CN111489863B - Coaxial line structure - Google Patents
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- CN111489863B CN111489863B CN202010371876.2A CN202010371876A CN111489863B CN 111489863 B CN111489863 B CN 111489863B CN 202010371876 A CN202010371876 A CN 202010371876A CN 111489863 B CN111489863 B CN 111489863B
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- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
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Abstract
The invention discloses a coaxial line structure, which comprises: a plurality of first sub-lines and a plurality of second sub-lines, the first sub-lines having a first characteristic impedance, the plurality of second sub-lines and the plurality of first sub-lines being spaced apart from each other and being periodically connected, the second sub-lines including: a plurality of first sub-lines connected in parallel with each other such that the second sub-line has a second characteristic impedance. According to the invention, the second sub-line comprises a plurality of first sub-lines which are mutually connected in parallel, so that the coaxial line structure with the electromagnetic band gap characteristic is formed by using the coaxial line with the same characteristic impedance, the manufacturing cost is lower, and the difficulty and the complexity of circuit realization are greatly reduced. In addition, the invention also unexpectedly realizes a coaxial line structure which can improve the characteristic impedance ratio of the coaxial line, and realizes the phenomena of faster super light speed and slower slow light speed.
Description
Technical Field
The invention relates to the field of electricity, in particular to an impedance coaxial line structure capable of generating electromagnetic band gap characteristics.
Background
The present coaxial line structure generating electromagnetic band gap characteristic is formed by alternately connecting two coaxial lines with different characteristic impedances, and belongs to a periodic impedance coaxial line structure. In other words, the coaxial line structure in the prior art needs to use two different characteristic impedances to realize the coaxial line with the electromagnetic band gap characteristic, which increases the difficulty in realizing the coaxial line structure and the manufacturing cost.
Disclosure of Invention
Technical problem to be solved
The invention discloses a coaxial line structure, aiming at solving the technical problems that the structure is difficult to realize and the manufacturing cost is high because a coaxial line structure with electromagnetic band gap characteristics needs to use two coaxial lines with different characteristic impedances in the prior art.
(II) technical scheme
The invention discloses a coaxial line structure, wherein the coaxial line structure comprises: a plurality of first sub-lines and a plurality of second sub-lines, each first sub-line having a first characteristic impedance, the plurality of second sub-lines and the plurality of first sub-lines being spaced apart from each other and being periodically connected, the second sub-lines including: a plurality of first sub-lines connected in parallel with each other such that the second sub-line has a second characteristic impedance.
According to an embodiment of the invention, wherein the first sub-line has x and the second sub-line has y, wherein x and y satisfy: x is y, x is y-1, or y is x-1, and x and y are positive integers.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: a third sub-line, the third sub-line comprising: a plurality of first sub-lines connected in series with each other such that a third sub-line has a third characteristic impedance.
According to the embodiment of the invention, the third sub-line is located at the first position, the second position or the third position of the coaxial line structure, the first position enables one end of the third sub-line to be connected with the first sub-line, the other end of the third sub-line to be connected with the second sub-line, the second position enables one end of the third sub-line to be connected with the first sub-line or the second sub-line, and the other end of the third sub-line is an external connection end of the coaxial line structure; the third position enables one end of the third sub-line to be connected with the first sub-line, and the other end of the third sub-line to be connected with the other first sub-line; or one end of the third sub-line is connected with the second sub-line, and the other end of the third sub-line is connected with the other second sub-line.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: a fourth sub-line, the fourth sub-line comprising: a plurality of second sub-lines connected in series with each other such that a fourth sub-line has a fourth characteristic impedance; and any two of the first sub-line, the second sub-line, the third sub-line and the fourth sub-line are connected.
According to the embodiment of the invention, the fourth sub-line is located at the first position, the second position or the third position of the coaxial line structure, the first position enables one end of the fourth sub-line to be connected with the first sub-line, the other end of the fourth sub-line to be connected with the second sub-line, the second position enables one end of the fourth sub-line to be connected with the first sub-line or the second sub-line, and the other end of the fourth sub-line is an external connection end of the coaxial line structure; the third position enables one end of the fourth sub-line to be connected with the first sub-line, and the other end of the fourth sub-line to be connected with the other first sub-line; or one end of the fourth sub-line is connected with the second sub-line, and the other end of the fourth sub-line is connected with the other second sub-line.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: a connection structure for connection between the first sub-line and the second sub-line.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: and the connecting structure is used for connecting any two of the first sub-line, the second sub-line and the third sub-line.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: and the connecting structure is used for connecting any two of the first sub-line, the second sub-line, the third sub-line and the fourth sub-line.
