KR19990033683U - Connecting member for extending antenna band width - Google Patents

Abstract

The present invention does not modify the characteristics of the existing antenna at all, and forms a flat portion in the impedance transformer, which is the feeder to which the antenna is connected, thereby converting the parallel resonance, which is a general characteristic of the antenna, into a series resonance, thereby widening the bandwidth of the narrow antenna. The band width can be expanded and adjusted according to the size, height and width of the plane of the impedance transformer, and the number of antennas wound on the impedance transformer, and various frequencies can be satisfied so that the center frequency can be moved immediately due to various environments of the antenna. There is this.

Description

CONNECTING MEMBER FOR EXTENDING ANTENNA BAND WIDTH to widen the bandwidth of the antenna

The present invention relates to a connecting member for widening the bandwidth of an antenna. More specifically, the width of the antenna is increased and increased according to the impedance transformer having a predetermined plane, the length of the antenna installed thereon, and the number of turns of the impedance transformer. The present invention relates to a connecting member for widening the bandwidth of an antenna so as to easily adjust the bandwidth.

The general feeding structure of the small antenna used in the conventional wireless communication is a form of feeding the coaxial line directly. In the case of the monopole, the + part is fed to the coaxial line, and in the case of the dipole, the +, The part is fed to the antenna.

This method causes an unbalance between the feed lines of the antennas, which makes it difficult to actually match the impedances of the antennas. In addition, since the contact point between the antenna and the feed line is changed from time to time, the characteristics of the manufactured antenna are not constant and the efficiency of the antenna is considerably reduced.

In addition, US Patent No. 4,772,895 is proposed as shown in the accompanying drawings to improve the shortcomings in the coaxial line, which relates to an antenna for widening the frequency response, the structure includes a signal feed portion and a ground portion A first conductive element 200 having a feed port and having opposite opposite ends and having a first pitch and a first electrical length, wherein one end of the first element is a signal feed part of the feed port 500; And a second spirally conductive element 400 coupled to and having opposing opposite ends, the second element having a second pitch and a second electrical length, the second element being wound coaxially around a portion of the first element. One end of the second device 400 is coupled to the ground of the feed port, wherein the second pitch is approximately one half of the first pitch and the second electrical length is approximately one third of the first electrical length. 1 element And a cylindrical spacer means 300 disposed coaxially between the first element and the second element to electrically insulate the 200 and the second element 400, wherein the spacer means comprises a first element and a second element. The antenna is characterized in that it is thin enough to be firmly coupled to the antenna to increase the frequency response represented by the first element, which means that the structure of the connecting member between the antenna and the coaxial line is improved, but the unbalanced condition that is actually a problem in general antennas is improved. There is a problem in that the efficiency of the antenna is reduced and the size is not improved because it is not improved.

The present invention was devised to solve the above problems, and the parallel resonance, which is a general characteristic of the antenna, is converted into series resonance by forming a flat portion at an impedance transformer, which is a feeder, on which an antenna is installed, without modifying the characteristics of the existing antenna. A connection member that widens the bandwidth of the antenna to widen the bandwidth of the antenna by widening the band width by the size, height and width of the impedance transformer, and the number of windings wound on the impedance transformer. To provide.

Another object is to provide a connection member that can satisfy various frequencies, so that it can immediately cope with the movement of the center frequency due to various environments of the antenna.

The object of the present invention is to connect to the antenna resonating at the center frequency of the transmission and reception frequency band and the connector of the wireless communication device to feed the antenna through an impedance transformer which is a feeding part, so as to coincide with the vertical axis of the impedance transformer A connecting member for widening a band width of the antenna, wherein the antenna has a cut surface; A connection member for widening a band width of an antenna, wherein a groove is vertically formed in the cut plane of the impedance transformer; A connection member for widening the band width of the antenna, wherein the impedance transformer forms a cylindrical shape and a plurality of semicircular grooves are formed at predetermined intervals under one side of the outer circumference; A connection member for widening the bandwidth of the antenna whose bandwidth is adjusted according to the height of the antenna installed in the impedance transformer; A connecting member for widening the band width of the antenna, wherein the band width of the antenna is adjusted by the cut area of the impedance transformer having the plane cut off; A connection member for maintaining the bandwidth of the antenna as the cylindrical diameter of the impedance transformer increases or decreases, but widens the bandwidth of the antenna in which a resonance frequency flows; The impedance transformer is achieved by a connecting member for widening the band width of the antenna, characterized in that installed at least two on the vertical center line when the antenna is extended or folded.

