RU2507685C2 - Method of updating system information of base station in relay station of broadband wireless access system - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: invention particularly discloses a method of updating system information of an advanced base station (ABS) in an advanced relay station (ARS) of a broadband wireless access system which involves receiving a first message which includes altered information about base station system information from a base station; sending a second message to acknowledge reception of the first message to the base station and applying the altered information.

EFFECT: efficient updating of base station information in a relay station.

15 cl, 8 dwg

Description

Technical field

The present invention relates to a broadband wireless access system and, more specifically, to a method for efficiently updating base station information in a relay station and to an apparatus for performing this method.

State of the art

A relay station (RS) is expected to be widely used in the next generation wireless communication system. A relay station (RS) will be briefly described below.

The standardization project under the new name of multi-hop relay is currently being developed under the IEEE (Institute of Electrical and Electronics Engineers) 802.16, 2006, since the publication of the IEEE 802.16-2004 standard based on fixed subscriber mobile stations, and the IEEE 802.16е-2005 standard for providing mobility of subscriber mobile stations.

This standardization project, led by Task Force j (IEEE 802.16) under IEEE 802.16, began to discuss usage patterns, related technologies and specifications at the second meeting in July 2006 after the first formal meeting in May 2006. the IEEE 802.16 j group will be abbreviated as “802.16 j”.

The concept of the relay station, which will be described below, can remain essentially the same as the relay station adopted by the 3GPP LTE-A system. In addition, a relay station that performs the same or similar functions in various different wireless access systems can be similarly used with respect to the relay station described in the present invention.

The project authorization request (PAR) of 802.16j is aimed at expanding the coverage area and increasing productivity as standardization tasks to be performed.

Relay stations can be divided into two types of relay stations, namely “transparent” relay stations and “opaque” relay stations. In the case of a “transparent” relay station, all operations and functions are performed inside the relay station. On the other hand, in relation to an “opaque” relay station, all operations and functions are performed between the macro base station and the mobile station. In this case, the used relay station serves to perform its relay functions through the macro base station between the macro base station and the mobile station.

A mobile station considers a “transparent” relay station and an “opaque” relay station as one macro base station without identifying a “transparent” relay station and an “opaque” relay station. In this case, although there is no change in operations, the mobile station can classify the relay station according to a macro base station.

A network that includes a relay station includes a base station (BS), a relay station (RS), and a mobile station (MS). A mobile station can receive a radio signal even outside the cellular zone of a base station through a relay station. In addition, a high-quality propagation path having a high level adaptive modulation and coding (AMC) circuitry can be routed through the relay station to the mobile station within the cellular communication area of the base station. Accordingly, the user can gain in improving system performance using the same radio resources.

The standard to be developed by the 802.16j group has defined requirements. For example, a mobile station, implemented on the basis of existing standards 802.16-2004 and 802.16e-2005, should provide communication with a relay station without any additional function. Accordingly, the range of application of the relay station may be limited in relation to the existing system so as to add some function for controlling the relay station to the relay station and the existing base station. The standard for the relay station is expected to be a key factor in standardization.

A relay station can be considered as a subscriber mobile station that performs operations of the physical layer and the network access control (MAC) layer. In addition, the relay station is controlled mainly by the base station, but may, if necessary, have a predetermined control function. As usage patterns are being discussed, various types of relay stations are being considered in addition to fixed relay stations. Examples of relay stations include a mobile relay station for temporarily providing services in a particular area and a relay station that can be installed in automobiles or underground tunnels.

The main technical issues that will be discussed below can be described as follows:

1) the identification procedure of the relay station existing in the base station, and the acquisition and maintenance of information on the network topology with the relay station;

2) determining the physical structure of frame transport between the mobile station and the relay station, which is backward compatible with the existing IEEE 802.16 station;

3) a signaling procedure for mobility between relay stations or between a relay station and a base station; and

4) the procedure for connecting the network of the relay station to the base station and the procedure for connecting the mobile station through the relay station.

The relay station exchanges data with both the mobile station and the base station. However, since the relay station is synchronized with the base station, the relay station and the base station broadcast system information at the same time. Therefore, the relay station broadcasts its system information in accordance with the transmission mode when the base station transmits system information. In this case, a problem arises in that the relay station cannot receive the system information of the base station. In addition, as described above, the relay station has an interval for receiving data from the base station. In this regard, a method for reporting an interval of a mobile station and a slave relay station is required.

Description of the invention

Technical problem

The present invention is directed to a method for effectively updating system information of a base station in a relay station and an apparatus for performing this method, which essentially eliminates one or more problems associated with the limitations and disadvantages of the prior art.

An object of the present invention is to provide a method for efficiently acquiring altered system information of a base station in a relay station and an apparatus for this.

Another objective of the present invention is to provide a method for efficiently transmitting system information additionally required for a relay station to a mobile station and a slave relay station, and devices for this.

Additional advantages, objects, and features of the invention will be set forth in part in the following description and in part will become apparent to those skilled in the art upon study of the following, or may be understood from the practical application of the invention. The objectives and other advantages of the invention can be realized and achieved by the structure, in particular indicated in the written description and claims, as well as shown in the accompanying drawings.

Solution

To achieve these goals and other advantages in accordance with the purpose of the invention, implemented and described in detail here, a method for updating system information of an advanced base station (ABS) in an advanced relay station (ARS) of a broadband wireless access system comprises receiving a first message that includes the changed information of the system information of the base station from the base station; transmitting a second message to confirm receipt of the first message to the base station; and implementing the application of the amended information.

In this case, the system information includes a first subpacket, a second subpacket and a third subpacket, and the changed information includes a change count field indicating the number of changes in system information, a display bitmap field indicating whether each of the subpackets has been updated as 1 bit, and update information of a subpacket corresponding to a bit set to “1” in the display bitmap field.

In addition, the update information of each subpacket includes a super-frame number action field indicating when update information of the corresponding sub-packet is applied in the super-frame block, and the step of applying the changed information is performed on the sub-packets at a point in time indicated by the super-frame number action field.

In another aspect of the present invention, a method for reporting a change in system information from an advanced base station (ABS) to an advanced relay station (ARS) in a broadband wireless access system comprises transmitting a first message that includes changed information of system information of a base station to a relay station; and receiving a second message from the relay station to confirm receipt of the first message.

