KR101448981B1 - A transmitter-receiver of base station with array antenna and method for forming beam - Google Patents

Abstract

The present invention relates to a base station transceiver having a plurality of antennas, comprising: a plurality of RF units that are mapped with respective antennas and convert signals received through an antenna to a baseband digital signal; Determining an inner product of the estimated first direction vector and a previously determined second direction vector to determine a direction vector for beam forming according to the inner product value, and transmitting the determined direction vector to the RF And a demodulator for demodulating a signal output from the beam former, wherein a propagation direction which is completely different from a moving direction of the mobile station is formed, or a scattering of a radio wave and reflection Even in a channel environment in which the phenomenon that the direction of arrival of the radio wave is very deeply spread occurs temporarily It is possible to perform the beam forming of the user direction may continuously keep a communication quality, regardless of the channel environment changes.

Beam, array antenna, smart antenna, direction vector

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station transceiver and a beam forming method using an array antenna,

The present invention relates to a base station transceiver apparatus and a beam forming method provided with an array antenna, and more particularly, to a base station transceiver apparatus and a beam forming method using a plurality of antennas, Determining an inner product of a vector and a second direction vector determined in a previous direction vector estimation period, determining a direction vector for beam formation according to the obtained inner product value, and performing beamforming of the uplink or downlink using the determined direction vector To a base station transceiver and a beam forming method having an array antenna.

The smart antenna is composed of an array antenna and can actively change the radiation pattern of the array antenna in response to the direction of propagation in which the power or signal-to-noise ratio of the received signal is increased. Thus, a beam having the optimum directivity toward the propagation direction from the desired terminal Can be formed.

The smart antenna has a switched beam smart antenna and an adaptive beam smart antenna according to a beamforming method.

In the switched beam smart antenna, the pattern of the antenna is fixed. In the adaptive beam smart antenna, the pattern of the antenna may change according to the time or the surrounding environment. Compared to the fixed beam, It has the advantage of being able to adapt to the environment more intelligently.

1 is a flow chart illustrating a method of forming a beam in a conventional adaptive beam smart antenna system.

Referring to FIG. 1, the adaptive beam smart antenna system estimates a direction vector of a beamformer using signals received by the respective array antennas (S100).

Then, the adaptive beam smart antenna system multiplies the received signal by the estimated direction vector, thereby receiving only the signal from the desired direction, and performs beam forming to remove the signal from the unwanted direction (S102) Demodulation is performed in the user's modem (S104).

In the downlink, a signal is transmitted in the corresponding direction using the currently estimated direction vector, so that the signal is transmitted only in the direction of the desired user.

However, since the conventional smart antenna system performs beam forming only in the estimated direction, if the estimated direction vector is different from the direction in which the signal is actually received, performance degradation due to beam formation occurs.

Further, in the mobile channel environment, the wireless channel environment continuously changes due to the movement of the vehicle or the user and the change of the surrounding environment. In this particular case of the change of the mobile channel environment, a propagation direction completely different from the moving direction of the mobile terminal is formed, or a propagation direction of the radio wave is spread very seriously due to scattering and reflection of the severe radio wave. If the smart antenna system estimates the direction vector at the time of the transient sudden propagation environment change and applies the value to the beam formation, the signal is not transmitted in the direction of the desired user, .

It is an object of the present invention to provide a radio communication method and a radio communication method in which a phenomenon in which a propagation direction of a radio wave is very seriously spread due to scattering and reflection of a deep radio wave, The present invention also provides a base station transceiver apparatus and a beam forming method having an array antenna capable of performing beamforming.

It is another object of the present invention to provide a base station transceiver and a beam forming method provided with an array antenna capable of actively tracking a beam direction according to a propagation angle of a received signal in an adaptive beam smart antenna system of a mobile communication equipment station.

It is another object of the present invention to provide a base station transmission / reception system having an array antenna capable of solving the problem of call quality that may occur when a beam is temporarily formed in a wrong direction in a channel environment in which a beam direction is abruptly changed in a mobile radio channel environment Apparatus and beam forming method.

