KR100933130B1 - Band AMC Subchannel Allocation Method in Portable Internet System - Google Patents

Abstract

The present invention relates to a method for allocating a band AMC subchannel in a portable Internet system and a computer-readable recording medium recording a program for realizing the method. In the environment, when the UEs prefer a specific AMC band, the band AMC subchannel in the portable Internet system for efficiently transitioning from the general subchannel mode to the band AMC subchannel mode without the overhead of band reallocation. A computer-readable recording medium having recorded thereon an allocation method and a program for realizing the method.

To this end, the present invention provides a method for allocating a band AMC subchannel in a terminal, the method comprising: requesting a base station to transition to a band AMC mode; A band information transmitting step of transmitting a predetermined number of band information to the base station in order of worst state according to a channel state report request from the base station; A signal-to-interference noise ratio transmission step of transmitting a signal-to-interference noise ratio for the band allocated from the base station to the base station; And transmitting a difference value of a signal-to-interference noise ratio for a band allocated from the base station.

Description

Method for allocating band Adaptive Modulation and Coding subchannel in mobile internet system

The present invention relates to a method for allocating a band AMC subchannel in a portable Internet system and a computer readable recording medium recording a program for realizing the method. In a low mobility environment of the mobile Internet system, in order to efficiently transition from the general subchannel mode to the band AMC subchannel mode without the overhead of band reallocation when the UEs prefer a specific AMC band, A band AMC subchannel allocation method and a computer readable recording medium having recorded thereon a program for realizing the method.

The present invention is derived from the research conducted as part of the IT new growth engine core technology development project of the Ministry of Information and Communication and the Ministry of Information and Telecommunication Research and Development. [Task Management Number: 2007-S-029-01, Title: Home / Enterprise WiBro System Technology Development].

Wireless Broadband Internet (hereinafter referred to as WiBro or Portable Internet) is called Wireless High Speed Internet or 2.3 GHz Portable Internet.

WiBro is located between Wireless Local Area Network (WLAN) and mobile communication-based wireless internet, which guarantees mobility even though it is slower than wireless LAN, and does not guarantee high-speed mobility like mobile communication-based wireless Internet. It is an IP (Internet Protocol) based wireless data system that can provide Internet service at transmission speed.

In other words, it means a service that can access a variety of information and contents by accessing the Internet at a high speed even in a state of stopping and walking or moving at 60 km / h using a portable wireless terminal.

Such a WiBro allows all users connected to a base station to share a channel based on the IEEE 802.16d / e standard, and can efficiently use the channel by providing different quality services according to the characteristics of each user service. .

WiBro divides a channel into an uplink channel and a downlink channel, and assigns a TLV (Type, Length, Value) that defines uplink and downlink access information by the base station so that the user can divide the channel for each uplink and downlink frame. ), And included in the Uplink Channel Descriptor (UCD) message to the user periodically.

In addition, the frame of the WiBro system consists of a downlink subframe and an uplink subframe, wherein the downlink subframe includes a preamble, a map, and a downlink (DL) burst. The frame consists of a band AMC subchannel and a general subchannel.

In the WiBro system, the base station allocates a channel quality indicator channel (CQICH) to the terminal, and the terminal may transmit its channel state to the base station through the CQICH. That is, CQICH refers to a channel allocated to a terminal for reporting channel measurement information. After the UE measures and compares reception quality of a forward pilot channel received from a base station included in an active set, the result is measured. Reverse channel used for feedback.

The terminal may measure its channel information and transmit it to the base station through the CQICH. In this case, since the channel information is 6 bits, 64 code words are used. Among them, 32 codewords are used to report channel-to-interference noise ratio (CINR) of the channel to the base station, except for 25 codewords used for other purposes. Not defined

In the prior art, three codewords out of seven codewords not defined for transition between the general subchannel mode and the band AMC subchannel mode are defined as C1, C2, and C3, respectively.

First, C1 is defined as 0b111101 as a code word sent to the base station by the terminal to request a transition from the general subchannel mode to the band AMC subchannel mode.

C2 is defined as 0b111110 as a code word sent to the base station through a channel status report response (REP-RSP) message to confirm that the terminal has transmitted the information on the five best bands for the band AMC.

C3 is defined as 0b111111 as a code word sent to the base station by the terminal to transition from the band AMC subchannel mode to the general subchannel mode.

Hereinafter, an operation between a terminal and a base station for transition between a general subchannel mode and a band AMC mode using three codewords will be described with reference to FIGS. 1 and 2.

