CN108702738A - A kind of method of feedback channel quality, user equipment and base station - Google Patents

A kind of method of feedback channel quality, user equipment and base station Download PDF

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Publication number
CN108702738A
CN108702738A CN201780008149.6A CN201780008149A CN108702738A CN 108702738 A CN108702738 A CN 108702738A CN 201780008149 A CN201780008149 A CN 201780008149A CN 108702738 A CN108702738 A CN 108702738A
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channel quality
power
base station
value
allocated
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兰洋
李安新
蒋惠玲
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NTT Docomo Inc
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NTT Docomo Inc
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W28/00—Network traffic management; Network resource management
    • H04W28/16—Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/54—Allocation or scheduling criteria for wireless resources based on quality criteria
    • H04W72/542—Allocation or scheduling criteria for wireless resources based on quality criteria using measured or perceived quality
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/02—Selection of wireless resources by user or terminal

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  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

This application discloses a kind of method of feedback channel quality, user equipment and base stations.The process of this method includes:The first downlink signal sent out at the first moment is received, the first channel quality value is estimated according to the first downlink signal;The second downlink signal that second moment of the reception after first moment sends out, second channel mass value when estimating that base station carries out multi-user transmission according to second downlink signal, wherein, the multi-user transmission is the downlink transfer that base station is carried out using identical running time-frequency resource to multiple UE including the first UE;Channel quality Dynamic gene is calculated according to the first channel quality value and second channel mass value, and channel quality Dynamic gene is fed back into base station.

Description

Method for feeding back channel quality, user equipment and base station Technical Field
The present application relates to mobile communication technologies, and in particular, to a method, a user equipment and a base station for feeding back channel quality.
Background
In a wireless communication system, a base station generally needs User Equipment (UE) to feed back channel quality in order to schedule users, and then determines a Modulation and Coding Scheme (MCS), time-frequency resources, and the like used by each user for downlink transmission according to the channel quality fed back by each UE.
Technical content
In view of this, the present application provides a method for adjusting channel quality, which aims to improve accuracy of downlink scheduling. Accordingly, system throughput as well as user throughput can be improved to some extent.
The embodiment of the application provides a method for feeding back channel quality, which is applied to first User Equipment (UE) and comprises the following steps:
receiving a first downlink signal sent out at a first moment, and estimating a first channel quality value according to the first downlink signal;
receiving a second downlink signal sent at a second time after the first time, and estimating a second channel quality value when the base station performs multi-user transmission according to the second downlink signal, wherein the multi-user transmission is downlink transmission performed by the base station to a plurality of UEs including the first UE by using the same time-frequency resource; and
and calculating a channel quality adjusting factor according to the first channel quality value and the second channel quality value, and feeding back the channel quality adjusting factor to a base station, so that the base station can adjust the channel quality of the first UE during multi-user transmission estimated by the base station according to the channel quality adjusting factor and perform multi-user transmission by using the adjusted channel quality.
An embodiment of the present application provides a user equipment UE, including:
the receiving module is used for receiving a first downlink signal sent at a first moment and a second downlink signal sent at a second moment after the first moment;
an estimating module, configured to estimate a first channel quality value according to the first downlink signal, and estimate a second channel quality value when the base station performs multi-user transmission according to the second downlink signal, where the multi-user transmission is downlink transmission performed by the base station to multiple UEs including the first UE using the same time-frequency resource;
a calculation module for calculating a channel quality adjustment factor based on the first channel quality value and the second channel quality value; and a process for the preparation of a coating,
and the feedback module is used for feeding the channel quality adjusting factor back to the base station, so that the base station adjusts the channel quality of the first UE during multi-user transmission estimated by the base station according to the channel quality adjusting factor and performs multi-user transmission by using the adjusted channel quality.
An embodiment of the present application provides a base station, including:
a sending module, configured to send a first downlink signal at a first time, so that a first user equipment UE estimates a first channel quality value according to the first downlink signal; sending a second downlink signal at a second time after the first time, so that the first UE estimates a second channel quality value when the base station performs multi-user transmission according to the second downlink signal, and calculates a channel quality adjustment factor according to the first channel quality value and the second channel quality value, wherein the multi-user transmission is downlink transmission performed by the base station to a plurality of UEs including the first UE by using the same time-frequency resource;
a receiving module, configured to receive the channel quality adjustment factor fed back by the first UE;
and the scheduling module is used for determining a Modulation and Coding Scheme (MCS) used by the downlink signal of the first UE when multi-user transmission is carried out according to the channel quality adjustment factor.
According to the technical scheme, the method for feeding back the channel quality in the mobile communication system, the user equipment and the base station provided by the embodiment of the application, the UE calculates the channel quality adjustment factor and feeds back the channel quality adjustment factor to the base station, so that the base station can obtain the channel quality deviation estimated by the UE. Further, the base station can determine the MCS used when the downlink signal of the UE is transmitted when the multi-user transmission is really carried out, so that the accuracy of the MCS in the subsequent transmission is effectively improved, and the system throughput and the user throughput are improved.
Brief description of the drawings
Fig. 1a is a schematic flowchart of a method for feeding back channel quality according to an embodiment of the present application;
fig. 1b is a schematic flowchart of a method for feeding back channel quality in an embodiment of the present application;
FIG. 2 is a diagram illustrating multi-user transmission in an embodiment of the present application;
FIG. 3 is a flowchart illustrating a method for adjusting CQI in an embodiment of the present application;
fig. 4a is a schematic diagram of a probability distribution of an interference power adjustment value in an embodiment of the present application;
fig. 4b is a schematic diagram of a probability distribution of interference power adjustment values in the embodiment of the present application;
FIG. 5 is a signaling interaction diagram of a method for adjusting CQI in an embodiment of the present application;
FIG. 6 is a flowchart illustrating a method for adjusting CQI in an embodiment of the present application;
fig. 7 is a schematic structural diagram of a user terminal in an embodiment of the present application;
fig. 8 is a schematic structural diagram of a base station in the embodiment of the present application.