According to an embodiment of the present invention, wherein the connection structure is a joint or a microwave power divider, the joint includes: three-way joint, four-way joint, six-way joint.
(III) advantageous effects
The invention discloses a coaxial line structure, which comprises: a plurality of first sub-lines and a plurality of second sub-lines, the first sub-lines having a first characteristic impedance, the plurality of second sub-lines and the plurality of first sub-lines being spaced apart from each other and being periodically connected, the second sub-lines including: a plurality of first sub-lines connected in parallel with each other such that the second sub-line has a second characteristic impedance. According to the invention, the second sub-line comprises a plurality of first sub-lines which are mutually connected in parallel, so that the coaxial line structure with the electromagnetic band gap characteristic is formed by using the coaxial line with the same characteristic impedance, the manufacturing cost is lower, and the difficulty and the complexity of circuit realization are greatly reduced. In addition, the invention also unexpectedly realizes a coaxial line structure which can improve the characteristic impedance ratio of the coaxial line, and realizes the phenomena of faster super light speed and slower slow light speed.
Drawings
FIG. 1A is a schematic diagram of a coaxial configuration according to an embodiment of the present invention;
FIG. 1B is a schematic diagram of another coaxial line structure according to an embodiment of the present invention;
FIG. 1C is a schematic diagram of another coaxial line structure according to an embodiment of the present invention;
FIG. 2A is a schematic view of a connector of a coaxial cable structure according to an embodiment of the present invention;
FIG. 2B is a schematic view of another connector of a coaxial cable structure according to an embodiment of the present invention;
FIG. 2C is a schematic view of another connector of a coaxial line structure according to an embodiment of the present invention;
FIG. 2D is a schematic view of another connector of a coaxial cable structure according to an embodiment of the present invention;
FIG. 3 is a test transmission frequency response S21 curve for a coaxial line structure according to an embodiment of the present invention;
FIG. 4A is a schematic diagram of a coaxial configuration according to another embodiment of the present invention;
FIG. 4B is a schematic diagram of another coaxial line according to another embodiment of the present invention;
FIG. 4C is a schematic diagram of another coaxial line according to another embodiment of the present invention;
FIG. 4D is a further coaxial structural schematic of another embodiment of the present invention;
FIG. 4E is a further coaxial structural schematic of another embodiment of the present invention;
FIG. 5A is a schematic diagram of a coaxial configuration of a further embodiment of the present invention;
FIG. 5B is a schematic diagram of another coaxial line structure according to another embodiment of the present invention;
FIG. 5C is a further schematic coaxial structure according to yet another embodiment of the present invention;
FIG. 5D is a further coaxial structural schematic of a further embodiment of the present invention;
FIG. 5E is a schematic diagram of another coaxial line according to yet another embodiment of the present invention;
FIG. 5F is a further coaxial structural schematic of a further embodiment of the present invention;
fig. 6 is a test transmission frequency response S21 curve of a coaxial line structure according to another embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. The invention discloses a coaxial line structure, aiming at solving the technical problems that the structure is difficult to realize and the manufacturing cost is high because a coaxial line structure with electromagnetic band gap characteristics needs to use two coaxial lines with different characteristic impedances in the prior art.
In the invention, coaxial lines are combined to form a coaxial line structure with an electromagnetic band gap. The coaxial line has certain characteristic impedance, and can be classified according to different characteristic impedances.
Specifically, the characteristic impedance of the high-impedance coaxial line with higher characteristic impedance can be preset to be Z0HThe relative dielectric constant of the medium between the inner conductor and the outer conductor of the high-impedance coaxial line is epsilonrH(ii) a In addition, the characteristic impedance of the low-impedance coaxial line with lower characteristic impedance is preset to be Z0LThe relative dielectric constant of the medium between the inner conductor and the outer conductor of the low-impedance coaxial line is epsilonrL. Therefore, for the requirement of low loss of the coaxial line, the phase speeds of the electromagnetic wave transmission on the two coaxial lines respectively satisfy the following formulas (1) and (2):
vH＝c/εrH 0.5
vL＝c/εrL 0.5
where c is the speed of light in vacuum.
