WO2016031101A1

WO2016031101A1 - Radio base station apparatus, base station cell processing resource allocation method, and nontemporary computer readable medium on which program has been stored

Info

Publication number: WO2016031101A1
Application number: PCT/JP2015/002330
Authority: WO
Inventors: 俊樹竹内
Original assignee: 日本電気株式会社
Priority date: 2014-08-28
Filing date: 2015-05-07
Publication date: 2016-03-03
Also published as: JP6515931B2; JPWO2016031101A1

Abstract

Connection switch modules (31) to (3k) provided in a connection switching control unit (30) for switching the connections between baseband signal processing cards (21) to (2k) aggregated and accommodated in a baseband processing pool (20) and base station cells (11) to (1n) are configured such that each of the connection switch modules is connected to one or more adjacent ones thereof and such that the connection switch modules can be limitedly connected to that one or those ones of the adjacent baseband signal processing cards (21) to (2k) which are predetermined for each of the base station cells (11) to (1n). A processing resource allocating control unit (51) takes the limited connections into consideration and establishes, in advance, those candidates of the baseband signal processing cards (21) to (2k) the operations of which are to be set to off-states prior to the processing resource allocating control of the base station cells (11) to (1n).

Description

Non-transitory computer-readable medium storing radio base station apparatus, base station cell processing resource allocation method, and program

The present invention relates to a radio base station apparatus, a base station cell processing resource allocation method, and a base station cell processing resource allocation program. Particularly, in order to reduce the power consumption of the radio base station apparatus, the baseband signal processing unit (BB unit) for a plurality of base stations is aggregated, and the radio base station apparatus and base station cell efficiently share processing resources The present invention relates to a processing resource allocation method and a non-transitory computer-readable medium storing a base station cell processing resource allocation program.

Mobile data traffic is exploding due to the rapid spread of smartphones and tablet devices in recent years. In order to respond to future traffic explosions, the 3.5 GHz band as the 4G (4th Generation) frequency band, such as LTE (Long Term Evolution) -Advanced, at the 2007 World Radio Conference (WRC-07) As a result, international agreement has been obtained, and these new frequency bands are expected to be allocated for 4G. Also, as measures to increase the traffic capacity of the entire system, a heterogeneous network configuration in which multiple small cell base stations are installed in the area of the conventional macro cell base station, and high density installation of small cell base stations are being considered. ing.

Note that the traffic for each radio base station varies with time depending on the installation location. For example, in an office area, traffic peaks during the daytime, which is a working hour, while in a residential area, traffic peaks from evening to night after returning home. However, in any area, traffic decreases at midnight. Here, in the case of an existing wireless communication system, processing resources for wireless communication that are matched to the peak of each area are implemented for each base station. The processing resources for wireless communication of the base station operate independently of each other and consume power wastefully.

Therefore, in preparation for high-density installation of small cell base stations in the future to cope with traffic explosion, the processing resources of the radio communication processing unit such as baseband signal processing for a plurality of base stations are allocated within one radio base station apparatus. An architecture called C-RAN (Cloud Radio Access Network) or BB-Pooling (baseband pooling) has been proposed.

The concept of the C-RAN architecture is that the processing resources of the centralized wireless communication processing unit can be efficiently shared among multiple base stations, thereby reducing the cost and power consumption of the wireless base station device. Technology. That is, in the C-RAN architecture, the radio communication processing of a plurality of base stations is concentrated in one radio base station apparatus separately arranged as a master station, and ideally, traffic for all base station areas is collected. By implementing processing resources according to the peak in an averaged form, it is possible to reduce the size and cost of the apparatus. Also, resource sharing makes it possible to dramatically reduce the number of processing resources to be operated during low traffic, and to reduce power consumption.

Here, in order to efficiently realize the C-RAN architecture, a centralized computing unit (processing resource) is shared according to fluctuations in communication traffic of each base station, and the number of baseband cards to be operated and the number of computations are calculated. The overall architecture configuration technology and processing resource allocation technology that reduce the number of devices as much as possible are important issues. In addition, as another problem, it is also important to construct a highly scalable apparatus architecture that can gradually increase the radio base station apparatus with respect to gradually increasing traffic.

Regarding the overall architecture and processing resource allocation technology for the conventional radio base station apparatus, for example, Japanese Unexamined Patent Application Publication No. 2011-101104 “Radio Base Station Apparatus and Radio Base Station Apparatus Control Method” of Patent Document 1, No. 2012-257110, “Distributed antenna system, distributed antenna allocation method, base station apparatus”, Japanese Patent Laid-Open No. 2005-117579, “Radio transmission apparatus, radio reception apparatus, mobile communication system, and radio resource control method” in Patent Document 3. As disclosed in “BBU-RRH Switching Schemes for Centralized RAN” of Non-Patent Document 1 and “BBU-RRH Switching Method in Centralized RAN” of KDDI Laboratory of Non-Patent Document 2, etc. The prior art has been proposed.

For example, in the conventional technique disclosed in Patent Document 1 and the like, a technique for controlling the number of operating baseband cards in a radio base station apparatus has been proposed. That is, the radio base station apparatus includes a plurality of baseband cards, and includes a resource usage measurement unit and a control unit that performs resource accommodation switching of each baseband card based on the resource usage. ing. Further, the accommodation is changed in consideration of a card that can accommodate both the existing service and the HS (High Speed) service and a card that can accommodate only the existing service but cannot accommodate the HS service.

However, in the case of the conventional technique such as Patent Document 1, all the baseband cards and all the base station cell radio units are connected in all combinations (“number of baseband cards × number of base station radio cells”). It is premised that the number of combinations can be freely switched, and the circuit configuration of the connection switching unit is large and complicated. In addition, when trying to expand the baseband card or base station cell radio unit of the radio base station device, it is possible to connect to all of the other party even when extending one of them. It is necessary to replace the already installed connection switching unit with a new connection switching unit according to the number of baseband cards and the number of base station cell radio units, and the scalability is low. There is also.

Next, in the prior art disclosed in Non-Patent Document 1, etc., BBU (Base Band Unit: baseband signal processing card, ie, signal processing card for baseband signal) and RRH (Remote Radio Head: remote radio head, ie, Two types of switching methods have been proposed as switching methods to and from radio resources: a quasi-static switching method that tracks long-term traffic changes and a dynamic switching method that tracks short-term traffic changes. Yes.

However, the connection between the BBU and the RRH can be connected in all combinations using a switch, which is a premise of the two switching methods. Therefore, as in the case of the prior art such as Patent Document 1, it is necessary to provide a switch proportional to “the number of BBUs × the number of RRHs”. Accordingly, when the BBU is also increased, it is necessary to replace / expand the existing switch to a switch that takes into account the new number of BBUs and RRHs, and there is a problem that the expandability is low. That is, the extensibility of the BBU or RRH itself is taken into consideration, but the extensibility of the switch, that is, the connection switching unit is not considered.

In addition, if a switch that does not realize connection by all combinations is used, the desired utility cannot be obtained by the switching method proposed in Non-Patent Document 1 or the like. That is, there is a problem that a case where desired processing resource sharing cannot be realized occurs due to the inability to connect between all BBUs and RRHs.

In the prior art disclosed in Patent Document 2 and Patent Document 3 and the like, the connection state between a plurality of baseband units (BBU) and a plurality of radio resources (RRH), and BBU processing resources and user data There has been proposed a technique for switching the connection state between the switches using a switch or a buffer. In this case, the switch described in Patent Document 2 and the interconnection between the buffers described in Patent Document 3 are premised on that all combinations of connections can be realized. However, there is a problem that it is necessary to change the entire switch and the entire interconnection network between buffers.

JP2011-101104A (page 5-8) JP2012-257110A (pages 14-16) Japanese Patent Laying-Open No. 2005-117579 (pages 16-20)

The problems in the present invention will be described below. Generally, baseband signal processing for multiple base station cells (RRU: Remote Radio Unit remote radio unit) is aggregated into one or more baseband signal processing units (BBU: Base Band Unit baseband unit), and processing resources In a wireless base station apparatus that performs sharing, a connection that switches connection between BBU and RRU in order to efficiently share processing resources so that the number of active BBUs is reduced as much as possible in order to reduce power consumption. A switching unit is used.

The problem in the present invention is that when a connection switching unit capable of connecting all BBUs and all RRUs is mounted as in the prior art described above, a general switch or buffer interconnection network can be obtained. In the case of a simple connection switching unit, the circuit scale of the connection switching unit is proportional to “the number of BBUs × the number of RRUs”.

Also, when the RRU or BBU is increased in units of modules as traffic increases, the connection switching unit cannot be expanded linearly for the same reason. That is, the entire connection switching unit must be exchanged / changed in a non-linear manner depending on the number of existing BBUs and RRUs, and there is a problem that scalability is low.

On the other hand, if a connection switching unit that limits the combination of connections between BBU and RRU is used, in the processing resource allocation method proposed in the prior art, BBU and RRU When a combination that cannot be connected is generated, there arises a problem that a desired processing resource cannot be shared.

(Object of the present invention)
The present invention has been made in view of such circumstances, and connection switching for switching connections between a plurality of base station cells (RRU) and one or more aggregated baseband signal processing units (BBU). Even when the control unit uses a connection switching control unit that can be expanded linearly and can be expanded linearly in the same way as the RRU or BBU when the RRU or BBU is expanded, the BBU and the RRU A wireless base station apparatus, a base station cell processing resource allocation method, and a base station cell processing resource allocation method capable of obtaining an effect of reducing power consumption by processing resource sharing equivalent to the case of using a connection switching control unit realizing all connection combinations between It is an object to provide a base station cell processing resource allocation program.

In order to solve the above-described problems, the radio base station apparatus, the base station cell processing resource allocation method, and the base station cell processing resource allocation program according to the present invention mainly adopt the following characteristic configuration.

(1) A radio base station apparatus according to the present invention includes a baseband processing pool that aggregates and accommodates one or more baseband signal processing modules in a radio base station apparatus that aggregates radio communication processes for a plurality of base station cells. And a processing resource allocation control unit that allocates processing resources of each base station cell to each baseband signal processing module, and a connection that switches connection between the baseband signal processing module and the base station cell A switching control unit, and the connection switching control unit includes one or a plurality of connection switching modules, and each of the connection switching modules is adjacent to one another that is predetermined for each base station cell. In order to connect only to one of the baseband signal processing modules of A baseband signal processing module input / output interface connected to a subband signal processing module and a base station cell input / output interface connected to the base station cell, and between one or a plurality of adjacent connection switching modules. And an interconnection input / output interface for interconnecting the two.

(2) A base station cell processing resource allocation method according to the present invention is a base station cell processing resource allocation method in a radio base station apparatus that aggregates radio communication processing for a plurality of base station cells, and is aggregated in a baseband processing pool. As the baseband signal processing module that can be connected to each of the base station cells, one or a plurality of adjacent baseband signal processing modules that are predetermined for each base station cell are adjacent to each other. Each baseband signal processing module, and prior to the operation of performing processing resource allocation control for each base station cell for each baseband signal processing module, Baseband signal processing module that tries to set the operation to the off state. Characterized by preset candidates Lumpur.

(3) A base station cell processing resource allocation program according to the present invention is characterized in that the base station cell processing resource allocation method described in (2) is implemented as a program that can be executed by a computer. .

According to the radio base station apparatus, base station cell processing resource allocation method, and base station cell processing resource allocation program of the present invention, the following effects can be obtained.

The first effect is that, in a radio base station apparatus that consolidates radio communication processing for a plurality of base station cells (RRU), the circuit scale of the connection switching control unit is reduced, thereby reducing the apparatus size and power consumption. Can be realized.

The reason is that, in the radio base station apparatus of the present invention, as a connection switching control unit, a connection switching module that limits the connection between a base station cell (RRU) and a baseband signal processing module (baseband signal processing card: BBU). Are connected in series, so that the circuit is compared with the conventional connection switching unit that realizes all ideal connection combinations between the base station cell (RRU) and the baseband signal processing module (BBU). This is because the scale can be greatly reduced.

The second effect is that, in a radio base station apparatus that aggregates radio communication processing for a plurality of base station cells (RRU), in order to expand the apparatus in order to cope with traffic increase, the base station cell ( RRU) and baseband signal processing module (baseband signal processing card: BBU) as well as the connection switching module of the connection switching control unit can be linearly expanded as much as necessary. Is to improve.

