Communication channel adaptation method for URLLC service

Abstract

Disclosed is a method for adapting a communication channel of a URLLC service, the method being designed to ensure reliability when performing the URLLC service and being performed in a communication system having at least one transmitter node (eNode) and a receiving or mobile terminal, wherein the receiving or mobile terminal measures an expected signal-to-interference ratio (SIR) using a reference signal received at time t=i-1 and converts the SIR value (SIR) into a desired signal-to-interference ratio (SIR). i‑1 ) is stored in the memory. According to the present invention, the SIR value (SIR i‑1 ), determine the CQI value (CQI i‑1 ) and sends it to the transmitter node (eNode), which transmits the CQI (CQI i‑1 ) selects the modulation and coding format (MCSi) for subsequent transmission in the downlink, wherein, when receiving a data packet sent by the transmitter node (eNode) at time t=i, the receiving terminal measures the SIR (SIRi) and saves it in a memory.

Description

Technical Field

[0001] The present invention relates to 5G mobile communication networks, and more particularly to data services with high latency and reliability requirements. More particularly, the present invention relates to an adaptation method for communication channels for URLLC (Ultra Reliable Low Latency Communication) services. Background Art

[0002] The new generation of mobile networks represents the technical challenge of adapting 4G networks to the speed, latency and reliability requirements demanded by the new 5G services. Examples of the use of next-generation networks include data services with high latency and reliability requirements, also known as URLLC technology. The organization responsible for standardizing the new 5G network technologies is the 3GPP (3rd Generation Partnership Project), which uses the current 4G standards as the basis for defining the new 5G architecture. In this sense, for example, OFDM (Orthogonal Frequency-Division Multiplexing) modulation is still used in 5G in the same way as in LTE (Long Term Evolution), the radio transmission used by 4G networks.

[0003] The new 5G specification defines the feedback of channel status with the same concepts and terms as in 4G technology. The mobile terminal reports the status of the communication channel to the communication node, called Channel State Information (CSI), so that the communication node can estimate the quality of the link and perform resource planning for subsequent transmissions to the terminal in the downlink. This definition is described in 3GPP document TS.38.214, and as part of the channel status report, the mobile terminal determines a communication channel quality indicator called Channel Quality Indicator (CQI).

[0004] Accurate calculation of radio channel state is a key factor in the transition from wireless communication networks to data services with high latency and reliability requirements (URLLC). New 5G networks are being standardized to achieve a latency of approximately 1ms with an error probability of 10 -5 , i.e. a success probability of 99.999%, whereas for the standard in 4G technology a success probability of 90% is used, with a delay of approximately 100ms.

[0005] Generally, a mobile terminal estimates the expected signal-to-interference ratio (SIR) by measuring a reference signal transmitted by a node (eNode) in the downlink. This reference signal is a cell-specific reference signal (CRS) and allows the mobile receiver to perform channel estimation to demodulate data, facilitate mobility, and be used for channel state measurements. This reference signal has a time-frequency grid structure (symbol-subcarrier) that depends on the number of antenna ports, with the reference signal positioned along the grid.

[0006] Based on the SIR measured in the reference signal, the mobile terminal calculates the channel state, or CQI, and reports it to the base station or eNode. This allows the eNode scheduler to take the CQI into account when selecting the subsequent data transmission format, i.e., the modulation and coding scheme (MCS), to be sent in the downlink. This method is often referred to as link adaptation (LA). The reported CQI allows the conditions of the communication channel to be estimated and the transmission to be set to the desired error rate (BLER or BLEP). Therefore, the accurate determination of the CQI is a deterministic factor in the ultimate performance of the communication system.

[0007] The correspondence between the channel quality indicator (CQI) and the modulation and coding format is described in detail in Section 5.2.2 of 3GPP specification TS.38.214. According to the specification, the CQI selected by the mobile terminal will be the highest possible CQI that results in a block error rate (BLER) for the communication below the target. 3GPP defines two possible target BLER values: 10% and 0.001%, the latter of which is specifically defined for URLLC services.

