KR102061499B1 - Wireless communication system using semi mobile base station and method for providing wireless communication service - Google Patents

Abstract

The present invention discloses a wireless communication system and a method for providing a wireless communication service using a semi-mobile base station. The present invention provides at least one mobile communication terminal provided with a wireless communication service; At least one fixed base station connected to at least one of a wired and wireless backbone network and having a plurality of antennas to perform wireless communication using an ultrahigh frequency of a first frequency band; And a plurality of semi-mobile base stations each having a plurality of antennas, and performing wireless communication using the ultra high frequency with the at least one mobile communication terminal and the at least one fixed base station. The quasi-mobile base station provides a wireless communication system for performing massive MIMO communication using a second frequency band of a lower frequency band than the first frequency band.

Description

WIRELESS COMMUNICATION SYSTEM USING SEMI MOBILE BASE STATION AND METHOD FOR PROVIDING WIRELESS COMMUNICATION SERVICE}

The present invention relates to a wireless communication system and a method for providing a wireless communication service, and more particularly, to a wireless communication system and method using a semi-mobile base station.

BACKGROUND With the proliferation of portable mobile terminals such as smart phones and smart pads, the demand for wireless mass data transmission is increasing. The next generation mobile communication network infrastructure aims to secure 1000 times the capacity of the current communication capacity of about 100 Mbps. This is the capacity considering the traffic demand after 10 years in consideration of the increase of traffic twice a year. In order to increase the current data transmission capacity to the current 1000 times, the development of contents, platform, network, and terminal is required. Bottlenecks are very likely in the world.

 In current wireless communication systems, a large number of small cells are needed to increase data transmission capacity of a network. However, small cells such as macro cell base stations, WLANs, and femtocells all have to be connected by wired optical cables, which causes problems in terms of installation location and cost.

Nevertheless, high-capacity wireless backhaul, such as LMDS / LMCS (Local Multipoint Distribution Services / Local Multipoint Communication Services), is designed only for fixed base stations, thus avoiding the problem of the location and cost of the small cell. There is a limit that cannot be solved.

Although WiBro (Wireless Broadband Internet) terminals are currently used as wireless backhaul to support wireless LAN in a vehicle, capacity limitations due to the frequency band used have not been overcome.

An object of the present invention is to provide a wireless communication system using a quasi-mobile base station so that a number of quasi-mobile base stations that can utilize the existing various frequency bands together, and is not limited to the installation site or installation cost to transmit data cooperatively. have.

Another object of the present invention is to provide a method for providing a wireless communication service using a semi-mobile base station.

In order to achieve the above object, the present invention provides at least one quasi-mobile communication terminal provided with a wireless communication service; At least one fixed base station connected to at least one of a wired and wireless backbone network and having a plurality of antennas to perform wireless communication using a frequency of a cellular / mmWave / Terahertz band; And a plurality of semi-mobile base stations, each of which includes a plurality of antennas, performs wireless communication using the ultra-high frequency with the at least one quasi-mobile communication terminal and the at least one fixed base station. Two semi-mobile base stations provide multi-user beamforming communication using Cellular / mmWave / Terahertz / visible light frequency bands with each other.

In addition, the present invention is characterized in that the at least one fixed base station performs a wireless communication using the ultra-high frequency using a beamforming technique for the quasi-mobile base station in which LoS is secured among the plurality of quasi-mobile base stations.

In addition, the present invention is characterized in that the plurality of semi-mobile base station is installed in a building or a portable terminal performs the same function.

The present invention is not limited to the above-described embodiment, and as can be seen in the appended claims, modifications can be made by those skilled in the art to which the present invention pertains, and such modifications are within the scope of the present invention. Reveal it.

Accordingly, the wireless communication system and the method for providing a wireless communication service using the quasi-mobile base station of the present invention includes a plurality of quasi-mobile base stations, and the plurality of quasi-mobile base stations perform cooperative communication, thereby providing a small cell base station. It is not restricted by installation location and installation cost. Therefore, the quasi-mobile base station can be easily installed in various objects in the building to provide a communication capacity linearly proportional to the number of base stations without a communication shadow area. In addition, it supports multiband and multimode using existing communication bands of 5GHz and below and tens of GHz to 10 THz bands, so that existing mobile communication networks can be utilized together. Therefore, a large data communication infrastructure can be provided to a plurality of mobile communication terminals.