Modes for carrying out the present application
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below by referring to the accompanying drawings and examples.
Fig. 1a is a flowchart illustrating a method for feeding back channel quality in an embodiment of the present application, where the method is applied to a first UE and includes the following steps.
Step 11, receiving a first downlink signal transmitted at a first time, and estimating a first channel quality value according to the first downlink signal.
The first downlink signal (also referred to as first downlink data) is a downlink signal, for example, a pilot signal, which is transmitted from the base station to the first UE for channel estimation. The pilot signal may be a downlink Reference Signal (RS), such as a Cell Reference Signal (CRS), a UE-specific reference signal (UE-specific RS), and so on.
The channel quality value is a value representing the channel quality. The channel quality value may be, for example, a signal to interference plus noise ratio (SINR), a signal to noise ratio (SNR), a signal to interference ratio (SIR), a carrier to interference ratio (CIR), a Reference Signal Received Quality (RSRQ), etc.
And step 12, receiving a second downlink signal sent at a second time after the first time, and estimating a second channel quality value when the base station performs multi-user transmission according to the second downlink signal.
The multi-user transmission refers to downlink transmission performed by a base station to a plurality of UEs including the first UE by using the same time-frequency resource.
The second downlink signal (also referred to as second downlink data) refers to a downlink signal transmitted by the base station to the first UE for performing multi-user transmission, for example, a control signal for multi-user transmission. The first UE may obtain parameters of the multi-user transmission from the second downlink signal, and estimate the second channel quality value using the parameters of the multi-user transmission. The parameters of the multi-user transmission may include: the power and precoding matrix allocated to the first UE, and the power allocated to at least one second UE of the plurality of UEs, for multi-user transmission.
And step 13, calculating a channel quality adjustment factor according to the first channel quality value and the second channel quality value, and feeding back the channel quality adjustment factor to the base station.
The base station may adjust, according to the channel quality adjustment factor, the channel quality of the first UE during the multi-user transmission estimated by the base station, and perform the multi-user transmission by using the adjusted channel quality.
In the embodiment of the application, the UE estimates the channel quality during multi-user transmission according to the multi-user transmission condition, calculates the channel quality adjustment factor according to the channel quality and feeds back the channel quality adjustment factor to the base station. Therefore, the base station can adjust the estimated value of the channel quality of the UE during multi-user transmission by using the channel quality adjusting factor and perform multi-user transmission according to the adjusted estimated value, thereby effectively improving the accuracy of the MCS during subsequent transmission and improving the system throughput and the user throughput.
Fig. 1b is a schematic flow chart of a method for feeding back channel quality in the embodiment of the present application. The method is applied to a first UE. In this embodiment, the SINR is taken as an example of the channel quality value. The method comprises the following steps.
Step 101, receiving first downlink data sent at a first time, and estimating a first SINR according to the first downlink data.
Herein, downlink data may refer to user data, pilot data, or control signaling data.
In a particular implementation, the SINR is the ratio of the received strength of the desired signal to the received strength of the interfering signal and noise. The first downlink data may be a downlink Reference Signal (RS), such as a Cell Reference Signal (CRS). The first UE may obtain a first SINR from the received RS estimate, which is expressed as:
wherein, the SINR1Representing a first SINR, PRSRPIndicating the received power of the RS, PIntN is the noise power, i.e. the sum of the signal powers of the adjacent cells received on the resource block occupied by the RS.
And 102, estimating a second SINR according to the received second downlink data.
And the second downlink data is sent out at a second moment after the first moment. The second downlink data includes data to be transmitted to the first UE. Thus, the first UE estimates a second SINR from the received data signal, which is expressed as:
wherein, the SINR2Representing the second SINR, PdataIndicating the received power, P, of the received data signalIntN is the noise power, which is the sum of the signal powers of the neighboring cells received on the resource blocks occupied by the data sent to the first UE.
Step 103, calculating a CQI adjustment factor (i.e. a channel quality adjustment factor) according to the first SINR and the second SINR, and feeding back the CQI adjustment factor to the base station.
In an embodiment, calculating the CQI adjustment factor γ may be expressed as:
γ＝f(SINR1，SINR2) (3)
wherein, the SINR1The representative is the channel quality parameter of the reference signal sent by the second downlink data base station; SINR2Representative is the channel quality parameter of the data signal when the second downlink data is actually transmitted. That is, the SINR is seen from the downlink data to be transmitted to the first UE1Can be understood as an estimated value, SINR2Which can be understood as the true value. According to SINR1And SINR2The difference between them is used to estimate the CQI adjustment factor, represented by the function fO.
In a typical scenario of multi-user transmission, as shown in fig. 2, a base station serves multiple users UE1, UE2, UE3, and UE4 simultaneously. Depending on whether the resources allocated to the users are orthogonal, the base station may determine whether to employ orthogonal multi-user multiple antenna (MU-MIMO) transmission or non-orthogonal multiple access (NOMA) transmission.