In this case, the system information includes a first subpacket, a second subpacket and a third subpacket, the changed information includes a change count field indicating the number of changes in system information, a display bitmap field indicating whether each of the subpackets has been updated as 1 bit, and update information of a subpacket corresponding to a bit set to “1” in the display bitmap field, and update information of each subpacket includes a super-frame action field indicating the time when rimenyaetsya update information of the corresponding sub-packet in the super-block.

In addition, the method further comprises retransmitting the first message to the relay station if the second message is not received from the relay station.

In another aspect of the present invention, an Advanced Relay Station (ARS) operating in a broadband wireless access system comprises: a processor; and a radio frequency (RF) module transmitting and receiving a radio signal to and from the environment under the control of the processor; moreover, the processor receives the modified system information of the advanced base station (ABS) through the first message received from the base station, transmits a second message to confirm receipt of the first message to the base station, controlling the RF module, and controls the RF module to implement the changed information.

In this case, the system information includes the first subpacket, the second subpacket and the third subpacket, and the changed information includes a change count field indicating the number of changes in the system information, a display bitmap field indicating whether each subpacket has been updated as 1 bit, and update information of a subpacket corresponding to a bit set to “1” in the display bitmap.

In addition, the update information of each subpacket includes a superframe number action field indicating the time when the update information of the corresponding subpacket is applied in the superframe unit, and the step of applying the changed information is performed on the subpackets at the time indicated by the superframe number action field.

In the above aspects, the first message is preferably transmitted from the base station in accordance with an event-triggered mode whenever system information is changed.

Preferably, in the above aspects, the first message is a message with the necessary system information for the relay station (RS-ESI), and the second message is an ACK (AAI_MSG-ACE) message.

Beneficial effects of the invention

According to embodiments of the present invention, the following advantages may be provided.

First of all, the relay station will be able to effectively receive the changed system information of the base station through a message with the necessary system information and apply the received system information at the time when the base station wants to do this.

In addition, system information additionally required for the relay station, such as zone information and hop information, can be efficiently transmitted to the mobile station.

It should be understood that both the foregoing general description and the following detailed description of the present invention are illustrative and explanatory and are intended to provide a deeper explanation of the present invention.

Brief Description of the Drawings

The accompanying drawings, which are included here to provide a further understanding of the invention and are an integral part of the present application for the invention, illustrate the embodiment (s) of the invention and together with the description serve to explain the principle of the invention. In these drawings:

FIG. 1 is a block diagram illustrating the frame structures of a relay station and a base station corresponding to a frequency division duplex (FDD) mode of a conventional IEEE 802.16m system;

FIG. 2 is a block diagram illustrating the frame structures of a relay station and a base station corresponding to a time division duplex (TDD) mode of a conventional IEEE 802.16m system; FIG.

FIG. 3 is a diagram illustrating an example of reporting zone information of a relay station via a zone map according to one embodiment of the invention; FIG.

FIG. 4 is a diagram illustrating another example of reporting zone information of a relay station via a zone map according to one embodiment of the invention; FIG.

FIG. 5 is a block diagram illustrating an example of constructing a network comprising a base station and a slave relay station.

FIG.6 is a flowchart illustrating an example of a procedure for updating system information of a base station in a relay station according to another embodiment of the present invention;

FIG. 7 is a flowchart illustrating an example of a method for generating a relay station identifier and a multicast identifier according to another embodiment of the present invention; FIG. and

FIG. 8 is a block diagram illustrating an example of a transmitter and a receiver according to another embodiment of the present invention.

The method of carrying out the invention

Detailed references will now be made to preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Where possible, the same reference numbers will be used throughout the drawings with reference to the same or similar parts.

The present invention relates to a wireless access system. The following embodiments of the present invention disclose methods for efficiently transmitting / updating system information in a relay station.

The embodiments described below are provided by a combination of structural elements and features of the present invention in a predetermined manner. Each of the structural elements or features should be considered selectively in the absence of other indications. Each of the structural elements or features may be performed without combination with other structural elements or features. In addition, some structural elements and / or features may be combined with each other to form embodiments of the present invention.

The sequence of operations described in the embodiments of the present invention may be changed. Some structural elements or features of one embodiment may be included in another embodiment or may be replaced by corresponding structural elements or features of another embodiment.

Embodiments of the present invention are described based on the transmission and reception of data between a base station and a mobile station. In this case, the base station refers to the end node of the network, which provides direct communication with the mobile station. A particular operation, which is described as being performed by a base station, may be performed by a node of a higher level than the base station, as the case may be.

In other words, it should be obvious that various operations performed to provide communication with a mobile station in a network that includes multiple network nodes along with a base station can be performed by a base station or network nodes other than the base station. A base station (BS) can be defined in other terms, such as a fixed station, Node B, eNode B (eNB), access point (AP), and advanced base station (ABS).

Other terms such as user equipment (UE), mobile subscriber station (MSS), advanced mobile station (AMS), and mobile terminal (MT) may also be used to define a mobile station.

Embodiments of the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. If an embodiment according to the present invention is implemented in hardware, such an embodiment may be implemented by one or more specialized integrated circuits (ASIC), a digital signal processor (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD), programmable by users gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, etc.

If an embodiment according to the present invention is implemented by firmware or software, then the method corresponding to the embodiments of the present invention can be implemented by some type of module, procedure or function that performs the functions or operations described above. For example, programmable code may be stored in a memory device and then executed by a processor. The storage device may be located inside or outside the processor to transmit and receive data to and from the processor through various well-known means.

Embodiments of the present invention may be supported by standard documents described in at least one of the wireless access systems, that is, the IEEE 802 system, the 3GPP system, the 3GPP LTE system, and the 3GPP2 system. Namely, among the embodiments of the present invention, steps or parts that are not described in detail to explain the technical features of the present invention can be supported by the aforementioned standard documents. In addition, all terminology used here can be described in the aforementioned standard documents. In particular, embodiments of the present invention may be supported by one or more standard documents of the IEEE 802.16 system, i.e., P802.16e-2004, P802.16e-2005, P802.16Rev.2 and IEEE P802.16m.