[0008] To determine the correspondence, decision thresholds are defined based on the SIR values ​​calculated by the mobile terminal from the reference signal. These decision thresholds applied to the received SIR to determine the CQI are calculated by applying a target BLER of 10% or 0.001% to the BLER-SIR ratio curve.

[0009] The problem with this approach of applying a threshold to the measured SIR to obtain CQI is that it involves the assumption that the SIR measurement is deterministic and that the threshold for meeting the target BLER is constant over time. However, due to the stochastic nature of wireless communication channels, where radio signals undergo phenomena such as time and / or frequency variations, the premise of a deterministic SIR is not true. Furthermore, the speed of mobile terminals varies over time. Therefore, accurately determining the channel quality reported by the receiver for a particular CQI at each moment is a complex task.

[0010] Furthermore, during the period from when the mobile terminal measures and determines the state of the communication channel defined by the CQI to when the eNode receives the CQI reported by the mobile terminal and performs new planning and transmission in the downlink, the state of the communication channel has changed, so the CQI calculated by the mobile terminal becomes outdated. This imperfection is called outdated CQI[1].

[0011] For services using a target BLER of 10%, several solutions can be found in the prior art that address these problems by moving the threshold applied to the measured SIR to determine the CQI through an algorithm that takes into account whether the data is received with errors or correctly [2]. Thus, if the data is received correctly, the threshold is lowered by a step-down amount (S 降 ) is a predefined amount, and if the reception is erroneous, the threshold increase is defined as a step-up (S 升 ). To meet a specific target BLER, the ramp-up and ramp-down must be connected by the following formula:

[0012]

[0013] However, it should be noted that when the target BLER is very low, such as the 0.001% defined in URLLC services, the step-down must be 10,000 smaller than the step-up. This means that the algorithm will react very slowly to changes, making it useless for this type of service.

[0014] Several methods for improving the accuracy of calculating CQI for both 4G and 5G technologies are described in the prior art. In this sense, for example, US 2012 / 0039207 A1 describes how CQI can be used to control one or more aspects of wireless transmission, compensated according to an aging function that depends on the variability of the channel. More specifically, it proposes a method for calculating an aged channel quality estimate for controlling transmissions on a wireless communication link, the method comprising: (a) estimating the variability of the channel quality for the wireless communication link; and (b) calculating an aged channel quality estimate corresponding to a channel quality estimate determined for the wireless communication link by adjusting the value of each channel quality estimate by an amount that depends on the aging of the channel quality estimate and on the variability of the channel quality estimated for the wireless communication link.

[0015] In other words, US20120039207A1 proposes to calculate the channel variability for each mobile by calculating the correlation or autocorrelation between different time moments of the channel in advance, and based on this variability, applying "back-off" to the calculated CQI through a linear transformation to determine the "aged" CQI, where the higher the variability of the channel, the larger the calculated CQI. The document does not explain how to calculate the correlation or autocorrelation between two time moments, but only mentions a CQI processor that calculates the variability, saves the CQI, and finds the correlation between different time moments. The concept behind the document US20120039207A1 is to calculate two channel quality reports at two time moments and calculate the deviation between them. The historical CQI is saved and used in the decision function of the new corrected CQI, and is also used to measure the new corrected CQI in different subbands to take into account frequency changes.

[0016] Furthermore, in order to minimize the impact of outdated CQI values, a proposal described in EP2529589B1 is found in the prior art, which proposes a channel estimation model for including information about outdated CQI values ​​in the planning algorithm of the transmitter. More specifically, the method described in this document comprises: (a) obtaining at least two channel quality reports at different time instants, each channel quality report comprising channel quality indicators for at least two subbands of a plurality of subbands; (b) estimating a channel quality deviation for at least one subband of the plurality of subbands based on the channel qualities indicated in at least two of the most recently obtained channel quality reports and based on the obtained channel quality indicators for the at least two subbands; and (c) determining a channel quality indicator for at least one subband of the plurality of subbands based on the estimated channel quality deviation for at least one subband of the plurality of subbands.