1 illustrates a concept of a wireless communication system using a semi-mobile base station according to the present invention.
2 shows a change in communication capacity according to the number of base stations for each communication scheme.
3 shows a change in communication capacity through cooperative communication of a semi-mobile base station.
4 shows an example of the operation of the wireless communication system of the present invention.
5 illustrates a method for providing a wireless communication service using a semi-mobile base station according to an embodiment of the present invention.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In addition, in order to clearly describe the present invention, parts irrelevant to the description are omitted, and the same reference numerals in the drawings indicate the same members.

Throughout the specification, when any part includes which component, which means that the component may further include other components, unless specifically stated otherwise. In addition, the following descriptions are given in the specification: ???????????????????????????? The term "e.g." denotes a unit for processing at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software.

1 illustrates a concept of a wireless communication system using a semi-mobile base station according to the present invention.

As shown in FIG. 1, the backhaul network in the present invention is a network providing a wired or wireless backhaul to a user through a plurality of Backbone Contents Switch (BCS), Access Contents Switch (ACS), and an Access Antenna (AA). As the BCS and the ACS, the ACS and the access antenna AA are interconnected to form a hierarchical backhaul network. Data servers are connected to some BCS and ACS in order to reduce the transmission time according to the user's content request and reduce the traffic load of the backbone.

 A plurality of access antennas (AA) are connected to a plurality of BBS (Building Base Station) and user terminals through a DLAN to provide communication capacity, BCS through a wired or wireless connection in a network configuration of a mixed star and tree topology / ACS-based backhaul network is dynamically distributed to a plurality of BBS and user terminals.

BANET is a building ad-hoc network, which means a semi-mobile base station installed in a building. In general, a base station installed in a building provides a wireless communication service by being fixed at a specific location of a building in the form of a fixed base station and receiving a wired backhaul, but the base station of the BANET of the present invention receives a wired and wireless backhaul from a backhaul network. It is configured to be freely installed and mobile even in the building. That is, a base station in a building may be fixed to a specific location of a building by receiving a wired backhaul or a wireless backhaul and may be implemented to move.

In the present invention, the base station installed in the building as described above is called a building base station (BBS). BBS provides a large capacity communication service to the terminal of the user in the building or building. BBS is implemented to enable direct communication with the access antenna (AA) to receive wired and wireless backhaul from the backhaul network.

The DLAN (Dynamic Link Access Network) forms a connection network between the access antenna (AA) and the BBS and the user terminal, and provides a large communication resource with the BBS of the BANET, while providing a relatively low capacity communication resource with the user terminal. to provide.

As described above, in the wireless communication system of the present invention, a BBS is provided in a building and receives a wireless backhaul from a backhaul network to provide a wireless communication service. Due to the nature of the wireless backhaul, the base station itself can be freely moved, unlike the existing fixed base station in the base station, the BBS of the present invention can be installed freely without being restricted by the installation place, and the installed place itself may move.

 Thus, as shown in Figure 1, even if installed in a fixed place, such as indoors, the user can freely move the location of the base station as needed. That is, the semi-mobile base station may be installed in various things.

In addition, the user may carry the BBS directly. This means that the base station itself can be combined with the user's portable terminal, and the user's portable terminal can also function as a base station.

In addition, as shown in FIG. 1, in the wireless communication system of the present invention, a plurality of BBSs may cooperate to support a user or configure an ad-hoc network with a user's portable terminal to perform cooperative communication. . As a plurality of BBSs can perform cooperative communication, the data transmission capacity of the wireless communication system may increase linearly in proportion to the number of base stations.

As described above, since the BBS is portable by the user and is capable of cooperative communication, the BBS changes in transmission capacity in each region according to the movement of the BBS. In other words, the more users, the greater the number of base stations. In addition, since the data transmission capacity increases linearly in proportion to the number of BBSs, the wireless communication system of the present invention can actively cope with the increase in network traffic by increasing the transmission capacity in a densely populated area.

In addition, the wireless communication system of the present invention may be operated in parallel with a fixed base station using a conventional wired or wireless backhaul, instead of using only a semi-mobile base station such as BBS. In addition, since the BBS may use a wired backhaul, the BBS may function as a fixed base station.

In addition, in the present invention, the BBS is configured to support frequencies of various frequency bands, and a second frequency band in addition to a next generation mobile communication network using a first frequency band (for example, a frequency band of 5 GHz to 10 THz and a visible light band). For example, existing mobile communication networks using frequency bands of 5 GHz or less can be used together. In addition, it is configured to utilize a WLAN network such as WiBro.

