Patent Description:
As wireless communication systems advance, service type expansion and high service quality are demanded. In this regard, a broadband wireless communication system is introduced recently.

The broadband wireless communication system utilizes a limited frequency band. Accordingly, to provide broadband services, the broadband wireless communication system requires additional available frequency band. For example, in a wireless communication system of Institute of Electrical and Electronics Engineers (IEEE) <NUM> standard, a Base Station (BS) manages at least one Frequency Assignment (FA). The BS provides the wireless communication service to a Mobile Station (MS) over its managed FA.

Document <CIT> (Appl. No. <NUM>/<NUM>,<NUM>) describes a method for performing fast base station switching in an mobile station capable of using multiple frequency assignments in a wireless communication system, in which initial network entry to a base station managing at least two frequency assignments is performed in one of the at least two frequency assignments, overlay mode support information and FA information about the at least two frequency assignments are acquired by the initial network entry, the overlay mode support information indicating whether the base station supports multiple frequency assignments, the base station is notified that the mobile station will operate in an overlay mode using multiple frequency assignments based on the acquired information, and signals are transmitted and received to and from the base station in the at least two frequency assignments.

Document <CIT> describes a method and arrangements where each frequency channel is assigned a primary (global) number and a secondary (in-band) number. The primary number for one frequency channel (e.g. unicast downlink channel) and one or more secondary channel numbers to account for the corresponding unicast uplink and/or for one or more MBSFN channels are signaled. The primary (global) number indicates the band and frequency channel number while the secondary (in-band) number indicates the frequency channel within the relevant frequency band.

<FIG> depict configuration according to the number of frequency bands supported in the wireless communication system.

<FIG> depicts one FA managed by the BS, and <FIG> depicts two FAs managed by the BS.

As shown in <FIG>, the MS <NUM> can migrate from an FA1 zone <NUM> to an FA2 zone <NUM>. Herein, the FA1 zone <NUM> indicates service coverage using the FA1 and the FA2 zone <NUM> indicates service coverage using the FA2. For example, when the MS <NUM> travels in the FA1 zone <NUM>, the MS <NUM> operates only one FA (e.g., FA1). When the FA1 and the FA2 are managed by different BSs, the MS <NUM> may use the wireless communication service using the FA2 after handover between the FAs.

In <FIG>, it is assumed that the MS <NUM> and the BS can manage at least two FAs. The MS <NUM> can receive the wireless communication service using both of the FA1 zone <NUM> and the FA2 zone <NUM>. When the MS and the BS transmit and receive signals over the multiple FAs as above, the MS and the BS can transmit and receive high-capacity data at a high data rate.

When the MS uses a plurality of the FAs at the same time, the FAs used by the MS can be configured asymmetrically as shown in <FIG>.

<FIG> depict asymmetric frequency band configuration in a wireless communication system supporting multiple bands.

In <FIG>, the FA1 <NUM> is used to transmit UpLink (UL) data, the FA2 <NUM> is used to transmit DownLink (DL) data, and the FA3 <NUM> is used to transmit UL data and DL data. That is, the FA1 <NUM> and the FA2 <NUM> indicate the FAs supporting a Frequency Division Duplex (FDD) structure, and the FA3 <NUM> indicates the FA supporting a Time Division Duplex (TDD) structure. When the FA2 <NUM> and the FA3 <NUM> are allocated to the MS <NUM>, the MS <NUM> has an asymmetric carrier aggregation which receives a DL signal using DL regions of the FA2 <NUM> and the FA3 <NUM> and transmitting a UL signal using a UL region of the FA3 <NUM>.

In <FIG>, the FA1 <NUM>, the FA2 <NUM>, and the FA3 <NUM> are used to transmit UL data and DL data. Namely, the FA1 <NUM>, the FA2 <NUM>, and the FA3 <NUM> indicate FAs supporting the TDD structure.

When the DL region of the FA1 <NUM> and the FA2 <NUM> are allocated to the MS <NUM>, the MS <NUM> has the asymmetric carrier aggregation which receives a DL signal using the DL regions of the FA1 <NUM> and the FA2 <NUM> and transmitting a UL signal using the UL region of the FA2 <NUM>.

In <FIG>, the FA1 <NUM> is used to transmit DL data, the FA2 <NUM> is used to transmit UL data and DL data, and the FA3 <NUM> is used to transmit UL data. That is, the FA1 <NUM> and the FA3 <NUM> indicate FAs supporting the FDD structure, and the FA2 <NUM> indicates an FA supporting the TDD structure.

When the FA1 <NUM>, the DL region of the FA2 <NUM>, and the FA3 <NUM> are allocated to the MS <NUM>, the MS has the asymmetric carrier aggregation which receives a DL signal using the FA1 <NUM> and the DL region of the FA2 <NUM> and transmitting a UL signal using the FA3 <NUM>.

The BS in the wireless communication system allocates resource to the MS to provide the service using channel feedback information received from the MS. However, in the asymmetric carrier aggregation, there can be no UL channel symmetrical to the DL channel. In this regard, what is needed a separate method for transmitting the channel feedback information between the BS and the MS in the asymmetric carrier aggregation.

An aspect of the present invention is to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide an apparatus and a method for communicating between a terminal and a base station using an asymmetric frequency band in a wireless communication system, as claimed in claims <NUM>, <NUM>, <NUM>, <NUM>.

