CN101111048B - Method for dynamic regulation of wireless resource block configuration based on offset - Google Patents

Abstract

The present invention provides a dynamic adjustment method of a radio resource block configuration based on a offset, which comprises the following procedures: S102, an offset aggregation is determined according to the radio resource configuration attribute in the radio resource block; S104, one offset is periodically and non-periodically selected from the offset aggregation and the part and the whole radio resource configuration in the radio resource block are changed according to the chosen offset; S106, the transmission data is dispatched according to the changed radio resource block. The change of the sub-carrier configuration in the RB through the technical proposal enables the channel capacity of the sub-channel based on the RB band width in the OFDM system to one or a plurality of receivers to be optimized statistically, thereby improving the transmitted throughput, and in particular to be suitable for a forth mobile communication system.

Description

Offset-based dynamic adjustment method for wireless resource block configuration

technical field

The invention relates to access technology in a communication system, in particular to a method for dynamically adjusting wireless resource block configuration based on offset.

Background technique

With the evolution of cellular systems, OFDMA (Orthogonal Frequency Division Multiple Access, Orthogonal Frequency Division Multiple Access) systems have gradually become the mainstream technology for future broadband mobile communications. The core idea of OFDM (Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing) system is to use IFFT (Inverse Fast Fourier Transform) to modulate the data stream on multiple subcarriers, divide the frequency response of the channel, and make it into Parallel, independent, approximately memoryless multiple sub-channels. Therefore, the basic wireless resources of the OFDM system are frequency and time (or time interval). If combined with coding technology and multi-antenna technology, the OFDM system can also obtain additional codeword resources or space resources, using OFDM orthogonal time-frequency resources to obtain Multiple access transmission capability, the system is OFDMA system.

Reducing overhead is an important means for wireless communication systems to obtain higher spectral efficiency. Under the same subcarrier frequency interval, the larger the system bandwidth and the more subcarriers, the greater the overhead of assigning subcarriers for multiple access transmission. At the same time, on the one hand, , transmitting as much data as possible at one time can reduce system overhead. On the other hand, the data length of most services is not fixed, so resource blocks are designed so that they can carry services of smaller lengths, and multiple resource blocks can be combined at the same time. It is very necessary to transmit the business of relatively large length. For example, in the LTE (Long Term Evolution, Long Term Evolution) system, it is defined that an RB includes 12 subcarriers and a time interval of 1 ms, and the subcarrier configuration in the RB is fixed.

In order to improve spectrum utilization, wireless communication systems will adopt adaptive modulation and coding scheme (MCS) according to channel conditions. MCS is usually hierarchical and limited. Base stations and terminals will use multiple RBs (Resource Blocks, resource blocks) to transmit a Data block (TB, transport block), in order to reduce notification overhead, different RBs within a TB use the same MCS. When the subcarrier configuration in the system RB is fixed, since the channel has frequency selection and time selectivity in most cases, and the resources occupied by the TB are only part of the channel resources, the MCS allocated for the TB may not be optimal, so This results in a decrease in spectrum utilization.

Contents of the invention

Considering the problem that the fixed RB subcarrier configuration in the prior art cannot keep the OFDMA channel capacity always large, the present invention is proposed. For this reason, the present invention aims to provide a method based on orthogonal frequency division A method for dynamically adjusting wireless resource block allocation of OFDM subcarrier offset, so that the overall throughput or spectrum utilization rate of a wireless communication system adopting Orthogonal Frequency Division Multiplexing (OFDM) technology is greater.

According to the present invention, a method for dynamically adjusting wireless resource block configuration based on offset is provided.

The method includes the following processing: step S102, determine an offset set according to the radio resource configuration attribute in the radio resource block; step S104, periodically or aperiodically select an offset from the offset set, and according to the selected offset Change the wireless resource configuration in part or all of the wireless resource blocks; step S106, schedule the data to be transmitted according to the changed wireless resource blocks.

In step S102, the radio resource configuration attribute is the radio resource configuration mode in the radio resource block, including: mode 1, all radio resource block configurations of the OFDM system are the same; mode 2, radio resource block configurations of the OFDM system are different.

