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A closed-loop transmitting antenna diversity method, and a base station and mobile station apparatus therefore in a next generation mobile telecommunications system, the closed-loop transmitting antenna diversity method having a plurality of antennas in a mobile telecommunications system, including

A closed-loop transmitting antenna diversity method, and a base station and mobile station apparatus therefore in a next generation mobile telecommunications system, the closed-loop transmitting antenna diversity method having a plurality of antennas in a mobile telecommunications system, including the steps of (a) measuring the changed amount per unit time of the phase difference between antennas for each of the plurality of antennas which are used in a base station; (b) transmitting the result of measuring as feedback information for adjusting transmitting antenna diversity; (c) receiving and interpreting feedback information in the base station; (d) calculating the weighted value of array antennas for each antenna, using the interpreted feedback information; and (e) multiplying data which is to be transmitted from the base station to a mobile station by the array antenna weighted value, and outputting the result through a corresponding antenna. Here, the changed amount per unit time of the phase difference between antennas is obtained by subtracting the previous phase difference between antennas which the base station knows from the phase difference between antennas which is calculated by a current mobile station.

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1. A closed-loop transmitting antenna diversity method having a plurality of antennas in a mobile telecommunications system, the closed-loop transmitting antenna diversity method comprising the steps of:(a) measuring, in a mobile station, the changed amount per unit time of the phase difference betw