It is noted that a asymmetric frequency band indicates a frequency band supporting only one of a downlink and an uplink, and a symmetric frequency band indicates a frequency band supporting both of the downlink and the uplink.

Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

Throughout the drawings, like reference numerals will be understood to refer to like parts, components and structures.

The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the present invention as defined by the claims. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention is provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims.

<FIG>, discussed below, and the various exemplary embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way that would limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged communications system. The terms used to describe various embodiments are exemplary. It should be understood that these are provided to merely aid the understanding of the description, and that their use and definitions in no way limit the scope of the invention. Terms first, second, and the like are used to differentiate between objects having the same terminology and are in no way intended to represent a chronological order, unless where explicitly state otherwise. A set is defined as a non-empty set including at least one element.

Exemplary embodiments of the present invention provide a technique for transmitting feedback information when data is transmitted and received using an asymmetric frequency band in a wireless communication system which utilizes multiple bands.

Hereinafter, Orthogonal Frequency Division Multiplexing (OFDM)/Orthogonal Frequency Division Multiple Access (OFDMA) wireless communication system is exemplified. Note that the present invention is equally applicable to other wireless communication systems.

Hereafter, a mode of a Mobile Station (MS) and a Base Station (BS) for transmitting and receiving signals over a plurality of frequency bands is referred to as an overlay mode. A wireless communication system in the overlay mode is referred to as an overlay wireless communication system.

In the overlay mode using an asymmetric Secondary Frequency Assignment (S-FA) as shown in <FIG>, the MS needs to provide feedback with respect to the asymmetric S-FA, in addition to a primary band. The BS should indicate resources of the Primary-FA (P-FA) required to transmit the feedback of the asymmetric S-FA. For example, using the asymmetric carrier aggregation of <FIG>, the BS should indicate resources of the P-FA required to transmit the feedback of the asymmetric FA2 <NUM>. The MS needs to transmit the feedback of the asymmetric FA2 <NUM> to the BS according to the instruction of the BS.

Now, a frame for the MS to transmit the feedback for the asymmetric S-FA is explained.

<FIG> illustrates a frame for transmitting the feedback of the asymmetric frequency band in a wireless communication system according to one exemplary embodiment of the present invention.

As shown in <FIG>, a P-FA1 <NUM> includes a DownLink (DL) region <NUM> and an UpLink (UL) region <NUM>. A S-FA <NUM> includes a DL region <NUM>. That is, the P-FA1 <NUM> is configured in a Time Division Duplex (TDD) manner.

The DL region <NUM> of the P-FA1 <NUM> includes a Super Frame Header (SFH) <NUM>, DL resource allocation MAP information (DL assignment A-MAP IE) <NUM>, UL resource allocation MAP information (UL assignment A-MAP IE) <NUM>, fast feedback allocation MAP information (fast feedback allocation A-MAP IE) <NUM>, and feedback poling MAP information (feedback polling A-MAP IE) <NUM>. Herein, the fast feedback allocation MAP information <NUM> and the feedback polling MAP information <NUM>, which are described to ease the understanding of the present invention, may not be contained in the DL region <NUM> of the P-FA1 <NUM>.

The DL region <NUM> of the S-FA <NUM> includes an SFH <NUM>, DL resource allocation MAP information <NUM>, fast feedback allocation MAP information <NUM>, and feedback polling MAP information <NUM>. Herein, the fast feedback allocation MAP information <NUM> and the feedback polling MAP information <NUM>, which are described to ease the understanding of the present invention, may not be contained in the DL region <NUM> of the S-FA <NUM>.

The UL region <NUM> of the P-FA1 <NUM> includes feedback channel <NUM> for the DL of the P-FA1 <NUM> (DLRUs for feedback channels of primary carrier, DLRUs: Distributed Logical Resource Units), Band Request (BR) channel <NUM> of the P-FA1 <NUM> (BR channel of primary carrier), feedback channel <NUM> for DL of the S-FA <NUM> (DLRUs for feedback channels of secondary carrier), data channel <NUM> of the P-FA1 <NUM> (data channel for primary carrier), data channel <NUM> for transmitting fast feedback information of the P-FA1 <NUM> (data channel (MAC control message) for primary carrier), and data channel <NUM> for transmitting fast feedback information of the S-FA <NUM> (data channel (MAC control message) for secondary carrier).

In such a frame, the DL feedback channel information <NUM> of the P-FA1 <NUM> is transmitted through the SFH <NUM> of the P-FA1 <NUM>, and the DL feedback channel information <NUM> of the S-FA <NUM> is transmitted through the SFH <NUM> of the S-FA <NUM>. The data channel information <NUM> for transmitting the fast feedback information of the P-FA1 <NUM> is transmitted through the feedback polling MAP information <NUM> of the P-FA1 <NUM>, and the data channel information <NUM> for transmitting the fast feedback information of the S-FA <NUM> is transmitted through the feedback polling MAP information <NUM> of the S-FA <NUM>. For example, the feedback channel information transmitted using the SFHs <NUM> and <NUM> includes information of Table <NUM>.

