KR100676843B1 - Apparatus for time division dupexing switch - Google Patents

Abstract

A TDD(Time Division Depleting) switching apparatus is provided to enhance an IM(Inter Modulation) feature by arranging a hybrid coupler to use its feature such as reliability, thereby eliminating a switch disposed on a transmission line. A TDD switching apparatus comprises the first, second, and third circulators(610,620,630), an LNA(Low Noise Amplifier,670), and the first, second and third hybrid couplers(640,650,660). The first and second circulators(610,620) are arranged at an input stage connected with a BTS(Base station Transceiver System). The third circulator(630) is arranged at an output stage connected with an antenna. The LNA(670), arranged between the second and third circulators(620,630), performs low noise amplification on a signal transmitted from the third circulator(630). The first hybrid coupler(640), arranged on front ends of the first and second circulators(610,620), transfers a transmission signal from the BTS to the first and second circulators(610,620) and vice versa. The second hybrid coupler(650), arranged between the first and third circulators(610,630), transfers a signal from the first and second circulators(610,620) to the third circulator(630) and vice versa. The third hybrid coupler(660), arranged between the second circulator(620) and the LNA(670), transfers a signal from the LNA(670) to the first and second circulators(610,620).

Description

Time division duplex switching device {Apparatus for time division dupexing switch}

1 is an exemplary diagram for schematically illustrating a duplexer generally used in a base station;

2 is an exemplary diagram for schematically illustrating a conventional base station-based TDD switching device;

3 is a circuit diagram for actually implementing FIG.

4 is an exemplary diagram for schematically illustrating a conventional repeater-based TDD switching device;

5 is a circuit diagram for actually implementing FIG. 4;

6 is a structural diagram of a first embodiment of a TDD switching device according to the present invention;

7 is a structural diagram of a second embodiment of a TDD switching device according to the present invention;

8 is a structural diagram of a third embodiment of a TDD switching device according to the present invention;

<Description of Symbols for Main Parts of Drawings>

610 ~ 630, 710 ~ 740, 810 ~ 840: Circulator

640 ~ 660, 750 ~ 780, 850, 860: Hybrid Coupler

670, 790, 870, 880: LNA

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a time division duplex switching device, and more particularly, to time division duplex switching for transferring a signal between an antenna device and a base station transceiver system (hereinafter, simply referred to as a 'BTS') of a wireless communication system. Relates to a device.

In general, a scheme for transmitting and receiving signals between an antenna and a BTS includes frequency division duplexing (hereinafter, simply referred to as 'FDD') and time division duplexing (hereinafter, simply referred to as 'TDD'). There is this.

The FDD scheme uses different frequencies for transmission and reception, and the TDD scheme divides the same frequency in time, and uses the TDD scheme in WiBRO, which is a popular wireless wireless communication technology.

The switching device using such a TDD method separates transmission / reception signals by using switches in transmission (Tx) and reception (Rx) paths.

However, in the conventional method as described above, since switching is performed in a state in which a high output is transmitted at the time of transmission (Tx) signal, there is a problem in that the stability of the system is unreasonable, and inter-modulation (hereinafter, Simply called 'IM') is a problem that is degraded.

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above problems, and an object thereof is to provide a time division redundancy switching device for realizing system stability and improving IM characteristics by removing a switch in a transmission line.

In order to achieve the above object, according to a preferred embodiment of the present invention, a first circulator and a second circulator disposed at an input terminal connected to the base station converter (BTS); A third circulator disposed at an output terminal connected to the antenna; A low noise amplifier (LNA) disposed between second and third circulators and configured to perform low noise amplification on a signal received from the third circulator; Disposed in front of the first and second circulators, and transmits the transmission signals from the BTS to the first and second circulators, respectively, and transmits the signals from the first and second circulators to the BTS. A first hybrid coupler for; Disposed between the first and third circulators, transferring signals from the first and second circulators to the third circulator, and transmitting signals from the third circulator to the first and second circulators, respectively; A second hybrid coupler for delivery to the circulator; And a third hybrid coupler disposed between the second circulator and the LNA, the third hybrid coupler for transmitting signals from the LNA to the first and second circulators. .