Frequency f0The phase wavelengths of the transmission lines corresponding to the electromagnetic waves satisfy the following equations (3) and (4), respectively:
λH＝c/(f0×εrH 0.5)
λL＝c/(f0×εrL 0.5)
wherein λ isHTransmission phase wavelength, lambda, for high impedance coaxial linesLThe transmission phase wavelength of the low impedance coaxial line.
In the embodiment of the invention, the characteristic impedance can be Z0HLength of λHA/4 coaxial line and a characteristic impedance of Z0LLength of λLThe/4 coaxial lines are alternately connected to form a periodic impedance coaxial line structure. The coaxial lines can be connected through a radio frequency microwave connector. The periodic impedance coaxial line structure will be at frequency f0An electromagnetic band gap (i.e., a stop band) is formed nearby and at a frequency f corresponding to the electromagnetic band gap0The nearby area may also generate a super light speed transmission phenomenon.
The group velocity of electromagnetic wave transmission is known to satisfy equation (5):
vG＝dω/dk＝c/(n+ω×dn/dω)
where n is the refractive index related to frequency, and ω ═ 2 π f is the angular frequency.
At frequency f of the electromagnetic band gap0The nearby region has anomalous dispersion characteristic, i.e. dn/d omega<0, and therefore the group velocity v of the electromagnetic wave transmissionGThe speed of light c in vacuum may be exceeded.
As another embodiment of the present invention, if the length of the coaxial line at the center of the periodic impedance coaxial line structure is doubled to make the length of the central coaxial line reach one half wavelength, the original periodic impedance coaxial line structure is destroyed, and a periodic impedance coaxial line structure with defects is formed, that is, a coaxial line structure with part of periodic impedance and part of non-periodic impedance (i.e., with defects) is formed. At this time, the corresponding defected periodic impedance coaxial line structure may have a narrow transmission peak in the electromagnetic bandgap. Has stronger normal dispersion characteristic near the frequency of a transmission peak, dn/d omega>0 and greater, group velocity v of electromagnetic wave transmissionGIt becomes smaller, thereby generating a slow light velocity transmission phenomenon. And the electromagnetic band gap frequency beside the transmission peak still has the phenomenon of ultra-fast transmission.
In the present invention, the phenomenon of super-or slow-speed transmission of the periodic impedance coaxial line structure is related to the characteristic impedance of the two coaxial lines. The larger the characteristic impedance ratio (ratio of high characteristic impedance to low characteristic impedance) of the two coaxial lines, the faster the hyper speed of light and the slower the slow speed of light.
For example, two coaxial lines having characteristic impedances of 50 Ω and 93 Ω are used, respectively, and the characteristic impedance ratio of the two coaxial lines is 1.86. The phase velocity of the electromagnetic wave transmission in the two coaxial lines is 0.66c and 0.85c respectively. Frequency f0The 1/4 phase wavelengths corresponding to the two coaxial lines are 6.19m and 7.97m respectively at 8 MHz. The two coaxial lines are alternately connected by 13 to form a periodic impedance coaxial line structure, and an electromagnetic band gap is formed near 8 MHz. The number of the coaxial lines at the center of the periodic impedance coaxial line structure is increased by one, and the periodic impedance coaxial line structure with defects is formed by 14 coaxial lines in total. This structure achieves an electromagnetic bandgap with a narrow transmission peak around 8 MHz. At the electromagnetic band gap of 9.3MHz, the group velocity of electromagnetic wave pulse transmission reachesAnd 2.3c, the ultra-light speed transmission is realized. At the transmission peak of 7.8MHz, the group velocity of electromagnetic wave pulse transmission is 0.30c, and slow light velocity transmission is realized.
