KR100802107B1 - Device and method for link balancing detection - Google Patents

Abstract

A link balance sensing device and a method thereof are provided to detect link balance of forward and reverse coverage through substantial forward power and reverse power in a usage region of a repeater including a base station, and to detect the link balance even without measurement with a measurement device in a substantial field, thereby efficiently operating a system. A link balance index calculator(160) calculates a link balance index produced by subtracting transmission power of a DPCCH(Dedicated Physical Control Channel) after closed loop power control from the first DPCCH power received from a base station in a terminal(100). A link balance state information provider(180) analyzes the link balance index to deliver balance state information of forward and reverse links.

Description

Device and Method for Link Balancing Detection

1 is a view for explaining a conventional power control method.

2 is a view for explaining a link balance detection method according to an embodiment of the present invention.

3 is a view for explaining the operating time of the first dedicated physical control channel power for the calculation of the forward link balance value and the dedicated physical control channel transmit power after the closed loop power control according to an embodiment of the present invention.

4 is a view for explaining a link balance detection apparatus according to an embodiment of the present invention.

5A and 5B illustrate a network state using a link balance index and a system information message according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: terminal 200: base station

300: base station controller 150: link balance sensing device

160: link balance index calculator 170: system information analysis unit

180: link balance status information providing unit

The present invention relates to a link balance detection device and a detection method thereof, and more particularly, to a link balance detection device and a detection method for detecting a balance of actual forward and reverse coverage in a use area such as a repeater including a base station. It is about.

In a mobile communication environment, multiple users share the same time and frequency, so that signals of other users act as interference. Therefore, the mobile communication environment allocates minimum power to each user, and adjusts power to satisfy call quality, which is called power control.

The mobile communication environment increases system capacity through power control, overcomes poor channel environments, and guarantees fairness of call quality between users (overcomes the near far problem).

1 is a view for explaining a conventional power control method.

Power control includes forward link power control and reverse link power control. Here, the forward power control is to adjust the amount of power transmitted from the base station 200 to the terminal 100, and the reverse power control, on the contrary, is based on the signal received from the base station 200. It is to control the size of the transmit power of.

The forward power control performed by the base station 200 is to change the forward transmission power of the base station 200 by using the reception state signal transmitted by the terminal 100 as a feedback using the signal received in the forward direction.

The reverse power control performed in the terminal 100 measures the energy of bit / noise of other signals (Eb / No) of the signal received from the terminal 100 in the base station 200 and compares it with a preset Eb / No threshold. , To transmit the control signal to change the reverse transmission power in the terminal (100).

Power control also includes open loop power control and closed loop power control, as shown in FIG.

Open Loop Power Control This is used when the terminal 100 determines the signal power to be transmitted in the reverse direction when a call is first started. That is, the terminal 100 is used when one transmission is composed of one message and one message. Open loop power control is performed under the assumption that the characteristics of the forward link and the reverse link will be similar, and the terminal receives a signal of a preset transmission power from the base station and sets the corresponding transmission power. In this case, since the flow of power control is not circulated, it is called open loop power control.

When the terminal 100 transmits a signal to the base station 200 after the closed loop power control is in a traffic state, the base station 200 compares the received signal with a preset threshold. Then, the base station repeats the command to adjust the transmission power level accordingly so that the flow of power control is circulated between the terminal 100, the base station 200, and the base station controller 300. Closed loop power control includes inner loop power control and outer loop power control.

Inner loop power control is to estimate the Eb / No of the signal received from the terminal 100 at the base station 200 and compare the Eb / No threshold to determine the power control signal.

The base station 200 evaluates the Eb / No of the signal received from the terminal 100, and transmits a power control command signal to the terminal 100 by comparing the evaluated Eb / No value with the Eb / No threshold value. The terminal 100 lowers the transmission power if the received Eb / No is greater than the preset power control Eb / No threshold value by the power control command signal, and vice versa.

Outer loop power control is to adjust the Eb / No threshold for power control in the base station 200 and the base station controller 300.

