CN110754050A

CN110754050A - Method and system for evaluating radio channel quality in a multi-beam communication scenario

Info

Publication number: CN110754050A
Application number: CN201780092199.7A
Authority: CN
Inventors: 郝鹏
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2017-06-16
Filing date: 2017-06-16
Publication date: 2020-02-04
Anticipated expiration: 2037-06-16
Also published as: WO2018227577A1; CN110754050B

Abstract

A method and system for assessing radio channel quality involves receiving a first reference signal of a first beam link; measuring a radio channel of the first beam link during a first portion of a radio link evaluation period using the first reference signal; receiving a second reference signal of a second beam link; measuring a radio channel of the second beam link during a second portion of the radio link evaluation period using the second reference signal; and evaluating the radio channel quality during a radio link evaluation period based on the measurement result of the radio channel of the first beam link and the measurement result of the radio channel quality of the second beam link.

Description

Method and system for evaluating radio channel quality in a multi-beam communication scenario

Technical Field

The present disclosure relates generally to multi-beam wireless communications and, more particularly, to methods and systems for assessing radio channel quality in a multi-beam communication scenario.

Background

In current long term evolution ("LTE") systems, a UE measures a radio channel using cell-specific reference signals ("CRS") and then evaluates downlink radio link quality (e.g., generates SINR of the downlink radio link) for an evaluation period. CRS is a wideband and "always on" signal that is typically transmitted with a single beam direction. The UE will use the assessment of the radio link to assess the radio link quality, i.e. compare the assessment of the radio link with the thresholds Qout and Qin and indicate to the higher layers the in-sync ("IS") or out-of-sync ("OOS") status. If the predefined condition IS met, the higher layer will declare a radio link failure based on the IS or OSS indication. After declaring a radio link failure, an RRC reestablishment procedure will be triggered to recover the radio link. This process is referred to as radio link monitoring, where the system is allowed to identify those cases where the network cannot stay in contact with the UE through the PDCCH.

The so-called new radio ("NR") proposal (also known as 5G) introduces multi-beam operation to combat the larger path loss experienced due to the higher carrier frequency. For multi-beam operation, the beam failure recovery process was studied. Multi-beam failure recovery involves monitoring the beam pair link and facilitating fast radio link recovery when the beam in use is blocked. A beam-to-link ("BPL") failure occurs when the radio link quality of the associated control channel (e.g., NR-PDCCH) falls below a certain level. The radio link quality of the monitored BPL for a certain period of time should be evaluated by measuring the corresponding RS.

The beam failure recovery procedure will be much faster than the whole radio link failure recovery. This is because beam failure recovery is a physical layer mechanism. When there is a long-term problem with the radio link quality, the RRC layer makes an assertion of RLF, at which time the UE needs to re-establish the RRC connection. In other words, when the beam failure recovery mechanism fails or is missing (e.g., in the case of single beam operation), RLM/RLF will solve the problem of the radio link. However, it has been decided that NR systems will not implement CRS-like signals.

Drawings

While the appended claims set forth the features of the present technology with particularity, these technologies, together with their objects and advantages, may be better understood from the following detailed description taken in conjunction with the accompanying drawings of which:

fig. 1 is a diagram of a system in which various embodiments of the present disclosure are implemented.

FIG. 2 illustrates an example hardware architecture in accordance with one embodiment.

Figures 3-8 illustrate how a communication node evaluates radio channel quality in a multi-beam communication scenario, in accordance with various embodiments.

Detailed Description

Since NR systems are not expected to use CRS-like signals, the present disclosure is directed to a method and system for assessing radio channel quality between a first communication node and a second communication node during a radio link assessment period. In various embodiments, the disclosed methods and systems perform radio link monitoring by reusing reference signals that are already to be used for beam-to-link monitoring.

Table 1 lists various abbreviations used in this disclosure along with their expanded forms.

