JP5452716B2 - Method for communication using frame structure supporting H-FDD operation - Google Patents

Description

  The present invention relates to a mobile communication system, and more particularly to a method for performing communication using a frame structure that supports H-FDD operation and an apparatus using the same.

  The IEEE 802.16m (Institut of Electrical and Electronics Engineers) system is an H-FDD (Half-Frequency Division Duplex) frequency division duplex (FDD: FreqDuD Duplex). ) All methods can be supported. The IEEE 802.16m system uses Orthogonal Frequency Division Multiplexing Access (OFDMA) in the multiple connection method 7 in the downlink (DL: DownLink) and the uplink (UL: UpLink).

  Hereinafter, the frame structure of the IEEE 802.16m system will be briefly described.

  FIG. 1 is a diagram illustrating a basic frame structure in an IEEE 802.16m system.

  Referring to FIG. 1, each 20 ms superframe is divided into four 5 ms radio frames of the same size, and the superframe begins with a superframe header (SFH). In the case of having any one channel bandwidth of 5 MHz, 10 MHz, and 20 MHz, each 5 ms radio frame can be composed of 8 subframes. One subframe can be allocated for downlink or uplink transmission. The first type subframe is defined as a subframe composed of 6 OFDMA symbols, the second type subframe is defined as a subframe composed of 7 OFDMA symbols, and the third type The subframe can be defined as a subframe composed of 6 OFDMA symbols.

  The basic frame structure can be applied to all FDD and TDD systems including H-FDD terminal operations. In the TDD system, the number of switching points in each radio frame is two. A turning point can be defined by a change in directionality from the downlink to the uplink or from the uplink to the downlink.

  H-FDD terminals can be included in the FDD system, and the frame structure in terms of H-FDD terminals is similar to the TDD frame structure. However, downlink and uplink transmissions are performed in two separate frequency bands. The transmission interval between the downlink and the uplink is necessary for transmission and reception circuit switching.

  FIG. 2 is a diagram illustrating an example of an FDD frame structure for 5 MHz, 10 MHz, and 20 MHz channel bandwidths in which the CP length is 1/8 of the effective symbol length.

  Referring to FIG. 2, a base station that supports the FDD scheme can simultaneously support half-duplex and full-duplex terminals operating on the same RF carrier. A terminal that supports the FDD scheme must use either the H-FDD or the FDD scheme. All subframes are available for downlink and uplink transmission. Downlink and uplink transmissions can be distinguished in the frequency domain. One superframe is divided into four frames, and one frame can be composed of eight subframes.

  As described above, the IEEE 802.16m system must support all H-FDD (Half-Frequency Division Duplex) and F-FDD (Full-Frequency Division Duplex) methods, but maximizes system performance. However, an FDD frame structure for enhancing the speed has not been proposed yet.

  A technical problem to be achieved by the present invention is to provide a method in which a terminal performs communication using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation.

  Another technical problem to be achieved by the present invention is to provide a method in which a base station performs communication using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation.

  Still another technical problem to be achieved by the present invention is to provide a terminal apparatus using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation.

  Still another technical problem to be achieved by the present invention is to provide a base station apparatus using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation.

  The technical problem to be achieved by the present invention is not limited to the above technical problem, and other technical problems not mentioned can be obtained from the following description based on the general knowledge in the technical field to which the present invention belongs. It will be clearly understood by those who have it.

  In order to achieve the above technical problem, a method in which a terminal according to the present invention performs communication using a frame structure that supports an H-FDD (Half-Frequency Division Duplex) operation is performed from a base station to a subframe unit. Receiving resource allocation information including information on idle time allocated in step 1; and subframes allocated for idle time in a specific frame based on the received idle time allocation information Communication may be performed using the remaining one or more subframes.

  At this time, the idle time allocation information may include information indicating that the subframes allocated as idle subframes in the specific frame are the first, second and last uplink subframes. In addition, the idle time allocation information includes a downlink corresponding to a HARQ (Hybrid Automatic Repeat request) timing corresponding to each uplink subframe allocated as the idle subframe in the specific frame, and the downlink allocated as the idle subframe. Subframe information may be further included.

  At this time, 1 corresponding to the same timing as the first uplink subframe assigned as the idle subframe among the remaining downlink subframes excluding each downlink subframe assigned as the idle subframe. A superframe header or preamble may be received through the th downlink subframe.

  In order to achieve the other technical problem described above, a method in which a base station performs communication using a frame structure supporting an H-FDD (Half-Frequency Division Duplex) operation according to the present invention includes the H-FDD frame. Performing resource allocation scheduling including scheduling for allocating idle time in units of subframes to a terminal using the structure; and transmitting resource allocation information including idle time information according to the scheduling to the terminal.

  In this case, the idle time information may include information indicating that the first, second, and last uplink subframes in the specific frame in the frame structure are allocated as idle subframes. The idle time information includes HARQ (Hybrid Automatic Repeat reQuest) timing corresponding to each uplink subframe assigned as the idle subframe in the specific frame, and a downlink subframe assigned as the idle subframe. Frame information may further be included.

  Further, the method may further include transmitting a signal to the terminal through one or more remaining downlink subframes excluding each downlink subframe allocated as the idle subframe in the specific frame.

  In order to achieve the above technical problem, a terminal device that performs communication using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation relates to an idle time allocated in subframe units from a base station. A receiving module for receiving resource allocation information including information, and a signal through one or more remaining subframes excluding the subframe allocated for idle time in a specific frame based on the received idle time allocation information And a RF unit for transmitting or receiving signals through one or more remaining subframes excluding the subframes allocated for idle time under the control of the processor. be able to.

In order to achieve the technical problem described above, a base station apparatus that performs communication to support H-FDD (Half-Frequency Division Duplex) operation has idle time for a terminal using the H-FDD frame structure. A processor that performs resource allocation scheduling including scheduling allocated in units of subframes, and a transmission module that transmits resource allocation information including idle time information based on the scheduling to the terminal may be included.
This specification provides the following items, for example.
(Item 1)
In a method in which a terminal performs communication using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation in a mobile communication system,
Receiving resource allocation information including information about idle time allocated in subframe units from a base station; and
Communication using one or more remaining subframes excluding subframes allocated for idle time in a specific frame based on the received idle time allocation information. How to accomplish.
(Item 2)
Item 1 is characterized in that the idle time allocation information includes information indicating that subframes allocated as idle subframes in the specific frame are first, second and last uplink subframes. The communication performance method described.
(Item 3)
The idle time allocation information corresponds to HARQ (Hybrid Automatic Repeat reQuest) timing for an uplink subframe allocated as the idle subframe in the specific frame, and downlink subframe information allocated as an idle subframe. The communication performing method according to item 2, further comprising:
(Item 4)
The superframe header or preamble is received through the first downlink subframe corresponding to the same timing as the first uplink subframe allocated as the idle subframe. Communication execution method.
(Item 5)
Item 1 is characterized in that the specific frame has a channel bandwidth of any one of 5 MHz, 10 MHz, and 20 MHz, and a CP (Cyclic Prefix) length is 1/8 of an effective symbol length. The communication performance method described in 1.
(Item 6)
The method according to claim 1, wherein the resource allocation information is received through any one of a superframe header, a preamble, and a MAP.
(Item 7)
6. The method according to claim 5, wherein a ratio between the number of downlink subframes and the number of uplink subframes in the specific frame is 4: 4.
(Item 8)
The method according to claim 1, wherein the second uplink subframe assigned as the idle subframe is assigned for a transition gap between transmission and reception.
(Item 9)
In a method in which a base station communicates to support H-FDD (Half-Frequency Division Duplex) operation in a mobile communication system,
Performing resource allocation scheduling including scheduling to allocate idle time in units of subframes to a terminal using the H-FDD frame structure; and
A method for performing communication, comprising: transmitting resource allocation information including idle time information according to the scheduling to the terminal.
(Item 10)
The idle time information includes information indicating that the first, second, and last uplink subframes in a specific frame in the frame structure are allocated as idle subframes. Communication performance method.
(Item 11)
The idle time information corresponds to HARQ (Hybrid Automatic Repeat reQuest) timing for an uplink subframe assigned as the idle subframe in the specific frame, and includes downlink subframe information assigned as the idle subframe. The communication performance method according to item 10, further comprising:
(Item 12)
Item 10 further comprising transmitting a signal to the terminal through one or more remaining downlink subframes excluding a downlink subframe allocated as the idle subframe in the specific frame. The communication performance method described.
(Item 13)
In a terminal apparatus that performs communication using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation in a mobile communication system, resource allocation information including information on idle time allocated in subframe units from a base station Receiving module to receive;
A processor for controlling to transmit or receive a signal through one or more remaining subframes excluding the subframe allocated for idle time in a specific frame based on the received idle time allocation information; and
A terminal apparatus comprising: an RF (Radio Frequency) unit that transmits or receives a signal through one or more remaining subframes excluding a subframe allocated for idle time under the control of the processor.
(Item 14)
Item 13 is characterized in that the idle time allocation information includes information indicating that subframes allocated as idle subframes in the specific frame are first, second and last uplink subframes. The terminal device described.
(Item 15)
The idle time allocation information corresponds to HARQ (Hybrid Automatic Repeat reQuest) timing for an uplink subframe allocated as the idle subframe in the specific frame, and downlink subframe information allocated as an idle subframe. The terminal device according to Item 14, further comprising:
(Item 16)
In a base station apparatus that performs communication to support H-FDD (Half-Frequency Division Duplex) operation in a mobile communication system,
A processor for performing resource allocation scheduling including scheduling for allocating idle time in units of subframes to a terminal using the H-FDD frame structure; and
A base station apparatus comprising: a transmission module that transmits resource allocation information including idle time information by the scheduling to the terminal.
(Item 17)
Item 16. The item 16 is characterized in that the idle time information includes information indicating that the first, second and last uplink subframes in a specific frame in the frame structure are allocated as idle subframes. Base station equipment.
(Item 18)
The idle time information corresponds to HARQ (Hybrid Automatic Repeat reQuest) timing for an uplink subframe assigned as the idle subframe in the specific frame, and includes downlink subframe information assigned as the idle subframe. Item 18. The base station device according to Item 17, further comprising:
(Item 19)
The base according to item 16, further comprising a transmission module for transmitting a signal to the terminal through the remaining downlink subframes excluding the downlink subframe allocated as the idle subframe in the specific frame. Station equipment.