The reason for this is that, in the radio base station apparatus of the present invention, the connection switching control unit limits the connection between the base station cell (RRU) and the baseband signal processing module (BBU) and Since a plurality of connection switching modules each having a connection interface are arranged side by side and connected to each other, the connection switching module is also expanded, for example, in the same manner as the base station cell (RRU) and the baseband signal processing module (BBU). This is because it may be expanded linearly according to “number”.

The third effect is that, in a radio base station apparatus that aggregates radio communication processes for a plurality of base station cells (RRU), even when a connection switching control unit with connection restrictions is used, ideal connection switching is performed. Processing resources can be shared in the same manner as in the case of using a part, and the power consumption can be reduced to the same level.

This is because, in the base station cell processing resource allocation method of the present invention, a baseband signal processing module (BBU) to be turned off (to be set to turn off) is determined in advance, and the operation OFF target For example, the baseband signal processing module (BBU) that is distant from the baseband signal processing module (BBU) that is the target of operation OFF is prioritized in order from the baseband signal processing module (BBU) information. In this way, the processing resource allocation control is performed for the baseband signal processing module (BBU) in the operation ON state.

It is a block block diagram which shows the example of whole structure of the wireless base station apparatus in the 1st Embodiment of this invention. It is a schematic diagram which shows the structural example of the connection switching module in the 1st Embodiment of this invention. It is a connection block diagram which shows the connection structural example of the connection switching module in the 1st Embodiment of this invention. It is a control flowchart for demonstrating an example of the whole process sequence regarding the processing resource allocation control in the 1st Embodiment of this invention. It is explanatory drawing for demonstrating an example of the mechanism which determines the order of the baseband signal processing card | curd (BBU) which wants to make operation OFF next in the processing resource allocation control in the 1st Embodiment of this invention. An example of processing for moving a base station cell (RRU) process of a baseband signal processing card (BBU) to another baseband signal processing card (BBU) in the processing resource allocation control according to the first embodiment of the present invention is shown. It is a control flowchart. It is a control flowchart which shows an example of the process which allocates the undetermined base station cell (RRU) process with respect to a baseband signal processing card | curd (BBU) in the processing resource allocation control in the 1st Embodiment of this invention. It is a block block diagram which shows the example of whole structure of the wireless base station apparatus in the 2nd Embodiment of this invention. It is a schematic diagram which shows the structural example of the connection switching module in the 2nd Embodiment of this invention. It is explanatory drawing for demonstrating the connection structural example of the connection switching module in the 2nd Embodiment of this invention, and an example of the mechanism which determines the order of the baseband signal processing card | curd (BBU) which wants to make operation OFF next. is there. It is a block block diagram which shows the example of whole structure of the wireless base station apparatus in the 3rd Embodiment of this invention. For explaining problems in the case of using an ideal connection switching unit such as a crossbar type that realizes all connection combinations between a conventional base station cell (RRU) and a baseband signal processing card (BBU) It is explanatory drawing. It is a schematic diagram for demonstrating the processing resource sharing effect of the base station cell processing resource allocation method in Embodiment of this invention, and the conventional base station cell processing resource allocation method.

Hereinafter, preferred embodiments of a radio base station apparatus, a base station cell processing resource allocation method, and a base station cell processing resource allocation program according to the present invention will be described with reference to the accompanying drawings. In the following description, a radio base station apparatus and a base station cell processing resource allocation method according to the present invention will be described. As a base station cell processing resource allocation program that can be executed by a computer, the base station cell processing resource allocation method is executed. Needless to say, the base station cell processing resource allocation program may be recorded on a computer-readable recording medium. In addition, it is needless to say that the drawing reference numerals attached to the following drawings are added for convenience to the respective elements as an example for facilitating understanding, and are not intended to limit the present invention to the illustrated embodiments. Yes.

(Features of the present invention)
Prior to the description of the embodiments of the present invention, an outline of the features of the present invention will be described first. The present invention provides one or a plurality of baseband signal processing modules (BBU: Base Band Unit base) in which baseband signal processing (radio communication processing) for a plurality of base station cells (RRU: Remote Radio Unit) is integrated. In a radio base station device that performs processing switching by using a band signal processing card), as a connection switching unit arranged to perform connection switching between RRU and BBU, when RRU or BBU is expanded, Similar to RRU and BBU, even when a connection switching unit that can be realized with a relatively simple circuit configuration that can be linearly expanded and linearly expands is used, BBU and RRU When using a conventional connection switching unit that realizes connection of all combinations so that combinations that cannot be connected between the two will not occur The main feature is that the same level of power consumption can be achieved by sharing processing resources.

More specifically, the present invention has the following mechanism. That is, in a radio base station apparatus that performs baseband signal processing (wireless communication processing) for a plurality of base station cells (RRU) in a baseband signal processing module (BBU), the connection between the RRU and the BBU A connection switching control unit that performs switching, and the connection switching control unit includes a configuration in which one or a plurality of connection switching modules that can be connected only to three or more adjacent BBUs are arranged and connected to each other The main feature is to do.

At the same time, considering the limited connection state as described above, it is desirable to turn off the operation (ie, to set the operation to the off state) prior to the operation of assigning the RRU processing resource to the BBU. The main feature is that candidates are determined in advance, and thereafter, processing resource allocation control is performed preferentially in order from a BBU that is distant from the determined BBU candidate.

When the processing resource usage rate of the BBU that has been preferentially assigned processing exceeds a predetermined upper limit value, the RRU processing related to the RRU at a position away from the BBU is prioritized in order. On the other hand, if the processing resource usage rate of the BBU falls below a predetermined lower limit value, on the contrary, the RRU related to the RRU that is close to the connection distance from the BBU. It is also a main feature that processing allocation control for the BBU is performed with priority in order from processing.

Thus, according to the present invention, the following effects can be obtained. The radio base station apparatus according to the present invention has a configuration in which connection switching modules connectable to only three or a plurality of adjacent BBUs are arranged as a connection switching control unit, thereby extending RRU or BBU. As with the RRU and BBU, it is possible to cope with only by linearly expanding the connection switching module, and it is possible to realize a radio base station apparatus that can be linearly expanded including the connection switching control unit. .

Then, while limiting the combination of connections between the BBU and the RRU, considering the constraint conditions, the BBU to be turned off is determined in advance, and from the BBU that is distant from the determined BBU Ideal connection switching with no limitation on connection by performing process allocation control in order, and by adopting a process allocation control method that considers the connection distance from the target BBU for the RRU process allocation control for the target BBU. Sharing of processing resources, that is, low power consumption can be realized, which is almost equivalent to the case of using a unit.

(Embodiment of the present invention)
Next, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 11. First, in the first embodiment, as an example of a radio base station apparatus according to the present invention, baseband signal processing (radio communication processing) for a plurality of base station cells (RRU: Remote Radio Unit) is 1 Or, in a radio base station apparatus that aggregates into a plurality of baseband signal processing modules (BBU: Base Band Unit baseband signal processing card) and shares processing resources, to switch connection between RRU and BBU Next, the basic configuration and characteristics of the connection switching control unit arranged in the radio base station apparatus and the operation and characteristics of the base station cell processing resource allocation method will be described in detail. In the second embodiment, a configuration example of a radio base station apparatus including a connection switching module that can be connected to five (a plurality) of adjacent baseband signal processing modules (BBUs) as a connection switching control unit. It explains in detail about. Furthermore, in the third embodiment, a configuration example of a radio base station apparatus in which a baseband signal processing module, a base station cell, and a connection switching module are clustered in a predetermined unit will be described in detail.

(Configuration example of the first embodiment)
FIG. 1 is a block configuration diagram showing an example of the overall configuration of the radio base station apparatus according to the first embodiment of the present invention. As the radio base station apparatus, radio signal processing is aggregated and radio resources that share processing resources are shared. The example of whole structure of the base station apparatus is shown.

A radio base station apparatus 100 shown in FIG. 1 is a baseband processing pool that aggregates and executes radio communication processes of n (n: natural number) base station cells (RRU: Remote Radio Unit remote radio units) 11 to 1n. (BBU-pool) 20 and k (k: natural number, k ≦ n) baseband signal processing cards (BBU: Base Band Unit baseband signal processing module) in the baseband processing pool (BBU-pool) 20 ) 21 to 2k. Each of the k (one or plural) baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 20 is connected between n base station cells (RRU) 11 to 1n. While sharing the processing resources, for example, wireless Layer-1 processing (baseband signal processing) such as LTE-Advanced is performed.

In addition, the RF (Radio Frequency) unit side of each of the k (one or plural) baseband signal processing cards (BBUs) 21 to 2k is connected to the optical fiber or wireless back via the connection switching control unit 30. The base station cells (RRU) 11 to 1n are connected by holes (front holes) or the like. Here, there is no problem even if the radio system to be processed in the baseband processing pool (BBU-pool) 20 is a radio system other than LTE-Advanced, and the layer to be processed is a Layer- other than Layer-1. There is no particular problem even if the second processing is performed.

The connection switching control unit 30 includes k connection switching modules 31 to 3k corresponding to each of the k (one or plural) baseband signal processing cards (BBU) 21 to 2k, and includes k pieces. Each of the connection switching modules 31 to 3k is arranged in order, and the adjacent ones are connected to each other. Here, each of the connection switching modules 31 to 3k is connected to one or more base station cells (RRU) 11 to 1n and one or more baseband signal processing cards (BBU) 21 to 2k, respectively. And a connection between adjacent connection switching modules is possible. For example, of the k connection switching modules 31 to 3k, the i-th (1 ≦ i ≦ k) -th connection switching module 3i is adjacent to the (i−1) -th connection switching module 3 (i−1). It is also possible to connect to the (i + 1) th connection switching module 3 (i + 1).

Therefore, of the n base station cells (RRU) 11 to 1n, any base station cell (RRU) connected to the i-th connection switching module 3i, for example, the j-th (1 ≦ j ≦ n) -th base The station cell (RRU) 1j is centered on the i-th BBU 2i corresponding to the connection switching module 3i to which the RRU 1j is connected, and is located between a plurality of adjacent BBUs on both sides, that is, the (i−1) -th BBU 2 ( It is possible to switch the connection between i−1) and the (i + 1) th BBU2 (i + 1).

Also, the radio base station apparatus 100 includes a processing resource allocation control unit 51 for processing resource allocation control for k baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 20. A traffic prediction unit 52 and a connection information storage unit 53 are also provided.

The traffic prediction unit 52 is a part that predicts traffic in the next certain period using a past traffic history, database, or the like for processing resource allocation control. Based on the traffic predicted by the traffic prediction unit 52, the processing resource allocation control unit 51 sets each of the k baseband signal processing cards (BBUs) 21 to 2k of the n base station cells (RRU) 11 to 1n. This is a part that performs processing resource allocation control for. The connection information storage unit 53 stores which RRU and which BBU as connection information between the base station cells (RRU) 11 to 1n and the baseband signal processing cards (BBU) 21 to 2k to which limited connection is performed. Is stored, and the processing resource allocation control unit 51 refers to the connection information in the connection information storage unit 53 as necessary to perform processing resource allocation control. .

(Description of the operation of the first embodiment)
Next, an example of the operation of the radio return station apparatus 100 shown in FIG. 1 as the first embodiment of the present invention will be described in detail with reference to FIGS. In each of the k baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 20 of the radio base station apparatus 100 shown in FIG. Wireless communication processing such as Layer-1 processing (baseband signal processing) such as LTE-Advanced, for example, is performed collectively for the base station cells (RRU) 11 to 1n.

By sharing processing resources among the k baseband signal processing cards (BBU) 21 to 2k, each base station cell (RRU) for the base station cells (RRU) 11 to 1n can be processed with k baseband signals. Among the processing cards (BBUs) 21 to 2k, in order to change which baseband signal processing card (BBU) is used, each base station cell (RRU) 11 to 1n and each baseband signal processing card (BBU) The connection switching between 21 and 2k is performed by the connection switching control unit 30. Each transmission / reception signal switched by the connection switching control unit 30 is connected to the base station cells (RRU) 11 to 1n that are connected to each other via an optical fiber or a wireless backhaul (fronthaul). It is transmitted / received to / from the band signal processing card (BBU) 21-2k.

