JP7353152B2 - High frequency antenna unit and wireless communication unit using the same - Google Patents

Description

The present invention relates to a high frequency antenna unit in which a plurality of transmitting and receiving antenna groups are installed together, and a wireless communication unit using the same.

Patent Document 1 discloses that in wireless communication between a mobile terminal and a base radio station, in order to improve the communication situation in areas where radio wave transmission is likely to be blocked by obstacles such as mountains and hills intervening, the same communication band is used. A wireless communication unit is disclosed in which a plurality of relay devices (transmitting/receiving devices) are set up in close proximity to each other. This type of communication device has a problem in that a transmission wave from one relay device is looped around and received by another communication device that communicates on a nearby channel, resulting in interference waves.

In Patent Document 1, in order to solve this problem, an anti-phase waveform of a transmission wave that is expected to receive wraparound is generated between the transmitting antenna of one relay device and the receiving antenna of the other relay device. Proposals have been made to provide a canceller circuit that performs cancellation by inputting the signal into the receiving circuit of the other relay device.

Japanese Unexamined Patent Publication No. 189034/1983

However, when it comes to suppressing interference waves from adjacent channels, the structure of the antenna used for transmission and reception is also an important point. For example, when a wireless communication unit is mounted on a mobile object such as a ship, the obstacle situation around the wireless communication unit changes every moment depending on the position of the mobile object, and it is difficult to take effective measures to suppress interference waves using normal methods. In many cases, this is not possible.

However, regarding the structure of the transmitting/receiving antenna group for a wireless communication unit equipped with multiple systems of transmitting/receiving devices with close channels, there is no information on what structure is effective in suppressing wraparound interference waves, including Patent Document 1. It is difficult to say that sufficient consideration has been made to date.

An object of the present invention is to provide a high-frequency antenna unit that can effectively suppress transmission waves output from one of multiple transmitting/receiving devices installed in the same wireless communication unit from being received as interference waves by other transmitting/receiving devices. and to provide a wireless communication unit using the same.

In order to solve the above problems, a high frequency antenna unit of the present invention includes a plurality of high frequency antennas and a support frame body to which the high frequency antennas are attached, and each of the multiple high frequency antennas is connected to the same transmitting/receiving device. It includes a plurality of transmitting and receiving antenna groups consisting of transmitting antennas and receiving antennas, and the plurality of transmitting and receiving antenna groups are fixedly attached to the support frame at predetermined intervals in a predetermined arrangement direction, and each has a different transmitting and receiving antenna group. The support frame includes a plurality of antenna support plates arranged at predetermined intervals in the arrangement direction and each having a plate surface whose normal direction is the arrangement direction. The transmitting antennas and receiving antennas constituting a group are distributed and attached to a plurality of antenna support plates, and the high frequency antennas attached to a pair of antenna support plates adjacent to each other in the arrangement direction are The distance between the feeding points is set to be equal to or more than 1/2 wavelength of the transmitted and received waves.

Further, the wireless communication unit of the present invention is a wireless communication unit configured to be mounted on a mobile body and for performing wireless network communication with a mobile terminal, and the wireless communication unit is configured to be able to be mounted on a mobile body, and is a wireless communication unit for performing wireless network communication with a mobile terminal. a connectable wireless base station section, an EPC (Evolved Packet Core) functional section that is wired connected to the wireless base station section and functions as an upper network control section for the wireless base station section; Relay wireless communication connectable via the radio base station section of the upstream unit (hereinafter referred to as the upstream radio base station section), which is another radio communication unit, and the upstream inter-unit radio bearer (hereinafter referred to as the upstream inter-unit radio bearer). The radio base station section includes a relay radio communication section of a downstream unit (hereinafter referred to as a downstream relay radio communication section), which is a second separate radio communication unit, and a downstream inter-unit radio bearer (hereinafter referred to as a downstream unit). The wireless unit includes a wireless unit main body that can be connected via an intermediary radio bearer, a plurality of high-frequency antennas, and a support frame to which the high-frequency antennas are attached, and the multiple high-frequency antennas are connected to a relay wireless communication section. a first transmitting/receiving antenna group consisting of a transmitting antenna and a receiving antenna, and a second transmitting/receiving antenna group consisting of a transmitting antenna and a receiving antenna connected to the wireless base station section, and the plurality of transmitting/receiving antenna groups are connected to the support frame. They are fixedly attached to the body at predetermined intervals in a predetermined array direction, and are planned to be connected to different transmitting and receiving devices, and the support frames are arranged at predetermined intervals in the array direction. The transmitting antenna and the receiving antenna constituting the transmitting/receiving antenna group are distributed and attached to the plurality of antenna supporting plates, and the above-mentioned A high-frequency antenna unit in which high-frequency antennas are attached to a pair of antenna support plates adjacent to each other in the arrangement direction, and the distance between the feeding points of the high-frequency antennas in the arrangement direction is determined to be 1/2 wavelength or more of the transmitted and received waves. It is characterized by having the following.

In the high frequency antenna unit of the present invention, the transmitting antenna and the receiving antenna constituting the same transmitting and receiving antenna group are mounted on the first main surface of the corresponding antenna support plate at a predetermined distance of at least 1/4 wavelength of the transmitted and received waves. The antennas can be attached with a spacing between the antennas. In addition, the antenna support plate can be formed with a plurality of insertion holes distributed at predetermined intervals, which are position change units, into which the above-mentioned fastening members can be attached. While positioning the mounting plate, the fastening member can be mounted by selecting one of the plurality of insertion holes at a position corresponding to the antenna support plate.

On the other hand, antenna support plates may be provided in a form that individually corresponds to the transmitting antennas and receiving antennas included in a plurality of transmitting/receiving antenna groups, and the transmitting antennas and It is also possible to configure one of the receiving antennas to be fixed.

In the high frequency antenna unit of the present invention, the support frame has a metal plate having a plate surface whose normal direction is the arrangement direction at a position separating two transmitting and receiving antenna groups arranged adjacent to each other in the arrangement direction. A shielding plate can be provided. In this case, at least some of the plurality of antenna support plates can be made of metal and can be configured to also serve as a metal shielding plate.

The high frequency antenna may include a metal base and a metal antenna element attached to the metal base, and may be fixed to a metal shielding plate through the metal base in an electrically conductive manner.

The metal base has a metal mounting plate for attaching the metal base to a metal shielding plate, and the antenna element is attached to a first major surface of the metal mounting plate, while the metal mounting plate has a metal shielding plate on a second major surface. It can be configured such that it is attached in close contact with the first main surface of the plate. Further, a configuration may be provided in which a fastening member is provided to penetrate the metal mounting plate and the metal shielding plate and fasten the metal mounting plate and the metal shielding plate in close contact.

According to the configuration of the high frequency antenna unit of the present invention, the transmitting/receiving antenna group consisting of the transmitting antenna and the receiving antenna, each connected to the same transmitting/receiving device, is fixed at a predetermined interval in a predetermined arrangement direction with respect to the support frame. can be attached to. The distance between the feed points of the high-frequency antennas attached to a pair of antenna support plates adjacent to each other in the arrangement direction is ensured to be at least 1/2 wavelength of the transmitted and received waves. It is possible to improve the isolation between the transmitting antenna and the receiving antenna between the two transmitting and receiving antenna groups. Thereby, it is possible to effectively suppress a problem in which a transmission wave from one transmitting/receiving antenna group is received by the receiving antenna of the other transmitting/receiving antenna group as an interference wave.

The wireless communication unit of the present invention using this has a relay wireless communication section and a wireless base station section as a plurality of transmitting/receiving devices, and each uses an upstream unit-to-unit radio bearer and a downstream unit-to-unit radio bearer to perform other radio communications. Since it can be wirelessly connected to other units, it is possible to build a more expansive wireless network system. By incorporating the first transmitting/receiving antenna group for constructing the upstream inter-unit radio bearer and the second transmitting/receiving antenna group for constructing the downstream inter-unit radio bearer into the high frequency antenna unit of the present invention, , it is possible to effectively suppress loop reception of transmitted waves between the relay radio communication unit and the radio base station unit.