It is a further object of the present invention to provide a method and apparatus for controlling a beam direction of a smart antenna, in which a sudden change in beam direction occurs during a short period of time, And determining whether to perform beamforming in a new direction in consideration of the change in the beam direction having a high correlation with the beamforming method.

According to an aspect of the present invention, there is provided a base station transceiver having a plurality of antennas, including: a plurality of RF units mapped with respective antennas to convert signals received through antennas into baseband digital signals; A first direction vector is estimated using a plurality of signals output from each RF unit, an inner product of the estimated first direction vector and a previously determined second direction vector is obtained, and a direction vector And a modem for demodulating a signal output from the beamformer, the base station transmitting / receiving apparatus comprising: a base station transmitting / receiving apparatus having a base station do.

The beamformer forms a beam by applying the determined direction vector to a signal to be transmitted for each mobile terminal, and outputs the beam as a forward link.

Wherein the beam former compares the inner product values of the first direction vector and the second direction vector with a threshold value to determine a first direction vector as a direction vector for beam formation when the inner product value is equal to or greater than a threshold value, Estimating a direction vector using a received signal during a predetermined number of direction vector estimation periods while maintaining a beam direction by the second direction vector, and when the estimated direction vector corresponds to the first direction vector, One direction vector is determined as a direction vector for beam formation.

Wherein the beam former compares the inner product values of the first direction vector and the second direction vector with a threshold value to determine a first direction vector as a direction vector for beam formation when the inner product value is equal to or greater than a threshold value, The inner product of the first direction vector and the direction vectors determined during the previous predetermined period is obtained, and the direction vector having the maximum inner product is determined as the direction vector for beam forming.

Wherein the beam former compares the inner product values of the first direction vector and the second direction vector with a threshold value to determine a first direction vector as a direction vector for beam formation when the inner product value is equal to or greater than a threshold value, A third direction vector is obtained by applying a weight to each of the first direction vector and the second direction vector, and the third direction vector is determined as a direction vector for beam formation.

The beamformer performs beamforming by multiplying each signal output from each RF unit by the determined direction vector to receive a signal from a desired direction and to remove a signal from an undesired direction.

According to another aspect of the present invention, there is provided a beamformer of a base station including an array antenna, the beamformer including: a direction vector estimating unit that estimates a first direction vector using a plurality of signals received through a plurality of antennas; A direction vector determination unit for determining an inner product of a first direction vector estimated in the previous direction vector estimation cycle and a second direction vector determined in the previous direction vector estimation cycle and determining a direction vector for beam formation according to the obtained inner product value, There is provided a beamformer of a base station including an array antenna including a beamformer for performing beamforming of an uplink or an uplink using a determined direction vector.

The direction vector estimator estimates a direction vector using one of MUSIC, ESPRIT, an eigenvector of a covariance matrix of a received signal, a pilot assisted method, and an MMSE method using a pilot signal.

The direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value, and determines the first direction vector as a direction vector for beam formation when the inner product value is equal to or greater than the threshold value.

Wherein the direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value, and when the inner product value is not equal to or greater than the threshold value, the direction vector determination unit maintains the beam direction by the second direction vector, Estimates a direction vector using a received signal during a direction vector estimation period, and determines the first direction vector as a direction vector for beamforming when the estimated direction vector corresponds to the first direction vector.

The direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value, and if the inner product value is not equal to or greater than the threshold value, the inner product of the first direction vector and the direction vectors determined during the previous predetermined period Respectively, and determines a direction vector having the maximum inner product as a direction vector for beam formation.

The direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value and applies a weight to each of the first direction vector and the second direction vector when the inner product value is not equal to or greater than the threshold value, The direction vector is determined, and the third direction vector is determined as a direction vector for beam formation.

