TECHNICAL FIELD

The present invention relates to a wireless communication method and a wireless communication terminal using a BSS identifier.

BACKGROUND ART

In recent years, with supply expansion of mobile apparatuses, a wireless communication technology that can provide a rapid wireless Internet service to the mobile apparatuses has been significantly spotlighted. The wireless communication technology allows mobile apparatuses including a smart phone, a smart pad, a laptop computer, a portable multimedia player, an embedded apparatus, and the like to wirelessly access the Internet in home or a company or a specific service providing area.

One of most famous wireless communication technology is wireless LAN technology. Institute of Electrical and Electronics Engineers (IEEE) 802.11 has commercialized or developed various technological standards since an initial wireless LAN technology is supported using frequencies of 2.4 GHz. First, the IEEE 802.11b supports a communication speed of a maximum of 11 Mbps while using frequencies of a 2.4 GHz band. IEEE 802.11a which is commercialized after the IEEE 802.11b uses frequencies of not the 2.4 GHz band but a 5 GHz band to reduce an influence by interference as compared with the frequencies of the 2.4 GHz band which are significantly congested and improves the communication speed up to a maximum of 54 Mbps by using an Orthogonal Frequency Division Multiplexing (OFDM) technology. However, the IEEE 802.11a has a disadvantage in that a communication distance is shorter than the IEEE 802.11b. In addition, IEEE 802.11g uses the frequencies of the 2.4 GHz band similarly to the IEEE 802.11b to implement the communication speed of a maximum of 54 Mbps and satisfies backward compatibility to significantly come into the spotlight and further, is superior to the IEEE 802.11a in terms of the communication distance.

Moreover, as a technology standard established to overcome a limitation of the communication speed which is pointed out as a weak point in a wireless LAN, IEEE 802.11n has been provided. The IEEE 802.11n aims at increasing the speed and reliability of a network and extending an operating distance of a wireless network. In more detail, the IEEE 802.11n supports a high throughput (HT) in which a data processing speed is a maximum of 540 Mbps or more and further, is based on a multiple inputs and multiple outputs (MIMO) technology in which multiple antennas are used at both sides of a transmitting unit and a receiving unit in order to minimize a transmission error and optimize a data speed. Further, the standard can use a coding scheme that transmits multiple copies which overlap with each other in order to increase data reliability.

As the supply of the wireless LAN is activated and further, applications using the wireless LAN are diversified, the need for new wireless LAN systems for supporting a higher throughput (very high throughput (VHT)) than the data processing speed supported by the IEEE 802.11n has come into the spotlight. Among them, IEEE 802.11ac supports a wide bandwidth (80 to 160 MHz) in the 5 GHz frequencies. The IEEE 802.11ac standard is defined only in the 5 GHz band, but initial 11ac chipsets will support even operations in the 2.4 GHz band for the backward compatibility with the existing 2.4 GHz band products. Theoretically, according to the standard, wireless LAN speeds of multiple stations are enabled up to a minimum of 1 Gbps and a maximum single link speed is enabled up to a minimum of 500 Mbps. This is achieved by extending concepts of a wireless interface accepted by 802.11n, such as a wider wireless frequency bandwidth (a maximum of 160 MHz), more MIMO spatial streams (a maximum of 8), multi-user MIMO, and high-density modulation (a maximum of 256 QAM). Further, as a scheme that transmits data by using a 60 GHz band instead of the existing 2.4 GHz/5 GHz, IEEE 802.11ad has been provided. The IEEE 802.11ad is a transmission standard that provides a speed of a maximum of 7 Gbps by using a beamforming technology and is suitable for high bit rate moving picture streaming such as massive data or non-compression HD video. However, since it is difficult for the 60 GHz frequency band to pass through an obstacle, it is disadvantageous in that the 60 GHz frequency band can be used only among devices in a short-distance space.

Meanwhile, in recent years, as next-generation wireless communication technology standards after the 802.11ac and 802.11ad, discussion for providing a high-efficiency and high-performance wireless communication technology in a high-density environment is continuously performed. That is, in a next-generation wireless communication technology environment, communication having high frequency efficiency needs to be provided indoors/outdoors under the presence of high-density terminals and base terminals and various technologies for implementing the communication are required.

Especially, as the number of devices using a wireless communication technology increases, it is necessary to efficiently use a predetermined channel Therefore, required is a technology capable of efficiently using bandwidths by simultaneously transmitting data between a plurality of terminals and base terminals.

DISCLOSURE

Technical Problem

An object of an embodiment of the present invention is to provide a wireless communication terminal using a BSS identifier.

Technical Solution

According to an embodiment of the present invention, a base wireless communication terminal communicating wirelessly includes a transceiver configured to transmit and receive wireless signals; and a processor configured to process the wireless signals. The processor may be configured to: generate a trigger frame for triggering uplink transmission based random access of at least one wireless communication terminal, and insert the trigger frame into a physical layer protocol data unit (PPDU) to transmit the PPDU.

When the trigger frame triggers uplink transmission based random access of a wireless communication terminal unassociated with a Basic Service Set (BSS) operated by the base wireless communication terminal, the processor may be configured to transmit the PPDU using a PPDU format including a field indicating a BSS color. In this case, the BSS color may be a kind of identifier for identifying the BSS.