That is, the wireless communication system according to the present invention not only uses a frequency band of 5 GHz or more, but also utilizes all kinds of frequency bands of 5 GHz or less used by a conventional mobile communication network, unlike a conventional wireless communication system using a designated frequency band. do.

2 shows a change in communication capacity according to the number of base stations for each communication scheme.

In FIG. 2, (a) illustrates a change in communication capacity according to the number of base stations in a wireless communication system using a resource division scheme such as a time division multiple access (TDMA) / frequency division scheme (FDMA). (B) shows a change in communication capacity according to the number of base stations in a wireless communication system using a multi-hop method, and (c) shows a change in communication capacity according to the number of base stations in a wireless communication system using a cooperative communication method. Indicates a change in communication capacity.

As shown in Fig. 2, the resource division scheme of (a) simply divides and utilizes limited communication capacity, so that the change in communication capacity does not occur even if the number of base stations that are communication nodes nd is increased. On the other hand, in the multi-hop wireless communication system of (b), since the base stations, which are communication nodes nd, relay transmission data, the communication capacity increases to (nd) ^1/2 according to the number of base stations. That is, as the number of base stations increases, the communication capacity initially increases rapidly, but when the number exceeds the predetermined number, the increase of the communication capacity decreases and the increase rate of the communication capacity decreases significantly compared to the increase rate of the number of base stations. However, in the wireless communication system applying the cooperative communication method of (c), the communication capacity increases linearly in proportion to the number of base stations as a plurality of base stations communicate with each other and transmit data separately. do. However, (c) assumes that the communication capacities of each of the plurality of base stations are the same. In the case of performing communication, interference may occur to cause a decrease in communication capacity.

Since the wireless communication system of the present invention uses a cooperative communication method, as the number of users increases, the number of base stations such as BBS increases, thereby increasing communication capacity to overcome communication obstacles. In particular, in the present invention, since the base station is implemented as a semi-mobile base station using a wireless backhaul, it is very easy to increase the number of base stations.

3 shows a change in communication capacity through cooperative communication of a semi-mobile base station.

Unlike the base station, the number of antennas of the mobile communication terminal to be provided with the wireless communication service is limited to the number of antennas that can be provided with emphasis on portability. In general, a mobile communication terminal is usually provided with only one antenna.

In this case, even if the number of antennas of a base station providing a wireless communication service to the mobile communication terminal is large, the communication capacity by MISO (Multiple Input Single Output) using a plurality of base station antennas and one mobile communication antenna is shown in FIG. Likewise, it does not increase significantly in comparison with the communication capacity by SISO (Single Input Single Output). In other words, even if the number of antennas of the base station is increased, the effect of increasing the communication capacity is not significant. In FIG. 3, the MISO shows a case in which 10 antennas are provided in a base station, whereas only one antenna is provided in a mobile communication terminal.

On the contrary, even if the base station is provided with 10 antennas and the mobile communication terminal is provided with one antenna, 10 * 10 MIMO performance can be obtained when 10 terminals cooperate or transmit by multi-user beamforming, as shown in FIG. As can be seen, a communication capacity gain of approximately four times higher than MISO can be achieved in the region of 25bps / Hz.

4 shows an example of a BANET as an example of the operation of the wireless communication system of the present invention.

The existing network in the building is mainly composed of a wired backhaul, and most of the locations in the building provide communication services by wire. Recently, however, the number of mobile communication terminals performing wireless communication has increased, and the use of wireless communication in buildings has increased due to the reduction of the cost of rebuilding wired networks due to the mobility of users in the building.

In this case, as shown in (a), a conventional wireless communication system that distributes communication capacity of a base station to a building using a pico cell, a femto cell, or a WLAN wireless access point (AP) There is a problem that many mobile communication terminals are concentrated in a building and it is difficult to provide a smooth communication service. In addition, in the case of buildings, since the NLoS environment is mainly formed by the inner wall and the outer wall of the building, there is a limit in that sufficient communication capacity cannot be provided by the mobile communication terminal.