The beam forming unit includes a plurality of multipliers for multiplying each signal received through each antenna by a direction vector determined by the direction vector determiner, and a plurality of signals output from the multipliers are combined to output a signal in a desired direction .

According to another aspect of the present invention, there is provided a base station transceiver apparatus including an array antenna, the method comprising: (a) estimating a first direction vector using a signal received through a plurality of antennas; (B) obtaining an inner product of the estimated first direction vector and a second direction vector determined in a previous direction vector estimation cycle, (c) comparing the obtained inner product value with a predetermined threshold value, and (C) comparing the determined inner product value with a predetermined threshold value to determine whether the inner product value is greater than or equal to a threshold value, (d) comparing the inner product value with a predetermined threshold value, If the inner product value is not equal to or greater than the threshold value, the direction vector is added using the received signal during a predetermined predetermined number of direction vector estimation periods while maintaining the beam direction by the second direction vector. And determining the first direction vector as a direction vector for beamforming when the estimated direction vector corresponds to the first direction vector, the beamforming method of the base station transceiver apparatus including the array antenna is provided .

And performing an uplink or downlink beamforming using the determined direction vector. The beamforming method of the base station transmitting / receiving apparatus includes an array antenna.

And determining the direction vector as a direction vector for beam formation when the inner product value is equal to or greater than the threshold value as a result of the determining in step (c), the method further comprising: .

According to another aspect of the present invention, there is provided a base station transceiver apparatus including an array antenna, the method comprising: (a) estimating a first direction vector using a signal received through a plurality of antennas; (B) obtaining an inner product of the estimated first direction vector and a previously estimated second direction vector; (c) comparing the determined inner product value with a predetermined threshold value to determine whether the inner product value is greater than or equal to a threshold value (D) obtaining an inner product of a first direction vector and a direction vector for a previous predetermined period when the inner product value is not equal to or greater than the threshold value as a result of the determining in step (c), (e) ) Determining a direction vector having a maximum value among the obtained inner product values as a direction vector for beamforming is provided.

And performing an uplink or downlink beamforming using the determined direction vector. The beamforming method of the base station transmitting / receiving apparatus includes an array antenna.

Further comprising the step of determining the first direction vector as a direction vector for beamforming if the inner product value is greater than or equal to a threshold value as a result of the determining in step (c) A beam forming method is provided.

And storing the determined direction vector for beamforming as a previous direction vector value. The beamforming method of a base station transceiver including an array antenna is provided.

According to another aspect of the present invention, there is provided a base station transceiver apparatus including an array antenna, the method comprising: (a) estimating a first direction vector using a signal received through a plurality of antennas; (B) obtaining an inner product of the estimated first direction vector and a previously estimated second direction vector; (c) comparing the determined inner product value with a predetermined threshold value to determine whether the inner product value is greater than or equal to a threshold value (D) if the inner product value is not equal to or greater than the threshold value as a result of the determining in step (c), the first direction vector and the second direction vector are multiplied by weights to obtain a third direction vector, And determining the third direction vector as a direction vector for beamforming. A method for beamforming a base station transceiver apparatus having an array antenna is provided.

As described above, according to the present invention, even in a channel environment in which a phenomenon that a propagation direction of a radio wave completely differs from a moving direction of a mobile station is formed, or a propagation direction of a radio wave is extremely spread due to scattering and reflection of a strong radio wave, It is possible to provide a base station transceiver and a beam forming method having an array antenna capable of continuously maintaining communication quality irrespective of a change in a channel environment.

Also, it is possible to provide a base station transceiver and a beam forming method provided with an array antenna capable of actively tracking a beam direction according to a propagation angle of a received signal in an adaptive beam smart antenna system of a mobile communication equipment station.

Also, a base station transmitting and receiving apparatus and a beam forming method provided with an array antenna capable of solving a problem of a communication quality that may occur when a beam is temporarily formed in a wrong direction in a channel environment in which a beam direction is abruptly changed in a mobile radio channel environment Can be provided.