In this case, the ports of the first hybrid coupler to which the transmission signal is input and the ports of the second hybrid coupler that transmits the signal to the third circulator are different in order, and the transmission signal input from the BTS is The first hybrid coupler-the first circulator-the second hybrid coupler-is transmitted to the antenna through a path connected to the second circulator.

In addition, a port of a third hybrid coupler to which a signal is input from the LNA and a port of the first hybrid coupler which transmits a signal to the BTS are different in order, and the received signal input through the antenna is the second signal. 3 Circulator-the LNA-the third hybrid coupler-the first circulator-the first hybrid coupler is routed through the path to the BTS.

In this case, it is preferable that the first and third circulators have a clockwise direction, and the second circulator has a counterclockwise direction.

On the other hand, according to another embodiment of the present invention, the first circulator and the second circulator disposed on the input terminal connected to the BTS; A third circulator and a fourth circulator disposed at an output terminal connected to the antenna; Disposed in front of the first and second circulators, and transmits the transmission signals from the BTS to the first and second circulators, respectively, and transmits the signals from the first and second circulators to the BTS. A first hybrid coupler for; It is disposed at the rear end of the third and fourth circulator, and transmits the received signal from the antenna to the third and fourth circulator, respectively, and transmits the signal from the third and fourth circulator to the antenna. A second hybrid coupler for; A third hybrid coupler for transmitting the received signals from the third and fourth circulators to an LNA; The LNA for performing low noise amplification of the received signal received from the third hybrid coupler; And a fourth hybrid coupler for transmitting the received signal received from the LNA to the first and second circulators.

In this case, the ports of the first hybrid coupler to which the transmission signal is input and the ports of the second hybrid coupler which transfers the transmission signal to the antenna are different in order, and the transmission signal input from the BTS is the same. A first path coupled to a first hybrid coupler, the first circulator, the third circulator, and the second hybrid coupler, and the first hybrid coupler, the second circulator, and the fourth circulator The ports of the second hybrid coupler which are transmitted to the antenna through the second path connected to the 2 hybrid couplers, and the ports of the third hybrid coupler which transmit the signals to the LNA are different in order. And a port of the fourth hybrid coupler to which a signal is input from the LNA and the first hybrid to transmit the received signal to the BTS. The ports of the coupler are different in order, and the ports of the third hybrid coupler that transmits signals to the LNA and the ports of the fourth hybrid coupler to which signals are input from the LNA are different in order, and thus, through the antenna. The received signal is input to the second hybrid coupler, the third circulator and the fourth circulator, the third hybrid coupler, the LNA, the fourth hybrid coupler, the first circulator and the second circulator. It is delivered to the BTS via a path to the first hybrid coupler.

In this case, it is preferable that the first and third circulators have a clockwise direction, and the second and fourth circulators have a counterclockwise direction.

Further, according to another embodiment of the present invention, the first circulator and the second circulator disposed on the input terminal connected to the BTS; A third circulator and a fourth circulator disposed at an output terminal connected to the antenna; Disposed in front of the first and second circulators, and transmits the transmission signals from the BTS to the first and second circulators, respectively, and transmits the signals from the first and second circulators to the BTS. A first hybrid coupler for; It is disposed at the rear end of the third and fourth circulator, and transmits the received signal from the antenna to the third and fourth circulator, respectively, and transmits the signal from the third and fourth circulator to the antenna. A second hybrid coupler for; A first LNA disposed between the first and third circulators and configured to perform low noise amplification on a signal received from the third circulator, and to transmit the low noise amplification to the first circulator; And a second LNA disposed between the second and fourth circulators and configured to perform low noise amplification on the signal received from the fourth circulator, and to transmit the low noise amplification to the second circulator. Is provided.

In this case, the ports of the first hybrid coupler for transmitting and receiving signals to and from the BTS and the ports of the second hybrid coupler for transmitting and receiving signals to and from the antenna are different in order, and the transmission signal inputted from the BTS is the first signal. A first path coupled to a hybrid coupler, the first circulator, the third circulator, and the second hybrid coupler, the first hybrid coupler, the second circulator, the fourth circulator, and the second path The received signal, which is transmitted to the antenna through a second path connected to the hybrid coupler, is input from the antenna to the second hybrid coupler, the third circulator, the first LNA, the first circulator, and the first. A first path connected to a hybrid coupler, the first hybrid coupler, the fourth circulator, the LNA, the second circulator, and the first hybrid Through the second path to the Doppler it is transmitted to the BTS.