In more detail, when the trigger frame triggers uplink transmission based random access of a wireless communication terminal unassociated with a BSS operated by the base wireless communication terminal, the processor may transmit the PPDU using a high efficiency (HE) PPDU format.

In another specific embodiment, when the trigger frame triggers uplink transmission based random access of a wireless communication terminal unassociated with a BSS operated by the base wireless communication terminal, the processor may be configured to insert a field indicating a BSS color in the trigger frame. In this case, the BSS color may be a kind of identifier for identifying the BSS.

Specifically, the processor may be configured to insert a field representing the BSS color into a User Info field signaling information that is individually applied to the one or more wireless communication terminals for which the trigger frame triggers transmission. In another specific embodiment, a field indicating the BSS color may be inserted into a Common Info field for signaling information that is commonly applied to the one or more wireless communication terminals for which the trigger frame triggers transmission.

The processor may be configured to set a specific field of the trigger frame to a value of a predetermined Association ID (AID) to trigger random access of a wireless communication terminal unassociated with a BSS operated by the base wireless communication terminal.

The processor may be configured to transmit the trigger frame based on a predetermined schedule. In this case, the trigger frame triggers uplink transmission based random access of a wireless communication terminal performing a power saving operation based on the predetermined schedule.

In more detail, the processor may be configured to set a Receiver Address (RA) field of the trigger frame to a group address indicating a wireless communication terminal performing a power saving operation based on the predetermined schedule.

In another specific embodiment, the trigger frame may include a User Info field for signaling information that is individually applied to the one or more wireless communication terminals to trigger transmission, and the processor may be configured to set a value of an association ID (AID) indicated by a User Info field corresponding to a frequency band allocated for the uplink transmission based random access to a predetermined value indicating a wireless communication terminal performing a power saving operation based on the predetermined schedule. In this case, the predetermined value may be a reserved value that is not allocated for another purpose.

In another specific embodiment, the trigger frame may include a User Info field for signaling information that is individually applied to the one or more wireless communication terminals to trigger the transmission, and the processor may set a TID Aggregation limit field included in a User Info field corresponding to a frequency band allocated for the uplink transmission based random access to a predetermined value indicating a wireless communication terminal performing a power saving operation based on the predetermined schedule. In this case, the TID Aggregation limit field may be a field used to indicate the limit of the number of TIDs corresponding to data that can be aggregated in an A-MPDU transmitted based on the trigger frame.

According to an embodiment of the present invention, a wireless communication terminal wirelessly communicating with a base wireless communication terminal includes a transceiver configured to transmit and receive wireless signals; and a processor configured to process the wireless signals. The processor may be configured to: receive a physical layer protocol data unit (PPDU) including a trigger frame for triggering transmission to the base wireless communication terminal, and transmit the trigger-based PPDU based on the trigger frame.

When the PPDU including the trigger frame indicates a Basic Service Set (BSS) color, the processor may be configured to set a value of a BSS color indicated by the trigger-based PPDU based on the value of the BSS color indicated by the PPDU including the trigger frame. In this case, the BSS color may be one of identifiers identifying a BSS.

In addition, if the PPDU including the trigger frame does not indicate a BSS color, the processor may be configured to set a value of a BSS color indicated by the trigger-based PPDU according to an active BSS color of the wireless communication terminal. In this case, the active BSS color may indicate a BSS color actually used by the wireless communication terminal.

The processor may be configured to receive information on a BSS color change from the base wireless communication terminal. In this case, when a BSS color change time point indicated by the information on the BSS color change is reached, the processor may be configured to set the active BSS color to a value of a BSS color indicated by the information on the BSS color change.

The BSS color change time point may be set based on a target beacon transmission time transmitted by the base wireless communication terminal.

If the PPDU indicates a partial BSS color using a Partial Association ID (AID) field, the processor may determine whether the PPDU is an Intra-BSS PPDU or an Inter-BSS PPDU based on the partial BSS color when the value of the partial AID field is non-zero. In this case, the partial AID field may be a signaling field used to indicate part of an AID value. In addition, the Intra-BSS PPDU may be a PPDU transmitted from a BSS including the wireless communication terminal, and the Inter-BSS PPDU may be a PPDU transmitted from a BSS not including the wireless communication terminal.

According to an embodiment of the present invention, an operation method of base wireless communication terminal communicating wirelessly includes generating a trigger frame for triggering uplink transmission based random access of at least one wireless communication terminal; and inserting the trigger frame into a physical layer protocol data unit (PPDU) to transmit the PPDU.

The transmitting the PPDU may include, when the trigger frame triggers uplink transmission based random access of a wireless communication terminal unassociated with a Basic Service Set (BSS) operated by the base wireless communication terminal, transmitting the PPDU using a PPDU format including a field indicating a BSS color of a Basic Service Set (BSS) operated by the base wireless communication terminal. The BSS color may be a kind of identifier for identifying a BSS.

Advantageous Effects

An embodiment of the present invention provides a wireless communication method using a BSS identifier and a wireless communication terminal using the same.