In addition, if two coaxial lines with characteristic impedances of 50 Ω and 75 Ω are used, the characteristic impedance ratio of the two coaxial lines is 1.5. The phase velocity of electromagnetic wave transmission on the two coaxial lines is 0.66c, and the corresponding 1/4 wavelengths of the two coaxial lines are 6.2m when the frequency is 8 MHz. From the relationship between the total length of the periodic impedance coaxial line structure formed by the two coaxial lines and the maximum group velocity of the electromagnetic wave transmission, it can be known that when the total length of the periodic impedance coaxial line structure is 105.4m (which is formed by connecting 17 coaxial lines alternately), the maximum group velocity achieved is 2.196 c.
The invention aims to provide a periodic impedance coaxial line structure with electromagnetic band gap characteristics, which realizes a coaxial line using only one characteristic impedance, and the characteristics of the coaxial line, such as length, are the same, so as to further reduce the difficulty and complexity of circuit realization.
It is another object of the invention to increase the characteristic impedance ratio of the coaxial line, achieving faster hyper-speed and slower slow speed.
The present invention discloses a coaxial line structure, wherein, as shown in fig. 1A-2C and fig. 4A-5E, the coaxial line structure comprises: a plurality of first sub-wires 100 and a plurality of second sub-wires 200, wherein each of the first sub-wires 100 has a first characteristic impedance, the plurality of second sub-wires 200 and the plurality of first sub-wires 100 are spaced apart from each other and are periodically connected, and the second sub-wires 200 include: the plurality of first sub-lines 100 are connected in parallel with each other such that the second sub-line 200 has a second characteristic impedance.
Wherein the first sub-line 100 is a coaxial line having a predetermined characteristic impedance and a predetermined phase wavelength, for example, the first sub-line 100 may be the coaxial line having the characteristic impedance Z0HHas a relative dielectric constant of ∈rHOf high characteristic impedance coaxial line of phase wavelength lambdaHThe above formula (3) may be satisfied, and specifically may have a length λH(ii)/4; alternatively, the first sub-line 100 may have the characteristic impedance Z0LHas a relative dielectric constant of ∈rLThe phase wavelength of the low characteristic impedance coaxial line of (2) may satisfy the above formula (4), and may specifically have a length λL/4. At this time, the first characteristic impedance is the characteristic impedance Z0HOr characteristic impedance Z0L。
In the embodiment of the present invention, the second sub-line 200 is composed of a plurality of first sub-lines 100 connected in parallel with each other, when the characteristic impedance of each first sub-line 100 is Z0HOr Z0LThe characteristic impedance Z of the second sub-line 200HOr ZLSatisfies the following formula (6) or (7):
1/ZH＝N/Z0H
1/ZL＝N/Z0L
where N is the number of first sub-lines 100 that are connected in parallel to form the second sub-line 200. At this time, the second characteristic impedance is the characteristic impedance ZHOr characteristic impedance ZL。
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: and the connecting structure is used for connecting the first sub-line and the second sub-line, wherein the connecting structure is a joint or a microwave power divider. Specifically, a connection structure is required to be provided for connecting the first sub-wire 100 with the second sub-wire 200. Since the first sub-line 100 is a unit composition structure of the second sub-line 200, each first sub-line 100 may have only two terminals, and the number of terminals of the second sub-line 200 is determined by the number of the first sub-lines 100 corresponding to the second sub-line 100 formed by combining the plurality of first sub-lines 100 in parallel. For example, when the second sub-wire 200 has 3 first sub-wires 100 connected in parallel with each other, it may have 6 terminals, and for this, the second sub-wire 200 is connected to the adjacent first sub-wire 100, and the corresponding 1 connection terminal on the side of the first sub-wire 100 is connected to the 3 connection terminals on the corresponding side of the second sub-wire 200. Therefore, the connection structure may be a joint or a microwave power divider to achieve the above-described connection of the first sub-line 100 and the second sub-line 200. Wherein, the connection end can be a BNC male end or a BNC female end.
According to an embodiment of the invention, wherein the joint comprises: the connection end of the multi-way joint, such as a tee joint, a four-way joint and a six-way joint, can also be a BNC female end or a BNC male end. For example, when the second sub-line 200 has 1 first sub-lines 100 connected in parallel, it can be connected to the first sub-lines 100 by using a common one-way joint, as shown in fig. 2A; when the second sub-line 200 has 2 first sub-lines 100 connected in parallel, a three-way joint may be used when the second sub-line is connected to the first sub-line 100, as shown in fig. 2B; when the second sub-line 200 has 3 first sub-lines 100 connected in parallel, it may be connected to the first sub-lines 100 using a four-way joint, as shown in fig. 2C. Therefore, the specific joint type can be designed according to the number N of the first sub-wires 100 connected in parallel with the second sub-wires 200, for example, a six-way joint can also be realized, as shown in fig. 2D.