The specific terminology used below in the embodiments of the present invention serves to assist in understanding the present invention, and various changes can be made with reference to this specific terminology, provided that they do not deviate from the technical nature of the present invention.

The following assumptions will be described in relation to a broadband wireless access system including a relay station according to embodiments of the present invention:

1) the relay station is synchronized with the macro base station;

2) although the mobile station is served from a relay station, it is synchronized with the macro base station to which the corresponding relay station belongs;

3) in the case of a “transparent” relay station (RS), the network access control (MAC) message is transmitted to the mobile station only by the macro base station or through the relay station;

4) the relay station may have a function for calculating the measurement information of the code division multiple access (CDMA) signal or the channel state measurement information (CQI) for physical control; and

5) time planning can be carried out in central planning mode or in distributed planning mode.

In embodiments of the present invention, advanced relay stations (ARSs) can be subdivided into odd-hop ARSs and even-hop ARSs depending on the number of ABS hops. ARS with an odd number of hops and ARS with an even number of hops can have a hierarchical structure, and one network can include one or more ARS with an odd number of hops and one or more ARS with an even number of hops.

The frame structure used in the relay station may include a frame structure for the downlink and a frame structure for the uplink. In this case, the frame structure for the downlink includes an access area for a downlink (DL) and a relay zone for a downlink, while the frame structure for an uplink includes an access area for an uplink (UL) and a zone relay for uplink communication.

In this case, if there is one relay station (one hop structure) between the base station and the mobile station, the downlink access area is the interval within which the ARS transmits data packets, and the like, to AMS, and the uplink access area is the interval within which the AMS transmits data packets, and the like, to the ARS. ARS may also receive data packets from the ABS in the downlink relay zone and may transmit data packets to the ABS in the downlink relay zone.

The frame structure of the relay station in such a hopping structure is presented in figure 1 and figure 2.

FIG. 1 is a block diagram illustrating the frame structures of a relay station and a base station according to a frequency division duplex (FDD) mode in a typical IEEE.802.16m system, and FIG. 2 is a block diagram illustrating a frame structure of a relay station and base station according to the time division duplex (TDD) mode in a typical IEEE 802.16m system.

Figure 1 shows that the uplink and downlink are identified by frequency, and the access area and the relay zone within the same frame are respectively distributed across four subframes (SF). Also shown in FIG. 2, the uplink and downlink are identified by time division, and the access area and relay zone are again identified by time division within each uplink (UL) and downlink (DL). 1 and 2, a gap for displacing the respective zones is provided between the respective zones.

In the above frame structure, an ARS relay station can broadcast its system information through a superframe header (SFH) in a downlink access area. The relay station may also transmit system information consisting of the same fields as the fields in the SFH transmitted from the base station. In this case, the field values may differ from the values transmitted from the base station. However, the identifier field (i.e., the BSLD field) of the relay station includes its BS identifier, not the RS identifier. This is because a BS identifier rather than an RS identifier is required during the handover process in the mobile station.

The relay station includes additional system information not used by the ABS base station, in addition to the system information transmitted via SFH. Examples of additional system information include information indicating an access zone and a relay zone for uplink and downlink and the location and / or size of the gap existing between the respective zones.

A method for efficiently transmitting additional system information for a relay station to a mobile station or to a slave relay station according to one embodiment of the present invention will be described below.

The first implementation option

According to one embodiment of the present invention, there is provided a method for efficiently transmitting additional system information for a relay station to a mobile station or a slave relay station.

First of all, a method for reporting downlink information of each zone will be described according to one embodiment of the present invention.

The reason that information for each zone for the downlink must be communicated to the mobile station or the slave relay station is because the mobile station or slave relay station can recognize the data transmitted from the base station to the corresponding relay station as its data ( in fact, the data may be noise or interference). In addition, if the slave relay station knows the data or signal transmission zone transmitted through it, it should not read A-MAP information within the optional zone.

In this regard, this embodiment provides a method for reporting downlink / uplink zone information (relay zone information and access zone information) through an A-MAP zone in a downlink subframe. This method will be described with reference to figure 3 and figure 4.

FIG. 3 is a diagram illustrating an example of reporting zone information of a relay station via a zone map according to one embodiment of the present invention.

As shown in FIG. 3, the A-MAP zone of the first downlink subframe includes information about the type, length and gap of the current zone, and information about the type, length and gap of the next zone. The A-MAP zone of the subframe where the next zone begins includes information about the type, length and gap of the corresponding zone, and information about the type, length and gap of the next zone. Thus, if the relay station is operating in the receive mode (for example, in the relay zone for the downlink) in the next zone relative to the current zone, the mobile station or the slave relay station will be able to recognize that the signal of the corresponding zone is not intended for it, and will receive the signal from the corresponding relay station at the end of the next zone.

Although only a downlink subframe is shown in FIG. 3, the area information for the uplink may be included in the corresponding A-MAP uplink area.

FIG. 4 is a diagram illustrating another example of reporting zone information of a relay station via a zone map according to one embodiment of the present invention.

As shown in FIG. 4, in addition to the area information to which the corresponding subframe belongs, information for each area and gap information within the corresponding superframe may be transmitted to the A-MAP area of the first downlink subframe. In this case, if the mobile station or the slave relay station successfully receives the A-MAP zone of the first subframe, additional information for the next zone is not required.

Meanwhile, zone information and gap information in each zone can be transmitted through the A-MAP zone of each subframe.

Zone information and gap information in each zone can be transmitted through the SFH header, which transmits the necessary system information, or through an AAI_SCD message to transmit additional system information in addition to the A-MAP zone of each subframe. At the same time, the slave relay station should not allow the connection of the network of this slave relay station and the mobile station until it receives zone information and information about the gaps.

Next, a method for transmitting information about hops (an odd or even number of hops), a number of hops and a relay station identifier according to an embodiment of the present invention will be described. The relationship between the base station and the relay station and between the relay station and another relay station will be described with reference to FIG.

5 is a block diagram illustrating an example of building a network comprising a base station and a slave relay station.

Based on the assumption that the network structure corresponds to that shown in FIG. 5, the hop information can be subdivided into hop information between the base station and the relay station and between the relay station and another relay station.