[0017] In other words, EP2529589B1 describes how a probability distribution function (PDF) of CQI values ​​conditioned on outdated CQI values ​​is used to estimate the BLER currently being achieved during transmission, and how this result is fed back into subsequent planning, taking into account the difference between planned and actual values. This document analyzes proposed improvements for several mobile terminal speeds in planning.

[0018] The problem with the approach described in the previous document is that its ultimate goal is to maximize the effective transmission (throughput) rate of the communication system, but it does not ensure that the final reliability is better than that achieved with the solutions described in the prior art. In this sense, the reliability of the new URLLC service is not related to achieving a high average transmission rate, but rather to ensuring a minimum transmission rate at all times. Therefore, there is still a need for a method that provides a solution to the lack of reliability problem for the new URLLC service.

[0019] In terms of other lines of improvement in CQI estimation, the stringent requirements of new URLLC services in terms of latency and reliability are explained in [1], and three improvements to measuring and reporting CQI in the downlink are proposed. The first improvement is based on estimating CQI for different target error rates or target BLERs by applying different decision thresholds to the SINR values. The second improvement is to enable the configuration of the target BLER based on the duration of the Transmission Interval Time (TTI) and the transmission time of the Hybrid Automatic Repeat Request (HARQ (RTT)). Finally, the third proposal seeks to reduce the impact of CQI mismatch due to variations in the communication channel by mapping the SINR to the CQI based on selecting the worst-case measurement results collected from the channel (m-worst mapping) so as to ensure constant compliance with the target BLER.

[0020] From the proposals described in [1], the most interesting one is the third one, since it seeks to improve CQI mismatch, i.e., to improve outdated CQI. The problem with the proposal described in [1] is that the channel resources are not optimized, since, although it is true that the sporadic BLER will always be the same as or better than the target, the described approach selects the smallest and most stringent CQI among all possible CQIs in each band, without performing finer adjustments in each case. Summary of the Invention

[0021] The present invention relates to a method and apparatus for communication channel adaptation that ensures a certain degree of reliability in URLLC services. This object is achieved by a method according to claim 1 and / or a system according to claim 7 and / or a software product according to claim 13. The dependent claims describe preferred and / or embodiments of the invention.

[0022] Indeed, the technical problem addressed by the apparatus and method of the present invention relates to ensuring reliability according to the indices proposed herein. This reliability should not be confused with the concept of effective transmission or throughput, which is defined as the "net" rate, i.e., once errors are excluded. Unlike other solutions in the prior art, the present invention does not directly guarantee an effective transmission rate. Instead, it aims to provide each mobile terminal with the highest speed possible by satisfying the reliability index.

[0023] The concept of a reliability index is introduced because, as described in the prior art, when the target BLER is very low (0.001%), as in URLLC services, the threshold adaptation mechanism does not work. However, the reliability index, as defined below, allows the use of calculated thresholds to meet the 0.001% BLER, while allowing these thresholds to be adapted to the conditions of each mobile by using the index, which can be very high (on the order of 90%, or in other words, 10% non-compliance), which allows for rapid adaptation. In other words, the problem of preventing the thresholds from being adapted to the user's conditions, or generally speaking, the problem of the choice of transport format, is solved in a fast and efficient manner.

[0024] Although the method of the present invention is not limited to a particular type of mobile technology, the present invention will preferably be applied to 5G technology based on 4G or LTE technology. Therefore, with adjustments to the terminology, the method of the present invention is equally applicable to other radio technologies.

[0025] As a result of the present invention, the lack of precision in CQI estimation can be alleviated by a method that ensures a minimum success rate for the service, so that the data in the first transmission reaches the receiver meeting the target error rate for the service and without the need for continuous retransmissions that would result in a worse fixed delay target.