In addition, it is considered that temporal phenomenon in which a sudden change in beam direction occurs during a short time during beam forming of a smart antenna, and thus, maintaining the previous beam direction will help maintain the quality of the signal, The base station transmitting and receiving apparatus and the beam forming method provided with the array antenna for determining whether beam forming should be performed in a new direction in consideration of the change of the direction.

In addition, beamforming is performed only in a direction of a desired user in a downlink using information of a direction vector estimated in the uplink, thereby increasing a communication radius and reducing a multipath interference and a multipath signal, It is possible to provide a base station transceiver and a beam forming method provided with an array antenna capable of high-speed data communication with a lower BER at a wider communication radius in mobile communication by increasing the interference and noise ratio.

The foregoing and other objects, features, and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

2 is a block diagram illustrating a base station transceiver having an array antenna according to the present invention.

2, a base station transceiver apparatus having an array antenna includes an RF unit 200 configured by a number corresponding to each of a plurality of antennas and converting a signal received through each antenna into a baseband digital signal, A beamformer 300 for determining a direction vector for beamforming using a signal output from the RF unit 200 and applying the determined direction vector to a signal output from the RF unit 200 to perform beamforming, And a modem 400 for demodulating a signal output from the beam former 300. [

The plurality of antennas are array antennas, and receive signals transmitted from the mobile terminal or transmit signals to the mobile terminal.

The RF unit 200 transmits and receives a radio signal to and from a mobile terminal.

The RF unit 200 includes an intermediate frequency (IF) processor 202 for converting the radio signals received through the respective antennas into intermediate frequency signals, and an analog-to-digital converter -Digital) converter 204. [0031]

The beamformer 300 estimates a first direction vector using a signal output from each RF unit 200, obtains an inner product of the estimated first direction vector and a previously estimated second direction vector, The direction vector for beam formation is determined according to the value.

The beamformer 300 determines a direction vector for beamforming in a beam direction vector estimation period, stores the determined direction vector, and uses the direction vector to determine a direction vector in a subsequent beam direction vector estimation period.

That is, the beamformer 300 estimates a first direction vector using a signal output from each RF unit 200, and obtains an inner product of the estimated first direction vector and the immediately-determined second direction vector . Then, the beam former 300 compares the obtained inner product value with a predetermined threshold value, and determines the first direction vector as a direction vector for beam formation when the inner product value is equal to or greater than the threshold value.

If the inner product value is not equal to or greater than a predetermined threshold value, the beam former 300 determines the second direction vector determined before the estimation of the first direction vector as a direction vector for beam formation.

If the inner product of the first direction vector and the second direction vector is not equal to or greater than the threshold value, the beam former 300 obtains the inner product of the first direction vector and the direction vectors for the previous predetermined period, In direction vector is determined as a direction vector for beam formation.

이고, 이전 일정 주기 동안에 결정된 방향벡터가

,

,

,

인 경우, 상기 빔 형성기(300)는

과 이전의 방향벡터

,

,

,

에 대해 각각 내적을 구한다. 즉, 상기 빔 형성기(300)는

과

과의 제1 내적,

과

과의 제2 내적,

과

와의 제3 내적,

과

과의 제4 내적을 각각 구하고, 그 구해진 제1 내적 내지 제4 내적중에서 그 값이 최대인 방향벡터를 빔 형성을 위한 방향벡터로 결정한 다. 제1 내지 제4 내적중에서 제3 내적값이 최대라면, 상기 빔 형성기(300)는

을 빔 형성을 위한 방향벡터로 결정한다.For example, if the newly estimated first direction vector is

, And the direction vector determined during the previous periodic period is

,

,

,

, The beam former 300 may be a

And the previous direction vector

,

,

,

Respectively. That is, the beam former 300

and

The first internal,

and

The second internal,

and

The third internal,

and

Respectively, and a direction vector having the largest value among the obtained first to fourth inner products is determined as a direction vector for beam formation. If the third inner value among the first through fourth inner products is the maximum, the beam former 300

As a direction vector for beam forming.