In Table <NUM>, the SFHs <NUM> and <NUM> include entire feedback channel region information (number of Distributed LRUs for UL feedback channel per a UL AAI subframe), and HARQ feedback transmission channel region information (number of UL ACK/NACK channels per HARQ feedback region) in the feedback channel region. For example, the SFH <NUM> of the P-FA1 <NUM> includes the entire feedback channel region information of the P-FA1 <NUM>, and the HARQ feedback transmission channel region information of the feedback channel region. For example, the SFH <NUM> of the S-FA <NUM> includes the entire feedback channel region information of the S-FA <NUM>, and the HARQ feedback transmission channel region information of the feedback channel region. Herein, the entire feedback channel region includes information combining the HARQ feedback transmission channel region and the fast feedback channel region. Accordingly, the MS can obtain the fast feedback channel region information using the entire feedback channel region information and the HARQ feedback transmission channel region information. The feedback channel region <NUM> for the S-FA <NUM> follows the BR channel <NUM>. Hence, the SFH <NUM> of the S-FA <NUM> does not need to contain start information of the feedback channel region <NUM> for the S-FA <NUM>.

When a plurality of MSs supports a Carrier Aggregation (CA) mode of the overlay mode, the P-FA of each MS can be defined differently. Thus, the P-FA of a particular MS can be the S-FA of other MS.

Alternatively, the P-FAs of the MSs supporting the overlay mode can be defined differently and their S-FAs can be set to the same FA. In this case, the S-FA can be an asymmetric band including only the DL, such as FA2 <NUM> of <FIG>.

Alternatively, the P-FAs of the MSs supporting the overlay mode can be set to the same FA and their S-FAs can be defined differently. At this time, the S-FA can be an asymmetric band including only the DL, such as FA2 <NUM> of <FIG>.

When the MSs operating in the overlay mode share the S-FA and utilize the different P-FAs as stated above, a frame for transmitting the feedback for the asymmetric S-FA can be configured as shown in <FIG>. For example, the frame of <FIG> can be used as well when the MSs share the P-FA and utilize different S-FAs.

<FIG> illustrates a frame for transmitting the feedback of the asymmetric frequency band in the wireless communication system according to another exemplary embodiment of the present invention.

In <FIG>, a P-FA1 <NUM> includes a DL region <NUM> and a UL region <NUM>, an S-FA <NUM> includes a DL region <NUM>, and a P-FA2 <NUM> includes a DL region <NUM> and a UL region <NUM>. That is, the P-FA1 <NUM> and the P-FA2 <NUM> are configured in the TDD manner.

The DL region <NUM> of the P-FA1 <NUM> includes an SFH <NUM>, DL resource allocation MAP information <NUM>, UL resource allocation MAP information <NUM>, fast feedback allocation MAP information <NUM>, and feedback polling MAP information <NUM>. Herein, the fast feedback allocation MAP information <NUM> and feedback polling MAP information <NUM>, which are described to ease the understanding of the present invention, may not be contained in the DL region <NUM> of the P-FA1 <NUM>.

The UL region <NUM> of the P-FA1 <NUM> includes a feedback channel <NUM> for the DL of the P-FA1 <NUM>, a BR channel <NUM> of the P-FA1 <NUM>, a feedback channel <NUM> for the DL of the S-FA <NUM>, a data channel <NUM> of the P-FA1 <NUM>, a data channel <NUM> for transmitting fast feedback information of the P-FA1 <NUM>, and a data channel <NUM> for transmitting fast feedback information of the S-FA <NUM>. Herein, the feedback channel <NUM> and the data channel <NUM> for transmitting the fast feedback information of the P-FA1 <NUM> utilize the P-FA1 <NUM> and the S-FA <NUM>, and are information corresponding to the MS operating in the overlay mode.

The DL region <NUM> of the P-FA2 <NUM> includes an SFH <NUM>, DL resource allocation MAP information <NUM>, UL resource allocation MAP information <NUM>, fast feedback allocation MAP information <NUM>, and feedback polling MAP information <NUM>. Herein, the fast feedback allocation MAP information <NUM> and the feedback polling MAP information <NUM>, which are described to ease the understanding of the present invention, may not be contained in the DL region <NUM> of the P-FA2 <NUM>.

The UL region <NUM> of the P-FA2 <NUM> includes a feedback channel <NUM> for the DL of the P-FA2 <NUM>, a BR channel <NUM> of the P-FA2 <NUM>, a feedback channel <NUM> for the DL of the S-FA <NUM>, a data channel <NUM> of the P-FA2 <NUM>, a data channel <NUM> for transmitting fast feedback information of the P-FA2 <NUM>, and a data channel <NUM> for transmitting fast feedback information of the S-FA <NUM>. Herein, the feedback channel <NUM> and the data channel <NUM> for transmitting the fast feedback information of the P-FA2 <NUM> utilize the P-FA2 <NUM> and the S-FA <NUM>, and are information corresponding to the MS operating in the overlay mode.

In this frame, the DL feedback channel information <NUM> of the P-FA1 <NUM> is transmitted through the SFH <NUM> of the P-FA1 <NUM>, and the DL feedback channel information <NUM> of the S-FA <NUM> is transmitted through the SFH <NUM> of the S-FA <NUM>. The data channel information <NUM> for transmitting the fast feedback information of the P-FA1 <NUM> is transmitted through the feedback polling MAP information <NUM> of the P-FA1 <NUM>, and the data channel information <NUM> for transmitting the fast feedback information of the S-FA <NUM> is transmitted through the feedback polling MAP information <NUM> of the S-FA <NUM>.