[0026] The scope of the present invention is defined by the claims, which are incorporated into this section by reference. Throughout the specification and claims, the word "comprise" and its variants do not seek to exclude other technical features, components or steps. For those skilled in the art, other objects, advantages and features of the present invention will be inferred in part from the specification and in part from the practice of the present invention. The following use examples and associated drawings are provided in an illustrative and non-restrictive manner. In addition, the present invention covers all possible combinations of the specific and preferred embodiments indicated herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] There will now be described very briefly a series of drawings and diagrams which facilitate a better understanding of the invention and which relate expressly to an embodiment of said invention presented as a non-limiting example thereof.

[0028] Figure 1 The next generation (5G) network structure is shown.

[0029] Figure 2 A time-frequency grid with signal planning is shown.

[0030] Figure 3 An operational diagram of a prior art method is shown.

[0031] Figure 4 A diagram showing determination of a CQI threshold is shown.

[0032] Figure 5 A diagram illustrating the operation of the method of the present invention is shown. DETAILED DESCRIPTION

[0033] For example, Figure 1 A diagram showing the structure of a next generation (5G) mobile communication network as described in the prior art. The structure comprises at one communication end a user mobile terminal to which voice and data services are provided, and at the other end a communication network, the first access point of which is a base station or communication node referred to as an eNode in 4G and 5G terminology. The network consists of a plurality of base stations or eNodes (hereinafter, base stations or eNodes will be referred to as "nodes" to simplify the notation), each of which provides services to a group of mobile terminals located in a coverage area. The coverage area of ​​each node is further subdivided into different coverage cells, which provide 360-degree coverage of the area around the node and have their own radio resources. These cells are located in the Figure 1 Depicted as a hexagon.

[0034] exist Figure 2 In the figure, reference signals are depicted in black, representing a typical time-frequency grid for resource planning in LTE. Data and control information are multiplexed in time and frequency using this grid, which has a time dimension of 1 ms and a frequency dimension of 180 kHz, for different transmissions. These reference signals are then used by the receiver to determine link quality.

[0035] Figure 3 The prior art prior to the present invention is illustrated in a diagram in terms of a method for determining CQI and the associated problem that the CQI is not updated to the actual link quality at the moment the transmitter receives feedback from the receiver and performs new data planning. In this sense:

[0036] - At time t=i-1, the mobile terminal (receiver) Figure 2 The mode shown receives a reference signal and uses it to estimate the expected signal-to-interference ratio (SIR i-1 ). By applying a threshold algorithm, the receiver determines the CQI from the measured SIR i-1 value and sends it to the node (eNode or transmitter).

[0037] - At time t = i-1 + Δ, the transmitter receives the CQI reported by the mobile terminal i-1 value, and determines the modulation and coding format (MCS) of the data to be transmitted corresponding to the received CQI in the downlink, that is, MCS i =f(CQI i-1 ). Again, the node encodes the data to be transmitted according to the determined format (DATA(MCSi )) and sends it to the mobile terminal (receiver).

[0038] - At time t=i, the mobile terminal receives data accompanied by the data transmitted by the transmitter according to the CQI i-1 The reference signal is sent, the SIR level is calculated, and the received data is demodulated. In parallel, the communication quality is measured in terms of BLER based on the received signal. Finally, Figure 3 Describes how the mobile terminal (receiver) determines the channel quality from the measured SIR and determines the CQI i , to be sent to the node (transmitter) for subsequent transmission.

[0039] Figure 4 A method for determining the threshold value to be applied by the mobile terminal to the SIR is depicted. The mobile terminal internally uses a threshold algorithm based on these curves to be able to determine the CQI sent to the transmitter node for subsequent planning in the downlink. The target communication quality (target BLER) is depicted in the figure by the horizontal line 401 and typically takes a value of 10% or 0.001%. The CQI must be determined so that it ensures that the error is less than the target rate of the SIR measured by the receiver or mobile terminal. Therefore, the threshold is defined as the cut-off point of the SIR-BLER curve for different CQIs and the horizontal line of the target BLER, and the threshold SIR value is obtained from these correspondences.