The base station controller 300 receives a traffic channel frame received from the terminal 100 at the base station 200. The base station controller 300 checks the frame error rate of the received traffic channel frame, and adjusts the transmission power of the terminal 100 by adjusting the power control Eb / No threshold accordingly.

For example, when the frame error rate of the traffic channel frame transmitted from the terminal 100 is high, the base station controller 300 transmits a control signal for raising the power control Eb / No threshold set by the base station. The base station 200 increases the power control Eb / No threshold, and if the Eb / No of the signal received from the terminal 100 is lower than the higher power control Eb / No threshold, increase the transmit power to the terminal 100. Transmits a control signal.

As described above, it is the outer loop power control that adjusts the power control Eb / No threshold which is preset for power control in the base station according to the change of the channel (propagation environment).

On the other hand, the balance of the forward and reverse coverage through the actual forward and reverse power in the use area, such as a remote radio head (RRH) or a repeater including a base station is referred to as link balancing (Link Balancing).

In the current WCDMA (Wide Code Division Multi Access) system, the terminal 100 does not have a special device for detecting link balance. In the CDMA system, the terminal 100 uses a Tx_Adj value using a regression constant. A rough link balance can be seen.

However, in case of WCDMA, the terminal 100 may calculate a path loss by detecting power of a common pilot channel (CPICH) transmitted from a base station through a system information block (SIB) # 3.

However, in the actual field (CP), in particular, the value of CPICH transmitted to the SIB through the repeater is operating inconsistent with the value transmitted through the antenna at each node.

In other words, the repeater often transmits higher or lower than the actual power due to the scalability of the coverage. For example, when a repeater is cascaded due to scalability, a gain value for forward power is set differently depending on how many repeaters are connected. Accordingly, the system operator can check the abnormal operation of the equipment or the transmission gain of the repeater through link balance.

However, in the Wide Code Division Multi Access (WCDMA) system, since the terminal 100 does not have a sensing device and a detection method for link balance, it is difficult to quickly verify the equipment in operation, and go to the site unconditionally for power. There is a problem that calibration must be performed.

Accordingly, the present invention is to solve the above problems, it is possible to detect the link balance for the forward and reverse coverage through the actual forward power and reverse power in the use area of the RRH / repeater, including the base station, the actual field In the present invention, there is provided a link balance sensing device capable of detecting link balance without measuring through a measuring device and a sensing method thereof.

In addition, an object of the present invention is to check the setup and calibration of the repeater, and to check the deterioration and path loss of the base station or repeater receiving end, and bears all data or AMR (Adaptive Multi-Rate) bearers. It is to provide a link balance detection device and a method of detecting the same, which can measure the power of the control panel, which enables easy operation and trouble shooting.

In addition, an object of the present invention is a transmission balance value (Tx_bal) using the difference between the transmission power initially set through the traffic channel and the actual closed loop power control, not the access channel. The present invention provides a link balance sensing device and a sensing method thereof that can be calculated and defined for at least transient coverage reduction or reduction.

Other objects of the present invention will be readily understood through the following description.

According to one aspect of the present invention, an apparatus for sensing a balance of forward and reverse links in a WCDMA system is disclosed.

An apparatus for detecting a link balance according to an embodiment of the present invention includes a link balance index calculation unit and a link balance index calculator for calculating a link balance index obtained by subtracting transmission power of a DPCCH after closed loop power control from initial DPCCH power received from a base station at a terminal. It may include a link balance state information providing unit for delivering the balance state information of the forward and reverse links by analyzing the index.

According to another aspect of the present invention, a method for detecting a balance of forward and reverse links in a WCDMA system is disclosed.