The feedback channel information transmitted through the SFH <NUM> of the P-FA1 <NUM> includes the information of Table <NUM>.

The DL feedback channel information <NUM> of the P-FA2 <NUM> is transmitted through the SFH <NUM> of the P-FA2 <NUM>, and the DL feedback channel information <NUM> of the S-FA <NUM> is transmitted through the SFH <NUM> of the S-FA <NUM>. The data channel information <NUM> for transmitting the fast feedback information of the P-FA2 <NUM> is transmitted through the feedback polling MAP information <NUM> of the P-FA2 <NUM>, and the data channel information <NUM> for transmitting the fast feedback information of the S-FA <NUM> is transmitted through the feedback polling MAP information <NUM> of the S-FA <NUM>.

The feedback channel information transmitted using the SFH <NUM> of the P-FA2 <NUM> includes the information of Table <NUM>.

To carry information relating to the feedback channel <NUM> using the P-FA1 <NUM> and the feedback channel <NUM> using the P-FA2 <NUM>, the SFH <NUM> of the S-FA <NUM> includes information of Table <NUM>.

In Table <NUM>, the SFH <NUM> of the asymmetric S-FA <NUM> includes a carrier index for the P-FA of the MSs which use the asymmetric S-FA <NUM>, entire feedback channel region information (number of Distributed LRUs for UL feedback channel per a UL AAI subframe) for the S-FA <NUM> of the MSs allocated in each P-FA, and HARQ feedback transmission channel region information (number of UL ACK/NACK channels for HARQ feedback region) of the feedback channel region. Herein, the entire feedback channel region includes information combining the HARQ feedback transmission channel region and the fast feedback channel region. Accordingly, the MS can obtain the fast feedback channel region information using the entire feedback channel region information and the HARQ feedback transmission channel region information.

The SFH <NUM> of the S-FA <NUM> in Table <NUM> can include feedback channel region start (the start LRUs index for feedback channel) information. The feedback channel region start information informs where the feedback channel region for the S-FA <NUM> starts from. However, when the feedback channel region follows the BR channel <NUM> and <NUM>, the SFH <NUM> does not need to contain the feedback channel region start information.

Following explanations describe a method of the MS for processing the feedback of the asymmetric S-FA using the frame of <FIG> or <FIG>.

<FIG> illustrates a method for processing the feedback of the asymmetric frequency band at the MS in the wireless communication system according to an exemplary embodiment of the present invention.

The MS which is communicating with the BS using the P-FA determines whether to enter the CA mode of the overlay mode in step <NUM>.

Not entering the CA mode, the MS finishes this process.

When entering the CA mode, the MS transmits its multiple frequency support capability (multicarrier capability) information to the BS in step <NUM>. Herein, the multiple frequency support capability information includes frequency bands supportable by the MS, the number of the frequency bands operable by the MS concurrently, and guard subcarrier support.

In step <NUM>, the MS receives information of the S-FA to use in the CA mode, from the BS.

In step <NUM>, the MS receives activation indication information for the S-FA from the BS. For example, the MS receives from the BS, the activation indication information for the UL/DL of the S-FA or the activation indication information for the DL.

In step <NUM>, the MS transmits and receives data to and from the BS in the CA mode using the S-FA activated as instructed by the BS and the P-FA.

As transmitting and receiving data in the CA mode, the MS determines whether the S-FA is the asymmetric frequency band in step <NUM>. For example, the MS checks whether the S-FA is the asymmetric frequency band using characteristic information of the frequency band contained in at least one of a global carrier configuration (AAI_Global-Config) message, a multiple frequency band information (AAI_MC-ADV) message, and a neighbor BS information (AAI_NBR-ADV) message which are received from the BS. Based on symmetric frequency band (fully configured carrier)/asymmetric frequency band (partially configured carrier) information of the frequency band characteristics, the MS checks whether the S-FA is the asymmetric frequency band. Alternatively, the MS may check whether the S-FA is the asymmetric frequency band, using the activation indication information for the S-FA received from the BS in step <NUM>. That is, when the BS instructs to activate only the DL of the S-FA, the MS recognizes that the S-FA is the asymmetric frequency band.

When the S-FA is the asymmetric frequency band, the MS obtains the feedback channel information for the asymmetric S-FA, from the SFH of the S-FA in step <NUM>. For example, referring back to <FIG>, the MS obtains the feedback channel information <NUM> for the DL of the S-FA <NUM>, from the SFH <NUM> of the S-FA <NUM>. The MS obtains the information of the data channel information <NUM> for transmitting the fast feedback information of the S-FA <NUM>, from the feedback polling MAP information <NUM> of the S-FA <NUM>. using the P-FA1 <NUM> of <FIG>, the MS may obtain the feedback channel information <NUM> for the DL of the S-FA <NUM>, from the SFH <NUM> of the S-FA <NUM>. The MS may obtain the information of the data channel <NUM> for transmitting the fast feedback information of the S-FA <NUM>, from the feedback polling MAP information <NUM> of the S-FA <NUM>.