In step S102, the process of determining the offset set is specifically: when the radio resource configuration mode in the radio resource block is mode 1, select some or all of the offsets in 0-A-1 as the offset set elements of , where A is the number of subcarriers in the radio resource block; when the radio resource configuration mode in the radio resource block is mode 2, select some or all of the offsets in 0 to B-1 as the offset elements in the set, where B is the total number of subcarriers in the OFDM system.

In step S104, the process of periodically or aperiodically selecting an offset from the offset set is specifically: the sender selects an offset from the offset set periodically or aperiodically or aperiodically according to the feedback information of the receiver. displacement.

Wherein, the above-mentioned process of the sender selecting an offset according to the feedback information of the receiver is specifically: the receiver calculates the channel quality test value of the radio resource block under part or all of the offset; the receiver calculates part or all of the offset In the case of an offset, based on the channel quality index information of the radio resource block; the receiver feeds back part or all of the offset information to the sender; the sender selects an offset according to a predetermined offset selection principle.

The above offset information is any of the following: offset; offset and corresponding channel quality index information; offset set and corresponding channel quality index information set; offset and corresponding channel quality test value; A set of offsets and a corresponding set of channel quality test values.

The above process of the sender choosing an offset by itself is as follows: the sender counts the data transmission quality under the current offset; the sender adjusts the offset according to the change of the data transmission quality; the sender tries to adjust the offset, and Send data on the radio resource block corresponding to the adjusted offset until the offset trial adjustment ends; after the trial adjustment ends, the sender selects an offset with the best transmission quality from the trial results.

In step S104, the process of changing the radio resource configuration in some or all of the radio resource blocks is specifically: the sender changes the subcarriers contained in some or all of the radio resource blocks according to the selected offset and according to a predetermined offset mapping method Element. The predetermined offset mapping method is: under a specific offset, the mapping relationship between the logical numbers of logically continuous subcarriers and the physical numbers of physically discrete subcarriers; where the number of radio resource blocks and the corresponding The logical number of the subcarrier. In addition, when there is a static radio resource block, the mapping relationship between the logical number and the physical number of the subcarriers in the static radio resource block is the same under different offsets.

In step S106, the process of scheduling the data to be transmitted according to the changed radio resource block is specifically: the sender schedules to send the data to be transmitted to one or more receivers on the changed radio resource block according to the scheduling strategy.

In addition, in step S102, the radio resource block includes: time-frequency resources, a combination of time-frequency resources, codeword resources or space resources, or both.

Through the above-mentioned technical solution of the present invention, by changing the subcarrier configuration in the RB, the channel capacity of the subchannel based on the TB bandwidth of the RB in the OFDM system bandwidth is statistically optimized for one or more receivers, thereby improving It improves the throughput of transmission and is especially suitable for the fourth generation mobile communication system.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, and are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention. In the attached picture:

FIG. 1 is a flow chart of a method for dynamically adjusting wireless resource block configuration based on an offset according to an embodiment of the present invention;

Figure 2 is a flowchart of Example 1 of the method shown in Figure 1; and

FIG. 3 is a flowchart of Example 2 of the method shown in FIG. 1 .

Detailed ways

The preferred embodiments of the present invention will be described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

The present invention involves radio resource blocks (RBs), and the RBs will first be described in detail below.

(1) RB can be divided into two types according to configuration

The radio resource configuration modes in the radio resource blocks include the following two modes: mode 1, all radio resource blocks in the OFDM system are configured the same; mode 2, radio resource blocks in the OFDM system are configured differently. Correspondingly, RBs can be divided into two types according to the configuration: the radio resource blocks of all OFDM systems in the first type of radio resource blocks have the same configuration, that is, the above-mentioned method 1 is adopted, that is to say, the radio resource blocks of the OFDM system are at least time-frequency There is only one size configuration of resources, the number of subcarriers in different RBs is the same, and the number of OFDM symbols contained in them is also the same; the radio resource block configurations of the OFDM system in the second type of radio resource block are different, that is, the above method two .

