KR20170139882A - Beamforming Device and Method using phase shifter - Google Patents

Abstract

The present invention discloses a device and a method for forming a beam, which can maintain the quality of a service while increasing capacity and coverage of a system, and can reduce costs. To this end, the device for forming a beam comprises: a modulation/demodulation part converting and outputting transmission data into an RF signal; a divider dividing the RF signal into a plurality of signals including a first signal and a second signal; a phase shifter changing a phase of the second signal of the divider; and an antenna transmitting the first signal and the second signal in which the phase is changed. The phase shifter changes the phase of the second signal among a plurality of phases having the greatest intensity of a feedback signal.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0001] The present invention relates to a beam forming apparatus and method using a phase shift,

The present invention relates to a beam forming apparatus and method capable of increasing the capacity and coverage of a system by applying transmit diversity, maintaining quality of service, and reducing cost.

As the amount of data serviced in the mobile communication system rapidly increases and the number of users increases, more system capacity is required.

In addition, a mobile communication system typically has a configuration in which a plurality of UEs (User Equipments) communicate with each other through a single base station. In a high-speed data transmission, a fading phenomenon occurs on a radio channel, The transmission power of the mobile communication terminal is increased.

Diversity technology has recently come to the fore in order to meet such a demand and overcome the fading phenomenon.

Transmit diversity technology has been difficult to apply to mobile communication terminals due to limited conditions such as size of terminal, power consumption, and complexity of system. Recently, development of Half power PAM (PAM) It is possible to apply the transmit diversity technique to the mobile communication terminal by adding only one diversity chip. However, it is difficult to apply it because of the increase of the manufacturing cost by adding the space limitation of the mobile communication terminal and the high directivity of the chip.

The present invention provides a beam forming apparatus and method capable of increasing the capacity and coverage of a system, maintaining quality of service, and reducing cost.

A beam forming apparatus according to the present invention includes: a modulation and demodulation unit for converting transmission data into an RF signal and outputting the RF signal; A divider for dividing the RF signal into a plurality of signals including a first signal and a second signal; A phase shifter for changing the phase of the second signal of the divider; And an antenna for transmitting the first signal and the second signal whose phase is changed, and the phase shifter may change the phase of the second signal among a plurality of phases having the greatest intensity of the feedback signal.

Here, the phase shifter is divided into a plurality of phases by dividing the entire 360 ° phase at predetermined intervals, and the two phases having the greatest intensity can be derived by receiving the feedback signal for each phase.

The phase shifter can divide the entire 360 ° phase into 45 ° intervals.

Also, the phase shifter may be a 3-bit or 6-bit phase shifter.

The feedback signal may include a received signal strength indicator (RSSI) in the control chip, a value of a power control bit or a carrier power to noise power ratio (C / N) of a satellite, a dilution of Precision).

The phase shifter may change the phase of the second signal to an intermediate value between a plurality of phases having the greatest intensity of the feedback signal.

Also, the phase shifter may change the phase of the second signal to an intermediate value between two phases having the greatest intensity of the feedback signal.

In addition, the antenna may transmit the first signal and the phase-changed second signal in a radiation pattern, respectively.

According to another aspect of the present invention, there is provided a beam forming method including dividing a RF signal converted from transmission data by a divider into a plurality of signals including a first signal and a second signal; Shifting the phase of the phase shifter relative to the second signal; And an antenna transmitting the second signal; And the phase shifter may change the phase of the second signal to a value between a plurality of phases having the largest intensity among the feedback signals.

Here, the phase shifter is divided into a plurality of phases by dividing the entire 360 ° phase at predetermined intervals, and the two phases having the greatest intensity can be derived by receiving the feedback signal for each phase.

The phase shifter can divide the entire 360 ° phase into 45 ° intervals.

The feedback signal may include a received signal strength indicator (RSSI) in the control chip, a value of a power control bit or a carrier power to noise power ratio (C / N) of a satellite, a dilution of Precision).

Also, the phase shifter may change the phase of the second signal to an intermediate value between two phases having the greatest intensity of the feedback signal.

Since the beam forming apparatus and method according to the present invention can change the phase of the second signal and transmit it together with the first signal as described above, beamforming can be performed at the receiving side, Lt; / RTI > Also, since the terminal can remove the shadow area and obtain the diversity gain, the transmission power can be reduced and the battery use time can be increased. Also, in the position of each cell, the power level of the transmission band may be reduced and the noise of the adjacent channel may be reduced.

