KR101737617B1 - Method for transmitting downlink traffic of radio remote unit and radio remote unit apparatus - Google Patents

Abstract

The present invention relates to a method to transmit downlink traffic of a base station and a base station apparatus. More specifically, according to the present invention, the method to transmit downlink traffic of a base station comprises: (a) a step of allocating a resource block (RB) to each of a plurality of traffics stored in a buffer; (b) a step of determining if the number of RBs allocated to a traffic exceeds a preset threshold or not; (c) a step of determining if there exists a pre-designated type of traffic from the traffics to which the RBs are allocated; and (d) a step of waiting for the next transmission time interval (TTI). The step (c) is conducted when it is determined in the step (b) that the number of RBs allocated to traffic does not exceed the preset threshold. The step (d) is conducted when it is determined in the step (c) that there does not exist a pre-designated type of traffic from the traffic to which the RBs are allocated. The present invention is to provide a method to transmit downlink traffic of a base station and a base station apparatus, which are capable of reducing power consumption of the base station, even when the load of the base station is high.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of transmitting downlink traffic of a base station,

The present invention relates to a downlink traffic transmission method and a base station apparatus of a base station, and more particularly, to a method and apparatus for allocating an RB to each traffic until a number of resource blocks (RBs) allocated to each traffic exceeds a predetermined threshold value, To a downlink traffic transmission method and a base station apparatus of a base station that reduce the power amplifier power of a base station by transmitting all the RB-allocated traffic all at once when the total number of allocated RBs exceeds a threshold value.

With the continuous increase of mobile communication traffic, new frequency acquisition and base station expansion are being done. Such a base station extension should be made to a level that can accommodate the maximum traffic generated in the area. When the base station is thus installed, unnecessary power consumption occurs at a time when user traffic is low.

In fact, in order to reduce unnecessary power consumption, the traffic usage pattern of a mobile communication user varies greatly with time. In order to reduce unnecessary power consumption, a base station power such as turning off some base stations or turning off some antennas of a base station Saving technology was used.

However, the on / off operation of the base station and the antenna on / off technology takes time from several tens of seconds to several minutes. As a result, it is obvious that there is almost no user at a predetermined time such as a subway station There is a limit that can be applied only to the region. Also, there is a problem that it is difficult to solve the power saving corresponding to the traffic pattern of the base station base station in seconds or ms, which occurs as the users of the base station intermittently use the communication service such as the web access, the call, and the video streaming in the daytime.

In order to solve this problem, as shown in FIG. 1, a technology for turning on / off a power amplifier (PA) of a base station in units of LTE OFDM symbols has emerged as a technology for reducing power consumption of a base station. The base station PA on / off technology can turn on / off the base station's PA in a time unit shorter than the transmission time interval (TTI) of the base station. Thus, unlike the existing base station on / off and base station antenna on / There are applicable advantages.

However, since the PA is turned off only at the moment when there is no traffic according to the traffic pattern of the user, the rate of PA turn-off is reduced when the load of the base station is slightly increased.

A problem to be solved by an embodiment of the present invention is to provide a technique capable of reducing power consumption of a base station even when a base station load is high by collecting traffic of a plurality of users as much as possible and transmitting the same at a time.

Also, it is aimed to provide a technology that can increase the power saving efficiency of the base station without affecting the quality of the service that the user perceives by allowing the exceptionally instantaneous transmission of the service traffic such as the delay-time-sensitive VoLTE (Voice over LTE).

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

The downlink traffic transmission method of a base station according to an embodiment of the present invention includes the steps of: (a) allocating an RB (Resource Block) to each of a plurality of traffic stored in a buffer according to a scheduling technique; (b) Determining whether a total number of RBs exceeds a predetermined threshold; (c) determining whether there is traffic of a designated type of traffic among the RB allocated traffic; (d) Wherein the step (c) is performed when it is determined that the number of RBs allocated to traffic in the step (b) does not exceed a predetermined threshold, and the step (c) d) is performed when it is determined in step (c) that the traffic of the predetermined type among the traffic allocated to the RB does not exist.