[0040] Figure 5 The diagram depicts an operation of a preferred embodiment of the method object of the present invention. To this end, an example of communication between a mobile terminal and a node (eNode), ie a communication receiver and a transmitter depicted as its two ends, and information exchange between them is shown.

[0041] The method of the present invention aims to Figure 1 In a wireless communication system such as the one shown in FIG, a receiver or mobile terminal measures a desired signal-to-interference ratio (SIR) based on a reference signal received at time t=i-1 and uses the SIR value (SIR i-1 ) is stored in the memory. i-1 ), determine the CQI value (CQI i-1 ) and sends it to the transmitter node, which transmits the CQI according to the measured CQI (CQI i-1 ) selects the modulation and coding format (MCSi) for subsequent transmission in the downlink. When receiving a data packet sent by the transmitter node at time "t", the receiver terminal measures the SIR (SIR i ) and save it in memory.

[0042] The present invention proposes that the receiver or mobile terminal calculate the parameter (α i ), which parameter allows the variation experienced by the communication channel between said transmissions to be determined. Thus, the variation quantification parameter (α) of the communication channel i ) accurately reflects the CQI (CQI) determined by the reference signal i-1 ) moment and the receiver mobile terminal receives the CQI in subsequent reception i-1 The corresponding data and measure the channel quality (CQI i ) as the difference in channel quality used as a reference.

[0043] In a preferred embodiment of the present invention, the variation quantization parameter (α) of the communication channel i ) is defined as the difference between the SIR values ​​measured by the receiver mobile terminal to quantify the variations experienced in the communication channel. In other words:

[0044] α i =SIR i –SIR i-1

[0045] Nevertheless, the variation of the communication channel quantization parameter (α i ) can be defined in terms of other time variations or differences, since, unlike other methods described in the state of the art, the present invention does not have frequency variations or discrimination. The variation quantization parameter (α) of the communication channel i ) will be performed by calculating the variation of the CQI value such that:

[0046] α i =CQI i –CQI i-1

[0047] Those skilled in the art will understand that other variations of this definition are also valid for the purposes of the present invention, such as the difference between the average or weighted values ​​of SIR or CQI measurements for different frequency bands, or the use of values ​​corresponding to two or more time moments with the same coefficient weights, in the case where there is uncertainty as to which measurement moment i-1 is the measurement moment that brings about the determination of the data received at i.

[0048] The second key point of the present invention is to calculate the correction margin by a conversion function, the two input parameters of which are the variation quantization parameters (α i ) and on the other hand the target reliability to be fixed for the communication of the services provided. In this sense:

[0049] Margin i =f(α i , target reliability)

[0050] The target reliability is the value for the reliability index to be ensured by the present invention, and the reliability index can be defined according to the following formula:

[0051]

[0052] Among them BLERi i is the actual instantaneous block error rate, and BLER 目标 is the target average block error rate for the service.

[0053] In the present invention, it is necessary to use the concept of defining a reliability index to supplement the target average block error rate (BLER) of 5G services. 目标 ) concept, because, as mentioned above, although BLER 目标 On average the requirements are met, but due to inaccurate determination of the CQI it occasionally does not meet the requirements for all transmissions, which results in the final delay of the system occasionally not being met in all cases. The present invention proposes to ensure that the reliability index is greater than a certain target reliability for the service by applying a correction margin to the calculation of the CQI performed by the mobile terminal before reporting the CQI to the transmitter node.

[0054] As mentioned above, due to such low target error rates used in URLLC services, it is not efficient to correct the calculation of CQI directly based on the received block errors. However, indirect correction through a defined reliability index allows the use of higher reliability, allowing efficient correction compatible with the use of very low target block error rates.

[0055] If the reliability index is defined as the percentage of blocks or time that must meet the maximum BLER established for the service used, then the invention will have the following effect: once the channel state is modified and therefore the CQI is sent to the transmitter, the final block error rate of the system will be the target rate for the percentage of time determined by the fixed target reliability (10% in the case of LTE, or lower in URLLC services).

