JP2004515111A - Multiple beam dispersion / combination device for mobile communication system - Google Patents

Abstract

In a multiple beam dispersing / combining apparatus of a mobile communication system, wherein a base station has n sectors having m multiple beams for each sector, the base station forms (nxm) beams having different radiation angles from each other. Combining the (n × m) beams from the multiple beam forming module into (n × m) / 2 beams, each distributed between two sectors, 180 A coupler module; a switch module having (m × n) switch elements for selecting one of the distributed (n × m) beams or a termination load; and a distributed (n × m) A 180 ° phase transition module for selectively shifting the phases of the beams; and a combining module for combining (m / 2) beams for each sector. According to the present invention, the data traffic of the base station is evenly distributed in n sectors.

Description

[0001]
1. TECHNICAL FIELD The present invention relates to a multi-beam dispersing / combining apparatus for a mobile communication system in which a service area of a sector is variably adjusted according to a traffic load distribution of each sector in the mobile communication system.
[0002]
2. BACKGROUND ART In a mobile communication system, mobile communication base stations (BTS) are classified into omni base stations and sector base stations. However, most base stations are of the sector base station type. In a sector type base station (BTS), its service area is divided into three sectors or six sectors. A sector type BTS in a CDMA base station generally has three sector base stations.
[0003]
A sector-type BTS uses an antenna having a fixed beam width for each sector. Therefore, the geographical range of the service area of the sector is fixed. However, since traffic is usually unbalanced between BTS sectors, sufficient frequency resources are allocated to the sector that processes the largest traffic. As a result, the efficiency of frequency resources is reduced in a sector with a small amount of traffic, and the radio channel efficiency is reduced in a sector with a large concentration of traffic, thereby reducing the coverage. This causes problems such as a decrease in service efficiency and an increase in frequency resource management / maintenance costs in a BTS having a traffic imbalanced sector.
[0004]
Furthermore, if the traffic load distribution changes between three sector base stations in a BTS with sectors each having a fixed service area, such situations are handled manually. That is, the operator suitably changes the direction of the antenna provided on the tower in order to adapt the change in the traffic load distribution. However, such a manual operation is not only extremely dangerous and troublesome, but also takes a long time to adjust the antenna. As a result, manual maintenance is inefficient.
[0005]
3. DISCLOSURE OF THE INVENTION It is an object of the present invention to distribute the beams of a sector to other sectors based on the traffic load distribution in order to ensure the traffic balance between the sectors and the efficient use of the frequency resources of the BTS. An object of the present invention is to provide a multiple beam dispersion / combination device of a mobile communication system that adjusts each service area.
[0006]
A multiple beam dispersing / combining apparatus for a mobile communication system according to the present invention, wherein the base station has n sectors having m multiple beams for each sector, A multiple beamforming module for forming (nxm) beams with different emission angles; and (nxm) beams from said multiple beamforming module, each distributed between two sectors. 180 ° coupler module for combining into (n × m) / 2 beams; and (m × n) switches to select one of the distributed (n × m) beams or a termination load A switch module having elements; a 180 ° phase transition module for selectively shifting the phase of the distributed (n × m) beams; and combining (m / 2) beams for each sector That the synthesis module; is characterized in point comprised.
[0007]
Another multiple beam dispersing / combining apparatus for a mobile communication system according to the present invention is a multiple beam dispersing / combining apparatus for a mobile communication system, wherein the base station has n sectors having m multiple beams for each sector. A multi-beam forming module for forming (n × m) beams having different radiation angles from each other; and (n × m) output beams formed by the multi-beam forming module selectively (n × m). and m) a switch module having a switch element for connecting two beams to two sectors; a switch module comprising: a plurality of sector couplers and a plurality of common couplers; (N × m) / 2 beams are combined via the switch module without passing through the switch module, and each of the common couplers A coupler module capable of combining two beams from elements and distributing the combined beam between the two sectors; and a combining module combining all outputs from the coupler module for each sector. , Is characterized by the following.
