CN105830376A - Adaptive modulation and coding method and apparatus - Google Patents

Adaptive modulation and coding method and apparatus Download PDF

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Publication number
CN105830376A
CN105830376A CN201480036325.3A CN201480036325A CN105830376A CN 105830376 A CN105830376 A CN 105830376A CN 201480036325 A CN201480036325 A CN 201480036325A CN 105830376 A CN105830376 A CN 105830376A
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cell
base station
tti
information
scheduling information
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CN105830376B (en
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唐志华
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Huawei Technologies Co Ltd
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Huawei Technologies Co Ltd
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received

Abstract

Provided are an adaptive modulation and coding method and apparatus, which relate to the field of wireless, and can improve the accuracy of MCS selection, thereby improving system throughput. At a TTI N-T, a first base station determines scheduling information about a first user equipment (UE) of a first cell at a TTI N; at the TTI N, the first base station acquires scheduling information about a second UE of a second cell; according to measurement information about the first UE, the scheduling information about the first UE, measurement information about the second UE in the first cell and the scheduling information about the second UE, the first base station acquires an SINR prediction value of the first UE; the first base station obtains an SINR value of the first UE according to the SINR prediction value and an SINR adjustment amount; and according to a correlation between an SINR and a modulation and coding scheme (MCS), the first base station determines the MCS corresponding to the SINR value of the first UE. The adaptive modulation and coding method and apparatus are used for adaptive modulation and coding.

Description

Adaptive modulation and coding method and device Technical Field
The present invention relates to the wireless field, and in particular, to a method and an apparatus for adaptive modulation and coding.
Background
An Adaptive Modulation and Coding (AMC) technique is an Adaptive technique that adaptively selects a Modulation and Coding Scheme (MCS) according to a wireless channel state on the premise of ensuring the reliability of a wireless communication system, so as to improve the throughput of the wireless communication system.
Taking a Long Term Evolution (LTE) system as an example, in the prior art, after an evolved NodeB (eNB) receives a Reference Signal sent by a User Equipment (UE), such as a channel Sounding Reference Signal (SRS) or a Demodulation Reference Signal (DMRS), an uplink Signal to Interference plus Noise Ratio (SINR) is measured according to the Reference Signal, and the SINR is subjected to smoothing filtering to obtain an uplink SINR smoothed value; when the UE is scheduled, the base station takes the uplink SINR smoothing filtering value as an SINR predicted value when the UE performs actual data Transmission after a plurality of Transmission Time Intervals (TTIs), corrects the SINR predicted value by using an SINR adjustment amount to obtain an SINR value, and acquires an MCS required to be adopted by output according to the SINR value and the corresponding relation between the uplink SINR and the uplink MCS.
However, due to the non-persistence of the UE service, the data transmission of the UE is not continuous in the time domain, but often varies in the frequency domain, so that the neighboring cell interference suffered by the UE varies very severely, and there is no correlation in the time domain. In order to solve the problem that MCS selection is inaccurate, a base station can acquire adjacent cell interference through interaction between base stations, but the base station cannot acquire the adjacent cell interference in time and cannot accurately select the MCS by using real-time interference information due to non-ideal return in an actual wireless network system. Therefore, in a non-ideal backhaul scenario, it is an urgent problem to improve the accuracy of MCS selection and the system throughput by using the neighboring cell interference information.
Disclosure of Invention
The embodiment of the invention provides a method and a device for adaptive modulation and coding, which can improve the accuracy of MCS selection and further improve the system throughput rate.
In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:
in a first aspect, a method for adaptive modulation and coding is provided, including:
in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
in the TTI N, the first base station acquires scheduling information of second UE of a second cell, the second cell belongs to a second base station, the scheduling information of the second UE is the scheduling information of the second UE in the TTI N, and the scheduling information of the second UE is the scheduling information which is determined by the second base station in the TTI N-T and is sent to the first base station;
when the resource block of the first UE is the same as the resource block of the second UE, the first base station acquires the measurement information of the first UE in the first cell and the measurement information of the second UE in the first cell;
according to the measurement information of the first UE, the scheduling information of the first UE, the measurement information of the second UE in a first cell and the scheduling information of the second UE, the first base station obtains a signal to interference plus noise ratio (SINR) predicted value of the first UE;
the first base station obtains an SINR value of the first UE according to the SINR predicted value and the SINR adjustment amount;
and the first base station determines the MCS corresponding to the SINR value of the first UE according to the corresponding relation between the SINR and the modulation and coding scheme MCS.
With reference to the first aspect, in a first implementable manner, after the determining, by the first base station, the scheduling information of the first user equipment UE of the first cell in the transmission time interval TTI N-T in the first implementable manner, the method further includes:
in TTI N-S, the first base station acquires retransmission information of a third UE in the first cell, wherein the retransmission information comprises feedback information that the third UE needs to retransmit in TTI N, S is smaller than T, and T is the time delay of the first cell of the first base station acquiring scheduling information of a second UE of the second cell;
and in the TTI N, the first base station determines that the third UE is not scheduled in the TTI N-T, and delays the third UE for scheduling by one scheduling period.
With reference to the first implementable manner, in a second implementable manner, the delaying the third UE by one scheduling cycle scheduling includes:
when the scheduling period is 8 TTIs, in TTI N +8-T, the first base station determines scheduling information of a third UE of the first cell in TTI N +8, and in TTI N +8, the first base station sends an uplink Grant (UL Grant) to the third UE, wherein new data in the UL Grant indicates that the NDI is not inverted, so that the third UE performs retransmission in a self-adaptive retransmission mode.
With reference to the first aspect, in a third implementation manner, the method according to claim 1, wherein the method further includes:
in TTI N-S, the first base station acquires retransmission information of a third UE in the first cell, wherein the retransmission information comprises feedback information which needs to be retransmitted by the third UE in TTI N;
in the TTI N-T, the first base station determines the scheduling information of the third UE of the first cell in the TTI N, and the T is the time delay of the first cell of the first base station for acquiring the scheduling information of the second UE of the second cell;
after the first base station acquires scheduling information of a second UE of a second cell, the method further includes:
and in the TTI N, the first base station sends an uplink Grant (ULGrant) to the third UE, wherein new data in the UL Grant indicates that the NDI is not inverted, so that the third UE performs retransmission in a self-adaptive retransmission mode.
In a second aspect, a method for adaptive modulation and coding is provided, including:
in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
in TTI N-S, the first base station acquires retransmission information of the first UE in the first cell, wherein the retransmission information comprises feedback information that the first UE needs to retransmit in TTI N;
and in the TTI N, the first base station sends an uplink Grant (ULGrant) to the first UE, wherein new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in a self-adaptive retransmission mode.
In a third aspect, a base station is provided, including:
a processing unit, configured to determine, at a transmission time interval TTI N-T, scheduling information of a first user equipment UE of a first cell at TTI N, where the scheduling information includes a resource block and a transmission power allocated to the first UE, and where, at the TTI N, the first base station schedules the first UE, and the first cell belongs to the first base station;
an obtaining unit, configured to obtain, at the TTI N, scheduling information of a second UE of a second cell by the first base station, where the second cell belongs to a second base station, the scheduling information of the second UE is scheduling information of the second UE at the TTI N, and the scheduling information of the second UE is scheduling information determined by the second base station at the TTI N-T and sent to the first base station;
the obtaining unit is further configured to, when the resource block of the first UE is the same as the resource block of the second UE, obtain, by the first base station, measurement information of the first UE in the first cell and measurement information of the second UE in the first cell;
the processing unit is further configured to, according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE, the first base station obtains a predicted value of a signal to interference plus noise ratio SINR of the first UE;
the processing unit is further configured to obtain, by the first base station, an SINR value of the first UE according to the SINR predicted value and an SINR adjustment amount;
the processing unit is further configured to determine, by the first base station, an MCS corresponding to the SINR value of the first UE according to a correspondence between the SINR and a modulation and coding scheme, MCS.