TABLE 1

Fig. 1 depicts a wireless communication system 100, which includes a wireless base station 102 and a UE 104. In one embodiment, the wireless communication system 100 has many components not depicted in fig. 1, including other base stations, other UEs, wireless infrastructure, wired infrastructure, and other devices typically found in wireless networks. An example implementation of base station 102 includes a gbb. Example implementations of a UE include any device capable of wireless communication, such as smart phones, tablets, laptops, and non-legacy devices (e.g., home appliances or other parts of the "internet of things"). The base station 102 and the UE 104 may sometimes be referred to herein as "communication nodes. Thus, a "communication node" encompasses both types of devices.

Fig. 2 illustrates the basic (computing device) hardware architecture found in both the base station 102 and the UE 104, according to one embodiment. The base station 102 and the UE 104 also have other components, some of which are common to both, and others of which are not. The hardware architecture depicted in fig. 2 includes logic 202, memory 204, transceiver 206, and one or more antennas, represented by antenna 208. Each of these elements are communicatively linked to each other via one or more data paths 210. Examples of data paths include wires, conductive paths on a microchip, and wireless connections. Measurements made by the communication node (e.g., measurements made by the UE at each measurement instance as described below) may be stored in memory 204 (e.g., in a data structure such as a table). Such measurements may include, for example, the strength of a signal (e.g., a reference signal) received from another communication node (e.g., the strength of an RS received by the UE from a base station), the strength of a signal measured by the remote communication node from the source communication node (e.g., the strength of a signal measured by the base station and reported back to the UE), and the BLER.

The term "logic circuit" as used herein means a circuit (a type of electronic hardware) designed to perform a complex function defined in terms of mathematical logic. Examples of logic circuitry include a microprocessor, controller, or application specific integrated circuit. When the present disclosure refers to a device performing an action, it should be understood that this may also mean that the logic circuitry actually integrated with the device performs the action.

Possible implementations of memory 204 include: a volatile data storage device; a non-volatile data storage device; an electronic memory; a magnetic memory; an optical memory; random access memory ("RAM"); a cache memory; and a hard disk drive.

The following description sometimes refers to base stations and UEs without particular reference to fig. 1. However, it should be understood that all methods described herein can be performed by the base station 102 and the UE 104, which are referenced in a generic manner merely for convenience. Additionally, for each process described, in one embodiment, the steps are performed in the order recited in the language. In other embodiments, the steps are performed in a different order.

To help illustrate various embodiments of the present disclosure, a general description of a radio link monitoring and beam failure recovery scheme used in one implementation of system 100 will now be described. However, other implementations are possible.

A communication node operating within system 100 performs RLM to determine, among other things, whether a radio link IS OOS or IS. An analogy is made using LTE, where this determination is based on a SINR-like metric (e.g., a hypothetical PDCCH BLER), which indicates whether the UE can receive the PDCCH. Reference signals that may be used to derive such SINR-like metrics include CSI-RS, DM-RS for NR-PDCCH in C-SS, DMRS for NR-PBCH, NR-SSs, RS for time/frequency tracking (if separate RS is defined for time/frequency tracking). Each reporting instance will indicate a single IS or OOS regardless of the number of available beams in the cell. The IS/OOS indication IS provided periodically, and may be provided aperiodically. The physical layer performs OOS/IS indication and RRC declares RLF. For the purpose of RLF, the IS/OOS indication should be an indication for each cell.

A beam failure event ("beam failure") is considered to have occurred when the beam pair link quality of the associated control channel drops sufficiently low (e.g., below a threshold, an associated timer expires). When a beam failure occurs, a mechanism for recovering from the beam failure is triggered. For connected nodes, the UE declares RLF when the timer expires due to DL OOS detection, random access procedure failure detection and RLC failure detection.

The beam failure recovery procedure performed by the UE according to various implementations may be summarized as follows: the UE identifies a beam failure, identifies a new candidate beam, transmits a beam failure recovery request (e.g., sends the request in a symbol containing the RACH), and monitors for a response from the base station to the recovery request.

According to various embodiments, the UE uses one or more of the following signals in order to determine whether there is a beam failure and to identify a new candidate beam: RS for beam management (e.g., periodic CSI-RS, if configured by the network; periodic CSI-RS and SS-block within the serving cell, if SS-block is also used in beam management)), RS for fine timing/frequency tracking, SS-block, DM-RS of PDCCH (including group-common PDCCH and/or UE-specific PDCCH), DMRS for PDSCH.