FIG. 1 is a flowchart illustrating a method for allocating a band AMC subchannel in a conventional WiBro system. Referring to FIG. 1, a UE transitions from a general subchannel mode to a band AMC subchannel mode.

First, the terminal 10 transmits C1 to the base station 20 through the CQICH in order to receive the band AMC subchannel (101).

Thereafter, the base station 20 receiving the C1 from the terminal 10 transmits a channel status report request (hereinafter, REP-REQ) message to the terminal 10 (102).

Subsequently, the terminal 10 receiving the REP-REQ message from the base station 20 receives a channel status report response (hereinafter referred to as REP-RSP) message including five band information having the best channel state and a codeword for informing the same. ) Is transmitted to the base station 20 (103). In this case, C2 is a codeword sent to confirm that the terminal 10 has transmitted information about five bands for band AMC to the base station 20 through a REP-RSP message.

Thereafter, the base station 20 receiving the REP-RSP message and the C2 from the terminal 10 allocates a band AMC subchannel to the terminal 10 (104).

Thereafter, the terminal 10 transmits a CINR difference value (Band AMC Differential CQI) of five bands having a good channel state to the base station (105).

The base station 20 received this increases by 1 dB when the CINR difference is 1, and decreases by 0 dB when the CINR difference is 0.

On the other hand, the process of changing the terminal A allocated the band AMC subchannel to another band AMC subchannel is the same as the process of transition from the general subchannel mode shown in Figure 1 to the band AMC subchannel mode.

In addition, the UE 10 may update the CINR values of the five bands without changing the band through the “103” process.

2 is a flowchart illustrating an exemplary method for allocating a general subchannel in a conventional WiBro system, and illustrates a process of a UE transitioning from a band AMC subchannel mode to a general subchannel mode.

First, the terminal 10 transmits C3 to the base station through the CQICH in order to release the band AMC subchannel allocation and transition to the general subchannel mode (201).

Instead of the CINR difference values for the five bands, the average CNR of the entire bands (Regular CQI of Whole Bandwith) is transmitted to the base station 20 (202).

At this time, the terminal 10 repeatedly transmits the average value of the CINR for the entire band C3 and the channel measurement information (CQI) until the base station 20 allocates the general subchannel (203, 204).

Thereafter, when the base station 20 allocates a general subchannel to the terminal 10, the terminal 10 transmits an average CINR value 206 for the entire band to the base station 20 through the CQICH. At this time, the terminal 10 changes the average CINR value for the entire band in 32 steps and encodes the data into 5 bits and transmits it.

Information of the UCD message field for transition between the conventional general subchannel mode and the band AMC subchannel is shown in Table 1 below.

The transition conditions between the general subchannel mode and the band AMC mode using the fields defined in [Table 1] are as follows.

end. Transition Condition from Normal Subchannel Mode to Band AMC Mode

In order to measure the average value and the standard deviation in the transition process from the general subchannel to the band AMC subchannel, the terminal is the maximum standard of the CINR measurement of each band of each band of the specific terminal during the time required (the value of the "Band AMC Allocation Timer" field). The deviation is less than the maximum threshold value of the standard deviation for each band-specific CINR measurement (the "Band AMC Allocation ThRSPhold" field value), and the average band-wide CINR value is the full-band average CINR value ("Band AMC Entry Average CINR" field). Value), the terminal requests the transition from the general subchannel to the band AMC subchannel by transmitting the C1 defined above to the base station through the CQICH.

I. Transition from Band AMC Mode to Normal Subchannel Mode

In order to measure the average value and the standard deviation in the transition process from the band AMC subchannel to the general subchannel, the mobile station is the maximum of the standard deviation of the CINR measurement value of each band during the time required (the value of the "Band AMC Release Timer" field). If the value is greater than the maximum threshold value of the standard deviation for each band CINR measurement value ("Band AMC Release ThRSPhold" field value), the UE transmits the C3 defined above to the base station through the CQICH, the band AMC subchannel The base station requests a transition to the general subchannel.

All. Band change

Except for the five bands selected for the band AMC assignment, the CINR values of the other bands are the time required for the UE to measure the mean and standard deviation during the transition from the normal subchannel to the band AMC subchannel. If it is larger than the average CINR of the entire band during the " Band AMC Allocation Timer " field value, the AMC allocation band is changed.

This prior art defines three codewords C1, C2, and C3 among CQICH codewords in a WiBro system, and provides the information of five bands having the best channel status to the base station in response to the channel status report. As the situation of the channel is good and the channel environment is hardly changed, there is a problem of reducing the flexibility of band allocation to the terminal when transitioning from the general subchannel to the band AMC subchannel due to the common preference of specific bands. have.