If the inner product of the first direction vector and the second direction vector is not equal to or greater than the threshold value, the beamformer 300 obtains a third direction vector by applying a weight to each of the first direction vector and the second direction vector, And determines the third direction vector as a direction vector for beam formation.

Also, the beamformer 300 performs beamforming of the uplink or downlink using the determined direction vector.

That is, the beamformer 300 multiplies each signal output from each RF unit 200 by the determined direction vector to receive a signal from a desired direction, and performs beamforming to remove a signal from an undesired direction.

In addition, the beamformer 300 applies the determined direction vector to a signal to be transmitted for each mobile terminal, so that a signal is transmitted in a corresponding direction, and a signal is transmitted only in a direction of a desired user.

A detailed description of the beam former 300 that performs the above-mentioned functions will be described with reference to FIG.

FIG. 3 is a block diagram schematically illustrating the configuration of the beam shaper shown in FIG. 2 according to the present invention.

Referring to FIG. 3, the beamformer 300 includes a direction vector estimator 310 for estimating a first direction vector using a signal received through a plurality of antennas, A direction vector determiner 320 for obtaining an inner product of a first direction vector and a second direction vector determined in a previous direction vector determination period and determining a direction vector for beam formation according to the inner product value, And a beamformer 330 for applying a direction vector determined by the direction vector determiner to the signal to perform beamforming.

The direction vector estimator 310 estimates a first direction vector using one of MUSIC, ESPRIT, an eigenvector of a covariance matrix of a received signal, a pilot assisted method, and an MMSE method using a pilot signal.

The direction vector determination unit 320 determines a moving direction of the mobile terminal based on the first direction vector estimated by the direction vector estimation unit 310 and the beam direction vector (second direction vector) . This is because the direction of the received user signal does not change significantly when the beamforming is performed for a short period (e.g., 1 ms, 5 ms, or 10 ms). If the currently estimated first direction vector is significantly different from the second direction vector, this may be caused by the fact that the current mobile channel environment is largely changed due to a change of the mobile channel environment, and the presently received signal may be distorted due to fading or the like have.

In addition, the direction vector determination unit 320 uses the inner product of the two direction vectors as shown in Equation (1) to determine whether the currently estimated first direction vector is similar to the beam direction of the second direction vector.

와

사이의 각이다. Here, | · | Is, the size of, θ the two vectors

Wow

Respectively.

If the magnitude of the direction vector is normalized in Equation (1), the inner product of the two direction vectors is expressed by Equation (2).

Therefore, when the similarity between the beam direction of the currently estimated signal and the previously estimated beam direction is determined using the inner product, if both direction vectors are normalized and there is no change in direction, the inner product is 1 if it is the same direction vector, The more the variation of the direction is, the smaller the value of the inner product becomes.

)과 비교한다.Therefore, the direction vector determination unit 320 estimates how much the currently estimated first direction vector is different from the second direction vector that was determined immediately before using the inner product, and then, the estimated inner product value is estimated by the following equation 3, the threshold value

).

Here, c _r is a threshold value. If this value is close to 1, it indicates that there is no large change with the second direction vector that was estimated immediately before the currently estimated first direction vector. If this value becomes smaller than 1, Indicates that the first direction vector has changed significantly compared to the second direction vector that was estimated just before.

The direction vector determination unit 320 compares the inner product values of the first direction vector and the second direction vector with a threshold value. If the inner product value is equal to or greater than a threshold value, the first direction vector is used as a direction vector for beam formation .

If the inner product value of the first direction vector and the second direction vector is not equal to or greater than the threshold value as a result of comparing the inner product value of the first direction vector with the threshold value, As a direction vector.

If the inner product value of the first direction vector and the second direction vector is not equal to or greater than the threshold value as a result of the comparison between the inner product value and the threshold value, the direction vector determination unit 320 determines And the inner product with the direction vectors are respectively obtained, and a direction vector having the maximum inner product is determined as a direction vector for beam formation.