1 is a perspective view showing the structure of the connection member of the present invention.

Figure 2a to 2b is a perspective view showing an embodiment of the connection member of the present invention.

Figure 3a is a characteristic diagram that the center frequency of the antenna using the connection member of the present invention measured by the return loss value 315MKz, Figure 3b is the return loss when the center frequency of the antenna using the connection member of the present invention is 850MKz (Retracted) A graph of values.

4 is a front view showing a conventional antenna structure.

FIG. 5A is a characteristic diagram of an antenna using a conventional connecting member measured by a return loss value, and FIG. 5B is a graph showing a return loss value of an antenna using a conventional connecting member.

※ Explanation of code for main part of drawing ※

10: connecting member 11: impedance transformer

11a: flat part 11b: groove

12: engaging jaw 13: fastening portion

14: groove

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 2 is a perspective view showing a connection member of the present invention, and according to this, a fastening part 13 fastened to a connector 12 for supporting an antenna resonating at a center frequency of a transmission / reception frequency band and a connector of a wireless communication device, not shown. In the connecting member consisting of the impedance transformer 11 of the cylindrical shape to feed power)

The structure of the connecting member 10 of the present invention is a structure in which the flat portion 11a is formed by cutting or paralleling the parallel center lines of the antennas installed in the cylindrical impedance transformer 11.

In addition, Figure 2a is a perspective view showing another embodiment of the present invention to form a groove (11b) in the longitudinal direction in the inner flat portion (11a) of the impedance transformer 11, which is a feed portion, the groove (11b) is caught It is a structure configured to coincide with the center hole communicating the frame 12 and the fastening portion 13.

In addition, Figure 2b is a perspective view showing another embodiment of the present invention a plurality of grooves 14 at a predetermined interval on the lower side of one side of the outer periphery of the cylindrical impedance transformer of the connecting member 10 for feeding and feeding the antenna. Although the dogs are formed, the recess 14 has a semicircular shape.

Referring to the effect of the connection member 10 to widen the bandwidth of the present invention having the structure as described above, when the antenna resonating at the center frequency of the transmission and reception band around the impedance transformer 11 is wound and grounded, this feed As the negative impedance transformer 11 modulates the parallel resonance, which is a general characteristic, into a series resonance, its bandwidth is widened at the actual center frequency.

In fact, the results of the structure will be described as follows. When the resonant circuit of the antenna generally causes parallel resonance, the Q value (goodness of the lossy reactance element or the resonant circuit) becomes considerably large, resulting in a considerably smaller bandwidth.

However, it can be seen that the desired bandwidth can be obtained in a wide frequency band if the input member structure of the present invention is converted into a distributed constant circuit and the input impedance viewed from the feed point causes series resonance.

In this experiment, the helical antenna for the NORMAL mode was tested and the accompanying drawings. FIG. 5A is a conventional antenna characteristic measured by a return loss value. The feed structure uses an I-shaped fastening structure, and the size (diameter) is 3 mm. As a result of using a cylindrical impedance transformer with a height of 10mm as a contact, it can be seen that the -20dB bandwidth is about 8MHz.

Also. Figure 3a is a characteristic diagram of the center frequency of the antenna using the connection member 10 of the present invention measured by the return loss value of 315MKz in order to expand the bandwidth (diameter) of 3mm in diameter and 10mm in height The center of the impedance transformer was cut off to form a plane. As a result, the -20dB bandwidth was about 20MHz.

Comparing FIG. 5A and FIG. 3A, the frequency used here is 315MKz, and the bandwidth of the antenna is increased about 2.5 times with respect to the center frequency at the return loss of -20dB. It can be seen that it can be applied to various linear antennas and micro strip antennas as well as helical antennas.

On the other hand, Figure 3b is a return loss that cut the center of the cylindrical impedance transformer 11 having a size (diameter) of 5mm and a height of 2mm of the connection member 10 of the present invention to form a flat portion (11a) (Retracted) shows the graph of VSWR (Voltage Standing Wave RATIO) and impedance data. It can be seen that the frequency width is 750-950MKz, the center frequency is 850MKz, and the bandwidth is wider than the conventional antenna of FIG. 5B. have.