In addition, the conventional technology has a problem of increasing the overhead for reassignment when the terminals request a specific band allocation in duplicate.

It is a problem of the present invention to solve the problems of the prior art as described above.

Therefore, the present invention is a band AMC subchannel mode in the normal sub-channel mode without the overhead due to the reallocation of the band when the terminal prefers a particular AMC band in an environment where there is almost no change in the channel state, such as indoors SUMMARY OF THE INVENTION An object of the present invention is to provide a method for allocating a band AMC subchannel in a portable Internet system and a computer-readable recording medium having recorded thereon a program for realizing the method.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention which are not mentioned above can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. Also, it will be readily appreciated that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

According to an aspect of the present invention, there is provided a method for allocating a band AMC subchannel in a terminal, the method comprising: requesting a base station to transition to a band AMC mode; A band information transmitting step of transmitting a predetermined number of band information to the base station in order of worst state according to a channel state report request from the base station; A signal-to-interference noise ratio transmission step of transmitting a signal-to-interference noise ratio for the band allocated from the base station to the base station; And transmitting a difference value of a signal-to-interference noise ratio for a band allocated from the base station.

In addition, another method of the present invention for achieving the above object is, in the band AMC subchannel allocation method in the base station, the channel status requesting the channel status report to the terminal in response to the transition request from the terminal to the band AMC mode Report request step; Allocating a band from the currently unassigned bands other than the corresponding band to the terminal as the predetermined number of band information is transmitted from the terminal in the worst state; And a band transmission step of transmitting the allocated band to the terminal.

On the other hand, the present invention, the terminal having a processor, a function for requesting a transition to the band AMC mode to the base station; Transmitting a predetermined number of band information to the base station in order of worst state according to a channel state report request from the base station; Transmitting a signal-to-interference noise ratio for the band allocated from the base station to the base station; And a computer-readable recording medium having recorded thereon a program for realizing a function of transmitting a difference value of a signal-to-interference noise ratio for a band allocated from the base station.

In addition, the present invention, the base station having a processor, the function of requesting the channel status report to the terminal in response to a transition request from the terminal to the band AMC mode; A function of allocating an arbitrary band among the bands not currently allocated except for the band to the terminal as a predetermined number of band information is transmitted from the terminal in the worst state; And a computer readable recording medium having recorded thereon a program for realizing a function of transmitting the allocated band to the terminal.

In addition, the present invention, a function for receiving a signal-to-interference noise ratio for the allocated band from the terminal; And a computer readable recording medium having recorded thereon a program for realizing a function of receiving a difference value of a signal-to-interference noise ratio for the allocated band from the terminal.

Meanwhile, the present invention uses the worst five bands as CINR messages reported by the terminal when operating the band AMC in the indoor WiBro system, so that multiple terminals request the same band in the indoor WiBro system to perform the system performance. Solve the problem of deterioration.

The present invention also provides a method for requesting an AMC subchannel allocation to a base station by a base station and a terminal to transmit or receive data to the base station, wherein the terminal requests a transition from a general subchannel mode to a band AMC subchannel mode. Transmitting a first codeword to the base station through a channel measurement information channel (CQICH), and receiving a REP-REQ message from the base station, using a predetermined band having the worst channel state through a REP-RSP message. Transmitting a second codeword indicating that the information is transmitted to the base station; and receiving a band allocated to the terminal through the REP-REQ message from the base station, and receiving the band from the allocated band through the REP-RSP message. Transmitting, to the base station, a fourth codeword indicating a signal-to-interference noise ratio and transmitting the information; A forward information channel the variation of signal-to-interference ratio for the band continuously through comprises a process of sending to the base station.

As described above, the present invention provides a band AMC in a general subchannel mode without overhead due to reallocation of a band when the UEs prefer a specific AMC band in an environment in which there is little change of channel state and indoor mobility, such as indoors. There is an effect that the transition to the sub-channel mode can be efficiently.

In addition, in the present invention, when the UE operates in the band AMC mode, since the bands preferred by most UEs are similar, the overhead thereof may be increased and the yield of the system may be lowered. In fact, the band allocated to each terminal is selected by the base station, thereby increasing the flexibility of band allocation and increasing the overall yield of the system.

The above objects, features, and advantages will become more apparent from the detailed description given hereinafter with reference to the accompanying drawings, and accordingly, those skilled in the art to which the present invention pertains may share the technical idea of the present invention. It will be easy to implement. In addition, in describing the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In an embodiment of the present invention will be described taking a portable Internet system, a so-called WiBro system as an example.