Here, the connection switching control unit 30 is configured such that adjacent connection switching modules 31 to 3k are connected to each other so that adjacent connection switching modules can be interconnected. FIG. 2 is a schematic diagram showing a configuration example of the connection switching modules 31 to 3k according to the first embodiment of the present invention. As a configuration example of each of the connection switching modules 31 to 3k, the i-th (1 ≦ i Taking a connection switching module 3i of ≦ k) as an example, a configuration example is shown that enables interconnection with one connection switching module on each side.

In the example shown in FIG. 2, one connection switching module 3 i is connected to one of BBU # i, an input / output interface for a baseband signal processing module (BBU), (at least) RRU # j ₁ , RRU #J ₂ , RRU # j ₃ (1 ≦ j ₁ , j ₂ , j ₃ ≦ k) Baseband signal processing module (BBU) base station cell (RRU) input / output for connection between three RRUs An example in which an interface and an input / output interface for interconnection for interconnecting the connection switching module 3 (i-1) and the connection switching module 3 (i + 1) adjacent to each other are provided is shown. For example, no matter how large the traffic is due to only one of the i-th BBU # i connected to the connection switching module 3i, (at least) any three RRUs, for example j ₁ th RRU # _{j 1,} the _{j 2} th RRU # _{j 2,} the wireless communication processes on three RRU of the _{j 3}

th

_{_{RRU # j 3 (1 ≦ j}} 1, j 2, j 3 ≦ k) A configuration example assuming a case where it can be performed is shown.

In the case of the configuration example shown in FIG. 2, the first RRU input interface 1 from the _three RRU # j ₁ , RRU # j ₂ , and RRU # j ₃ connected to the connection switching module 3 i is one system, adjacent connection on both sides switching module 3 (i-1) and 3 (i + 1) first 2RRU input interface 2 two systems _{_{from, RRU # j 1, RRU #}} j 2, RRU # j 3 sides of adjacent connection from the switching module 3 (i-1 ) And 3 (i + 1) are two first RRU output interfaces 3 and a selection circuit for selecting and arbitrating each input from each of the first RRU input interface 1 and the second RRU input interface 2 (FIG. (Not shown).

In the embodiment shown in FIG. 2, a maximum of nine base station cells (RRU) per BBU, for example, BBU # i, depending on the maximum processing capability of each baseband signal processing card (BBU) 21-2k. Can be connected and processed. FIG. 2 shows only the signal flow from the RRU side to the BBU side, and the description of the reverse signal flow from the BBU side to the RRU side is omitted. However, it should be noted that in reality, there is almost the same reverse signal flow from the BBU side to the RRU side.

In this way, a plurality of connection switching modules are arranged side by side and connected to each other and interconnected with one connection switching module on each of the adjacent sides, so that any connection switching module such as connection switching module #i 3i can be connected. base station cell (remote RF unit) for example remote RF unit # _{j 1} is about the BBU example BBU # i the remote RF unit # _{j 1} corresponding to the connected connection switching module for instance connected switching modules #i 3i, at least, multiple adjacent It is possible to switch the connection between the three BBUs (three in the example of FIG. 2), for example, BBU # (i−1), BBU # i, and BBU # (i + 1).

FIG. 3 is a connection configuration diagram showing a connection configuration example of the connection switching modules 31 to 3k in the first embodiment of the present invention, and each of the k connection switching modules 31 to 3k shown in FIG. An example of a connection configuration between RRU and BBU in the case of using the connection switching module illustrated in FIG. In the embodiment of FIG. 3, the number k of connection switching modules 31 to 3k and baseband signal processing cards (BBU) 21 to 2k is four (k = 4), and the number n of base station cells (RRU) 11 to 1n is n. Shows the case of twelve (n = 12).

Also, each of the BBU # 1 to BBU # 4 basically (assuming a case where traffic is large), and each of the connection switching modules # 1 to # 4 corresponding to each of the BBU # 1 to BBU # 4. The case where the process regarding three RRUs connected to each is performed is shown. That is, BBU # 1 has three RRUs RRU # 1 to RRU # 3, BBU # 2 has three RRUs RRU # 4 to RRU # 6, and BBU # 3 has RRU # 7 to RRU. The # 9 RRUs and BBUs # 4 perform RRUs for RRU # 10 to RRU # 12, respectively.

Then, each of the RRU # 1 to RRU # 12 is an adjacent BBU that is predetermined for each RRU # 1 to RRU # 12 among the BBU # 1 to BBU # 4 of the baseband processing pool (BBU-pool) 20. It is possible to connect only to any of the above. That is, each of RRU # 1 to RRU # 12 is centered on each of BBU # 1 to BBU # 4 connected corresponding to each of connection switching module # 1 to connection switching module # 4 to which each RRU is connected. It is possible to selectively connect to any of a total of three BBUs including at least two BBUs adjacent to both sides. For example, in the case of RRU # 4 in FIG. 3, it is connected to the connection switching module # 2, but the BBU # 1 and BBU # 3 adjacent to both sides are centered on the correspondingly connected BBU # 2. Any of the three BBUs (BBU # 1, BBU # 2, BBU # 3) can be selected and connected.

For example, when traffic is small, an arbitrary BBU, for example, BBU # 2, out of the four BBU # 1 to BBU # 4, is centered on the connection switching module # 2 to which the BBU # 2 is connected correspondingly. 9 connected to three connection switching modules (connection switching module # 1, connection switching module # 2, connection switching module # 3) including adjacent connection switching module # 1 and connection switching module # 3 The RRU can be connected and processed.

That is, for example, in the case of BBU # 2, three of RRU # 4 to RRU # 6 connected to the BBU # 2, and each of the connection switching module # 1 and the connection switching module # 3 adjacent to each other It is possible to connect and process a maximum of nine RRU # 1 to RRU # 3, which is a total of three RRU # 1 to RRU # 3 and three RRU # 7 to RRU # 9. is there.

Next, as illustrated in FIG. 1, the radio base station apparatus 100 performs k resource sharing based on the traffic prediction result by the traffic prediction unit 52 (traffic prediction function) in order to share processing resources in each BBU. A processing resource allocation control unit 51 that allocates processing resources of n base station cells (RRU) 11 to 1n to the baseband signal processing cards (BBU) 21 to 2k is provided.

The traffic prediction unit 52 includes a traffic database (average value of daily traffic for each time interval) in which daily traffic data is accumulated at a certain predetermined time interval, traffic history of each day (each time The traffic prediction for the next certain time interval is performed for each of the n base station cells (RRU) 11 to 1n using the actual traffic value of the current day for each interval).

Further, the processing resource allocation control unit 51, based on the traffic predicted by the traffic prediction unit 52, n base station cells (RRU) for each of the k baseband signal processing cards (BBUs) 21 to 2k. 11 to 1n processing resource allocation is controlled. The purpose of the processing resource allocation control is to increase the number of BBUs that can be turned off as much as possible by operating only as few BBUs as possible by sharing processing resources in order to realize low power consumption.

Next, an example of a control method for base station cell processing resource allocation performed in the processing resource allocation control unit 51 to realize low power consumption will be described with reference to the control flowcharts of FIGS. 4, 6, and 7 and FIG. This will be described with reference to FIG. FIG. 4 is a control flowchart for explaining an example of the entire processing procedure related to processing resource allocation control according to the first embodiment of the present invention.

In the processing resource allocation control according to the first embodiment of the present invention, as shown in the control flowchart of FIG. 4, first, the traffic prediction result by the traffic prediction unit 52 and each of the k baseband signals at the current point. From the operating state of the processing card (BBU) 21 to 2k, the processing resource allocation control unit 51 next sets the baseband signal processing card (BBU) that wants to turn off the operation (that is, to set the operation to the off state). The order is determined in advance (step S1). Once the order of the baseband signal processing cards (BBU) to be turned off is determined, the order of the baseband signal processing cards (BBU) that performs processing resource allocation control is also determined in advance (step S2). For example, priority is given to the baseband signal processing card (BBU) that is distant from the baseband signal processing card (BBU) that is next desired to be turned off as the order of the baseband signal processing card (BBU) that performs processing resource allocation control. Set to.

Here, the reason for performing steps S1 and S2 is that, in the first embodiment of the present invention, in order to improve the expandability of radio base station apparatus 100, a base station cell (RRU) -baseband signal Since the connection switching control unit 30 that limits a part of the connection between the processing cards (BBU) is used, processing resources are allocated to BBUs that cannot be connected from a specific RRU. This is because it is necessary to prevent this in advance.

FIG. 5 shows the baseband signal processing cards (BBU) 21 to 2k that are to be turned off next (that is, the operation is to be set to the off state) in the processing resource allocation control in the first embodiment of the present invention. FIG. 5 is an explanatory diagram for explaining an example of a mechanism for determining the order, but details of the process of step S1 in the control flowchart of FIG. 4 (the determination method of the baseband signal processing card (BBU) to be turned off next). An example of the detailed mechanism of not only the mechanism but also the process of step S2 (a method of determining a baseband signal processing card (BBU) that performs processing resource allocation control) is described. In the explanatory diagram of FIG. 5, the number of baseband signal processing cards (BBU) in the baseband processing pool (BBU-pool) 20 is eight, BBU # 1 to BBU # 8, and the corresponding connection switching control unit. The number of 30 connection switching modules is also 8 of connection switching module # 1 to connection switching module # 8, while the number of base station cells (RRU) of base station cell radio unit (RRU) 10 is set to RRU # 1 to RRU # 1. The case where the number of RRU # 24 is 24 is illustrated.

In the process of step S1 (the determination method of the baseband signal processing card (BBU) to be turned off next time), the processing resource allocation control unit 51 performs basic processing according to the traffic amount predicted by the traffic prediction unit 52. The baseband signal processing card (BBU) that wants to turn off the operation (that is, to set the operation to the off state) is set at every power-of-two interval.

That is, for example, as shown in FIG. 5A, when the traffic is large, BBUs to be turned off are set at intervals of 8 (= 2 ³ ) (in the case of the example of FIG. 5, For example, one BBU of BBU # 4 is set out of the eight BBUs). Further, as shown in FIG. 5 (B), in the case of moderate traffic, with four (= 2 ²⁾ interval, sets the BBU to be in the operation OFF (in the example of FIG. 5, Among the eight BBUs, for example, two BBUs of BBU # 4 and BBU # 8 are set). Further, as shown in FIG. 5C, when traffic is small, BBUs to be turned off are set at intervals of 2 (= 2 ¹ ) (in the example of FIG. 5, 8). For example, four BBUs of BBU # 2, BBU # 4, BBU # 6, and BBU # 8 are set.

Further, as the operation state of each baseband signal processing card (BBU) at the time of traffic prediction, the BBU operation state (for example, BBU # 4 or other of 8 BBUs) described in “Traffic large” in FIG. If any one of the BBUs is in an operation OFF state, then the BBU operating state described in “traffic” in FIG. 5B (for example, BBU # 4 out of 8 BBUs) , A process resource allocation control is performed aiming at a state where any other two BBUs are turned off at intervals of two or four of BBU # 8. That is, for example, as shown in FIG. 5A, when one BBU of BBU # 4 is in an operation OFF state, as shown in “Low” in FIG. In addition, it aims to turn off the operation of BBU IV # 8.

If the BBU operating state “in traffic” of FIG. 5B has already been realized as the operating state of the baseband signal processing card (BBU) at the time of traffic prediction, next, FIG. BBU operating state described in “Small traffic” (e.g., out of 8 BBUs, for example, BBU # 2, BBU # 4, BBU # 6, BBU # 8, or any other 4 BBUs at intervals of 2) The processing resource allocation control is performed aiming at a state where the operation is turned off. That is, for example, as shown in FIG. 5B, when two BBUs BBU # 4 and # 8 are in an operation OFF state, as shown in “Low” in FIG. In addition, it aims to turn off operation of BBU # 2 and # 6 in addition.