In addition, when changing the conditions of the impedance transformer 11 and the antenna fixedly installed to each other look at the change of the bandwidth,

First, the size (length) of the antenna and the size (diameter) of the impedance transformer 11 are the same, and when the height of the impedance transformer is changed, the change of the bandwidth is narrowed and the resonance frequency moves to a low frequency.

In addition, when the size (length) of the antenna and the height of the impedance transformer 11 are the same and the size (diameter) of the impedance transformer is changed, that is, when the diameter is increased, the bandwidth is maintained but the resonance frequency is moved to a low frequency, and the antenna beam is directed upward. As the diameter decreases, the band width is maintained, but the change of the width narrows and the resonance frequency moves to a low frequency.

In the connection member having the same size (diameter) and height of the impedance transformer 11, the cutting member is cut to be equal to the vertical center line. When the cutting area is changed, the band width of the VSWR increases as the cutting area is changed. The resonant frequency is reduced and the resonant frequency becomes constant. As the cut area decreases, the bandwidth of the VSWR increases, but the resonant frequency moves to the high frequency band.

On the other hand, when the number of turns to be fixed to the impedance transformer 11 having the same size (diameter) and height is changed, the antenna length is actually shortened, so the resonance frequency moves to a high frequency and the bandwidth is also reduced.

On the other hand, in the structure of another embodiment of the present invention as shown in Figure 2a attached to the resonant frequency center band in the transmission and reception frequency band on the outer periphery of the impedance transformer 11 is formed a long groove (11b) that can not change the resonance characteristics of the general antenna The bandwidth of the antenna is widened due to a change in the resonance characteristic caused by the structure of the connecting member that feeds the antenna through the impedance transformer.

On the other hand, in the structure of another embodiment of the present invention as shown in Figure 2b of the accompanying drawings, the connecting member 10 for feeding and feeding the antenna to an impedance transformer having a plurality of grooves 14 formed on the outer periphery of the impedance transformer 11, which is a feeder. Since the structure of resonates in the resonance characteristics, the desired bandwidth can be obtained.

On the other hand, the connection member of the present invention is provided with the impedance transformer alone on the vertical center line of the antenna separately from the connection member 10 of the structure in which the impedance transformer 11 is formed integrally at a predetermined interval, between which a conventional antenna It may be used to have a structure that is provided, it may be formed in the plane corresponding to each other the planar portion (11a) provided in the impedance transformer (11).

Therefore, the present invention converts the resonance circuit of the antenna from parallel resonance to series resonance by modifying the shape of the impedance transformer formed on the connecting member, so that any antenna that generally causes parallel resonance at the center frequency is 2-3 times higher than the conventional one. The above bandwidth can be obtained and the bandwidth can be adjusted as necessary.

The present invention as described above extends to form the necessary bandwidth by adjusting the bandwidth by compensating parallel resonance, which is a general characteristic of the antenna, with serial resonance without changing the original shape of the existing antenna at all. Regardless of the type, the band width can be extended according to the fastening structure.

In addition, the size and height of the impedance transformer, that is, the width of the antenna is widened by the deformation of the structure and the number of turns of the antenna fixed thereto. It is effective to cope with the movement immediately.

Claims (8)

In the connecting member that is connected to the antenna resonating at the center frequency of the transmission and reception frequency band and the connector of the wireless communication device to feed the antenna through an impedance transformer which is a feeder Connection member for widening the band width of the antenna, characterized in that the cut to form a plane by cutting parallel to the vertical axis of the impedance transformer. The connecting member of claim 1, wherein a groove is vertically formed in the cut plane of the impedance transformer. 2. The connecting member of claim 1, wherein the impedance transformer has a cylindrical shape and a plurality of semicircular grooves are formed at one side of the outer circumference at predetermined intervals. The connecting member according to claim 1, wherein the band width of the antenna is widened according to the height of the antenna installed in the impedance transformer. 2. The connecting member according to claim 1, wherein the antenna bandwidth is adjusted as the cut area of the impedance transformer having the plane cut off becomes larger or smaller. The connecting member according to claim 1, wherein the bandwidth of the antenna is maintained as the cylindrical diameter of the impedance transformer increases or decreases, but the bandwidth of the antenna in which the resonance frequency flows is increased. 2. The connecting member of claim 1, wherein the impedance transformer is provided in two or more on the vertical center line when the impedance transformer is extended or folded. The connecting member of claim 1, wherein the plane of the impedance transformer is formed of two or more planes corresponding to each other.