1) In the relationship between ABS and ARS1, or between ABS and ARS2, when ARS1 or ARS2 indirectly determines its jump information or connects to ABS, then ABS can inform via the MAC control that the corresponding relay station is an odd number of jump stations.

2) In the relationship between ARS 1/2 and ARS 3/4, when ARS 1/2 transmits its jump information via SFH, ARS 3/4 indirectly determines its jump information, or when ARS 3/4 connects to ARS 1 / 2, ARS 1/2 can report its jump information to ARS 3/4 so that ARS 3/4 indirectly detects jump information, or it can directly report jump information through a MAC message. This is because ARS 1/2 knows that it belongs to stations with an odd number of hops, and ARS 3/4, which is a subordinate relay station of ARS 1/2, belongs to stations with an even number of hops.

Like the aforementioned method, the number of hops can be reported to the relay station via SFH transmitted from the upstream component of the system (i.e., from the base station or from the upstream relay station), or via the MAC message during the connection process. If SFH is used, the relay station can indirectly determine its number of hops by adding 1 to the number of hops of the superior component of the system. If a MAC message is used, the upstream component can report its number of hops to the subordinate component in the same way as SFH, or it can directly report the number of hops to the subordinate relay station.

Meanwhile, a relay station identifier is an identifier for identifying a relationship between a relay station and another relay station / other mobile station, for example, a relationship between ARS1 and ARS3 / AMS1. The relay station identifier may be a dedicated identifier assigned from the base station. In this case, the allocated identifier may be a station identifier (STID). In order to transmit such an identifier, a method for assigning an identifier to a relay station via a MAC control message when the relay station is connected to the base station can be used between the base station and the relay station with an odd number of hops. There is also a method of transmitting the identifier of the relay station assigned by the base station from the parent relay station to the slave relay station through the header of the superframe, or transmitting the identifier of the relay station to the slave relay station via the MAC control message when the slave relay station is connected to the parent relay station used between the upstream relay station and the slave relay station th.

Meanwhile, according to another aspect of the present invention, there is provided a method for efficiently receiving additional broadcast information of a base station in a relay station of a broadband wireless access system. First of all, additional broadcast information will be described.

In general, when communicating with mobile stations, the base station transmits additional broadcast information (ABI) to the mobile station as an additional broadcast message (e.g., AAI_SCD, AAI_NBR-ADV, AAI_PAG-ADV, AAI_MC-ADV, etc.). In this case, an additional broadcast message is transmitted through the information exchange channel, through which ordinary user data is transmitted. The ABI includes advanced system parameters, system configuration information, and control information for downlink (DL) notification.

The information contained in the ABI is required to collect system data as follows.

- Information for handover: the default HO RSSI (relative signal strength indicator) and CINR (signal-to-noise ratio taking into account interference) averaging parameter, hysteresis tolerance, time duration before switching on (Time-to-Trigger), switching information.

- Information for MIMO (Multiple Input, Multiple Output): a subset of the codebook for PMI coordination, a subset of the codebook for indicating DL MU-MIMO subsets.

- Information for relays: information on surges, DL / UL distribution, transmit / receive zone, zone type.

- Information for many carriers: carrier index, indication of a fully / partially configured carrier, center frequency, bandwidth information, initial accessibility, information on protection resources.

- Information for femtocells.

- Information for EMBS: service identifier, MSCCH resource allocation information.

- Information for inter-RAT: MIH capability support.

- Neighbor Notification Information: Characteristics of the neighboring BS.

- Control and signaling information can be transmitted in a downlink (DL) to provide network notifications to one user or group of users in standby or inactive mode.

The base station generally transmits an additional broadcast message to a downlink access area (i.e., in a data mode), this additional broadcast message including the above-mentioned additional broadcast information. In this case, the relay station also operates in the transmit (TX) mode while the base station is operating in the access area of the downlink. Accordingly, a method is required for efficiently receiving additional broadcast information (ABI) of a base station in a relay station when the additional broadcast information changes. Methods for efficiently receiving an ABI of a base station in a relay station according to another embodiment of the present invention will be described below.

Method 1

The base station (or upstream relay station) may additionally transmit an additional broadcast message through the downlink relay zone. Moreover, only in case of a change in the ABI, the base station (or a higher relay station) can transmit a message that includes the changed information to the relay zone for the downlink.

Method 2

The base station (or upstream relay station) can transmit an additional broadcast message only through the relay zone for the downlink.

Method 3

The relay station (or slave relay station) can report the number of changes in the ABI and SFH of the base station (or upstream relay station). If the corresponding relay station (or subordinate relay station) does not include the latest version system information, the base station (or upstream relay station) that received the number of changes transmits a message to the corresponding relay station, and this message includes the corresponding system information .

Method 4

The base station (or upstream relay station) may periodically transmit the number of ABI and SFH changes to the relay station (or slave relay station). If the relay station (or slave relay station) that has accepted the number of changes determines that the system information is newer than the system information transmitted / applied by the relay station, it may request information in a message that includes the corresponding system information.

In the above methods, the base station (or upstream relay station) may request the relay station (or subordinate relay station) whether this relay station (subordinate relay station) has received the corresponding message.

Second implementation option

According to another embodiment of the present invention, if the system information of the base station is changed, a method is provided for efficiently receiving the changed information in the relay station and updating the changed system information.

As described above, the relay station exchanges data with both the mobile station and the base station. However, since the relay station is synchronized with the base station, the relay station and the base station broadcast their system information at the same time. Accordingly, the relay station broadcasts its system information according to the transmission mode while the base station is transmitting system information. In this case, a problem arises that the relay station cannot receive the system information of the base station, as a result of which the relay station cannot update the system information. This problem also occurs in the upstream relay station and in the subordinate relay station.

Accordingly, in this embodiment, a separate MAC control message is determined, and the relay station receives the changed system information of the base station or the upstream relay station to update the changed system information.

System information updated at the base station may relate to necessary system information (ESI). The necessary system information is generally transmitted through a secondary superframe header (S-SFH) and can be identified by subpackets from subpacket 1 to subpacket 3 (i.e., S-SFH SP1, S-SFH SP2 and S-SFHSP3). These subpackets may have different transmission periods and may be updated separately by the base station.