In a link balance sensing method according to an embodiment of the present invention, the method may include calculating an initial DPCCH power received from a base station, calculating a transmission power of a DPCCH after closed loop power control, and the closed loop power from the calculated initial DPDDH power. Calculating a link balance index obtained by subtracting the DPCCH transmission power after the control.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. It should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. In the following description of the present invention, when it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

FIG. 2 is a diagram illustrating a method for detecting a link balance according to an embodiment of the present invention, and FIG. 3 is an initial dedicated physical control channel power and closed loop for calculating a forward link balance value according to an embodiment of the present invention. It is a figure for demonstrating the operation time of the dedicated physical control channel transmission power after power control.

In the WCDMA system according to the present invention, a link balance index (Tx_bal) for detecting forward link balance detection is calculated.

First, in step S210, as shown in the following equation (1), the initial DPCCH power is calculated. In the WCDMA system, when the initial preamble is terminated and the synchronization procedure of the first layer is performed, the power of the first DPCCH becomes the initial power of the first traffic channel.

Initial DPCCH Power (DPCCH_init_Power) = DPCCH Power Offset Value (DPCCH_Power_offset)-UE Receive Pilot Signal Code Power (UE_PCPICH_RSCP)-Equation (1)

Here, the DPCCH_Power_offset value may be calculated as shown in Equation (2) below.

DPCCH_Power_offset = Eb / No-Processing gain + CPICH_TX_power + Uplink interference ---- Equation (2)

For example, in normal conditions at room temperature, the DPCCH_Power_offset value is 4dB (required Eb / No) at 4dB (based on 13.6k SRB), Processing gain is 24.5dB, CPICH_TX_power is 33dBm, and Uplink interference is -105.2dB. It can be calculated as + 33-105.2 = -92.7.

The uplink interference value can be calculated through the following equation (3).

Uplink interference value = Thermal noise density + 10log (chiprate) + Noise figure ---- Equation (3)

Since the link balance sensing device 150 (see FIG. 4) is mounted in the terminal 100, the DPCCH_Power_offset value and the UE_PCPICH_RSCP value transmitted from the terminal 100 in the RRC connection setup message are generally transmitted from the terminal 100. .

In step S220, the DPCCH power after closed loop power control for calculating the link balance index (Tx_bal) is calculated.

Referring to FIG. 3, in the WCDMA system, after setting an initial DPCCH power, a radio link recovery (RL restoration) is performed in the base station 200 after a dlTPC pattern. The WCDMA system then performs closed loop power control (power control preamble and signal radio bearer delay) and then measures the DPCCH power according to a set period and reports it to the base station.

The link balance sensing device 150 may calculate the DPCCH power after the closed loop power control by using the beta C (gain of control part) value and the beta D (gain of data part) value when setting up each bearer. In this case, even if the SRB is converted to SRB and RB (Radio Bearer) can be calculated through the calculation.

In case of DPCCH, it is a signal that should be maintained even if RB setup or RB reconfiguration is performed, and the power of DPDCH is calculated based on the power of DPCCH, so if the beta C value and beta D value of the bearer are known, DPCCH power Can be calculated.

Since the link balance sensing device 150 is installed in the terminal 100 to know the total transmission power of the terminal, the link balance sensing device 150 may be calculated by dividing the DPCCH power after the closed loop power control into two cases as follows.

1) When both DPDCH and DPCCH are required in the Transport Format Combination Indicator (TFCI)

Terminal total transmit power = DPCCH power + DPDCH power = DPCCH power * (1+ (beta D value / beta C value) ² ) --- Equation (4)

The DPDCH power link balance detection device 150 indicates that the DPDCH power after the closed loop power control = DPCCH power * (beta D value / beta C value) ² ---- Equation (5) Then, it can be obtained as follows.

DPCCH Power = (a * Beta C Value ² ) / (Beta D Value ² + Beta C Value ² ) ---- Formula (6)

2) Only DPCCH exists in TFCI

DPCCH power = terminal total transmit power ---- formula (7)

In operation S230, the link balance sensing apparatus 150 calculates the link balance index Tx_bal by subtracting the transmit power of the DPCCH after the closed loop power control from the initial DPCCH power DPCCH_init_Power using the following Equation (8). do.