(2) RB can be divided into two types according to subcarrier distribution

Centralized RB: If the subcarrier frequencies in the RB are continuous, the RB is called a centralized RB;

Distributed RB: RB other than centralized RB.

(3) RB is divided into two categories according to the mode

Dynamic RB: The subcarrier components contained in the dynamic RB are variable;

Static RB: The subcarrier components included in the static RB are invariable.

(4) RB is classified according to attributes

Logical (or virtual) RB: The subcarriers contained in this RB are virtual, and the logical subcarrier numbers are continuous, and the logical subcarriers in a specific numbered RB are always unchanged;

Physical RB: This RB contains physical subcarriers. The number of physical subcarriers in a specific numbered RB is not necessarily continuous. The physical subcarriers in a specific numbered RB can always remain the same or can be changed.

There is a specific mapping relationship between logical subcarrier numbers and physical subcarriers in a logical (or virtual) RB, and the mapping relationship may be the same or different under different offsets.

In addition, the sender mentioned below may be a base station (Base Station, BS) or an access point (Access Point, AP), and the receiver may be a terminal (User Equipment, UE).

Based on the above content, as shown in FIG. 1, the offset-based RB configuration dynamic adjustment method according to the embodiment of the present invention includes the following processing:

Step S102, determine the offset set according to the radio resource configuration attribute in the RB; Step S104, periodically or aperiodically select an offset from the offset set, and change part or all of the RBs according to the selected offset radio resource configuration; Step S106, schedule data to be transmitted according to the changed RB.

Various details in the above processing will be specifically described below.

First of all, the above-mentioned RB of the OFDM system refers to time-frequency (i.e. time or time interval and frequency or subcarrier) resources, or a combination of time-frequency resources, codeword resources, and space resources. OFDM frequency resources refer to A set of subcarriers in an OFDM system.

In step S102, the radio resource configuration attribute is the radio resource configuration mode in the RB, including: mode 1, all RB configurations in the OFDM system are the same; mode 2, RB configurations in the OFDM system are different.

Correspondingly, in step S102, the process of determining the offset set is specifically: when the radio resource configuration mode in the RB is mode 1, select part or all of the offsets in 0-A-1 as the offset set elements in , where A is the number of subcarriers in the RB; when the radio resource configuration method in the RB is method 2, select some or all of the offsets from 0 to B-1 as the offset set Elements, where B is the total number of subcarriers in the OFDM system.

In step S104, the process of periodically or aperiodically selecting an offset from the offset set is specifically: the sender selects an offset from the offset set periodically or aperiodically or aperiodically according to the feedback information of the receiver. displacement. The method for selecting the offset can be determined according to different principles (eg, minimum block error rate, maximum throughput, etc.), which is not limited in the present invention.

Among them, the above-mentioned process of the sender selecting an offset according to the feedback information of the receiver is specifically: the receiver calculates the channel quality test value of the RB under part or all of the offset; the receiver calculates part or all of the offset. , based on RB channel quality index information; the receiver feeds back part or all of the offset information to the sender; the sender selects an offset according to a predetermined offset selection principle (the following will be described in detail in conjunction with Example 1).

The above process of the sender choosing an offset by itself is as follows: the sender counts the data transmission quality under the current offset; the sender adjusts the offset according to the change of the data transmission quality; the sender tries to adjust the offset, and Send data on the RB corresponding to the adjusted offset until the offset trial adjustment ends; after the trial adjustment ends, the sender selects an offset with the best sending quality from the trial results (the following will be combined with Example 2 be described in detail).

In step S104, the process of changing the radio resource configuration in some or all of the RBs is specifically: the sender changes the subcarrier components included in some or all of the RBs according to a predetermined offset mapping method according to the selected offset.