The relay station can determine, through the number of SFH changes, whether the system information of the base station (or the upstream relay station) has been changed. The number of SFH changes of the base station (or upstream relay station) can be transmitted to the relay station (or slave relay station) through an advanced (A-MAP) MAP. In this case, the transmission zone of the number of SFH changes may be a non-user-specific zone (or an extended non-user-specific zone) or a user-specific zone. Meanwhile, the MAP zone may include information about the place of transmission of system information separately transmitted for the slave relay station in addition to information about the number of SFH changes. If the transmission location information is included in the A-MAP zone, the slave relay station will be able to determine if the corresponding information has been changed, and if the corresponding information has been changed, it will be able to try to update it.

1) Type of transmission of the MAC message

The type of MAC message (hereinafter referred to as “the message with the necessary system information for the relay station” or “RS-ESI message”) for transmitting the changed system information of the base station to the slave relay station may be a type of broadcast message or an additional broadcast message. In addition, ARS relay stations are grouped according to channel status, etc., and one multicast identifier (ID) is given to the same group. In this case, the type of MAC message may be a type of multicast message transmitted to relay stations having an appropriate ID, or a type of unicast message.

The corresponding message may not include information related to encryption and security, in contrast to the commonly used control message MAC.

2) MAC message type

Meanwhile, the RS-ESI message may be transmitted in one type of message, which includes system information within all SFHs, or may be transmitted such that system information inside the P-SFH and system information within each S-SFH SP is transmitted in accordance with each type of message. The MAC message may also indicate whether it includes each subpacket using a mapping bitmap, or may indicate that it includes a subpacket only having sets of bits. For example, if the display bitmap indicates 4 bits, then each bit can be allocated so that 1st bit: information inside PSFH, 2nd bit: information inside S-SFH SP1, 3rd bit: information inside S- SFH SP2 and 4th bit: information inside S-SFH SP3. However, since the P-SFH is loosely coupled to the necessary system information, after the display bitmap is set to 3 bits, subpackets 1 to 3 can be allocated. In addition, the MAC message for transmitting system information preferably includes numerical information, which is SFH version information.

In this case, the system information to be transmitted can be generated so as to exclude information such as the identifier of the base station (BS ID), which does not change, and optional information.

3) Timing relationships when transmitting a MAC message

The base station must transmit the appropriate message to the relay stations, observing the transmission timing below, as long as at least one relay station exists in the base station.

The timing relationships for RS-ESI transmission can be periodic, and the transmission period can be set independently or equal to the period of each subpacket SFH of the base station (N x PS-SFH SPx, N≥1). In this case, the base station can transmit scheduling information in time, such as information about the place of transmission and the period of the RS-ESI message, during connection to the network. In addition, the timing of the transmission of RS-ESI messages can be limited only by the request of the relay station.

According to other timing relationships when transmitting an RS-ESI message, the RS-ESI message can be transmitted from the base station in accordance with an event-triggered mode, provided that the system information is changed. In this case, the relay station may inform the base station whether a corresponding message has been received.

In order to inform the base station whether an RS-ESI message has been received, the relay station may use a header, such as an extended ACK message header (MAEN), or a MAC message, such as MR-Generic-ACK or AAI_MSG-ACK. If an ASK acknowledgment message is not received from a particular relay station, or if a message indicating a NACK message is received from a relay station, the base station can retransmit the message only to a specific relay station.

4) Timing relationships when applying updated system information

The relay station can directly apply the updated system information included in the RS-ESI message to the corresponding superframe in which the RS-ESI message is received, or it can pre-determine the frame or superframe to which the updated system information will be applied. In addition, information on time relationships during application can be included in all subpackages included in the RS-ESI message, thereby this information can be applied to all subpackages at the same time. Also, Information on time relationships when applied per subpackage can be included in the RS-ESI message, and these time relationships can be changed for each subpackage when applied. Such time relationships can be set in a super-frame block.

Table 1 below illustrates an example RS-ESI message according to another embodiment of the present invention.

Table 1 Name Size (bit) Explanation Message type 8 Super-frame number action field TBD
(= to be determined) LSBs of the TBD bits of the superframe number when subpackets (SPs) are to be applied The number of changes S-SFH four The number of S-SFH changes sent in this message S-SFH information display bitmap S-SFH information display bitmap Only when SP1 changes is the 1st bit set to 0b1. Only when SP2 changes is the 2nd bit set to 0b1. Only when SP3 changes is the 3rd bit set to 0b1. If (1st bit of the bitmap for displaying S-SFH information = 0b1) { SP1 information } If (2nd bit of the bitmap for displaying S-SFH information = 0b1) { SP2 information }

If (3rd bit of the bitmap for displaying S-SFH information = 0b1) { SP3 information }

As can be seen from table 1, the updated system information of the base station, which is included in the RS-ESI message, can be indicated through the 3-bit mapping bitmap field (S-SFH information mapping bitmap) by subpackets. In this case, the updated system information of the base station, which is included in the RS-ESI message, can be indicated using the type (0b00: SP1, 0b01: SP2, 0b10: SP3), instead of the bitmap of the type mapping (bitmap of the display of S-SFH information ) of 3 bits.

In addition, the number of secondary superframe headers (S-SFH change number) may be included in the system information to indicate the S-SFH number of the corresponding message. Meanwhile, the RS-ESI message may include a super-frame number action field to indicate when the system information (i.e., each sub-packet) included in the corresponding message is applied in the super-frame block.

Table 2 below illustrates another example RS-ESI message according to another embodiment of the present invention.

table 2 Name Size (bit) Explanation Message type 8 The number of changes S-SFH four The number of S-SFH changes transmitted in this message S-SFH information display bitmap Only when SP1 changes is the 1st bit set to 0b1. Only when SP2 changes is the 2nd bit set to 0b1. Only when SP3 changes is the 3rd bit set to 0b1. If (1st bit of the bitmap for displaying S-SFH information = 0b1) { SP1 information Super-frame number action field TBD (= to be determined) LSB of TBD bits of superframe number when SP1 is to be applied } If (2nd bit of the bitmap for displaying S-SFH information = 0b1) { SP2 information Super-frame number action field TBD LSB of TBD bits of superframe number when SP2 is to be applied } If (3rd bit of the bitmap for displaying S-SFH information = 0b1) { SP3 information Super-frame number action field TBD LSB of TBD bits of superframe number when SP3 is to be applied }

Table 2 basically coincides with table 1. However, in table 2, the action field of the superframe number is included in each subpacket, while the temporal relationships during application can change for each subpacket.