(E) transmitting the traffic allocated by the RB and removing the transmitted traffic from the buffer before step (d), wherein the step (e) When it is determined that the number of the allocated RBs exceeds the predetermined threshold value or when it is determined in the step (c) that the RB is determined to have the traffic of the predetermined type among the allocated traffic.

In addition, the scheduling in the step (a) may proceed according to the priority information of the plurality of traffic.

In addition, the predetermined type of traffic may be traffic whose allowable waiting time is shorter than the predetermined time.

The base station apparatus according to an embodiment of the present invention includes a buffer for storing traffic received from an external device and an RB (Resource Block) for each of the plurality of traffic stored in the buffer according to a given scheduling scheme And a controller configured to determine whether the number of RBs allocated to the traffic exceeds a predetermined threshold, wherein the controller determines that the number of RBs allocated to the traffic does not exceed a predetermined threshold value , It is determined whether there is a predetermined type of traffic among the traffic allocated to the RB, and if there is no traffic of the designated type, control is performed such that the next TTI (Transmission Time Interval) is not transmitted without transmitting the RB .

In this case, if the controller determines that the number of RBs allocated to the traffic exceeds the predetermined threshold, or determines that the traffic of the designated type is present among the traffic allocated to the RB, And remove the transmitted traffic from the buffer.

In addition, the scheduler may schedule according to priority information of the plurality of traffic.

In addition, the predetermined type of traffic may be traffic whose allowable waiting time is shorter than a predetermined time.

According to an embodiment of the present invention, a program stored in a computer readable recording medium for performing a downlink traffic transmission method of a base station comprises the steps of: (a) allocating an RB (Resource Block) to each of a plurality of traffic stored in a buffer according to a scheduling technique (B) determining whether the number of RBs assigned to the traffic exceeds a predetermined threshold; and (c) determining whether there is a predetermined type of traffic among the allocated RBs And (d) waiting for a next TTI (Transmission Time Interval), wherein the step (c) comprises: determining that the number of RBs allocated to traffic in the step (b) does not exceed a predetermined threshold value (D) is performed when it is determined that the traffic of the predetermined type is not present among the traffic allocated to the RB in the step (c) It is.

A computer-readable recording medium having recorded thereon a program according to an embodiment of the present invention includes a program code for causing a processor to perform the steps of: (a) assigning, to each of a plurality of traffic stored in a buffer according to a scheduling technique, (B) determining whether the number of RBs assigned to the traffic exceeds a predetermined threshold value, and (c) determining whether or not there is a traffic of a designated type among the traffic allocated to the RB And (d) waiting for a next TTI (Transmission Time Interval), wherein the operation (c) includes: when the number of RBs allocated to traffic in the operation (b) exceeds a predetermined threshold value , And (d) operation is performed when it is determined that the traffic of the predetermined type among the traffic allocated to the RB in the operation (c) does not exist To be executed.

According to the embodiment of the present invention, it is possible to reduce the power by increasing the rate at which the power amplifier (PA) can be turned off even when the load on the base station increases as in the case of a weekday with a lot of traffic.

At the same time, the power saving efficiency of the base station can be increased without affecting services such as delay-time-sensitive Voice over LTE (VoLTE).

The effects of the embodiments of the present invention are not limited to the above-mentioned effects, and various effects can be included within the scope that is obvious to a person skilled in the art from the following description.

FIG. 1 is a diagram for explaining a technique for turning on / off a power amplifier (PA) of a base station in order to reduce power consumption of a conventional base station.
FIG. 2 is a graph illustrating the number of times of using RBs (Resource Blocks) for collecting and transmitting traffic according to an exemplary embodiment of the present invention.
3 is a functional block diagram of a base station apparatus according to an exemplary embodiment of the present invention.
4 is a diagram for explaining a downlink traffic transmission method of a base station according to an embodiment.
FIG. 5 is a diagram illustrating experimental results of power consumption and PA off ratio when a conventional PA on / off technique and the present invention are applied to a base station.