Specifically, MU-MIMO transmission belongs to an orthogonal multiple access technique, allocating orthogonal resources to multiple users, e.g., simultaneously signaling UE1 and UE3 in fig. 2 using different spatial resources. In NOMA transmission, the same resource can be allocated to multiple users, for example, the channel quality difference between UE1 and UE2 in fig. 2 is large, the base station allocates non-orthogonal resources to UE1 and UE2 during downlink scheduling, for example, the same time-frequency resource block is used but different powers are allocated. In this way, the channel quality difference of a plurality of users can be converted into multiplexing gain, and the UE side can perform demultiplexing by adopting the serial interference cancellation technology. Similarly, UE3 and UE4 may also employ NOMA transmission.
For MU-MIMO transmission, take UE1 and UE3 as examples, where the first UE may be UE1, and UE1 cannot know that the interference from UE3 and the interference generated by other UEs in the neighboring cell are received when downlink data is actually transmitted at the second time (i.e., multi-user transmission) when CQI is fed back. Here, since the UE1 and the UE3 employ orthogonal resources, the above interference mainly originates from other UEs in neighboring cells.
For NOMA transmission of non-orthogonal resources, taking UE1 and UE2 as an example, where the first UE may be UE1, since they are non-orthogonal in power dimension, UE1 cannot know the interference introduced by UE2 when transmitting and pairing with multi-user and the interference generated by other UEs in neighboring cells when feeding back CQI, where the interference mainly originates from UE2 paired in the same cell due to non-orthogonal transmission.
As can be seen, for orthogonal MU-MIMO or non-orthogonal NOMA transmission, the CQI fed back to the base station by the UE1 is greatly different from the actual CQI during actual downlink data transmission, so that the accuracy of the MCS determined by the base station during scheduling is reduced, and therefore, the CQI referred to during scheduling needs to be adjusted.
According to the method provided by the embodiment, the first UE estimates the CQI adjustment factor according to SINRs at the front and rear moments and feeds the CQI adjustment factor back to the base station, so that the base station can determine the MCS used in the subsequent multi-user transmission according to the CQI adjustment factor, the accuracy of the MCS in the multi-user transmission can be effectively improved, and the system throughput and the user throughput are improved.
Fig. 3 is a flowchart illustrating a method for adjusting CQI according to another embodiment of the present application. The method is applied to a first UE and comprises the following steps.
In step 301, a plurality of candidate adjustment values are preset.
The value of the alternative adjustment value (also called alternative CQI adjustment value) may be set to a fixed value in advance by the first UE, or may be quantized by the first UE based on the interference power adjustment value λ. the specific method based on the interference power adjustment value λ is given in step 304. the first UE will store the interference power adjustment value λ calculated each time, and obtain L alternative CQI adjustment values α 1, …, α L through the following steps.
Step 3011, statistics is performed on the probability distribution of the interference power adjustment value calculated before the second time.
And step 3012, determining a probability value p corresponding to each interference power adjustment value according to the probability distribution.
Step 3013, grouping the probability values.
Presetting a probability threshold pth, taking out all probability values p1, … and pM which are larger than the probability threshold, then dividing the probability values with similar values into a group, wherein the number of the probability values in each group can be the same or different.
Step 3014, average the interference power adjustment values λ corresponding to the probability values in each group, and determine the obtained average value as L candidate CQI adjustment values.
For example, when L is 4, α 1 is-0.1, α 2 is 0.1, α 03 is 0.23, α 14 is 0.56, and, for example, when L is 8, α 1 is-0.3, α 2 is-0.15, α 3 is 0, α 4 is 0.1, α 5 is 0.2, α 6 is 0.3, α 7 is 0.5, α 8 is 0.7, and meanwhile, the value of L also affects the transmission resources occupied by the feedback CQI adjustment values.
Fig. 4a is a schematic diagram of probability distribution of interference power adjustment values, corresponding to L ═ 4, as shown in fig. 4a, the horizontal axis is a value of the interference power adjustment value, the number axis is a value of probability, each interference power adjustment value corresponds to a probability value, and is represented by a straight line with a circle, the probability threshold pth is 2%, and the probability values higher than the probability threshold pth totally include 10 values, that is, M ═ 10, the 10 probability values are divided into four groups in total according to a principle of proximity to the values, as shown in fig. 4a by identification "group 1" to "group 4", where "group 1" includes 4 probability values, "group 2" includes 1 probability value, "group 3" includes 2 probability values, and group 4 "includes 3 probability values, the interference power adjustment values corresponding to each group of probability values are averaged, so as to obtain α 1 to α 4.
Fig. 4b is a schematic diagram of probability distribution of the interference power adjustment values in an embodiment of the present invention, where L is 8, the probability distribution in fig. 4b is the same as that in fig. 4a, and 10 probability values higher than the probability threshold pth are divided into eight groups, as shown in "group 1" to "group 8" in fig. 4b, where "group 2" and "group 7" each include 2 probability values, and the other groups each include 1 probability value, and the interference power adjustment values corresponding to each group of probability values are averaged, so as to obtain α 1 to α 8.
Step 302, receiving the first downlink data sent at the first time, and estimating a first SINR according to the first downlink data.
Step 303, estimating a second SINR according to the received second downlink data, and obtaining a first power allocated to the first UE and a second power allocated to the second UE when the base station sends the second downlink data.
For example, a second UE is paired with a first UE, and the base station informs β the first UE of the first power allocated to the first UE1And a second power β allocated to the second UE2。
Step 304, a CQI adjustment factor is calculated according to the first SINR and the second SINR.
According to the first SINR1A second SINR2First power β1And a second power β2Calculating an interference power adjustment value lambda, determining the difference between the interference power adjustment value lambda and each alternative CQI adjustment value α 1, … and α L, and taking the alternative CQI adjustment value corresponding to the minimum difference in the determined differences as a CQI adjustment factor.