The RS-ESI message, which includes the information shown in table 1 and table 2, may further include information (for example, the initial offset of the allocated resources along the frequency axis, the location of the allocated resources along the time axis, etc.), indicating uplink resources allocated for transmitting a MAC message (eg, an AAI-MSG-ACK message) in order to determine whether a corresponding message has been received by a relay station that has additionally received an RS-ESI message. In this case, the allocation order of uplink resources can be determined by an increasing order or a decreasing order of RSID values.

A detailed application example of the above RS-ESI message will be described with reference to FIG.

6 is a flowchart illustrating an example of a procedure for updating system information of a base station in a relay station according to another embodiment of the present invention.

6, it is assumed that the RS-ESI format shown in Table 2 is used, and that the RS-ESI message is transmitted in accordance with an event-triggered mode based on the condition that the base station system information is updated. It is also assumed that the relay station uses an AAI_MSG-ACK message to inform the base station whether an RS-ESI message has been received.

As shown in FIG. 6, if the system information is updated in the ABS base station (step S601), then the base station can transmit the updated system information to the relay station via an RS-ESI message (step S602).

In this case, the base station can allocate resources for the uplink (UL grant for AAI_MSG-ACK or ASK grant) to the relay station for transmitting the AAI_MSG-ACK message, wherein the AAI_ASG-ACK message is intended by the relay station to inform the base station of the RS- transmission result ESI messages (step S603).

In this case, the UL grant, i.e., the ASK grant, will be described in more detail below.

The relay station that successfully received the RS-ESI message transmits the AAI_MSG-ACK message to the base station using the uplink resources indicated by the grant UL information, thereby notifying the base station that the RS-ESI message was successfully received (step S604 )

After that, the relay station can apply the update information of each subpacket corresponding to the bit set to “1” in the bitmap mapping (bitmap for displaying S-SFH information) included in the RS-ESI for each subpacket in the superframe specified in the action field of the superframe number included in the update information of each subpacket (step S605).

If the AAI_MSG-ACK message was not received in step S604, the base station may retransmit the RS-ESI message to the relay station. In this case, a retransmission may occur before the point in time indicated by the action field of the super-frame number.

An example of an uplink resource transmission (grant UL for AAI_MSG-ACK or grant ACK) for an AAI_MSG-ACK message from a base station to a relay station according to another embodiment of the present invention will be described in detail.

1) Transmission of the ACK of the provision through an advanced (advanced) information display element (A-MAP IE).

If the ACK provision includes the selected information only for transmitting the ACK message from the relay station (or the slave relay station) to the base station (or the upstream relay station), an example A-MAP-IE for transmitting the ACK provision from the base station to all relay stations, associated with it will be described with reference to table 3 below.

Table 3 Name Size (bit) Explanation Type A-MAP IE four Initial Resource Offset (Initial LRV Index) TBD (= to be determined) Selection Size TBD TTI Duration one Mcrc Broadcast Masked CRC

As follows from Table 3, the MAP IE, which includes the provision ACK information, may include resource allocation information (i.e., initial offset and allocation size) that can be used by all relay stations associated with the base station. In this case, the display CRC may be masked by the broadcast identifier.

If a relay station is assigned to which resources will be allocated for transmitting the ACK message, a mapping bitmap can be used, and IE MAP for this case can be represented by Table 4 below.

Table 4 Name Size (bit) Explanation Type A-MAP IE four ARS Number TBD (= to be determined) ARS bitmap display ARS Number Initial Resource Offset (Initial LRV Index) Selection Size TBD TTI Duration one Mcrc Masked Broadcast Identifier (ID) CRC

As follows from table 4, the display bitmap field indicating the relay station to which resources are allocated is included in the MAP IE. Moreover, the distribution order of each field of the display bitmap may be determined by RSID.

2) Transmission of ASK provision through A-MAP IE using a multicast identifier (ID)

Below, it will be described with reference to table 5 and table 6, the MAP IE type used in the design to allocate ACKs to all relay stations having a specific multicast ID. In this case, it should be noted that the multicast ID is the same as for the RS-ESI message.

Table 5 Name Size (bit) Explanation Type A-MAP IE four Initial Resource Offset (Initial LRV Index) TBD (= to be determined) Selection Size TBD TTI Duration one Mcrc CRC masked multicast ID

In Table 5, the IE MAP, which includes the provision ACK information, is similar to that shown in Table 3, but the CRC is masked by a multicast ID. In this case, the relay station can determine through the MCRC information that the corresponding MAP IE includes provision ACK information for this multicast ID.

If a relay station is assigned to which resources are allocated for transmitting the ACK message, a mapping bitmap can be used, and IE MAP for this case can be expressed in Table 6 below.

Table 6 Name Size (bit) Explanation Type A-MAP IE four Total number RS TBD RS bitmap display Total number RS Initial Resource Offset (Initial LRV Index) TBD Selection Size TBD TTI Duration one Mcrc CRC masked multicast ID

As follows from table 6, the display bitmap field indicating the relay station to which resources are allocated is included in the MAP IE. Moreover, the distribution order of each field of the display bitmap may be determined by RSID.

Meanwhile, IE MAP may indicate the relay station to which the ACK grant is allocated, in accordance with the hierarchical display bitmap. This will be described with reference to table 7 below.

Table 7 Name Size (bit) Explanation Type A-MAP IE four First Level Display Bitmap Size TBD (= to be determined) Level 1 Mapping Bitmap First Level Display Bitmap Size For (i = 0; size (first level display bitmap); i +) { If (first level display bitmap [i] = 1) { ARS bitmap display TBD } Initial Resource Offset (Initial LRU Index) 7 Selection Size TBD TTI Duration one Mcrc CRC masked multicast ID

As follows from Table 7, the MAP IE for allocating an ACK grant includes a first level mapping bitmap field and a relay station mapping (ARS) bitmap field.