[0056] The reliability index is measured indirectly because the true instantaneous block error rate cannot be measured directly. Figure 4 As described above, there is a direct relationship between the error rate and the received SIR or estimated CQI. The embodiments described below assume that if the conditions (e.g., SIR or CQI) when receiving the data are worse than when the transmission format used to transmit the data was determined, this means that the instantaneous block error rate will be higher than the target block error rate. In other words, the present invention is due to the changing quantization parameter (α) of the defined communication channel. i ) can be used as a basis for calculating a reliability index, which in turn allows the CQI to be corrected in order to adapt it to the conditions faster than the BLER.

[0057] A first embodiment of the step of calculating the correction margin is to calculate the value of the communication channel variation quantization parameter (α i ) distribution function to calculate the correction margin. As defined above, the concept of reliability index is statistically equivalent to the cutoff percentile or probability. Specifically, in order to ensure that the channel has a reliability index higher than a certain target reliability, it is necessary to use a reliability index based on α i The margin around the percentile of the distribution (100% - target reliability).

[0058] According to this embodiment, the calculation of the correction margin based on SIR or CQI will include the following steps: obtaining the variation quantization parameter (α i )

[0059] The n% percentile of the distribution is determined, where n = 100% - target reliability, and where the n% percentile is defined as the value below which n% of the obtained values ​​are found.

[0060] Determine the margin based on the percentiles i :

[0061] Margin i =Percentile_α i (100% - target reliability)

[0062] Another possible implementation of this second step of determining the correction margin includes an algorithm that iteratively approaches the percentile value corresponding to the target reliability described in the previous embodiment. Specifically, in this embodiment, the percentile estimate increases with the α calculated by the mobile device. i Each new value is updated by an increasing amount (S 升 ) or descending amount (S 降 ) to increase or decrease its value. The target reliability defines the ratio between two steps, which must satisfy the following expression:

[0063]

[0064] To update the margin i The iterative process is performed as follows:

[0065] If α i >Margin i-1 , then the margin i =margin i-1 –S 降 ;

[0066] If α i <Margin i-1 , then the margin i=margin i-1 +S 升 .

[0067] This method is advantageous over the previous method because it does not require storing the old α i value, thereby reducing memory usage.

[0068] According to the method proposed in this invention, the CQI reported to the transmitter is successfully adjusted to eliminate the effects of varying channel conditions between the time the receiver calculates the CQI and the time the transmitter performs data planning in the downlink. The described method applies a correction margin to the CQI calculation determined by channel variations; it is conceptually equivalent to modifying the decision threshold for the SIR-CQI mapping performed by the receiver when it measures and reports a reference signal to the transmitter, making it more demanding. Setting a higher level for the decision threshold means that it will be biased toward higher SIR values, resulting in a lower CQI for the same SIR than the previous one.

[0069] Examples of practical implementations of the invention

[0070] As mentioned above, in Figure 5 The diagram of the operation of a preferred embodiment of the method according to the present invention is shown in FIG. For this purpose, an excerpt of a communication between a mobile terminal and a node (eNode), i.e., a communication receiver and a transmitter, represented as its two ends, is shown, as well as the information exchange between them. In this sense, each time the mobile receiver receives data in the downlink, the downlink performs the following steps at time i:

[0071] Estimate the expected signal-to-interference ratio (SIR) of the received i ); Save SIR i value;

[0072] Determine the SIR error value, which is defined as the SIR SIR at time [i-1] i-1 and SIRSIR at the current moment [i] i The difference between i =SIR i –SIR i-1 ; Save α i value;

[0073] The correction margin is calculated by applying the desired reliability index to the statistical data, where

[0074] Margin i =f(α, reliability);

[0075] In determining the SIR i Before the corresponding CQI, by applying the correction margin, the margini To correct the SIR SIR measured by the terminal at the current moment i , making SIR i '=SIR i +Margin i ; and determining the expected signal-to-interference ratio SIR with the received and corrected i 'The corresponding CQI, that is, CQI i .