In a fourth aspect, a base station is provided, comprising:
a processing unit, configured to determine, at a transmission time interval TTI N-T, scheduling information of a first user equipment UE of a first cell at TTI N, where the scheduling information includes a resource block and a transmission power allocated to the first UE, and where, at the TTI N, the first base station schedules the first UE, and the first cell belongs to the first base station;
the processing unit is further configured to, in TTI N-S, acquire, by the first base station, retransmission information of the first UE in the first cell, where the retransmission information includes feedback information that the first UE needs to retransmit in TTI N;
a sending unit, configured to send, by the first base station, an uplink Grant UL Grant to the first UE in the TTI N, where new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in an adaptive retransmission manner.
In a fifth aspect, a base station is provided, including:
a memory for storing program code;
a processor for calling the program code stored in the memory to execute the following method: in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
a receiver, configured to, in the TTI N, obtain, by the first base station, scheduling information of a second UE of a second cell, where the second cell belongs to a second base station, the scheduling information of the second UE is scheduling information of the second UE in the TTI N, and the scheduling information of the second UE is scheduling information that is determined by the second base station in the TTI N-T and is sent to the first base station;
the processor-implemented method further comprises:
when the resource block of the first UE is the same as the resource block of the second UE, the first base station acquires the measurement information of the first UE in the first cell and the measurement information of the second UE in the first cell;
the processor is further configured to, according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE, the first base station obtains a predicted value of a signal to interference plus noise ratio SINR of the first UE;
the processor is further configured to obtain, by the first base station, an SINR value of the first UE according to the SINR predicted value and an SINR adjustment amount;
the processor is further configured to determine, by the first base station, an MCS corresponding to the SINR value of the first UE according to a correspondence between the SINR and a modulation and coding scheme, MCS.
In a sixth aspect, there is provided a base station comprising:
a memory for storing program code;
a processor for calling the program code stored in the memory to execute the following method: in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
the processor is further configured to, at TTI N-S, obtain, by the first base station, retransmission information of the first UE in the first cell, where the retransmission information includes feedback information that the first UE needs to retransmit at TTI N;
a transmitter, configured to send, by the first base station, an uplink Grant UL Grant to the first UE in the TTI N, where new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in an adaptive retransmission manner.
Compared with the prior art, the embodiment of the invention provides a method and a device for adaptive modulation and coding, wherein a first base station determines the scheduling information of a first UE of a first cell at TTIN at TTI N-T, and the first base station acquires the scheduling information of a second UE which is determined by a second cell at TTIN-T and is sent to the first base station at TTI N, so that the transmission delay of the interference factors of other user equipment to the first UE can be overcome under the non-ideal backhaul scene, the interference factors of other user equipment to the first UE are considered, the precision of the base station for calculating the SINR value of the scheduled first UE of the current cell is improved, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of a wireless communication system is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic structural diagram of an LTE communication system according to an embodiment of the present invention;
fig. 2 is a flowchart of a method for adaptive modulation and coding according to an embodiment of the present invention;
fig. 3 is a flow chart of another adaptive modulation and coding method according to an embodiment of the present invention;
fig. 4 is a flowchart of another adaptive modulation and coding method according to an embodiment of the present invention;
fig. 5 is a flowchart of another adaptive modulation and coding method according to an embodiment of the present invention;
FIG. 6 is a flow chart of another adaptive modulation and coding method according to an embodiment of the present invention;
fig. 7 is a schematic diagram of a base station according to an embodiment of the present invention;
fig. 8 is a schematic diagram of another base station according to an embodiment of the present invention;
fig. 9 is a schematic structural diagram of a base station according to another embodiment of the present invention;
fig. 10 is a schematic diagram of a base station according to another embodiment of the present invention;
fig. 11 is a schematic diagram of another base station according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiments of the present invention can be applied to various application scenarios consisting of a transmitting end and a receiving end, wherein the transmitting end is a user equipment and the receiving end is a base station during uplink transmission.
As shown in fig. 1, an LTE communication system structure diagram includes a base station a, a base station B, a user equipment 1, a user equipment 2, a user equipment 3, a user equipment 4, a user equipment 5, and a user equipment 6.
The coverage area of the base station a may be as shown by a solid circle line in fig. 1, and the dotted line shows that the coverage area is divided into a cell a1, a cell a2, and a cell A3 by the base station a, and the cell a1, the cell a2, and the cell A3 are adjacent to each other. User equipment 1, user equipment 2, user equipment 3, and user equipment 4 are registered in cell a1, and user equipment 5 is registered in cell a 2. User equipment 1, user equipment 2, user equipment 3, user equipment 4 and user equipment 5 are in wireless communication with base station a, respectively.
The coverage area of the base station B may be as shown by a solid circle in fig. 1, and the dotted line shows that the coverage area of the base station B is divided into a cell B1, a cell B2 and a cell B3, and the cell B1, the cell B2 and the cell B3 are adjacent to each other. The user equipment 6 is registered with cell B3. The user equipment 6 communicates wirelessly with the base station B.
Optionally, at least two cells of cell a1, cell a2, cell A3, cell B1, cell B2, and cell B3 form a coordinated cell set.
The embodiment of the invention provides a method for adaptive modulation and coding, which is applied to a base station, and as shown in fig. 2, the method comprises the following steps:
step 201, in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE in a first cell in TTI N.
The first UE is registered in a first cell and communicates with a base station through the first cell, the base station distributes scheduling information for the scheduled first UE, the scheduling information comprises resource blocks and transmitting power distributed by the base station for the first UE in the first cell, and the first cell belongs to the base station. And N is the time when the base station determines the scheduling information of the user equipment of the first cell. The scheduling information includes resource blocks and transmission power allocated for the user equipment.
Step 202, in the TTI N, the first base station acquires scheduling information of a second UE in a second cell.
And the second cell belongs to a second base station, the scheduling information of the second UE is the scheduling information of the second UE in the TTI N, and the scheduling information of the second UE is the scheduling information which is determined by the second base station in the TTI N-T and is sent to the first base station. It should be noted that the second base station to which the second cell belongs is different from the first base station to which the first cell belongs, and the first base station to which the first cell belongs and the second base station to which the second cell belongs may perform scheduling information interaction through an X2 interface or an S1 interface. The scheduling information of the second UE of the second cell includes resource blocks and transmission power allocated to the second UE of the second cell by the second base station to which the second cell belongs. In the method of the present invention, the second user equipment comprises at least one second cell.
The base station may acquire scheduling information of the second user equipment of the at least one second cell in at least one Transmission Time Interval (TTI).
Step 203, when the resource block of the first UE is the same as the resource block of the second UE, the first base station obtains the measurement information of the first UE in the first cell and the measurement information of the second UE in the first cell.
Step 204, according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE, the first base station obtains a predicted value of the SINR of the first UE.
Step 205, the first base station obtains the SINR value of the first UE according to the SINR predicted value and the SINR adjustment amount.