The beam failure recovery request sent by the UE comprises at least one of the following: (1) explicit/implicit information identifying the UE and information about the new base station TX beam (candidate beam), and (2) explicit/implicit information identifying the UE and whether a new candidate beam exists.

Various embodiments will now be described. Refer to fig. 3 to 8. In general, the techniques described in connection with fig. 3 and 5-8 relate to a method and system for evaluating radio channel quality between, for example, a first communication node and a second communication node, during a radio link evaluation period, the radio link evaluation period having at least a first portion and a second portion. These embodiments relate to a communication node (such as a UE) receiving a first reference signal (e.g. from a base station) for a first beam link; measuring a radio channel of the first beam link during a first portion of a radio link evaluation period using the first reference signal; receiving a second reference signal (e.g., from the same base station or another base station) for a second beam link; measuring a radio channel of the second beam link during a second portion of the radio link evaluation period using the second reference signal; and evaluating the radio channel quality during a radio link evaluation period based on the measurement result of the radio channel of the first beam link and the measurement result of the radio channel of the second beam link.

In one embodiment, the evaluating step is initiated only if an indication that the second beam link is available is received before the end of the radio link evaluation period, or an indication that the second beam link is available is received before a time at which the radio link evaluation is to be performed.

Referring again to fig. 3 and 5-8, another embodiment involves the communication node receiving a first reference signal of a first beam link; monitoring a quality of the first beam link using the first reference signal; receiving a second reference signal of a second beam link; monitoring the quality of the second beam link using the second reference signal; using the first reference signal to evaluate a radio channel quality during a first portion of a radio link evaluation period; using the second reference signal to evaluate the radio channel quality during a second portion of the radio link evaluation period; and evaluating the radio channel quality during the radio link evaluation period based on the evaluation of the radio channel quality during the first part of the radio link evaluation period and the evaluation of the radio channel quality during the second part of the radio link evaluation period.

In the implementations shown in fig. 3 and 5, according to one embodiment, the first reference signal is detected before the second reference signal, and the first portion ends when the second reference signal is detected. Also, in one embodiment, the first reference signal is detected before the second reference signal, and the second portion begins when the second reference signal is detected.

In the implementations shown in fig. 3 and 5-7, according to one embodiment, the communication node performs measurements of the radio channel of the first beam link during a first beam monitoring period and performs measurements of the radio channel of the second beam link during a second beam monitoring period. Further, the communication node determines that the first beam link or the second beam link has failed based on the measurement result of the radio channel of the first beam link or the measurement result of the radio channel of the second beam link; and setting an end of the first portion of the radio link evaluation period or the second portion of the radio link evaluation period to a beginning of a beam monitoring period during which the first beam link or the second beam link is determined to have failed.

In the implementations shown in fig. 3 and 5, according to one embodiment, the communication node performs measurements of the radio channel of the first beam link during a first beam monitoring period. Further, the communication node determines that the first beam link has failed based on the measurement result of the radio channel of the first beam link; and setting a start of the second portion of the radio link evaluation period to a start of the first beam monitoring period.

In the following examples, it will be assumed that BPL may refer to one transmit beam direction or a combination of transmit and receive beam directions. It is also assumed that the radio link evaluation period may include an integer number of BMPs. In each of the following figures, RSx corresponds to BPLx.

In each of fig. 3-8, the UE evaluates the radio link quality based on the evaluation result of the radio link in order to indicate an IS or OOS status to a higher layer. Also, the UE performs radio link assessment using the reference signal for the last X ms, which is referred to herein as a "radio link assessment period". The radio link assessment may be performed, for example, by averaging the measurements of the individual beams during the radio link assessment period.

Turning to fig. 3, one embodiment of the present disclosure will now be described. As shown in fig. 3, the UE has obtained the configuration of both RS0 and RS1 before t0 or t0, and thus the UE can measure the radio channel using both RS0 and RS 1. RS0 and RS1 correspond to BPL0 and BPL1, respectively. Initially, BPL0 is allocated to the UE at t4, so during t4 to t0 the UE uses RS0 based measurements for radio link assessment.