As mentioned above, the RBs of the OFDM system can be divided into two types, one is called dynamic RB, and the subcarrier components contained in the dynamic RB are variable, and the other is called static RB, and the subcarrier components contained in the static RB are not variable . The RBs in the OFDM system may only have static RBs, may only have dynamic RBs, and may also have both dynamic RBs and static RBs. In addition, the subcarriers of the OFDM system are numbered from small to large in frequency, which is called the physical number, and the subcarrier number in the RB is the subcarrier logical number. For the centralized RB, the logical number and the physical number are the same when the offset is 0. , for a distributed RB, when the offset is 0, there is a definite mapping relationship between the logical number and the physical number.

Based on this, the above-mentioned predetermined offset mapping method is: under a specific offset, the logical numbers of the logically continuous subcarriers (the logical numbers of the subcarriers in the RB are continuous) and the numbers of the physically discrete subcarriers The mapping relationship of the physical number (the physical number corresponds to the actual frequency of the subcarrier).

Wherein, the number of the RB and the logical number of the corresponding subcarrier need to be defined in advance. One way of definition is that the logical number of the subcarriers in the RB with a large number is always greater than the logical number of the subcarriers in an RB with a small number, for example: RB0 includes LSC0-11, VRB1 includes LSC12-23, . . . In addition, when there is a static RB, the mapping relationship between the logical number and the physical number of the subcarriers in the static RB is the same under different offsets.

In step S106, the process of scheduling the data to be transmitted according to the changed RB is specifically: the sender schedules the data to be transmitted to one or more receivers on the changed RB according to the scheduling policy.

Embodiments of the present invention will be further described below through examples.

Example 1: The sender selects an offset based on the feedback information from the receiver, where the sender is BS and the receiver is UE

As shown in Figure 2, the present invention under this example comprises following processing:

Step S202, determining an offset set according to the radio resource configuration attribute in the radio resource block;

Assuming that the frequency resource bandwidth of the OFDM system carrying data is 9MHz, and the subcarrier spacing is 15KHz, the number of useful subcarriers is 600 except for DC (that is, the 0Hz subcarrier), which is set from -4.5MHz to 4.5MHz, and the subcarriers (sub- carrier) is numbered SC0~SC599, 50 resource blocks (RB0~RB49), each RB contains 12 subcarriers, and the offset set is {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11}, RB is a centralized allocation mode, that is, the subcarriers in each RB are continuous, such as corresponding to an offset of 0, RB0 contains subcarriers SC0, SC1, ..., SC11, RB1 contains SC12, SC13, ..., SC23, and so on, different RBs contain different numbers of subcarriers. RB can also be in a distributed allocation mode, that is, to establish a mapping relationship between logically continuous subcarrier numbers (such as LSC0~LSC599) and physically discrete subcarrier numbers, for example, the m+12×n logical subcarrier and the m×50+n physical subcarriers correspond, where m=0-11, n=0-49. In the distributed allocation mode, corresponding to an offset of 0, RB0 includes subcarriers LSC0, LSC1, ..., LSC11, RB1 includes LSC12, LSC13, ..., LSC23, and so on. OFDM system modulation and coding scheme (MCS) is divided into 6 types, 1# is (QPSK, 1/3Turbo code), 2# is (QPSK, 1/2Turbo code), 3# is (16QAM, 1/3Turbo code), 4# is (16QAM, 1/2Turbo code), 5# is (64QAM, 1/3Turbo code), and 6# is (64QAM, 1/2Turbo code).

Step S204, the UE counts the channel quality measurement value of the RB under all or part of the offset, such as: signal-to-noise ratio (SNR), signal-to-interference-plus-noise ratio (SINR), signal strength, channel time selectivity parameters, frequency selection Sexual parameters, or any combination of the above parameters.