DETAILED DESCRIPTION OF THE EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

The embodiments disclosed herein should not be construed or interpreted as limiting the scope of the present invention. It will be apparent to those of ordinary skill in the art that the description including the embodiments of the present specification has various applications. Accordingly, any embodiment described in the Detailed Description of the Invention is illustrative for a better understanding of the invention and is not intended to limit the scope of the invention to embodiments.

The functional blocks shown in the drawings and described below are merely examples of possible implementations. In other implementations, other functional blocks may be used without departing from the spirit and scope of the following detailed description. Also, although one or more functional blocks of the present invention are represented as discrete blocks, one or more of the functional blocks of the present invention may be a combination of various hardware and software configurations that perform the same function.

In addition, the expression "including any element" is merely an expression of an open-ended expression, and is not to be construed as excluding the additional elements.

Further, when a component is referred to as being connected or connected to another component, it may be directly connected or connected to the other component, but it should be understood that there may be other components in between.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram for explaining a technique for turning on / off a PA (Power Amplifier) of a base station in order to reduce power consumption of a conventional base station. FIG. 2 is a diagram illustrating a method of collecting and transmitting traffic according to an embodiment of the present invention. And a RB (Resource Block) usage.

Referring to FIG. 1, a method of transmitting traffic in an existing base station apparatus is a method of allocating an RB (Resource Block) to traffic for each TTI (Transmission Time Interval) and transmitting the traffic.

Therefore, when using the technology to turn on / off the power amplifier (PA) of the base station in units of LTE OFDM symbols to reduce the power consumption of the base station, the power amplifier (PA) However, it is difficult to reduce power consumption by reducing the time required for the PA to be turned off during the daytime when the base station transmits a large amount of traffic.

2, in the embodiment of the present invention, traffic is not transmitted every TTI when traffic is transmitted, but when the sum of the number of RBs allocated to traffic exceeds a predetermined threshold value It is possible to increase the power saving effect of the base station by increasing the time that the base station PA can be turned off by transmitting the traffic at one time.

3 and 4, the steps as a configuration and a method as an apparatus according to an embodiment of the present invention will be described in detail.

3 is a functional block diagram of a base station apparatus 300 according to an embodiment of the present invention.

3, the base station apparatus 300 includes a buffer 310, a scheduling unit 320, and a control unit 330. As shown in FIG.

The buffer 310 stores the traffic received from the external device.

Here, the external device includes a user terminal or a server through which the user terminal sends traffic. At this time, the base station apparatus 300 may further include a communication module (not shown) for exchanging data with an external apparatus.

The scheduler 320 determines a priority to allocate RBs to a plurality of traffic stored in the buffer 310 and allocates RBs to each of the plurality of traffic.

For example, traffic having a high priority, for example, a QoS class identifier (QCI), among a plurality of traffic existing in the buffer 310 within a specific TTI can be preferentially transmitted, and all traffic having a high QCI After the RB allocation is completed, the RB allocation for traffic having a low QCI can be performed. Or the RB allocation may proceed in the order that the traffic arrives at the base station.

At this time, the allocation can be completed when the number of RBs allocated to the traffic exceeds the number of RBs usable in the corresponding TTI, or when RBs are allocated to all the traffic existing in the base station buffer.

The control unit 330 determines whether the total number of RBs allocated to the traffic exceeds a preset threshold value after the scheduling unit 320 completes allocation of the RBs. Accordingly, the control unit 330 can control whether the RB transmits the allocated traffic or waits until the next TTI. The detailed control process of the controller 330 according to the above conditions will be described later in detail with reference to FIG.

Meanwhile, when the controller 330 transmits the traffic to which the RB is allocated, the control unit 330 can remove the traffic transmitted from the buffer 310, from the buffer 310.