1. A closed-loop transmitting antenna diversity method having a plurality of antennas in a mobile telecommunications system, the closed-loop transmitting antenna diversity method comprising the steps of:(a) measuring, in a mobile station, the changed amount per unit time of the phase difference between antennas for each of the plurality of antennas which are used in a base station; (b) transmitting the results of the measuring performed in step (a) as feedback information for adjusting transmitting antenna diversity to the base station; (c) receiving and interpreting feedback information in the base station; (d) calculating the weighted value of array antennas for each antenna, using the interpreted feedback information; and (e) multiplying data, which is to be transmitted from the base station to a mobile station, by the array antenna weighted value, and outputting the result through a corresponding antenna, wherein the changed amount per unit time of the phase difference between antennas is obtained by subtracting the previous phase difference between antennas, which the base station knows, from the phase difference between antennas, which is calculated by a current mobile station. 2. The closed-loop transmitting antenna diversity method as described in claim 1, wherein in step (a), the changed amount per unit time of the phase difference between antennas is measured using a downlink pilot signal, which is divided for respective mobile station users.3. The closed-loop transmitting antenna diversity method as described in claim 2, wherein, when a multipath channel is used, the changed amounts per unit time of each channel are added to each other using an eigen method in the step (a).4. The closed-loop transmitting antenna diversity method as described in claim 1, wherein, in step (d), the Doppler frequency of a signal received from each antenna is measured; results of the measuring are applied to the interpreted feedback information; and the array antenna weighted value of each antenna is obtained.5. A closed-loop transmitting antenna diversity method when two antennas are used in a mobile telecommunications system, the closed-loop transmitting antenna diversity method comprising the steps of:(a) obtaining, in a mobile station, the sign of the changed amount per unit time of the phase difference between antennas for the two antennas used in a base station; (b) transmitting the sign obtained in step (a) as feedback information for adjusting transmitting antenna diversity; (c) receiving and interpreting feedback information in the base station; (d) calculating the weighted value of array antennas for each antenna, using the interpreted feedback information; and (e) multiplying data, which is to be transmitted from the base station to a mobile station, by the array antenna weighted value, and outputting the result through a corresponding antenna, wherein the changed amount per unit time of the phase difference between antennas is obtained by subtracting the previous phase difference between antennas, which the base station knows, from the phase difference between antennas, which is calculated by a current mobile station. 6. The closed-loop transmitting antenna diversity method as described in claim 5, wherein the step (a) further comprises the sub-steps of:(1) conjugating a value obtained by measuring the channel of a base antenna among the two antennas, and multiplying the conjugated value by a pilot symbol, which is received by the base antenna; (2) selecting the imaginary part of the complex number result of the multiplication; and (3) determining the sign of the selected imaginary part and then, outputting a signal which indicates a positive value or a negative value. 7. The closed-loop transmitting antenna diversity method as described in claim 5, wherein the step (a), which is a multipath channel, further comprises the sub-steps:(1) conjugating all values obtained by measuring from a first multipath channel to an L-th multipath channel (wherein L is an integer greater than 1) of the base antenna among the two antennas, respectively, and multiplying each conjugated value by a corresponding multipath pilot symbol among a first multipath pilot symbol to an L-th multipath pilot symbol from the base station; (2) adding the results of the multiplication, and selecting the imaginary part of the complex number result of the multiplication; and (3) determining the sign of the selected imaginary part and then, outputting a signal which indicates a positive value or a negative value. 8. The closed-loop transmitting antenna diversity method as described in claim 5, wherein the step (d) further comprises the sub-steps of:(1) obtaining the optimum step size, by measuring a Doppler frequency in a signal received by the two antennas; (2) multiplying the interpreted feedback information by the step size; (3) obtaining the current phase difference between antennas by adding the result of the multiplication to the previous phase difference between antennas which the base station knows; and (4) calculating the weighted value of the array antennas for compensating the antenna phase, from the current phase difference between antennas. 9. The closed-loop transmitting antenna diversity method as described in claim 8, wherein, when it is not easy to measure a Doppler frequency in the sub-step 1 of step (d),the step size is set to π/4 by default, and the step size can switch from π/4 to π/2, or π/2 to π/4 in accordance with speed changes. 10. A closed-loop transmitting antenna diversity method when a plurality of antennas are used in a wireless telecommunications system, the closed-loop transmitting antenna diversity method comprising the steps of:(a) measuring, in a receiving station, the changed amount per unit time of the phase difference between antennas for a plurality of antennas used in a transmitting station; (b) transmitting to the transmitting station the results of measuring in step (a) as feedback information for adjusting transmitting antenna diversity; (c) receiving and interpreting in the transmitting station feedback information; (d) calculating the weighted value of array antennas for each antenna, using the interpreted feedback information; and (e) multiplying data, which is to be transmitted from the transmitting station to the receiving station, by the array antenna weighted value, and outputting the result through a corresponding antenna, wherein the changed amount per unit time of the phase difference between antennas is obtained by subtracting the previous phase difference between antennas, which the transmitting station knows, from the phase difference between antennas, which is calculated by a current receiving station. 11. A base station apparatus for implementing closed-loop transmitting antenna diversity, when two antennas are used in a mobile telecommunications system, the base station comprising:first and second antennas, one or both of which receives feedback information generated from any i-th mobile station; a feedback information decoder for interpreting the received feedback information and detecting the changed amount per unit time of the phase difference between antennas; a weighted value calculating unit for calculating the weighted value of the second antenna, using the changed amount per unit time; and a transmitting unit for transmitting a data signal and a pilot signal to the mobile station through the first antenna, and transmitting the result of multiplication through the second antenna, after multiplying the data signal by the array antenna weighted value, wherein the changed amount per unit time of the phase difference between antennas is a value obtained by adding the changed amount per unit time of the phase difference between antennas, which is measured as feedback information in the mobile station, to a feedback error due to uplink channel noise. 12. The base station apparatus of claim 11, wherein the weighted value calculating unit further comprises:a Doppler measuring unit for measuring a Doppler frequency in a signal received by the first antenna and a second antenna, and calculating the optimum step size in proportion to the result of measuring; a first multiplier for multiplying the changed amount per unit time of the phase difference between antennas detected in the feedback decoder by the step size; a delay unit for storing the phase difference between antennas, which is delayed for a predetermined time; an adder for outputting the phase difference between antennas by adding the output of the first multiplier and the output of the delay unit; and a phase adjusting unit for outputting a phase compensating value, which corresponds to the phase difference between antennas, as the weighted value of the second antenna. 13. The base station apparatus of claim 12, wherein the Doppler measuring unit determines the step size to be π/4 by default when it is not easy to measure a Doppler frequency, and includes a switch for switching the step size from π/4 to π/2, or π/2 to π/4 in accordance with speed changes.14. A mobile station apparatus for implementing closed-loop transmitting antenna diversity when two antennas are used in a base station, the mobile station apparatus comprising:a plurality of fingers 1 through L for conjugating each of L multipath channels, from a first multipath channel through an L-th multipath channel, of a base antenna among two antennas, and receiving each multipath pilot symbol, from a first multipath pilot symbol to an L-th multipath pilot symbol, from the base antenna; a plurality of multipliers from 1 through L for multiplying the conjugated value by each corresponding pilot symbol; an adder for adding the outputs of the plurality of multipliers 1 through L; an imaginary number selecting unit for selecting the imaginary part of a complex number signal which is the output from the adder; and a determining unit for determining the sign of the selected imaginary part, and outputting a signal indicating a positive value or a negative value as feedback information. 15. The mobile station apparatus of claim 14, wherein the feedback information is delivered to the base station.16. The mobile station apparatus of claim 14, wherein the feedback information is for adjusting transmitting antenna diversity.17. The mobile station apparatus of claim 14, wherein the feedback information includes a sign of a changed amount per unit time of a phase difference between the two antennas in the base station.