According to the embodiment of the present invention, the first sub-line 100 has x, the second sub-line 200 has y, wherein the x first sub-lines 100 and the y second sub-lines 200 are connected with each other at intervals to form a coaxial line structure, and x and y satisfy: x is y, x is y-1, or y is x-1. That is, the first sub-line 100 and the second sub-line 200 are alternately connected to form a coaxial line structure having a periodic impedance. Specifically, as shown in fig. 1A, the number x of the first sub-lines 100 is 4, and the number y of the second sub-lines 200 is 4; as shown in fig. 1B, the number x of the first sub-lines 100 is 4, and the number y of the second sub-lines 200 is 3; as shown in fig. 1C, the number x of the first sub-lines 100 is 3, and the number y of the second sub-lines 200 is 4.
The periodic impedance coaxial line structure according to the embodiment of the invention is composed of a coaxial line (i.e. a first sub-line 100) with a specific length and a specific impedance as a unit structure, and specifically is composed of a first sub-line 100 and N (N is more than or equal to 2) second sub-lines 200 formed by connecting the same first sub-lines 100 in parallel. Wherein the length of each first sub-line 100 may be a frequency f0Is one quarter of the phase wavelength of the electromagnetic wave in the first sub-line, i.e. lambdaHA/4 or lambdaL/4。
Let the characteristic impedance of the transmission line (i.e. the coaxial line structure with periodic characteristic impedance in the embodiment of the present invention) be Z0If N (N is more than or equal to 2) parallel first sub-lines 100 have a characteristic impedance of Z0and/N. By parallel connection of a plurality of first sub-wires, periodic impedance can be realizedThe characteristic impedance ratio of each sub-coaxial line in the coaxial line structure (i.e. the characteristic impedance ratio between the first sub-line 100 and the second sub-line 200) is larger and more controllable, so that not only can faster light speed and slower slow light speed be realized, but also accurate control of the faster light speed and slower slow light speed can be easily realized.
In addition, the periodic impedance coaxial line structure can be at a frequency f0An electromagnetic band gap having anomalous dispersion characteristics is formed nearby, and the group velocity of electromagnetic wave transmission may exceed the optical velocity c in vacuum.
As shown in fig. 1C, the periodic impedance coaxial line structure includes 3 first sub-lines 100 where x is 3 and 4 second sub-lines 200 where each second sub-line 200 includes 3 first sub-lines 100 connected in parallel, so that the periodic impedance coaxial line structure includes 15 first sub-lines 100, where each first sub-line 100 may have a length of 5 meters, a characteristic impedance of 50 Ω, and connection ends on both sides are BNC male connectors. Wherein the second sub-line 200 connects the first sub-line 100 in parallel and in connection using a four-way junction with a BNC female. The characteristic impedance of the second sub-line 200 in which the three first sub-lines 100 are connected in parallel is about 16.7 omega. Therefore, the periodic impedance coaxial line structure is formed by alternately connecting the second sub-line 200 with the characteristic impedance of 16.7 omega and the first sub-line 100 with the characteristic impedance of 50 omega, wherein the total length of the periodic impedance coaxial line structure is 35m, the number of the first sub-lines 100 is 7, the number of the second sub-lines 200 is 3, and the number of the second sub-lines 200 is 4. Wherein the phase velocity of electromagnetic wave transmission in the coaxial line structure is about 0.78c, the structure can form an electromagnetic band gap with anomalous dispersion characteristic around about 11.7 MHz. As shown in fig. 3, according to the test transmission frequency response characteristic S21 curve of the periodic impedance coaxial line structure obtained by the test of the network analyzer, an electromagnetic bandgap (stopband) appears in the frequency range of 8MHz to 16MHz, the center frequency of the electromagnetic bandgap is about 11.7MHz, and the minimum group delay around the frequency of 11.7MHz is 35 ns. Since the transmission distance of the electromagnetic wave pulse in the periodic impedance coaxial line structure is 35m, the corresponding transmission speed is 3.33c, namely, the ultra-light speed transmission phenomenon, namely, the faster ultra-light speed is achieved.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: a third sub-line 300, a third sub-line300 includes: the plurality of first sub-lines 100 are connected in series with each other such that the third sub-line 300 has a third characteristic impedance. Specifically, when the characteristic impedance of each first sub-line 100 is Z0HOr Z0LThe characteristic impedance Z of the third sub-line 300H3Or ZL3Satisfies the following formula (8) or (9):