FIG. 1 is a schematic diagram showing the concept of a constituent unit of a wireless network system constructed using a wireless communication unit of the present invention. FIG. 2 is a block diagram schematically showing the electrical configuration of the structural unit in FIG. 1. FIG. FIG. 2 is a block diagram showing an example of the electrical configuration of a wireless communication unit of the present invention. FIG. 2 is a diagram conceptually showing a 3GPP control plane protocol stack. FIG. 2 is a diagram conceptually showing a 3GPP user plane protocol stack. FIG. 3 is a diagram conceptually showing 3GPP downlink channel mapping. FIG. 4 is a diagram conceptually showing uplink channel mapping. FIG. 3 is a conceptual diagram showing the relationship between frequency band channels and resource blocks. FIG. 1 is a diagram schematically showing an example of a configuration of a wireless network system. FIG. 3 is a communication flow diagram showing an attach sequence of a relay wireless communication unit of a wireless communication unit to another upstream wireless communication unit. FIG. 2 is a communication flow diagram showing an attach sequence of a UE (mobile terminal) to a wireless communication unit. FIG. 2 is a plan view showing a configuration example of a high frequency antenna. 13 is an AA sectional view and a BB sectional view of the high frequency antenna in FIG. 12. 14 is a front view showing an embodiment of the high frequency antenna unit of the present invention using the high frequency antenna of FIGS. 12 and 13. FIG. FIG. 15 is a plan view of the high frequency antenna unit of FIG. 14. 14 is a chart showing radiation characteristics of the high frequency antenna shown in FIGS. 12 and 13. FIG. FIG. 15 is a schematic diagram showing the arrangement of high-frequency antennas in the high-frequency antenna unit of FIG. 14 together with the radiation characteristic shape of each antenna. 15 is a plan view showing a modification of the high-frequency antenna unit of FIG. 14 in which high-frequency antennas attached to a pair of vertically adjacent antenna support plates are arranged in a positional relationship in which the null points do not coincide with each other; FIG. 15 is a front view showing a modified example in which the vertical distance of the high frequency antennas attached to a pair of vertically adjacent antenna support plates is reduced in the high frequency antenna unit of FIG. 14. FIG. 15 is a plan view showing a first modification example in which a pair of high-frequency antennas are arranged diagonally on the antenna support plate in the high-frequency antenna unit of FIG. 14. FIG. 15 is a plan view showing a second modification example in which a pair of high frequency antennas are arranged diagonally on the antenna support plate in the high frequency antenna unit of FIG. 14. FIG. FIG. 2 is a front view showing an embodiment of a high frequency antenna unit in which an antenna support plate is formed of an insulating material. FIG. 23 is a plan view of the high frequency antenna unit of FIG. 22. FIG. 3 is a front view showing an example of a high-frequency antenna unit in which high-frequency antennas included in a plurality of transmitting/receiving antenna groups are attached to individual antenna support plates and arranged vertically. 4 is a diagram showing the correspondence between each high frequency antenna included in the high frequency antenna unit in FIG. 24 and each antenna included in the wireless communication unit in FIG. 3, together with a modification example. FIG. 25 is a diagram showing a first modification of the high frequency antenna unit of FIG. 24. FIG. 25 is a diagram showing a second modification of the high frequency antenna unit of FIG. 24. FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described based on the accompanying drawings.
FIG. 1 is a schematic diagram showing the concept of constructing a pair of wireless communication units, which are the constituent units of a wireless network system, using the wireless communication unit of the present invention. The wireless communication unit pair consists of wireless communication units 1 (A) and 1 (B) having the same configuration, which is an embodiment of the present invention (hereinafter also referred to as wireless communication unit pair 1 (A), 1 (B)), Each device performs wireless communication with the UE (mobile terminal) 5 according to a communication protocol stack of a method defined by 3GPP (in this embodiment, LTE is used, but other methods such as WiMAX may be used). It is configured as.

The wireless communication units 1(A) and 1(B) are installed in large ships WS(A) and WS(B), which are moving bodies, respectively, and are wirelessly connected by an inter-unit radio bearer 55, which will be described in detail later. Each radio communication unit 1(A), 1(B) forms a cell 50(A), 50(B) to which a UE (mobile terminal) 5 can connect, respectively. In addition, small vessels FB (for example, fishing boats, tugboats, etc.) are operating around large vessels WS (A) and WS (B) (for example, fishing mother ships, tankers, etc.), and cell 50 (A) or cell 50 The crew of the small boat FB in (B) is carrying UE5. These UEs 5 are wirelessly connected to the nearest wireless communication units 1 (A) and 1 (B) by a terminal radio bearer 57, respectively. Note that the UE 5 may be carried by the crew members of the large ships WS (A) and WS (B). Further, the wireless communication units 1(A) and 1(B) may be installed in a moving body (such as a vehicle) other than a ship, or may be fixedly installed at a desired installation location on land, for example.

FIG. 2 shows a functional block configuration of wireless communication units 1(A) and 1(B). Wireless communication units 1(A) and 1(B) have the same electrical configuration. In this specification, when a plurality of wireless communication units and their components are shown to be distinguished from each other, the same number is given to the corresponding components, and a capital letter in parentheses is given following the number. Shown. On the other hand, when indicating each component without distinguishing between wireless communication units, the capital letters in parentheses may be omitted. Hereinafter, the description will mainly be made using the symbols on the side of the wireless communication unit 1 (A), but the description on the side of the wireless communication unit 1 (B) will also be made using the corresponding symbols as necessary.

The radio communication unit 1 (A) includes a radio base station section 4 (A) (eNodeB (evolved NodeB)) to which a UE (mobile terminal) 5 can connect via a terminal radio bearer 57, and a radio base station section 4 (A). The EPC (Evolved Packet Core) function section 3 (A) is connected by wire to the wireless base station section 4 (A) and functions as an upper network control section for the wireless base station section 4 (A). The EPC function section 3 (A) also has an upstream inter-unit radio bearer for the radio base station section 4 (B) (upstream radio base station section) of the upstream radio communication unit 1 (B) (upstream unit). A relay wireless communication section 9 (A) connectable via a wireless bearer 55 (upstream unit-to-unit wireless bearer) is connected by wire.

On the other hand, the wireless communication unit 1 (B) is connected by wire to a similar wireless base station section 4 (B) and the wireless base station section 4 (B), and functions as an upper network control section for the wireless base station section 4 (B). It includes an EPC function section 3 (B) and a relay wireless communication section 9 (B) connected by wire to the EPC function section 3 (B). If another radio communication unit is arranged upstream of the radio communication unit 1 (B), the relay radio communication unit 9 (B) transmits an inter-unit radio bearer to the radio base station of that radio communication unit. (See FIG. 9). In addition, the wireless base station section 4 (B) transmits the downstream inter-unit wireless communication to the relay wireless communication section 9 (A) (downstream relay wireless communication section) of the downstream wireless communication unit 1 (A) (downstream unit). Connection is possible via a bearer 55 (downstream inter-unit radio bearer). That is, the inter-unit radio bearer 55 becomes an upstream inter-unit radio bearer when viewed from the radio communication unit 1 (A), and becomes a downstream inter-unit radio bearer when seen from the radio communication unit 1 (B). The inter-unit radio bearer 55 (downstream inter-unit radio bearer and upstream inter-unit radio bearer) has the same radio protocol stack as the terminal radio bearer 57, and in this embodiment, both are constructed according to the LTE radio protocol stack. Ru.

Next, in both wireless communication units 1(A) and 1(B) (hereinafter collectively referred to as wireless communication unit 1), the EPC function unit 3 is connected to an MME (Mobility Management Entity) 2, an S-GW (Serving Gateway) 6 serving as a gateway on the user plane side, an EPC function unit 3, and upstream network elements of the EPC function unit 3 (here, a router 8 (described later) and a relay wireless communication unit 9), and has a P-GW (PDN (Packet Data Network) Gateway) 7 that manages IP addresses for the upstream network element side (that is, the upstream unit side). Further, a plurality of UEs 5 are wirelessly connected to the radio base station section 4 via a terminal radio bearer 57.

On the control plane side, the radio base station unit (eNodeB) 4 is connected to the MME 2 via the S1-MME interface. Furthermore, on the user plane side, the wireless base station section 4 is connected to the S-GW 6 via the S1-U interface. Further, the S-GW 6 is connected to the P-GW 7 via the S5 interface.

FIG. 3 is a block diagram showing the electrical configuration of the wireless communication unit 1. The EPC function unit 3 is mainly composed of microcomputer hardware, including a CPU 301, a RAM 302 serving as a program execution area, and a mask ROM 303 (stores firmware for microcomputer hardware peripheral control that does not require permanent rewriting); (the same applies hereinafter) and a bus 306 that interconnects them. Further, a flash memory 305 is connected to the bus 306, and communication firmware 305a including an LTE protocol stack for EPC is stored therein, and each of the MME2, S-GW6, and P-GW7 in FIG. 2 uses the LTE protocol stack as a platform. Programs for an MME entity 305b, an S-GW entity 305c, and a P-GW entity 305d, which virtually implement functions, are installed.

Further, an upstream communication interface 304A and a downstream communication interface 304B are connected to the bus 306. An input/output port for IP packets for P-GW is secured in the upstream communication interface 304A, and an input/output port for IP packets for S-GW is secured in the downstream communication interface 304B. In the above configuration, the MME 2, S-GW 6, and P-GW 7 in FIG. 2 are configured as virtual functional blocks on computer hardware, but each may be configured using independent hardware logic.

The relay wireless communication unit 9 is mainly composed of microcomputer hardware, and includes a CPU 901, a RAM 902 serving as a program execution area, a mask ROM 903, a bus 906 that interconnects them, and the like. A flash memory 905 is connected to the bus 906, and communication firmware 905a including an LTE protocol stack for the relay wireless communication unit is stored therein. Further, a wireless communication section 912 and a communication interface 904 are connected to the bus 906 for wirelessly connecting to an upstream wireless base station section by constructing an inter-unit radio bearer. The communication interface 904 is connected to the upstream communication interface 304A of the EPC function unit 3 via the wired communication bus 30.

The wireless base station unit 4 is mainly composed of microcomputer hardware, and includes a CPU 401, a RAM 402 serving as a program execution area, a mask ROM 403, a bus 406 that interconnects them, and the like. A flash memory 405 is connected to the bus 406, and communication firmware 405a including an LTE protocol stack for wireless base stations is stored therein. Further, a wireless communication unit 412 and a communication interface 404 are connected to the bus 406 for wirelessly connecting to the UE by constructing a terminal radio bearer. The communication interface 404 is connected to the downstream communication interface 304B of the EPC function section 3 via the wired communication bus 31.