The UE uses RS0 to monitor the beam link quality during BMP to determine if a BPL failure event has occurred. When the UE determines that a BPL0 failure has occurred (at t1 after one BMP in this example), the UE will initiate BRP. The base station responds by assigning a new BPL at t2 (i.e., before the radio link quality assessment time). The newly allocated beam is BPL1 and the UE has RS1 based measurements during t0 to t2, so the UE will evaluate the radio link based on the RS1 measurements from t0 to t5, where t5 is a time within the radio link evaluation period where BMP for BPL1 failure detection starts when BPL1 fails. If the BPL1 does not fail within the radio link evaluation period, t5 is t 3.

In the implementation shown in fig. 4, according to one embodiment, a communication node (e.g., a UE) evaluates the radio channel quality between itself and a second communication node (e.g., a base station or base stations acting in concert) by performing the following actions during a radio link evaluation period: receiving a first reference signal of a first beam link; measuring a radio channel of the first beam link during a first portion of a radio link evaluation period using the first reference signal; and determining, based on the measurement results of the radio channel of the first beam link, that the first beam link has failed before the end of the radio link evaluation period. In this embodiment, the communication node does not receive the second reference signal before the end of the radio link evaluation period. The communication node thus uses the first reference signal (e.g., in response to a determination that the second reference signal has not been received) to evaluate the quality of the radio link between itself and the second communication node during the radio link evaluation period.

As shown in fig. 4, the UE has obtained the configuration of RS0 before t0 or t0, and thus the UE can measure a radio channel using RS 0. Initially, BPL0 is allocated to the UE at t4, so during t4 to t0, the radio link assessment is made using RS0 based measurements.

The UE uses RS0 to monitor beam link quality during BMP to detect BPL failure events. When detecting BPL0 failure at t1 after one BMP, the UE will initiate BRP. However, the UE cannot get a new BPL indication before it evaluates the radio link quality time, so the UE evaluates the radio link using RS 0-based measurements during t0 to t 3.

In the implementation shown in fig. 5, according to one embodiment, a communication node (e.g., a UE) receives a third reference signal of a third beam link; measuring a radio channel of the third beam link using the third reference signal during a third portion of the radio link evaluation period (or, alternatively, evaluating radio channel quality using the third reference signal during the third portion of the radio link evaluation period); determining that the second beam link has failed based on the measurement of the radio channel of the second beam link (or, alternatively, based on the monitored quality); and setting an end of the second portion and a start of the third portion to a time at which the third reference signal is detected based on the determination that the second beam link has failed. In this embodiment, assessing the radio channel quality during the radio link assessment period comprises assessing the radio channel quality based on measurements of the radio channels of the first, second and third beam links (or, alternatively, based on assessment of the radio links within the first, second and third portions (e.g., by averaging the assessment results of the three periods)).

Returning to fig. 5, it will be assumed that the UE has obtained the configuration of both RS0 and RS1 before t0 or t0, so the UE can measure the radio channel using both RS0 and RS 1. RS0 and RS1 correspond to BPL0 and BPL1, respectively. Initially, BPL0 is allocated to the UE at t4, so during t4 to t0 the UE uses RS0 based measurements for radio link assessment. The UE monitors the beam link quality with RS0 during BMP to determine if a BPL failure event has occurred. In this example, there are two BPL failure events.

When detecting BPL0 failure at t1 after one BMP, the UE will start BRP and then the base station allocates a new BPL (i.e., BPL1) at t2 (i.e., before the time when the UE evaluates the radio link quality). The UE has RS 1-based measurements during t0 to t2, so the UE evaluates the radio link using RS 1-based measurements from t0 to t 0'.

At t 1', the UE determines that the BLP1 has failed. After a further BMP, the UE will start another BRP. The base station allocates a new BPL at t 2' (i.e., BPL 2). The UE has RS 2-based measurements during t0 ' to t2 ', so the UE evaluates the radio link from t0 ' to t3 using RS 2-based measurements. Here, it is assumed that no BPL failure has occurred after t 2'.