The first level display bitmap field indicates an ARS ID range. For example, it is believed that the range is determined in a block of 10. In this case, if the first bit is 1, then each bit of the relay map display bitmap means relay stations having identifiers (IDs) from 0b × 0000001 to 0b × 0001010. If the second bit is 1, each bit of the relay map display bitmap means a relay station having an ID from 0b × 0001011 to 0b × 0010100.

If a relay station mapping bitmap field is not included in the MAP IE, this may mean that it is distributed to all ARSs within the corresponding range.

In addition, to indicate the relay station to which the ACK grant is allocated, a method of indicating the ID of the initial relay station and the number of relay stations to which the ACK grant is allocated can be used. This will be described with reference to table 8.

Table 8 Name Size (bit) Explanation Type A-MAP IE four Start number ARS ID TBD ARS Number TBD Initial Resource Offset (Initial LRV Index) 7 Selection Size TBD TTI Duration one Mcrc CRC masked multicast ID

As follows from table 8, the field of the initial number of the ARS ID and the field of the number of ARS can be included in the MAP IE to allocate ACK provision, to indicate the relay station, which is allocated ACK provision.

For example, if the initial ARS ID field is 0b × 0011101 and the ARS number field is 2, this indicates that the corresponding provision is allocated to relay stations having IDs 0b × 00111001 and 0b × 0011110.

Each field included in the A-MAP IE for allocating an ACK grant may be included in a given control MAC message. In addition, if the ACK grant is not allocated to the corresponding relay station before the expiration of a predetermined time (determined by the timer or the duration of, for example, the next super-frame, etc.), the relay station may request an uplink resource for transmitting the ACK message through a random access process. In this case, if there is a suitable resource, the relay station can transmit the ACK message to the base station (or upstream relay station) through the corresponding resource, without waiting for the allocation of any resource for the uplink through the random access process or ASK provision.

Next, a method for allocating a multicast ID and RSID according to another embodiment of the present invention will be described.

1) RSID

The RSID is aimed at identifying relay stations in the relationship between the base station / upstream relay station and the slave relay station. The base station / upstream relay station may assign such an RSID during the initial connection process of the slave relay station. In this case, the assigned ID may be a station identifier (STID) consisting of 12 bits.

2) Multicast ID

The base station and the upstream relay station must transmit the modified SFH information to their subordinate relay stations. In this case, the RS-ESI message, which includes the corresponding modified SFH information, can be transmitted to the slave relay station in multicast mode. Accordingly, the base station and the upstream relay station can assign the multicast identifier (ID) of all the subordinate stations through the ARS configuration process, that is, through the RS configuration command message.

Next, a method for assigning a multicast ID according to another embodiment of the present invention will be described in more detail.

According to this embodiment, the x-bit MSB value of the slave relay station having one multicast ID can be set to the x-bit MSB value of the multicast ID. This will be described with reference to FIG.

7 is a flowchart illustrating an example of a method for configuring a relay station identifier (RSID) and a multicast identifier (multicast ID) according to another embodiment of the present invention.

In Fig. 7, it is assumed on the left that the multicast ID is 111010000000 and x is 5. In this case, the RSID inside the corresponding multicast ID is in the range from 111010000001 to 111011111111. It is also believed that the ID on the right is 111100000000 and x is 5. In this case, the RSID of the corresponding the multicast ID ranges from 111100000001 to 111101111111. In FIG. 7, the base station assigns the ID of each relay station in ascending order. However, this is just an example, and RSID assignment can occur in descending order.

The base station and the upstream relay station may report whether a message has been received (i.e., an RS-ESI message) transmitted via a multicast ID. In this case, since the base station and the upstream relay station can determine the total number of slave relay stations that exist within the corresponding ID, they can allocate the corresponding uplink resources to notify (ACK) of the receipt of the corresponding message taking into account the number of slave relay stations via RS -ESI message or A-MAP IE.

Mobile station and base station configuration

Next will be described, as another warrant for the implementation of the present invention, a mobile station (MS) and a femtocell base station (FBS) through which embodiments of the present invention can be implemented.

The mobile station acts as a transmitter in the uplink, while the mobile station acts as a receiver in the downlink. Also, the base station acts as a receiver in the uplink, while the base station acts as a transmitter in the downlink. In other words, both the mobile station and the base station may include a transmitter and a receiver for transmitting and receiving information or data.

The transmitter and receiver may include a processor, module, part and / or means for which embodiments of the present invention are implemented. In particular, the transmitter and receiver may include a module (means) for encoding messages, a module for decoding encoded messages, an antenna for transmitting and receiving messages. An example of a transmitter and a receiver will be described with reference to FIG.

FIG. 8 is a block diagram illustrating an example of a transmitter and a receiver according to another embodiment of the present invention.

8, the structure of the transmitter is shown on the left side, while the structure of the receiver is shown on the right side. Both the transmitter and the receiver can include an antenna 5, 10, a processor 20, 30, a transmitting (Tx) module 40, 50, a receiving (Rx) module 60, 70, and a storage device 80, 90. The corresponding elements can perform functions, inherent to these interacting components. These corresponding elements will now be described in more detail.

Antenna 5, 10 is used to transmit to the external medium a signal generated by the Tx module 40, 50, or to receive a radio signal from the external medium to transmit this radio signal to the Rx module 60.70.

If the MIMO (multi-channel input-multi-channel output) function is supported, two or more antennas can be provided. An antenna, a TX module, and an Rx module can form a radio frequency (RF) module.

The processor 20, 30 generally controls the entire operation of the mobile station. For example, the processor 20, 30 may perform the function of a controller for implementing the aforementioned embodiments, a network access (MAC) function with the management of personnel variables in accordance with the operational characteristics and state of the radio wave, a handover function, authentication and encryption functions, and the like. More specifically, the processor 20, 30 may exercise overall control to perform the above system information transfer / update procedure.

In particular, the relay station processor controls the radio module to receive RS-ESI messages from the base station and acquires updated base station system information that is included in the RS-ESI message. The processor of the relay station can implement the updated system information in the subpacket block in compliance with the corresponding time relationships using a field indicating the update time per subpacket. The relay station processor may also control the radio module to transmit the AAI_MSG-ACK message to the base station, thereby informing the base station that the AAI_MSG-ACK message has been successfully received. In this case, the uplink resource for transmitting the AAI_MSG-ACK message can be allocated through the MAC control message or the A-MAP IE CRC masked by the given broadcast ID or multicast ID.