Tx_bal = DPCCH_init_Power-DPCCH power after closed loop power control Equation (8) The link balance detection device 150 can determine the balance of the forward link using the calculated link balance index (Tx_bal). Using this, it is possible to check for deterioration and path loss of the base station or repeater receiver. A network state predictable using the link balance index Tx_bal will be described in more detail with reference to FIG. 5A.

In operation S240, the link balance sensing apparatus 150 determines a network state of the reverse link by analyzing a system information block (SIB) # 7, which is one of system information received by the terminal 100 to the base station 200.

 The base station 200 broadcasts Received Signal Strengh Indicator (RSSI) (UL interference) information to the terminal using SIB # 7, which is one of the system information. The link balance sensing apparatus 150 may analyze the SIB # 7 information received by the terminal 100 to determine the degree of degradation of the receiving end of the actual base station or repeater. In general, although the repetition period of the system information SIB varies depending on the manufacturer and the operator, most of the repetition cycles are operated at intervals of about 640 msec.

In operation S250, the link balance detecting apparatus 150 analyzes the calculated link balance index Tx_bal and the system information, and transmits the balance information of the forward link and the reverse link to the system operation server (not shown) through the base station controller 300. Can provide.

The base station controller 300 may perform efficient power control by adjusting the transmission gain of the base station 200 or the repeater using the received link balance state information.

In addition, the system operation server can check the repeater setup and calibration state and check the degradation and path loss of the base station 200 or the repeater receiving end by using the received link balance state information. It can be operated as a problem, and a trouble shooting is possible.

As described above, the link balance detection method according to the present invention may be implemented as a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a computer-readable form. .

4 is a block diagram illustrating an apparatus for detecting a link balance according to an embodiment of the present invention.

Referring to FIG. 4, the link balance sensing device 150 includes a link balance index calculator 160, a system information analyzer 170, and a link balance state information provider 180.

The link balance sensing device 150 according to the present invention may be mounted in the terminal 100 or a mobile communication system.

As shown in Equation (8), the link balance index calculator 160 calculates a link balance index (Tx_bal) by subtracting the transmission power (DPCCH power) of the DPCCH after the closed loop power control from the initial DPCCH power (DPCCH_init_Power). do.

The link balance index calculator 160 calculates the initial DPCCH power using the above-described equations (1) to (3) to calculate the link balance index. The link balance index calculator 160 may calculate the initial DPCCH power using the DPCCH_Power_offset value and the UE_PCPICH_RSCP value transmitted from the terminal 100 to the base station 200 in the RRC connection setup message.

The link balance index calculator 160 calculates the DPCCH power after the closed loop power control by using Equations (4) to (7) described above. The link balance index calculator 160 may calculate the DPCCH power when both the DPDCH and the DPCCH are present in the TFCI and when there is only the DPCCH in the TFCI using the total transmission power of the terminal.

The system information analyzer 170 receives a system information block (SIB) # 7, which is one of system information received from the base station 200, from the terminal 100, and analyzes the network information of the reverse link. The system information analyzer 170 analyzes Received Signal Strengh Indicator (RSSI) information using SIB # 7, which is one of the system information, to receive the actual base station or repeater. The degree of deterioration of the stage can be determined.

The link balance state information providing unit 180 analyzes the calculated link balance index (Tx_bal) and system information to provide the balance information of the forward link and the reverse link to the system operation server (not shown) through the base station controller 300. Can be. The base station controller 300 may perform efficient power control by adjusting the transmission gain of the base station 200 or the repeater using the received link balance state information, and the system operation server may set up the repeater using the received link balance state information. It is possible to check the setup and calibration status and to check the degradation and path loss of the base station 200 or the repeater receiver so that the system can be operated efficiently.

5A and 5B are diagrams for describing a network state using a link balance index and a system information message according to an embodiment of the present invention.

As shown in FIG. 5A, the system operation server may receive forward link balance state information corresponding to link balance index information from the link balance sensing device 150. A link balance index of 0 is the most ideal case, and the link balance index can be divided into a case where the link balance index is greater than 0 and a case where the network state can be predicted as shown in FIG. 5A.