The scheduling unit 320, the control unit 330 included in the embodiment of the base station apparatus 300 described above includes a memory including instructions programmed to perform these functions, and a microprocessor for executing these instructions. Lt; / RTI >

4 is a diagram for explaining a downlink traffic transmission method of a base station according to an embodiment of the present invention. The downlink traffic transmission method of the base station according to FIG. 4 can be performed by the base station apparatus 300 described with reference to FIG. 3, and each step will be described below.

First, the scheduler 320 allocates or schedules an RB (Resource Block) to each of a plurality of traffic stored in the buffer 310 (S410). In this case, priority can be assigned to each RB to be allocated first by type of traffic.

The step S410 of scheduling a plurality of traffic according to an exemplary embodiment may schedule traffic having a high QCI (Quality Class Identifier) among a plurality of traffic existing in a buffer in a specific TTI to be preferentially transmitted, The scheduling for traffic having a low QCI can be performed after the scheduling for all the traffic having the low QCI is completed.

In this case, prioritization is also required between the traffic having the same QCI. In order to ensure efficient use of RB and fairness between users, it is possible to consider both the channel state of the user and the existing cumulative transmission rate for each user. For this, priority of each traffic can be determined using Equation (1) below.

는 기지국 장치가 단말로부터 미리 수신한 CQI(Channel Quality Information), PMI(Precoding Matrix Index), RI(Rank Index) 등의 무선 채널 상태 정보를 고려한, i 번째 단말이 k 번째 RB를 할당 받을 경우 예상되는 전송 속도이다.

의 경우 i 번째 단말이 기존에 해당 기지국으로부터 서비스 받은 전송 속도의 이동 평균 값으로 아래 [수학식 2]와 같은 식으로 매 TTI 마다 업데이트 될 수 있다. 이에 따라 동일한 QCI 를 가지는 트래픽간

값이 큰 순서로 우선순위를 정할 수 있다. here

Is estimated when the i < th > terminal is allocated to the k < th > RB considering the radio channel state information such as CQI (Channel Quality Information), PMI (Precision Matrix Index) and RI (Rank Index) Transmission speed.

The moving average value of the transmission rate that the i < th > terminal has previously received from the corresponding base station can be updated every TTI in the same manner as in Equation (2) below. Thus, between traffic with the same QCI

You can prioritize in order of increasing value.

는 t 번째 TTI에서 i 번째 단말이 얻은 전송 속도이다. 따라서 [수학식 1]에 따르면 해당 TTI에 무선 채널이 높은 단말에 우선적으로 RB를 할당하되, 만약 특정 단말 무선 채널이 상대적으로 좋지 않아 오랜 기간 동안 RB를 할당 받지 못한 경우는

항에 의해 시간이 지날수록 우선순위가 높아지게 되어 사용자 간의 공평성이 보장된다.Here, β is a constant that can be changed according to the setting,

Is the transmission rate obtained by the i-th UE in the t-th TTI. Therefore, according to Equation (1), RBs are preferentially allocated to a terminal having a high radio channel in the corresponding TTI. If a specific terminal radio channel is relatively inferior and the RB is not allocated for a long period of time

The higher the priority, the more equitable the users are.

There are various variations to adjust the mutual priority order between the efficient use of RB and the fairness guarantee between users by adding two constants such as ε and φ as in Equation (3) above, but basically, Equation (1) is the same as Equation (1) in that consumption is not considered.

The step S410 of scheduling a plurality of traffic according to another embodiment may perform the scheduling in the order that the traffic arrives at the base station. Therefore, it is possible to schedule the ranking by allocating RBs to the traffic arriving at the base station.

Next, the control unit 330 determines whether the number of RBs allocated to the traffic exceeds a predetermined threshold (S420).

The predetermined threshold value can be set to a value that does not exceed the maximum number of RBs that can be allocated when traffic transmission is performed. The reason for setting the threshold value is that the traffic is not transmitted every TTI and the number of RBs allocated to the traffic exceeds the threshold value. If the number of RBs allocated to the traffic exceeds the threshold value, So that it is possible to increase the time during which the PA of the base station can be turned off.