In addition, in the present invention, for efficient band allocation in the band AMC subchannel mode, a conventional codeword C2 is newly defined, and in addition, a codeword called C4 is defined.

The C1 codeword transmits its channel information to the base station in order for the terminal to transition from the general subchannel mode to the band AMC subchannel mode, as in the conventional definition.

The C2 codeword is a codeword for confirming that the terminal transmits five worst bands through a REP-RSP message to the base station.

The C4 codeword is a codeword for confirming that the terminal transmits CINR measurement values for five bands received from the base station through a REP-RSP message.

Table 2 below shows the definition of each TLV field of the REP-REQ message according to the present invention, which is based on the "802.16e standard".

As shown in [Table 2], the base station adds a "Worst band report type" field and a "Band AMC report" field to the conventional REP-REQ message, so that the base station requests the bitmap information of the worst band to the terminal and assigns the terminal to the terminal. Enable bitmap information delivery for five bands to be performed.

Referring to [Table 2], the base station receiving the C1 codeword to transition from the general subchannel mode to the band AMC subchannel mode from the terminal, writes "CINR report" in the value of the "Report type" field, " Channel “Request Type” is written in “Band AMC Channel” and “Worst band report” is in “Worst band report”. The REP-REQ message is sent to the UE. Allows you to transition to band AMC subchannel mode.

In addition, the base station receiving the C2 codeword confirming that five worst-case bands are transmitted from the terminal through the REP-RSP message, writes the “CINR report” in the value of the “Report type” field, and the “Channel Type request” field. Write “Band AMC Channel” in the value of, write “CINR report” in the value of the “Worst band report type” field, and band except five worst bands received from the terminal in the value of the “Band AMC report” field. The five selected bands are transmitted to the terminal through a REP-REQ message in the form of a bitmap, so that the terminal can transition from the general subchannel mode to the band AMC subchannel mode.

Table 3 below shows the definition of each TLV field of the REP_RSP message according to the present invention, which is based on the "802.16e standard".

In [Table 3], the UE newly defines a field according to the value of the “Worst band report type” field of the REP-RSP message in the REP-RSP message, so that the UE transmits bitmap information about the worst band to the base station and is allocated a band. Enables transmission of bitmap information and CINR measurements of the band.

Referring to [Table 3], when a UE that transmits a C1 codeword to transition from a general subchannel mode to a band AMC subchannel mode receives a REP-REQ message from a base station, the terminal transmits a field value of type “7.1”. By transmitting a REP-RSP message using bitmap information of five worst-case bands to the base station, a limitation can be applied when the base station allocates a band to the terminal.

In addition, when the terminal transmitting the REP-RSP message receives the REP-REQ message indicating the five bands allocated from the base station, bitmap information on the five bands allocated to the value of the field “7.2” and Sending a REP-RSP message with the CINR measurement for the base station to enable the base station to know the CINR value for the band.

3 is a flowchart illustrating a method for allocating a band AMC subchannel in a portable Internet system according to the present invention, and illustrates a process for a terminal to transition from a general subchannel mode to a band AMC mode.

First, in order to transition from the general subchannel mode to the band AMC mode, the terminal 10 transmits a C1 codeword requesting a transition to the band AMC mode to the base station 20 (301).

Thereafter, the base station 20 receiving the C1 codeword transmits a REP-REQ message requesting a channel status report to the terminal 10 (302).

Subsequently, the terminal 10 receiving the REP-REQ message transmits the five bands having the worst state to the base station 20 in the REP-RSP message, and together with the REP- carrying five bands having the worst state. The C2 codeword confirming transmission of the RSP message is transmitted to the base station 20 (303). At this time, the five worst bands are transmitted in the form of a bitmap.

Subsequently, the base station 20 receiving the REP-RSP message and the C2 codeword allocates any five bands among the bands not currently allocated to the terminal 10 except for the five bands in the worst state. 304).

Thereafter, the allocated five bands are transmitted to the terminal 10 in a bitmap form through a REP-REQ message (305).

Thereafter, the terminal 10 receiving the REP-REQ message containing the five bands transmits the CINR measurement values for the five bands to the base station 20 in the REP-RSP message, and together with the five bands. The C4 codeword confirming transmission of the REP-RSP message containing the CINR measurement for the UE is transmitted to the base station 20 (306).