Next, the mechanism of the process of step S2 (a method for determining a baseband signal processing card (BBU) that performs processing resource allocation control) will be described with reference to FIG. The processing resource allocation control unit 51 selects a baseband signal processing card (BBU) that performs processing resource allocation control as far as possible from a BBU that is to be turned off (including BBUs that are already turned off). Processing resource allocation control is performed with priority in order. Here, when there are a plurality of BBUs that are desired to be turned off (that is, the operation is to be set to the off state) and BBUs that are already in the operation OFF state, processing resources are sequentially processed from the BBU located in the middle of the corresponding BBU. Perform allocation control.

For example, the traffic prediction unit 52 predicts that the traffic is large, and for example, BBU # 4 is determined as the BBU to be next turned off among the 8 BBUs, as described in “traffic large” in FIG. If BBU # 4 has already been set to the operation OFF state, as shown in “High1” in FIG. 5A, the BBU that is farthest from the BBU # 4 in distance Processing resource allocation control is performed preferentially from # 8. Further, as described in “traffic” in FIG. 5B, for example, BBU # 4 and BBU # 8 among the eight BBUs are set as BBUs to be next turned off, as traffic is predicted to be medium. If determined, or if BBU # 4 and BBU # 8 have already been set to the operation OFF state, as shown in “High1” in FIG. 5B, the BBU # 4 and BBU # The processing resource allocation control is preferentially performed in order from the BBU # 2 or # 6 that is the BBU located farthest from the distance 8, that is, between the BBU # 4 and the BBU # 8.

Note that, as described in “traffic” in FIG. 5B, when there are a plurality of BBUs to be turned off and BBUs that are already turned off, the BBUs that are separated by the same distance from the plurality of BBUs. When there are a plurality of BBUs, the processing resource allocation control may be preferentially performed in order from any BBU among a plurality of BBUs separated by the same degree. In the case of “large traffic” in FIG. 5A, BBU # 1 and BBU # 7 have a distance from BBU # 4 as BBUs that preferentially process resource allocation control next to BBU # 8. In the case of the same degree, either BBU # 1 or BBU # 7 may be selected as the next priority order of BBU # 8.

Next, returning to the description of the control flowchart of FIG. 4, each step after step S3 will be described. As shown in the control flowchart of FIG. 4, according to the control order of the BBU processing resource allocation control determined in step S2, threshold determination regarding the processing resource usage rate as described below is performed in order from the BBU having the highest priority order. Repeat the process. First, with respect to the target BBUs selected in order, the processing resource usage rate is calculated from the traffic predicted values of all the RRUs allocated at the present time, and a threshold value determination with a threshold value A that is a predetermined upper limit value is performed (step S3). . If the processing resource usage rate of the target BBU exceeds the threshold value A, which is the upper limit (Yes in step S3), there is a concern that processing resources will be insufficient, and therefore allocation control will be described in detail in FIG. Process A (proc.A) is executed (step S5), and it is determined whether or not any RRU process already assigned to the target BBU can be moved to another BBU. If it is determined that the process is possible, the process of moving the RRU process to another BBU determined to be processable is executed.

If the processing resource usage rate of the target BBU does not exceed the threshold value A that is the upper limit value (No in step S3), next, a threshold value determination with the threshold value B that is a predetermined lower limit value is performed ( Step S4). If the processing resource usage rate of the target BBU is below the threshold value B, which is the lower limit (Yes in step S4), there is still a processing capacity margin that can execute another RRU process on the target BBU. Therefore, the allocation control process B (proc.B) described in detail in FIG. 7 to be described later is executed (step S6), and the RRU process is allocated to a BBU other than the target BBU. For the RRU process for which the current allocation has not yet been determined, it is determined whether or not the target BBU can be processed, and if it is determined that the process is possible, the process of allocating the corresponding RRU process to the target BBU Execute.

In the control flowchart of FIG. 4, the threshold value determination process relating to the processing resource usage rate of the BBU, the allocation control process A (proc.A), and the allocation control process B (proc.B) shown in steps S3 to S6 are performed. When all BBUs are repeatedly performed in order in the BBU order determined in step S2, and processing resource allocation is determined for all BBUs, one processing resource allocation control is completed.

Next, details of the above-described allocation control process A (proc. A) will be described using the control flowchart of FIG. FIG. 6 shows a process of moving the base station cell (RRU) process of the baseband signal processing card (BBU) to another baseband signal processing card (BBU) in the processing resource allocation control according to the first embodiment of the present invention. FIG. 4 is a control flowchart showing an example of the RRU process assigned to the target BBU when the processing resource usage rate of the target BBU exceeds a threshold value A that is a predetermined upper limit value. Among these, an example of the processing content of the allocation control processing A (proc. A) for moving any RRU processing to another BBU is shown.

In the control flowchart shown in FIG. 6, first, in order to prevent the RRU processing resource allocation control related to the RRU to the BBU that cannot be connected from any RRU by the limited connection function of the connection switching control unit 30, the target BBU Among the assigned RRUs, the priority order of RRUs that are candidates for moving the RRU process is determined (step A1). Here, the priority order of the RRUs that are candidates for moving the RRU process is, for example, from the target BBU based on the RRU-BBU connection information stored in the connection information storage unit 53 shown in FIG. Are set in order of priority from the RRU having a long connection distance. Then, according to the priority order determined in step A1, the following RRU process allocation control is repeated until the processing resource usage rate of the target BBU falls below the threshold value A which is the upper limit value.

First, regarding the RRUs selected according to the priority order, it is determined whether or not the RRU process can be assigned to the BBUs already operating in the vicinity of the RRU as the BBUs to which the RRU can be connected (step A2). When the RRU process can be assigned to the active BBU around the RRU, that is, even if the RRU process is newly assigned to the active BBU, the resource usage rate of the active BBU does not exceed the upper limit threshold A. In such a case (Yes in step A2), the RRU process is moved to the active BBU around the RRU (step A6).

On the other hand, when it is impossible to allocate the RRU process to the active BBU around the RRU (No in Step A2), the RRU is connected as a connectable BBU, and the operation is turned off at that time around the RRU. It is determined whether or not the relevant RRU process can be assigned to the BBU that is now (step A3). When the RRU process assignment can be performed for the BBU in the operation OFF state around the RRU (Yes in Step A3), the RRU process is moved to the BBU in the operation OFF state around the RRU (that is, the BBU is moved). The operation is turned on) (step A7).

On the other hand, when the process allocation is impossible for both the BBU in the operation OFF state and the active BBU around the RRU (No in step A3), among the connectable BBUs for which the process allocation has not yet been determined, Even if the processing resource usage rate exceeds the upper limit threshold A, the RRU process is moved to the BBU located closest to the RRU (step A4). Here, the process of step A4 is a process for preventing the allocation of process resources to BBUs that cannot be connected from any RRU.

After performing the movement process of Steps A4, A6, and A7, the processing resource usage status of the target BBU as a result of moving the RRU process that was a movement candidate to any BBU that can be assigned the RRU process Therefore, the threshold value determination process for comparing the processing resource usage rate of the target BBU with the threshold value A which is a predetermined upper limit value is performed again (step A5). When the processing resource usage rate of the target BBU still exceeds the upper limit threshold A (No in step A5), according to the priority order determined in step A1, other RRUs in the next priority order Steps A2 to A4, A6, and A7 are repeated.

On the other hand, when the processing resource usage rate of the target BBU is equal to or less than the threshold A (Yes in Step A5), the processing resource allocation for the RRU process is determined for the target BBU (Step A8), and the target BBU is determined. Complete the processing resource allocation control.

Next, details of the above-described allocation control process B (proc. B) will be described using the control flowchart of FIG. FIG. 7 is a control flowchart showing an example of processing for allocating undecided base station cell (RRU) processing to a baseband signal processing card (BBU) in processing resource allocation control according to the first embodiment of the present invention. As shown in FIG. 4, when the processing resource usage rate of the target BBU is below the threshold value B that is a predetermined lower limit value, the process allocation for the BBU including the target BBU is still undecided. It is determined whether or not the RRU process can be allocated to the target BBU. If the allocation is possible, an example of the processing content of the allocation control process B (proc. B) that allocates the RRU process to the target BBU Show.

In the control flowchart shown in FIG. 7, first, similarly to the case of FIG. 6, the processing resource allocation control of the RRU processing related to the RRU to the BBU that cannot be connected from any RRU by the limited connection function of the connection switching control unit 30. In order to prevent this, among the RRU processes for which the process allocation for the BBU has not yet been determined including the target BBU, the priority order of the RRUs that are candidates for the RRU process allocation is determined (step B1). Here, the priority order of RRUs that are candidates for allocation of RRU processing is determined based on, for example, the connection information between the RRU and the BBU stored in the connection information storage unit 53 shown in FIG. The priority is set in the order of priority from the RRU with the connection distance close. Then, according to the priority order determined in step B1, the following RRU process allocation control is repeated until the processing resource usage rate of the target BBU exceeds the threshold value B, which is the lower limit value.

First, with respect to the RRU selected according to the priority order, it is determined whether or not the relevant RRU process can be assigned to the target BBU to which the RRU can be connected (step B2). If the target RBU process can be assigned to the target BBU, that is, even if the target BBU is newly assigned, the resource usage rate of the target BBU does not exceed the upper threshold value A (step) (Yes in B2), the RRU process is moved to the target BBU, and the RRU process is assigned to the target BBU (step B3).

Here, even if the RRU process is moved and assigned to the target BBU, if the resource usage rate of the target BBU has not yet reached the threshold B that is the lower limit value (No in step B4), or If the resource usage rate of the target BBU exceeds the upper limit threshold A in step B2 and the RRU process cannot be allocated to the target BBU (No in step B2), the priority determined in step B1 Accordingly, the processes of steps B2 to B4 are repeated for the other RRUs in the next priority order.

On the other hand, when the RRU process is moved to the target BBU, when the resource usage rate of the target BBU becomes equal to or higher than the threshold B that is the lower limit (No in Step B4), or processing resource allocation control is performed for all candidate RRUs Is completed, the RRU processing resource allocation for the target BBU is determined (step B5), and the processing resource allocation control for the target BBU is completed.

As described in detail above, in the first embodiment of the present invention, the connection switching control unit 30 that performs connection switching control between RRU and BBU has an interconnection interface between adjacent connection switching modules. One or a plurality of connection switching modules 31 to 3k are arranged so that the connection relationship from the RRU is not all baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 20, By limiting to only adjacent BBUs, it is possible to prevent the circuit scale of the connection switching control unit 30 from increasing.

In other words, in the case of an ideal connection switching control unit that realizes all connection combinations between RRU and BBU, the connection switching control unit requires a scale proportional to the multiplication of the respective numbers of “RRU number × BBU number”. It becomes. On the other hand, in the first embodiment of the present invention, the scale of the connection switching control unit 30 is limited to a scale proportional to “the number of connected RRUs (9 in the example shown in FIG. 2) × the number of BBUs”. Thus, the connection switching control unit can be suppressed to a circuit scale almost linear with the number of BBUs. Therefore, in the first embodiment of the present invention, when the RRU or BBU is increased as the traffic increases, the connection switching module can be expanded almost linearly according to the number of BBUs. Thus, an advantage that high expandability can be secured is obtained.

Further, in order to improve expandability, even in the configuration in which the connection relationship between RRU and BBU is limited as described above, in the first embodiment of the present invention, it is desired to turn off the operation (that is, the operation Base station cell processing resources that predetermine BBUs and perform processing resource allocation control in order from the BBU located far away from the BBU that is the target of operation OFF. An allocation method is adopted. Further, in the first embodiment of the present invention, when the processing resource usage rate of the target BBU exceeds a predetermined upper limit threshold A, the RRUs in order from the RRU at a position away from the target BBU. If the processing resource usage rate of the target BBU falls below a predetermined lower limit threshold B, the connection distance is close to the target BBU. A base station cell processing resource allocation method is adopted in which transfer control of RRU processing is preferentially performed in order from a certain RRU.

Thus, even if the connection relationship between RRU and BBU is limited, it is almost equivalent to the case of using an ideal connection switching control unit that can connect RRU and BBU with all connection combinations. It is possible to realize the processing resource sharing (as well as the reduction in power consumption). This is because the base station cell processing resource allocation method according to the first embodiment of the present invention employs a mechanism for allocating RRU processing resources in order from an RRU having a connection distance as close as possible to an arbitrary BBU. This is because a mechanism capable of preventing a situation in which RRU processing related to an arbitrary RRU is assigned to a BBU having no connection relationship is realized.