  According to the present invention, the operation of the H-FDD terminal can be supported without affecting the F-FDD frame structure. Therefore, the system performance in the F-FDD frame structure can be considerably improved.

  The effects obtained by the present invention are not limited to the effects mentioned above, and other effects not mentioned are clearly understood by those having ordinary knowledge in the technical field to which the present invention belongs from the following description. right.

It is the figure which showed the basic frame structure in the IEEE 802.16m system. It is the figure which showed an example of the FDD frame structure with respect to 5 MHz, 10 MHz, and 20 MHz channel bandwidth whose CP length is 1/8 of the length of an effective symbol. It is the figure which showed an example of the super-frame structure in an AAI system. It is the figure which showed an example of F-FDD frame structure in an AAI system, FDD frame structure, H-FDD frame structure, and H-FDD frame structure. It is the figure which showed the other example of the FDD frame structure in an AAI system, an FDD frame structure, an H-FDD frame structure, and an H-FDD frame structure. It is the figure which showed an example of the F-FDD frame structure in an AAI system. It is the figure which showed an example of the F-FDD frame structure and H-FDD frame structure in an AAI system. It is the figure which showed an example of the H-FDD frame structure which has 1/8 CP length in a 5 MHz, 10 MHz, and 20 MHz channel bandwidth for supporting an H-FDD terminal in an AAI system. It is the figure which showed an example of the H-FDD frame structure which has 1/16 CP length in a 5MHz, 10MHz, and 20MHz channel bandwidth for supporting an H-FDD terminal in an AAI system. FIG. 6 is a diagram illustrating an example of an H-FDD frame structure having a CP length of 1/8 in an 8.75 MHz channel bandwidth for supporting an H-FDD terminal in an AAI system. FIG. 6 is a diagram illustrating an example of an H-FDD frame structure having a CP length of 1/8 in a 7 MHz channel bandwidth for supporting an H-FDD terminal in an AAI system. It is the figure which each showed an example of the H-FDD frame structure without DL gap and the H-FDD frame structure without UL gap in an AAI system. It is the figure which each showed an example of the H-FDD frame structure without DL gap and the H-FDD frame structure without UL gap in an AAI system. It is the figure which showed an example of F-FDD frame structure in an AAI system, FDD frame structure, H-FDD frame structure, and H-FDD frame structure. It is the figure which showed an example of the H-FDD frame structure in an AAI system. 4 is a diagram showing each component of the device 50.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description disclosed below in connection with the appended drawings is intended as a description of exemplary embodiments of the invention and is not intended to represent the only embodiments in which the invention may be practiced. The following detailed description includes specific details in order to provide a thorough understanding of the present invention. However, one of ordinary skill in the art appreciates that the present invention may be practiced without such specific details. For example, the following detailed description will be specifically described assuming that the mobile communication system is a 3GPP LTE system, but the mobile communication system can be applied to any other mobile communication system except for the specific matters of 3GPP LTE. Applicable.

  In some instances, well-known structures and devices may be omitted or may be illustrated in the form of a block diagram centered on the core functions of each structure and device to avoid obscuring the concepts of the present invention. . In addition, the same constituent elements will be described using the same reference numerals throughout the present specification.

  In addition, in the following description, it is assumed that the terminal refers to a mobile or fixed user terminal device such as a UE (User Equipment), an MS (Mobile Station), an AMS (Advanced Mobile Station), or the like. Further, it is assumed that the base station refers to any node at the end of the network that communicates with a terminal such as Node B, eNode B, Base Station, AP (Access Point), and the like.

  In the mobile communication system, a terminal (User Equipment) can receive information from a base station through a downlink, and the terminal can transmit information through an uplink. Information transmitted or received by a terminal includes data and various control information, and various physical channels exist depending on the type and use of information transmitted or received by the terminal. In the present invention, an F-FDD (Full-FDD) terminal refers to a terminal using an F-FDD frame structure, and an H-FDD terminal refers to a terminal using an H-FDD frame structure. The legacy system is a system that uses a communication method before IEEE 802.16m, such as an IEEE 802.16e system.

  In the present invention, an FDD frame structure for supporting an F-FDD terminal, an H-FDD terminal, and a legacy H-FDD terminal in an AAI (Advanced Air Interface) (for example, IEEE 802.16m) system, and a signal using the same A terminal and a base station that transmit and receive data will be described. The AAI system mentioned here is only an example, and there is no restriction on the type and definition of the system. The frame structure for supporting the H-FDD terminal in the AAI system can be configured based on the FDD frame structure defined in IEEE 802.16m.

  The base station can perform resource allocation scheduling to support the operation of an H-FDD (Half-Frequency Division Duplex) terminal in the mobile communication system. For example, the base station assigns or punctures the first uplink subframe, the second uplink subframe, and the last uplink subframe as idle subframes within a specific frame, and these uplink subframes are H It can be scheduled not to be used by FDD terminals. That is, the base station can allocate idle time for downlink / uplink switching or the like on a subframe basis. The base station can transmit the resource allocation information thus scheduled to the terminal through a superframe header, a preamble, MAP information, and the like. The terminal that has received the scheduled resource allocation information (can include a subframe index, a position, and the like that can be used by the terminal) can transmit and receive signals based on the information.

  In the following, a resource allocation method and resource allocation scheduling method by a base station in a frame structure for supporting the operation of the H-FDD terminal, and the H-FDD terminal transmits and receives signals based on such resource allocation and scheduling. A method will be described.

  FIG. 3 is a diagram illustrating an example of a superframe configuration in the AAI system.

  Referring to FIG. 3, in the frame structure of the IEEE 802.16m system, four frames constitute one super frame, and data is transmitted to the terminal in units of super frames. Therefore, the H-FDD frame structure can be configured by inheriting the existing super frame structure. At this time, the terminal transmits control information transmitted from the base station in the same manner as the existing super frame structure. Important signals (e.g., superframe header (SFH), A-preamble)) must be received. The position of the important signal transmitted from each frame in one super frame is as shown in FIG.