In an embodiment, the first UE is paired with a second UE, and the first UE determines whether the spatial resource allocated to the first UE and the spatial resource allocated to the second UE by the base station are the same according to the downlink control signaling. And judging whether the first UE and the second UE carry out orthogonal MU-MIMO transmission or non-orthogonal NOMA transmission according to whether the space resources are the same.
Specifically, if the first UE determines that the spatial resources allocated to the first UE and the spatial resources allocated to the second UE by the base station are different, and if the orthogonal resources are used to implement MU-MIMO transmission, the following equation is used
And calculating an interference power adjustment value lambda.
If the first UE determines that the spatial resources allocated to the first UE and the spatial resources allocated to the second UE by the base station are the same, for example, the NOMA transmission is implemented by using non-orthogonal resources, and the first power is β1Greater than or equal to the second power β2When the first UE is a distant user with respect to the second UE, the following equation is followed
And calculating an interference power adjustment value lambda.
For NOMA transmission, if the first power is β1Less than second power β2That is, the first UE is a close-range user with respect to the second UE, the CQI adjustment factor does not need to be fed back, and at this time, the information field for feeding back the interference power adjustment value λ in the uplink resource may be nulled.
Note that the second UE may include at least one UE. paired with the first UE and using orthogonal resources (e.g., different spatial resources) as shown in FIG. 2. if the first UE is UE1, the second UE may be UE3, or the second UE includes UE3 and UE 4. when the second UE includes multiple paired UEs, the second power β2Is the sum of the powers allocated to all paired UEs.
In another embodiment, the second UE includes a third UE and a fourth UE, the second power includes a third power β allocated to the third UE3And a fourth power β allocated to the fourth UE4. The first UE, the third UE, and the fourth UE simultaneously implement orthogonal MU-MIMO transmission and non-orthogonal NOMA transmission. At this time, the first UE determines that the space resource allocated to the first UE by the base station is different from the space resource allocated to the third UE according to the downlink control signaling, namely, MU-MIMO transmission is realized between the first UE and the third UE; base ofThe spatial resources allocated to the first UE and the spatial resources allocated to the fourth UE by the station are the same, that is, NOMA transmission is realized between the first UE and the fourth UE.
As shown in FIG. 2, if the first UE is UE1, the third UE may be UE3, or the third UE includes UE3 and UE4, and the fourth UE may be UE2 when the third UE includes multiple UEs, the third power β3Is the sum of the power allocated to all paired UEs that use different spatial resources, e.g., the sum of the power allocated to UE3 and UE4 when the fourth UE includes multiple UEs, the fourth power β4Is the sum of the powers allocated to all paired UEs using the same spatial resource.
When the first power β1Greater than fourth power β4When the first UE is a distant user compared to the fourth UE, the following equation is used
And calculating an interference power adjustment value lambda.
When the first power β1Less than or equal to fourth power β4When the first UE is a close-range user compared to the fourth UE, such as the UE1 is a close-range user compared to the UE2 in FIG. 2, the following equation is satisfied
And calculating an interference power adjustment value lambda.
Step 305, feeding back the CQI adjustment factor to the base station.
In this step, whether the UE feeds back the CQI adjustment factor to the base station may be configured semi-statically through a higher layer signaling (e.g., a radio resource control RRC signaling), or dynamically configured through a downlink control signaling by the base station.
When knowing that feedback is needed through the received signaling, the first UE may feed back the CQI adjustment factor to the base station on a Physical Uplink Control Channel (PUCCH) or a Physical Uplink Shared Channel (PUSCH).
Fig. 5 is a signaling diagram of a method for adjusting CQI in an embodiment of the present invention. Referring to fig. 5, the method comprises the following steps:
step 501, a base station sends a downlink reference signal to a first UE at a first time.
Step 502, the first UE estimates a first SINR and a first CQI according to the received downlink reference signal.
Step 503, the first UE feeds back the first CQI to the base station.
Step 504, the base station schedules the user according to the received first CQI, and when the first UE is scheduled, determines a first MCS used by the first UE according to the first CQI.
And 505, the base station schedules the first UE again, sends second downlink data to the first UE at the second time according to the first MCS, and notifies the first UE of feeding back the CQI adjustment factor through the downlink control signaling.
For example, the base station configures an indicator bit in a Physical Downlink Control Channel (PDCCH). And after receiving the indication bit, the UE knows whether the CQI adjustment factor needs to be fed back or not according to the indication bit. The configuration may be dynamic configuration, and the UE performs the calculation of the CQI adjustment factor after receiving the indicator bit. For example, the base station may count a block error rate (BLER) according to a result of a downlink hybrid automatic repeat request (HARQ), and configure an indicator bit in the PDCCH when the BLER is greater than a preset threshold.
Step 506, the first UE estimates a second SINR and a second CQI according to the received second downlink data, and calculates a CQI adjustment factor according to the first SINR and the second SINR.
In step 507, the first UE feeds back the second CQI and the CQI adjustment factor to the base station.
Step 508, the base station determines a second MCS used for subsequently transmitting the downlink data of the first UE according to the received second CQI and the CQI adjustment factor.
In step 509, the base station schedules the first UE again, encodes and adjusts the data of the first UE according to the second MCS, and transmits the third downlink data to the first UE at the third time.
The method for determining the MCS according to the SINR or the CQI may refer to an algorithm in the LTE/LTE-a protocol, which is not described herein again.
Fig. 6 is a flowchart illustrating a method for adjusting CQI according to another embodiment of the present invention. The method is applied to a base station, see fig. 6, and comprises the following steps:
step 601, sending first downlink data to the first UE at a first time so that the first UE estimates a first SINR according to the first downlink data.