(Configuration example of the second embodiment)
Next, a configuration example of the radio base station apparatus according to the second embodiment of the present invention will be described with reference to FIG. FIG. 8 is a block configuration diagram illustrating an example of the overall configuration of the radio base station apparatus according to the second embodiment of the present invention. As the radio base station apparatus, as in the case of FIG. 1 of the first embodiment, An example of the overall configuration of a radio base station apparatus that consolidates radio signal processing and shares its processing resources is shown. However, in the radio base station apparatus 101 shown in FIG. 8 of the second embodiment, each connection switching module 41 differs from the configuration of the connection switching control unit 30 in the case of FIG. 1 of the first embodiment. ˜4k can be connected to each other in a ring shape including between the last connection switching module 4k and the first connection switching module 41, and each base station cell (RRU) is connected to five adjacent baseband signals. It is configured to be connectable to a processing card (BBU).

As in the case of FIG. 1 of the first embodiment, the radio base station apparatus 101 shown in FIG. 8 includes n (n: natural number) base station cells (RRU: Remote Radio Unit remote radio units) 11 to 1n. A baseband processing pool (BBU-pool) 20 that collects and executes each wireless communication processing is provided, and k (k: natural number, k ≦ n) basebands are included in the baseband processing pool (BBU-pool) 20. A signal processing card (BBU: Base Band Unit baseband signal processing module) 21 to 2k is provided. Each of the k (one or plural) baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 20 is connected between n base station cells (RRU) 11 to 1n. While sharing the processing resources, for example, wireless Layer-1 processing (baseband signal processing) such as LTE-Advanced is performed.

As in the case of FIG. 1 of the first embodiment, the RF (Radio Frequency) unit side of each of the k (one or plural) baseband signal processing cards (BBU) 21 to 2k is Via the connection switching control unit 40, each base station cell (RRU) 11 to 1n is connected by an optical fiber, a radio backhaul (fronthaul) or the like. Here, there is no problem even if the radio system to be processed in the baseband processing pool (BBU-pool) 20 is a radio system other than LTE-Advanced, and the layer to be processed is a Layer- other than Layer-1. There is no particular problem even if the second processing is performed.

Also, the radio base station apparatus 101 applies to k baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 20 as in the case of FIG. 1 of the first embodiment. A processing resource allocation control unit 51, a traffic prediction unit 52, a connection information storage unit 53, and the like are also provided for processing resource allocation control.

The connection switching control unit 40 is configured by arranging (connecting) k connection switching modules 41 to 4k in the same manner as the connection switching control unit 30 in the case of FIG. 1 of the first embodiment. Each of the connection switching modules 41 to 4k can perform connection between one or more base station cells (RRU) 11 to 1n and one or more baseband signal processing cards (BBU) 21 to 2k. This configuration is possible and allows interconnection between adjacent connection switching modules.

However, unlike the connection switching control unit 30 in the case of FIG. 1 of the first embodiment, the connection switching control unit 40 can also be interconnected between the last connection switching module 4k and the first connection switching module 41. It is characterized by adopting a simple ring-type connection configuration. For example, of the k connection switching modules 41 to 4k, the i-th (1 ≦ i ≦ k) -th connection switching module 4i is the adjacent (i−1) -th connection switching module 4 (i−1). And the (i + 1) th connection switching module 4 (i + 1) can be connected to each other, but in the case of the first connection switching module 41 with i = 1 or the last connection switching module 4k with i = k. In this case, as the connection switching modules adjacent in a ring shape, the last connection switching module 4k and the first connection switching module 41 can also be connected to each other.

In the first embodiment, each of the k connection switching modules 31 to 3k can be interconnected with one connection switching module adjacent to each other. In the second embodiment, the number of interconnections is expanded to allow interconnection between two connection switching modules adjacent to both sides.

Therefore, in the second embodiment, of the n base station cells (RRU) 11 to 1n, any base station cell (RRU) connected to the i-th connection switching module 4i, for example, the jth The (1 ≦ j ≦ n) th base station cell (RRU) 1j has two BBUs adjacent to each other around the i-th BBU2i corresponding to the connection switching module 4i to which the RRU1j is connected. The (i-2) th BBU2 (i-2), the (i-1) th BBU2 (i-1), the (i + 1) th BBU2 (i + 1) and the (i + 2) th BBU2 The connection can be switched between (i + 2).

Note that, even in the case of the configuration that can be mutually coupled with one connection switching module on each side as shown in the first embodiment, Similarly, it should be noted that the last connection switching module 4k and the first connection switching module 41 can be connected (connected) in a ring shape.

(Description of operation of second embodiment)
Next, an example of the operation of the wireless return station apparatus 101 shown in FIG. 8 as the second embodiment of the present invention will be described in detail with reference to FIG. 9 and FIG. As described above, in each of the k baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 20 of the radio base station apparatus 101 shown in FIG. As in the above embodiment, wireless communication processing, such as Layer-1 processing (baseband signal processing) such as LTE-Advanced, is performed for n base station cells (RRU) 11 to 1n in an integrated manner. .

By sharing processing resources among the k baseband signal processing cards (BBU) 21 to 2k, each base station cell (RRU) for the base station cells (RRU) 11 to 1n can be processed with k baseband signals. Among the processing cards (BBUs) 21 to 2k, in order to change which baseband signal processing card (BBU) is used, each base station cell (RRU) 11 to 1n and each baseband signal processing card (BBU) The connection switching between 21 and 2k is performed by the connection switching control unit 40. Each transmission / reception signal switched by the connection switching control unit 40 is connected to the base station cells (RRU) 11 to 1n that are connected to each other via an optical fiber or a wireless backhaul (fronthaul) and the baseband. Data is transmitted to and received from the signal processing card (BBU) 21-2k.

Here, as a feature of the connection switching control unit 40 in the second embodiment, as described above, two adjacent connection switching modules on both sides can be interconnected. The connection switching modules 41 to 4k are connected to each other up to two adjacent points. Furthermore, the last connection switching module 4k and the first connection switching module 41 are configured to be capable of mutual connection. FIG. 9 is a schematic diagram showing a configuration example of the connection switching modules 41 to 4k according to the second embodiment of the present invention. As a configuration example of each of the connection switching modules 41 to 4k, the i-th (1 ≦ i Taking a connection switching module 4i of ≦ k) as an example, a configuration example is shown in which two adjacent connection switching modules on both sides can be interconnected.

In the example shown in FIG. 9, as in the case of FIG. 2 of the first embodiment, a baseband signal processing module (BBU) that connects one connection switching module 4i to one of BBU # i. Input / output interface, (at least) RRU #j ₁ , RRU #j ₂ , RRU #j ₃ (1 ≦ j ₁ , j ₂ , j ₃ ≦ k) 3 RRU base station cells connected (RRU) I / O interface, two interconnection switching modules 4 (i-2), 4 (i-1), 4 (i + 1), and 4 (i + 2) adjacent to each other. This shows an example in the case of having an input / output interface. That is, no matter how large the traffic is due to only one of the i-th BBU # i connected to the connection switching module 4i, (at least) any three RRUs, for example, j ₁ th RRU # _{j 1,} the _{j 2} th RRU # _{j 2,} to process three RRU of the _{j 3}

th

_{_{RRU # j 3 (1 ≦ j}} 1, j 2, j 3 ≦ k) A configuration example assuming a possible case is shown.

In the case of the configuration example shown in FIG. 9, the first RRU input interface 1 from the _three RRU # j ₁ , RRU # j ₂ , and RRU # j ₃ connected to the connection switching module 4 i is one system, two on each side. 4 of the second RRU input interface 2 from the adjacent connection switching modules 4 (i-2), 4 (i-1), 4 (i + 1) and 4 (i + 2), RRU # j ₁ , RRU # j ₂ , RRU #j ₃ sides two by adjacent connection switching module 4 from (i-2), 4 ( i-1), 4 (i + 1) and 4 (i + 2) the 1RRU output interface 3 is 4 lines towards Then, It comprises a selection circuit (not shown in FIG. 9) that selectively arbitrates each input from each of the first RRU input interface 1 and the second RRU input interface 2.

Although depending on the maximum processing capability of each baseband signal processing card (BBU) 21 to 2k, in the embodiment shown in FIG. 9, a maximum of 15 base station cells (RRU) per BBU, for example, BBU # i. Can be connected and processed. Note that FIG. 9 shows only the signal flow from the RRU side to the BBU side, and does not describe the reverse signal flow from the BBU side to the RRU side. However, it should be noted that in reality, there is almost the same reverse signal flow from the BBU side to the RRU side.

In this way, by connecting a plurality of connection switching modules side by side and interconnecting with two adjacent connection switching modules on both sides, any connection switching module such as connection switching module #i 4i can be connected. base station cell (remote RF unit) for example remote RF unit # _{j 1} is about the BBU example BBU # i the remote RF unit # _{j 1} corresponding to the connected connection switching module for instance connected switching modules #i 4i, a plurality of at least adjacent Between a plurality of BBUs including four BBUs (four in the example of FIG. 9), for example, BBU # (i-2), BBU # (i-1), BBU # i, BBU # (i + 1), BBU # (i + 2) The connection can be switched among the five BBUs.

FIG. 10 shows a connection configuration example of the connection switching modules 41 to 4k according to the second embodiment of the present invention, and a baseband signal processing card for which operation is to be turned off next (that is, operation is to be set to an off state). It is explanatory drawing for demonstrating an example of the mechanism which determines the order of (BBU). In the embodiment of FIG. 10, the number k of connection switching modules 41 to 4k of the connection switching control unit 40 is eight (k = 8) of connection switching module # 1 to connection switching module # 8, and correspondingly. The number k of baseband signal processing cards (BBU) 21 to 2k of the baseband processing pool (BBU-pool) 20 to be connected is also 8 (k = 8) of BBU # 1 to BBU # 8, while the base station The number n of the cells (RRU) 11 to 1n is 24 (n = 24) of RRU # 1 to RRU # 24, and each of the eight connection switching modules 41 to 48 has the connection illustrated in FIG. The case where the switching module is used is shown.

Also, each of the BBU # 1 to BBU # 8 is basically (assuming that traffic is large), and the connection switching module # 1 to connection switching module # 8 corresponding to each of the BBU # 1 to BBU # 8, respectively. The case where the process regarding three RRUs connected to each is performed is shown. That is, BBU # 1 has three RRUs RRU # 1 to RRU # 3, BBU # 2 has three RRUs RRU # 4 to RRU # 6,..., BBU # 7 has RRU # 19 RRU # 21 for RRU # 21 and BBU # 8 perform RRU processing for RRU # 22 to RRU # 24, respectively.

Each of the RRU # 1 to RRU # 24 is a BBU adjacent to each other that is predetermined for each RRU # 1 to RRU # 24 among the BBU # 1 to BBU # 8 of the baseband processing pool (BBU-pool) 20. It is possible to connect only to any of the above. That is, each of RRU # 1 to RRU # 24 is centered on each of BBU # 1 to BBU # 8 connected corresponding to each of connection switching module # 1 to connection switching module # 8 to which each RRU is connected. It is possible to selectively connect to any of a total of five BBUs including at least four BBUs adjacent to both sides. For example, in the case of RRU # 4 in FIG. 10, it is connected to the connection switching module # 2, but two BBU # s on both sides adjacent to each other in a ring shape centering on the correspondingly connected BBU # 2. 8 and BBU # 1, BBU # 3, BBU # 4, and any of the five BBUs (BBU # 8, BBU # 1, BBU # 2, BBU # 3, BBU # 4) can be selected and connected. Is possible.

For example, when the traffic is small, an arbitrary BBU, for example, BBU # 2 out of the eight BBU # 1 to BBU # 8 is centered on the connection switching module # 2 to which the BBU # 2 is connected correspondingly. And five connection switching modules (connection switching module # 8, connection switching module #) including connection switching module # 8, connection switching module # 1, connection switching module # 3, and connection switching module # 4 that are adjacent in a ring shape. 1, a connection switching module # 2, a connection switching module # 3, a connection switching module # 4), and a maximum of 15 RRUs connected thereto can be connected and processed.