In addition, the processor of the relay station can provide full control over the execution of the processes described in the above embodiments.

Tx module 40, 50 performs the specified coding and modulation of data that arrives in the specified sequence from processor 20, 30 and then is transmitted to the external environment, after which it transmits encoded and modulated data to antenna 10.

The Rx module 60, 70 performs decoding and demodulation of the radio signal received from the external environment through the antenna 5, 10 to restore the original data, and then transfers the restored data to the processor 20, 30.

A storage device 80, 90 may store a program for processing and controlling the processor 20, 30, or may perform the function of temporarily storing input / output data (ESI information, etc.). The storage device 80, 90 may also include at least one of the following types of memory: flash memory, hard disk, multimedia micro-memory card, memory card (e.g., SD or XD memory), random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, magnetic disk and optical disk.

Meanwhile, the base station and the relay station perform a control function for performing the above embodiments of the present invention, orthogonal frequency division multiple access (OFDMA) packet scheduling, packet scheduling, and time division duplex (TDD) channel multiplexing, network access function (MAC) with control of personnel variables in accordance with operational characteristics and the state of the radio wave, three real-time message flow control, a handover function, an authentication and encryption function, a modulation and demodulation function of data packets, a fast encoding function of packet transmission channels and a real-time modem control function through at least one of the above-mentioned modules, or additionally includes a means, module or part for performing the above functions.

Specialists in the art should understand that the present invention can be implemented in other specific forms without deviating from the essence and essential characteristics of the invention. So the above implementation options should be considered in all respects as illustrative and not restrictive. The scope of the invention should be determined by a reasonable interpretation of the attached claims, and all changes that occur within the equivalent scope of the invention are included in the scope of this invention.

Industrial applicability

Embodiments of the present invention are applicable to various wireless access systems including a 3GPP system, a 3GPP2 system and / or an IEEE 802.xx system. In addition to these wireless access systems, embodiments of the present invention are applicable to all technical fields in which wireless access systems are used.

Specialists in the art will understand that the present invention can be carried out in other specific ways, different from those described here, without deviating from the essence and essential characteristics of the present invention. Therefore, the above implementation options should be considered in all respects as illustrative and not restrictive. The scope of the invention should be determined by the attached claims and their acceptable equivalents, and not the above description, and all changes that occur within the meaning and equivalence of the attached claims are intended to be covered by it. For specialists in the art, it is obvious that the claims that are not explicitly mentioned one in another in the attached claims, can be presented in combination with each other as an example of a variant of implementation of the present invention or are included here as a new paragraph with subsequent correction after applying.

Claims (15)

1. A method for updating system information of an advanced base station (ABS) in an advanced relay station (ARS) of a broadband wireless access system, the method comprising:
receiving a first message including changed information of the base station system information from the base station;
transmitting a second message to confirm receipt of the first message to the base station;
applying modified information; and
relaying data received from the base station to the mobile station using system information updated in accordance with the changed information. 2. The method according to claim 1, in which the system information includes a first subpacket, a second subpacket and a third subpacket, and
wherein the changed information includes a change count field indicating the number of system information changes, a display bitmap field indicating whether each of the subpackets is included in the first message by using 1 bit, and update information of each subpacket corresponding to the bit set to the state “1” in the display bitmap field. 3. The method according to claim 2, in which the changed information further includes a super-frame number action field indicating the time when the update information included in the first message is applied in the super-frame block, and
in which the step of applying the changed information is performed at a point in time indicated by the action field of the super-frame number. 4. The method of claim 1, wherein the first message is received from the base station when system information changes. 5. The method according to claim 1, in which the first message is a message with the necessary information for the advanced relay station, and the second message is a message from the ACK message. 6. A method for updating system information of an advanced base station (ABS) in an advanced relay station (ARS) in a broadband wireless access system, the method comprising:
transmitting the first message, including the changed information of the system information of the base station, to the relay station; and
receiving a second message from the relay station to confirm receipt of the first message,
transmission to the relay station of data that must be relayed to the mobile station in accordance with the changed system information information. 7. The method according to claim 6, in which the system information includes a first subpacket, a second subpacket and a third subpacket,
wherein the changed information includes a change count field indicating the number of changes to the system information, a display bitmap field indicating whether each of the subpackets is included in the first message by using 1 bit, update information of each subpacket corresponding to the bit set to “1 ”In the display bitmap field, and the super-frame number action field indicating the time when the update information included in the first message is applied in the super-frame block. 8. The method according to claim 6, in which the first message is transmitted when the system information changes. 9. The method according to claim 6, which further comprises retransmitting the first message to the relay station, if the second message is not received from the relay station. 10. The method according to claim 6, in which the first message is a message with the necessary system information for the advanced relay station, and the second message is a message from the ACK message. 11. An advanced relay station (ARS) operating in a broadband wireless communication system, the relay station comprising:
CPU; and
a radio frequency (RF) module transmitting and receiving a radio signal to / from an external environment under the control of a processor,
moreover, the processor receives the modified system information of the advanced base station (ABS) through the first message received from the base station, controls the second message to confirm the receipt of the first message to be transmitted to the base station, by controlling the RF module, controls the application of the changed information, which must be applied and manages data received from the base station, which must be relayed to the mobile station using system information, updated hydrochloric according to the changed information. 12. The relay station according to claim 11, in which the system information includes a first subpacket, a second subpacket and a third subpacket, and
wherein the changed information includes a change count field indicating the number of changes to the system information, a display bitmap field indicating whether each of the subpackets is enabled by using 1 bit, and update information of each subpacket corresponding to a bit set to “1” in display bitmap field. 13. The relay station of claim 12, wherein the changed information further includes a super-frame number action field indicating a time when update information included in the first message is applied in the super-frame block, and
in which the processor controls the application of the changed information that must be executed at the time indicated by the action field of the superframe number. 14. The relay station of claim 11, wherein the first message is transmitted from the base station when system information changes. 15. The relay station according to claim 11, in which the first message is a message with the necessary information for the advanced relay station, and the second message is a message from the ACK message.

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