In step <NUM>, the MS confirms the feedback channel region of the S-FA allocated to the UL region of the P-FA, using the feedback channel information of the S-FA. Next, the MS performs the feedback of the S-FA over the confirmed feedback channel region of the S-FA. For example, in <FIG>, the MS transmits the feedback of the P-FA over the feedback channel <NUM> of the P-FA <NUM> and transmits the feedback of the S-FA over the feedback channel <NUM> of the S-FA <NUM>.

When the S-FA is not the asymmetric frequency band in step <NUM>, the MS obtains the feedback channel information of the symmetric S-FA, from the SFH of the S-FA in step <NUM>.

In step <NUM>, the MS confirms the feedback channel region of the S-FA allocated in the UL region of the S-FA. Next, the MS performs the feedback of the S-FA over the confirmed feedback channel region of the S-FA.

<FIG> illustrates a method for processing the feedback of the asymmetric frequency band at the BS in the wireless communication system according to an exemplary embodiment of the present invention.

In step <NUM>, the BS checks whether the serviced MSs include the MS operating in the CA mode.

When there is no MS operating in the CA mode, the BS finishes this process.

When there is an MS operating in the CA mode, the BS checks whether there is an MS managing the asymmetric S-FA in step <NUM>.

When an MS manages the asymmetric S-FA, the BS transmits the feedback channel allocation information of the P-FA and the feedback channel allocation information for the asymmetric S-FA using the SFH of the P-FA and the SFH of the S-FA in step <NUM>. For example, in <FIG>, the BS transmits the feedback channel information <NUM> for the DL of the P-FA <NUM> using the SFH <NUM> of the P-FA <NUM>. The BS also transmits the feedback channel information <NUM> for the DL of the S-FA <NUM> using the SFH <NUM> of the S-FA <NUM>. The BS may transmit the information of the data channel <NUM> for transmitting the fast feedback information of the S-FA <NUM> using the feedback polling MAP information <NUM> of the S-FA. For instance, when the MS uses the P-FA1 <NUM> in <FIG>, the BS transmits the feedback channel information <NUM> for the DL of the P-FA1 <NUM> using the SFH <NUM> of the P-FA1 <NUM>. The BS transmits the feedback channel <NUM> information for the DL of the S-FA <NUM> using the SFH <NUM> of the S-FA <NUM>. In so doing, the BS may transmit the information of the data channel <NUM> for transmitting the fast feedback information of the S-FA <NUM> using the feedback polling MAP information <NUM> of the S-FA <NUM>.

In step <NUM>, the BS receives the feedback for the P-FA and the asymmetric S-FA over the feedback channel allocated in the UL region of the P-FA according to the feedback channel allocation information sent over the SFHs of the P-FA and the S-FA.

Meanwhile, when there is no MS managing the asymmetric S-FA in step <NUM>, the BS transmits the feedback channel allocation information of the symmetric S-FA using the SFH of the S-FA in step <NUM>. The BS transmits the feedback channel allocation information of the P-FA using the SFH of the symmetric P-FA.

In step <NUM>, the BS receives the feedback of the P-FA over the feedback channel allocated in the P-FA according to the feedback channel allocation information sent over the SFH of the P-FA. The BS also receives the feedback of the S-FA over the feedback channel allocated in the S-FA according to the feedback channel allocation information sent over the SFH of the symmetric S-FA.

In this exemplary embodiment, the BS transmits the feedback information of the asymmetric frequency band to the MS using the SFH.

Alternatively, the BS may transmit the feedback information of the asymmetric frequency band to the MS using a system channel information (AAI_SCD) message. A frame for the MS to transmit the feedback for the asymmetric S-FA can be constituted as shown in <FIG>.

<FIG> illustrates a frame for transmitting feedback of the asymmetric frequency band in the wireless communication system according to yet another exemplary embodiment of the present invention.

In <FIG>, the P-FA1 <NUM> includes a DL region <NUM> and a UL region <NUM> and the S-FA <NUM> includes a DL region <NUM>. That is, the P-FA1 <NUM> is configured in the TDD manner.

The DL region <NUM> of the S-FA <NUM> includes an SFH <NUM>, DL resource allocation MAP information <NUM>, fast feedback allocation MAP information <NUM>, feedback polling MAP information <NUM>, and system channel information (AAI_SCD) <NUM>. Herein, the fast feedback allocation MAP information <NUM> and the feedback polling MAP information <NUM>, which are described to ease the understanding of the present invention, may not be contained in the DL region <NUM> of the S-FA <NUM>.

The UL region <NUM> of the P-FA1 <NUM> includes a feedback channel <NUM> for the DL of the P-FA1 <NUM>, a BR channel <NUM> of the P-FA1 <NUM>, a feedback channel <NUM> for the DL of the S-FA <NUM>, a data channel <NUM> of the P-FA1 <NUM>, a data channel <NUM> for transmitting fast feedback information of the P-FA1 <NUM>, and a data channel <NUM> for transmitting fast feedback information of the S-FA <NUM>.

In this frame, the DL feedback channel information <NUM> of the P-FA1 <NUM> is transmitted through the SFH <NUM> of the P-FA1 <NUM>, and the DL feedback channel information <NUM> of the S-FA <NUM> is transmitted through the system channel information <NUM> of the S-FA <NUM>. The data channel information <NUM> for transmitting the fast feedback information of the P-FA1 <NUM> is transmitted through the feedback polling MAP information <NUM> of the P-FA1 <NUM>, and the data channel information <NUM> for transmitting the fast feedback information of the S-FA <NUM> is transmitted through the feedback polling MAP information <NUM> of the S-FA <NUM>. For example, the system channel information <NUM> includes the information of Table <NUM> or Table <NUM>.