In this step, the first UE may simultaneously estimate the first CQI according to the first downlink data, so as to feed the first CQI back to the base station for determining the first MCS used when transmitting the second downlink data in step 602.
Step 602, sending second downlink data to the first UE at a second time, so that the first UE estimates a second SINR according to the second downlink data, and calculates a channel quality indicator CQI adjustment factor according to the first SINR and the second SINR.
In this step, the first UE may simultaneously estimate a second CQI according to the second downlink data, so as to feed the second CQI back to the base station for determining a second MCS used when the third downlink data is transmitted in step 604.
Step 603, receiving the CQI adjustment factor fed back by the first UE.
Step 604, determining a second MCS used for transmitting the third downlink data to the first UE according to the CQI adjustment factor.
In this step, the base station allocates β the first power to the first UE according to the transmission of the second downlink data1A second power β allocated to the second UE2And the CQI adjustment factor gamma calculates a third SINR (expressed as SINR)3) Then, a second MCS used for the third downlink data is determined according to the third SINR. And the third downlink data is sent out at a third moment after the second moment.
In an embodiment, when the base station schedules the first UE and the second UE as paired users again, the base station allocates spatial resources to the first UE and the second UE. If the spatial resource allocated to the first UE is different from the spatial resource allocated to the second UE, if the MU-MIMO transmission is implemented by using orthogonal resources, calculating a third SINR according to the following equation:
if the spatial resources allocated to the first UE and the spatial resources allocated to the second UE are the same, for example, the NOMA transmission is implemented by using the non-orthogonal resources, and the first power is β1Greater than or equal to the second power β2If the first UE is a distant user with respect to the second UE, calculating a third SINR according to the following equation:
it is noted that for NOMA transmission, if the first power β is1Less than second power β2I.e. firstThe UE is a close range user with respect to the second UE, and the base station may determine a third SINR according to the second CQI fed back by the user (as described in step 602).
In another embodiment, when the base station schedules the first UE, the third UE and the fourth UE again as paired users, spatial resources are allocated to the first UE, the third UE and the fourth UE, and orthogonal MU-MIMO transmission and non-orthogonal NOMA transmission are simultaneously achieved. If the space resource allocated to the first UE and the space resource allocated to the third UE by the base station are different, MU-MIMO transmission is realized between the first UE and the third UE; the spatial resource allocated to the first UE by the base station is the same as the spatial resource allocated to the fourth UE, that is, NOMA transmission is realized between the first UE and the fourth UE. When the first power is greater than the fourth power, which means that the first UE is a distant user compared to the fourth UE, a third SINR is calculated according to the following equation:
when the first power is less than or equal to the fourth power, which represents that the first UE is a close-range user compared to the fourth UE, such as the UE1 is a close-range user compared to the UE2 in fig. 2, a third SINR is calculated according to the following equation:
wherein gamma is CQI adjustment factor and SINR1Is the first SINR, SINR2Is a second SINR, &lTtT translation = &β "&gTt β &lTt/T &gTt = &1At a first power, β3At a third power of β4Is the fourth power and N is the noise power.
When the first UE feeds back a second CQI (denoted as CQI) to the base station as described in step 6022) In the above equations (8) to (11), the noise power N is 1/CQI2。
Fig. 7 is a schematic structural diagram of a user terminal 700 in an embodiment of the present application, including:
a receiving module 710, configured to receive a first downlink signal sent at a first time and a second downlink signal sent at a second time, where the second time is after the first time;
an estimating module 720, configured to estimate a first channel quality value (e.g., SINR) according to the first downlink data received by the receiving module 710, and estimate a second channel quality value when the base station performs multi-user transmission according to the second downlink data;
a calculating module 730, configured to calculate a channel quality adjustment factor according to the first channel quality value and the second channel quality value obtained by the estimating module 720; and
a feedback module 740, configured to feed back the channel quality adjustment factor to the base station.
In an embodiment, the user terminal 700 further includes a setting module 750 configured to preset a plurality of candidate adjustment values.
Accordingly, the receiving module 710 is further configured to: and obtaining a first power distributed to the UE and a second power distributed to the second UE for multi-user transmission when the base station sends a second downlink signal by receiving the downlink control signaling.
In one embodiment, the calculation module 730 is configured to: calculating an interference power adjustment value according to the first channel quality value, the second channel quality value, the first power and the second power obtained by the receiving module 710; the difference between the interference power adjustment value and each alternative adjustment value set by the setting module 750 is determined, and the alternative adjustment value corresponding to the smallest difference in the determined differences is used as the channel quality adjustment factor.
In one embodiment, the setup module 750 is configured to: counting the probability distribution of the interference power adjustment values calculated before the second moment, and determining a probability value corresponding to each interference power adjustment value according to the probability distribution; and grouping the probability values, averaging the interference power adjustment values corresponding to the probability values in each group, and determining the obtained average value as an alternative adjustment value.
In one embodiment, the estimation module 720 is configured to: obtaining parameters of multi-user transmission from the second downlink signal, and estimating the second channel quality value by using the parameters of the multi-user transmission, where the parameters of the multi-user transmission include: a power and precoding matrix allocated to the first UE, and a power allocated to at least one second UE of the plurality of UEs.
In an embodiment, the receiving module 710 is further configured to: receiving Radio Resource Control (RRC) signaling;
the feedback module 740 is further configured to: the channel quality adjustment factor is fed back to the base station in response to the RRC signaling received by the receiving module 710.