In the relay wireless communication unit 9, the LTE protocol stack for the relay wireless communication unit incorporated in the communication firmware 905a is the same as the protocol stack for the UE (mobile terminal) described later. In other words, the procedure for connecting the relay radio communication unit 9 to the upstream radio base station is the same as the attach sequence, which is the procedure for connecting a UE (mobile terminal). Further, a router 8 that relays transmission and reception of IP packets between the EPC function unit 3 and an external network 60 such as the Internet is connected to the communication bus 30 (that is, a router 8 is connected to the EPC function unit 3 and an external network 60 such as the Internet). (A router 8 is provided between the two.)

Next, the wireless communication unit 912 of the relay wireless communication unit 9 is provided with an antenna connector 907CN, which is connected to a first transmitting/receiving antenna group (consisting of a transmitting/receiving antenna 907TR and a receiving antenna 907R; hereinafter, the first transmitting/receiving antenna group 907TR). , 907R) are connected via an antenna cable ACV (FIG. 15: for example, a coaxial cable). The transmitting/receiving antennas 907TR of the first transmitting/receiving antenna group 907TR, 907R function as both a transmitting antenna and a receiving antenna by switching. Furthermore, when the transmitting/receiving antenna 907TR functions as a receiving antenna, the receiving antenna 907R forms receiving diversity with it. On the other hand, the wireless communication section 412 of the wireless base station section 4 is provided with an antenna connector 407CN, which is connected to a second transmitting/receiving antenna group (transmitting/receiving antenna 407TR and receiving antenna 407R) having the same configuration as the first transmitting/receiving antenna group 907TR, 907R. (hereinafter also referred to as second transmitting/receiving antenna group 407TR, 407R) are connected via antenna cable ACV. The portion of the wireless communication unit 1 excluding the first transmitting/receiving antenna group 907TR, 907R and the second transmitting/receiving antenna group 407TR, 407R constitutes a unit main body. Furthermore, each of the antennas included in the transmitting/receiving antenna group described above is configured as a high frequency antenna having the same structure as will be explained later with reference to FIGS. 12 and 13, and when these antennas are collectively referred to, they are also referred to as "high frequency antenna 200."

The first transmitting/receiving antenna group 907TR, 907R and the second transmitting/receiving antenna group 407TR, 407R (that is, a plurality of transmitting/receiving antenna groups) are the high frequency antenna unit 250, which is an embodiment of the present invention, shown in FIGS. 14 and 15. form. The high frequency antenna unit 250 includes a support frame 251 to which a plurality of high frequency antennas 200 are attached. The support frame body 251 has a plurality of antennas arranged at predetermined intervals in a predetermined arrangement direction AD (in this embodiment, it is a vertical direction, but for example, it may be in a direction inclined with respect to a horizontal plane). Support plates 252 (A) and 252 (B) (hereinafter, when these are collectively referred to, they are also simply referred to as "antenna support plates 252") are provided. The antenna support plate 252 has a plate surface (main surface) whose normal direction is the arrangement direction AD. In this embodiment, the plurality of antenna support plates 252 have a rectangular planar shape, and four corners are supported by metal (for example, aluminum or aluminum alloy) supports 253 so that each plate surface is horizontal. ing. Each high frequency antenna is fixed to the first main surface (upper surface) of antenna support plate 252. Note that an installation base 254 is attached to the lower end of each support column 253.

In the high frequency antenna unit 250 of FIG. 14, all the antenna support plates 252(A) and 252(B) are made of metal, for example, aluminum or aluminum alloy plates with a thickness of about 2 mm to 5 mm, and the upper antenna support A first transmitting/receiving antenna group 907TR, 907R is attached to the upper surface of the plate 252(A), and a second transmitting/receiving antenna group 407TR, 407R is attached to the upper surface of the lower antenna support plate 252(B). Note that the upper antenna support plate 252(A) is also used as a metal shielding plate that partitions the first transmitting/receiving antenna group 907TR, 907R and the second transmitting/receiving antenna group 407TR, 407R adjacent to each other in the arrangement direction AD. There is.

As shown in FIG. 13, the high frequency antenna 200 is fixed to an antenna support plate 252 (A) (metal shielding plate) by a metal base 200B in an electrically conductive manner. This increases the volume of the ground metal that is electrically connected to the high-frequency antenna 200, making it possible to stabilize the ground potential. Further, the metal base 200B has a metal mounting plate 201 (for example, made of aluminum or aluminum alloy) for attaching to a metal shielding plate, and an antenna element 203 is attached to the first main surface of the metal mounting plate 201. Furthermore, the metal mounting plate 201 is attached with its second main surface in close contact with the first main surface of the metal shielding plate.

Further, the metal base 200B includes an antenna feed plate 202 whose plate surface is arranged parallel to the antenna support plate 252. The antenna element 203 is formed into a rod shape that protrudes from the antenna feed plate 202 so that the first end serving as the antenna feed point is connected to the first main surface of the antenna feed plate 202 and the second end is a free end. , the entire antenna is configured as an omnidirectional antenna. Even when the high-frequency antenna unit 250 is mounted on a moving object such as a ship WS as shown in FIG. 1, each high-frequency antenna 200 included therein can be made into an omnidirectional antenna, so that the antenna can be The radio wave transmission and reception characteristics of the wireless communication unit 1 can be ensured uniformly in each direction. As shown in FIG. 14, the protruding height AH (antenna length) of the antenna element 203 from the antenna feed plate 202 is set to about λ/4, where λ is the wavelength of the transmitted and received waves. In this embodiment, the 700 MHz band is used as described later, and the protrusion height AH is about 10 to 11 cm.

In FIG. 13, a high frequency antenna 200 includes an antenna feed plate 202 and a metal mounting plate 201 that are constructed as separate members. Specifically, the antenna feed plate 202 is fixed above the metal mounting plate 201 at a predetermined interval via spacer bolts 205. As shown in FIG. 12, a plurality of spacer bolts 205 are provided around the antenna element 203 at predetermined angular intervals. Further, as shown in FIG. 13, the legs of each spacer bolt 205 protrude below the antenna feed plate 202, and the lower ends thereof are screwed into screw holes on the metal mounting plate 201 side, and nuts are screwed into the upper ends of the legs. 207 is brought into close contact with the lower surface of the metal mounting plate 201 to prevent loosening.

Further, a threaded portion 203t is formed on the lower end side of the antenna element 203. The threaded portion 203t passes through the antenna power feeding plate 202 in the thickness direction and protrudes to the lower surface side thereof, and an elbow-shaped terminal fitting 204 is attached to this with a nut 203n. The antenna feed plate 202 and the lower end side of the antenna element 203 are covered with a resin cover 209, and the terminal fittings 204 are exposed in a notch 209i formed in the wall of the cover 209. Further, a connector ACN of an antenna cable ACV is detachably attached to the terminal fitting 204. Note that the antenna feed plate 202 can also be used as a metal mounting plate. In this case, the power feeding terminal to the antenna element 203 can be formed on the outer peripheral surface of the antenna power feeding plate 202.

The metal mounting plate 201 and antenna support plate 252 (A) (metal shielding plate) of the high-frequency antenna 200 are tightly fastened together by a fastening member 255 that penetrates them. If it is desired to permanently fasten the two, the fastening member 255 can be made of a rivet, but in this embodiment, the fastening member 255 is made of a screw member and is detachable from the antenna support plate 252. Specifically, as shown in FIG. 13, a fastening member 255 made of a countersunk screw is inserted from the bottom side into a through hole 252h formed in the antenna support plate 252, and its legs are connected to the metal mounting plate. It is screwed into a screw hole formed in 201. As shown in FIG. 12, a plurality of fastening members 255 are provided around the axis of the antenna element 203 at predetermined angular intervals. Note that a conductive paste layer 208 is formed between the lower surface of the metal mounting plate 201 and the upper surface of the antenna support plate 252 to reduce contact resistance therebetween.

Further, as shown in FIGS. 14 and 15, the first transmitting/receiving antenna group 907TR, 907R connected to the relay wireless communication section 9 in FIG. ), second transmitting/receiving antenna groups 407TR and 407R, which are also connected to the wireless base station section 4, are respectively attached to the first main surface (upper surface) of the lower antenna support plate 252(B). That is, the transmitting antenna and the receiving antenna that constitute the same transmitting and receiving antenna group are mounted on the first main surface of the corresponding antenna support plate.

Next, between the high frequency antenna 907TR and the high frequency antenna 407TR attached to a pair of antenna support plates 252(A) and 252(B) adjacent to each other in the arrangement direction AD (vertical direction), and between the high frequency antenna 907R and the high frequency antenna A distance DV between feeding points of the high-frequency antennas 200 in the arrangement direction AD is secured between the antenna 407R and the antenna 407R by 1/2λ or more (approximately 2λ in FIG. 14). Further, high frequency antennas 907TR, 907R and 407TR, 407R on each antenna support plate 252(A), 252(B) are arranged at a predetermined antenna interval DH( In FIG. 14, it is attached at about (3/2)λ).

In other words, the horizontal distance between the high-frequency antennas forming the transmitting and receiving antenna groups on the same antenna support plate is 1/4λ or more, with the arrangement direction AD being the vertical direction, and the first transmitting and receiving antenna group is distributed to vertically adjacent antenna support plates. And the vertical distance between the high frequency antennas of the second transmitting and receiving antenna group (907TR and 907R, and 407TR and 407R) is ensured to be 1/2λ or more. This further increases the isolation between the transmitting and receiving antennas of the first transmitting/receiving antenna group 907TR, 907R and the second transmitting/receiving antenna group 407TR, 407R.