ZH3＝N＇×Z0H
ZL3＝N＇×Z0L
where N' is the number of first sub-lines 100 that are connected in series to form a third sub-line 300. At this time, the third characteristic impedance is the characteristic impedance ZH3Or characteristic impedance ZL3。
At this time, the periodicity of the coaxial line structure of the present invention is destroyed due to the addition of the third sub-line 300, thereby constituting a periodic impedance coaxial line structure with defects. The first sub-line 100 of the periodic impedance coaxial line structure with defects is formed, i.e. the coaxial line structure is still based on the same characteristic impedance. Specifically, a section of the third sub-line 300 is connected in a coaxial line structure in which x first sub-lines 100 and second sub-lines 200 with N (N is more than or equal to 2) first sub-lines 100 connected in parallel are alternately connected. Wherein the length of each first sub-line 100 is the frequency f0Is one quarter of the phase wavelength, i.e. lambda, of the electromagnetic wave in transmission in the coaxial lineHA/4 or lambdaL/4. The third sub-line 300 corresponds to increasing the field of a section of the first sub-line 100 in the periodic impedance coaxial line structure by at least 1 time, thereby enabling the length of the connection of the third sub-line 300 to reach at least one half wavelength (lambda)HA/2 or lambdaL/2), it therefore destroys the periodic impedance coaxial line structure, forming a periodic impedance coaxial line structure with defects.
The periodic impedance coaxial line structure with defects of the invention can be used at the frequency f0An electromagnetic band gap is formed nearby, and a narrow transmission peak occurs in the electromagnetic band gap. Near the electromagnetic bandgap frequency, the group velocity of electromagnetic wave transmission may exceed the speed of light c in vacuum; in addition, near the transmission peak frequency, the group velocity of electromagnetic wave transmission becomes small, and a slow light velocity phenomenon occurs.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: the connection structure for connecting any two of the first sub-line 100, the second sub-line 200 and the third sub-line 300 may specifically refer to fig. 2A to fig. 2D and the related description thereof. Therefore, the third sub-line 300 may also be implemented based on the above-mentioned connection structure, and the specific connection structure includes a joint, and may be generally implemented by a joint device such as a multi-pass joint or a microwave power divider.
According to the embodiment of the present invention, wherein the third sub-line 300 is located at the first position, the second position or the third position of the coaxial line structure, the first position is such that one end of the third sub-line 300 is connected to the first sub-line 100 and the other end is connected to the second sub-line 200, as shown in fig. 4A; the second position is such that one end of the third sub-line 300 is connected to the first sub-line 100 and the other end is the outward connection end of the coaxial line structure, as shown in fig. 4B; or, the second position makes one end of the third sub-line 300 connected to the second sub-line 200, and the other end is an external connection end of the coaxial line structure, as shown in fig. 4C; the third position is such that one end of the third sub-line 300 is connected to the first sub-line 100 and the other end is connected to another first sub-line 100, at this time, the third sub-line 300 is equivalent to a second sub-line 200 at the third position instead of the above-mentioned defect-free periodic characteristic impedance coaxial structure, as shown in fig. 4D; alternatively, the third position is such that one end of the third sub-line 300 is connected to the second sub-line 200 and the other end is connected to another second sub-line 200, in which case the third sub-line 300 corresponds to a first sub-line 100 at the third position instead of the above described defect-free periodic characteristic impedance coaxial structure, as shown in FIG. 4E. It can be seen that the third sub-line 300 has various combination states at the arrangement position in the coaxial line structure with periodic impedance, so that the coaxial line structure of the present invention has various defect combinations in different forms to be adapted to more various application requirements.