In one embodiment, the feedback module 740 is configured to: and feeding back the channel quality adjustment factor to the base station on a physical uplink control channel PUCCH or a physical uplink shared channel PUSCH.
Fig. 8 is a schematic structural diagram of a base station 800 in an embodiment of the present invention, including:
a transmitting module 810, configured to transmit a first downlink signal at a first time, so that a first user equipment UE estimates a first channel quality value according to the first downlink signal; sending a second downlink signal at a second moment so that the first UE estimates a second channel quality value when the base station performs multi-user transmission according to the second downlink signal, and calculating a channel quality adjustment factor according to the first channel quality value and the second channel quality value;
a receiving module 820, configured to receive a channel quality adjustment factor fed back by a first UE;
a scheduling module 830, configured to determine, according to the channel quality adjustment factor received by the receiving module 820, a modulation and coding scheme MCS used by the downlink signal of the first UE.
In an embodiment, the second downlink signal may include: a power and precoding matrix allocated to the first UE for multi-user transmission, and a power allocated to at least one second UE of the plurality of UEs for multi-user transmission.
In one embodiment, the scheduling module 830 is configured to: and calculating a third channel quality value (such as SINR) according to the first power distributed to the first UE, the second power distributed to the second UE and the channel quality adjustment factor when the second downlink signal is transmitted, and determining the MCS used by the third downlink signal according to the third channel quality value, wherein the third downlink signal is transmitted at a third time after the second time.
In one embodiment, the scheduling module 830 is configured to: allocating space resources to a first UE and a second UE; if the spatial resource allocated to the first UE is different from the spatial resource allocated to the second UE, calculating a third channel quality value; if the space resource allocated to the first UE is the same as the space resource allocated to the second UE, and the first power is greater than or equal to the second power, then calculating the third channel qualityWherein gamma is a channel quality adjustment factor, β1At a first power, β2Is the second power, and N is the noise power.
In an embodiment, the second UE includes a third UE and a fourth UE, and the second power includes a third power allocated to the third UE and a fourth power allocated to the fourth UE;
the scheduling module 830 is configured to allocate spatial resources to the first UE, the third UE and the fourth UE, where the spatial resources allocated to the first UE and the spatial resources allocated to the third UE are different, and the spatial resources allocated to the first UE and the spatial resources allocated to the fourth UE by the base station are the same, calculate a third channel quality value when the first power is greater than the fourth power, and calculate the third channel quality value when the first power is less than or equal to the fourth power, where γ is a channel quality adjustment factor, β1At a first power, β3At a third power of β4Is the fourth power and N is the noise power.
In an embodiment, the base station 800 further comprises:
the control module 840 is configured to count a block error rate according to the downlink hybrid automatic repeat request result, and send a control instruction to the sending module 810 when the block error rate is greater than a preset threshold;
accordingly, the sending module 810 is further configured to: and sending a downlink control signaling to inform the UE of feeding back the channel quality adjustment factor according to the control instruction.
According to the method for feeding back the channel quality provided by the embodiment of the invention, the channel quality adjusting factor is calculated by the UE and fed back to the base station, so that the base station can obtain the channel quality deviation estimated by the UE during multi-user transmission. Furthermore, the base station can determine the MCS used when the downlink signal is really transmitted according to the channel quality adjustment factor, thereby effectively improving the accuracy of the MCS in the subsequent transmission and improving the accuracy of downlink scheduling. .
It should be noted that not all steps and modules in the above flows and structures are necessary, and some steps or modules may be omitted according to actual needs. The execution order of the steps is not fixed and can be adjusted as required. The division of each module is only for convenience of describing adopted functional division, and in actual implementation, one module may be divided into multiple modules, and the functions of multiple modules may also be implemented by the same module, and these modules may be located in the same device or in different devices. In addition, the use of "first" and "second" in the above description is merely for convenience of distinguishing two objects having the same meaning, and does not indicate substantial differences.
The modules in the various examples may be implemented in hardware or a hardware platform plus software.
The hardware may be implemented by specialized hardware or hardware executing machine-readable instructions. For example, the hardware may be specially designed permanent circuits or logic devices (e.g., special purpose processors, such as FPGAs or ASICs) for performing the specified operations. Hardware may also include programmable logic devices or circuits temporarily configured by software (e.g., including a general purpose processor or other programmable processor) to perform certain operations.
The software includes machine-readable instructions stored in a non-volatile storage medium. Thus, embodiments may also be embodied as software products. The machine-readable instructions may cause an operating system or the like operating on the computer to perform some or all of the operations described herein. The nonvolatile computer-readable storage medium may be a memory provided in an expansion board inserted into the computer or written to a memory provided in an expansion unit connected to the computer. A CPU or the like mounted on the expansion board or the expansion unit may perform part or all of the actual operations according to the instructions.
The nonvolatile computer readable storage medium includes a floppy disk, a hard disk, a magneto-optical disk, an optical disk (e.g., CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD + RW), a magnetic tape, a nonvolatile memory card, and a ROM. Alternatively, the program code may be downloaded from a server computer via a communications network.
In view of the above, the scope of the claims should not be limited to the embodiments in the examples described above, but should be given the broadest interpretation given the description as a whole.

Claims (20)

  1. A method for feeding back channel quality, which is applied to a first User Equipment (UE), comprises:
    receiving a first downlink signal sent out at a first moment, and estimating a first channel quality value according to the first downlink signal;
    receiving a second downlink signal sent at a second time after the first time, and estimating a second channel quality value when the base station performs multi-user transmission according to the second downlink signal, wherein the multi-user transmission is downlink transmission performed by the base station to a plurality of UEs including the first UE by using the same time-frequency resource;
    calculating a channel quality adjustment factor based on the first channel quality value and the second channel quality value;
    and feeding back the channel quality adjustment factor to a base station, so that the base station adjusts the channel quality of the first UE during multi-user transmission estimated by the base station according to the channel quality adjustment factor and performs multi-user transmission by using the adjusted channel quality.