As shown in FIG. 15, a pair of a transmitting/receiving antenna 907TR and a receiving antenna 907R forming a first transmitting/receiving antenna group is arranged at the center of the plate surface of the antenna support plate 252(A). Further, a pair of a transmitting/receiving antenna 407TR and a receiving antenna 407R forming the second transmitting/receiving antenna group is arranged at the center of the plate surface of the antenna support plate 252(B). Then, the transmitting/receiving antenna 907TR on the antenna support plate 252(A) and the transmitting/receiving antenna 407TR on the antenna support plate 252(B), and the receiving antenna 907R and the receiving antenna 407R are arranged in the antenna array on the antenna support plate. They are attached to the same side in each direction.

FIG. 16 shows the radiation characteristics of the high frequency antenna used in this embodiment at a frequency of around 750 MHz. The high-frequency antenna is a commercially available product (MA-WO-UWB, manufactured by MARS ANTENNA, Israel), and has a z-axis direction in the axial direction of the antenna element 203 and an x-axis direction in a direction independently orthogonal to the z-axis direction. When the axis and the y-axis are determined, the directivity around the z-axis (the axis of the antenna element) is almost completely isotropic, as shown at the bottom of FIG. On the other hand, in the directionality in the plane (vertical plane) including the z-axis shown in the upper part of FIG. 16, the upward radiation intensity is slightly higher than the downward radiation intensity with respect to the horizontal plane (xy plane). . As a feature of the radiation characteristics of the omnidirectional antenna, in the directivity in a plane including the z-axis, a point where the radiation characteristics are minimized around the tip of the antenna element, that is, a null point occurs.

As shown in FIG. 17, the transmitting/receiving antenna 907TR and the transmitting/receiving antenna 407TR, and the receiving antenna 907R and the receiving antenna 407R are in a positional relationship such that the null points NP in the antenna radiation characteristics overlap each other when projected onto the xy plane. each is placed. In other words, in a pair of adjacent antenna support plates 252(A) and 252(B), the transmitting antennas (907TR, 407TR) and receiving antennas (907R, 407R) belonging to different transmitting/receiving antenna groups are null in plan view. The points NP are arranged so that they overlap each other. Note that "the null points overlap each other" means that the distance between the null point positions of each antenna projected on the xy plane is within 5% of the transmitting and receiving wavelength.

Furthermore, as shown in FIG. 15, the high-frequency antennas 907TR, 907R, 407TR, and 407R on the antenna support plates 252(A) and 252(B) configured as metal plates further suppress the aforementioned loop interference waves. From this point of view, it is desirable that the shortest margin distances Mx (x direction) and My (y direction) from the antenna element 203 to the support plate edge are secured to, for example, λ/6 or more. For example, in FIG. 15, Mx is set to λ/4 and My is set to approximately (3/4)λ. The antenna cable ACN connected to each high frequency antenna 907TR, 907R, 407TR, 407R is routed on the antenna support plates 252(A), 252(B), and the terminal antenna connector ACN is connected to the outside of the support frame 251. It is taken out.

Furthermore, a plurality of through holes 252h into which fastening members 255 (FIG. 13) can be attached are formed in the antenna support plate 252 in a distributed manner at predetermined intervals d, which are units of position change. The metal mounting plate 201 in FIG. 13 is a fastening member that is positioned at a desired position on the antenna support plate 252 in FIG. 255 can be installed. Thereby, the fixed positions of the high-frequency antennas 907TR, 907R, 407TR, and 407R can be changed and adjusted as appropriate so that the antenna spacing is optimal even when, for example, the wavelength of the transmitted and received waves is changed.

Returning to FIG. 3, the wireless communication unit 1 (unit main body) includes a removable secondary battery module 21 (for example, a lithium ion secondary battery module, a nickel metal hydride secondary battery module, etc.), a wireless base station section 4, an EPC Each of the functional circuit blocks of the functional unit 3, router 8, and relay wireless communication unit 9, and the power supply circuit unit 22 that converts the input voltage from the secondary battery module 21 into a driving voltage of each functional circuit block and outputs the drive voltage are portable. It has a structure that is integrally assembled with the casing 23. As a result, the wireless communication unit 1 can autonomously procure the driving power supply voltage from the secondary battery module 21, and can be used without problems even in installation locations where external power supply voltage such as commercial AC cannot be used (for example, at sea). be. The portable case 23 has a box shape made of metal or reinforced resin, and in the example shown in FIG. 3, casters 24C are provided at the bottom of the portable case 23, and casters 24C are placed on the back side for convenience of transportation or movement. A handle 24 is provided for use.

If the output voltage of the secondary battery module 21 drops due to discharge, remove the secondary battery module 21 from the portable housing 23 and attach it to a dedicated charger connected to a commercial AC power source or private power generator (not shown), for example. It is possible to charge the battery. Further, the power supply circuit section 22 can also receive power from an external power supply voltage such as the above-mentioned commercial alternating current or a centralized power supply section provided in a moving body, and can convert and output the above-mentioned driving power supply voltage.

Furthermore, it is also possible to configure the secondary battery module 21 to be charged using the external power supply voltage. For example, if the power supply circuit section 22 is receiving power from a commercial alternating current or the like and the power reception is interrupted due to a power outage, the operation of the wireless communication unit 1 can be continued by switching to receiving power from the secondary battery module 21. It can also be configured as follows.

4 and 5 show wireless protocol stacks in the LTE system, FIG. 4 shows a user plane protocol stack, and FIG. 5 shows a control plane protocol stack. The wireless protocol stack is divided into layers 1 to 3 of the OSI reference model, with layer 1 being the PHY (physical) layer. Layer 2 includes a MAC (Medium Access Control) layer, an RLC (Radio Link Control) layer, and a PDCP (Packet Data Convergence Protocol) layer. Layer 3 includes an RRC (Radio Resource Control) layer and a NAS (Non-Access Stratum) layer.

The role of each layer is as follows.
- PHY layer: performs encoding/decoding, modulation/demodulation, antenna mapping/demapping, and resource mapping/demapping. Data and control signals are transmitted between the PHY layer of the UE 5 and the relay radio communication unit 9 and the PHY layer of the radio base station unit (eNodeB) 4 via a physical channel.
- MAC layer: Performs data priority control, HARQ retransmission control processing, random access procedures, etc. Data and control signals are transmitted between the MAC layer of the UE 5 and the relay radio communication unit 9 and the MAC layer of the radio base station unit 4 via a transport channel. The MAC layer of the radio base station unit 4 includes a scheduler that determines uplink and downlink transport formats (transport block size, modulation and coding scheme (MCS)) and resource blocks to be allocated to the UE 5.

- RLC layer: transmits data to the RLC layer on the receiving side using the functions of the MAC layer and PHY layer. Data and control signals are transmitted between the RLC layer of the UE 5 and the RLC layer of the radio base station section 4 via logical channels.
- PDCP layer: Performs header compression/decompression, encryption/decryption of PDU.
- RRC layer: Defined only in the control plane that handles control signals. Messages for various settings (RRC messages) are transmitted between the RRC layer of the UE 5 and the RRC layer of the radio base station section 4. The RRC layer controls logical, transport and physical channels according to the establishment, re-establishment and release of radio bearers. If there is a connection (RRC connection) between the RRC of the UE5 and the RRC of the radio base station unit 4, the UE5 is in RRC connected mode, otherwise it is in RRC idle mode.

The above layers are used in both the control plane and the user plane. On the other hand, only the control plane, the UE 5, the relay wireless communication unit 9, and the MME 2 are provided with a NAS layer that performs session management, mobility management, etc. higher than the RRC layer. Further, a user data transmission interface between the radio base station section 4 and the EPC function section 3 side is provided with a GTP-U (GPRS (General Packet Radio Service) Tunneling Protocol for User Plane) layer. The GTP-U layer is for identifying the connection destination UE 5 or relay radio communication unit 9 and identifying the radio bearer to be used.

Next, FIG. 6 shows downlink channel mapping in the LTE system. Here, a mapping relationship between a logical channel (Downlink Logical Channel), a transport channel (Downlink Transport Channel), and a physical channel (Downlink Physical Channel) is shown. Below, they will be explained in order.
- DTCH (Dedicated Traffic Channel) is a dedicated logical channel for data transmission. DTCH is mapped to DLSCH (Downlink Shared Channel), which is a transport channel.

- DCCH (Dedicated Control Channel): A logical channel for transmitting dedicated control information between the UE 5 and the network. DCCH is used when the UE 5 and the relay radio communication unit 9 have an RRC connection with the radio base station unit 4. DCCH is mapped to DLSCH.
- CCCH (Common Control Channel): A logical channel for transmitting control information between the UE 5, the relay radio communication section 9, and the radio base station section 4. CCCH is used when the UE 5 and the relay radio communication unit 9 do not have an RRC connection with the radio base station unit 4. CCCH is mapped to DLSCH.

- BCCH (Broadcast Control Channel): A logical channel for distributing system information. The BCCH is mapped to a BCH (Broadcast Channel) or DLSCH, which is a transport channel.
- PCCH (Paging Control Channel): A logical channel for notifying paging information and system information changes. The PCCH is mapped to a PCH (Paging Channel), which is a transport channel.