If the inner product value of the first direction vector and the second direction vector is not equal to or greater than the threshold value as a result of comparing the inner product value and the threshold value of the second direction vector, the direction vector determination unit 320 determines that the first direction vector and the second direction vector To obtain a third direction vector, and determines the third direction vector as a direction vector for beam formation.

The beamformer 330 performs beamforming of the uplink or downlink using the direction vector determined by the direction vector determiner 320. [

The beam forming unit 330 performs a plurality of multipliers 332a, 332b, 332n, and 332n that multiply the signals received through the respective antennas by the direction vector determined by the direction vector determining unit. And an adder 334 which combines a plurality of signals output from the multiplier 332 and outputs a signal in a desired direction.

4 is a flowchart illustrating a beam forming method of a base station transceiver including an array antenna according to an embodiment of the present invention.

Referring to FIG. 4, the beam former estimates a first direction vector using a signal received through a plurality of antennas (S400).

That is, the beam former estimates a first direction vector using MUSIC, ESPRIT, a method using an eigenvector of a covariance matrix of a received signal, a pilot assisted method, an MMSE method using a pilot signal, and the like.

Then, the beamformer obtains an inner product of the estimated first direction vector and a previously determined second direction vector to estimate a moving range of the corresponding mobile terminal (S402), compares the obtained inner product value with a predetermined threshold value (S404). The beam former compares the obtained inner product value with a predetermined threshold value to evaluate the reliability of the estimated first direction vector.

If it is determined in step S404 that the inner product value is greater than or equal to the threshold value, the beamformer determines the first direction vector as a direction vector for beamforming in step S406. Beam forming is performed (S408).

That is, if the inner product value is larger than the threshold value, since the movement of the user is similar to the actual environment for a short time in estimating a new beam forming direction vector, the beamforming is performed using the currently estimated direction vector .

If it is determined in step S404 that the inner product value is not equal to or greater than the threshold value, the beam former maintains the beam direction by the second direction vector (S408) The direction vector is estimated (S410).

Then, the beamformer determines whether the direction vector estimated in S410 corresponds to the first direction vector (S412).

If it is determined in step S412 that the estimated direction vector corresponds to the first direction vector, the beamformer performs step S406, and if not, performs step S400.

That is, if the inner product value is not equal to or greater than the threshold value, fading may occur due to a sudden change to an NLOS environment in a line-of-sight communication environment, or a direction vector estimated by a currently- It is determined that the beamforming reliability is degraded if the beamforming is performed using only the currently estimated direction vector. Instead of applying the new direction vector, a plurality of direction vector calculation cycles If a direction vector in the corresponding direction is also obtained, then this direction vector is applied. It is up to the system operator to decide how many times to wait for an incoming cycle.

5 is a flowchart illustrating a beam forming method of a base transceiver station including an array antenna according to another embodiment of the present invention.

Referring to FIG. 5, the beam former estimates a first direction vector using a signal received through a plurality of antennas (S500).

Then, the beamformer obtains an inner product of the estimated first direction vector and a previously estimated second direction vector to estimate a moving range of the corresponding user (S502), compares the obtained inner product value with a predetermined threshold value And determines whether the inner product value is equal to or greater than a threshold value (S504).

If it is determined in step S504 that the inner product value is greater than or equal to the threshold value, the beamformer determines the first direction vector as a direction vector for beamforming (S506), and transmits the uplink or downlink Beam forming is performed (S508).

If it is determined in step S504 that the inner product value is not equal to or greater than the threshold value, the beamformer obtains the inner product of the first direction vector and the direction vectors in the previous direction vector calculation period (S510).

Then, the beamformer determines a direction vector having the maximum value among the obtained inner product values as a direction vector for beamforming (S512), and performs beamforming of the uplink or the downlink using the determined direction vector And stores it as the previous direction vector value (S514).