On the other hand, if the number of RBs allocated to the traffic exceeds a predetermined threshold (Yes in S420) as a result of determining whether the threshold has been exceeded (S420), the RB transmits the traffic allocated to the RB in the corresponding TTI, (S440).

Alternatively, if it is determined that the number of RBs allocated to the traffic does not exceed the predetermined threshold value (No in S420) as a result of determining whether the threshold value is exceeded (S420), it is determined whether the RB- I need confirmation. Delay-sensitive traffic is likely to affect service quality if transmission is delayed.

To this end, it may be determined whether there is a predetermined type of traffic among the RB-allocated traffic (S430). In this case, the pre-designated type of traffic may be traffic that is sensitive to the delay time and the allowable waiting time should be shorter than the predetermined time. These types of traffic include Voice over LTE (VoLTE), SIBs (BCCH), Paging (PCCH), and the like. However, the present invention is not limited to this, and various kinds of traffic can be set as exceptions according to the administrator's setting.

Accordingly, if there is a traffic of the designated type among the traffic to which the RB is allocated (Yes in S430) as a result of the presence of the traffic of the designated type (S430), the RB- And deletes the transmitted traffic from the buffer (S440), and waits for the next TTI (S450).

Alternatively, if it is determined that there is no traffic of the designated type among the traffic allocated to the RB (S430: NO), the RB does not transmit the traffic allocated to the RB to the corresponding TTI And waits for the next TTI (S450). On the other hand, when the next TTI is reached, the step according to the embodiment of the present invention is performed again from the beginning (S410).

Meanwhile, FIG. 4 illustrates an exemplary embodiment of the present invention. For example, step S430 may be performed first from step S420.

As described above, according to the embodiment of the present invention, it is possible to increase the power saving effect of the base station by increasing the time for turning off the PA by collecting the delay tolerant traffic that is not sensitive to the delay time at the maximum, It may not affect the quality of the service that the user perceives by allowing the exceptionally immediate transmission of the delay sensitive service such as the voice over LTE (VoLTE).

FIG. 5 is a diagram illustrating experimental results of power consumption and PA off ratio when a conventional PA on / off technique and the present invention are applied to a base station.

Referring to FIG. 5, the power consumption of the base station is low when the PA on / off technique is used, and the power consumption is lower when the technique of the present invention is applied than when the PA on / off technique is used.

In addition, the rate at which the PA is turned off is always higher when the technique of the present invention is applied than when the conventional PA off technique is applied.

Therefore, by using the technique of the present invention, it is possible to increase the ratio of the time that the PA is turned off even during the daytime, so that the power consumption of the base station can be more effectively reduced.

The above-described embodiments of the present invention can be implemented by various means. For example, embodiments of the present invention may be implemented by hardware, firmware, software, or a combination thereof.

In the case of hardware implementation, the method according to embodiments of the present invention may be implemented in one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs) , FPGAs (Field Programmable Gate Arrays), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of an implementation by firmware or software, the method according to embodiments of the present invention may be implemented in the form of a module, a procedure or a function for performing the functions or operations described above. The software code can be stored in a memory unit and driven by the processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various well-known means.

Thus, those skilled in the art will appreciate that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

300: base station device
310: buffer
320: Scheduling unit
330:

Claims (7)