In the implementation shown in fig. 6, according to one embodiment, a communication node (e.g., UE) measures a radio channel of a first beam link during a first beam monitoring period; determining that the first beam link has failed based on a measurement of a radio channel of the first beam link; and setting a start of the second portion of the radio link evaluation period to an end of the first beam monitoring period.

As shown in fig. 6, the UE has obtained the configuration of both RS0 and RS1 before t0 or t0, but the UE can measure the radio channel using RS 0. The base station allocates BPL0 to the UE at t4, so during t4 to t0, the UE uses the RS 0-based measurement results for radio link evaluation.

The UE monitors the beam link quality with RS0 during BMP to determine if a BPL failure event has occurred. When the UE determines that a BPL0 failure occurs at t1 after one BMP, the UE will initiate BRP. Further, the UE will start to measure the radio channel using RS1 at t 1. The base station allocates a new BPL (i.e., BPL1) at t2 (i.e., before the time when the UE evaluates the radio link quality). The newly allocated beam is BPL1 and the UE has RS1 based measurements during t0 to t2, so the UE will evaluate the radio link from t1 to t5 using RS1 based measurements, where t5 is the time within the radio link evaluation period, and where BMP for BPL1 failure detection is activated when BPL1 fails. If the BPL1 does not fail within the radio link evaluation period, t5 is t 3.

In the implementation shown in fig. 7, according to one embodiment, a communication node (e.g., a UE) measures a radio channel of a first beam link during a first beam monitoring period, measures a radio channel of a second beam link during a second beam monitoring period, and sets a start of one or both of a first portion of a radio link evaluation period and a second portion of the radio link evaluation period to a time at which a corresponding first or second reference signal is received.

In another embodiment (with respect to fig. 7), the communication node determines that the first beam link has failed based on a measurement of a radio channel of the first beam link; receiving a third reference signal of a third beam link; receiving the first reference signal before the third reference signal; receiving a third reference signal before the second reference signal; measuring a radio channel of the third beam link using the third reference signal; and setting an end of the first portion of the radio link monitoring period to a beginning of the first beam monitoring period. The second part of the radio link monitoring period may end before or at the end of the entire radio link monitoring period.

In fig. 7, RS2 may be considered a second reference signal and RS1 may be considered a third reference signal.

In fig. 7, the UE has obtained the configuration of both RS0 and RS1 before t0 or t0, so the UE can measure the radio channel using both RS0 and RS 1. RSx corresponds to BPLx. Initially, BPL0 is allocated to the UE at t4, so during t4 to t0, the radio link assessment is made using RS0 based measurements.

The UE monitors the beam link quality with RS0 during the Beam Monitoring Period (BMP) to detect beam-to-link (BPL) failure events. When detecting BPL0 failure at t1 after one BMP, the UE will initiate BRP. During BRP, a new RS configuration is sent to the UE at t11 and the UE measures the radio channel using RS2 at this time. At t2, BPL2 is allocated to the UE (before the radio link quality assessment time), so the UE evaluates the radio link using measurements from t11 to t5 based on RS2, where t5 is the time within the radio link evaluation period, where BMP for BPL2 failure detection is activated when BPL2 fails. If the BPL2 does not fail within the radio link evaluation period, t5 is t 3.

In another embodiment (with respect to fig. 8), a communication node (e.g., UE) measures a radio channel of a first beam link during a first beam monitoring period; measuring a radio channel of the second beam link during the second beam monitoring period; receiving an indication that a first beam link is available; receiving an indication that a second beam link is available; and setting a start of the first portion of the radio link evaluation period or the second portion of the radio link evaluation period to a time at which an indication of availability of the respective first beam link or second beam link is received.

In fig. 8, it is assumed that the UE has obtained the configuration of both RS0 and RS1 before t0 or t0, and thus the UE can measure a radio channel using both RS0 and RS 1. RS0 and RS1 correspond to BPL0 and BPL1, respectively. At t4, the base station allocates BPL0 to the UE, so during t4 to t0, the UE uses the RS 0-based measurement results for radio link evaluation.