The base station counts uplink Block Error Rate (BLER), calculates SINR adjustment amount, and adjusts the SINR predicted value according to the SINR adjustment amount to obtain the SINR value of the UE. If the uplink BLER does not meet the preset BLER target value, the adjustment quantity of the adjustment period is adjusted upwards according to the preset adjustment amplitude on the basis of the adjustment quantity of the previous period; if the uplink BLER is larger than the BLER target value, the adjustment quantity of the adjustment period is adjusted downwards according to the preset adjustment amplitude on the basis of the adjustment quantity of the previous period.
Step 206, the first base station determines the MCS corresponding to the SINR value of the first UE according to the correspondence between SINR and modulation and coding scheme MCS.
And the base station schedules the initial transmission UE of the first cell by using the MCS corresponding to the SINR value of the initial transmission UE.
Compared with the prior art, the scheduling information of the first UE of the first cell in the TTI N is determined by the first base station in the TTI N-T, and the scheduling information of the second UE determined by the second cell in the TTI N-T and sent to the first base station is obtained by the first base station in the TTI N, so that the transmission delay of the interference factors of other user equipment to the first UE can be overcome under the non-ideal backhaul scene, the interference factors of other user equipment to the first UE are considered, the precision of calculating the SINR value of the scheduled first UE of the current cell by the base station is improved, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of the wireless communication system is improved.
The embodiment of the invention provides a method for adaptive modulation and coding, which is applied to a base station and comprises the following steps as shown in fig. 3:
step 301, at a transmission time interval TTI N-T, the first base station determines scheduling information of the first user equipment UE of the first cell at TTI N.
The scheduling information includes resource blocks and transmission power allocated to the first UE, wherein the first base station schedules the first UE in the TTI N, and the first cell belongs to the first base station.
Step 302, in TTI N-S, the first base station acquires retransmission information of the first UE in the first cell.
The retransmission information comprises feedback information that the first UE needs to retransmit in the TTI N. It should be noted that TTI N-S is smaller than TTI N-T, and optionally TTI N-S is larger than TTI N-T.
Step 303, in the TTI N, the first base station sends an uplink Grant UL Grant to the first UE, where new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in a self-adaptive retransmission manner.
In contrast to the prior art, the first base station determines the scheduling information of the first UE of the first cell in TTI N by, at TTI N-T, when in TTI N-S, the first base station acquires retransmission information of the first UE in the first cell, and in the TTI N, the first base station can send an uplink Grant (UL Grant) to the first UE, wherein the new data in the UL Grant indicates that the NDI is not flipped, so that the first UE retransmits in an adaptive retransmission manner, under the non-ideal backhaul scenario, the transmission delay for obtaining the interference factors of other user equipment to the first UE can be overcome, the interference factors of other user equipment to the first UE are considered, the accuracy of the base station for calculating the SINR value of the scheduled first UE of the current cell is improved, therefore, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of the wireless communication system is further improved.
An embodiment of the present invention provides a method for adaptive modulation and coding, which is applied to an LTE communication system shown in fig. 1, and as shown in fig. 4, the method includes:
step 401, in TTI N-T, base station a determines the scheduling information of user equipment 1 and user equipment 2 of cell a1 in TTI N.
The cell a1 of the base station a acquires the scheduling information of the user equipment 1 that is delayed in the previous scheduling period and the scheduling information of the user equipment 2 that needs to be initially transmitted, where the TTI N needs to perform data transmission, and shares the scheduling information of the user equipment 1 that is delayed in the previous scheduling period and the scheduling information of the user equipment 2 that needs to be initially transmitted to another cell, for example, the cell B3. The user equipment 2 is initial transmission user equipment, the base station a allocates resource blocks and transmission power to the user equipment 2 in the cell a1, and the scheduling information of the cell a1 includes the resource blocks and the transmission power allocated to the user equipment 2. It should be noted that, the T is a time delay for the cell a1 of the base station a to acquire the scheduling information of the user equipment 5 in the cell a2 and the scheduling information of the user equipment 6 in the cell B3, and the N is the time delay for the base station a to determine the scheduling information of the user equipment in the cell a 1. Generally, one scheduling period of Frequency Division Duplexing (FDD) is 8 transmission time intervals.
Step 402, in TTI N-S, base station A obtains the retransmission information of user equipment 3 in cell A1.
The retransmission information comprises feedback information that the user equipment 3 needs to retransmit in said TTI N.
Step 403, in TTI N, the base station a obtains the scheduling information of the user equipment 5 in cell a2 and the scheduling information of the user equipment 6 in cell B3.
In TTI N, cell a1 of base station a obtains scheduling information for user equipment 5 of cell a2 over the internal interface, and cell a1 of base station a obtains scheduling information for user equipment 6 of cell B3 from base station B over the X2 interface. The scheduling information of user equipment 6 of cell B3 may be the scheduling information that base station B determined and sent to base station a at the TTIs N-T. The scheduling information includes that the cell A2 of the base station A allocates resource blocks and transmission power for the user equipment 5, and the cell B3 of the base station B allocates resource blocks and transmission power for the user equipment 6. Wherein N-S is less than N.
It should be noted that other cells also obtain the scheduling information of the user equipment of the cells other than the current cell.
For example, as shown in fig. 5, the first cell, the second cell, and the third cell are cells of the same coordinated cell set, and the first cell acquires scheduling information of the second cell and the third cell, the second cell acquires scheduling information of the first cell and the third cell, and the third cell acquires scheduling information of the first cell and the second cell between the N-T TTI and the nth TTI. After each cell in the first cell, the second cell and the third cell obtains the scheduling information of the cell and the scheduling information of other cells, the first cell, the second cell and the third cell respectively carry out cooperative interference prediction to obtain an SINR predicted value.
It should be noted that the cell described in the present invention may be a cell in a coordinated cell set, where the coordinated cell set includes at least two cells, and may be statically set or dynamically set. The cells included in the cooperative cell set may also be cells of different base stations, and scheduling information is exchanged among a plurality of base stations through an optical fiber or an ethernet (e.g., an ip ran (internet protocol radio access network)), but it is necessary to ensure that the cells in the cooperative cell set are synchronized.
Step 404, the base station a determines the retransmission user equipment.
It should be noted that, in the process of an uplink Hybrid Automatic Repeat Request (HARQ), it is assumed that, in an nth subframe, a base station sends an uplink grant to a user equipment, and allocates an uplink resource to the user equipment, so that the user equipment can use the uplink resource to transmit data, the user equipment receives the uplink grant in the nth subframe, and receives initial transmission data in an n +4 th subframe, after the physical layer baseband processing portion decodes the data, the accuracy of the decoded data is checked according to a Cyclic Redundancy Check (CRC) Check value of 24 bits, and the decoding result is sent to an HARQ entity, and the HARQ entity sends feedback information to the user equipment in the n +8 subframes, and if the decoding is correct, sends an ACK, and if the decoding is incorrect, sends a NACK. The user equipment receives the feedback information of the initially transmitted data in n +8 subframes, if ACK is received, new data is transmitted in the next polling subframe, and if NACK is received, retransmitted data is transmitted in n +12 subframes.
And when S is less than T, determining the retransmission user equipment needing retransmission in the TTI according to the retransmission user equipment in the TTI N and the initial transmission user equipment acquired in the TTI N-S. Specifically, if the user equipment retransmitted in the TTI N acquired in the TTI N-S is scheduled in the TTI N-T, the user equipment retransmitted in the TTI N acquired in the TTI N-S is determined to be the user equipment retransmitted in the TTI N; and if the user equipment which is obtained in the TTI N-S and retransmitted in the TTI N is not scheduled in the TTI N-T, delaying the user equipment which is obtained in the TTIN-S and retransmitted in the TTI N for scheduling by a scheduling period.