Further, the mapping relationship between transport channels and physical channels is as follows.
- DLSCH and PCH: mapped to PDSCH (Physical Downlink Shared Channel). DLSCH supports HARQ, link adaptation, and dynamic resource allocation.
- BCH: Mapped to PBCH (Physical Broadcast Channel).

Next, FIG. 7 shows uplink channel mapping in the LTE system. Similar to FIG. 6, the mapping relationship between the logical channel (Downlink Logical Channel), the transport channel (Downlink Transport Channel), and the physical channel (Downlink Physical Channel) is shown. Below, they will be explained in order.

- CCCH (Common Control Channel): A logical channel used to transmit control information between the UE 5, the relay radio communication unit 9, and the EPC function unit 3, and is a logical channel used to transmit control information between the UE 5, the relay radio communication unit 9, and the EPC function unit 3, and the EPC function unit 3 and radio resources. Used by UE5 that does not have a control (RRC: Radio Resource Control) connection.
・DCCH (Dedicated Control Channel): A point-to-point bidirectional logical channel that transmits individual control information between the UE 5, the relay radio communication unit 9, and the EPC function unit 3. This is the channel used to transmit. The dedicated control channel DCCH is used by UE5s that have an RRC connection.
- DTCH (Dedicated Traffic Channel): A one-to-one bidirectional logical channel, which is dedicated to a specific UE or relay radio communication unit, and is used to transfer user information.

- It is a transport channel that supports ULSCH (Uplink Shared Channel: HARQ), dynamic adaptive radio link control, and discontinuous transmission (DTX).
- RACH (Random Access Channel): A transport channel on which limited control information is transmitted.

- PUCCH (Physical Uplink Control Channel): Response information for downlink data (ACK (Acknowledge)/NACK (Negative acknowledge)), downlink radio quality information (CQI: Channel Quality Indicator), and This is a physical channel used to notify the wireless base station section 4 of a request for transmission of uplink data (scheduling request: SR).
- PUSCH (Physical Uplink Shared Channel): A physical channel used to transmit uplink data.
- PRACH (Physical Random Access Channel): A physical channel mainly used for random access preamble transmission to obtain transmission timing information (transmission timing command) from the UE 5 to the radio base station section 4. Random access preamble transmission is performed during the random access procedure.

As shown in FIG. 7, in the uplink, transport channels and physical channels are mapped as follows. The uplink shared channel ULSCH is mapped to the physical uplink shared channel PUSCH. Random access channel RACH is mapped to physical random access channel PRACH. The physical uplink control channel PUCCH is used as a physical channel alone. Further, the common control channel CCCH, dedicated control channel DCCH, and dedicated traffic channel DTCH are mapped to the uplink shared channel ULSCH.

Next, in the downlink of the LTE system, the UE 5 and the relay radio communication unit 9 wirelessly connect to the radio base station unit 4 using OFDM (Orthogonal Frequency-Division Multiplexing) access (OFDMA). The OFDMA system is characterized as a two-dimensional multiple access system that combines frequency division multiplexing and time division multiplexing. Specifically, orthogonal subcarriers on the frequency axis and time axis are divided and allocated to UE5, and the subcarriers that are orthogonal on the frequency axis are divided so that the signal of each subcarrier becomes zero (0 point). . By dividing subcarriers and allocating them on the frequency axis, even if one subcarrier is affected by fading, it is possible to select another subcarrier that is unaffected. This has the advantage that subcarriers can be used and wireless quality can be maintained.

In the OFDMA system, a resource block (hereinafter also referred to as RB) defined on a virtual plane extending between a frequency axis and a time axis is employed as a radio resource. As shown in Fig. 8, RB is defined as a block obtained by dividing the above plane into a matrix at 180 kHz/0.5 msec, and each block divides 12 adjacent subcarriers at 15 kHz intervals on the frequency axis, and on the time axis. Contains one slot (7 symbols) of the frame. These RBs are assigned to the UE 5 and the relay radio communication unit 9, with two RBs adjacent on the time axis (1 msec) as one set. On the other hand, in the uplink of the LTE system, resource blocks with a similar concept are used as radio resources, except that SC-FDM (Single Career Frequency-Division Multiplexing) access (SC-FDMA) is adopted. In OFDMA, one resource block is divided into 12 subcarriers (bandwidth: 15 kHz) on the frequency axis, whereas SC-FDMA is a single carrier system in which division into subcarriers is not performed.

FIG. 9 shows an example of the configuration of a wireless network system of the present invention when the wireless communication unit 1 having the above configuration is employed. In the wireless network system, wireless communication unit groups 1(A) to 1(D) are arranged into adjacent wireless communication unit pairs (1(A) and 1(B), 1(B) and 1(C), 1( C) and 1(D)) base station cells (50(A) and 50(B), 50(B) and 50(C), 50(C) and 50(D)) partially overlap. , are cascade-connected by inter-unit radio bearers 55(A), 55(B), and 55(C). With this configuration, it can be easily understood that the connection topology between the wireless communication units 1 is extremely simplified. In this case, for example, UE 5 (A) (mobile terminal) connected to one of the pair of wireless communication units 1 (A) and 1 (B) and UE 5 (B) (mobile terminal) connected to the other IP packets can be transmitted and received via the unit pair 1(A), 1(B) and the inter-unit radio bearer 55(A) that connects the wireless communication unit pair 1(A), 1(B). For example, all of the wireless communication unit groups 1(A) to 1(D) may be mounted on a moving body such as the above-mentioned ship or vehicle, or only some of them may be mounted on a moving body, The remaining parts may be fixedly installed inside a building or the like.

Moreover, in FIG. 9, the number of wireless communication units cascade-connected by inter-unit radio bearers 55(A), 55(B), and 55(C) is three or more (four in FIG. 9). In this case, a UE (mobile terminal) 5 (A) connected to the first wireless communication unit 1 (A) forming one wireless communication unit of the wireless communication unit groups 1 (A) to 1 (D) and a wireless In communication unit groups 1(A) to 1(D), a second wireless communication unit disposed with one or more intermediate wireless communication units 1(B) and 1(C) separated from the first wireless communication unit 1(A) The UEs (mobile terminals) 5(C), 5(D) connected to the wireless communication units 1(C), 1(D) are connected to the first wireless communication unit 1(A), the intermediate wireless communication unit 1(B), 1(C) and second wireless communication units 1(C), 1(D), and an inter-unit radio bearer 55(A) that connects these wireless communication units 1(A) to 1(D). ), 55(B), and 55(C). In this way, the number of cascade-connected wireless communication units can be easily increased, and it becomes possible to transmit and receive IP packets by wireless communication between UE5s in a wider area.

In the wireless communication system according to the 3GPP specifications, one of a plurality of frequency bands defined by the 3GPP is assigned. The assigned frequency bands differ depending on the communication method, and for example, bands 1, 3, 6, 8, 11, 18, 19, 21, 26, 28, 41, and 42 are used as LTE bands. Each band is divided into a plurality of frequency channels with a predetermined bandwidth, and the EPC function unit 3 selects a predetermined frequency channel for the inter-unit radio bearer 55 and the terminal radio bearer 57 in FIG. It will be constructed as follows. That is, the downstream inter-unit channel, the upstream inter-unit channel, and the terminal-side channel are each set as a frequency channel belonging to one of a plurality of bands defined by 3GPP.

In the present embodiment, the EPC function unit 3 fixes the setting frequency channel of the (downstream) inter-unit radio bearer 55 to a (downstream) inter-unit channel that is one specific predetermined frequency channel. Furthermore, the terminal side channel, which is the set frequency channel of the terminal radio bearer 57, is set to the same frequency channel as the (downstream) inter-unit channel. That is, the EPC function section 3 sets the same frequency channel for the wireless base station section 4 directly below the relay wireless communication section 9 of the wireless communication unit 1 on the downstream side and the mobile terminal 5.

Next, in FIG. 9, what are cell 50 (A) of wireless communication unit 1 (A), cell 50 (B) of wireless communication unit 1 (B), and cell 50 (C) of wireless communication unit 1 (C)? They overlap with each other. In this case, for example, the inter-unit channel of the inter-unit radio bearers 55 (A), (B) connecting the upstream and downstream radio communication units 1 (A), 1 (C) as seen from the radio communication unit 1 (B) is By setting these to mutually different frequency channels, when constructing the inter-unit radio bearers 55(A) and (B), a plurality of cells 50(A) to 50(C) that are involved and partially overlap with each other are set. It is possible to effectively prevent radio wave interference between Furthermore, the terminal side channel is set to the same channel as the downstream inter-unit channel among the frequency channels belonging to the same band.

In this case, in a row of multiple wireless communication units 1 that are sequentially cascade-connected as shown in FIG. Regarding the communication units 1(A) to 1(D), it is desirable to set all the inter-unit channels of the inter-unit radio bearers 55(A) to 55(C) that connect these to different frequency channels. On the other hand, when another wireless communication unit is connected upstream or downstream of wireless communication units 1(A) to 1(D) whose connection path lengths are within the limit distance L, It is also possible to set the inter-unit channel of the inter-unit radio bearer that connects the wireless communication units to the same frequency channel as any of the inter-unit channels allocated to the wireless communication units within the limit distance L. For example, in FIG. 9, when connecting a new wireless communication unit further upstream of the wireless communication unit 1 (A), the upstream unit wireless communication of the wireless communication unit 1 (A) that is farthest from the new wireless communication unit The same frequency channel CH1 as the bearer can be set as the downstream inter-unit channel of the new wireless communication unit.