[0008]
Another multiple beam dispersing / combining apparatus for a mobile communication system according to the present invention is a multiple beam dispersing / combining apparatus for a mobile communication system, wherein the base station has n sectors having m multiple beams for each sector. A coupling module for combining said (nxm) beams to generate a traffic criterion signal for each sector; each capable of combining each input to two sectors. , Switch matrix module having (nxm) switch elements; termination switch matrix module having 2x (nxm) termination switch elements, each selecting the output of said switch element or termination load A combining module for combining all outputs from the termination switch matrix module for each sector; Based on Hick criteria signals, and a control unit for individually controlling the switching operation of said switching element and said termination switch element, is characterized in comprising a.
[0009]
The multiple beam dispersing / combining apparatus of the mobile communication system enables efficient use of frequency resources, and improves security and convenience of maintenance through traffic balancing among all sectors. Such a multiple beam dispersing / combining device reduces the number of switches required to switch the beams, and thus safe operation of beam changes can be achieved.
[0010]
5. BEST MODE FOR CARRYING OUT THE INVENTION In order to fully understand the present invention, preferred embodiments will be described below with reference to the accompanying drawings.
[0011]
First, a first embodiment of the present invention will be described. In the first embodiment of the present invention, four beams for each sector (a total of 12 for three sectors) are combined into two beams, and a total of six beams are adaptively divided into three based on the traffic distribution. It is distributed to one of the sectors.
[0012]
That is, as shown in FIG. 1, the six beams form a complete BTS service area, and the direction and width of the sector are adjusted through the redistribution of the beams.
[0013]
FIG. 2 is a block diagram of a first embodiment of the multiple beam dispersion / combination apparatus according to the present invention. The apparatus of FIG. 2 includes a multiple beam forming module 102, a 180 ° coupler module 104, a switch module 106, a 180 ° phase transition module 108, and a combining module 110.
[0014]
The multiple beam forming module 102 forms twelve beams having different radiation angles from each other, and includes three multiple beam formers for three sectors as shown in FIG. The four RF beams output from each multiplex beamformer are provided to two 180 ° coupler modules 104.
[0015]
A 180 ° coupler module 104 having six 180 ° couplers combines 12 RF beams into 6 RF beams. That is, each 180 ° coupler in the 180 ° coupler module 104 combines each two RF beams into one beam. And every 180 ° coupler has two output signal paths, one connected to the signal port of the original sector and the other connected to the signal port of the other sector.
[0016]
The switch module 106 selects the output of the 180 ° coupler when the signal is output from the 180 ° coupler. According to the 180 ° coupler module 104 and the switch module 106, each beam is adaptively distributed to one of three sectors. The 180 ° phase transition module 108 shifts the phase of the output signal of the switch received signal from the other sector in order to constructively mix the signal from the other sector in the next combining module 110.
[0017]
The combining module 110 matches the amplitude and phase characteristics of the beams on all signal paths from the multiple beamforming module 110 with each other. The synthesis module 110 can be configured as a 4-way synthesizer.
[0018]
According to the operation of the first embodiment of the multiple beam dispersing / combining device, the six beams can each be distributed to sectors other than the original sector in order to adapt to changes in the traffic load distribution among the three sectors. , The radio channel is maximized.
[0019]
Next, a second embodiment of the present invention will be described. In the second embodiment, four beams for each three sectors (a total of 12 beams for three sectors) are used, and the four beams are composed of two fixed beams and two variable beams (hereinafter referred to as 'adaptive'). Beam '). The two adaptive beams in each sector are adaptively redistributed to other sectors based on the traffic distribution.
[0020]
That is, as shown in FIG. 3, the 12 beams form the entire service area of the BTS, and the six fixed beams A2, A3, B2, B3, C2, and C3 are fixed to these original sectors. , And the other six adaptive beams A1, A4, B1, B4, C1, and C4 are variable between sectors. Thus, the direction and width of the sectors are adjusted via adaptive beam redistribution.
[0021]
FIG. 4 is a block diagram of a second embodiment of the multiple beam dispersion / combination apparatus according to the present invention. The apparatus shown in FIG. 4 includes a multiple beam forming module 402, a switch module 404, a 180 ° coupler module 406, and a combining module 408.
[0022]
The multiple beamformer module 402 forms 12 beams such that their radiation angles are different from each other, and includes three multiple beamformers for three sectors as shown in FIG. In each multiple beamforming phase, the four beams received from the array sectors are formed such that the four beams have different service area cells, which make up all the service areas of the corresponding sector.