In this case, it is preferable that the first and third circulators have a clockwise direction, and the second and fourth circulators have a counterclockwise direction.

Hereinafter, prior art will be described in more detail with respect to the prior art.

1 is an exemplary diagram schematically illustrating a duplexer generally used in a base station.

As shown in the figure, the general duplexer 120 is for separating a transmission signal and a reception signal, and a signal received from the antenna 110 is a low noise amplifier (hereinafter referred to simply as "LNA"). And transmits to the BTS through the divider 150 and transmits the received signal from the BTS 130 to a high power amplifier (hereinafter simply referred to as 'HPA') 130. It receives and separates it into a received signal and transmits the antenna 110 to radiate it.

Accordingly, the portion indicated by the dotted line in FIG. 1 is connected to the BTS and may also be referred to as a front end part or an antenna near product.

2 is an exemplary diagram for schematically illustrating a conventional base station-based TDD switching device.

As shown in the figure, it can be seen that the conventional base station-based TDD switching device is implemented using the switch 210.

3 is a circuit diagram for actually implementing FIG. 2.

As shown in the figure, a practically implemented TDD switching device uses a circulator 310 and a switch 320 disposed in a reception path.

The circulator 310 is a three-terminal signal branch circuit device, and the power incident to one port is output only to one of the other two ports, and the other device is a directional device.

Therefore, the signal transmitted through the transmission path is transmitted only to the antenna 110 by the circulator 310, and the signal received from the antenna 110 is only transmitted to the reception path by the circulator 310.

4 is an exemplary diagram for schematically illustrating a conventional repeater-based TDD switching device.

As shown in the figure, the conventional repeater-based TDD switching device, the transmission path and the reception path is not separated and use the same path, it is to be separated by the switch (420, 430).

FIG. 5 is a circuit diagram for actually implementing FIG. 4. As shown in the figure, in the conventional TDD switching apparatus of the relay method, when the transmission signal is transmitted from the BTS, the A switch 530 is turned off (OFF), when the reception signal is transmitted from the antenna 110 The A switch 530 operates to be ON.

However, in general, due to the isolation characteristics of the circulator, the received signal is input and transmitted to the transmission path, thereby degrading the voltage standing wave ratio (hereinafter, simply referred to as 'VSWR') characteristic of the antenna. There is a problem.

In order to solve this problem, a switch was placed in the path between the circulators to improve reflection characteristics. However, since the signal transmitted from the transmission path is a high output, this reduces the reliability of signal transmission and also causes an IM component. There was this.

Therefore, the present invention is to remove the switch used in the transmission path, to improve the reliability of signal transmission, and to eliminate the problems caused by the IM component.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same components have the same number as much as possible even if displayed on different drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

6 is a structural diagram of a first embodiment of a TDD switching device according to the present invention.

As shown in the figure, the TDD switching device of the present invention includes the first to third circulators 610, 620, 630, the first to third hybrid couplers 640, 650, and 660. And 670. LNA 670 is responsible for performing low noise amplification. Hereinafter, it is the same.

The first and third circulators 610 and 630 have a clockwise direction, and the second circulator 620 has a counterclockwise direction.

The first port of the first hybrid coupler 640 is grounded. In the following description of the present invention, for convenience, the port in the upper left part of the drawing of the hybrid coupler will be referred to as the first port, and the port in the lower left part will be referred to as the second port. In addition, the upper right port is called the second port, and the lower right port is called the fourth port. Referring to the second hybrid coupler of FIG. 6 as an example, the ports indicated by A to D become the first to fourth ports, respectively. In this case, it is assumed that the input at the first port is the first input and the output at the first port is the first output. However, this is for convenience of description of the present invention, and the present invention will not be limited thereto.

Referring to this, the fourth ports of the second hybrid coupler 650 and the third hybrid coupler 660 are grounded.