[0076] References

[0077] [1] Pocovi, G., Shariatmadari, H., Berardinelli, G., Pedersen, K., Steiner, J., & Li, Z. (2018). "Achieving ultra-reliable low-latency communications: Challenges and envisioned system enhancements". IEEE Network, 32(2), 8-15.

[0078] [2] Michiharu Nakamura, Yassin Awad and Sunil Vadgama (2002). “Adaptive Control of Link Adaptation for High Speed ​​downlink Packet Access (HSDPA) in W-CDMA”, Fujitsu Laboratories Europe Ltd., IEEE Transactions on Communications.

Claims

1. A communication channel adaptation method for a URLLC service, the method being performed in a communication system having at least a transmitter node (eNode) and a receiver or mobile terminal; in, The receiver or mobile terminal measures the expected signal-to-interference ratio SIR based on the reference signal received at time t=i-1 and converts the SIR value SIR i-1 Save in memory; According to the SIR value SIR at time t=i-1 i-1 , determine the CQI value CQI i-1 The CQI value is sent to the transmitter node eNode, and the transmitter node measures the CQI value CQI at time t=i-1. i-1 Select the modulation and coding format (MCS) for subsequent transmissions in the downlink i ; And wherein, when receiving a data packet sent by the transmitter node eNode at time t=i, the receiver terminal measures the SIR value SIR i And the SIR value SIR i The method is characterized in that the method comprises the following steps: Calculate the change quantization parameter α of the communication channel i The variation quantization parameter is defined as the difference between the channel qualities used as references at the following two moments, one of which is a moment where the CQI value CQI is determined by a reference signal. i-1 The other of the two moments is the moment when the receiver mobile terminal receives the CQI in the subsequent reception i-1 Corresponding data and measuring the channel quality CQI again i moment; At least according to the variation quantization parameter α of the communication channel i Multiple values ​​of the correction margin are used to calculate the margin i ; By applying the calculated correction margin i To correct the SIR value SIR measured by the terminal at time t = i i , so that the corrected SIR value SIR' at time t = i i Equal to the SIR value SIR at time t=i i plus the correction margin i and Determine the expected signal-to-interference ratio SIR' at time t = i compared to the received and corrected signal i Corresponding CQI value CQI' i ; The method further comprises establishing a reliability index defined as follows: Among them, BLER i is the actual instantaneous block error rate, and BLER 目标 is the target average block error rate of the URLLC service required by the receiver or mobile terminal; so that the correction margin margin i The calculation of is performed by a transformation function, the two input parameters of which are the variation quantization parameter α of the communication channel i and on the other hand a target reliability established for the calculated reliability index.

2. The method according to claim 1, wherein The variation quantization parameter α of the communication channel i is defined as the difference between the SIR values ​​measured by the receiver mobile terminal to quantify the variations experienced in the communication channel, such that α i =SIR i –SIR i-1 .

3. The method according to claim 1, wherein The variation quantization parameter α of the communication channel i is defined as the calculation of the change in the CQI value such that α i =CQI i –CQI i-1 .

4. The method according to any one of claims 1 to 3, comprising obtaining the variation quantization parameter α of the communication channel i a plurality of values ​​obtained; determining an n% percentile of the distribution, where n% = 100% - target reliability, and where the n% percentile is defined as the value below which n% of the plurality of values ​​obtained lie; and determining the correction margin margin based on the percentile i : Margin i =Percentile_α i (100% - target reliability).

5. The method according to any one of claims 1 to 3, wherein The correction margin margin i is iteratively calculated as a percentile value corresponding to the target reliability, so that the percentile estimate value varies with the variation quantization parameter α of the communication channel calculated by the mobile device. i Each new value is updated by an increment of S 升 Or descending amount S 降 To increase or decrease the value of the percentile estimate, the target reliability defines the ratio between the step-up and step-down amounts, which must satisfy the following expression: The iterative process of updating the margin i is performed as follows: If α i >Margin i-1 , then the margin i =margin i-1 –S 降 ; If α i <Margin i-1 , then the margin i =margin i-1 +S 升 .