As shown in fig. 4E, the coaxial line structure consists of 16 first sub-lines 100 that are 5 meters long, have a characteristic impedance of 50 Ω, and have BNC male stubs at both ends. Specifically, the first sub-line 100 and the second sub-line 200 having 3 first sub-lines 100 connected in parallel are alternately connected. Setting a third sub-line at a third position of the coaxial line structure300, the third sub-line 300 is formed by connecting two first sub-lines 100 in series, which is equivalent to doubling the length of the first sub-line 100 of the periodic impedance coaxial line structure located at the third position, that is, the length of the third sub-line 100 is one half wavelength (that is, λ:)HA/2 or lambdaL/2) to destroy the periodic impedance structure of the coaxial line structure, forming a periodic impedance coaxial line structure with defects. Wherein, three first sub-wires 100 in the second sub-wire 200 are connected in parallel through a four-way joint with a BNC female end, and simultaneously connected with the third sub-wire 300 or the first sub-wire 100. Wherein the characteristic impedance of the second sub-line 200 is about 16.7 omega. Therefore, the periodic impedance coaxial line structure is formed by connecting 8 coaxial lines with characteristic impedance of 16.7 omega and 50 omega respectively in a staggered mode, and the total length is 40 m. The phase velocity of the electromagnetic wave transmission in this coaxial line structure is about 0.78 c. This structure can form an electromagnetic bandgap having anomalous dispersion characteristics in the vicinity of about 11.7MHz, and a narrow transmission peak occurs in the electromagnetic bandgap. As shown in fig. 6, according to the test transmission frequency response characteristic S21 curve of the periodic impedance coaxial line structure embodiment obtained by the test of the network analyzer, an electromagnetic band gap (stop band) appears in the frequency range of 7MHz to 17MHz, and a narrow transmission peak appears in the electromagnetic band gap, and the center frequency of the transmission peak is about 11.7 MHz.
The maximum group delay around the transmission peak frequency of 11.7MHz measured by a network analyzer is 777 ns. Since the transmission distance of the electromagnetic wave pulse in the periodic impedance coaxial line structure is 40m, the corresponding transmission speed is 0.17 c. The minimum group delay at the electromagnetic band gap of about 13.9MHz to the right of the transmission peak is 49ns, and the corresponding transmission speed is 2.72c, i.e. the super-optical speed transmission phenomenon, i.e. the faster super-optical speed, is achieved.
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: a fourth sub-line 400, the fourth sub-line 400 comprising: a plurality of second sub-lines 200 connected in series with each other such that the fourth sub-line 400 has a fourth characteristic impedance. Specifically, when the characteristic impedance of each first sub-line 100 is Z0HOr Z0LThe characteristic impedance Z of the fourth sub-line 400H4Or ZL4Satisfies the following formula (10) or (11))：
ZH4＝N"×ZH＝N N"/Z0H
ZL4＝N"×ZL＝N N"/Z0L
Where N "is the number of second sub-lines 200 connected in series to form the fourth sub-line 400, and N is the number of first sub-lines 100 connected in parallel to form the second sub-line 200. At this time, the fourth characteristic impedance is the characteristic impedance ZH4Or characteristic impedance ZL4。
According to an embodiment of the present invention, wherein the coaxial line structure further comprises: a connection structure for connection between any two of the first sub-line 100, the second sub-line 200, the third sub-line 300 and the fourth sub-line 400. Reference may be made specifically to fig. 2A-2D and their associated description above. Therefore, the fourth sub-line 400 may also be implemented based on the above-mentioned connection structure, and the specific connection structure includes a joint, and may generally be implemented by a joint device such as a multi-pass joint or a microwave power divider.