Now, a method of the MS for processing the feedback of the asymmetric S-FA using the frame of <FIG> is elucidated.

<FIG> illustrates a method of the MS for processing the feedback of the asymmetric frequency band in the wireless communication system according to another exemplary embodiment of the present invention.

The MS which is communicating with the BS over the P-FA determines whether to enter the CA mode of the overlay mode in step <NUM>.

When entering the CA mode, the MS transmits its multiple frequency support capability information to the BS in step <NUM>. Herein, the multiple frequency support capability information includes frequency bands supportable by the MS, the number of the frequency bands operable by the MS concurrently, and guard subcarrier support.

As transmitting and receiving data in the CA mode, the MS determines whether the S-FA is the asymmetric frequency band in step <NUM>. For example, the MS checks whether the S-FA is the asymmetric frequency band using characteristic information of the frequency band contained in at least one of the global carrier configuration (AAI_Global-Config) message, the multiple frequency band information (AAI_MC-ADV) message, and the neighbor BS information (AAI_NBR-ADV) message which are received from the BS. Based on the symmetric frequency band (fully configured carrier)/asymmetric frequency band (partially configured carrier) information of the frequency band characteristics, the MS checks whether the S-FA is the asymmetric frequency band. Alternatively, the MS may check whether the S-FA is the asymmetric frequency band, using the activation indication information for the S-FA received from the BS in step <NUM>. That is, when the BS instructs to activate only the DL of the S-FA, the MS recognizes that the S-FA is the asymmetric frequency band.

When the S-FA is the asymmetric frequency band, the MS obtains the feedback channel information for the asymmetric S-FA, from the system channel information (AAI_SCD) of the S-FA in step <NUM>. For example, referring back to <FIG>, the MS obtains the feedback channel information <NUM> for the DL of the S-FA <NUM>, from the system channel information <NUM> of the S-FA <NUM>. The MS may obtain the information of the data channel <NUM> for transmitting the fast feedback information of the S-FA <NUM>, from the feedback polling MAP information <NUM> of the S-FA <NUM>.

Meanwhile, when the S-FA is not the asymmetric frequency band in step <NUM>, the MS obtains the feedback channel information of the S-FA, from the SFH of the S-FA in step <NUM>.

<FIG> illustrates a method of the BS for processing the feedback of the asymmetric frequency band in the wireless communication system according to another exemplary embodiment of the present invention.

In step <NUM>, the BS checks whether the serviced MSs include an MS operating in the CA mode.

When an MS manages the asymmetric S-FA, the BS transmits the feedback channel allocation information of the P-FA and the feedback channel allocation information for the S-FA using the SFH of the P-FA and the system channel information (AAI_SCD) of the S-FA in step <NUM>. For example, in <FIG>, the BS transmits the feedback channel information <NUM> for the DL of the S-FA <NUM> using the system channel information (AAI_SCD) <NUM> of the S-FA <NUM>. The BS may transmit the information of the data channel <NUM> for transmitting the fast feedback information of the S-FA <NUM> using the feedback polling MAP information <NUM> of the S-FA <NUM>.

In step <NUM>, the BS receives the feedback for the P-FA and the asymmetric S-FA over the feedback channel allocated in the P-FA according to the feedback channel allocation information sent over the SFH of the P-FA and the system channel information of the S-FA.

<FIG> is a block diagram of the MS for supporting the asymmetric frequency band in the wireless communication system according to an exemplary embodiment of the present invention.

The MS of <FIG> includes a duplexer <NUM>, a receiver <NUM>, a message processor <NUM>, a controller <NUM>, a message generator <NUM>, and a transmitter <NUM>.

The duplexer <NUM> transmits a transmit signal output from the transmitter <NUM> over an antenna, and provides a receive signal from the antenna to the receiver <NUM> according to the duplexing scheme.

The receiver <NUM> demodulates a Radio Frequency (RF) signal fed from the duplexer <NUM> to a baseband signal. The receiver <NUM> can include an RF processing block, a demodulating block, a channel decoding block, and so on. Herein, the RF processing block converts the RF signal output from the duplexer <NUM> to the baseband signal. The demodulating block includes a Fast Fourier Transform (FFT) operator for extracting data from subcarriers of the signal output from the RF processing block. The channel decoding block includes a demodulator, a deinterleaver, and a channel decoder.

Under the control of the controller <NUM>, the receiver <NUM> changes a receive frequency band. For instance, when the MS does not support the overlay mode, the receiver <NUM> changes the receive frequency band to cover the P-FA under the control of the controller <NUM>. For example, when the MS supports the overlay mode, the receiver <NUM> changes the receive frequency band to cover the P-FA and at least one S-FA under the control of the controller <NUM>.