That is, for example, in the case of BBU # 2, three of RRU # 4 to RRU # 6 connected to the BBU # 2, and each of the connection switching module # 1 and the connection switching module # 3 adjacent to each other Three RRU # 1 to RRU # 3 and three RRU # 7 to RRU # 9 connected to, and a connection switching module # 8 and a connection switching module # adjacent to the next two in a ring shape 4 and RRU # 22 to RRU # 24 connected to each of the four and three RRU # 10 to RRU # 12 are added up to a total of 15 RRU # 1 to # 12, RRU # 22 to # 24 can be connected for processing.

Next, as illustrated in FIG. 8, the radio base station apparatus 101, like the radio base station apparatus 100 of the first embodiment, performs traffic resource sharing in each BBU in order to share the processing resources ( Processing resource allocation for allocating processing resources of n base station cells (RRU) 11 to 1n to k baseband signal processing cards (BBU) 21 to 2k based on a traffic prediction result by a traffic prediction function) A control unit 51 is provided.

Further, the processing resource allocation control unit 51, based on the traffic predicted by the traffic prediction unit 52, n base station cells (RRU) for each of the k baseband signal processing cards (BBUs) 21 to 2k. 11 to 1n processing resource allocation is controlled. As described in the first embodiment, the purpose of the processing resource allocation control is to operate only as few BBUs as possible and to turn off the operation by sharing processing resources in order to realize low power consumption. The purpose is to increase the number of BBUs that can be performed as much as possible.

Next, an example of processing resource allocation control performed by the processing resource allocation control unit 51 in order to achieve low power consumption in the second embodiment will be further described with reference to the explanatory diagram of FIG. To do. Note that the flow of the overall processing procedure of the processing resource allocation control in the second embodiment is basically the same as that in the first embodiment, and is shown in the control flowchart of FIG. 4 in the first embodiment. The procedure is the same as shown. However, as a specific control operation in the second embodiment, as described above, the configuration of the connection switching modules 41 to 4k is a configuration in which two adjacent connection switching modules on both sides can be interconnected. In addition, since the ring connection between the last connection switching module 4k and the first connection switching module 41 is also possible, it is possible to share processing resources for more RRU processes in any one BBU. Control.

Therefore, for example, in step S1 of the processing resource allocation control flowchart shown in FIG. 4 as the first embodiment, when determining the order of BBUs to be turned off, in the second embodiment, It is possible to set many operation OFF target BBUs.

In the explanatory diagram of FIG. 10, as described above, the mechanism for determining the BBU to be turned off next time in the second embodiment is also shown. In the second embodiment, the RRU connected to the five adjacent connection switching modules at the maximum can be selectively connected to any one BBU. Therefore, in the explanatory diagram of FIG. 10, in addition to the case of the BBU operating state described as “traffic high”, “medium traffic”, and “traffic small” in the case of FIG. 5 showing the operation of the first embodiment. In addition, the BBU operating state case described as “traffic minimum” can also be realized.

Also in the second embodiment, in the process of step S1 in FIG. 4 (the method for determining the BBU to be turned off next), the method for determining the BBU to be turned off is described in the first embodiment. As in the case of the embodiment, the processing resource allocation control unit 51 in FIG. 8 basically wants to turn off the operation at every power-of-two interval according to the traffic amount predicted by the traffic prediction unit 52 ( In other words, the baseband signal processing card (BBU) that is to be set to the off state is selected and set.

That is, for example, as shown in FIG. 10 (A), when the traffic is large, the BBU is to be turned off at an interval of 8 (= 2 ³ ) (that is, the operation is set to the off state). (In the case of the example of FIG. 10, for example, one of BBU # 4 is set out of eight BBUs). Further, as shown in FIG. 10 (B), in the case of moderate traffic, with four (= ^{2 2)} interval, sets the BBU to be in the operation OFF (in the example of FIG. 10, Among the eight BBUs, for example, two of BBU # 4 and BBU # 8 are set). Also, as shown in FIG. 10C, when traffic is small, BBUs to be turned off are set at intervals of 2 (= 2 ¹ ) (in the example of FIG. 10, 8). For example, four BBU # 2, BBU # 4, BBU # 6, and BBU # 8 are set among the BBUs).

Further, as the second case specific to the embodiment of, as shown in FIG. 10 (D), when the traffic of the minima, BBU becomes operational ON is four (= 2 ²⁾ Interval Thus, the BBU to be turned off is set (in the case of the example of FIG. 10, for example, BBU # 2, BBU # 3, BBU # 4, BBU # 6, BBU # 7, and BBU # among the eight BBUs) 6 and 8 are set as BBUs to be turned off.) The reason why such a setting is possible in the second embodiment is that, in the first embodiment, each RRU # 1 to RRU # 24 can connect only up to three adjacent BBUs. Although it was not possible, in the second embodiment, since it is possible to connect up to five adjacent BBUs, all three adjacent BBUs can be turned off. It is.

Further, as the operation state of each baseband signal processing card (BBU) at the time of traffic prediction, the BBU operation state (for example, BBU # 4 or other of 8 BBUs) described in “traffic large” in FIG. If any one of the BBUs is in an operation OFF state, then the BBU operation state described in “traffic” in FIG. 10B (for example, BBU # 4 out of 8 BBUs) , A process resource allocation control is performed aiming at a state where any other two BBUs are turned off at intervals of two or four of BBU # 8. That is, for example, as shown in FIG. 10A, when one BBU of BBU # 4 is in an operation OFF state, as shown in “Low” in FIG. In addition, it aims to turn off the operation of BBU # 8.

If the BBU operating state of “in traffic” of FIG. 10B has already been realized as the operating state of the baseband signal processing card (BBU) at the time of traffic prediction, next, FIG. BBU operating state described in “Small traffic” (e.g., out of 8 BBUs, for example, BBU # 2, BBU # 4, BBU # 6, BBU # 8, or any other 4 BBUs at intervals of 2) The processing resource allocation control is performed aiming at a state where the operation is turned off. That is, for example, as shown in FIG. 10 (B), when two BBUs BBU # 4 and # 8 are in an operation OFF state, as shown in “Low” in FIG. 10 (C), In addition, it aims to turn off the operation of BBU # 2 and BBU # 6 in addition.

If the BBU operating state of “low traffic” in FIG. 10C has already been realized as the operating state of the baseband signal processing card (BBU) at the time of traffic prediction, next, FIG. ) Processing resources aiming at the BBU operating state described in “Traffic minimum” (state in which any other 6 BBUs are turned off so that four BBUs are turned on among the 8 BBUs) Perform allocation control. That is, for example, as shown in FIG. 10C, when four BBUs of BBU # 2, BBU # 4, BBU # 6, and BBU # 8 are in an operation OFF state, as shown in FIG. As shown in “Low”, the BBU # 3 and BBU # 7 are added to the next, and the operation is turned off.

Note that the mechanism of the process of step S2 in FIG. 4 in the second embodiment (a method for determining a baseband signal processing card (BBU) that performs processing resource allocation control) is the same as in the case of the first embodiment. It is the same. The processing resource allocation control unit 51 selects a baseband signal processing card (BBU) that performs processing resource allocation control as far as possible from a BBU that is to be turned off (including BBUs that are already turned off). Processing resource allocation control is performed with priority in order. Here, when there are a plurality of BBUs that are desired to be turned off (that is, the operation is to be set to the off state) and BBUs that are already in the operation OFF state, processing resources are sequentially processed from the BBU located in the middle of the corresponding BBU. Perform allocation control.

For example, the traffic predicting unit 52 predicts that the traffic is large, and for example, BBU # 4 is determined as the BBU to be next turned off among the 8 BBUs, as described in “traffic large” in FIG. If BBU # 4 has already been set to the operation OFF state, as shown in “High1” in FIG. 10A, the BBU that is farthest away from the BBU # 4 Processing resource allocation control is performed preferentially from # 8. Further, as described in “traffic” in FIG. 10B, for example, BBU # 4 and BBU # 8 among the eight BBUs are set as BBUs whose operation is to be turned off next. If determined, or if BBU # 4 and BBU # 8 have already been set to the operation OFF state, as shown in “High1” of FIG. 10B, the BBU # 4 and BBU # The processing resource allocation control is preferentially performed in order from the BBU # 2 or # 6 that is the BBU located farthest from the distance 8, that is, between the BBU # 4 and the BBU # 8.

Note that, as described in “traffic” in FIG. 10B, when there are a plurality of BBUs to be turned off and BBUs that are already turned off, the BBUs that are separated by the same distance from the plurality of BBUs. When there are a plurality of BBUs, the processing resource allocation control may be preferentially performed in order from any BBU among a plurality of BBUs separated by the same degree. In the case of “large traffic” in FIG. 10A, BBU # 1 and BBU # 7 have distances from BBU # 4 as BBUs that preferentially process resource allocation control after BBU # 8. In the case of the same degree, either BBU # 1 or BBU # 7 may be selected as the next priority order of BBU # 8.

(Configuration example of the third embodiment)
Next, a configuration example of a radio base station apparatus according to the third embodiment of the present invention will be described with reference to FIG. FIG. 11 is a block configuration diagram illustrating an example of the overall configuration of the radio base station apparatus according to the third embodiment of the present invention. As the radio base station apparatus, as in the case of FIG. 1 of the first embodiment, An example of the overall configuration of a radio base station apparatus that consolidates radio signal processing and shares its processing resources is shown. However, in the radio base station apparatus 102 shown in FIG. 11 of the third embodiment, unlike the configuration of the connection switching control unit 30 in the case of FIG. 1 of the first embodiment, k basebands The signal processing cards (BBU) 21 to 2k and the n base station cells (RRU) 11 to 1n are clustered in a predetermined unit, and the connection switching control unit 70 is also associated with the clustering. This is shown in the configuration example when processing resources are controlled by partial clustering.

As in the case of FIG. 1 of the first embodiment, the radio base station apparatus 102 shown in FIG. 11 includes n (n: natural number) base station cells (RRU: Remote Radio Unit remote radio units) 11 to 1n. A baseband processing pool (BBU-pool) 90 that collects and executes each wireless communication process is provided, and k (k: natural number, k ≦ n) basebands are included in the baseband processing pool (BBU-pool) 90. A signal processing card (BBU: Base Band Unit baseband signal processing module) 21 to 2k is provided. Each of the k (one or plural) baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 90 is connected between n base station cells (RRU) 11 to 1n. While sharing the processing resources, for example, wireless Layer-1 processing (baseband signal processing) such as LTE-Advanced is performed.

As in the case of FIG. 1 of the first embodiment, the RF (Radio Frequency) unit side of each of the k (one or plural) baseband signal processing cards (BBU) 21 to 2k is The base station cells (RRU) 11 to 1n are connected to each base station cell (RRU) 11n by an optical fiber, a radio backhaul (fronthaul), or the like via the connection switching control unit 70. Here, there is no problem even if the radio system to be processed in the baseband processing pool (BBU-pool) 90 is a radio system other than LTE-Advanced, and the layer to be processed is a Layer- other than Layer-1. There is no particular problem even if the processing is 2 or the like.

However, as a configuration unique to the third embodiment, each baseband signal processing card (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 90 is in a predetermined unit arbitrarily determined. For example, a first signal processing card cluster (first BBU cluster) 91 and a second signal processing card cluster (second BBU cluster) 92 are provided. For example, the baseband signal processing cards (BBU) 21 to 23 are included in the first signal processing card cluster (first BBU cluster) 91, and the baseband signal processing cards (BBU) 24 to 2k are the second signal processing card cluster. (Second BBU cluster) 92.

Similarly, the base station cells (RRU) 11 to 1n are also clustered in units determined in advance. For example, the first base station cell cluster (first RRU cluster) 10A, the second base station cell A cluster (second RRU cluster) 10B and the like. For example, the base station cells (RRU) 11 to 15 are included in the first base station cell cluster (first RRU cluster) 10A, and the base station cells (RRU) 16 to 1n are included in the second base station cell cluster (second RRU cluster). ) Included in 10B.

