as 0 and the timeout value remains the initial value when the communication error doesn’t occur；

judging whether the timeout value is greater than or equal to the first threshold； and

deciding that the number of the times is greater than or equal to the first threshold when the timeout value is greater than or equal to the first threshold.
The method of claim 3, wherein the determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first threshold comprises:

decrementing a timeout value by one, wherein the timeout value has an initial value as the first threshold and the timeout value remains the initial value when the communication error doesn’t occur；

judging whether the timeout value is greater than or equal to 0； and

deciding that the number of the times is greater than or equal to the first threshold when the timeout value is greater than or equal to 0.
The method of claim 2, wherein the communication error comprises not-receiving the uplink signal /channel transmitted by the user equipment within a preset time period, and /or receiving a negative acknowledgement transmitted by the user equipment in response to the downlink signal /channel.
The method of claim 2, wherein beams monitored by the base station when determining whether the beam failure message from the user equipment is received and /or whether the communication error occurs comprise the second beam and candidate beams corresponding to the second beam.
The method of claim 2, wherein the method further comprises the following step after the determining that whether the beam failure occurs to the beam:

determining what signals /channels carried in the beam to which a beam failure occurs according to at least one of the following: a trigger condition to determine that the beam failure occurs to the beam, whether a communication error occurs, the received beam failure message and types of the communication error.
The method of claim 2, wherein the first threshold is greater than a threshold of the number of the times that the communication error occurs continuously used when the user equipment determines whether the beam failure occurs to the beam, and the second threshold is greater than a threshold of the duration in which the communication error occurs continuously used when the user equipment determines whether the beam failure occurs to the beam.
The method of claim 1, wherein channels carried in the beam to which a beam failure occurs comprise at least one of a physical downlink control channel, a physical hybrid-ARQ indicator channel, a physical downlink shared channel, a physical uplink control channel and a physical uplink shared channel.
The method of claim 1, wherein the communicating with the user equipment via the backup beam comprises:

transmitting a downlink signal /channel to the user equipment via the backup beam, and /or receiving an uplink signal /channel transmitted by the user equipment via the backup beam.
The method of claim 1, wherein the method further comprises the following step after the determining that whether the beam failure occurs to the beam:

transmitting a beam-switching instruction to the user equipment when the beam failure occurs to the beam, wherein the beam-switching instruction comprises a failure type and /or information of the backup beam, and the failure type is configured for indicating what a signal /channel carried in the beam to which a beam failure occurs.
The method of claim 1, wherein the method further comprises the following step before communicating with the user equipment via the backup beam:

selecting the backup beam according to information of a candidate beam pool, wherein the backup beam belongs to the candidate beam pool.
The method of claim 15, wherein the candidate beam pool comprises at least one candidate beam of each channel.
The method of claim 16, wherein the candidate beam and a default beam of each channel belong to different transceiving nodes, or correlation between the candidate beam and the default beam is less than or equal to a preset threshold.
The method of claim 15, wherein the method further comprises the following step before the selecting the backup beam according to the information of the candidate beam pool:

transmitting the information of the candidate beam pool to the user equipment.
The method of claim 15, wherein the method further comprises the following step before the selecting the backup beam according to the information of the candidate beam pool:

transmitting a plurality of training beams to the user equipment, thereby measuring the training beams by the user equipment to acquire measurement results；

receiving the measurement results from the user equipment； and

determining the candidate beam pool according to the measurement results.
The method of claim 19, wherein the training beams are divided into at least two groups, in each of which the training beams belong to a same transceiving node, or correlation therebetween is greater than or equal to a preset threshold；

determining the backup beam according to the measurement results comprises:

selecting a beam-training group from all the beam-training groups as a backup beam-training group, of which beam performance is greater than or equal to a third threshold in the measurement results, and selecting a specified number of training beams with optimal beam performance as candidate beams to put into the candidate beam pool from the backup beam-training group； or

selecting a specified number of training beams with optimal beam performance in the measurement results as candidate beams to put into the candidate beam pool from all beam-training groups； or

respectively selecting a specified number of training beams with optimal beam performance in the measurement results as candidate beams to put into the candidate beam pool from each training beam group.
A beam-based communication method, comprising:

communicating with a base station via a beam；

determining whether a beam failure occurs to the beam； and

communicating with the user equipment via a backup beam when the beam failure occurs to the beam.
The method of claim 21, wherein the communicating with the base station via the beam comprises:

receiving a downlink signal /channel to transmitted by the base station via a first beam, and/or transmitting a uplink signal /channel via a second beam； and

the beam failure occurring to the beam comprises at least one of the following:

the number of times that a communication error occurs continuously is greater than or equal to a first preset threshold, a duration in which the communication error occurs continuously is greater than or equal to a second preset threshold, and a beam-switching instruction transmitted by the base station is received.
The method of claim 22, wherein the determining whether the beam failure occurs to the beam comprises:

determining whether the communication error occurs；

determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or duration in which the communication error occurs continuously is greater than or equal to the second preset threshold when the communication error occurs； and

determining that the beam failure occurs to the beam when the number of the times is greater than or equal to the first preset threshold and/or the duration is greater than or equal to the second preset threshold.
The method of claim 22, wherein the determining whether the beam failure occurs to the beam comprises:

determining whether the downlink signal /channel carries the beam-switching instruction；

determining that the beam failure occurs to the beam when the downlink signal /channel carries the beam-switching instruction, and otherwise determining whether the communication error occurs；

determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or duration in which the communication error occurs continuously is greater than or equal to the second preset threshold when the communication error occurs； and