The message processor <NUM> extracts control information from the signal output from the receiver <NUM> and provides the extracted information to the controller <NUM>. That is, the message processor <NUM> extracts the feedback channel information, the S-FA allocation information, and the S-FA indication information from the signal output from the receiver <NUM>, and provides the extracted information to the controller <NUM>. For example, when the asymmetric frequency band of <FIG> is operated, the message processor <NUM> obtains the feedback channel information <NUM> for the DL of the S-FA <NUM> from the SFH <NUM> of the S-FA <NUM>. The message processor <NUM> obtains the data channel information <NUM> for transmitting the fast feedback information of the S-FA <NUM> from the feedback polling MAP information <NUM> of the S-FA <NUM>. In another example, when the asymmetric frequency band of <FIG> is operated, the message processor <NUM> obtains the feedback channel information <NUM> for the DL of the S-FA <NUM> from the system channel information <NUM> of the S-FA <NUM>. The message processor <NUM> obtains the data channel information <NUM> for transmitting the fast feedback information of the S-FA <NUM> from the feedback polling MAP information <NUM> of the S-FA <NUM>. In the meantime, as for the symmetric frequency band, the message processor <NUM> obtains the feedback channel information <NUM> for the DL of the S-FA <NUM> from the SFH <NUM> of the S-FA <NUM>.

The controller <NUM> controls the operations and the overlay mode of the MS. The controller <NUM> controls to execute the overlay mode using the S-FA allocation information received from a serving BS, at least one S-FA activated by the S-FA indication information, and the P-FA.

According to whether the overlay mode is supported, the controller <NUM> controls the frequency bands of the receiver <NUM> and the transmitter <NUM>. For example, when the MS does not support the overlay mode, the controller <NUM> controls to define the receive frequency band of the receiver <NUM> and the transmit frequency band of the transmitter <NUM> to cover the P-FA. When the MS manages the multiple bands of <FIG>, the controller <NUM> controls to define the receive frequency band of the receiver <NUM> to cover the P-FA <NUM>. The controller <NUM> controls to define the transmit frequency band of the transmitter <NUM> to cover the P-FA <NUM> and the S-FA <NUM>.

The controller <NUM> determines whether to manage the asymmetric frequency band. For instance, the controller <NUM> checks whether the S-FA is the asymmetric frequency band using the characteristic information of the frequency band contained in at least one of the global carrier configuration (AAI_Global-Config) message, the multiple frequency band information (AAI_MC-ADV) message, and the neighbor BS information (AAI_NBR-ADV) message which are received from the serving BS. Based on the symmetric frequency band (fully configured carrier)/asymmetric frequency band (partially configured carrier) information of the frequency band characteristics, the controller <NUM> examines whether the S-FA is the asymmetric frequency band. Alternatively, the controller <NUM> may check whether the S-FA is the asymmetric frequency band, using the activation indication information for the S-FA received from the serving BS. That is, when the serving BS instructs to activate only the DL of the S-FA, the controller <NUM> recognizes that the S-FA is the asymmetric frequency band.

When managing the asymmetric frequency band, the controller <NUM> controls the message processor <NUM> to receive the feedback channel information for the asymmetric frequency band.

The message generator <NUM> generates a control message to transmit to the serving BS under the control of the controller <NUM>. For example, under the control of the controller <NUM>, the message generator <NUM> generates the control message including the multiple frequency support capability information of the MS. Herein, the multiple frequency support capability information includes the frequency bands supportable by the MS, the number of the frequency bands operable by the MS concurrently, and the guard subcarrier support. For example, the message generator <NUM> generates a feedback message of the P-FA and at least one S-FA under the control of the controller <NUM>.

The transmitter <NUM> encodes data to transmit to the serving BS and the control message output from the message generator <NUM>, converts them to an RF signal, and outputs the RF signal to the duplexer <NUM>. For example, when the asymmetric S-FA of <FIG> is managed, the transmitter <NUM> transmits the feedback information of the P-FA and the S-FA over the feedback channel <NUM> allocated in the UL of the P-FA <NUM> confirmed by the message processor <NUM>.

The transmitter <NUM> can include a channel coding block, a modulating block, and an RF processing block. Herein, the channel coding block includes a modulator, an interleaver, a channel encoder, and so on. The modulating block includes an Inverse FFT (IFFT) operator for mapping the signal output from the channel coding block to subcarriers. The RF processing block converts the baseband signal output from the modulating block to an RF signal and outputs the RF signal to the duplexer <NUM>.

The transmitter <NUM> alters the transmit frequency band under the control of the controller <NUM>.

<FIG> is a block diagram of the BS for supporting the asymmetric frequency band in the wireless communication system according to an exemplary embodiment of the present invention.

The BS of <FIG> includes a duplexer <NUM>, a receiver <NUM>, a message processor <NUM>, a controller <NUM>, a CA controller <NUM>, a message generator <NUM>, and a transmitter <NUM>.

The receiver <NUM> demodulates an RF signal fed from the duplexer <NUM> to a baseband signal. The receiver <NUM> can include an RF processing block, a demodulating block, a channel decoding block, and so on. Herein, the RF processing block converts the RF signal output from the duplexer <NUM> to the baseband signal. The demodulating block includes an FFT operator for extracting data from subcarriers of the signal output from the RF processing block. The channel decoding block includes a demodulator, a deinterleaver, and a channel decoder.

Under the control of the controller <NUM>, the receiver <NUM> changes a receive frequency band.

The message processor <NUM> extracts control information from the signal output from the receiver <NUM> and provides the extracted information to the controller <NUM>.