The first circulator 610 transfers the third output of the first hybrid coupler 640 to the first port of the second hybrid coupler 650, and transmits the first output of the third hybrid coupler 660. 1 is transmitted to the third port of the hybrid coupler 640. In addition, the first output of the second hybrid coupler 650 is transferred to the first port of the third hybrid coupler 660.

Hybrid couplers 640 to 660 are radio frequency (hereinafter referred to as 'RF') devices. The input signals are divided into two, so that the phase of each output signal has a 90 ° difference, and the amplitude of each is input. To ½ of the signal. When two such hybrid couplers are connected in series, the output signals of the ports in the same order as the ports of the input signals are finally canceled because their phases are reversed, and the signals of the other ports have the same phase and finally input signals. Is the same size as. That is, when a signal is input to the first port of the first hybrid coupler, no signal is output to the third port of the second hybrid coupler, and the same signal as the signal input to the first port is output to the fourth port. Since this is already well known in the RF field, a detailed description thereof will be omitted.

Accordingly, the transmission signal transmitted from the BTS through the first hybrid coupler 640 is transmitted to the antenna 110 through the paths of the first circulator 610, the second hybrid coupler 650, and the second circulator 620. Delivered and radiated.

Since the signal input from the BTS is changed through the two hybrid couplers 640 and 650, the order of the input port and the output port is different, it can be seen that the same signal as the input signal is radiated through the antenna 110.

In addition, the received signal input through the antenna 110 passes through the switch 680 and the LNA 670 of the reception path, and is input to the third hybrid coupler 660. The received signal is transmitted to the BTS through the paths of the first circulator 610 and the first hybrid coupler 640.

As the received signal is input, the order of the input port and the output port is changed through two hybrid couplers, so that the same signal as the input signal is transmitted to the BTS.

Meanwhile, among the signals input to the second hybrid coupler 650 due to the isolation characteristic of the second circulator 620, signals passing through the third circulator 630 and the third hybrid coupler 660 are 2. Since the order of the input port and the output port is the same through the two hybrid couplers, the signals are canceled from each other and the input signal is not radiated through the antenna 110 again, so that the VSWR characteristic of the antenna is excellent.

7 is a structural diagram of a second embodiment of a TDD switching device according to the present invention.

As shown in the drawings, the TDD switching device of the present invention includes the first to fourth circulators 710, 720, 730, and 740, and the first to fourth hybrid couplers 750, 760, 770, 780 and LNA 790. The first and third circulators 710 and 730 have clockwise directions, and the second and fourth circulators 720 and 740 have counterclockwise directions.

The transmission signal input through the first hybrid coupler 750 is connected to the first circulator 710, the third circulator 730, and the fourth hybrid coupler 780, and the second circulator 720. In addition, the radiation is transmitted to the antenna 110 through a path connected to the fourth circulator 740 and the fourth hybrid coupler 780.

In this case, the input signal is changed through the two hybrid couplers (750, 780), the order of the input port and the output port, it can be seen that the same signal as the input signal is radiated through the antenna.

In addition, the received signal input through the antenna passes through the fourth and third hybrid couplers 770 and 780 of the reception path, and is input to the second hybrid coupler 760 via the LNA 790. Thereafter, the signal passing through the first hybrid coupler 750 may be transmitted to the BTS. Since the received signal is input through the two hybrid couplers, respectively, the order of the input port and the output port is different in each case, it can be seen that the same signal as the input signal input to the antenna is transmitted to the BTS. That is, the ports of the fourth hybrid coupler 780 to which the received signal is input and the ports of the third hybrid coupler 770 which transmit signals to the LNA 790 are different in order, and from the LNA 790. Ports of the second hybrid coupler 760 to which a signal is input and ports of the first hybrid coupler 750 that transfer the received signal to the BTS are different in order, and the ports of the third hybrid coupler 770 are different. It can be seen that the ports and the ports of the second hybrid coupler 760 to which signals are input from the LNA 790 are different in order.