[0023]
The switch module 404 of the second embodiment has six switches arranged for the six beams A4, B1, B4, C1, C4, and A1, which are initially formed as "sector variable". . Each switch of the multiple beamforming module 402 receives the adaptive beam from the multiple beamforming module 402 and connects to one or both original sectors or other sectors.
[0024]
Each switch in the switch module 404 includes two outputs and one termination load. One output has a fixed connection with the input, and the other output is selectively connected to the input or the terminating load according to external control or an internal control signal of the switch module 404. That is, each switch forms a single beam path to the output port of the original sector only, or two paths to both the sector and other sectors. In other words, each switch functions as a 2-way distributor when turned on, and functions as a single beam path when turned off.
[0025]
The switches connect to the beam ports A1, A4, B1, B4, C1 and C4 operating in pairs. In other words, the two switches, A4 and B1, B4 and C1, and C4 and A1, are linked in the switch operation. For example, two switches for the A4 and B1 ports are turned off at the same time, and when the other is turned off, one of the two is turned on. In other words, each switch pair does not set a route to another sector, or uses only a single route to another sector under the external ON / OFF control signal or the internal ON / OFF control signal of the switch module 404. Set.
[0026]
Each coupler of the 180 ° coupler module 406 has two inputs and two or one (otherwise terminated) outputs, which shift the phase of the rectangular input by 180 ° and then directly Combine with input.
[0027]
Combining module 408 matches the beams in their amplitude and phase characteristics on all signal paths from multiple beamforming module 402. Combining module 408 may be a 4-way combiner.
[0028]
The operation of the second embodiment will be described in more detail by way of example.
[0029]
When the pair of switches A4 and B1 are all OFF, the beam paths to other sectors are not established because the two adaptive beams A4 and B1 are fixed to their original sectors, respectively. When all the switch pairs are OFF, the sector type BTS has 12 fixed beams as in the related art.
[0030]
If switch A4 of the two is ON and the other B1 is OFF, beam A4 is split by switch A4, which functions as a two-way combiner, and the two 180 ° couplers (ie, between sectors 1 and 2). At the same time, are applied to the 180 ° coupler and the common 180 ° coupler of the sector 1 arranged at the same time.
Beam A4 applied to the 180 ° coupler in sector 1 is shifted 180 °, and no phase shift occurs in beam A4 applied to the shared 180 ° coupler. Thus, the distribution beam A4 is destructively mixed in the combiner of sector 1 such that beam A4 disappears in sector 1.
[0031]
On the other hand, the beam A4 applied to the 180 ° coupler is also phase-shifted by 180 ° at the output terminal connected to the sector 2 and input to the combiner of the sector 2. The 180 ° shifted beam A4 is combined with the beam B4 shifted by 180 ° and the other beams of the sector 2 in the combiner of the sector 2. Therefore, the beam A4 is redistributed from the sector 1 to the sector 2, that is, the service area of the sector 2 is expanded.
[0032]
Similarly to the operation described above, when the switch A4 is turned off and the other B1 is turned on, the beams A4 and B1 are used to redistribute the beam B1 to the sector 1. The signals are combined in one combiner. A detailed description of such a case will be omitted because it is obvious to a person skilled in the art.
[0033]
According to the operation of the second embodiment of the multi-beam composite dispersion / synthesis apparatus, six out of twelve are respectively allocated to sectors other than these original sectors in order to adapt to the change of traffic load distribution among three sectors. Can be distributed, maximizing the efficiency of the wireless channel.
[0034]
Next, a third embodiment of the present invention will be described. In the third embodiment, four beams are used for each three sectors (a total of 12 beams for three sectors), which can be adaptively redistributed to other sectors based on traffic distribution. Thus, all 12 beams are sector variable.
[0035]
FIG. 5 is a block diagram of a third embodiment of the multiple beam dispersion / combination apparatus of the present invention. 5 includes a directional coupling module 502, a switch matrix module 504, a terminal switch matrix module 506, a beam combining / dispersing module 508, and a control means 600.
[0036]
The directional coupling module 502 combines an RF beam from an array antenna (not shown) to extract a partial signal of the RF beam. The combined signal is used as a criterion for adaptive beam redistribution of the multiple beam dispersion / combining device 500, and can also be used for traffic estimation on the reverse link.