The UE monitors the beam link quality with RS0 during BMP to determine if a BPL failure event has occurred. When the UE determines that a BPL0 failure has occurred at t1 after one BMP, the UE will initiate BRP. If the UE does not store the measurement results for each measurement instance and performs the calculation for the radio link assessment when the measurement result of one measurement instance is acquired, the UE must use the RS 0-based measurement result during t0 to 1 because the BPL0 failure is detected at t 1. After detecting BPL0 failure at t1, the UE will stop evaluating the radio link with RS 0.

A new BPL (i.e., BPL1) is allocated at t2 (i.e., before the radio link quality assessment time) and after t2 the UE starts to evaluate the radio link using RS 1-based measurements (until the time at which BPL1 failure is detected within the radio link evaluation period). This is because the measurement results of the measurement instances (measurements made by the UE) during t1 to t2 are not stored.

It should be understood that the UE may monitor multiple beam links and declare a beam failure based on the detection of several beam links, for example when X of Y beam links fail (X < ═ Y).

It is to be understood that the embodiments described herein are to be considered in all respects only as illustrative and not restrictive. Descriptions of features or aspects in each embodiment are generally considered to be applicable to other similar features or aspects in other embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope thereof. For example, the method steps described herein may be reordered in a manner apparent to those skilled in the art.

Claims

1. A method for assessing radio channel quality between a first communication node and a second communication node during a radio link assessment period, the radio link assessment period having at least a first portion and a second portion, the method comprising:

receiving a first reference signal of a first beam link between the first communication node and a second communication node;

receiving a second reference signal of a second beam link between the first communication node and a second communication node;

measuring a radio channel of the first beam link during the first portion of the radio link evaluation period using the first reference signal;

measuring a radio channel of the second beam link during the second portion of the radio link evaluation period using the second reference signal; and

evaluating radio channel quality during the radio link evaluation period based on the measurement result of the radio channel of the first beam link and the measurement result of the radio channel of the second beam link.

2. The method of claim 1, wherein,

the first reference signal is detected before the second reference signal, and

the first portion ends when the second reference signal is detected.

3. The method of claim 1, wherein,

the first reference signal is detected before the second reference signal, and

the second portion begins when the second reference signal is detected.

4. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

wherein measuring the radio channel of the first beam link is performed during a first beam monitoring period,

wherein measuring the radio channel of the second beam link is performed during a second beam monitoring period,

the method further comprises the following steps:

determining that the first beam link or the second beam link has failed based on the measurement result of the radio channel of the first beam link or the measurement result of the radio channel of the second beam link; and

setting an end of the first portion of the radio link evaluation period or the second portion of the radio link evaluation period as a start of a beam monitoring period during which the first beam link or the second beam link is determined to have failed.

5. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

the method further comprises the following steps:

setting an end of the first portion of the radio link evaluation period or the second portion of the radio link evaluation period as an end of a beam monitoring period within which the first beam link or the second beam link is determined to have failed.

6. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

the method further comprises the following steps:

receiving an indication that the first beam link is available;

receiving an indication that the second beam link is available; and

setting a start of the first portion of the radio link evaluation period or the second portion of the radio link evaluation period to a time at which an indication of availability of the respective first beam link or second beam link is received.

7. The method of claim 1, wherein

Measuring a radio channel of the first beam link is performed during a first beam monitoring period,

measuring the radio channel of the second beam link is performed during a second beam monitoring period,

the method further comprises the following steps: setting a start of one or both of the first portion of the radio link evaluation period and the second portion of the radio link evaluation period to a time at which the corresponding first reference signal or second reference signal is received.

8. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

the method further comprises the following steps:

determining that the first beam link has failed based on a measurement of a radio channel of the first beam link; and

setting a start of the second portion of the radio link evaluation period to a start of a first beam monitoring period.

9. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

the method further comprises the following steps:

setting a start of a second portion of the radio link evaluation period to an end of the first beam monitoring period.

10. The method of claim 1, further comprising:

receiving a third reference signal of a third beam link between the first and second communication nodes;

measuring a radio channel of the third beam link using the third reference signal during a third portion of the radio link evaluation period;

determining that the second beam link has failed based on a measurement of a radio channel of the second beam link; and

setting an end of the second portion and a start of the third portion to a time at which the third reference signal is received based on a determination that the second beam link has failed,

wherein evaluating radio channel quality during the radio link evaluation period further comprises evaluating the radio channel quality based on measurements of radio channels of the respective first, second and third beam links.