  Regardless of the group to which the H-FDD terminal belongs, the H-FDD terminal receives a superframe header, an A-preamble (primary A-preamble), and a secondary A-preamble (secondary A- The terminal can receive each of these signals through the first subframe of each frame as shown in Fig. 3. Therefore, the H-FDD terminals belonging to each group In order to receive all these important signals transmitted from the base station, the H-FDD frame structure has the first uplink subframe of each frame in which each of these important signals is transmitted in the uplink frame region. Must be configured to allocate or puncture for idle time When puncturing one subframe in each frame in the uplink region through such a method, there is a disadvantage of wasting resources.

  As another method for transmitting an important signal such as control information to the H-FDD terminal, as shown in FIG. 3, an A-preamble transmitted from the third frame and the fourth frame in the superframe is used. Retransmission can be performed in the same manner as the A-preamble (secondary A-preamble) transmitted from the first frame. The H-FDD terminal corresponding to each group must receive the super frame header (SFH) and the A-preamble (primary A-preamble, secondary A-preamble) from the base station, so the third and fourth frames It is not always necessary to receive the same A-preamble transmitted from.

  Therefore, in order for the H-FDD terminal to receive the important signal with the H-FDD frame structure, that is, to receive the important signal transmitted from the first and second frames of the superframe, the H-FDD The frame structure may be configured to allocate or puncture an uplink subframe corresponding to a downlink subframe in which the important signal is transmitted for idle time. In this case, there is an advantage that waste of resources can be reduced as compared with a case where an H-FDD frame is configured by allocating or puncturing one subframe in all frames. However, since the H-FDD terminals belonging to group 2 in the third and fourth frames cannot receive the important signal (secondary A-preamble), the communication performance slightly decreases.

  In this case, H-FDD terminals belonging to group 1 can receive the A-preamble transmitted from the third and fourth frames and receive all important signals transmitted in the superframe. Since the H-FDD terminal belonging to the group cannot receive through the third and fourth frames, unfairness may occur in reception of important signals between groups. In order to solve this unfairness problem, in addition to allocating and puncturing the first subframe up to the second frame for idle time, the third and fourth frames By using switching between groups, such an unfair problem of receiving important signals can be solved.

  For example, when group switching is used in the fourth frame, in the first, second, and fourth frames in FIG. 3, the downlink is group 1, group 2, and the uplink is group because of the H-FDD frame structure. 2, downlink / uplink frames are allocated in the order of group 1, but in the third frame, the structure is opposite to the basic structure through switching between groups, ie, downlink is group 2, group 1, uplink is Downlink / uplink frames can be allocated in the order of group 1 and group 2.

  Therefore, when performing group switching in this way, the types and number of important signals received by H-FDD terminals belonging to Group 1 are the types of important signals received by H-FDD terminals belonging to Group 2 and the number thereof. It becomes the same as the number, and fairness can be achieved. By switching between groups, the base station transmits a group indicator to the H-FDD terminal, so that it can be known that the group to which the H-FDD terminal belongs has been changed.

  As described above, the IEEE 802.16m system must support all F-FDD terminals and H-FDD terminals. At this time, the frame structure for supporting the H-FDD terminal can be configured using an F-FDD frame structure that has been defined for the F-FDD terminal. Since the F-FDD frame structure is configured in units of subframes, the H-FDD frame structure for supporting the H-FDD terminal can also be configured in units of subframes. The H-FDD terminals can be grouped into two groups and perform the H-FDD operation like the H-FDD terminals of the existing legacy system. Unlike the F-FDD terminal, the H-FDD terminal belonging to each group needs a transition gap for downlink / uplink switching (DL / UL switching) in the H-FDD frame structure. Also, in order to align the frames so that the H-FDD frame structure is aligned with the existing FDD frame structure, it is necessary to set a transition gap in the existing FDD frame structure. It can be configured to allocate or puncture for idle time.

  FIG. 4 is a diagram illustrating an example of an F-FDD frame structure, an FDD frame structure, an H-FDD frame structure, and an H-FDD frame structure in the AAI system.

  4A shows an example of an F-FDD frame structure for F-FDD terminals, and FIG. 4B shows an F-FDD frame structure for F-FDD terminals and H-FDD terminals. FIG. 4C shows an example of an H-FDD frame structure for an H-FDD terminal.

  As shown in FIG. 4 (c), H-FDD terminals belonging to two groups in the H-FDD frame structure are located in the same position in the downlink and uplink regions for downlink / uplink switching. Existing subframes can be assigned to transition gaps or punctured for idle time. For example, for the TTG (Transmit Transition Gap) of the H-FDD terminal belonging to Group 1 and the RTG (Receive Transition Gap) belonging to Group 2 in FIG. 4 (c), the fourth in the downlink and uplink regions. Can be assigned or punctured to a gap region. At this time, the position of the subframe punctured due to the transition gap of the H-FDD terminals belonging to the two groups is merely an example, and is not limited to the fourth subframe.

  The H-FDD frame structure can be configured with a transition gap by puncturing the last uplink subframe of the uplink region for RTG of H-FDD terminals belonging to group 1. Since all H-FDD terminals belonging to each group must receive the A-Preamble and Super Frame Header (SFH) transmitted by the base station, the A-Preamble and the H-FDD frame structure through the downlink region. Uplink subframes that are in the same position as the subframe in which the superframe header is transmitted can be punctured to operate for idle time.

  Therefore, the first uplink subframe existing at the same position as the subframe in which the A-preamble or superframe header is transmitted in the uplink region is punctured, and is a frame in which the superframe header is transmitted. The FDD terminal needs a transition gap to transmit data after receiving the superframe header. In consideration of such a transition gap, the second uplink subframe can be punctured in the uplink region. As described above, in the frame in which the H-FDD terminal receives the superframe header, the first uplink subframe and the second uplink subframe in the uplink region are set to idle time or punctured. Can do. By configuring the H-FDD frame in such a manner, the frame alignment can be maintained so as to be in line with the F-FDD frame structure.

  If the RTG of the H-FDD terminal belonging to group 1 in FIG. 4C is less than or equal to the idle time, the last subframe in the uplink region is configured not to be punctured in the H-FDD frame structure. Can do. Therefore, if the transition gap for switching from uplink to downlink is sufficient for idle time, H-FDD terminals belonging to group 1 use 4 subframes for transmission of data etc. in the uplink region can do. The H-FDD terminal belonging to group 2 considers the transition gap due to superframe reception in the frame that receives the superframe header, and uses one uplink subframe less than the frame that does not receive the superframe header. Etc. can be transmitted.

  As shown in FIG. 4C, an H-FDD terminal belonging to group 2 has one uplink subframe (that is, the third uplink) in a frame in which a superframe header is transmitted from the base station. Data etc. can be transmitted using subframe (UL1), but data etc. can be transmitted using two uplink subframes UL0, UL1 in a frame in which no superframe header is transmitted.

  Optionally, in order to keep the same number of available uplink subframes for H-FDD terminals belonging to group 2 in all frames, the H-FDD frame structure is The FDD terminal can be configured not to use the second uplink subframe UL0.

  If the transition gap for downlink / uplink switching of the H-FDD terminals belonging to each group (TTG / RTG) is less than or equal to the length of one symbol, the transition gap of the two groups Therefore, some symbols of the punctured subframe can be used. That is, instead of puncturing the subframe due to the transition gap, one symbol of the subframe in which the gap is located can be assigned to the gap, and the subframe can be configured with the remaining symbols. For example, in FIG. 4C, a downlink subframe of 5 symbols may be allocated next to the third downlink subframe DL2 of group 1. It is also possible to allocate a downlink subframe of 5 symbols before the first downlink subframe DL0 of group 2.

  In order to support the H-FDD terminal, the H-FDD terminal can be supported using only one group of the H-FDD frame structures for the two groups shown in FIG. 4C. For example, in FIG. 4C, only the H-FDD frame structure of group 1 can be used. Therefore, the H-FDD frame structure for supporting the H-FDD terminal can be configured the same as the frame structure of group 1 in FIG. 4 (c). The downlink subframe DL3 and the last uplink subframe U7 may be configured to be punctured. Therefore, the ratio of the number of available downlink subframes and the number of uplink subframes of the H-FDD terminal is 3: 3.