If the link balance index is greater than 0, the forward link power is small in link balancing. In this case, the network state is likely to degrade the base station transmitter end, and the repeater forward gain is likely to be low.

If the link balance index is less than 0, the forward link power is large in link balancing. In this case, the network state is likely to be overtransmitted by the base station, and the repeater forward gain is likely to be large.

Also, as shown in FIG. 5B, the system operation server may receive reverse link balance state information provided by analyzing system information from the link balance sensing device 150. Here, the link balance sensing device 150 analyzes Received Signal Strength Indicator (RSSI) information using UL SIB # 7, which is one of system information.

When the uplink interference value is calculated based on Equation (3) described above, there may be a difference depending on the mobile communication system, and thus may be preset. The uplink interference value can be preset by inferring about -105dBm in general, for example, and it is difficult to determine the quantitative value due to measurement error.However, when the system operation is much larger than most values, It can be judged that there is an abnormality.

If the uplink interference (UL interference) is greater than a predetermined value, the reverse link power is small, in this case, the network state is likely to deteriorate the base station receiving end, the repeater receiving end deterioration is likely.

If the uplink interference (UL interference) is less than a predetermined value, the reverse link power is large, in which case the network state is likely to be excessive base station reception gain.

As described above, the present invention can detect the link balance for the forward and reverse coverage through the actual forward power and the reverse power in the use area, such as the RRH / repeater including the base station, and do not measure through the measurement equipment in the actual field There is an advantage in that it is possible to detect link balance.

In addition, the present invention is capable of checking the setup and calibration of the repeater and the deterioration and path loss of the base station or repeater receiver, and the data or adaptive multi-rate (AMR) for all bearers. The power can be measured for the system to operate efficiently.

In addition, the present invention calculates the transmission balance value (Tx_bal) using the difference between the transmission power initially set through the traffic channel rather than the access channel and the transmission power when the actual closed loop power control is performed. At the very least, there is an advantage that can be defined for transient or reduction of forward coverage.

In the above described in detail through an embodiment of the knowledge management system according to the present invention, the content is not limited to the field of the invention described in the claims below. In addition, in the art, it will be apparent to those skilled in the art that various changes or modifications are made within the scope of the present invention.

Claims (8)

An apparatus for detecting a balance of forward and reverse links in a WCDMA system, A link balance index calculator for calculating a link balance index obtained by subtracting the transmit power of the DPCCH after the closed loop power control from the initial DPCCH power received from the base station by the terminal; And a link balance state information providing unit for analyzing the link balance index and delivering balance state information of the forward and reverse links. The method of claim 1, And a system information analyzer for receiving and analyzing system information block (SIB) information, which is system information received from a base station, to determine a network state of a reverse link. The method of claim 1, The link balance detection device And a balance balancing information of the forward and reverse links to the base station mounted in the terminal. In the method for detecting the balance of the forward and reverse links in the WCDMA system, Calculating initial DPCCH power received from the base station; Calculating the transmit power of the DPCCH after closed loop power control; And Calculating a link balance index obtained by subtracting the DPCCH transmit power after the closed loop power control from the calculated initial DPDDH power. The method of claim 4, wherein And receiving system information block (SIB) information, which is system information received from a base station, and analyzing the SIB information to determine a network state of a reverse link. The method of claim 5, And transmitting balance state information of the forward and reverse links to a base station by using the link balance index and the determined network state of the reverse link. The method of claim 6, And the base station transmits the received balance state information of the forward and reverse links to a system operation server. A recording medium readable by an electronic device on which a program comprising typed instructions for executing a method of detecting a balance of forward and reverse links in a WCDMA system, comprising: Calculating initial DPCCH power received from the base station; Calculating the transmit power of the DPCCH after closed loop power control; And And calculating a link balance index obtained by subtracting the DPCCH transmit power after the closed loop power control from the calculated initial DPDDH power.

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