For example, in TTI N-T, the base station a only obtains the scheduling information of the user equipment 1 and the user equipment 2 in the cell a1, but does not obtain the retransmission information of the user equipment 3 in the cell a1 in TTI N, only shares the scheduling information of the user equipment 1 and the user equipment 2 in the cell a1 to other cells, and in TTI N-S, the base station a only obtains the retransmission information of the user equipment 3 in the first cell in TTI N, so that the base station a delays the user equipment 3 for scheduling by one scheduling period.
The base station a sends an acknowledgement ACK to the user equipment 3, suspends the HARQ process of the user equipment 3, and then delays 8 TTIs (LTE uplink is synchronous HARQ) on the air interface to send an uplink scheduling indication UL Grant to schedule the user equipment 3. Because T TTIs are scheduled in advance, the scheduling of the user equipment 3 is delayed by 8-T TTIs, i.e., 8 TTIs are delayed on the air interface. The HARQ scheduling period amounts to a delay from 8 TTIs to 16 TTIs. The retransmission must send the UL Grant, wherein the new data indicates that NDI does not flip, and an adaptive retransmission scheme is adopted. In addition, when the user equipment 3 only receives ACK and does not receive ul grant, data is not retransmitted, but the variable CURRENT _ TX _ NB recording the transmission times is still accumulated, and once the CURRENT _ TX _ NB reaches the configured maximum transmission time-1, the user equipment 3 empties the HARQ buffer. To solve this problem, if the target maximum number of retransmissions is M, the maximum number of retransmissions configured to the UE needs to be 2M.
It should be noted that, if the base station a acquires the retransmission information of the user equipment 1 in the cell a1 in TTI N, and the cell a1 of the base station a acquires the scheduling information of the user equipment 1 delayed in the previous scheduling period in TTI N-T, because the user equipment 1 is scheduled in TTI N-T, the user equipment 1 is retransmitted according to the scheduling information of the user equipment 1 delayed in the previous scheduling period. Therefore, other scheduled users in the cell can not be influenced, and interference estimation of the adjacent cell can not be influenced.
Specifically, when S > T, in TTI N-S, acquiring retransmission information of the retransmission user equipment in the cell a1 in TTI N, where the retransmission information includes feedback information that the retransmission user equipment needs to retransmit in TTI N; acquiring scheduling information of initial transmission user equipment and scheduling information of retransmission user equipment in a TTI N cell A1 in a TTI N-T; and in TTI N, determining the user equipment retransmitted in TTI N acquired in TTI N-S as the retransmission user equipment needing to be retransmitted in TTI N.
For example, in TTI N-S, the base station a acquires retransmission information of the user equipment 4 in the cell a1 in TTI N, acquires scheduling information of the user equipment 2 and scheduling information of the user equipment 4 in the cell a1 in TTI N, and sends the scheduling information of the user equipment 2 and the scheduling information of the user equipment 4 to the cell a2 and the cell B3 in TTI N-T, and in TTI N, determines the user equipment 4 in TTI N acquired in TTI N-S as a retransmission user equipment that needs to be retransmitted in the TTI N. In TTI N, the base station a sends an uplink Grant UL Grant to the user equipment 4, where new data in the UL Grant indicates that NDI is not inverted, and the user equipment 4 performs adaptive retransmission according to the initially transmitted scheduling information of the user equipment 4.
It should be noted that, in general, T is 2 to 4 milliseconds, and S is 1 to 2 milliseconds.
Step 405, the base station a obtains the SINR prediction value of the user equipment 2 according to the measurement information of the user equipment 2, the scheduling information of the user equipment 2, the measurement information of the user equipment 5 in the cell a1 of the cell a2, the scheduling information of the user equipment 5, the measurement information of the user equipment 6 in the cell B3 in the cell a1, and the scheduling information of the user equipment 6.
First, after the interaction of the resource blocks and the transmission power of the user equipments in all the cells is completed, cell a1 compares each Resource Block (RB) allocated by the user equipment 2 with the received resource blocks in the user equipment 5 of cell a2 and the user equipment 6 of cell B3. If the resource block used by the user equipment 5 in cell a2 also includes the resource block allocated by the user equipment 2, the user equipment 5 is set as the interference source of the user equipment 2 in cell a1 on the resource block, and similarly, if the resource block used by the user equipment 6 in cell B3 also includes the resource block allocated by the user equipment 2, the user equipment 6 is set as the interference source of the user equipment 2 in cell a1 on the resource block.
For example, as shown in fig. 6, it is assumed that the Resource Block allocated to the second user equipment in the first cell includes an nth Resource Block (RB) 51, the Resource Block allocated to the second user equipment in the second cell also includes a Resource Block n, and the Resource Block allocated to the third user equipment in the third cell also includes a Resource Block n. Since the frequency reuse factor of the LTE communication system is 1, the user equipments occupying the same resource block use the same resource block at the same time to interfere with each other, and on the resource block n, the second user equipment in the second cell and the third user equipment in the third cell are interference sources of the second user equipment in the first cell.
It should be noted that, when the measurement information obtained from the user equipment is more, the first cell may sort all the interference sources according to the signal strength, and select the interference sources whose interference strength reaches a certain preset threshold or a preset number of interference sources.
Then, cell a1 of base station a acquires channel information from user equipment 2 to cell a1, transmission power of user equipment 2, channel information from user equipment using the same resource block as user equipment 2 to cell a1, transmission power of user equipment using the same resource block as user equipment 2, and interference noise estimation for the user equipment 2 except for the cell, and calculates the SINR prediction value, the channel information including channel response estimation.
For example, the SINR prediction value of each subcarrier of each RB allocated to the user equipment may be calculated according to formula (1.1a), and then the SINR prediction values of each subcarrier are combined into the SINR prediction value of the user equipment over the scheduling bandwidth:
wherein, γn，jFor SINR, p, on RB n sub-carrier jn，jFor the transmission power, w, of the user equipment on RB n subcarrier jn，jDetecting a weight vector, h, for a signal of a user equipment on RB n sub-carriers jn，jFor the channel response vector, R, of the user equipment on RB n sub-carriers jzz，n，jAs an interference noise covariance matrix, (.)HRepresenting a conjugate transpose.
Then, the SINRs of the subcarriers are combined into an RB-level SINR γnAnd then combined into the predicted SINR value of the user equipment, and the combining formula depends on the adopted receiver. For example, when a Minimum Mean Square Error (MMSE) receiver is used, the SINR of the subcarriers can be first combined into the SINR γ of RB level by using equation (1.2)nAnd then using the formula (1.2) to convert the SINR gamma of RB levelnAnd the SINR predicted values are combined into the SINR predicted value of the user equipment, and the formula (1.2) is as follows:
where L is the number of elements of the combining set, i.e., the number of subcarriers or the number of RBs.