  However, if the idle time of the FDD frame structure is large enough to include RTG, there is no need to puncture the last uplink subframe due to the transition gap. At this time, the ratio of the number of downlink subframes available to the H-FDD terminal and the number of uplink subframes is 3: 4. Therefore, the ratio of the number of available downlink subframes and the number of uplink subframes for H-FDD terminal is determined by the position of the downlink subframe punctured for TTG and the puncturing for RTG. Depending on the availability of puncturing of the last uplink subframe to be performed.

  As shown in FIG. 4C, when supporting an H-FDD terminal using subframe puncturing, the F-FDD terminal is not affected at all. Accordingly, the F-FDD terminal can transmit and receive data using all subframes in the downlink / uplink, similarly to the F-FDD frame structure shown in FIG. However, when one symbol is punctured in the downlink due to a transition gap of the H-FDD terminal, the F-FDD terminal is also configured with five symbols punctured in the downlink region. Subframes need to be used. Therefore, the base station can transmit an instruction or frame configuration information for this to all terminals.

  FIG. 5 is a diagram illustrating another example of the FDD frame structure, the FDD frame structure, the H-FDD frame structure, and the H-FDD frame structure in the AAI system.

  Referring to FIG. 5, (a) of FIG. 5 shows an example of an F-FDD frame structure for F-FDD terminals, and (b) of FIG. 5 is for F-FDD terminals and H-FDD terminals. FIG. 5C shows an example of an H-FDD frame structure for an H-FDD terminal.

  Unlike FIG. 4C, the position of the transition gap for downlink / uplink switching of the H-FDD terminals belonging to the two groups is set to be different depending on the H-FDD terminals belonging to each group. be able to. As shown in FIG. 5C, the H-FDD frame structure for each terminal belonging to group 1 is the fourth downlink subframe DL3 and uplink in the downlink region due to the transition gap. The seventh uplink subframe UL7 in the region can be configured to be punctured. Also, the H-FDD frame structure for each terminal belonging to group 2 can be configured to puncture the fifth downlink subframe DL4 due to the transition gap.

  In FIG. 5C, the H-FDD frame structure for each terminal belonging to group 2 receives the A-preamble and superframe header transmitted from the first subframe of the downlink frame. Therefore, the first subframe UL0 of the uplink frame is punctured, and in the uplink frame in which the superframe header is transmitted, the second uplink subframe UL1 is additionally punctured in consideration of the transition gap. Can be configured.

  Therefore, the H-FDD frame structure for each terminal belonging to group 1 has three subframes (first, second, third downlink) as shown in FIG. Link subframes), and the uplink can also be composed of 3 subframes (5th, 6th and 7th uplink subframes). At this time, if the RTG for group 1 is less than or equal to the idle time, the uplink does not have to be punctured, so the uplink has four subframes (5th, 6th, 7th, 8th uplink subframe).

  The frame structure for an H-FDD terminal belonging to group 2 is divided into three subframes (6th, 7th and 8th downlink subframes) in consideration of the above-described puncturing of subframes. Frame), and the uplink frame in which the superframe header is transmitted is composed of two subframes (third and fourth uplink subframes), but the A-preamble is transmitted without transmitting the superframe header. In a frame in which only the data is transmitted, it can be composed of three subframes (second, third, and fourth uplink subframes).

  The subframe index shown in (c) of FIG. 5 is configured using the subframe index of the F-FDD frame structure of (a) of FIG. 5, and the index is set for the H-FDD frame structure. Can be set differently. The above-described H-FDD frame structure is an example, and the configuration of the H-FDD frame structure for supporting each group of H-FDD terminals includes subframes that are punctured due to a transition gap. Can vary depending on location.

  Without dividing the H-FDD terminal into two groups, the H-FDD for one group among the respective H-FDD frame structures formed for the two groups shown in FIG. 5C. H-FDD terminals can be supported using only the frame structure. In addition, in order to maintain the same number of uplink subframes in all frames, the second uplink subframe UL0 may not be used in all frames of group 2.

  FIG. 6 is a diagram illustrating an example of an F-FDD frame structure in the AAI system.

  Referring to FIG. 6, (a) of FIG. 6 illustrates an example of an F-FDD frame structure for a 16m F-FDD terminal, and (b) of FIG. 6 illustrates a 16m H-FDD terminal and a legacy H-FDD. 2 shows an example of an F-FDD frame structure for supporting a terminal.

  When legacy H-FDD terminals exist, the FDD frame structure can be divided into two regions to support legacy H-FDD terminals and 16m FDD terminals. That is, the FDD frame structure can be divided into a legacy area and a 16m area. At this time, the frame can be configured such that the legacy H-FDD terminal is assigned to the legacy area and the 16m FDD terminal is assigned to the 16m area. Here, the size of the legacy zone and the 16m zone allocated for the legacy H-FDD terminal and the 16m terminal can be changed in a fixed or flexible manner, and information on each such zone is signaled to the terminal by the base station. Can be directed through.

  16m FDD and 16m H-FDD terminals use the 16m zone, and legacy H-FDD terminals use the legacy zone. At this time, the 16m F-FDD terminal can use all the resources of the 16m zone, but the 16m H-FDD terminal punctures to use the fourth subframe of the uplink as a transition gap. Cannot be used to transmit etc. Also, if the idle time is smaller than the RTG required for the 16m H-FDD terminal, the H-FDD frame structure can be configured by puncturing the last downlink subframe DL3 for the transition gap.

  FIG. 7 is a diagram illustrating an example of an F-FDD frame structure and an H-FDD frame structure in the AAI system.

  Referring to FIG. 7, (a) of FIG. 7 shows an example of an F-FDD frame structure for a 16m F-FDD terminal, and (b) of FIG. 7 is for supporting a legacy H-FDD terminal. An example of an H-FDD frame structure is shown, and FIG. 7C shows an example of an H-FDD frame structure for a 16m H-FDD terminal.

  For example, the number of downlink subframes allocated to the legacy zone for supporting legacy must be at least 3 and includes time for downlink / uplink switching within a given subframe. Can do. Therefore, the condition for the length of the downlink zone allocated to the legacy terminal can be expressed as Equation 1 below.

[Equation 1]
3 × subframe length ≦ legacy downlink zone length + TTG1
Legacy downlink zone length ≦ 4 × subframe length A downlink zone for a legacy H-FDD terminal satisfies the condition shown in Equation 1 and can be allocated in symbol units. In addition, the uplink zone can be allocated with a gap of only RTG1 from the next frame, or can be allocated within the position up to the last uplink subframe in the F-FDD frame structure.

  Due to the downlink / uplink transition gap of 16m H-FDD terminals in the 16m zone allocated for 16m F-FDD terminals and 16m H-FDD terminals, the H-FDD frame structure is 4 in the uplink zone. The third subframe uplink UL3 can be punctured and used as a gap. Also, for the TTG, the last downlink subframe can be punctured and used as a transition gap. Accordingly, the 16m H-FDD terminal operating in the 16m zone in the H-FDD frame structure is configured by puncturing the last downlink subframe DL7 and the fourth uplink subframe UL3 in order to allocate a transition gap. can do. The above-mentioned subframe index is shown with reference to the index in the F-FDD frame structure shown in FIG.

  Also, the H-FDD frame structure for supporting the H-FDD terminal appropriately adjusts the legacy downlink zone and uplink zone, and the transition gap of the legacy H-FDD terminal exists in the third subframe. It can be constituted as follows. Such an H-FDD frame structure is used after a 16m terminal uses the first uplink subframe UL0 and the second uplink subframe UL1 in the 16m zone and punctures the third uplink subframe. It can also be configured in a form in which the downlink starts.

  If the 16m zone TTG allocated for the 16m H-FDD terminal is less than or equal to the idle time, it can be configured to puncture the last downlink subframe DL7 due to the transition gap. In this case, the number of downlink subframes allocated for the 16m FDD terminal is increased by one subframe from the case of performing subframe puncturing to 4 pieces. The ratio between the number and the number of uplink subframes is 4: 3.

