KR20010067109A - High directivity coupler - Google Patents

Abstract

PURPOSE: A high directional coupler is provided to achieve a high directional coupler without a high-precision manufacturing process. CONSTITUTION: A directional coupler includes a transmission line(100), a first coupler(120) coupled to the transmission line(100), a second coupler(122) coupled to the transmission line(100), and a connector(124) having a first input connected to the first coupler and a second input connected to the second coupler. The first and second directional couplers which respectively generate a forward signal and a backward signal from a signal propagating through a transmission line. The connector connects the forward signals by an addition system and the backward signals so that they can cancel each other.

Description

High directivity coupler {HIGH DIRECTIVITY COUPLER}

The present invention relates to a directional coupler.

1 shows a conventional directional coupler. As shown, the directional coupler 20 is formed adjacent to the transmission line 10. Arrows along the transmission line 10 indicate the direction of transmission of the signal moving along the transmission line 10. The directional coupler 20 is connected to a signal to generate a traveling signal, and also to a partially reflected signal of the signal to generate an inverted signal. The inversion signal is passed through register 24 and then terminated. The directivity ratio of the directional coupler 20 is the forward signal power ratio when the signal moves in the transmission direction at the forward signal power ratio and the signal direction of the transmission line 10 is reversed. Thus, a 30 dB directional coupler with a 20 dB directivity ratio produces a progressive signal 30 dB down in the signal on the transmission line 10 and an inverted signal ˜50 dB down in the signal on the transmission line 10.

As shown in FIG. 1, conventional directional couplers have a directivity ratio from 15 dB to 30 dB. Through a high precision manufacturing process, the directivity ratio can be increased up to 45 dB. However, there is a need for a directional coupler with a high directivity ratio without the need for a high precision manufacturing process.

1 illustrates a prior art directional coupler.

2 illustrates a directional coupler in accordance with one embodiment of the present invention.

3 illustrates a directional coupler according to another embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

10: transmission line 20: directional coupler

24: Register 120: First Directional Coupler

122: second directional coupler 124: coupler

130: 0 degree combiner 132: working line

2 shows a directional coupler according to an embodiment of the invention. As shown, the first directional coupler 120 and the second directional coupler 122 are formed adjacent to the transmission line 100. However, in the difference in the manufacturing process, the first directional coupler 120 and the second directional coupler 122 are the same. Further, in the preferred embodiment, the first directional coupler 120 and the second directional coupler 122 have the same structure and operation as the directional coupler 20 of FIG.

An arrow along the transmission line 100 indicates the transmission direction of the main signal moving along the transmission line 100. The first directional coupler 120 and the second directional coupler 122 are arranged continuously along the transmission line 100, and by the first directional coupler 120 and the second directional coupler 122 that are out of phase of 270 degrees. It is separated by a predetermined distance such as the generated progress signal. That is, if the first traveling signal is generated by the first directional coupler 120 treated as having a reference phase of zero degrees, the second directional coupler is generated by the second directional coupler 122 having a phase of 270 degrees. Similarly, if the second inversion signal is generated by the second directional coupler 122 treated as having a reference phase of zero degrees, the first inversion signal is generated by the first directional coupler 120 having a phase of 270 degrees. .

The first directional coupler 120 and the second directional coupler 122 are connected to respective inputs of the 90 degree coupler 124. The combiner 124 has a combined progress signal output 126 and a terminated combined inverted signal output 128. In connection with the generation of the combined progress signal, the combiner 124 rotates the phase of the second progress signal by 90 degrees to combine the first progress signal and the second progress signal (hereinafter referred to as a 90 degree combiner). Similarly, combiner 124 rotates the phase of the second inversion signal by 90 degrees to combine the first and second inversion signals.