Furthermore, in this embodiment, the band 28 defined by 3GPP is adopted as the same band. The band 28 is set to the VHF band (700 MHz band), which has become vacant due to the discontinuation of terrestrial analog television broadcasting. Because Band 28 is a low frequency band and has somewhat slow communication speeds, it has not been actively adopted in areas with many terminal subscribers, such as urban areas, and the usage of radio wave resources is not as tight. Therefore, you can expect a smooth connection. Furthermore, the use of a low frequency band means that radio waves can reach long distances, and it is possible to expand the area (cell) that can be covered by one wireless communication unit. Furthermore, it has the property of being easy to connect even underground or when there are obstacles, and can be said to be suitable for constructing the wireless network system of the present invention, for example, on the sea or in a mine.

For example, when constructing the wireless network system shown in FIG. 9, the first wireless communication unit 1 (A) (relay wireless communication unit 9) attaches to the isolated wireless communication unit 1 (B) (wireless base station unit 4). When attaching, the wireless communication unit 1 (B) that receives the attach request selects a channel that it is not using from among the nine channels shown in FIG. 8 based on the connection status to other wireless communication units, and A) is notified using the MIB described below. In response to this, the radio communication unit 1 (A) performs channel settings for constructing an inter-unit radio bearer with the radio communication unit 1 (B). If the wireless communication unit 1 (B) is not connected to another wireless communication unit, the wireless communication unit 1 (B) uses an inter-unit radio bearer 55 (A) between the wireless communication unit 1 (A) and the wireless communication unit 1 (A). CH1 will be notified as the channel number used for construction.

Subsequently, when wireless communication unit 1 (B) attaches to the next wireless communication unit 1 (C) in FIG. The wireless communication unit 1 (B) inquires of the channel number (CH1) in use from the inter-radio bearer 55 (A), obtains information on the channel number (CH1), and then transmits the next number (CH2) of that channel to the wireless communication unit 1 (B). It is notified as a channel number used for constructing the inter-unit radio bearer 55(B) between. Similarly, the radio communication unit 1 (D) notifies the radio communication unit 1 (C) of the next channel number (CH3) as the channel number to be used for constructing the inter-unit radio bearer 55 (C). Although not shown in FIG. 9, if the number of interconnected wireless communication units further increases and all nine channels in FIG. Channel settings for use in inter-unit radio bearers are sequentially performed for communication units.

The flow of the attach sequence between the relay wireless communication unit 9 and the UE 5 will be described using FIGS. 10 and 11. FIG. 10 shows the attach sequence of the relay wireless communication unit 9. In the TS1, an attach request is issued from the relay radio communication unit 9 to the MME 2 via the radio base station unit (eNodeB) 4. By receiving the broadcast signal periodically output from the eNodeB4, the relay radio communication unit 9 can recognize that it has entered the cell (that is, within range) of the eNodeB4, and outputs an attach request to the eNodeB4. At this time, the IP address of the wireless communication unit is transmitted to the request source. In response to this, MME2 transmits a bearer setting request to S-GW6 in TS2. The S-GW 6 executes a physical line bearer setting process on the S5 interface with the P-GW 7 in TS3. Once the bearer is set up, the S-GW 6 transmits a bearer setup response to the MME 2 in TS4.

The MME 2 acquires the channel number that the requesting unit is using for the downstream inter-unit radio bearer in TS5, and in TS6 sends a radio bearer configuration request (attach acceptance) to the radio base station 4 with the configured channel number (obtained). the number of the adjacent channel). Upon receiving this, the radio base station unit 4 transmits an MIB (Master Information Block) including the setting channel number of the radio bearer (inter-unit radio bearer) to be set in TS7 to the relay radio communication unit 9. At TS8, the relay wireless communication section 9 fixes the inter-unit channel to the set channel number included in the received MIB, and returns a setting completion notification. In response to this, the wireless base station unit 4 notifies the relay wireless communication unit 9 of a session start request (touch acceptance) at TS9. At TS10, the relay radio communication section 9 sets up an inter-unit radio bearer and returns a session start response to the radio base station section 4. At TS11, the wireless base station unit 4 notifies the MME 2 of a session start response.

On the other hand, FIG. 11 shows the attach sequence of UE5 (mobile terminal). In the TS 11', an attach request is issued from the UE 5 to the MME 2 via the radio base station section (eNodeB) 4. At this time, the IP address of the wireless communication unit is transmitted to the request source. In response to this, MME2 transmits a bearer setting request to S-GW6 in TS12. In TS13, the S-GW 6 executes a physical line bearer setting process on the S5 interface with the P-GW 7. If the bearer is set up, the S-GW 6 transmits a bearer setting response to the MME 2 in TS14. The MME 2 determines a set channel number that can be used as a terminal radio bearer group according to the process shown in FIG. Then, at TS16, a radio bearer setup request (attach acceptance) is notified to the radio base station unit 4 along with the determined setup channel number. Upon receiving this, the radio base station section 4 transmits an MIB (Master Information Block) including the setting channel number of the radio bearer (inter-unit radio bearer) to be set in TS17 to the UE5. If there is a relay radio communication section of another radio communication unit connected to the radio base station section 4, the same channel number as that of the relay radio communication section 9 is used as this set channel number.

At TS18, the UE 5 sets the terminal side channel to the setting channel number included in the received MIB, and returns setting completion. In response to this, the radio base station unit 4 notifies the UE 5 of a session start request (attach acceptance) at TS19. At TS20, the UE 5 sets up a terminal radio bearer and returns a session start response to the radio base station section 4. At TS21, the wireless base station unit 4 notifies the MME 2 of a session start response. As described above, the attach sequence of the UE 5 and the attach sequence of the relay radio communication unit 9 are executed according to basically the same procedure except for the content of the frequency channel setting.

According to the above method, even if any of the multiple wireless communication units does not arbitrate channel settings, each wireless communication unit individually executes an attach sequence, thereby establishing a wireless bearer between downstream units of one wireless communication unit. There is an advantage that the upstream unit radio bearer and the upstream unit radio bearer can be set to different channels. On the other hand, in this method, the downstream inter-unit radio bearer and the upstream inter-unit radio bearer are set to adjacent channels in many radio communication units, and the relay radio communication unit and radio base installed in the same radio communication unit There is a problem in that the influence of wraparound interference caused by adjacent channel transmission waves becomes particularly large between the local area and the local area. Furthermore, even if channel settings are arbitrated between multiple wireless communication units in some way, if the number of connected wireless communication units increases, the upstream and downstream inter-unit radio bearers of all wireless communication units will be In practice, it is difficult to set channels that are not adjacent to each other.

However, by employing the high frequency antenna unit 250 of FIGS. 14 and 15, the above problem can be effectively solved. This will be explained in detail below. First, there are the following four cases in which a transmission wave from one of the relay radio communication unit 9 and the radio base station unit 4 becomes a loop interference wave with respect to the other.
(1) Wraparound interference of transmitted waves from the transmitting/receiving antenna 907TR to the receiving antenna 407R.
(2) Interference of the transmitted wave from the transmitting/receiving antenna 907TR to the transmitting/receiving antenna 407TR functioning as a receiving antenna.
(3) Wraparound interference of the transmitted wave from the transmitting/receiving antenna 407TR to the receiving antenna 907R.
(4) Interference of transmitted waves from the transmitting/receiving antenna 407TR to the transmitting/receiving antenna 907TR functioning as a receiving antenna.

As shown in FIG. 14, the antenna support plate 252(A) and the antenna support plate 252(B) support the transmitting/receiving antenna 907TR and the receiving antenna 907R (first transmitting/receiving antenna group) of the relay wireless communication section 9 on the lower side. The transmitting/receiving antenna 407TR and the receiving antenna 407R of the wireless base station section 4 are spaced apart so that the distance DV between the feeding points is λ/2 or more, and has the function of attenuating loop interference waves due to free space propagation loss. Therefore, in all cases (1) to (4) above, radio wave interference between the transmitting/receiving antenna 407TR and the receiving antenna 407R of the wireless base station section 4 arranged below is effectively suppressed. In this embodiment, as shown in FIG. 16, since a high-frequency antenna with strong upward directionality of radio wave intensity is employed, the lower radio base station section 4 in (3) or (4) is used. It can be said that this is even more effective when the transmitted wave by the side transmitting/receiving antenna 407TR is received as an interference wave by the transmitting/receiving antenna 907TR and receiving antenna 907R of the upper relay wireless communication section 9.

Further, the antenna support plate 252(A) is made of metal and functions as a metal shielding plate. In the case of (2) and (4) above, the propagation distance DP of the wraparound interference wave between the transmitting/receiving antenna 907TR of the relay wireless communication unit 9 and the transmitting/receiving antenna 407TR of the wireless base station unit 4 directly below it is Excluding the effect of , it is almost equal to the above DV. In this case, when the frequency of the transmitted and received waves is 700 MHz (λ=0.43 m) and DV=2λ, the free space propagation loss of the loop interference wave is about 28 dB. In addition, considering that multipath propagation occurs with reflection from metal shielding plates, when the actual propagation distance of the wraparound interference wave is estimated to be, for example, 1.5 to 3 times the above value, the wraparound interference wave It is also estimated that the free space propagation loss of the interference wave is about 31 to 38 dB.