  In the F-FDD frame structure shown in FIG. 7 (a), since no transition gap is required for the 16m F-FDD terminal, the remaining downlink area excluding the downlink area allocated to the legacy H-FDD terminal 5th, 6th, 7th, and 8th downlink subframes, which are subframes, can be used. In the uplink region, the 16m F-FDD terminal can use the first, second, and third subframes UL0, UL1, and UL2 similarly to the 16m H-FDD terminal. However, if the legacy uplink region does not use the fourth uplink subframe UL3 region, the 16m F-FDD terminal is the first, second, third, fourth up, unlike the 16m H-FDD terminal. Data can be transmitted using link subframes UL0, UL1, UL2, and UL3. In this case, the base station can schedule or signal to the terminal.

  When supporting a 16m terminal using such an F-FDD frame structure, the H-FDD terminal punctures several subframes due to transition gaps in each region subframe used by the F-FDD terminal. However, data can be transmitted and received using the frame structure of the 16m area shown in FIG.

  As described above, an existing H-FDD frame structure can be used to support H-FDD terminals. At this time, each terminal is divided into two groups, and the downlink allocated to each group is used. Uplink frames can be constructed in the reverse order of frames. In the present invention, such a frame structure is used to align the frames so as to be in line with the previously defined FDD frame structure and to support H-FDD terminals without affecting terminals that use existing FDD frames. can do.

  Also, unlike the existing FDD frame structure, the H-FDD frame structure requires a section for switching between the downlink and the uplink assigned to each group. Therefore, it is necessary to set an idle time for downlink / uplink switching in the downlink or uplink region, and the subframe allocated for downlink / uplink switching set at this time is downlink / Can be arranged at the same position in the uplink region. Therefore, there is a gap for the switching interval between the two groups, and an H-FDD frame structure aligned with the FDD frame structure in the 5 MHz, 10 MHz, and 20 MHz channel bandwidths can be configured.

  FIG. 8 is a diagram illustrating an example of an H-FDD frame structure having a CP length of 1/8 in a 5 MHz, 10 MHz, and 20 MHz channel bandwidth for supporting an H-FDD terminal in an AAI system.

  Since the FDD frame in the 5 MHz, 10 MHz, and 20 MHz channel bandwidths is composed of a first type of subframe including 6 OFDMA (Orthogonal Frequency Multiple Access) symbols, the subframe is allocated for idle time. Is the first type of subframe, where the position of the subframe allocated or punctured for idle time may vary depending on the length of the region allocated to the two groups. Therefore, what is shown in FIG. 8 is only an example, and there is no restriction on the position of the punctured subframe.

  Since the H-FDD terminal is supported while maintaining the same frame alignment as the existing FDD frame structure, it is possible to minimize the influence on the terminal using the existing IEEE 802.16m FDD frame structure. As shown in FIG. 8, in order to support the H-FDD terminal while maintaining frame alignment with the existing FDD frame structure, switching in the downlink and uplink areas (downlink / uplink switching or uplink) is performed. One subframe can be allocated for idle time for (/ downlink switching).

  For example, one subframe existing between downlink regions assigned to two groups in an FDD frame structure composed of eight first type subframes can be used for idle time. Accordingly, there is a gap (DL gap) of only one subframe between two groups in a downlink frame. As described above, each terminal belonging to two groups in the H-FDD structure must receive an important signal (for example, superframe header, A-preamble) transmitted from each frame. As shown, the frame section in which the important signal is transmitted in the downlink region and the uplink frame section should not overlap each other. That is, an uplink subframe existing at the same position as the subframe in which the important signal is transmitted in the frame is used as an idle subframe or is punctured.

  The super frame header in the FDD frame structure of the existing IEEE 802.16m system is transmitted to the terminal through the first subframe of the first frame by the base station. Since the H-FDD frame structure uses the existing FDD frame structure, the super frame structure is transmitted in the same manner as the existing FDD frame structure. In order for all terminals to receive the super frame header in the H-FDD frame structure, as shown in FIG. 8, subframes in the frame section in which the super frame header is transmitted in the uplink region are punctured. Allocating for idle time should not overlap each other.

  In order to use such a frame configuration, a terminal can receive frame configuration information from a base station through an A-preamble, a superframe header, A-MAP, and the like. The frame configuration information includes downlink / uplink offset (DL / UL_OFFSET) information, downlink / uplink allocation information (start point information, subframe configuration information, subframe number information, subframe order information, downlink Link / uplink length information), group indicator information, TTG / RTG information, puncturing subframe information (eg, including punctured subframe index, type, position), idle time information (downlink / Uplink gap) etc.

  The H-FDD terminal that has received the frame configuration information from the base station can know information about the downlink / uplink area allocated using the frame configuration information. Here, the values of TTG and RTG transmitted through the A-preamble, superframe header, A-MAP, etc. are constant values regardless of the frame, and the frame structure in the 5 MHz, 10 MHz, and 20 MHz channel bandwidths. The value to configure can be shown as follows:

  First, the range of values of TTG1 and RTG1 which are TTG and RTG for the group 1 can be expressed as the following mathematical formula 2.

[Equation 2]
2 symbol periods <TG1 + RTG1 ≦ first type subframe period + idle time When the length of the subframe allocated for the DL gap and the switching period is the same, Can be expressed in

[Equation 3]
Two symbol intervals <TTG1 + RTG1 = DL gap + idle time Then, the range of values of TTG2 and RTG2 which are TTG and RTG for group 2 can be expressed as the following mathematical formula 4.

[Equation 4]
2 symbol intervals <TTG2 + RTG2 ≦ DL gap 2 symbol intervals <TTG2 + RTG2 ≦ subframe interval punctured in the downlink frame At this time, assuming that RTG2 = UL gap, TTG2 + RTG2 = TTG2 + UL gap Can show. Also, the value of RTG2 can be always smaller than the value of TTG1.

  With the H-FDD frame structure shown in FIG. 8, the H-FDD terminal can grasp the position of the start point of the assigned uplink frame using the DL / UL_OFFSET information received from the base station. Here, the DL / UL_OFFSET value (information) indicates an offset value corresponding to the interval from the start point of the downlink frame to the start point of the uplink frame. Therefore, by using DL / UL_OFFSET information in the frame structure, after receiving an important signal transmitted through a downlink subframe, the H-FDD terminal performs a transaction (ie, downlink / uplink switching). It is also possible to reduce the number of idle or punctured subframes allocated for use.

  Here, DL / UL_OFFSET can be transmitted for each group, or can be transmitted only to group 2, as shown in FIG. 8, to inform the start point of the uplink region. When transmitting only to group 2, the H-FDD terminal of group 1 can grasp the start point of the uplink frame using TTG1 or DL gap information. The DL / UL_OFFSET value for indicating the start point of the uplink frame may have the same value in the super frame or may have a different value for each frame. If they have the same value in the superframe, DL / UL_OFFSET can be expressed as Equation 5 below.

[Equation 5]
DL / UL_OFFSET ≧ first subframe section punctured with uplink frame + TTG2
If the DL / UL_OFFSET value varies from frame to frame, the first frame of the superframe must satisfy the condition shown in Equation 5, and in the case of the remaining frames, the range of the DL / UL_OFFSET value is set. It can be shown as the following mathematical formula 6.

[Equation 6]
2 symbol periods <DL / UL_OFFSET <1st subframe period punctured in uplink frame for DL / UL transaction When not using different DL / UL_OFFSET values in each frame, In order to receive the A-preamble and superframe header, which are important signals, in the uplink frame area, the subframe corresponding to the downlink area in which the important signal is transmitted is transmitted in the idle time. Can be assigned or punctured to form a frame. At this time, the subframe located in the first uplink subframe in each frame can always be allocated for idle time or punctured to form an H-FDD frame structure.

  FIG. 9 is a diagram illustrating an example of an H-FDD frame structure having a CP length of 1/16 in a 5 MHz, 10 MHz, and 20 MHz channel bandwidth for supporting an H-FDD terminal in an AAI system.