In step S206, the UE calculates RB-based channel quality index information under all or part of the offset. The RB-based channel quality index information refers to the quantized value or statistical value of the channel quality measurement value, and the RB position information corresponding to the quantized value or statistical value, such as corresponding to offset 7 and RB8 The equivalent signal-to-interference-plus-noise ratio (SINR) is 10dB or the level is 3 or the modulation coding method (MCS) is 3#

Step S208, the UE feeds back part or all of the offset information to the BS, for example: the UE feeds back the channel quality information of the RB under all 12 offsets to the BS, or the UE feeds back the channel quality information of the RB under a partial offset to the BS Information, such as only feeding back one or better offsets or offsets and all or part of the RB channel quality information under the corresponding offsets, or offsets and corresponding offsets that the UE considers the best RB channel quality Further statistical information of all or part of the RB channel quality information under the quantity. Specifically, in this application example, the UE feeds back 50 RB positions and corresponding CQIs under all offsets from 1 to 12, or feeds back one of the offsets from 1 to 12, such as offset 7 .

In step S210, the offset is determined according to the offset selection principle. The BS receives the set of offset information fed back by Y UEs, where Y is less than or equal to X, and according to the principle of offset selection (for example, to maximize the throughput of sending data to Y UEs, or to send Y subs to Y UEs The sum of the channel capacities is the largest), and the offset is determined.

In step S212, the BS sends data under the new RB configuration. The BS notifies the receiver to refresh the offset, and sends data to all or some of the X UEs on the RB corresponding to the refreshed offset;

In step S214, the UE receives the data sent to itself on the RB corresponding to the refreshed offset according to the resource assignment information. (step S204-step S214 is the flow process that the sender sends data to X receivers at the same time)

Example 2: The sender chooses an offset by itself, where the sender is BS and the receiver is UE

As shown in Figure 3, the present invention under this example comprises following processing:

Step S302, determining an offset set according to the radio resource configuration attribute in the radio resource block;

Assuming that the frequency resource bandwidth of the OFDM system carrying data is 9MHz, and the subcarrier spacing is 15KHz, the number of useful subcarriers is 600 except for DC (that is, the 0Hz subcarrier), which is set from -4.5MHz to 4.5MHz, and the subcarriers (sub- carrier) is numbered SC0~SC599, 50 resource blocks (RB0~RB49), each RB contains 12 subcarriers, and the offset set is {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11}, RB is a centralized allocation mode, that is, the subcarriers in each RB are continuous, such as corresponding to an offset of 0, RB0 contains subcarriers SC0, SC1, ..., SC11, RB1 contains SC12, SC13, ..., SC23, and so on, different RBs contain different numbers of subcarriers. RB can also be in a distributed allocation mode, that is, to establish a mapping relationship between logically continuous subcarrier numbers (such as LSC0~LSC599) and physically discrete subcarrier numbers, for example, the m+12×n logical subcarrier and the m×50+n physical subcarriers correspond, where m=0-11, n=0-49. In the distributed allocation mode, corresponding to an offset of 0, RB0 includes subcarriers LSC0, LSC1, ..., LSC11, RB1 includes LSC12, LSC13, ..., LSC23, and so on. OFDM system modulation and coding scheme (MCS) is divided into 6 types, 1# is (QPSK, 1/3Turbo code), 2# is (QPSK, 1/2Turbo code), 3# is (16QAM, 1/3Turbo code), 4# is (16QAM, 1/2Turbo code), 5# is (64QAM, 1/3Turbo code), 6# is (64QAM, 1/2Turbo code);

Step S304, the BS sends data to some or all of the X UEs on the corresponding RB with the current offset;

In step S306, the BS counts the data transmission quality under the current offset. Data transmission quality can be measured by reliability indices such as frame error rate and bit error rate. The reliability index can be obtained by counting the acknowledgment information (such as: ACK/NACK) or measurement information fed back by one or more receivers, or it can be counted according to the number of BS retransmissions;

Step S308, the BS adjusts the offset according to the change of the data transmission quality, for example, setting a transmission quality threshold, when the transmission quality is lower than the threshold, start to adjust the offset until the transmission quality improves or finds in the offset set An optimal integer offset results in the best sending quality. In order to avoid repeated adjustments when the transmission quality is lower than the threshold at all offsets, you can also set the adjustment cycle, find the offset with the best transmission quality within the adjustment cycle, and stop the adjustment until the next adjustment cycle begins, and then repeat adjustment process;

In step S310, the BS tries to adjust the offset, and sends data on the RB corresponding to the adjusted offset until the offset adjustment ends;

Step S312, if the trial adjustment is over, go to step S314, if the trial adjustment is not over, go to step S310;

In step S314, select the offset with the best transmission quality and the newest offset from the trial results, and send data on the RB corresponding to the refreshed offset, and return to step S306.