On the other hand, in the case of (1) and (3) above, the upper and lower receiving antennas 907R and 407R are arranged horizontally apart from the corresponding transmitting and receiving antennas 907TR and 407TR by a distance DH, and the transmitting and receiving antennas are The propagation distance of the wraparound interference waves from the antennas 907TR, 407TR to the receiving antennas 907R, 407R can be made larger than in cases (2) and (4). Specifically, each propagation distance DP between the transmitting/receiving antenna 907TR and the receiving antenna 407R, and between the transmitting/receiving antenna 407TR and the receiving antenna 907R is geometrically calculated by excluding the effect of the metal shielding plate. It can be calculated as ((DV) ² + (DH) ² ) ^0.5 . For example, when DV=2λ and DH=3/2λ, DP=2.5λ, and the free space propagation loss when the frequency of the transmitted and received waves is 700 MHz (λ=0.43 m) is about 30 dB. In this case as well, if the actual propagation distance is estimated to be about 1.5 to 3 times the above value, taking into account the reflection from the metal shielding plate, the free space propagation loss of the wraparound interference wave will be about 33 to 40 dB. Guessed.

In addition, in any of the above cases, the larger the margin distances Mx and My shown in FIG. The wave attenuation effect can be increased. Furthermore, when the distance DV is less than λ/2, the effect of improving the isolation between the upper and lower high frequency antennas becomes insufficient. The distance DV is preferably maintained at λ (1 wavelength) or more, more preferably at least 1.5λ.

Next, in the configuration of FIG. 14, the upper transmitting/receiving antenna 907TR and the lower transmitting/receiving antenna 407TR are arranged in a positional relationship such that their null points NP overlap each other when projected onto the xy plane, as shown in FIG. Irha. This contributes to further reducing the influence of loop interference waves in cases (2) and (4) above. That is, the direction in which the interference wave directly propagates from one of the transmitting/receiving antenna 907TR and the transmitting/receiving antenna 407TR to the other is a direction that includes the null point NP of both antennas, and the radiation intensity of the transmitted wave and the sensitivity to the received wave are different. is also the minimum. Therefore, it can be said that the structure has a characteristic that the influence of interference due to direct waves between the upper and lower high-frequency antennas is extremely unlikely to occur.

If the influence of reflection by the metal shielding plate is taken into account, it is of course possible that a multipath interference wave having a horizontal component is received while bypassing the metal shielding plate. Here, for example, according to the chart in FIG. 16, the radio wave radiation intensity becomes high when the direction is angularly deviated to some extent (for example, about 5 to 20 degrees) from the z-axis direction where the null point is aligned. , the stronger the interference wave, the larger the angular distance from the z-axis. In other words, the propagation length of a reflected wave angularly deviated from the vertical direction until it is received by the other antenna increases as the deviation angle increases, and the effect of attenuation due to free space propagation loss is enhanced. In other words, the radiation intensity from the antenna is originally low in the angular region close to the direct wave, and the attenuation effect due to free space propagation loss is large in the angular region far from the direct wave, resulting in a null point between the upper and lower high-frequency antennas as described above. It can be said that it is advantageous to have a configuration in which the following are combined, even when a metal shielding plate is provided, in order to further reduce wraparound interference waves.

Further, in FIG. 14, transmitting/receiving antenna groups 907TR and 907R connected to the relay wireless communication section 9 are arranged on the uppermost antenna support plate 252(A). As a result, when constructing an inter-unit radio bearer, obstacles to uplink transmission waves with relatively low radio field strength, particularly from the relay radio communication unit 9, are removed from the support frame 251, so that the relay radio communication The uplink throughput of the unit 9 can be increased. Furthermore, the lower antenna support plate 252 (B) is also made of metal, similar to the upper antenna support plate 252 (A). The antenna support plate 252 (B) increases the volume of the ground metal by being in close conductive contact with the metal base 200B of the high frequency antenna, and plays the role of stabilizing the ground potential.

Note that the transmitting and receiving antenna groups of the relay wireless communication unit 9 and the wireless base station unit 4 in FIG. 3 are simply transmission-only antennas 907T, 407T, reception-only antennas 907R, 407R, the combination of high-frequency antennas that match the null points is the upper transmission-only antenna 907T and the lower reception antenna 407R, and the upper reception-only antenna 907R and the lower transmission antenna. It may be 407T.

Various modifications of the high frequency antenna unit of the present invention will be described below. Note that parts common to the configurations shown in FIGS. 14 and 15 are given the same reference numerals and detailed explanations are omitted. First, if the interference wave reduction effect of the upper antenna support plate 252(A) (metal shielding plate) is sufficiently large, as shown in FIG. It is also possible to arrange the antennas 907TR and 907R in a positional relationship in which they do not overlap each other in plan view. Further, FIG. 19 shows an embodiment in which the distance DV between the upper and lower antennas is reduced to the lower limit value λ/2 of the present invention.

Furthermore, as shown in FIG. 20, the high frequency antennas 907TR, 907R and the high frequency antennas 407TR, 407R can be arranged along the diagonal of the rectangular plate surface of each antenna support plate 252(A), 252(B). . Thereby, the distance between the high frequency antennas on the antenna support plate can be further increased. In FIG. 20, the upper and lower high-frequency antennas 907TR, 907R and 407TR, 407R are arranged along the diagonal line in the same direction of each antenna support plate 252(A), 252(B) so that the null points overlap each other in plan view. It is located in However, in cases where the interference wave reduction effect of the upper antenna support plate 252(A) (metal shielding plate) is sufficiently large, as shown in FIG. It is also possible to arrange the high frequency antennas 907TR and 907R along a diagonal line in a different direction.

FIG. 22 shows an example in which the main parts of the upper and lower antenna support plates 252'(A) and 252'(B) are made of an insulating material, and the metal shielding plate is omitted. As shown in FIG. 23, the antenna support plates 252'(A) and 252'(B) are made of metal frames 252f(A) and 252f(B) supported by the pillars 253, and resin or metal frames supported by the metal frames 252f(A) and 252f(B). It has main bodies 252p (A) and 252p (B) made of insulating material plates such as wood. As shown in FIG. 22, the high frequency antennas 907TR, 907R and the high frequency antennas 407TR, 407R are fixed on the main bodies 252p (A), 252p (B), and their respective metal mounting plates 201 are connected by conductive wires GW. It is coupled to frames 252f (A) and 252f (B) that function as ground conductors. With this configuration, the effect of detouring and attenuating the wraparound interference waves by the metal shielding plate cannot be expected. Therefore, the distance between the upper and lower antenna support plates 252'(A) and 252'(B) was slightly increased from the configuration shown in FIG. 14, and the distance DV between the feeding points of the antenna was slightly increased from 2λ in FIG. 14 to 2.5λ. There is.

In the case of (2) and (4) above, if the frequency of the transmitted and received waves is 700 MHz (λ = 0.43 m) and DV = 2.5 λ, the free space propagation loss of the loop interference wave will be approximately 30 dB from approximately 28 dB in Figure 14. will be improved. In addition, in the case of (1) and (3), when DV = 2.5λ and DH = 3/2λ, DP = 2.9λ, and the freedom when the frequency of the transmitted and received waves is 700MHz (λ = 0.43m). The spatial propagation loss is approximately 31 dB, which is improved from 30 dB in the case of FIG.

Next, the high frequency antenna unit 1250 shown in FIG. 24 is provided with antenna support plates in a form corresponding to each of the transmitting antennas and receiving antennas included in the plurality of transmitting and receiving antenna groups, and on the first main surface of the antenna support plates. 2 shows an example in which either the transmitting antenna or the receiving antenna is fixed. That is, the four high frequency antennas 200 (907TR, 907R, 407TR, 407R) included in the high frequency antenna unit 1250 in FIG. ) are attached to each separately. The antenna support plates 252(C) to 252(F) are arranged so that the distance DV between the vertically adjacent high-frequency antennas 200 is λ/2 or more ((3/4)λ in FIG. 24), as in FIG. 14. , are supported by pillars 253.

In the configuration of the high frequency antenna unit 1250 in FIG. 24, the number of high frequency antennas 200 supported by each antenna support plate 252(C) to 252(F) is only one, and compared with the high frequency antenna unit 250 in FIG. Therefore, there is an advantage that the installation area of the support frame 251 can be significantly reduced. Further, FIG. 25 is a table showing a preferable arrangement order of the four high-frequency antennas 907TR, 907R, 407TR, and 407R of FIG. 14 with respect to each antenna support plate 252(C) to 252(F). In the example shown in the upper row of the table, from the uppermost antenna support plate 252(C) to the lower antenna support plate 252(F), the transmitting/receiving antenna 907TR of the relay wireless communication section 9 and the receiving antenna 907R (the first The receiving antenna 407R of the radio base station section 4, and the transmitting/receiving antenna 407TR (hereinafter referred to as the second transmitting/receiving antenna group) are arranged in this order.

In this arrangement, by disposing the transmitting/receiving antenna 907TR on the top antenna support plate 252(C), similar to the configuration of FIG. Obstacles to transmitted waves are removed from the support frame 251, and uplink throughput by the relay wireless communication unit 9 can be increased. By arranging the transmitting/receiving antenna 407TR of the wireless base station section 4, which has a relatively large transmission output, at the lowest stage, the distance to the transmitting/receiving antenna 907TR and receiving antenna 907R of the relay wireless communication section 9 can be made shorter than in the configuration of FIG. It is possible to further expand the free space propagation loss of the wraparound interference waves toward these antennas.