1 is a schematic block diagram of a beam forming apparatus according to an embodiment of the present invention.
2 is a flowchart illustrating a beam forming method according to an embodiment of the present invention.
FIG. 3 shows a phase change of a variable path in a beam forming apparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily carry out the present invention.

Hereinafter, a configuration of a beam forming apparatus according to an embodiment of the present invention will be described.

1 is a schematic block diagram of a beam forming apparatus according to an embodiment of the present invention.

1, a beam forming apparatus 10 according to an exemplary embodiment of the present invention includes a modulator 110, a transceiver 120, an amplifier 130, a divider 140, a phase shifter 150, a PAM 160, and 170, duplexers 180 and 190, filters 200 and 210, and antennas 220 and 230.

The modem 110 converts analog transmission data received from a controller (not shown) into an RF signal or converts an RF signal received from the antennas 220 and 230 into an analog signal.

The transceiver 120 serves as a terminal for transmitting an RF signal received from the modem 110 or for applying a received RF signal to the modem 110.

The amplifier 130 amplifies the RF signal of the modulator 110 applied to the transceiver 120. The amplifier 130 can obtain a gain of a size suitable for transmitting the RF signal.

The divider 140 divides the RF signal output from the amplifier 130 into at least two paths including a first signal and a second signal. In the beam forming apparatus 10 according to the embodiment of the present invention, the divider 140 is divided into two paths of a first transmission path and a second transmission path. Accordingly, the power of the RF signal can be reduced by half and distributed to each transmission path.

The phase shifter 150 changes the phase of the second signal received from the divider 140 through the second transmission path. The phase shifter 150 may be connected to the modulator / demodulator 110 through a general purpose input / output (GIPO) or a MIPI interface.

As will be described later, the phase shifter 150 changes the phase of the second signal based on the received RSSI, which is fed back, and the second signal is separated from the first signal having no phase change So that it can be transmitted. When the phase shifter 150 is a 3-bit phase shifter, the phases are shifted from 0 ° (360 °) to 315 ° at 45 ° intervals at the time of phase change at the phase shifter 150 And determines two phases with the highest two values through the received signal strength indicator (RSSI). If the phase shifter 150 is a 6-bit phase shifter, the phase shifter 150 may vary the phase by 5.6 °, so that the precision of the phase shifter is related to the number of bits of the phase shifter 150.

Also, the phase shifter 150 changes the phase of the RF signal to an intermediate value of the two phases. Therefore, it is possible to determine a phase suitable for the position of the user. In addition, if the user moves or the surrounding situation changes, the directional (phase) of the antenna must be changed. In this case, the phase shifter 150 increases or decreases the phase of the second transmission path, and controls the phase with reference to the received signal strength varying.

Accordingly, since the path for receiving the RF signal is separated at the receiving side, diversity can be realized, and the fading phenomenon can be corrected accordingly.

The PAMs 160 and 170 perform pulse amplitude modulation on the RF signal of the second transmission path whose phase is changed from the RF signal of the first transmission path. The modulated RF signals can reduce the error rate.

The duplexers 180 and 190 separate the RF signals from the reception frequency. Accordingly, when anti-bidirectional transmission and reception are performed using the antennas 220 and 230, it is possible to prevent confusion between transmission and reception signals.

The filters 200 and 210 may be coupled to the downstream ends of the duplexers 200 and 210. The RF signal can be filtered before transmission through the filters 200 and 210.

The antennas 220 and 230 transmit RF signals having passed through the filters 200 and 210. In addition, in the case of the antennas 220 and 230, signals can be transmitted and received in both directions.

Hereinafter, a beam forming method according to an embodiment of the present invention will be described.

2 is a flowchart illustrating a beam forming method according to an embodiment of the present invention. FIG. 3 shows a phase change of a variable path in a beam forming apparatus according to an embodiment of the present invention.

Referring to FIG. 2, a beam forming method according to an exemplary embodiment of the present invention includes a power dividing step S1, a phase shifting step S2, a signal transmitting step S3, a feedback signal comparing step S4, Step S5 may be included.

The power distribution step S1 is a step of dividing the power of an RF signal to be transmitted by the divider 140 into a plurality of power signals. In the beam forming method according to the embodiment of the present invention, the first signal and the second signal are divided into two parts. Also, a first one of the distributed RF signals is applied to the PAM 160 along the first transmission path, and the remaining second signal is applied to the phase shifter 150.

Referring to FIG. 2 and FIG. 3, the phase shifting step S2 is a step of changing the phase of the second signal applied to the phase shifter 150. FIG. The phase shifter 150 repeats the phase shifting step S2 and the feedback signal comparing step S4 in the same manner as in the phase shifting step S2 of FIG. 3 except that the phases are shifted from 0 ° (360 °) to 315 ° at intervals of 45 ° . Therefore, when the phase is changed at intervals of 45 degrees, the phase shifting step (S2) to the feedback signal comparing step (S4) may be repeated eight times.