  An FDD frame structure having a CP length of 1/16 with 5 MHz, 10 MHz, and 20 MHz channel bandwidth can be composed of five first type subframes and three second type subframes. . Therefore, as described above, for downlink / uplink switching, the first type subframe or the second type subframe is allocated or punctured for idle time to form an H-FDD frame structure. Can be configured. Here, in order to reduce the waste of frames, it is desirable to allocate and use the first type subframe. In addition, in order for the H-FDD terminal to receive the A-preamble and superframe header, which are important signals transmitted from the downlink frame by the base station, the frame section in which the important signal is transmitted and the uplink frame section are mutually connected. It is necessary to configure the frames so as not to overlap, and as described above, it is possible to puncture the subframes in the uplink frame section that matches the subframe section including the superframe header. Also, other frames existing in the superframe can be configured by puncturing the first uplink subframe of the uplink frame in the same way. Then, without using DL / UL_OFFSET to allocate and puncture the second uplink subframe for idle time for H-FDD terminal transactions (ie, downlink / uplink switching) and It can also be used to send and receive data.

  FIG. 10 is a diagram illustrating an example of an H-FDD frame structure having a CP length of 1/8 in an 8.75 MHz channel bandwidth for supporting an H-FDD terminal in an AAI system.

  An H-FDD structure with an 8.75 MHz channel bandwidth having a CP length of 1/8 can also support an H-FDD terminal using the structure as described above. An FDD frame structure in the 8.75 MHz band having a CP length of 1/8 can be composed of a first type subframe and a second type subframe. Accordingly, subframes allocated or punctured as idle subframes for downlink / uplink switching in the H-FDD frame structure may be the first type composed of 6 symbols or 7 subframes. The second type may be configured with the symbols. In order to reduce frame waste in the H-FDD frame structure, it is desirable for efficient use of the frame that the first type of subframe is punctured or allocated for idle time. .

  As shown in FIG. 10, in the H-FDD frame structure, one subframe can be allocated for downlink / uplink switching, and the A-preamble and superframe header in which the H-FDD terminal is an important signal. In order to receive the uplink subframe, the uplink subframe matching the subframe period in which the superframe header is transmitted can be configured to be punctured. Use DL / UL_OFFSET to puncture the second uplink subframe for H-FDD terminal transaction (ie, downlink / uplink switching) or use it unallocated for idle time You can also. The types and positions of the punctured subframes illustrated in FIG. 10 are merely examples, and the present invention is not limited thereto.

  FIG. 11 is a diagram illustrating an example of an H-FDD frame structure having a 1/8 CP length in a 7 MHz channel bandwidth for supporting an H-FDD terminal in an AAI system.

  An FDD frame structure having a CP length of 1/8 with a 7 MHz channel bandwidth can be composed of a first type and a third type of subframe. Therefore, even in the frame structure of the 7 MHz channel bandwidth, when the H-FDD frame structure is configured in the same manner as the case of the 5/10/20 MHz and 8.75 MHz channel bandwidths described above, it is allocated for idle time. The type of subframe to be punctured is a first type subframe or a third type subframe. FIG. 11 illustrates an H-FDD frame structure with a 7 MHz channel bandwidth, where the positions of subframes assigned or punctured for idle time are not limited to specific positions.

  As described above, in order to support an H-FDD terminal without affecting a full-FDD terminal, an H-FDD structure can be configured using an existing FDD frame structure. The H-FDD frame structure requires a section for switching between the downlink and uplink assigned to each group, and downlink / uplink (or uplink / uplink / It is necessary to set an idle time for (downlink) switching. At this time, a gap allocated to allocate a section for downlink / uplink switching without affecting the F-FDD terminal can be configured in units of subframes. A subframe allocated for downlink / uplink switching may be configured in a downlink region or an uplink region.

  At this time, a gap for a switching period may exist between the groups in the downlink region or the uplink region depending on the position of the subframe allocated or punctured for the idle time. Accordingly, there is a gap for the switching interval between the two groups, and the H-FDD frame structure aligned with the FDD frame structure at 5/10/20 MHz is shown in FIGS. 12 and 13 below. be able to.

  FIGS. 12 and 13 are diagrams illustrating an example of an H-FDD frame structure without a DL gap and an H-FDD frame structure without a UL gap, respectively, in an AAI system.

  Since the FDD frame for the 5 MHz, 10 MHz, and 20 MHz channel bandwidths is composed of the first type subframe, the subframe allocated for the idle time is the first type subframe. At this time, the position of the subframe allocated or punctured for the idle time may vary depending on the length of the area allocated to the two groups. Accordingly, the positions of the subframes that are punctured or allocated for idle time in FIGS. 12 and 13 are merely examples, and the present invention is not limited thereto.

  As shown in FIG. 12, in order to set a gap for downlink / uplink switching of the H-FDD terminal, a switching period can be allocated in the uplink region. Since the idle time for switching is set in the uplink region, there is no DL gap between the two groups in the downlink region. Similar to the FDD frame structure, the H-FDD frame structure in the 5 MHz, 10 MHz, and 20 MHz channel bandwidths is composed of the first type of subframe and must maintain the frame alignment. Therefore, the number of subframes allocated for switching between the downlink and the uplink in the uplink region needs to be at least two in consideration of reception of important signals of the H-FDD terminal.

  In contrast to the H-FDD frame structure shown in FIG. 12, the H-FDD frame structure shown in FIG. 13 is a sub-domain for idle time in the downlink region for a section for downlink / uplink switching. Allocate a frame. In this case, there is no gap between the two groups in the uplink region. Also, for downlink / uplink switching, one subframe may be allocated for the idle time or punctured in each of the downlink region and the uplink region.

  The H-FDD terminal and / or the F-FDD terminal receives information on subframes allocated for switching between the downlink and the uplink from the base station through a superframe header or additional broadcasting information (ABI). can do. At this time, subframe configuration information, which is information related to subframes assigned for downlink / uplink switching, includes subframe number information, subframe position (or index) information, and downlink / uplink. Including subframe region information (downlink or uplink) allocated for switching. In the case of an F-FDD terminal, since the H-FDD frame structure is not affected by the existing FDD frame structure, signals and data are also transmitted using subframes allocated or punctured for idle time. Can do.

  As shown in FIGS. 12 and 13, the 16m H-FDD terminals belonging to each group must receive important signals such as a superframe header and an A-preamble transmitted by the base station. Therefore, in order for the H-FDD terminal to receive such a signal, the signal is not transmitted in the uplink region overlapping with the downlink section (the first subframe of the frame) in which the important signal is transmitted. That is, the overlapping section can be set as an idle time. Therefore, in order for the H-FDD terminal to receive such an important signal, the first subframe of the frame can be set as an idle time in the H-FDD frame structure. However, the A-preamble is transmitted by the base station together with the superframe header from only the first subframe of the first frame in the superframe in the 16m FDD frame structure, and the first subframe of the remaining frames in the superframe is transmitted. Only transmits the A-preamble.

  However, it is not efficient in the frame structure that the H-FDD terminal sets the first subframe of the frame as an idle time in order to receive the important signal. Therefore, in order to reduce the idle time of such a subframe, it is possible to transmit the DU_OFFSET value to the H-FDD terminal and use the uplink without puncturing the first subframe. Here, the DU_OFFSET value indicates a timing offset value from the start point of the downlink frame to the start point of the uplink frame. At this time, the DU_OFFSET value may have a positive value or a negative value depending on the start position of the uplink frame from the start point of the downlink frame.

  For example, if the start of the uplink frame is ahead of the start of the downlink frame, the DU_OFFSET value has a negative value. In the remaining frames excluding the first frame in the superframe, only the A-preamble is transmitted without the superframe header, so that the subframe is superimposed on the first subframe of the downlink superframe in the uplink region. In the remaining frames excluding, idle time for receiving the preamble may be set. Therefore, when the DU_OFFSET value is set in consideration of such idle time, for example, as shown in FIG. 12 and FIG. 13, the base station sets the DU_OFFSET value to TTG2 + 1 symbol intervals, and adds a superframe header or additional value. It can be transmitted to the H-FDD terminal through broadcast information (ABI). The H-FDD terminal that receives such a signal from the base station starts an uplink frame with a time difference from the downlink frame by DU_OFFSET. Therefore, by adjusting the DU_OFFSET value, it is not necessary to set or puncture the first subframe for idle time in the remaining frames except the first frame. Therefore, there is an advantage that the uplink region can be used more efficiently. In addition, since there is no influence on the FDD frame structure composed of subframes composed of six symbols, there is no influence on existing F-FDD terminals. At this time, the DU_OFFSET value can be variously defined as the following mathematical formula 7 and mathematical formula 8.