[0037]
The switch matrix module 504 connects or diverts the output from the directional coupling module 502 to the preferred sector and matches the signal characteristics between the directional coupling module 502 and the terminating switch matrix module 506.
[0038]
Termination switch matrix module 506 connects the signal from switch matrix module 504 to its output or termination when no signal is present. Furthermore, the signal characteristics between the switch matrix module 504 and the beam combining / dispersing module 508 are matched.
[0039]
The beam combining / dispersing module 508 prepares to combine / distribute the three sectors into multiple beams to match the characteristics of the signals transmitted / received to / from the BTS system.
[0040]
The control unit 600 controls the switch operation of both the switch matrix module 504 and the terminal switch matrix module 506,
These switching states are continuously monitored.
[0041]
FIG. 6 is a detailed block diagram of the multiple beam dispersion / combination device 500 of FIG. As shown in FIG. 6, the directional coupling module 502 has twelve input terminals connected to three array antennas to generate the decision signal and connect the twelve beams to the switch matrix module 504. Connect the 12 beams from.
[0042]
The switch matrix module 504 has twelve switches, and matches the signal characteristics between the directional coupling module 502 and the terminal switch matrix module 506 under the control of the control unit 600. Further, each switch of the switch matrix module 504 selects one of the beam paths to the two sectors under the control of the control unit 600. For beam path selection, each switch of the switch matrix module 504 has one input (connected to the directional coupling module 502) and two outputs connected to two termination switches belonging to different sectors. . Therefore, one of the two sectors is determined by the switch operation of each switch.
[0043]
The termination switch matrix module 506 has 24 termination switches, and under the control of the control unit 600, matches the signal characteristics between the switch matrix module 504 and the beam dispersion / combination module 508. Each termination switch of the termination switch matrix module 506 has two inputs, one connected to the switch matrix module 504 and the other connected to the termination load. Thus, the output of each terminal switch is connected to the corresponding switch of the switch matrix module 504 when outputting a signal or when connected to a terminal load under the control of the control unit 600. The switching to the terminating load is for preventing not only the impedance matching of the switch matrix module 504, the terminating switch matrix module 506, and the beam dispersion / combining module 508, but also to prevent unnecessary noise from flowing into the system.
[0044]
As can be seen from the description of all elements of the device shown in FIGS. 5 and 6, the traffic load of each sector is evaluated based on the signal extracted from the path coupled by the directional coupling module 502, and the traffic load of each sector is evaluated. Based on the estimated traffic load, it is determined how to split / combine the multiple beams. Next, the control unit 600 sets all physical signal paths via the switch matrix module 504 and the termination switch matrix module 506 by controlling each switching according to the determined multiple beam dispersion / combining scheme. I do. The physical signal path is set by the control unit 600 that performs a physical change of the sector.
[0045]
In the embodiments described above, for example, the number of beams, the number of sectors, and the structure of the twelve switches can be variously modified and modified without departing from the spirit and scope of the present invention. It will be apparent to those skilled in the art. Accordingly, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
[Brief description of the drawings]
BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention, illustrate preferred embodiments of the invention, together with the detailed description, and are provided to explain the principles of the invention.
FIG.
FIG. 1 is an exemplary beam pattern radiated by the multiple beam dispersing / combining device of the mobile communication system according to the present invention;
FIG. 2
FIG. 2 is a block diagram of a first embodiment of a multiple beam dispersion / combination apparatus according to the present invention.
FIG. 3
FIG. 3 is an exemplary sector fixed and sector variable beam emitted by the second embodiment of the multi-beam combined dispersion / combination device of the mobile communication system according to the present invention;
FIG. 4
FIG. 4 is a block diagram of a second embodiment of the multi-beam composite dispersion / combination apparatus according to the present invention.
FIG. 5
FIG. 5 is a block diagram of a third embodiment of the multiple beam dispersion / combination device of the mobile communication system according to the present invention, and
FIG. 6
FIG. 6 is a detailed block diagram of the multiple beam dispersion / combination apparatus of FIG.