Note that if the distance between the antenna support plates 252 is sufficiently large or the radio wave shielding effect by the antenna support plates 252 (D) is sufficiently large, the transmission and reception of the relay wireless communication unit 9 will be as shown in the lower part of the table in FIG. The vertical arrangement of the antenna 907TR and the receiving antenna 907R may be reversed. Furthermore, as in the high-frequency antenna unit 1250' shown in FIG. 26, an antenna support plate other than the antenna support plate 252(D) functioning as a metal shielding plate may be replaced with an insulated antenna support plate 252'(C) similar to that shown in FIG. ), an antenna support plate 252'(E), and an antenna support plate 252'(F).

Furthermore, as shown in FIG. 27, by further expanding the distance between the antenna support plates, all the antenna support plates are configured as insulated antenna support plates 252' (C) to 252' (F). You can also. In this case, as shown by the dashed line in the figure, it is also possible to provide a metal shielding plate 252M in addition to the antenna support plate at a position that separates the first transmitting/receiving antenna group and the second transmitting/receiving antenna group. The metal shielding plate 252M has the same configuration as the antenna support plate shown in FIG. 14, and is supported by a support 253 at an intermediate position in the height direction of the upper and lower antenna support plates 252'(D) and 252'(E). There is.

Although the embodiments of the present invention have been described above, the present invention is not limited to these, and various modifications can be made without departing from the gist of the present invention. For example, in the wireless communication unit 1 of FIG. 3, it is also possible to mount a plurality of one or both of the relay wireless communication section 9 and the wireless base station section 4. In this case, three or more corresponding transmitting/receiving antenna groups are required, but the high frequency antenna unit of the present invention shown in FIG. It is possible to have a configuration in which they are arranged at intervals of .

1(A), 1(B) Wireless communication unit WS(A), WS(B) Large ship 2 MME
3 EPC function section 301 CPU
302 RAM
303 Mask ROM
304A Upstream communication interface 304B Downstream communication interface 305 Flash memory 305a Communication firmware 305b MME entity 305c S-GW entity 305d P-GW entity 306 Bus 21 Secondary battery module 22 Power supply circuit unit 23 Portable housing 30, 31 Communication bus 4 Wireless base station section 401 CPU
402 RAM
403 Mask ROM
404 Communication interface 405 Flash memory 405a Communication firmware 406 Bus 407TR Transmission/reception antenna 407R Receiving antenna 412 Wireless communication unit 5 UE (mobile terminal)
6 S-GW
7 P-GW
8 Router 9 Relay wireless communication section 901 CPU
902 RAM
903 Mask ROM
905 Flash memory 905a Communication firmware 906 Bus 907TR transmitting/receiving antenna 907R Receiving antenna 912 Wireless communication section 50(A), 50(B) Communication area 55 Inter-unit radio bearer 57 Terminal radio bearer 200 High frequency antenna 200B Metal base 201 Metal mounting plate 202 Antenna feed plate 203 Antenna element 251 Support frame 252 Antenna support plate 252h Insertion hole 250 High frequency antenna unit 255 Fastening member AD Arrangement direction NP Null point

Claims (12)

Comprising a plurality of high frequency antennas and a support frame body to which the high frequency antennas are attached,
The plurality of high-frequency antennas include a plurality of transmitting/receiving antenna groups each including a transmitting antenna and a receiving antenna connected to the same transmitting/receiving device, and the plurality of transmitting/receiving antenna groups are arranged in a predetermined arrangement direction with respect to the support frame. They are fixedly attached at predetermined intervals, and are planned to be connected to different transmitting and receiving devices.
The support frame includes a plurality of antenna support plates arranged at predetermined intervals in the arrangement direction and each having a plate surface with the arrangement direction as a normal direction,
The transmitting antenna and the receiving antenna constituting the transmitting and receiving antenna group are attached to the plurality of antenna support plates in a distributed manner, and
The high-frequency antennas attached to a pair of antenna support plates adjacent to each other in the arrangement direction are such that a distance between feeding points of the high-frequency antennas in the arrangement direction is determined to be equal to or more than 1/2 wavelength of the transmitted and received waves. A high frequency antenna unit that is characterized by: The transmitting antenna and the receiving antenna constituting the same transmitting and receiving antenna group are mounted on the first main surface of the corresponding antenna support plate with a predetermined antenna spacing determined to be equal to or more than 1/4 wavelength of the transmitted and received waves. The high frequency antenna unit according to claim 1. The antenna support plate is provided in a form corresponding to each of the transmitting antennas and the receiving antennas included in the plurality of transmitting and receiving antenna groups, and the transmitting antenna and the receiving antenna are provided on the first main surface of the antenna support plate. The high frequency antenna unit according to claim 1, wherein any one of the antennas is fixed. The support frame is provided with a metal shielding plate having a plate surface whose normal direction is the arrangement direction, at a position that separates two transmitting/receiving antenna groups that are arranged adjacent to each other in the arrangement direction. The high frequency antenna unit according to any one of claims 1 to 3. 5. The high frequency antenna unit according to claim 4, wherein at least some of the plurality of antenna support plates are made of metal and are also used as the metal shielding plate. The high frequency antenna according to claim 5, wherein the high frequency antenna includes a metal base and a metal antenna element attached to the metal base, and is fixed to the metal shielding plate in an electrically conductive manner by the metal base. unit. The metal substrate has a metal mounting plate for attaching the metal substrate to the metal shielding plate, and the antenna element is attached to a first major surface of the metal mounting plate, while the metal mounting plate has a second major surface. 7. The high frequency antenna unit according to claim 6, wherein the high frequency antenna unit is attached in close contact with the first main surface of the metal shielding plate. 8. The high-frequency antenna unit according to claim 7, further comprising a fastening member that is provided to penetrate the metal mounting plate and the metal shielding plate and fasten the metal mounting plate and the metal shielding plate in close contact with each other. The high frequency antenna includes a metal base and a metal antenna element attached to the metal base, and is fixed to the antenna support plate by the metal base, and the metal base attaches the metal base to the antenna support plate. Has a metal mounting plate for
A fastening member is provided to penetrate the metal mounting plate and the antenna support plate and fasten the metal mounting plate and the antenna support plate in close contact with each other, and is removably provided with respect to the antenna support plate;
A plurality of insertion holes into which the fastening member can be attached are formed in the antenna support plate and are distributed at predetermined intervals as units of position change,
Claim: The fastening member is mounted in such a manner that the metal mounting plate is positioned at a desired position on the antenna support plate, and one of the plurality of insertion holes is selected at a position corresponding to the antenna support plate. The high frequency antenna unit according to any one of claims 1 to 8. The high frequency antenna includes a metal base and a metal antenna element attached to the metal base, and is fixed to the antenna support plate by the metal base, and the metal base is fixed to the antenna support plate by the metal base. Has a metal mounting plate for mounting;
The metal base includes an antenna feed plate disposed parallel to the antenna support plate, and the antenna element has a first end connected to the first main surface of the antenna feed plate, which serves as an antenna feed point, and a second end free. 10. The high frequency antenna unit according to claim 1, wherein the high frequency antenna unit is configured as a rod-shaped omnidirectional antenna that protrudes from the antenna feed plate so as to form an end thereof. A wireless communication unit configured to be mounted on a mobile body and for performing wireless network communication with a mobile terminal,
a radio base station unit to which the mobile terminal can connect via a terminal radio bearer; an EPC (Evolved Packet Core) functional unit that is connected by wire to the radio base station unit and functions as an upper network control unit for the radio base station unit; The radio base station section of the upstream unit (hereinafter referred to as the upstream radio base station section) is connected to the EPC function section by wire, and is a first separate wireless communication unit, and the upstream unit radio bearer (hereinafter referred to as the upstream unit inter-unit radio bearer) A relay radio communication unit connectable via a relay radio communication unit (hereinafter referred to as a radio bearer) of a downstream unit that is a second separate radio communication unit (hereinafter referred to as a downstream relay radio communication unit). ) and a wireless unit main body that can be connected via a downstream inter-unit radio bearer (hereinafter referred to as a downstream inter-unit radio bearer);
comprising a plurality of high frequency antennas and a support frame body to which the high frequency antennas are attached, the plurality of high frequency antennas including a first transmitting/receiving antenna group consisting of a transmitting antenna and a receiving antenna connected to the relay wireless communication section; a second transmitting/receiving antenna group consisting of a transmitting antenna and a receiving antenna connected to the wireless base station section, and the plurality of transmitting/receiving antenna groups are arranged at predetermined intervals in a predetermined arrangement direction with respect to the support frame. and are fixedly attached to each other, and are planned to be connected to different transmitting and receiving devices, respectively, and the support frames are arranged at predetermined intervals in the arrangement direction, with the arrangement direction being the normal direction. a plurality of antenna support plates each having a plate surface, the transmitting antennas and the receiving antennas constituting the transmitting/receiving antenna group are distributed and attached to the plurality of antenna support plates; A high-frequency antenna unit in which the high-frequency antennas attached to the antenna support plate are such that the distance between feeding points of the high-frequency antennas in the arrangement direction is set to be equal to or more than 1/2 wavelength of the transmitted and received waves;
A wireless communication unit characterized by comprising: The radio communication unit according to claim 11, wherein the upstream inter-unit radio bearer and the downstream inter-unit radio bearer are configured using frequency channels adjacent to each other within the same frequency band.

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