Optionally, when the channel information includes reference signal received power and/or reference signal received quality, the SINR historical measurement value of each subcarrier per RB allocated to the user equipment may also be corrected based on the channel information from the user equipment 2 to the cell a1, the transmission power of the user equipment 2, the channel information from the user equipment using the same resource block as the user equipment 2 to the cell a1, the transmission power of the user equipment using the same resource block as the user equipment 2, and interference noise estimation for the user equipment 2 except for the cell, and the SINR prediction value is calculated as formula (1.1 b):
γ(t)＝γmeasure(t-s)+λ(t)·[I(t-s)-I(t)]+[P(t)-P(t-s)] (1.1b)
wherein, γmeasure(t-s) denotes the measured SINR history measure of t-s, the reference signal received power and/or reference signal received quality by user equipment 2 to cell a1, the transmit power of user equipment 2, the SINR history measure of user equipment 2, the same usage as user equipment 2The channel information from the user equipment of the resource block to the cell A1, the transmission power of the user equipment using the same resource block as the user equipment 2, and the interference noise estimation of the user equipment 2 outside the cell are obtained, I (t-s) represents the measured interference intensity information of t-s, I (t) represents the interference intensity information corresponding to t actual data transmission predicted during current scheduling, λ (t) is the current maintained SINR correction weight, and λ (t) > 0. If T-s is predicted to be higher than T (I) (T) is greater than I (T-T), the SINR predicted value is reduced, and if T-s is predicted to be lower than T, the SINR predicted value is increased. P (t) represents the predicted transmit power spectrum for t, and P (t-s) represents the predicted transmit power spectrum for t-s under test.
Then, the SINRs of the subcarriers are combined into an RB-level SINR γnAnd then combined into the predicted SINR value of the user equipment, and the combining formula depends on the adopted receiver. For example, using equation (1.2).
In the LTE communication system, channel information from the ue to multiple cells may be measured through a DeModulation Reference Signal (DMRS) or a Sounding Reference Signal (SRS) sent by the ue, where the channel information includes Reference Signal received power, Reference Signal received quality, and/or channel response estimation.
Furthermore, for the interference noise estimation of the user equipment 2 outside the cell, the estimation can be performed by tracking the historical value, so as to obtain more accurate cooperative interference prediction. In order to estimate the interference noise estimation for the user equipment 2 outside the cell, it is necessary to measure the total actually received interference noise and subtract the measured interference information of the cell. Since the scheduling information outside the cell is not available, the filtered value can be used as an estimate of the remaining interference noise outside the actual data transfer cell set. For example, interference sources outside the set of cooperating cells and background noise interfere with the user equipment 2.
And step 406, obtaining the SINR value of the user equipment 2 according to the SINR predicted value and the SINR adjustment amount adjustment.
Step 407, determining the MCS corresponding to the SINR value of the user equipment 2 according to the correspondence between the SINR and the MCS.
The base station a uses the SINR adjustment value to query the correspondence between SINR and MCS, selects the MCS that the user equipment 2 needs to use, and further, the cell a1 sends the selected MCS to the user equipment 2, so that the user equipment 2 transmits uplink data in the modulation and coding scheme represented by the MCS. It should be noted that the SINR adjustment mechanism, the corresponding relationship between SINR and MCS are exactly the same as the existing scheme. The 3GPP protocol defines 29-order modulation and coding schemes of MCS0 to MCS28, which represent different modulation schemes and channel coding rates, respectively, and selects an appropriate MCS according to different channel conditions, thereby maximizing the throughput of the wireless communication system.
Particularly, in a Coordinated Multiple Points (CoMP) scenario, the interference source is determined according to the CoMP. For example, the coordinated multipoint of the user equipment 2 is cell a1 and cell a2, then the interference source of the user equipment 2 includes not only the interfering user equipment to cell a1 but also the interfering user equipment to cell a2, and on the resource block n, the user equipment 6 is not only the interference source of the user equipment 2 in cell a1, but also the interference source of the user equipment 2 in cell a 2. CoMP coordinated multipoint transmission refers to multiple transmission points separated in geographic location, and cooperatively participate in joint reception of data sent by one terminal.
Moreover, when the cell a1 receives the data demodulation error of the user equipment 2, it needs to wait for the received data of the cooperative neighboring cell, and the received data of the cooperative neighboring cell is also delayed by T TTIs, which is equivalent to that the retransmission is extended from 8 TTIs to 8+ T TTIs.
It should be noted that, in TTI N, the user equipment 1 retransmits the resource block in the scheduling information acquired in TTI N-T.
Compared with the prior art, the adaptive modulation and coding method provided by the embodiment of the invention has the advantages that the base station A determines the scheduling information of the user equipment 2 of the cell A1 in the TTI N through the TTI N-T, and the base station A acquires the scheduling information of the user equipment of the cell A2 and the cell B3 determined and sent to the TTI-T through the TTI N, so that the transmission delay of the interference factor of the user equipment 2 of the cell A1 acquired by other user equipment can be overcome under a non-ideal backhaul scene, the interference factor of the other user equipment to the user equipment 2 is considered, the precision of calculating the SINR value of the user equipment 2 scheduled by the current cell by the base station is improved, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of a wireless communication system is further improved.
Specifically, when T is equal to 0, that is, when there may be no time delay for the cell a1 of the base station a to acquire the scheduling information of the user equipment 5 of the cell a2, and TTI N-T is TTI N, the base station a may determine the scheduling information of the user equipment 2 of the cell a1 and acquire the scheduling information of the user equipment 5 of the cell a2 at TTI N, so that when the resource block of the user equipment 2 is the same as that of the user equipment 5, the base station a acquires the measurement information of the user equipment 2 in the cell a1 and the measurement information of the user equipment 5 in the cell a 1; according to the measurement information of the user equipment 2, the scheduling information of the user equipment 2, the measurement information of the user equipment 5 in the cell A1 and the scheduling information of the user equipment 5, the base station A acquires an SINR predicted value of the user equipment 2; the base station A obtains an SINR value of the user equipment 2 according to the SINR predicted value and the SINR adjustment amount; the base station a determines the MCS corresponding to the SINR value of the user equipment 2 based on the correspondence between the SINR and the modulation and coding scheme MCS. The detailed procedure of predicting the SINR value is as described in the above embodiment. The cell a1 may belong to the same base station as the cell a2, and the base station may directly obtain the scheduling information of the user equipment 5 in the cell a 2.
An embodiment of the present invention provides a base station 50, as shown in fig. 7, including:
a processing unit 501, configured to determine, at a transmission time interval TTI N-T, scheduling information of a first user equipment UE of a first cell at TTI N, where the scheduling information includes a resource block and a transmission power allocated to the first UE, and where, at the TTI N, the first base station schedules the first UE, and the first cell belongs to the first base station;
an obtaining unit 502, configured to obtain, at the TTI N, scheduling information of a second UE of a second cell, where the second cell belongs to a second base station, the scheduling information of the second UE is scheduling information of the second UE at the TTI N, and the scheduling information of the second UE is scheduling information determined by the second base station at the TTI N-T and sent to the first base station;
the obtaining unit 502 is further configured to, when the resource block of the first UE is the same as the resource block of the second UE, obtain, by the first base station, measurement information of the first UE in the first cell and measurement information of the second UE in the first cell;
the processing unit 501 is further configured to, according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE, the first base station obtains a predicted value of a signal to interference plus noise ratio SINR of the first UE;
the processing unit 501 is further configured to obtain, by the first base station, an SINR value of the first UE according to the SINR predicted value and an SINR adjustment amount;
the processing unit 501 is further configured to determine, by the first base station, an MCS corresponding to the SINR value of the first UE according to the correspondence between the SINR and the modulation and coding scheme MCS.
Compared with the prior art, the scheduling information of the first UE of the first cell in the TTI N is determined by the first base station in the TTI N-T, and the scheduling information of the second UE determined by the second cell in the TTI N-T and sent to the first base station is obtained by the first base station in the TTI N, so that the transmission delay of the interference factors of other user equipment to the first UE can be overcome under the non-ideal backhaul scene, the interference factors of other user equipment to the first UE are considered, the precision of calculating the SINR value of the scheduled first UE of the current cell by the base station is improved, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of the wireless communication system is improved.