Claims (14)

In a multiple beam dispersing / combining apparatus for a mobile communication system, wherein a base station has n sectors having m multiple beams for each sector,
A multi-beamforming module for forming (nxm) beams with different emission angles;
A 180 ° coupler module for combining the (n × m) beams from the multiple beamforming module into (n × m) / 2 beams, each distributed between two sectors;
A switch module having (m × n) switch elements for selecting one of the distributed (n × m) beams or a terminating load;
A 180 ° phase transition module for selectively shifting the phase of the distributed (n × m) beams;
A combining module for combining (m / 2) beams for each sector;
A multi-beam dispersing / combining apparatus for a mobile communication system, comprising: The 180 ° coupler module distributes each combined beam between the original sector and another sector;
The apparatus for multiplexing and dispersing multiple beams in a mobile communication system according to claim 1, wherein: The switch module selects each of the synthesized (n × m) / 2 beams into a single sector;
The apparatus for multiplexing and dispersing multiple beams in a mobile communication system according to claim 1, wherein: The 180 ° phase transition module shifts half of the distributed (n × m) beams to constructively combine, half from another sector;
The multiple beam dispersion / combination apparatus for a mobile communication system according to claim 1 or 2, wherein: In a multiple beam dispersing / combining apparatus for a mobile communication system, wherein a base station has n sectors having m multiple beams for each sector,
A multi-beamforming module for forming (nxm) beams with different emission angles;
A switch module having a switch element for selectively connecting (n × m) / 2 beams to two sectors from the (n × m) output beams formed by the multiple beam forming module;
The switch module comprises a plurality of sector couplers and a plurality of common couplers. The sector coupler transmits (n × m) / 2 beams without passing through the switch module and transmits (n × m) / 2 beams to the switch module. A coupler module, wherein each said common coupler is capable of combining two beams from said two switch elements and distributing the combined beam between two sectors;
A combining module for combining all outputs from the coupler module for each sector;
A multiplex beam dispersion / combination apparatus for a mobile communication system, comprising: The coupler module constantly transmits the (n × m) / 2 beams directly to the original sector, and transmits the other (n × m) / 2 beams to both the original sector and the other sectors. Can be transmitted simultaneously,
The multiple beam dispersion / combination apparatus for a mobile communication system according to claim 5, wherein: The coupling module transmits one of the distributed beams to the original sector without phase shift by each switch element;
The other distributed beams are transmitted to the original sector with a phase shift of 180 °,
Further, the one beam is transmitted to another sector with a phase shift of 180 °.
The multiple beam dispersion / combination apparatus for a mobile communication system according to claim 5, wherein: The switch element outputs an input beam to the sector coupler and the shared coupler simultaneously when an ON signal is applied, and outputs an input beam only to the sector coupler when an OFF signal is applied.
The multiple beam dispersion / combination apparatus for a mobile communication system according to claim 5 or 7, wherein: The synthesis module further comprises:
Combining such that the amplitude and phase characteristics on all signal paths from the multiple beamforming module match each other;
The multiple beam dispersion / combination apparatus for a mobile communication system according to claim 5, wherein: In a multiple beam dispersing / combining apparatus for a mobile communication system, wherein a base station has n sectors having m multiple beams for each sector,
A coupling module for combining said (nxm) beams to generate a traffic criterion signal for each sector;
A switch matrix module having (nxm) switch elements, each capable of combining each input to two sectors;
A terminating switch matrix module, having 2 × (n × m) terminating switch elements, each of which selects the output of said switch element or terminating load;
A combining module for combining all outputs from the termination switch matrix module for each sector;
A control unit that individually controls switching operations of the switch element and the terminal switch element based on the generated traffic determination reference signal;
A multiplex beam dispersion / combination apparatus for a mobile communication system, comprising: Each switch element sets a beam path to an original sector or another sector according to switching control of the control unit.
The multiple beam dispersion / combination apparatus for a mobile communication system according to claim 10, wherein: Each termination switch element is
Setting a beam path between the switch element and the combining module according to the switching control of the control unit, or terminating the input of the combining module;
The multiple beam dispersion / combination apparatus for a mobile communication system according to claim 10, wherein: 11. The mobile communication according to claim 10, wherein the terminal load is connected to block unnecessary noise inflow by blocking a beam path between the switch matrix module and the combining module. Multiple beam dispersion / combiner for the system. The apparatus of claim 10, wherein the combining module matches characteristics of a signal transmitted / received to / from the base station system.

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