The controller <NUM> controls the operations of the serving BS and the transmit and receive frequencies according to whether the overlay mode is supported. More specifically, based on whether the overlay mode is supported, the controller <NUM> controls the frequency bands of the receiver <NUM> and the transmitter <NUM>. For example, when the serviced MS does not support the overlay mode, the controller <NUM> control to define the receive frequency band of the receiver <NUM> and the transmit frequency band of the transmitter <NUM> to cover the P-FA. For example, when the serviced MS manages the multiple bands of <FIG>, the controller <NUM> control to define the receive frequency band of the receiver <NUM> to cover the P-FA <NUM> and the S-FA <NUM>. The controller <NUM> also controls to define the transmit frequency band of the transmitter <NUM> to cover the P-FA <NUM>.

The CA controller <NUM> determines the S-FA of the MS based on the multiple frequency support capability information of the MS which can support the multiple bands. The CA controller <NUM> determines the region to activate in the S-FA allocated to the MS.

The message generator <NUM> generates a control message to transmit to the MS under the control of the controller <NUM>. For example, under the control of the controller <NUM>, the message generator <NUM> generates a control message including the S-FA information of the MS and a control message including the S-FA activation indication information. For example, the message generator <NUM> generates a control message including the feedback channel information of the P-FA and the S-FA. When the asymmetric S-FA of <FIG> is managed, the message generator <NUM> generates a message of the system channel information <NUM> of the S-FA <NUM> to include the feedback channel information of the S-FA. When the asymmetric S-FA of <FIG> is managed, the message generator <NUM> generates the SFH <NUM> of the S-FA <NUM> to include the feedback channel information of the S-FA.

The transmitter <NUM> encodes the data to transmit to the MS and the control message output from the message generator <NUM>, converts them to an RF signal, and outputs the RF signal to the duplexer <NUM>. The transmitter <NUM> can include a channel coding block, a modulating block, and an RF processing block. Herein, the channel coding block includes a modulator, an interleaver, a channel encoder, and so on. The modulating block includes an IFFT operator for mapping the signal output from the channel coding block to subcarriers. The RF processing block converts the baseband signal output from the modulating block to an RF signal and outputs the RF signal to the duplexer <NUM>.

Under the control of the controller <NUM>, the transmitter <NUM> alters its transmit frequency band. For example, when the serviced MS does not support the overlay mode, the transmitter <NUM> changes the transmit frequency band to cover the P-FA under the control of the controller <NUM>. When the serviced MS supports the overlay mode, the transmitter <NUM> changes the transmit frequency band to cover the P-FA and at least one S-FA under the control of the controller <NUM>.

The MS of <FIG> and the BS of <FIG> include the single transmitter and the single receiver. Note that the MS and the BS may include two or more transmitters and receivers for the P-FA and at least one S-FA.

In the exemplary embodiment of the present invention, the BS transmits the feedback channel information for the asymmetric S-FA to the MS using any one of the SFH and the system channel information (AAI_SCD) message.

Alternatively, the BS may transmit the entire feedback channel region information (number of Distributed LRUs for UL feedback channel per a UL AAI subframe) of the feedback channel information for the S-FA and the HARQ feedback transmission channel region information (number of UL ACK/NACK channels per HARQ feedback region) of the feedback channel region over the SFH, and transmit the feedback channel region start (the start LRUs index for feedback channel) through the system channel information (AAI_SCD) message.

In the exemplary embodiment of the present invention, the MS fulfills the multiple frequency band operation using one P-FA and one S-FA. Yet, the present invention is applicable to a case where the MS conducts the multiple frequency band operation using at least one S-FA. When at least one S-FA includes the asymmetric carrier aggregation, the BS transmits the feedback channel information for each asymmetric S-FA using at least one of the SFH of the asymmetric S-FA and the system channel information (AAI_SCD). Herein, the feedback channel for the asymmetric S-FA is allocated to the P-FA of the MS.

In the exemplary embodiment of the present invention, the BS transmits the feedback channel information for the asymmetric S-FA to the MS through a broadcast signal of the SFH and the system channel information (AAI_SCD).

Alternatively, the BS may transmit the feedback channel information for the S-FA to the MS through the activation indication information for the asymmetric S-FA. In this case, the feedback channel information includes the information described in Table <NUM> or Table <NUM>.

As set forth above, when the asymmetric frequency carrier aggregation is allocated to the MS in the wireless communication system, the MS transmits the channel feedback of the asymmetric S-FA using the P-FA. Therefore, the channel feedback of the asymmetric S-FA can be transmitted in the asymmetric frequency carrier aggregation.

Although the present disclosure has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims. channel feedback of the asymmetric S-FA using the P-FA. Therefore, the channel feedback of the asymmetric S-FA can be transmitted in the asymmetric frequency carrier aggregation.

Claim 1:
A method performed by a terminal in a wireless communication system, the method comprising:
receiving, from a base station, information on an index of a feedback channel resource of a primary carrier (<NUM>), wherein the information is received by using a secondary carrier (<NUM>) associated with the primary carrier; and
transmitting, to the base station, hybrid automatic repeat request-acknowledgment, HARQ-ACK, information associated with the secondary carrier through the feedback channel resource of the primary carrier,
wherein the primary carrier is used for a downlink signaling and an uplink signaling, and
wherein the secondary carrier is used for the downlink signaling.