Further, a part of the connection switching control unit 70 is clustered corresponding to each BBU cluster such as the first signal processing card cluster (first BBU cluster) 91 and the second signal processing card cluster (second BBU cluster) 92. Has been. For example, in FIG. 11, corresponding to the first signal processing card cluster (first BBU cluster) 91, a connection switching module cluster 71 including three connection switching modules # 1 41 to # 3 43 is provided. The remaining connection switching modules in the connection switching control unit 70 are provided corresponding to each baseband signal processing card (BBU) as in the first and second embodiments. For example, in FIG. Are provided with connection switching modules 44 to 4k corresponding to the baseband signal processing cards (BBU) 24 to 2k, respectively. The adjacent connection switching modules are configured to be capable of ring-shaped interconnections as in the second embodiment (or are configured to allow interconnections similar to those in the first embodiment). As good).

Also, the radio base station apparatus 102, as in the case of FIG. 1 of the first embodiment and FIG. 8 of the second embodiment, k basebands in the baseband processing pool (BBU-pool) 90. A processing resource allocation control unit 51, a traffic prediction unit 52, a connection information storage unit 53, and the like are provided for processing resource allocation control for the signal processing cards (BBU) 21 to 2k. Further, as a configuration unique to the third embodiment, in order to enable ON / OFF control of each base station cell (RRU) 11 to 1n in an upper layer, each base station cell (RRU) 11 to A base station cell ON / OFF information storage unit 54 for storing 1n ON / OFF information is also newly provided.

(Description of the operation of the third embodiment)
Next, an example of the operation of radio base station apparatus 102 shown in FIG. 11 as the third embodiment of the present invention will be described in detail. As described above, each of the k baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 90 of the radio base station apparatus 102 shown in FIG. As in the above embodiment, wireless communication processing, such as Layer-1 processing (baseband signal processing) such as LTE-Advanced, is performed for n base station cells (RRU) 11 to 1n in an integrated manner. .

By sharing processing resources among the k baseband signal processing cards (BBU) 21 to 2k, each base station cell (RRU) for the base station cells (RRU) 11 to 1n can be processed with k baseband signals. Among the processing cards (BBUs) 21 to 2k, in order to change which baseband signal processing card (BBU) is used, each base station cell (RRU) 11 to 1n and each baseband signal processing card (BBU) The connection switching between 21 and 2k is performed by the connection switching control unit 70. Each transmission / reception signal switched by the connection switching control unit 70 is connected to the base station cells (RRU) 11 to 1n that are in a connected state via an optical fiber, a radio backhaul (fronthaul), or the like. Data is transmitted to and received from the processing cards (BBU) 21 to 2k.

Here, as a feature of the radio base station apparatus 102 in the third embodiment, as described above, the baseband signal processing cards (BBU) 21 to 2k in the baseband processing pool (BBU-pool) 90 are as follows. Clustering is performed in a predetermined unit that is arbitrarily determined in advance. Similarly, the base station cells (RRU) 11 to 1n are also clustered in units that are determined in advance.

Accordingly, the connection switching control unit 70 is also associated with each signal processing card cluster (BBU cluster) such as the first signal processing card cluster (first BBU cluster) 91 and the second signal processing card cluster (second BBU cluster) 92. For example, the connection switching module cluster 71 may be configured to correspond to the first signal processing card cluster (first BBU cluster) 91, or to correspond to each single baseband signal processing card (BBU) 24 to 2k. Thus, the connection switching modules 44 to 4k may be configured. The connection switching module cluster 71 for each signal processing card cluster (BBU cluster) is limited to simply connecting the single connection switching modules 41 to 43 for each single baseband signal processing card (BBU). For example, all connection combinations between BBUs and RRUs for baseband signal processing cards (BBU) 21 to 23 in the first signal processing card cluster (first BBU cluster) 91 may be used. It is good also as a structure which makes it realizable.

Also in the third embodiment, each connection switching module in the connection switching module cluster 71 of the connection switching control unit 70 and each of the individual connection switching modules 44 to 4k are the same as those in the second embodiment shown in FIG. Alternatively, similar to the configuration shown in FIG. 2 of the first embodiment, at least two adjacent sides (or two) by the interconnection input / output interface (second RRU input interface 2 and first RRU output interface 3) (or The connection switching modules (one on each side) are connected to each other. Therefore, in any base station cell (RRU) among the base station cells (RRU) 11 to 1n, a baseband signal processing card (BBU) corresponding to the connection switching module to which the base station cell (RRU) is connected. It is possible to connect to a total of five (or three) or more baseband signal processing cards (BBU) including at least four (or two) or more adjacent signal processing cards.

Next, as illustrated in FIG. 11, the radio base station apparatus 102, like the radio base station apparatus 100 according to the first embodiment, performs traffic resource sharing in each BBU in order to share the processing resources. Processing resource allocation for allocating processing resources of n base station cells (RRU) 11 to 1n to k baseband signal processing cards (BBU) 21 to 2k based on a traffic prediction result by a traffic prediction function) A control unit 51 is provided.

Next, an example of processing resource allocation control performed by the processing resource allocation control unit 51 in order to realize low power consumption in the third embodiment will be further described. Also in the third embodiment, the overall processing procedure flow of the processing resource allocation control is basically the same as that of the first embodiment, and the control of FIG. 4 of the first embodiment is performed. The procedure is the same as that shown in the flowchart. However, as a specific control operation in the third embodiment, as described above, it is assumed that the ON / OFF control of each base station cell (RRU) 11 to 1n is performed in the upper layer, and from the upper layer, The notified base station cell (RRU) ON / OFF information is stored in the base station cell ON / OFF information storage unit 54 so as to be referred to when processing resource allocation is controlled.

That is, the processing resource allocation control unit 51 receives notification from the upper layer in addition to the traffic result notified from the traffic prediction unit 52 and the RRU-BBU connection information stored in the connection information storage unit 53. Then, processing resource allocation control is performed using base station cell (RRU) ON / OFF information stored in the base station cell ON / OFF information storage unit 54.

Note that when the traffic prediction unit 52 performs traffic prediction, the traffic prediction is also performed with reference to the base station cell (RRU) ON / OFF information stored in the base station cell ON / OFF information storage unit 54. . The traffic prediction result predicted by the traffic prediction unit 52 is notified to the processing resource allocation control unit 51, and is reflected in the process of step S1 of the control flowchart of FIG. 4 for performing the processing resource allocation control.

The processing resource allocation control unit 51 uses, for example, the operating base station cell (RRU) 11 as a reference result of the base station cell (RRU) ON / OFF information stored in the base station cell ON / OFF information storage unit 54. When it is detected that any one of ˜1n is OFF, the RRU processing resource allocation is performed from the baseband signal processing card (BBU) to which the RRU processing resource related to the base station cell (RRU) has been allocated. After deleting in advance, the processing resource allocation control shown in the control flowchart of FIG. 4 of the first embodiment is performed. As a result, the determination result of the baseband signal processing card (BBU) order of the operation OFF target based on the traffic prediction result shown in step S1 of FIG. 4 and each target baseband signal processing shown in steps S3 and S4 of FIG. The calculation result of the processing resource usage rate of the card (BBU) will be affected.

On the other hand, as a reference result of the base station cell (RRU) ON / OFF information stored in the base station cell ON / OFF information storage unit 54 by the processing resource allocation control unit 51, for example, a base station that is in an operation OFF state When it is detected that one of the cells (RRU) 11 to 1n is in the operation ON state, the base station signal processing in which the base station cell (RRU) is connectable and is in the operation ON state When the card (BBU) is present, the baseband signal processing card (BBU) in which the connection distance of the base station cell (RRU) is the nearest among the baseband signal processing cards (BBU) in the operation ON state. ) Once, after temporarily assigning temporary processing resources for the base station cell (RRU), the control flowchart of FIG. 4 of the first embodiment. The processing resource allocation control shown performed.

Note that, by assigning a temporary processing resource related to the base station cell (RRU), the processing resource usage rate of the baseband signal processing card (BBU) exceeds a predetermined upper limit threshold A. Even if the base station cell (RRU) is connectable and there is no base-band signal processing card (BBU) that is in operation ON state, After allocating temporary processing resources to the baseband signal processing card (BBU) to which the base station cell (RRU) is connectable and the connection distance of the base station cell (RRU) is closest, The processing resource allocation control shown in FIG. 4 is performed. The reason is that a baseband signal that is not connected to the base station cell (RRU) by temporarily allocating processing resources to the baseband signal processing card (BBU) having the shortest connection distance of the base station cell (RRU). This is because it is possible to prevent a case where processing resources need to be allocated to the processing card (BBU).

(Description of effects of the first, second, and third embodiments)
As described in detail above, the following effects can be expected in each embodiment of the present invention.

The first effect is to reduce the circuit scale of the connection switching

control units

30, 40, and 70 in the radio base station apparatuses 100 to 102 that consolidate radio communication processes for a plurality of base station cells (RRU) 11 to 1n. Thus, it is possible to realize downsizing of the apparatus and low power consumption.

The reason is that, in the radio base station apparatuses 100 to 102 according to the respective embodiments of the present invention, the connection switching

control units

30, 40 and 70 are connected between the base station cell (RRU) and the baseband signal processing card (BBU). Since a plurality of connection switching modules 31 to 3k and 41 to 4k with limited connections are arranged side by side, or partially clustered as in the connection switching module cluster 71 of the third embodiment. Compared with the conventional connection switching unit that realizes all ideal connection combinations between the base station cell (RRU) and the baseband signal processing card (BBU), the circuit scale can be greatly reduced. is there.

That is, when realizing all ideal connection combinations, the circuit scale is proportional to the multiplication of the respective numbers, such as “the number of RRUs × the number of BBUs”, whereas in each embodiment of the present invention In the case of the connection switching

control units

30, 40, and 70, it is possible to suppress the circuit scale to be linearly proportional only to the number of BBUs, such as “(limited RRU number) × BBU number”. Here, the “limited number of RRUs” is 9 in the case of the first embodiment, 15 in the example of the second embodiment, etc., and is a constant value arbitrarily set in advance. is there.

As for the effects of reducing the device scale and reducing the power consumption by reducing the circuit scale like this, traffic will increase in the future and more base station cells (RRU) and baseband signal processing cards (BBU) will be consolidated. Needless to say, this is particularly remarkable as compared with a conventional connection switching control unit that exponentially increases the circuit scale in an attempt to realize all ideal connection combinations.

The connection switching modules 31 to 3k and 41 to 4k are basically provided for each baseband signal processing card (BBU) as in the first and second embodiments. Even if it is configured corresponding to each unit of the signal processing card cluster (BBU cluster) as in the connection switching module cluster 71 of the third embodiment, the above-described effects are not affected at all. In other words, although it is based on a device architecture that can be expanded with a uniform configuration of all connection switching modules, depending on the case, each of those shown in the first, second, and third embodiments. There is no problem even if the device architecture is such that the configurations of the connection switching modules 31 to 3k, 41 to 4k and the connection switching module cluster 71 are mixed.

The second effect is that the radio base station apparatuses 100 to 102 that aggregate radio communication processes for a plurality of base station cells (RRU) 11 to 1n intend to expand the apparatus in order to cope with traffic increase and the like. In addition, the base station cell (RRU) 11 to 1n of the base station cell radio unit 10 and the baseband signal processing card (BBU) 21 to 2k of the baseband processing pool (BBU-pool) 20 and 90, as well as connection switching Including the connection switching modules 31 to 3k and 41 to 4k of the

control units

30, 40, and 70, it can be linearly expanded as much as necessary, and the expandability is improved.

The reason is that, in the radio base station apparatuses 100 to 102 according to the embodiment of the present invention, the connection switching

control units

30, 40, and 70 are connected between a base station cell (RRU) and a baseband signal processing card (BBU). As in the first and second embodiments, a plurality of connection switching modules 31 to 3k and 41 to 4k having an interconnection interface with an adjacent connection switching module are connected side by side, The connection switching modules 31 to 3k and 41 to 4k are also connected to the base station cells (RRU) 11 to 11 in the same manner as in the connection switching module cluster 71 of the embodiment. Similar to 1n and baseband signal processing cards (BBU) 21 to 2k, for example, it may be expanded linearly according to the “number of BBUs” to be expanded. It is.