On the other hand, due to the isolation characteristics of the first circulator 710, the signal input to the fourth hybrid coupler 780 through the third circulator 730 is input through the two hybrid couplers 760 and 780. Since the order of the ports and the output ports is the same, they are canceled with each other so that the received signal is not radiated through the antenna 110 again, and due to the isolation characteristic of the second circulator 720, the fourth circulator Since the signals input to the fourth hybrid coupler 780 through the oscillator 740 are the same in the order of the input ports and the output ports through the two hybrid couplers 760 and 780, the received signals are canceled. It is not radiated again through the antenna 110.

8 is a structural diagram of a third embodiment of a TDD switching device according to the present invention.

As shown in the figure, the TDD switching device of the present invention includes the first to fourth circulators 810, 820, 830, and 840, the first and second hybrid couplers 850 and 860, and the first to fourth circulators. And first and second LNAs 870 and 880. The first and third circulators 810 and 830 have clockwise directions, and the second and fourth circulators 820 and 840 have counterclockwise directions.

The transmission signal input through the first hybrid coupler 850 is connected to the first circulator 810, the third circulator 830, and the second hybrid coupler 860, and the second circulator 820. The radiator is transmitted to the antenna 110 through a path connected to the fourth circulator 840 and the second hybrid coupler 860.

In this case, since the input signal is changed through the two hybrid couplers and the order of the input port and the output port, it can be seen that the same signal as the input signal is radiated through the antenna.

Meanwhile, the received signal input through the antenna is divided into two signals while passing through the second hybrid coupler 860.

First, the signal input to the third circulator 830 is output through the paths of the first LNA 870, the first circulator 810, and the first hybrid coupler 850, and the fourth circulator. The signal input to 840 is output through the paths of the second LNA 880, the second circulator 820, and the first hybrid coupler 850. At this time, the received signal input through the antenna, the order of the input port and the output port is changed through the two hybrid couplers, it can be seen that the same signal as the input signal is input to the BTS.

On the other hand, due to the isolation characteristic of the first circulator 810, the signal input to the second hybrid coupler 860 passes through two hybrid couplers 860 twice, and then the order of the input port and the output port. Are equal to each other, cancel each other, and the input signals are not radiated again through the antenna 110, and due to the isolation characteristic of the second circulator 820, the second hybrid coupler 860 Since the input signal is the same in the order of the input port and the output port through the two hybrid coupler (860 passes twice), and canceled each other, the input signal is not radiated again through the antenna 110.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes can be made in the art without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

The present invention as described above has the effect of enabling the elimination of a switch disposed on a transmission line by disposing a hybrid coupler and utilizing its characteristics, thereby improving the reliability of the TDD transmission line.

In addition, the present invention has the effect of improving the IM characteristics by arranging the hybrid coupler and utilizing its characteristics, thereby eliminating the switch disposed on the transmission line.

Claims (17)