In an embodiment, the processing unit 501 is further configured to, in TTI N-S, obtain retransmission information of a third UE in the first cell by the first base station, where the retransmission information includes feedback information that the third UE needs to retransmit in the TTI N, and S is smaller than T, where T is a time delay for the first cell of the first base station to obtain scheduling information of a second UE of the second cell;
the processing unit 501 is further configured to, at the TTI N, the first base station determines that the third UE is not scheduled at the TTI N-T, and delays scheduling of the third UE by one scheduling cycle.
The processing unit 501 is specifically configured to:
when the scheduling period is 8 TTIs, in TTI N +8-T, the first base station determines scheduling information of a third UE of the first cell in TTI N +8, and in TTI N +8, the first base station sends an uplink Grant (UL Grant) to the third UE, wherein new data in the UL Grant indicates that the NDI is not inverted, so that the third UE performs retransmission in a self-adaptive retransmission mode.
In another embodiment, the processing unit 501 is further configured to, in TTI N-S, obtain, by the first base station, retransmission information of a third UE in the first cell, where the retransmission information includes feedback information that the third UE needs to retransmit in the TTI N;
the processing unit 501 is further configured to determine, at the TTI N-T, scheduling information of a third UE in a first cell in the TTI N, where the T is a time delay for the first cell of the first base station to obtain the scheduling information of a second UE in the second cell;
as shown in fig. 8, the base station 50 further includes:
a sending unit 503, configured to send, in the TTI N, an uplink Grant UL Grant to the third UE, where new data in the UL Grant indicates that the NDI is not inverted, so that the third UE performs retransmission in an adaptive retransmission manner.
The processing unit 501 is specifically configured to:
acquiring channel information from the first UE to the first cell, transmission power of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
and calculating the SINR predicted value according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, wherein the channel information comprises channel response estimation.
For example, the SINR prediction value of each subcarrier of each RB allocated to the user equipment may be calculated according to formula (1.1a), and then the SINR prediction values of each subcarrier are combined into the SINR prediction value of the user equipment over the scheduling bandwidth:
then, the SINRs of the subcarriers are combined into an RB-level SINR γnAnd then combined into the predicted SINR value of the user equipment, and the combining formula depends on the adopted receiver. For example, when a Minimum Mean Square Error (MMSE) receiver is used, the SINR of the subcarriers can be first combined into the SINR γ of RB level by using equation (1.2)nAnd then using the formula (1.2) to convert the SINR gamma of RB levelnAnd the SINR predicted values are combined into the SINR predicted value of the user equipment, and the formula (1.2) is as follows:
the processing unit 501 is specifically configured to:
acquiring channel information from the first UE to the first cell, transmission power of the first UE, SINR historical measurement values of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
and correcting the SINR historical measurement value of the first UE according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, and calculating the SINR predicted value, wherein the channel information comprises reference signal receiving power and/or reference signal receiving quality.
As in equation (1.1 b):
γ(t)＝γmeasure(t-s)+λ(t)·[I(t-s)-I(t)]+[P(t)-P(t-s)] (1.1b)
then, SINR of the subcarriers is combined into S of RB levelINRγnAnd then combined into the predicted SINR value of the user equipment, and the combining formula depends on the adopted receiver. For example, using equation (1.2).
An embodiment of the present invention provides a base station 60, as shown in fig. 9, including:
a processing unit 601, configured to determine, at a transmission time interval TTI N-T, scheduling information of a first user equipment UE of a first cell at TTI N, where the scheduling information includes a resource block and a transmission power allocated to the first UE, and where, at the TTI N, the first base station schedules the first UE, and the first cell belongs to the first base station;
the processing unit 601 is further configured to, in TTI N-S, acquire, by the first base station, retransmission information of the first UE in the first cell, where the retransmission information includes feedback information that the first UE needs to retransmit in TTI N;
a sending unit 602, configured to send, in the TTI N, an uplink Grant UL Grant to the first UE, where new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in an adaptive retransmission manner.
In contrast to the prior art, the first base station determines the scheduling information of the first UE of the first cell in TTI N by, at TTI N-T, when in TTI N-S, the first base station acquires retransmission information of the first UE in the first cell, and in the TTI N, the first base station can send an uplink Grant (UL Grant) to the first UE, wherein the new data in the UL Grant indicates that the NDI is not flipped, so that the first UE retransmits in an adaptive retransmission manner, under the non-ideal backhaul scenario, the transmission delay for obtaining the interference factors of other user equipment to the first UE can be overcome, the interference factors of other user equipment to the first UE are considered, the accuracy of the base station for calculating the SINR value of the scheduled first UE of the current cell is improved, therefore, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of the wireless communication system is further improved.
An embodiment of the present invention provides a base station 70, as shown in fig. 10, including:
a memory 701 for storing program code;
a processor 702 for calling the program code stored in the memory to execute the following method: in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
a receiver 703, configured to, in the TTI N, obtain, by the first base station, scheduling information of a second UE of a second cell, where the second cell belongs to a second base station, the scheduling information of the second UE is scheduling information of the second UE in the TTI N, and the scheduling information of the second UE is scheduling information determined by the second base station in the TTI N-T and sent to the first base station;
the processor 702 performs a method further comprising:
when the resource block of the first UE is the same as the resource block of the second UE, the first base station acquires the measurement information of the first UE in the first cell and the measurement information of the second UE in the first cell;
the processor 702 is further configured to, according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE, the first base station obtains a predicted value of a signal to interference plus noise ratio, SINR, of the first UE;
the processor 702 is further configured to obtain, by the first base station, an SINR value of the first UE according to the SINR prediction value and an SINR adjustment amount;
the processor 702 is further configured to determine, by the first base station, an MCS corresponding to the SINR value of the first UE according to a correspondence between the SINR and a modulation and coding scheme, MCS.
Compared with the prior art, the scheduling information of the first UE of the first cell in the TTI N is determined by the first base station in the TTI N-T, and the scheduling information of the second UE determined by the second cell in the TTI N-T and sent to the first base station is obtained by the first base station in the TTI N, so that the transmission delay of the interference factors of other user equipment to the first UE can be overcome under the non-ideal backhaul scene, the interference factors of other user equipment to the first UE are considered, the precision of calculating the SINR value of the scheduled first UE of the current cell by the base station is improved, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of the wireless communication system is improved.
An embodiment of the present invention provides a base station 80, as shown in fig. 11, including:
a memory 801 for storing program codes;
a processor 802 for calling the program code stored in the memory to perform the following method: in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
the processor 802 is further configured to, in TTI N-S, obtain, by the first base station, retransmission information of the first UE in the first cell, where the retransmission information includes feedback information that the first UE needs to retransmit in TTI N;
a transmitter 803, configured to, in the TTI N, send, by the first base station, an uplink Grant UL Grant to the first UE, where new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in an adaptive retransmission manner.
In contrast to the prior art, the first base station determines the scheduling information of the first UE of the first cell in TTI N by, at TTI N-T, when in TTI N-S, the first base station acquires retransmission information of the first UE in the first cell, and in the TTI N, the first base station can send an uplink Grant (UL Grant) to the first UE, wherein the new data in the UL Grant indicates that the NDI is not flipped, so that the first UE retransmits in an adaptive retransmission manner, under the non-ideal backhaul scenario, the transmission delay for obtaining the interference factors of other user equipment to the first UE can be overcome, the interference factors of other user equipment to the first UE are considered, the accuracy of the base station for calculating the SINR value of the scheduled first UE of the current cell is improved, therefore, the MCS is selected according to the SINR value, the accuracy of MCS selection is improved, and the throughput rate of the wireless communication system is further improved.