6. A communication system having at least a transmitter node and a receiver or terminal: in, The receiver or mobile terminal is configured to measure the expected signal-to-interference ratio SIR based on the reference signal received at time t=i-1 and convert the SIR value SIR i-1 stored in a memory; and wherein the receiver or mobile terminal is further configured to determine the SIR value SIR at time t=i-1 i-1 Determine the CQI value CQI i-1 And the CQI value CQI i-1 Send to the transmitter node eNode; And wherein the transmitter node eNode is configured to be used for according to the CQI value CQI measured at time t=i-1 i-1 Select the modulation and coding format (MCS) for subsequent transmissions in the downlink i ; And wherein, when receiving a data packet sent by the transmitter node eNode at time t=i, the receiver terminal measures the SIR value SIR i And the SIR value SIR i Save in memory; The receiver or mobile terminal includes at least one or more processors and one or more programs, wherein the programs are stored in one or more memories and configured to be executed by the one or more processors, and wherein the programs include instructions for: Calculate the change quantization parameter α of the communication channel i The variation quantization parameter is defined as the difference between the channel qualities used as references at the following two moments, one of which is a moment where the CQI value CQI is determined by a reference signal. i-1 The other of the two moments is the moment when the receiver mobile terminal receives the CQI in the subsequent reception i-1 Corresponding data and measuring the channel quality CQI again i moment; At least according to the variation quantization parameter α of the communication channel i Multiple values ​​of to calculate the correction margin margin i ; By applying the calculated correction margin i , to correct the SIR value SIR measured by the terminal at time t = i i , so that the corrected SIR value SIR' at time t = i i Equal to the SIR value SIR at time t=i i plus the correction margin i and Determine the expected signal-to-interference ratio SIR' at time t = i compared to the received and corrected signal i Corresponding CQI value CQI' i ; The program also includes instructions for establishing a reliability index defined as follows: Among them, BLER i is the actual instantaneous block error rate, and BLER 目标 is the target average block error rate of the URLLC service required by the receiver or mobile terminal; so that the correction margin margin i The calculation of is performed by a transformation function, the two input parameters of which are the variation quantization parameter α of the communication channel i and on the other hand a target reliability established for the calculated reliability index.

7. The system according to claim 6, wherein: The variation quantization parameter α of the communication channel i is defined as the difference between the SIR values ​​measured by the receiver mobile terminal to quantify the variations experienced in the communication channel, such that α i =SIR i –SIR i-1 .

8. The system according to claim 6, wherein: The variation quantization parameter α of the communication channel i is defined as the calculation of the change in the CQI value such that α i =CQI i –CQI i-1 .

9. The system according to any one of claims 6 to 8, comprising obtaining the variation quantization parameter α of the communication channel. i ; determine the n% percentile of the distribution, where n%=100%-target reliability, and wherein the n% percentile is defined as the value below which n% of the plurality of values ​​obtained lie; and determining the correction margin margin based on the percentile i : Margin i =Percentile_α i (100% - target reliability).

10. The system according to any one of claims 6 to 8, wherein The correction margin margin i is iteratively calculated as a percentile value corresponding to the target reliability, so that the percentile estimate value varies with the variation quantization parameter α of the communication channel calculated by the mobile device. i Each new value is updated by an increment of S 升 Or descending amount S 降 To increase or decrease the value of the percentile estimate, the target reliability defines the ratio between the step-up and step-down amounts, which must satisfy the following expression: And among them, the update margin i The iterative process is performed as follows: If α i >Margin i-1 , then the margin i =margin i-1 –S 降 ; If α i <Margin i-1 , then the margin i =margin i-1 +S 升 .

11. A software product comprising instructions configured to be executed by one or more processors, wherein when the instructions are executed, the instructions cause the system according to any one of claims 6 to 10 to perform the method according to any one of claims 1 to 5.

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