That is, the beam former compares the newly estimated first direction vector with the previously estimated direction vector in the beam direction vector estimation period, updates the newly estimated direction vector with a difference of more than a predetermined value The beam direction is formed by a recent direction vector which is not different from a previously estimated direction vector by a predetermined value or more.

6 is a flowchart illustrating a beam forming method of a base station transceiver apparatus having an array antenna according to another embodiment of the present invention.

Referring to FIG. 6, the beam former estimates a first direction vector using a signal received through a plurality of antennas (S600).

Then, the beamformer obtains an inner product of the estimated first direction vector and a previously estimated second direction vector to estimate a moving range of the user (S602), compares the obtained inner product value with a predetermined threshold value And determines whether the inner product value is equal to or greater than a threshold value (S604).

If it is determined in step S604 that the inner product value is greater than or equal to the threshold value, the beamformer determines the first direction vector to be a direction vector for beamforming (S606), and transmits the uplink or downlink Beam forming is performed (S608).

If it is determined in step S604 that the inner product value is not equal to or greater than the threshold value, the beam former multiplies the first direction vector and the second direction vector by a weight, and then adds the third direction vector to obtain a third direction vector (S610). Here, the weights multiplied by the first direction vector and the second direction vector may be different values.

After performing step S610, the beamformer determines the third direction vector as a direction vector for beamforming (S612), and performs beamforming of the uplink or the downlink using the determined third direction vector S614). At this time, the beam former stores the determined third direction vector as a direction vector value immediately before.

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.

As described above, the base station transceiver and the beam forming method provided with the array antenna according to the present invention can improve the quality of a call that may occur when a beam is temporarily formed in a wrong direction in a channel environment in which a beam direction is drastically changed in a mobile radio channel environment, Is suitable for a technique capable of solving the problem of.

1 is a flow chart illustrating a method of forming a beam in a conventional adaptive beam smart antenna system;

2 is a block diagram illustrating a base station transceiver having an array antenna according to the present invention.

3 is a block diagram schematically showing the configuration of the beam shaper shown in Fig. 2 according to the present invention.

4 to 6 are flowcharts illustrating a beam forming method of a base station transceiver apparatus having an array antenna according to an embodiment of the present invention.

Description of the Related Art

200: RF section 202: IF processing section

204: ADC 300: Beamformer

310: direction vector estimation unit 320: direction vector determination unit

330: beam forming unit 332:

334: adder 340: storage unit

Claims (17)