A method for transmitting traffic in a base station having a power amplifier (PA)
(a) a scheduling step of allocating an RB (Resource Block) to each of a plurality of traffic stored in a buffer when a TTI (Transmission Time Interval) arrives;
(b) determining whether the total number of RBs allocated to the traffic exceeds a predetermined threshold; and
(c) determining whether or not there is a predetermined type of traffic among the RB allocated traffic;
(d) waiting for the next transmission time interval (TTI) to arrive, and if the next TTI arrives, repeating the step (a)
Wherein the step (c) is performed when it is determined that the number of RBs allocated to traffic in the step (b) does not exceed a preset threshold value, and if the pre-designated type of traffic exists, Traffic is transmitted immediately,
The step (d) may be performed when it is determined that the traffic of the designated type is not present among the traffic allocated to the RB in step (c)
The PA is ON only when the transmission occurs,
The predetermined type of traffic is a traffic whose allowable waiting time is shorter than a predetermined time
A method for transmitting downlink traffic in a base station.
The method according to claim 1,
Before the step (d)
(e) transmitting the traffic allocated by the RB and removing the transmitted traffic from the buffer,
If the number of RBs allocated to the traffic in the step (b) is determined to exceed the predetermined threshold, or in the step (c), the step (e) Lt; RTI ID = 0.0 > traffic < / RTI >
A method for transmitting downlink traffic in a base station.
The method according to claim 1,
The step (a) may include scheduling according to priority information of the plurality of traffic
A method for transmitting downlink traffic in a base station.
delete A base station apparatus having a PA (Power Amplifier)
A buffer for storing traffic received from an external device,
A scheduler for allocating an RB (Resource Block) to each of a plurality of traffic stored in the buffer;
And a controller for determining whether the number of RBs allocated to the traffic exceeds a predetermined threshold value,
Wherein the controller allocates an RB to each of a plurality of traffic stored in the buffer through the scheduler whenever a TTI (Transmission Time Interval) arrives, and when the number of RBs allocated to the traffic does not exceed a preset threshold , It is determined whether or not traffic of a designated type is present among the traffic allocated to the RB, and if there is traffic of the predetermined type, the RB transmits traffic allocated thereto, If there is no RB, controls to wait for the next TTI (Transmission Time Interval) to come, and turns on the PA only when the transmission occurs,
The predetermined type of traffic is a traffic whose allowable waiting time is shorter than a predetermined time
Base station apparatus.
(a) a scheduling step of allocating an RB (Resource Block) to each of a plurality of traffic stored in a buffer when a TTI (Transmission Time Interval) arrives;
(b) determining whether the number of RBs allocated to the traffic exceeds a predetermined threshold; and
(c) determining whether or not there is a predetermined type of traffic among the RB allocated traffic;
(d) waiting for the next transmission time interval (TTI) to arrive, and if the next TTI arrives, repeating the step (a)
Wherein the step (c) is performed when it is determined that the number of RBs allocated to traffic in the step (b) does not exceed a preset threshold value, and if the pre-designated type of traffic exists, Traffic is transmitted immediately,
The step (d) is performed when it is determined that the traffic of the designated type is not present among the traffic allocated to the RB in step (c), and only when the transmission occurs, the power amplifier ) Is turned on,
The predetermined type of traffic is a traffic whose allowable waiting time is shorter than a predetermined time
A program stored in a computer-readable recording medium performing a downlink traffic transmission method of a base station.
And when executed on at least one processor, cause the processor to:
(a) When a TTI (Transmission Time Interval) arrives, an RB (Resource Block) is allocated to each of a plurality of traffic stored in a buffer,
(b) determine whether the number of RBs allocated to the traffic exceeds a predetermined threshold,
(c) causing the RB to determine whether or not a traffic of a designated type is present among the traffic allocated thereto,
(d) waiting for the next TTI (Transmission Time Interval) to come, and if the next TTI arrives, performing the operation again from the operation (a)
The operation (c) is performed when it is determined that the number of RBs allocated to the traffic in the operation (b) does not exceed a predetermined threshold, and when the RB is allocated To transmit traffic,
The operation (d) may be performed when it is determined that the traffic of the designated type is not present among the traffic allocated to the RB in the operation (c), and only when the transmission occurs, Amp; < / RTI >
The predetermined type of traffic is a traffic whose allowable waiting time is shorter than a predetermined time
A computer-readable recording medium having recorded thereon a program.

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