[Equation 7]
DU_OFFSET ≧ TTG2 + PS_1Symbol
DU_OFFSET <Symbols_subframe × PS_1Symbol-RTG2
DU_OFFSET <Symbols_subframe × PS_1Symbol + PS_Idle-RTG1)
Here, PS_1 Symbol is the number of PS for each symbol, and Symbols_subframe is the number of symbols for each subframe.

  When the above definition is expressed at the symbol level, it can be expressed as the following mathematical formula 8.

[Equation 8]
DU_OFFSET ≧ ceil (TTG2 + PS_1Symbol, PS_1Symbol),
DU_OFFSET ≦ ceil (Symbols_subframe × PS_1Symbol-RTG2, PS_1Symbol),
DU_OFFSET ≦ ceil (Symbols_subframe × PS_1Symbol + PS_Idle-RTG1, PS_1Symbol)
Here, PS_1 Symbol is the number of PS for each symbol, Symbols_subframe is the number of symbols for each subframe, and ceil is a function symbol for obtaining a large constant closest to the decimal point.

  In addition, a timing parameter necessary for switching between groups in the H-FDD frame structure can be defined as the following mathematical formula 9.

[Equation 9]
RTG1 = Symbols_subframe × PS_1Symbol + Idle−TTG1
RTG2 = Symbols_subframe × PS_1Symbol-TTG2
TTG1 + RTG1 = Symbols_subframe × PS_1Symbol + PS_Idle
TTG2 + RTG2 = (Symbols_subframe−1) × PS_1Symbol
Here, when TTG1 ≧ α, α is the minimum TTG1 required in the frame, and TTG1 may not change for each frame, and can be transmitted as a super frame header message in PS units.

And TTG2 ≧ β
β is the minimum TTG2 required in a frame, and TTG2 may not be changed for each frame, and can be transmitted as a superframe header message in PS units.

  PS_1Symbol is the number of PSs per symbol, Symbols_subframe is the number of symbols per subframe, the number of symbols in the first type subframe is 6, the number of symbols in the second type subframe is 7, The number of symbols in the third type subframe is 5, and the number of symbols in the fourth type subframe is 9. PS_Idle = number of PSs by frame−Symbols_frame × PS_1Symbol.

  Also, the H-FDD terminal can grasp the starting point of the uplink region using the DU_OFFSET value received from the base station through the super frame header or the additional broadcast information. Also, other H-FDD frame parameters received from the base station through the superframe header or ABI (for example, the number of subframes by group, configuration information, DL gap / UL gap, gap size, gap position, puncture) Each terminal belonging to each group uses the position (or index) of the charled subframe, the number of punctured subframes, TTG1, TTG2, RTG1, RTG2, etc. Can know.

  If the transition gap is required in the H-FDD frame structure, the subframe can be punctured. Such a punctured subframe is not allocated to the H-FDD terminal. Since the H-FDD terminal must receive the superframe header and the preamble, the uplink subframe corresponding to the downlink subframe in which the superframe header and the preamble exist (for example, the first uplink subframe) is punctured. You can charing.

  In a frame with a superframe header, the uplink subframe (eg, the second uplink subframe) next to the downlink subframe with the superframe header and preamble may be punctured due to a transition gap. Yes (may not be punctured in frames that do not have a superframe header). In order to guarantee a transition gap (in symbol units) in a subframe in which a superframe header exists, for example, when seven OFDMA symbols are configured in a second type subframe, Since the corresponding next uplink subframe (for example, the second uplink subframe) is not punctured, it can be allocated for data transmission / reception. And in case of the last uplink subframe, it can be punctured due to the transition gap.

  For the reasons described above, there may be subframes (subframes that are not allocated to H-FDD terminals) punctured in the uplink and / or downlink for H-FDD operation. The base station can schedule for the H-FDD terminal with the remaining resources except for the punctured uplink subframe. The H-FDD terminal can operate based on the same HARQ (Hybrid Automatic Repeat request) timing as the F-FDD frame structure except for the punctured subframe. That is, the base station determines the downlink subframe corresponding to the uplink subframe based on the HARQ timing of the punctured uplink subframe and F-FDD (the downlink determined by the system in consideration of the processing time and the like). Scheduling for the H-FDD terminal can be performed with the remaining resources excluding (subframe). If a downlink subframe needs to be punctured, the corresponding uplink subframe can also be punctured.

  At this time, when the base station schedules the H-FDD terminal, considering the TTG and RTG, a sub-frame of any downlink subframe and uplink subframe to which one H-FDD terminal has been allocated in the frame. The number of frames needs to have a difference of at least 2 or more. That is, when transitioning from the downlink to the uplink or from the uplink to the downlink, one or more subframes can be used as the transition gap (there is an exception when the idle time can be used as the RTG). ). By minimizing uplink punctured subframes, scheduling flexibility for H-FDD terminals can be maximized.

  FIG. 14 is a diagram illustrating an example of an F-FDD frame structure, an FDD frame structure, an H-FDD frame structure, and an H-FDD frame structure in the AAI system.

  14A shows an example of an F-FDD frame structure for F-FDD terminals, and FIG. 14B shows an example of an F-FDD frame structure for F-FDD terminals and base stations. FIG. 14 (c) shows an example of an H-FDD frame structure for an H-FDD terminal.

  Based on HARQ (Hybrid Automatic Repeat reQuest) timing of F-FDD, the first uplink subframe UL0 and the second uplink subframe UL1 are allocated for superframe header, preamble decoding, and transition gap, respectively. Can do. That is, the first uplink subframe UL0 and the second uplink subframe UL1 are not allocated to the H-FDD terminal. Therefore, the fifth downlink subframe DL4 and the sixth downlink subframe DL5 corresponding to the first uplink subframe UL0 and the second uplink subframe UL1 are also not allocated to the H-FDD terminal. However, if there is no superframe header, the second uplink subframe UL1 can be allocated to the H-FDD terminal and used. The eighth uplink subframe UL7 can be set to idle time to switch from the uplink to the downlink. However, if the idle time is sufficient for the RTG, the eighth uplink subframe UL7 and the fourth downlink subframe DL3 corresponding thereto can be allocated to the H-FDD terminal. By minimizing uplink punctured subframes in this way, scheduling flexibility for H-FDD terminals can be maximized.

  FIG. 15 is a diagram illustrating an example of an H-FDD frame structure in the AAI system.

  When the embodiment related to FIG. 14 is interpreted differently, the H-FDD terminal of group 1 consisting of (DL0, DL1, DL2, (DL3), UL4, UL5, UL6, (UL7)) and (DL0, UL2, It can be considered that resources are flexibly allocated to the H-FDD terminals by scheduling without distinguishing the groups for the H-FDD terminals of group 2 consisting of UL3, UL4, DL6, DL7).

  That is, the first downlink subframe DL0 and the corresponding fifth uplink subframe UL4 can always be used in consideration of HARQ timing, and are necessary for the transition gap of the H-FDD terminal. Two groups may exist based on puncturing of subframes, and the base station considers the transition gap of the H-FDD terminal based on the total resources existing in the two groups, and each H -Scheduling (or additional signaling (MAP, broadcast or unicast via MAP, message control channel)) to FDD terminals as appropriate. Here, the subframe index is shown using the subframe index of the F-FDD frame structure shown in FIG. 14A, and the index is set differently for the H-FDD frame structure. can do.

  As described above, when all of the H-FDD (Half-Frequency Division Duplex) method and the F-FDD (Full-Frequency Division Duplex) method are considered, it is necessary to maximize the system performance. At this time, the system performance can be limited mainly by the F-FDD performance. In order not to affect the F-FDD operation from the viewpoint of performance and signaling, it is not desirable that the F-FDD terminal coexisting with the H-FDD terminal operates at a lower performance. Also, when the F-FDD terminal coexists with the H-FDD terminal, it is not desirable to change the F-FDD frame structure because additional signaling is necessary. Further, in order not to affect the uplink control channel, it is necessary to design the uplink so that there is no third type subframe composed of 5 OFDMA symbols.