It should be noted that, the processor is further configured to execute a specific step that the ue needs to perform uplink data transmission, which may refer to the description of the method side. The adaptive modulation and coding method is suitable for scenes with a large number of users.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form. The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be physically included alone, or two or more units may be integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.
Those of ordinary skill in the art will understand that: all or part of the steps for implementing the method embodiments may be implemented by hardware related to program instructions, and the program may be stored in a computer readable storage medium, and when executed, the program performs the steps including the method embodiments; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks. The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (21)

  1. A method for adaptive modulation and coding, comprising:
    in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
    in the TTI N, the first base station acquires scheduling information of second UE of a second cell, the second cell belongs to a second base station, the scheduling information of the second UE is the scheduling information of the second UE in the TTI N, and the scheduling information of the second UE is the scheduling information which is determined by the second base station in the TTI N-T and is sent to the first base station;
    when the resource block of the first UE is the same as the resource block of the second UE, the first base station acquires the measurement information of the first UE in the first cell and the measurement information of the second UE in the first cell;
    according to the measurement information of the first UE, the scheduling information of the first UE, the measurement information of the second UE in a first cell and the scheduling information of the second UE, the first base station obtains a signal to interference plus noise ratio (SINR) predicted value of the first UE;
    the first base station obtains an SINR value of the first UE according to the SINR predicted value and the SINR adjustment amount;
    and the first base station determines the MCS corresponding to the SINR value of the first UE according to the corresponding relation between the SINR and the modulation and coding scheme MCS.
  2. The method of adaptive modulation and coding according to claim 1, wherein after the first base station determines the scheduling information of the first user equipment UE of the first cell in TTI N at the transmission time interval TTI N-T, the method further comprises:
    in TTI N-S, the first base station acquires retransmission information of a third UE in the first cell, wherein the retransmission information comprises feedback information that the third UE needs to retransmit in TTI N, S is smaller than T, and T is the time delay of the first cell of the first base station acquiring scheduling information of a second UE of the second cell;
    and in the TTI N, the first base station determines that the third UE is not scheduled in the TTI N-T, and delays the third UE for scheduling by one scheduling period.
  3. The method of adaptive modulation and coding according to claim 2, wherein the delaying the third UE by one scheduling period comprises:
    when the scheduling period is 8 TTIs, in TTI N +8-T, the first base station determines scheduling information of a third UE of the first cell in TTI N +8, and in TTI N +8, the first base station sends an uplink Grant (UL Grant) to the third UE, wherein new data in the UL Grant indicates that NDI (network data interface) does not turn over, so that the third UE performs retransmission in a self-adaptive retransmission mode.
  4. The method of adaptive modulation and coding according to claim 1, further comprising:
    in TTI N-S, the first base station acquires retransmission information of a third UE in the first cell, wherein the retransmission information comprises feedback information which needs to be retransmitted by the third UE in TTI N;
    in the TTI N-T, the first base station determines the scheduling information of the third UE of the first cell in the TTI N, and the T is the time delay of the first cell of the first base station for acquiring the scheduling information of the second UE of the second cell;
    after the first base station acquires scheduling information of a second UE of a second cell, the method further includes:
    and in the TTI N, the first base station sends an uplink Grant (UL Grant) to the third UE, wherein new data in the UL Grant indicates that the NDI is not inverted, so that the third UE performs retransmission in a self-adaptive retransmission mode.
  5. The method according to claim 3 or 4, wherein the obtaining, by the first base station, the predicted SINR value of the first UE according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE comprises:
    acquiring channel information from the first UE to the first cell, transmission power of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
    and calculating the SINR predicted value according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, wherein the channel information comprises channel response estimation.
  6. The method according to claim 3 or 4, wherein the obtaining, by the first base station, the predicted SINR value of the first UE according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE comprises:
    acquiring channel information from the first UE to the first cell, transmission power of the first UE, SINR historical measurement values of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
    and correcting the SINR historical measurement value of the first UE according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, and calculating the SINR predicted value, wherein the channel information comprises reference signal receiving power and/or reference signal receiving quality.
  7. A method for adaptive modulation and coding, comprising:
    in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
    in TTI N-S, the first base station acquires retransmission information of the first UE in the first cell, wherein the retransmission information comprises feedback information that the first UE needs to retransmit in TTI N;
    and in the TTI N, the first base station sends an uplink Grant (UL Grant) to the first UE, wherein new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in a self-adaptive retransmission mode.
  8. A base station, comprising:
    a processing unit, configured to determine, at a transmission time interval TTI N-T, scheduling information of a first user equipment UE of a first cell at TTI N, where the scheduling information includes a resource block and a transmission power allocated to the first UE, and where, at the TTI N, the first base station schedules the first UE, and the first cell belongs to the first base station;
    an obtaining unit, configured to obtain, at the TTI N, scheduling information of a second UE of a second cell by the first base station, where the second cell belongs to a second base station, the scheduling information of the second UE is scheduling information of the second UE at the TTI N, and the scheduling information of the second UE is scheduling information determined by the second base station at the TTI N-T and sent to the first base station;
    the obtaining unit is further configured to, when the resource block of the first UE is the same as the resource block of the second UE, obtain, by the first base station, measurement information of the first UE in the first cell and measurement information of the second UE in the first cell;
    the processing unit is further configured to, according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE, the first base station obtains a predicted value of a signal to interference plus noise ratio SINR of the first UE;
    the processing unit is further configured to obtain, by the first base station, an SINR value of the first UE according to the SINR predicted value and an SINR adjustment amount;
    the processing unit is further configured to determine, by the first base station, an MCS corresponding to the SINR value of the first UE according to a correspondence between the SINR and a modulation and coding scheme, MCS.
  9. The base station of claim 8,
    the processing unit is further configured to, in TTI N-S, acquire, by the first base station, retransmission information of a third UE in the first cell, where the retransmission information includes feedback information that the third UE needs to retransmit in TTI N, and S is smaller than T, where T is a time delay for acquiring, by the first cell of the first base station, scheduling information of a second UE of the second cell;
    the processing unit is further configured to, at the TTI N, the first base station determines that the third UE is not scheduled at the TTI N-T, and delay the third UE for scheduling by one scheduling period.
  10. The base station of claim 9, wherein the processing unit is specifically configured to:
    when the scheduling period is 8 TTIs, in TTI N +8-T, the first base station determines scheduling information of a third UE of the first cell in TTI N +8, and in TTI N +8, the first base station sends an uplink Grant (UL Grant) to the third UE, wherein new data in the UL Grant indicates that NDI (network data interface) does not turn over, so that the third UE performs retransmission in a self-adaptive retransmission mode.
  11. The base station of claim 8,
    the processing unit is further configured to, in TTI N-S, acquire, by the first base station, retransmission information of a third UE in the first cell, where the retransmission information includes feedback information that the third UE needs to retransmit in TTI N;
    the processing unit is further configured to determine, at the TTI N-T, scheduling information of a third UE of a first cell in the TTI N, where the T is a time delay for the first cell of the first base station to acquire the scheduling information of the second UE of the second cell;
    the base station further comprises:
    a sending unit, configured to send, by the first base station, an uplink Grant UL Grant to the third UE in the TTI N, where new data in the UL Grant indicates that the NDI is not inverted, so that the third UE performs retransmission in an adaptive retransmission manner.