11. The method of claim 10, wherein the first and second light sources are selected from the group consisting of,

wherein evaluating the radio channel quality based on the measurements of the radio channels of the respective first, second and third beam links comprises averaging the measurements of the radio channels of the respective first, second and third beam links.

12. The method of claim 1, wherein measuring the radio channel of the first beam link is performed during a first beam monitoring period, the method further comprising:

determining that the first beam link has failed based on a measurement of a radio channel of the first beam link;

receiving a third reference signal of a third beam link between the first communication node and a second communication node;

wherein the first reference signal is detected before the third reference signal and the third reference signal is detected before the second reference signal;

measuring a radio channel of the third beam link using the third reference signal; and

setting a start of a second portion of the radio link monitoring period to a time at which a configuration for the third reference signal is received.

13. The method of claim 12, wherein the second portion ends when the radio link evaluation period ends.

14. The method of claim 13, wherein the second portion ends before the radio link evaluation period ends.

15. The method of claim 1, further comprising initiating the evaluating step only when an indication that the second beam link is available is received before an end of a radio link evaluation period.

16. The method of claim 1, further comprising initiating an evaluation step only if an indication that the second beam link is available is received before a time at which the radio link evaluation is to be performed.

17. The method of claim 1, further comprising initiating an evaluation step only when an indication that the second beam link is available is received within a time window.

18. A method for assessing radio channel quality between a first communication node and a second communication node during a radio link assessment period, the radio link assessment period having at least a first portion and a second portion, the method comprising:

evaluating a radio channel quality of the first beam link during the first portion of the radio link evaluation period using the first reference signal;

evaluating a radio channel quality of the second beam link during the second portion of the radio link evaluation period using the second reference signal; and

evaluating radio channel quality during the radio link evaluation period based on the evaluation of the radio channel quality of the first beam link and the evaluation of the radio channel quality of the second beam link.

19. The method of claim 18, wherein the first and second portions are selected from the group consisting of,

wherein evaluating radio channel quality during the radio link evaluation period based on the evaluation of the radio channel quality of the first beam link and the evaluation of the radio channel quality of the second beam link comprises averaging the evaluation results of the first beam link and the second beam link.

20. The method of claim 18, further comprising:

evaluating a radio channel quality of the third beam link during a third portion of the radio link evaluation period using the third reference signal;

wherein evaluating radio channel quality during the radio link evaluation period further comprises evaluating the radio channel quality by averaging evaluation results of the first, second, and third beam links based on evaluation of radio channel quality of the third beam link in addition to evaluation of radio channel quality of the first beam link and the second beam link.

21. A method for assessing radio channel quality between a first communication node and a second communication node during a radio link assessment period, the radio link assessment period having at least a first portion and a second portion, the method comprising:

during the period of the radio link evaluation period,

measuring a radio channel of the first beam link using the first reference signal;

determining that the first beam link has failed before the end of the radio link evaluation period based on measurements of a radio channel of the first beam link;

determining whether an indication that a second beam link is available has been received; and

based on the determination, evaluating a quality of a radio link between the first communication node and a second communication node during the radio link evaluation period using the first reference signal.

22. The method according to any of claims 1-21, wherein at least one of said beam chains is a receive beam.

23. The method of any one of claims 1-14 and 19, wherein at least one of the beam links is a transmit beam.

24. The method of any of claims 1-21, wherein at least one of the beam links is a beam link pair comprising a transmit beam and a receive beam.

25. The method of any one of claims 1 to 21, wherein one or more of the reference signals are selected from the group comprising: a periodic channel state information reference signal, a synchronization signal, and a demodulation reference signal.

26. A wireless communication system configured to perform the steps of the method according to any one of claims 1 to 21.

27. A communications node configured to perform the steps of the method according to any one of claims 1 to 21.

28. A non-transitory computer readable medium having stored thereon computer executable instructions for performing the method of any one of claims 1 to 21.