determining that the beam failure occurs to the beam when the number of the times is greater than or equal to the first preset threshold and/or the duration is greater than or equal to the second preset threshold.
The method of claim 22, wherein the determining whether the beam failure occurs to the beam comprises:

determining whether the communication error occurs；

determining whether the downlink signal /channel carries the beam-switching instruction when no communication errors occur, and determining that the beam failure occurs to the beam when the downlink signal /channel carries the beam-switching instruction； and

determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or duration in which the communication error occurs continuously is greater than or equal to the second preset threshold when the communication error occurs, and determining that the beam failure occurs to the beam when the number of the times is greater than or equal to the first preset threshold and/or the duration is greater than or equal to the second preset threshold.
The method of claim 23, wherein the determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold comprises:

incrementing a timeout value by one, wherein the timeout value has an initial value as 0 and the timeout value remains the initial value when no communication errors occur；

judging whether the timeout value is greater than or equal to the first preset threshold； and

deciding that the number of the times is greater than or equal to the first preset threshold when the timeout value is greater than or equal to the first preset threshold.
The method of claim 23, wherein the determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold comprises:

decrementing a timeout value by one, wherein the timeout value has an initial value as the first preset threshold and the timeout value remains the initial value when the communication error doesn’t occur；

judging whether the timeout value is greater than or equal to 0； and

deciding that the number of the times is greater than or equal to the first preset threshold when the timeout value is greater than or equal to 0.
The method of claim 22, wherein the communication error comprises at least one of the following: receiving negative acknowledgment configured for indicating uplink transmission failure, receiving the re-transmitted downlink signal /channel, receiving a control signaling configured for indicating uplink re-transmission, not-receiving downlink signal /channel transmitted by the base station within a preset time period and not-receiving downlink data corresponding to downlink control message carried in the downlink signal /channel.
The method of claim 28, wherein the communication error comprises at least one of the following: receiving negative acknowledgment configured for indicating uplink transmission failure, receiving the re-transmitted downlink signal /channel, receiving a control signaling configured for indicating uplink re-transmission, and not-receiving downlink signal /channel transmitted by the base station within the preset time period； and

the method further comprises the following step after determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or duration in which the communication error occurs continuously is greater than or equal to the second preset threshold:

re-transmitting the uplink signal /channel when the number of the times is greater than or equal to the first preset threshold and /or the duration is greater than or equal to the second preset threshold.
The method of claim 28, wherein the communication error comprises not-receiving downlink data corresponding to downlink control message carried in the downlink signal /channel； and

the method further comprises the following step after determining whether the number of the times that the communication error occurs continuously is greater than or equal to the first preset threshold and /or duration in which the communication error occurs continuously is greater than or equal to the second preset threshold:

transmitting a negative acknowledgment to the base station when the number of the times is greater than or equal to the first preset threshold and /or the duration is greater than or equal to the second preset threshold.
The method of claim 30, wherein the method further comprises the following step after determining whether the beam failure occurs to the beam:

transmitting a beam failure message to the base station, wherein the beam failure message comprises failure types and/or information of the backup beam, the failure type is configured for indicating that channel carried in the beam to which a beam failure occurs is physical downlink shared channel, and the backup beam is configured for replacing a default beam carrying the physical downlink shared channel.
The method of claim 22, wherein the first preset threshold is smaller than a threshold of the number of the times that the communication error occurs continuously used when the base station determines whether the beam failure occurs to the beam.
The method of claim 22, wherein the method further comprises the following step after determining whether the beam failure occurs to the beam:

determining what signal /channel carried in the beam to which a beam failure occurs according to types of the communication error or the received beam-switching instruction.
The method of claim 21, wherein channels carried in the beam to which a beam failure occurs comprise at least one of a physical downlink control channel, a physical hybrid-ARQ indicator channel, a physical downlink shared channel, a physical uplink control channel and a physical uplink shared channel.
The method of claim 21, wherein the communicating with the base station via the backup beam comprises:

transmitting uplink signal /channel to the base station via the backup beam, and/or receiving downlink signal /channel transmitted by the base station via the backup beam.
The method of claim 21, wherein the method further comprises the following step after determining whether the beam failure occurs to the beam:

transmitting a beam failure message to the base station when the beam failure occurs to the beam, wherein the beam failure message comprises failure types and/or information of the backup beam, and the failure types are configured for indicating what signals /channels carried in the beam to which a beam failure occurs.
The method of claim 21, wherein the method further comprises the following step before communicating with the base station via the backup beam:

selecting the backup beam according to information of a candidate beam pool, wherein the backup beam belongs to the candidate beam pool.
The method of claim 37, wherein the method further comprises the following step before selecting the backup beam according information of a candidate beam pool：

receiving the information of the candidate beam pool from the base station.
The method of claim 38, wherein the candidate beam pool comprises at least one candidate beam of each channel.
The method of claim 39, wherein the candidate beam and a default beam of each channel belong to different transceiving nodes, or correlation between the candidate beam and the default beam is less than or equal to a preset threshold.
The method of claim 38, wherein the method further comprises the following step before receiving the information of the candidate beam pool from the base station:

measuring a plurality of training beams from the base station, thereby acquiring measurement results； and

transmitting the measurement results to the base station such that the base station determines the candidate beam pool according to the measurement results.
A beam-based communication apparatus, comprising a processor and a communication circuit, wherein the processor is connected to the communication circuit, and the processor is configured for executing programs to perform any one method in claims 1-20 or the method in claims 21-41.