  12. The base station according to claim 10 or 11, wherein the processing unit is specifically configured to:
    acquiring channel information from the first UE to the first cell, transmission power of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
    and calculating the SINR predicted value according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, wherein the channel information comprises channel response estimation.
  13. The base station according to claim 10 or 11, wherein the processing unit is specifically configured to:
    acquiring channel information from the first UE to the first cell, transmission power of the first UE, SINR historical measurement values of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
    and correcting the SINR historical measurement value of the first UE according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, and calculating the SINR predicted value, wherein the channel information comprises reference signal receiving power and/or reference signal receiving quality.
  14. A base station, comprising:
    a processing unit, configured to determine, at a transmission time interval TTI N-T, scheduling information of a first user equipment UE of a first cell at TTI N, where the scheduling information includes a resource block and a transmission power allocated to the first UE, and where, at the TTI N, the first base station schedules the first UE, and the first cell belongs to the first base station;
    the processing unit is further configured to, in TTI N-S, acquire, by the first base station, retransmission information of the first UE in the first cell, where the retransmission information includes feedback information that the first UE needs to retransmit in TTI N;
    a sending unit, configured to send, by the first base station, an uplink Grant UL Grant to the first UE in the TTI N, where new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in an adaptive retransmission manner.
  15. A base station, comprising:
    a memory for storing program code;
    a processor for calling the program code stored in the memory to execute the following method: in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
    a receiver, configured to, in the TTI N, obtain, by the first base station, scheduling information of a second UE of a second cell, where the second cell belongs to a second base station, the scheduling information of the second UE is scheduling information of the second UE in the TTI N, and the scheduling information of the second UE is scheduling information that is determined by the second base station in the TTI N-T and is sent to the first base station;
    the processor-implemented method further comprises:
    when the resource block of the first UE is the same as the resource block of the second UE, the first base station acquires the measurement information of the first UE in the first cell and the measurement information of the second UE in the first cell;
    the processor is further configured to, according to the measurement information of the first UE and the scheduling information of the first UE, and the measurement information of the second UE in the first cell and the scheduling information of the second UE, the first base station obtains a predicted value of a signal to interference plus noise ratio SINR of the first UE;
    the processor is further configured to obtain, by the first base station, an SINR value of the first UE according to the SINR predicted value and an SINR adjustment amount;
    the processor is further configured to determine, by the first base station, an MCS corresponding to the SINR value of the first UE according to a correspondence between the SINR and a modulation and coding scheme, MCS.
  16. The base station of claim 15,
    the processor is further configured to, at TTI N-S, obtain, by the first base station, retransmission information of a third UE in the first cell, where the retransmission information includes feedback information that the third UE needs to retransmit at TTI N, where S is smaller than T, and T is a time delay for the first cell of the first base station to obtain scheduling information of the second UE of the second cell;
    the processor is further configured to, at the TTI N, the first base station determine that the third UE is not scheduled at the TTI N-T, and delay the third UE for one scheduling cycle scheduling.
  17. The base station of claim 16, wherein the processor is specifically configured to:
    when the scheduling period is 8 TTIs, in TTI N +8-T, the first base station determines scheduling information of a third UE of the first cell in TTI N +8, and in TTI N +8, the first base station sends an uplink Grant (UL Grant) to the third UE, wherein new data in the UL Grant indicates that NDI (network data interface) does not turn over, so that the third UE performs retransmission in a self-adaptive retransmission mode.
  18. The base station of claim 15,
    the processor is further configured to, at TTI N-S, obtain, by the first base station, retransmission information of a third UE in the first cell, where the retransmission information includes feedback information that the third UE needs to retransmit at TTI N;
    the processor is further configured to determine, at the TTI N-T, scheduling information of a third UE of a first cell at the TTI N, where the T is a time delay for the first cell of the first base station to obtain the scheduling information of the second UE of the second cell;
    the base station further comprises:
    a transmitter, configured to send, by the first base station, an uplink Grant UL Grant to the third UE in the TTI N, where new data in the UL Grant indicates that the NDI is not inverted, so that the third UE performs retransmission in an adaptive retransmission manner.
  19. The base station according to claim 17 or 18, wherein the processor is specifically configured to:
    acquiring channel information from the first UE to the first cell, transmission power of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
    and calculating the SINR predicted value according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, wherein the channel information comprises channel response estimation.
  20. The base station according to claim 17 or 18, wherein the processor is specifically configured to:
    acquiring channel information from the first UE to the first cell, transmission power of the first UE, SINR historical measurement values of the first UE, channel information from the second UE to the first cell, transmission power of the second UE and interference noise estimation of the first UE except the first cell and the second cell on the resource block;
    and correcting the SINR historical measurement value of the first UE according to the channel information from the first UE to the first cell, the transmission power of the first UE, the channel information from the second UE to the first cell, the transmission power of the second UE and the interference noise estimation of the first UE except the first cell and the second cell, and calculating the SINR predicted value, wherein the channel information comprises reference signal receiving power and/or reference signal receiving quality.
  21. A base station, comprising:
    a memory for storing program code;
    a processor for calling the program code stored in the memory to execute the following method: in a transmission time interval TTI N-T, a first base station determines scheduling information of a first user equipment UE of a first cell in TTI N, wherein the scheduling information comprises resource blocks and transmission power allocated to the first UE, and the first base station schedules the first UE in TTI N, and the first cell belongs to the first base station;
    the processor is further configured to, at TTI N-S, obtain, by the first base station, retransmission information of the first UE in the first cell, where the retransmission information includes feedback information that the first UE needs to retransmit at TTI N;
    a transmitter, configured to send, by the first base station, an uplink Grant UL Grant to the first UE in the TTI N, where new data in the UL Grant indicates that the NDI is not inverted, so that the first UE performs retransmission in an adaptive retransmission manner.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112104581A (en) * 2019-06-17 2020-12-18 中国电信股份有限公司 Modulation-demodulation method, modulation-demodulation device and computer-readable storage medium

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109417814B (en) 2016-07-25 2020-09-29 华为技术有限公司 Scheduling method, power control method and base station
CN113873570B (en) * 2020-06-30 2023-11-03 华为技术有限公司 Interference coordination method and related equipment

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120315935A1 (en) * 2011-06-07 2012-12-13 Ke Wang Helmersson System and method for determining the severity of interference in different areas of a cellular radio network and coordinating radio resource management features in response
CN103202058A (en) * 2010-10-29 2013-07-10 夏普株式会社 Mobile station device, wireless communication method, and integrated circuit
US20130188576A1 (en) * 2012-01-19 2013-07-25 Futurewei Technologies, Inc. Systems and Methods for Uplink Resource Allocation
CN103503352A (en) * 2010-12-02 2014-01-08 交互数字专利控股公司 Systems and methods for improving channel quality indication feedback accuracy in wireless communication using interference prediction

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103202058A (en) * 2010-10-29 2013-07-10 夏普株式会社 Mobile station device, wireless communication method, and integrated circuit
CN103503352A (en) * 2010-12-02 2014-01-08 交互数字专利控股公司 Systems and methods for improving channel quality indication feedback accuracy in wireless communication using interference prediction
US20120315935A1 (en) * 2011-06-07 2012-12-13 Ke Wang Helmersson System and method for determining the severity of interference in different areas of a cellular radio network and coordinating radio resource management features in response
US20130188576A1 (en) * 2012-01-19 2013-07-25 Futurewei Technologies, Inc. Systems and Methods for Uplink Resource Allocation

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112104581A (en) * 2019-06-17 2020-12-18 中国电信股份有限公司 Modulation-demodulation method, modulation-demodulation device and computer-readable storage medium

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