  2. The method of claim 1, further comprising:
    presetting a plurality of alternative adjustment values;
    obtaining a first power allocated to the first UE and a second power allocated to a second UE when the base station transmits the second downlink signal;
    said calculating a channel quality adjustment factor based on said first channel quality value and said second channel quality value comprises:
    calculating an interference power adjustment value according to the first channel quality value, the second channel quality value, the first power and the second power;
    and determining the difference between the interference power adjustment value and each alternative adjustment value, and taking the alternative adjustment value corresponding to the minimum difference in the determined differences as the channel quality adjustment factor.
  3. The method of claim 2, wherein presetting the plurality of alternative adjustment values comprises:
    counting the probability distribution of the interference power adjustment values calculated before the second moment, and determining a probability value corresponding to each interference power adjustment value according to the probability distribution;
    grouping the probability values, averaging interference power adjustment values corresponding to the probability values in each group, and determining the obtained average value as the alternative adjustment value.
  4. The method of claim 2, wherein calculating an interference power adjustment value based on the first channel quality value, the second channel quality value, the first power, and the second power comprises:
    determining whether the space resource allocated to the first UE and the space resource allocated to the second UE by the base station are the same according to the downlink control signaling;
    if the spatial resource allocated to the first UE by the base station is different from the spatial resource allocated to the second UE, calculating the interference power adjustment value lambda;
    if the spatial resource allocated to the first UE by the base station is the same as the spatial resource allocated to the second UE and the first power is greater than or equal to the second power, calculating the interference power adjustment value lambda;
    wherein, the SINR1For the first channel quality value, SINR2For said second channel quality value, β1β for the first power2Is the second power.
  5. The method of claim 2, wherein the second UE comprises a third UE and a fourth UE, and wherein the second power comprises a third power allocated to the third UE and a fourth power allocated to the fourth UE;
    said calculating an interference power adjustment value based on said first channel quality value, said second channel quality value, said first power and said second power comprises:
    determining that the spatial resource allocated to the first UE by the base station is different from the spatial resource allocated to the third UE according to the downlink control signaling, wherein the spatial resource allocated to the first UE by the base station is the same as the spatial resource allocated to the fourth UE;
    when the first power is larger than the fourth power, the interference power adjustment value lambda is calculated;
    when the first power is less than or equal to the fourth power, adjusting a value lambda according to the calculated interference power;
    wherein, the SINR1For the first channel quality value, SINR2For said second channel quality value, β1β for the first power3At said third power, β4Is the fourth power.
  6. The method of claim 1, wherein estimating a second channel quality value for the multi-user transmission by the base station based on the second downlink signal comprises:
    and obtaining parameters of multi-user transmission from the second downlink signal, and estimating the second channel quality value by using the parameters of the multi-user transmission.
  7. The method of claim 6, wherein the parameters of the multi-user transmission comprise: a power and precoding matrix allocated to the first UE, and a power allocated to at least one second UE of the plurality of UEs.
  8. The method of any one of claims 1 to 7, further comprising: and informing the first UE to feed back the adjustment factor to the base station through Radio Resource Control (RRC) signaling.
  9. A User Equipment (UE), comprising:
    the receiving module is used for receiving a first downlink signal sent at a first moment and a second downlink signal sent at a second moment after the first moment;
    an estimating module, configured to estimate a first channel quality value according to the first downlink signal, and estimate a second channel quality value when the base station performs multi-user transmission according to the second downlink signal, where the multi-user transmission is downlink transmission performed by the base station to multiple UEs including the first UE using the same time-frequency resource;
    a calculation module for calculating a channel quality adjustment factor based on the first channel quality value and the second channel quality value; and
    and the feedback module is used for feeding the channel quality adjusting factor back to the base station, so that the base station adjusts the channel quality of the first UE during multi-user transmission estimated by the base station according to the channel quality adjusting factor and performs multi-user transmission by using the adjusted channel quality.
  10. The UE of claim 9, further comprising:
    the setting module is used for presetting a plurality of alternative adjustment values;
    the receiving module is further configured to: obtaining a first power distributed to the UE and a second power distributed to a second UE when the base station sends the second downlink signal by receiving a downlink control signaling;
    the calculation module is configured to: calculating an interference power adjustment value according to the first channel quality value, the second channel quality value, the first power and the second power; and determining the difference between the interference power adjustment value and each alternative adjustment value, and taking the alternative adjustment value corresponding to the minimum difference in the determined differences as the adjustment factor.
  11. The UE of claim 10, wherein the setup module is configured to: counting the probability distribution of the interference power adjustment values calculated before the second moment, and determining a probability value corresponding to each interference power adjustment value according to the probability distribution; grouping the probability values, averaging interference power adjustment values corresponding to the probability values in each group, and determining the obtained average value as the alternative adjustment value.
  12. The UE of claim 10,
    the estimation module is to: obtaining parameters of multi-user transmission from the second downlink signal, and estimating the second channel quality value by using the parameters of the multi-user transmission, where the parameters of the multi-user transmission include: a power and precoding matrix allocated to the first UE, and a power allocated to at least one second UE of the plurality of UEs.
  13. The UE of any of claims 9 to 12, wherein the receiving module is further configured to: receiving Radio Resource Control (RRC) signaling;
    the feedback module is further to: and feeding back the channel quality adjustment factor to the base station in response to the RRC signaling received by the receiving module.