  In order not to affect the F-FDD operation, some subframes can be punctured for the H-FDD operation within the F-FDD frame structure used by the H-FDD terminal. Resources that are not punctured from the base station can be allocated to the H-FDD terminal by scheduling.

  FIG. 16 is a diagram showing each component of the device 50. This apparatus 50 may be a terminal or a base station. The apparatus 50 includes a processor 51, a memory 52, a radio frequency unit (RF unit) 53, a display unit 54, and a user interface unit 55. Each layer of the radio interface protocol is implemented in the processor 51. The processor 51 provides a control plane and a user plane. The functions of each layer can be implemented in the processor 51. The processor 51 may include a contention resolution timer. The memory 52 is connected to the processor 51 and stores an operating system, applications, and general files. When the device 50 is a UE, the display unit 54 displays various information and can use well-known elements such as an LCD (Liquid Crystal Display) and an OLED (Organic Light Emitting Diode). The user interface unit 55 can be configured by a combination of well-known user interfaces such as a keypad and a touch screen. The RF unit 53 can be connected to the processor 51 to transmit and receive wireless signals. The RF unit 53 can include a transmission module (not shown) and a receiving module (not shown).

  Each layer of the radio interface protocol between the terminal and the network is based on the first three layers L1, the second layer L2, and the lower three layers of the OSI (open system interconnection) model well known in the communication system. It can be classified into the third layer L3. The physical layer or the PHY layer belongs to the first layer and provides an information transmission service through a physical channel. The radio resource control (RRC) layer belongs to the third layer and provides control radio resources between the UE and the network. The UE and the network exchange RRC messages through the RRC layer.

  Each embodiment described above is obtained by combining each component and feature of the present invention in a predetermined form. Each component or feature must be considered optional unless explicitly stated otherwise. Each component or feature can be implemented in a form that is not combined with other components or features. In addition, it is possible to configure an embodiment of the present invention by combining some components and / or features. The order of each operation described in each embodiment of the present invention can be changed. Some configurations and features of one embodiment may be included in other embodiments or replaced with corresponding configurations or features of other embodiments. It is obvious that claims which are not explicitly cited in the claims can be combined to constitute an embodiment, or new claims can be included by amendment after application.

  Embodiments according to the present invention can be implemented by various means such as hardware, firmware, software, or a combination thereof. When implemented in hardware, one embodiment of the present invention includes one or more ASICs (Application Specific Integrated Circuits), DSPs (Digital Signal Processors), DSPDs (Digital Signal Processing D, Digital Signal Processing D). , FPGAs (Field Programmable Gate Arrays), processors, controllers, microcontrollers, microprocessors, and the like.

  In the case of implementation by firmware or software, an embodiment of the present invention can be implemented in the form of a module, procedure, function, or the like that performs the functions or operations described above. The software code can be stored in a memory unit and driven by a processor. The memory unit is located inside or outside the processor, and can exchange data with the processor by various means already known.

  It will be apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential characteristics thereof. Therefore, the foregoing detailed description should not be construed as limiting in any respect, but should be considered exemplary. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the invention are included in the scope of the invention.

  A method of performing communication by MS (Mobile Station) using a frame structure that supports H-FDD (Half-Frequency Division Duplex) operation is applicable to mobile communication systems such as 3GPP LTE, LTE-A, and IEEE 802.16m systems. Is done.

Claims (14)

A method of performing the H-FDD operation in an H-FDD mobile station (H-FDD MS) using an FDD frame structure supporting half frequency division duplex (H-FDD) operation in a mobile communication system, ,
Transmitting a signal through at least one uplink subframe except for the first uplink subframe, the second uplink subframe and the last uplink subframe of the FDD frame;
The first uplink subframe, the second uplink subframe, and the last uplink subframe of the FDD frame are configured as idle subframes for the H-FDD MS,
The first uplink subframe is located at the start of the FDD frame, and the second uplink subframe follows immediately after the first uplink subframe in the FDD frame;
The method of claim 1, wherein the first uplink subframe is aligned with the first downlink subframe in the time domain of the FDD frame. The downlink subframe corresponding to the HARQ (Hybrid Automatic Repeat reQuest) timing of the first uplink subframe, the second uplink subframe, and the last uplink subframe is the same as the H-FDD MS. The method of claim 1, further configured as an idle subframe. The method of claim 1, further comprising receiving a superframe header (SFH) or preamble from the BS through the first downlink subframe. The channel bandwidth of the uplink frame or the downlink frame is one of 5 MHz, 10 MHz, and 20 MHz, and the length of the cyclic prefix (CP) is 1/8 of the length of the effective symbol. The method of claim 1. The method according to claim 4, wherein a ratio of the number of downlink subframes to the number of uplink subframes in the specific FDD frame is 4: 4. The method of claim 1, wherein the second uplink subframe and the last uplink subframe in the idle subframe are for a transition gap between transmission and reception. A method of performing the H-FDD operation in a base station (BS) using a frequency division duplex (FDD) frame structure that supports half frequency division duplex (H-FDD) operation in a mobile communication system, the method comprising:
Scheduling at least one subframe except for the first uplink subframe, the second uplink subframe and the last uplink subframe of the FDD frame,
The first uplink subframe, the second uplink subframe, and the last uplink subframe of the FDD frame are configured as idle subframes for H-FDD MS,
The first uplink subframe is located at the start of the FDD frame, and the second uplink subframe follows immediately after the first uplink subframe in the FDD frame;
The method of claim 1, wherein the first uplink subframe is aligned with the first downlink subframe in the time domain of the FDD frame. The downlink subframe corresponding to the HARQ (Hybrid Automatic Repeat reQuest) timing of the first uplink subframe, the second uplink subframe, and the last uplink subframe is the same as the H-FDD MS. 8. The method of claim 7, further configured as an idle subframe. The method of claim 8, further comprising transmitting data to the H-FDD MS through one or more other downlink subframes excluding the downlink subframe. 9. The method of claim 8, further comprising transmitting a super frame header (SFH) or preamble to the H-FDD MS through the first downlink subframe. An H-FDD mobile station (MS) that performs the H-FDD operation using a frequency division duplex (FDD) frame structure that supports half frequency division duplex (H-FDD) operation in a mobile communication system, FDD MS
A transmitter,
With processor
Including
The processor, wherein the transmitter transmits a signal through at least one uplink subframe except for a first uplink subframe, a second uplink subframe and a last uplink subframe of an FDD frame; Is configured to control
The first uplink subframe, the second uplink subframe, and the last uplink subframe of the FDD frame are configured as idle subframes for the H-FDD MS,
The first uplink subframe is located at the start of the FDD frame, and the second uplink subframe follows immediately after the first uplink subframe in the FDD frame;
The H-FDD MS, wherein the first uplink subframe is aligned with the first downlink subframe in the time domain of the FDD frame. The downlink subframe corresponding to the HARQ (Hybrid Automatic Repeat reQuest) timing of the first uplink subframe, the second uplink subframe, and the last uplink subframe is the same as the H-FDD MS. The H-FDD MS according to claim 11, further configured as an idle subframe. A base station (BS) for transmitting resource allocation information using a frequency division duplex (FDD) frame structure supporting half frequency division duplex (H-FDD) operation in a mobile communication system, wherein the BS is
A processor configured to perform scheduling of at least one subframe except for the first uplink subframe, the second uplink subframe, and the last uplink subframe of the FDD frame;
The first uplink subframe, the second uplink subframe, and the last uplink subframe of the FDD frame are configured as idle subframes for H-FDD MS,
The first uplink subframe is located at the start of the FDD frame, and the second uplink subframe follows immediately after the first uplink subframe in the FDD frame;
The first uplink subframe is aligned with the first downlink subframe in the time domain of the FDD frame. The downlink subframe corresponding to the HARQ (Hybrid Automatic Repeat reQuest) timing of the first uplink subframe, the second uplink subframe, and the last uplink subframe is the same as the H-FDD MS. The BS according to claim 13, further configured as an idle subframe.

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