In contrast, the wireless communication system of the present invention shown in (b) is a BBS disposed at a location where LoS is secured from the access antenna AA, and a fixed base station has a first frequency of 5 GHz to 10 THz band or an ultra high frequency of visible light band. Provides a high capacity backhaul using a band, performs cooperative communication using a second frequency band between BBSs, or utilizes a first frequency band, and uses an ultrahigh frequency of the first frequency band again between a BBS and a mobile communication terminal. By performing communication by maximizing the communication capacity from the access antenna (AA) connected to the wired or wireless backbone network to the mobile communication terminal.

That is, between the BBS at a distance from which the LoS is secured from the access antenna AA and the access antenna AA, and between the BBS and the mobile communication terminal, using the ultrahigh frequency of the first frequency band (average frequency efficiency) * (bandwidth) = 5bps / Hz * 200MHz = 1Gbps Communication is performed, and LoS is secured between BBSs between a plurality of BBSs. If communication is performed with communication capacity of 1Gbps, and LoS is not secured between BBSs, massive MIMO communication is performed so that (average frequency efficiency) * (bandwidth) * (number of cooperative antenna groups) = 5bps / Hz * 20MHz * 10 = Communicate with 1Gbps communication capacity.

Therefore, a mobile communication terminal of any location in the building can be provided with a stable communication service by a plurality of BBS. In addition, when stable communication is not provided, it is easy to move a pre-installed BBS or additionally install a new BBS due to the characteristics of the BBS, and actively cope with changes in the communication environment.

Although not shown, the wireless communication system of the present invention maximizes communication efficiency by applying a beam forming technique using a plurality of antennas when communicating using the ultra high frequency of the first frequency band.

5 illustrates a method for providing a wireless communication service using a semi-mobile base station according to an embodiment of the present invention.

Referring to FIG. 5, a method of providing a wireless communication service using a semi-mobile base station of the present invention, first, an access antenna AA connected to a wired / wireless backbone network may include a BBS having LoS secured among a plurality of BBSs AP1 to AP4. In FIG. 5, AP1) is determined (S10). Accordingly, the access antenna AA beamforms the BBS AP1 having the LoS to perform communication using the ultrahigh frequency of the first frequency band (S20).

In addition, the BBS (AP1) communicating with the access antenna (AA) using the first frequency band determines whether or not LoS / NLoS between other BBSs (AP2 to AP4) is provided to provide a communication service to the mobile communication terminal (MS). Determine (S30).

As a result of the determination, if there is the BBS (AP2) having the LoS secured, communication is performed using the BBS (AP2) having the LoS secured using the ultrahigh frequency of the first frequency band (S40). If there are quasi-mobile base stations AP3 and AP4, which are NLoS, giant MIMO communication using a second frequency band is performed for BBSs AP3 and AP4, which are NLoS. At this time, the BBS (AP2) where the LoS secured the LoS is able to perform the massive MIMO communication with the BBS (AP1), and the BBS (AP3) is also the massive MIMO communication with the BBS (AP1, AP2). Can be done.

The BBS AP4 having the LoS secured with the mobile communication terminal MS performs ultra-high frequency communication of the first frequency band with the mobile communication terminal MS using a beamforming technique.

Here, since the BBS (AP4) performs ultra-high frequency communication with the mobile communication terminal (MS) by using a beamforming technique, the mobile communication terminal (MS) can be provided with a communication capacity of 1 Gbps even without a plurality of antennas. . That is, a large communication capacity may be serviced regardless of the number of antennas, which is a limitation of the mobile communication terminal (MS).

The method according to the invention can be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of the recording medium include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, and the like, and also include a carrier wave (for example, transmission through the Internet). The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible.

Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (3)

At least one quasi-mobile communication terminal receiving a wireless communication service;
At least one fixed base station connected to at least one of a wired and wireless backbone network and having a plurality of antennas for performing wireless communication using an ultrahigh frequency of a first frequency band; And
And a plurality of quasi-mobile base stations each having a plurality of antennas, performing wireless communication with the at least one mobile communication terminal and the at least one fixed base station using the ultra-high frequency, and being movable;
Performing wireless communication using the ultra-high frequency using a beamforming technique for a quasi-mobile base station having LoS secured among the plurality of quasi-mobile base stations,
When LoS is not secured among the plurality of quasi-mobile base stations, a massive MIMO communication is performed in a cooperative communication manner by using a second frequency band having a lower frequency band than the first frequency band. delete According to claim 1,
The plurality of semi-mobile base station,
Wireless communication system, characterized in that installed in the building.

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