A first circulator and a second circulator disposed at an input terminal connected to a base station converter (BTS); A third circulator disposed at an output terminal connected to the antenna; A low noise amplifier (LNA) disposed between second and third circulators and configured to perform low noise amplification on a signal received from the third circulator; Disposed in front of the first and second circulators, and transmits the transmission signals from the BTS to the first and second circulators, respectively, and transmits the signals from the first and second circulators to the BTS. A first hybrid coupler for; Disposed between the first and third circulators, transferring signals from the first and second circulators to the third circulator, and transmitting signals from the third circulator to the first and second circulators, respectively; A second hybrid coupler for delivery to the circulator; And And a third hybrid coupler disposed between said second circulator and said LNA, said third hybrid coupler for transferring signals from said LNA to said first and second circulators. The TDD switching device of claim 1, wherein a port of the first hybrid coupler to which the transmission signal is input and a port of the second hybrid coupler that transmits a signal to the third circulator are different in order. The transmission signal of claim 2, wherein the transmission signal input from the BTS is transmitted to the antenna through a path connected to the first hybrid coupler, the first circulator, the second hybrid coupler, and the second circulator. TDD switching device. The TDD switching device of claim 1, wherein a port of a third hybrid coupler to which a signal is input from the LNA and a port of the first hybrid coupler to transmit a signal to the BTS are different in order. The reception signal of claim 4, wherein the received signal input through the antenna is transmitted to the BTS through a path connected to the third circulator, the LNA, the third hybrid coupler, the first circulator, and the first hybrid coupler. TDD switching device. The TDD switching device according to any one of claims 1 to 5, wherein the first and third circulators have clockwise directionality, and the second circulator has counterclockwise directionality. A first circulator and a second circulator disposed at an input terminal connected to the BTS; A third circulator and a fourth circulator disposed at an output terminal connected to the antenna; Disposed in front of the first and second circulators, and transmits the transmission signals from the BTS to the first and second circulators, respectively, and transmits the signals from the first and second circulators to the BTS. A first hybrid coupler for; It is disposed at the rear end of the third and fourth circulator, and transmits the received signal from the antenna to the third and fourth circulator, respectively, and transmits the signal from the third and fourth circulator to the antenna. A second hybrid coupler for; A third hybrid coupler for transmitting the received signals from the third and fourth circulators to an LNA; The LNA for performing low noise amplification of the received signal received from the third hybrid coupler; And And a fourth hybrid coupler for transmitting the received signal received from the LNA to the first and second circulators. The TDD switching device according to claim 7, wherein a port of the first hybrid coupler to which the transmission signal is input and a port of the second hybrid coupler which transfers the transmission signal to the antenna are different in order. 10. The method of claim 8, wherein the transmission signal input from the BTS is a first path connected to the first hybrid coupler-the first circulator-the third circulator-the second hybrid coupler; And a second coupler connected to the hybrid coupler, the second circulator, the fourth circulator, and the second hybrid coupler. 8. The method of claim 7, wherein a port of a second hybrid coupler to which the received signal is input and a port of the third hybrid coupler to transmit a signal to the LNA are different in order, and the fourth to which a signal is input from the LNA. The ports of the hybrid coupler and the ports of the first hybrid coupler which transmits the received signal to the BTS are different in order, and a signal is input from the port of the third hybrid coupler that transmits the signal to the LNA and the LNA. And a port of the fourth hybrid coupler is different in order. The method of claim 10, wherein the received signal input through the antenna comprises: the second hybrid coupler-the third circulator and the fourth circulator-the third hybrid coupler-the LNA-the fourth hybrid coupler-the And a second circulator connected to a first circulator and a second circulator to a first hybrid coupler. 12. The TDD switching device according to any one of claims 7 to 11, wherein the first and third circulators have clockwise directionality, and the second and fourth circulators have counterclockwise directionality. A first circulator and a second circulator disposed at an input terminal connected to the BTS; A third circulator and a fourth circulator disposed at an output terminal connected to the antenna; Disposed in front of the first and second circulators, and transmits the transmission signals from the BTS to the first and second circulators, respectively, and transmits the signals from the first and second circulators to the BTS. A first hybrid coupler for; It is disposed at the rear end of the third and fourth circulator, and transmits the received signal from the antenna to the third and fourth circulator, respectively, and transmits the signal from the third and fourth circulator to the antenna. A second hybrid coupler for; A first LNA disposed between the first and third circulators and configured to perform low noise amplification on a signal received from the third circulator, and to transmit the low noise amplification to the first circulator; And A second LNA disposed between the second and fourth circulators and configured to perform low noise amplification on the signal received from the fourth circulator, and to transmit the low noise amplification to the second circulator. The TDD switching apparatus of claim 13, wherein a port of a first hybrid coupler that transmits and receives a signal to and from the BTS and a port of the second hybrid coupler that transmits and receives a signal to and from the antenna are different in order. The method of claim 14, wherein the transmission signal input from the BTS includes: a first path connected to the first hybrid coupler, the first circulator, the third circulator, and the second hybrid coupler; And a second coupler connected to the hybrid coupler, the second circulator, the fourth circulator, and the second hybrid coupler. The method of claim 14, wherein the received signal from the antenna is coupled to a first path connected to the second hybrid coupler, the third circulator, the first LNA, the first circulator, and the first hybrid coupler. And a first path coupled to the BTS through a second path connected to the first hybrid coupler, the fourth circulator, the LNA, the second circulator, and the first hybrid coupler. The TDD switching device according to any one of claims 13 to 16, wherein the first and third circulators have clockwise directionality, and the second and fourth circulators have counterclockwise directionality.

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