A base station transceiver comprising a plurality of antennas, A plurality of RF units that are mapped with respective antennas and convert signals received through the antenna into baseband digital signals; A first direction vector is estimated using a plurality of signals output from each RF unit, an inner product of the estimated first direction vector and a previously determined second direction vector is obtained, and a direction vector And a beamformer for performing beamforming by applying the determined direction vector to a signal output from the RF unit, A modem for demodulating a signal output from the beam former; / RTI > The beam former includes: Wherein the first direction vector is determined as a direction vector for beam formation when the inner product value of the first direction vector and the second direction vector is compared with a threshold value and the inner product value is greater than or equal to a threshold value. Base station transmitting / receiving apparatus. The method according to claim 1, Wherein the beamformer forms a beam by applying the determined direction vector to a signal to be transmitted for each mobile terminal and outputs the beam as a forward link. The method according to claim 1, Wherein the beamformer performs beamforming by multiplying each signal output from each RF unit by the determined direction vector to receive a signal from a desired direction and to remove a signal from an undesired direction / RTI > A beamformer of a base station having an array antenna, A direction vector estimator for estimating a first direction vector using a plurality of signals received through a plurality of antennas; A direction vector determination unit for obtaining an inner product of a first direction vector estimated by the direction vector estimation unit and a second direction vector determined at a previous direction vector determination period and determining a direction vector for beam formation according to the obtained inner product value; A beamformer for performing beamforming of the uplink or downlink using the direction vector determined by the direction vector determiner; / RTI > Wherein the direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value and determines the first direction vector as a direction vector for beam formation when the inner product value is equal to or greater than a threshold value The beamformer comprising: an array antenna; 5. The method of claim 4, Wherein the direction vector estimator estimates a direction vector using one of MUSIC, ESPRIT, an eigenvector of a covariance matrix of a received signal, a pilot assisted method, and an MMSE method using a pilot signal. delete 5. The method of claim 4, Wherein the direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value, and when the inner product value is not equal to or greater than the threshold value, the direction vector determination unit maintains the beam direction by the second direction vector, Estimating a direction vector using a received signal during a direction vector estimation period, and determining the first direction vector as a direction vector for beamforming when the estimated direction vector corresponds to the first direction vector. A beamformer of a base station equipped with an antenna. 5. The method of claim 4, The direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value, and if the inner product value is not equal to or greater than the threshold value, the inner product of the first direction vector and the direction vectors determined during the previous predetermined period And determines a direction vector having a maximum inner product as a direction vector for beam forming. 5. The method of claim 4, The direction vector determination unit compares the inner product values of the first direction vector and the second direction vector with a threshold value and applies a weight to each of the first direction vector and the second direction vector when the inner product value is not equal to or greater than the threshold value, And the third direction vector is determined as a direction vector for beam forming. 5. The method of claim 4, Wherein the beam forming unit includes: a plurality of multipliers for multiplying each signal received through each antenna by a direction vector determined by the direction vector determining unit; And an adder for combining the plurality of signals output from the multipliers and outputting a signal in a desired direction. A base station transceiver having an array antenna is a method for forming an uplink or downlink beam, (a) estimating a first direction vector using a signal received through a plurality of antennas; (b) obtaining an inner product of the estimated first direction vector and a second direction vector determined in a previous direction vector determination period; (c) comparing the obtained inner product value with a predetermined threshold value to determine whether the inner product value is equal to or greater than a threshold value; and (d) determining the first direction vector as a direction vector for beam forming if the inner product value is greater than or equal to a threshold value as a result of the determining in step (c) Wherein the base station transmitter and receiver includes an array antenna. 12. The method of claim 11, And performing uplink or downlink beamforming using the determined direction vector. The method of claim 1, wherein the uplink or downlink beamforming is performed using the determined direction vector. 12. The method of claim 11, If it is determined in step (c) that the inner product value is not equal to or greater than the threshold value, Estimating a direction vector using a received signal during a predetermined number of direction vector determination periods while maintaining the beam direction by the second direction vector, and when the estimated direction vector corresponds to the first direction vector, And determining the one-direction vector to be a direction vector for beamforming. A base station transceiver having an array antenna is a method for forming an uplink or downlink beam, (a) estimating a first direction vector using a signal received through a plurality of antennas; (b) obtaining an inner product of the estimated first direction vector and a second direction vector determined in a previous direction vector determination period; (c) comparing the determined inner product value with a predetermined threshold value to determine whether the inner product value is greater than or equal to a threshold value; And (d) determining the first direction vector as a direction vector for beam forming if the inner product value is greater than or equal to a threshold value as a result of the determining in step (c) Wherein the base station transmitter and receiver includes an array antenna. 15. The method of claim 14, If it is determined in step (c) that the inner product value is not equal to or greater than the threshold value, Obtaining an inner product between the first direction vector and direction vectors for a previous predetermined period; And And determining a direction vector having a maximum value among the obtained inner product values as a direction vector for beamforming. 16. The method according to claim 14 or 15, And storing the determined direction vector for beamforming as a previous direction vector value. ≪ RTI ID = 0.0 > 8. < / RTI > 15. The method of claim 14, If it is determined in step (c) that the inner product value is not equal to or greater than the threshold value, Further comprising: multiplying the first direction vector and the second direction vector by weights, respectively, to obtain a third direction vector, and determining the third direction vector as a direction vector for beam formation A method of beam forming in a base station transceiver.

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