Thereafter, the terminal 10 periodically transmits CQI difference values for the five bands allocated from the base station 20, so that the base station 20 can know the state information for the currently allocated band (307).

Here, the process that the terminal 10 operating in the band AMC mode should be performed to receive another band AMC subchannel is performed in order for the terminal 10 operating in the general subchannel mode to transition to the band AMC subchannel mode. It is the same as the process shown in FIG.

On the other hand, the method of the present invention as described above can be written in a computer program. And the code and code segments constituting the program can be easily inferred by a computer programmer in the art. In addition, the written program is stored in a computer-readable recording medium (information storage medium), and read and executed by a computer to implement the method of the present invention. The recording medium may include any type of computer readable recording medium.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

The present invention can be used for a portable internet system and the like.

1 is a flowchart illustrating a method for allocating a band AMC subchannel in a conventional WiBro system;

2 is a flowchart illustrating a general subchannel allocation method in a conventional WiBro system;

3 is a flowchart illustrating a method for allocating a band AMC subchannel in a portable Internet system according to the present invention.

* Explanation of symbols for the main parts of the drawings

10: terminal 20: base station

Claims (13)

In the band AMC subchannel allocation method in the terminal, Requesting the base station to transition to the band AMC mode; A band information transmitting step of transmitting a predetermined number of band information to the base station in order of worst state according to a channel state report request from the base station; A signal-to-interference noise ratio transmission step of transmitting a signal-to-interference noise ratio for the band allocated from the base station to the base station; And Transmitting a difference value of a signal-to-interference noise ratio for a band allocated from the base station Band AMC subchannel allocation method in a terminal comprising a. The method of claim 1, The band information transmission step, And transmitting the band information in the form of a bitmap to the base station. The method according to claim 1 or 2, The band information transmission step, And transmitting the first codeword indicating that the band information is in the worst ordered band together with the band information to the base station. The method of claim 3, wherein The signal-to-interference noise ratio transmission step, And a second codeword indicating a signal-to-interference noise ratio for the band allocated from the base station to the base station together with the signal-to-interference noise ratio. The method of claim 4, wherein The band information, A band AMC subchannel allocation method in a terminal characterized by five individuals. In the band AMC subchannel allocation method in the base station, A channel status report requesting step of requesting a channel status report to the terminal according to a transition request from the terminal to the band AMC mode; Allocating a band from the currently unassigned bands other than the corresponding band to the terminal as the predetermined number of band information is transmitted from the terminal in the worst state; And A band transmission step of transmitting the allocated band to the terminal Band AMC subchannel allocation method in a base station comprising a. The method of claim 6, Receiving a signal-to-interference noise ratio for the allocated band from the terminal; And Receiving a difference value of a signal-to-interference noise ratio for the allocated band from the terminal Band AMC subchannel allocation method in the base station further comprising. The method according to claim 6 or 7, The channel status report request step, REP with “CINR report” in the “Report type” field, “Band AMC Channel” in the value in the “Channel Type request” field, and “Worst band report” in the value in the “Worst band report type” field. The method of band AMC subchannel allocation in a base station characterized in that the request is made through a -REQ message. The method of claim 8, The band transmission step, Write “CINR report” in the “Report type” field, “Band AMC Channel” in the “Channel Type request” field, “CINR report” in the “Worst band report type” field, and “ Band AMC subchannel allocation method in the base station, characterized in that the transmission of the five bands except the five bands received from the terminal through the REP-REQ message to the value of the "band AMC report" field value; . The method according to claim 6 or 7, The band transmission step, And transmitting the allocated band in the form of a bitmap. In a terminal equipped with a processor, Requesting the base station to transition to the band AMC mode; Transmitting a predetermined number of band information to the base station in order of worst state according to a channel state report request from the base station; Transmitting a signal-to-interference noise ratio for the band allocated from the base station to the base station; And A function of transmitting a difference value of the signal-to-interference noise ratio for the band allocated from the base station A computer-readable recording medium having recorded thereon a program for realizing this. A base station equipped with a processor, Requesting a channel status report to the terminal according to a transition request from the terminal to the band AMC mode; A function of allocating an arbitrary band among the bands not currently allocated except for the band to the terminal as a predetermined number of band information is transmitted from the terminal in the worst state; And Sending the allocated band to the terminal A computer-readable recording medium having recorded thereon a program for realizing this. The method of claim 12, Receiving a signal-to-interference noise ratio for the allocated band from the terminal; And A function for receiving a difference value of the signal-to-interference noise ratio for the allocated band from the terminal A computer-readable recording medium that records a program for further realization.

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