The signal transmission step S3 is a step of transmitting the second signal having the displaced phase through the PAM 170, the duplexer 190, the filter 210 and the antenna 230. The second signal may be transmitted in a state in which the phase is sequentially displaced in accordance with the phase displacement step (S2) at intervals of a predetermined time.

The feedback signal comparison step S4 compares the received signal strength (RSSI) of the control chip with feedback in real time. However, it is also possible to use the value of the power control bit, the carrier power to noise power ratio (C / N) of the satellite, the DOP Dilution of Precision). Therefore, the two largest values can be found by comparing the RSSIs fed back. Also, the phase for the two values can be determined accordingly.

Referring to FIG. 3, the phase changing step S5 is a step of changing the phase of the RF signal to an intermediate value of the two phases in which the phase shifter 150 is determined. For example, as shown in FIG. 3, if there is the greatest received signal strength at 0 ° (360 °) and 315 °, respectively, the phase shifter 150 will determine the phase of the second signal Can be changed. Thus, it is possible to determine a phase suitable for the current position of the user.

Therefore, the beam forming apparatus and method according to the embodiment of the present invention can change the phase of the second signal and transmit it together with the first signal, as described above, to be beamformed at the receiving side The diversity implementation becomes possible. Also, since the terminal can remove the shadow area and obtain the diversity gain, the transmission power can be reduced and the battery use time can be increased. Also, in the position of each cell, the power level of the transmission band may be reduced and the noise of the adjacent channel may be reduced.

It is to be understood that the present invention is not limited to the above embodiment and that various modifications and changes may be made without departing from the scope of the present invention as set forth in the claims below, It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

10; Beam forming device 110; Modulator
120; A transceiver 130; amplifier
140; A divider 150; Phase shifter
160, 170; PAM 180, 190; Duplexer
200, 210; Filters 220 and 230; antenna

Claims (13)

A modulation and demodulation unit for converting transmission data into an RF signal and outputting the RF signal;
A divider for dividing the RF signal into a plurality of signals including a first signal and a second signal;
A phase shifter for changing the phase of the second signal of the divider; And
And an antenna for transmitting the first signal and the second signal whose phase is changed,
Wherein the phase shifter changes the phase of the second signal among a plurality of phases having the greatest intensity of the feedback signal. The method according to claim 1,
Wherein the phase shifter shifts a plurality of phases by dividing an entire 360 ° phase at predetermined intervals and receives the feedback signal for each phase to derive two phases having the largest intensity. 3. The method of claim 2,
Wherein the phase shifter divides the entire 360 phase into 45 DEG intervals. The method according to claim 1,
Wherein the phase shifter is a 3-bit or 6-bit phase shifter. The method according to claim 1,
The feedback signal may include a received signal strength indicator (RSSI) in the control chip, a value of a power control bit or a carrier power to noise ratio (C / N) of a satellite, a dilution of precision (DOP) ≪ / RTI > The method according to claim 1,
Wherein the phase shifter changes the phase of the second signal to an intermediate value between a plurality of phases having the greatest intensity of the feedback signal. The method according to claim 1,
Wherein the phase shifter changes the phase of the second signal to an intermediate value between two phases having the greatest intensity of the feedback signal. The method according to claim 1,
Wherein the antenna transmits the first signal and the phase-changed second signal in a radiation pattern, respectively. Dividing the RF signal converted from the transmission data by a divider into a plurality of signals including a first signal and a second signal;
Shifting the phase of the phase shifter relative to the second signal; And
The antenna transmitting the second signal;
Wherein the phase shifter changes the phase of the second signal to a value between a plurality of phases having the largest intensity among the feedback signals. 10. The method of claim 9,
Wherein the phase shifter is divided into a plurality of phases by dividing an entire 360 占 phase into a predetermined interval and receives the feedback signal for each phase to derive two phases having the largest intensity. 10. The method of claim 9,
Wherein the phase shifter divides the entire 360 phase into 45 DEG intervals. 10. The method of claim 9,
The feedback signal may include a received signal strength indicator (RSSI) in the control chip, a value of a power control bit or a carrier power to noise ratio (C / N) of a satellite, a dilution of precision (DOP) ≪ / RTI > 10. The method of claim 9,
Wherein the phase shifter changes the phase of the second signal to an intermediate value between two phases having the greatest intensity of the feedback signal.

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