In this way, by means of the present invention, by changing the subcarrier configuration in the RB, the channel capacity of the subchannel based on the RB bandwidth in the OFDM system bandwidth is statistically optimized for one or more receivers, thereby improving the transmission efficiency. throughput.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A method for dynamically adjusting wireless resource block configuration based on an offset, characterized in that, comprising: Step S102, determining an offset set according to the radio resource configuration attribute in the radio resource block; Step S104, periodically or aperiodically selecting an offset from the set of offsets, and changing the radio resource configuration in some or all of the radio resource blocks according to the selected offset; and Step S106, scheduling data to be transmitted according to the changed radio resource block; In the step S102, the radio resource configuration attribute is the radio resource configuration mode in the radio resource block, including: mode 1, all radio resource block configurations of the OFDM system are the same; mode 2, radio resource block configurations of the OFDM system are different ; In the step S102, the process of determining the offset set is specifically: When the radio resource configuration mode in the radio resource block is the first mode, select some or all of the offsets in 0 to A-1 as the elements in the offset set, where A is the The number of subcarriers; and When the radio resource configuration mode in the radio resource block is the mode 2, select some or all of the offsets from 0 to B-1 as the elements in the offset set, where B is the offset in the OFDM system The total number of subcarriers. 2. The method according to claim 1, characterized in that, in the step S104, the process of periodically or aperiodically selecting an offset from the offset set is specifically: The sender selects an offset from the offset set by itself or periodically or aperiodically according to the feedback information of the receiver. 3. The method according to claim 2, wherein the process of selecting an offset by the sender according to the feedback information of the receiver is specifically: The receiving party counts the channel quality test value of the wireless resource block under some or all offsets; The receiver calculates part or all of the offset, based on the channel quality index information of the radio resource block; The receiver feeds back part or all of the offset information to the sender; and The sender selects an offset according to a predetermined offset selection principle. 4. The method according to claim 3, wherein the offset information is any of the following: Offset; Offset and corresponding channel quality index information; A set of offsets and a corresponding set of channel quality index information; Offset and corresponding channel quality test value; A set of offsets and a corresponding set of channel quality test values. 5. The method according to claim 2, wherein the process of selecting an offset by the sender is specifically: The sender counts the data transmission quality under the current offset; The sender adjusts the offset according to changes in data transmission quality; The sender tries to adjust the offset, and sends data on the radio resource block corresponding to the adjusted offset until the offset adjustment ends; and After the trial adjustment ends, the sender selects an offset with the best sending quality from the trial results. 6. The method according to claim 1, characterized in that, in the step S104, the process of changing the radio resource configuration in part or all of the radio resource blocks is specifically: The sender changes the subcarrier components included in some or all of the radio resource blocks according to the selected offset and according to a predetermined offset mapping manner. 7. The method according to claim 6, wherein the predetermined offset mapping method is: under a specific offset, the logical numbers of logically continuous subcarriers and the physical numbers of physically discrete subcarriers The mapping relationship of the numbers; wherein, the numbers of the radio resource blocks and the logical numbers of the corresponding subcarriers are defined in advance. 8. The method according to claim 7, wherein when there is a static radio resource block, the mapping relationship between the logical number and the physical number of the subcarriers in the static radio resource block is the same under different offsets. 9. The method according to claim 1, characterized in that, in the step S106, the process of scheduling the data to be transmitted according to the changed radio resource block is specifically: The sender schedules to send the data to be transmitted to one or more receivers according to the scheduling strategy on the changed wireless resource block. 10. The method according to any one of claims 1 to 9, characterized in that, in the step S102, the wireless resource block includes: time-frequency resources, time-frequency resources and codeword resources or space resources either or a combination of both.

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