  14. The UE of any of claims 9 to 12, wherein the feedback module is configured to: and feeding back the channel quality adjustment factor to the base station on a Physical Uplink Control Channel (PUCCH) or a Physical Uplink Shared Channel (PUSCH).
  15. A base station, comprising:
    a sending module, configured to send a first downlink signal at a first time, so that a first user equipment UE estimates a first signal to interference plus noise ratio channel quality value according to the first downlink signal; sending a second downlink signal at a second time after the first time, so that the first UE estimates a second channel quality value when the base station performs multi-user transmission according to the second downlink signal, and calculates a channel quality indication channel quality adjustment factor according to the first channel quality value and the second channel quality value, wherein the multi-user transmission is downlink transmission performed by the base station to a plurality of UEs including the first UE by using the same time-frequency resource;
    a receiving module, configured to receive the channel quality adjustment factor fed back by the first UE;
    and the scheduling module is used for determining a Modulation and Coding Scheme (MCS) used by the downlink signal of the first UE when multi-user transmission is carried out according to the channel quality adjustment factor.
  16. The base station of claim 15, wherein the scheduling module is configured to: and calculating a third channel quality value according to the first power distributed to the first UE, the second power distributed to the second UE and the channel quality adjustment factor when the second downlink signal is sent, and determining the MCS used by a third downlink signal according to the third channel quality value, wherein the third downlink signal is sent at a third time after the second time.
  17. The base station of claim 16, wherein the scheduling module is configured to allocate spatial resources to the first UE and the second UE, calculate the third channel quality value if the spatial resources allocated to the first UE and the spatial resources allocated to the second UE are different, calculate the third channel quality value if the spatial resources allocated to the first UE and the spatial resources allocated to the second UE are the same, and the first power is greater than or equal to the second power, wherein γ is the CQI adjustment factor β1β for the first power2And N is the noise power.
  18. The base station of claim 16, wherein the second UE comprises a third UE and a fourth UE, and wherein the second power comprises a third power allocated to the third UE and a fourth power allocated to the fourth UE;
    the scheduling module is to: allocating spatial resources to the first UE, the third UE and the fourth UE, wherein the spatial resources allocated to the first UE and the spatial resources allocated to the fourth UE are the sameThe spatial resources of the third UE are different, the spatial resources allocated to the first UE and the spatial resources allocated to the fourth UE by the base station are the same, when the first power is higher than the fourth power, the third channel quality value is calculated, when the first power is lower than or equal to the fourth power, the third channel quality value is calculated, wherein gamma is the channel quality adjustment factor β1β for the first power3At said third power, β4And N is the noise power.
  19. The base station of claim 15, wherein the second downlink signal comprises: a power and precoding matrix allocated to the first UE, and a power allocated to at least one second UE of the plurality of UEs.
  20. The base station according to any of claims 15 to 19, further comprising:
    the control module is used for counting the block error rate according to the result of the downlink hybrid automatic repeat request and sending a control instruction to the sending module when the block error rate is greater than a preset threshold;
    the sending module is further configured to: and sending a downlink control signaling according to the control instruction to inform the UE to feed back the channel quality adjustment factor.
CN201780008149.6A 2016-03-10 2017-03-01 A kind of method of feedback channel quality, user equipment and base station Pending CN108702738A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112039639A (en) * 2019-06-04 2020-12-04 华为技术有限公司 Feedback indication method and communication device

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110648518B (en) * 2019-09-23 2021-04-20 湖南长城信息金融设备有限责任公司 Data transmission method for unmanned aerial vehicle and remote controller and corresponding device thereof
CN113810085A (en) * 2020-06-15 2021-12-17 中兴通讯股份有限公司 Data transmission method, device, communication node and storage medium
CN112383367B (en) * 2020-11-16 2022-05-20 杭州电子科技大学上虞科学与工程研究院有限公司 MCS (modulation and coding scheme) selection method and device for simultaneous co-frequency full duplex system
CN115706608A (en) * 2021-08-13 2023-02-17 华为技术有限公司 Communication method and communication device

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100938088B1 (en) * 2006-11-01 2010-01-21 삼성전자주식회사 Method and apparatus for tranceiving feedback information in wireless packet data communication system
CN101291526B (en) * 2007-04-18 2012-10-17 松下电器产业株式会社 Adaptive scheduling method and apparatus reducing information feedback amount
JP5316547B2 (en) * 2009-01-14 2013-10-16 富士通株式会社 apparatus
CN101841356B (en) * 2009-03-18 2012-12-26 电信科学技术研究院 Method, device and system for feeding back channel quality information
CN101877887B (en) * 2009-04-30 2012-12-05 中国移动通信集团公司 Downlink transmission control method and device of cooperative multicast system
JP2011004212A (en) * 2009-06-19 2011-01-06 Sharp Corp Transmission apparatus, reception apparatus, communication system, and communication method
CN101789849B (en) * 2010-01-08 2015-06-03 中兴通讯股份有限公司 Feedback transmission method of channel state information and user equipment
JP5993238B2 (en) * 2012-07-25 2016-09-14 株式会社Ｎｔｔドコモ COMMUNICATION SYSTEM, BASE STATION DEVICE, TERMINAL DEVICE, AND COMMUNICATION METHOD
JP6429493B2 (en) * 2014-05-16 2018-11-28 株式会社Ｎｔｔドコモ Base station and modulation and coding scheme determination method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112039639A (en) * 2019-06-04 2020-12-04 华为技术有限公司 Feedback indication method and communication device

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