Next, regarding the second effect, problems in the prior art will be described with reference to the explanatory diagram of FIG. FIG. 12 shows problems in the case of using an ideal connection switching unit such as a crossbar type that realizes all connection combinations between a base station cell (RRU) and a baseband signal processing card (BBU). It is explanatory drawing for demonstrating. Here, in the case of a connection switching unit having an ideal configuration, all connections of “the number of RRUs × the number of BBUs” are required. Therefore, even if one RRU or one BBU is expanded, the number of existing RRUs And expansion depending on the number of BBUs is required.

For example, as shown in FIG. 12A, the number M of base station cells (RRU) is four (RRU # 1 to RRU # 4), and the number N of baseband signal processing cards (BBUs) is BBU # 1 to RBU # 1. When using the ideal crossbar (interconnection network) type connection switching unit A that realizes all connection combinations between three BBU # 3, add one RRU # 5 and one BBU # 4 If an attempt is made, as shown in FIG. 12B, in order to realize all connection combinations of “M (= 5) × N (= 4)”, the connection switching unit A is changed to the connection switching unit. Therefore, there is a problem that expandability is lowered because the entire connection switching unit needs to be changed.

Alternatively, as shown in FIG. 12C, all connection combinations are abandoned, and connection switching that realizes all connection combinations between the existing base station cell (RRU) and the baseband signal processing card (BBU) is performed. It is also possible to add a dedicated connection switching unit C for connecting only the added RRU # 5 to BBU # 4 while leaving the part A as it is. However, in the case of FIG. 12C, there is a problem that processing resources cannot be shared between the BBU # 4 to be added and the existing BBUs # 1 to # 3.

On the other hand, in each embodiment of the present invention, the connection switching module shown in FIG. 2 or FIG. 9 is necessary depending on the addition of base station cells (RRU) or baseband signal processing cards (BBU). There is an advantage that the number of connection switching modules can be increased in such a way that processing resources can be shared with existing facilities only by adding connection switching modules to the connection switching

control units

30, 40, and 70.

The third effect is that the connection switching

control units

30, 40, and 70 having connection restrictions are used in the radio base station apparatuses 100 to 102 that aggregate radio communication processing for a plurality of base station cells (RRU) 11 to 1n. Even in this case, it is possible to realize processing resource sharing substantially equivalent to the case where an ideal connection switching unit is used, and to obtain substantially the same low power consumption effect.

This is because, in the base station cell processing resource allocation method in each embodiment of the present invention, a baseband signal processing card (BBU) to be turned off (that is, to set the operation to the off state) is determined in advance. This is because the processing resource allocation control is preferentially performed in order from the baseband signal processing card (BBU) that is distant from the baseband signal processing card (BBU) to be turned off. Furthermore, when the processing resource usage rate of the allocation target baseband signal processing card (BBU) exceeds a predetermined upper limit threshold A, a base that is distant from the allocation target baseband signal processing card (BBU). The allocation transfer control is performed with priority in order from the band signal processing card (BBU), and when the processing resource usage rate falls below a predetermined lower limit threshold B, the allocation target baseband signal processing card (BBU) This is because processing resource allocation control is performed such that allocation transfer control is preferentially performed in order from the baseband signal processing card (BBU) located in the vicinity of ().

Thus, almost the same processing resource sharing is possible as when using an ideal connection switching control unit that enables connection between a base station cell (RRU) and a baseband signal processing card (BBU) in all connection combinations. Low power consumption can be realized.

Specifically, the base station cell processing resource allocation method is a method in which processing is allocated in order from a base station cell (RRU) having a connection distance as close as possible to an arbitrary baseband signal processing card (BBU). This is because it employs a method that can prevent an attempt to assign a process of an arbitrary base station cell (RRU) to a baseband signal processing card (BBU) having no connection relationship. is there.

Another reason is that a baseband signal processing card (BBU) that is distant from the baseband signal processing card (BBU) while being conscious of the baseband signal processing card (BBU) to be turned off in advance. By allocating RRU processing resources in order, it is possible to allocate as many RRU processes as possible to the remaining baseband signal processing cards (BBUs) that are scheduled to be in the operation ON state. This is because the probability that the signal processing card (BBU) can actually be set to the operation OFF state can be increased.

FIG. 13 is a schematic diagram for explaining the processing resource sharing effect between the base station cell processing resource allocation method according to the embodiment of the present invention and the conventional base station cell processing resource allocation method. The processing resource sharing effect in the case of using a connection switching unit limited to one connection on each side is shown. FIG. 13A shows a case where the conventional base station cell processing resource allocation method described in Non-Patent Document 1 is applied, and FIG. 13B shows the case of the first embodiment of the present invention. The case where the base station cell processing resource allocation method is applied is shown. In addition, in the example shown in FIG. 13, as shown in the figure, it is assumed that the power consumption of the baseband signal processing card (BBU) is broken down. ) Is 30%, and the power consumption (load dependent portion) proportional to the operation rate (processing resource usage rate) is 70%. Also, it is assumed that the traffic of RRU processing in each of BBU # 1 to BBU # 4 has changed from 90%, 100%, 100%, 30% to 90%, 30%, 100%, 30% To do.

In the case of the conventional processing allocation method as described in Non-Patent Document 1, since the baseband signal processing card (BBU) processing order and the base station cell (RRU) processing order are not particularly conscious, FIG. As shown in FIG. 5B, although the RRU process corresponding to 10% of the 30% operation rate of BBU # 2 can be moved to BBU # 1, the remaining 20% operation rate of BBU # 2 and BBU # 4 Even when trying to share resources for RRU processing with a utilization rate of 30%, base station cells (RRUs) corresponding to each RRU processing are located in remote locations that are not included in one adjacent side. It is impossible to connect to the card (BBU), and it is not possible to move the processing related to the base station cell (RRU).

Therefore, processing resource sharing cannot be sufficiently performed, and all four baseband signal processing cards (BBUs) are in an operating state. As a result, as shown in FIG. 13A, the power consumption is 74% as a result of all baseband signal processing cards (BBU) being in the ON state.

On the other hand, in the processing resource allocation method in the embodiment of the present invention, since the baseband signal processing card (BBU) processing order and the base station cell (RRU) processing order are conscious, as shown in FIG. In addition, the RRU process corresponding to 33% of the 100% operation rate of BBU # 3 is moved to BBU # 2, and all the processing corresponding to the 30% operation rate of BBU # 2 of BBU # 4 is further transferred to BBU # 2. 3 and BBU # 4 can be set to an operation OFF state.

Therefore, as shown in FIG. 13B, among all the baseband signal processing cards (BBU), the operation ON state is BBU # 1 to BBU # 3, resulting in a power consumption of 66%. A low power consumption effect equivalent to that obtained when an ideal connection switching unit is used can be obtained.

The configuration of the preferred embodiment of the present invention has been described above. However, it should be noted that such embodiments are merely examples of the present invention and do not limit the present invention in any way. Those skilled in the art will readily understand that various modifications and changes can be made according to a specific application without departing from the gist of the present invention.

In the above-described embodiment, the present invention has been described as a hardware configuration, but the present invention is not limited to this. The present invention can also realize arbitrary processing by causing a CPU (Central Processing Unit) to execute a computer program. Further, the above-described program can be stored using various types of non-transitory computer readable media and supplied to a computer. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (eg, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg, magneto-optical disks), CD-ROM (Read Only Memory) CD-R, CD -R / W, including semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)). In addition, the program may be supplied to the computer by various types of temporary computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

This application claims priority based on Japanese Patent Application No. 2014-174067 filed on August 28, 2014, the entire disclosure of which is incorporated herein.

DESCRIPTION OF SYMBOLS 1 1st RRU input interface 2 2nd RRU input interface 3 1st RRU output interface 10 Base station cell radio | wireless part (RRU)
10A First base station cell cluster (first RRU cluster)
10B Second base station cell cluster (second RRU cluster)
11 to 1n Base station cell (RRU)
20 Baseband processing pool (BBU-pool)
21-2k Baseband signal processing card (BBU)
30 Connection switching control unit 31 to 3k Connection switching module 40 Connection switching control unit 41 to 4k Connection switching module 51 Processing resource allocation control unit 52 Traffic prediction unit (traffic prediction function)
53 Connection Information Storage Unit 54 Base Station Cell (RRU) ON / OFF Information Storage Unit 70 Connection Switching Control Unit 71 Connection Switching Module Cluster 81 Upper Layer Processing Unit 90 Baseband Processing Pool (BBU-pool)
91 First signal processing card cluster (first BBU cluster)
92 Second signal processing card cluster (second BBU cluster)
100 radio base station apparatus 101 radio base station apparatus 102 radio base station apparatuses A1 to A8 processing resource allocation control processing steps B1 to B5 processing resource allocation control processing steps S1 to S6 processing resource allocation control processing steps

Claims

In a radio base station apparatus that aggregates radio communication processing for a plurality of base station cells, a baseband processing pool that aggregates and accommodates one or more baseband signal processing modules, and each of the baseband signal processing modules A processing resource allocation control unit that performs processing resource allocation for each of the base station cells, and a connection switching control unit that performs connection switching between the baseband signal processing module and the base station cell, and the connection The switching control unit includes one or a plurality of connection switching modules, and each of the connection switching modules is limited to any one of the one or more baseband signal processing modules adjacent to each other predetermined for each base station cell. To connect to the baseband signal processing module. A baseband signal processing module input / output interface and a base station cell input / output interface connected to the base station cell and interconnecting one or more adjacent connection switching modules A radio base station apparatus comprising an input / output interface and connected to each other.
The processing resource allocation control unit turns off the operation of each of the baseband signal processing modules prior to the operation of performing the processing resource allocation control of each base station cell for each of the baseband signal processing modules. The radio base station apparatus according to claim 1, wherein a candidate of a baseband signal processing module to be set is set in advance.
When the processing resource allocation control unit allocates the processing resource of each base station cell to each of the baseband signal processing modules, the processing resource allocation control unit starts from the candidate of the baseband signal processing module to set the operation to the off state. 3. The radio base station apparatus according to claim 2, wherein processing resource allocation control is performed with priority given in order from a baseband signal processing module located at a distant position.
When the processing resource usage rate of the baseband signal processing module in the operating state exceeds a predetermined upper limit value, the processing resource allocation control unit is located at a base at a position where the connection distance from the baseband signal processing module is far away. 4. The radio according to claim 1, wherein processing resource switching control for moving from the baseband signal processing module to another baseband signal processing module with priority in order from processing related to a station cell is performed. Base station device.
When the processing resource usage rate of the baseband signal processing module in the operating state is lower than a predetermined lower limit value, the processing resource allocation control unit is located at a position where the connection distance from the baseband signal processing module is short 5. The radio base station apparatus according to claim 1, wherein processing resource switching control to be assigned to the baseband signal processing module is performed with priority in order from processing related to a cell.
As the input / output interface for interconnection provided in each connection switching module, one input / output interface interconnected with each one of the connection switching modules adjacent to each of the connection switching modules, or 6. The wireless communication device according to claim 1, further comprising any one of two input / output interfaces interconnecting each of the connection switching modules and two adjacent connection switching modules. Base station device.
The radio base station apparatus according to any one of claims 1 to 6, wherein each of the connection switching modules is configured to be connected in a ring shape by the interconnection input / output interface.
The processing resource allocation control unit is configured to provide on / off control information of the base station cell notified from an upper layer prior to an operation of allocating processing resources of the base station cell to the baseband signal processing modules. When a base station cell whose operation has changed from an off state to an on state is detected, a baseband signal that is close to the connection distance from the base station cell and is in an on state. The radio base station apparatus according to any one of claims 1 to 7, wherein temporary processing resource allocation control related to the base station cell is performed with priority in order from the processing module.
In a radio base station apparatus that aggregates radio communication processing for a plurality of base station cells, each base station cell may be connected to each baseband signal processing module that is aggregated and accommodated in a baseband processing pool. Possible baseband signal processing modules are limited to any one or more adjacent baseband signal processing modules predetermined for each base station cell, and for each baseband signal processing module Prior to the operation of performing processing resource allocation control of each base station cell, a baseband signal processing module candidate to be set to be turned off among the baseband signal processing modules is set in advance. A base station cell processing resource allocation method.
A non-transitory computer-readable storage medium storing a base station cell processing resource allocation program, wherein the base station cell processing resource allocation method according to claim 9 is implemented as a program that can be executed by a computer. Medium.