If the second traveling signal is rotated 90 degrees, the result of the phase for the first traveling signal is 270 degrees + 90 degrees = 360 degrees. As a result, the phase becomes the same when the first traveling signal and the second traveling signal are combined. Assuming that the first coupler 120 and the second coupler 122 are 30 dB couplers, and the coupler 124 is a 3 dB coupler with 20 dB cancellation, the combined traveling signal results in -27 dB relative to the main signal.

If the second inversion signal is rotated 90 degrees, the result of the phase is 0 degrees + 90 degrees = 90 degrees. As a result, the first and second travel signals are 180 degrees out of phase when combined (270 degrees and 90 degrees, respectively). Assuming that the first coupler 120 and the second coupler 122 are 30 dB couplers with a 20 dB directivity ratio, and the combiner 124 is a 3 dB coupler with 20 dB cancellation, the result of the combined inverted signal is relative to the main signal. -70dB. Therefore, the directivity ratio of the directional coupler is 43 dB.

3 shows another embodiment of a high directivity ratio coupler according to the present invention. The embodiment of FIG. 3 is identical to the embodiment of FIG. 2 except for the actuation line 132 disposed by the zero degree coupler 130 and disposed between the second directional coupler 122 and the zero degree coupler 130. . Unlike the 90 degree combiner 124, the zero degree combiner 130 has a phase of the second progress signal and the second inversion signal before combining the first progress signal and the first inversion signal with the second progress signal and the second inversion signal. Cannot rotate. In a preferred embodiment, the zero degree combiner 130 is a 3 dB Wilkenson coupler.

The actuation line 132 has a length through which the second traveling signal and the second inversion signal can be rotated 90 degrees before being provided to the zero degree coupler 130. As a result, zero degree combiner 130 and actuation line 132 are operated by means such as 90 degree combiner 124 to produce a combined traveling and inverted signal. Thus, the directional coupler according to the above and the preceding embodiments has a very high directivity ratio.

The present invention can be realized by those skilled in the art, and is not limited to the above-described embodiment. That is, the third directional coupler is continuously added to the first directional coupler 120 and the second directional coupler 122, and the three way coupler may be used instead of the two way coupler. Of course, the phase difference between the connected signals is adjusted (e.g., adjusting the spacing between the couplers), and the combiner is adapted to the appropriate phase-shift previously established or added for combining the forward signal and canceling the inverted signal. Have

Thus, as described above, it will be apparent that the present invention can be modified in many ways. Such changes and modifications are intended to be included within the scope of the appended claims without departing from the spirit and scope of the invention.

Claims (12)

Transmission line, A first coupler connected to the transmission line, A second coupler connected to the transmission line, And a coupler having a first input connected to the first coupler and a second input connected to a second coupler. The method of claim 1, And the coupler is a 90 degree coupler. And the coupler is a zero degree coupler. The method of claim 3, wherein And said zero degree coupler is a Wilkenson coupler. The method of claim 1, Wherein the first coupler and the second coupler are substantially the same coupler. The method of claim 1, Wherein the first coupler and the second coupler are 30 dB couplers. The method of claim 1, Wherein the first coupler and the second coupler couple a traveling signal in a transmission line such that the second coupler connects a signal that is 270 degrees out of phase from the first coupler. The method of claim 7, wherein And the coupler is a 90 degree coupler. The method of claim 7, wherein And the actuating line connects the coupler to the second coupler, the coupler being a zero degree coupler, such as a coupler for receiving a propagation signal connected by the first and second couplers of the same phase. The method of claim 1, The first coupler connects a first progress signal from a signal on a transmission line, The second coupler connects a second progress signal from a signal on a transmission line, and And the combiner couples the first progress signal and the second progress signal by additional means. The method of claim 10, The first coupler connects a first inversion signal, The second coupler connects a second inversion signal, And the coupler couples the first inversion signal and the second inversion signal to cancel the first inversion signal and the second inversion signal. The method of claim 1, And wherein the first coupler, the second coupler and the coupler are arranged as if the propagation signals from the coupled first coupler and the second coupler are combined in the same phase.