According to the embodiment of the present invention, wherein the fourth sub-line 400 is located at the first position, the second position or the third position of the coaxial line structure, the first position is such that one end of the fourth sub-line 400 is connected to the first sub-line and the other end is connected to the second sub-line 200, as shown in fig. 5A; the second position is such that one end of the fourth sub-line 400 is connected to the first sub-line 100 and the other end thereof is an external connection end of a coaxial line structure, as shown in fig. 5B; or, the second position is such that one end of the fourth sub-line 400 is connected to the second sub-line 200, and the other end thereof is used as an external connection end of the coaxial line structure, as shown in fig. 5C; a third position such that one end of the fourth sub-line 400 is connected to the first sub-line 100 and the other end is connected to another first sub-line 100, as shown in fig. 5D or fig. 5E; alternatively, the third position is such that one end of the fourth sub-line 400 is connected to the second sub-line 200 and the other end is connected to another second sub-line 200, as shown in fig. 5F. It can be seen that the fourth sub-line 400 has various combination states at the arrangement position in the coaxial line structure with periodic impedance, so that the coaxial line structure of the present invention has various defect combinations in different forms to be adapted to more various application requirements.
With regard to the fourth sub-line 400, the electromagnetic bandgap and the super-speed transmission performance of the fourth sub-line can be referred to the third sub-line 300, and it can be understood that the first sub-line 100 and the second sub-line achieve the same technical effect in combination.
According to the embodiment of the present invention, any two of the first sub-line 100, the second sub-line 200, the third sub-line 300 and the fourth sub-line 400 are connected. In other words, the connection between the third sub-line 300 and the fourth sub-line 400 may also exist in the coaxial line structure formed by alternately connecting the first sub-line 100 and the second sub-line 200 to destroy the periodic characteristic impedance thereof, at this time, the connection forming part between the third sub-line 300 and the fourth sub-line 400 may be equivalent to the fifth sub-line, and the position thereof may be changed correspondingly in the coaxial line structure of the periodic characteristic impedance to achieve different electrical effects, which is not described herein again. Similarly, the third sub-line 300 and the fourth sub-line 400 may be alternately spaced and periodically connected to each other to form a corresponding periodic characteristic impedance coaxial line structure, and at this time, the first sub-line 100 and/or the second sub-line 200 may be added to a specific position of the coaxial line structure to destroy the periodic characteristic impedance thereof, so as to form a corresponding defect. Therefore, the diversity of the coaxial line structure of the invention is further enhanced, so that the application of the coaxial line structure is wider.
The periodic impedance coaxial line structure with the electromagnetic band gap characteristic can be used for researching and teaching the electromagnetic band gap structure, the characteristics of the super-light velocity, the slow-light velocity, the normal dispersion, the anomalous dispersion and the like, can also be used for practical commercial application, and has extremely high commercial value and scientific research value.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A coaxial line structure, comprising:
a plurality of first sub-lines having a first characteristic impedance,
a plurality of second sub-lines spaced apart from and periodically connected to the plurality of first sub-lines,
the first sub-line is a coaxial line, and the second sub-line is composed of a plurality of first sub-lines which are connected in parallel, so that the second sub-line has a second characteristic impedance to form the coaxial line structure with periodic impedance, and the coaxial line structure is used for generating electromagnetic band gap characteristics.
2. The coaxial line structure of claim 1,
the first sub-line has a number x,
the second sub-line has a number y,
wherein x and y satisfy: x is y, x is y-1, or y is x-1, and x and y are positive integers.
3. The coaxial line structure of claim 1, wherein the coaxial line structure further comprises:
a third sub-line composed of a plurality of first sub-lines connected in series with each other such that the third sub-line has a third characteristic impedance.
4. The coaxial line structure of claim 3,
the third sub-line is located at the first position, the second position or the third position of the coaxial line structure,
the first position enables one end of the third sub-line to be connected with the first sub-line, the other end of the third sub-line to be connected with the second sub-line,
the second position enables one end of the third sub-line to be connected with the first sub-line or the second sub-line, and the other end of the third sub-line is an external connecting end of the coaxial line structure;
the third position enables one end of the third sub-line to be connected with the first sub-line, and the other end of the third sub-line to be connected with the other first sub-line; or one end of the third sub-line is connected with the second sub-line, and the other end of the third sub-line is connected with the other second sub-line.
5. The coaxial line structure of claim 1 or 3, further comprising:
a fourth sub-line composed of a plurality of second sub-lines connected in series with each other such that the fourth sub-line has a fourth characteristic impedance;
and any two of the first sub-line, the second sub-line, the third sub-line and the fourth sub-line are connected.
6. The coaxial line structure of claim 5,
the fourth sub-line is positioned at the first position, the second position or the third position of the coaxial line structure;
the first position enables one end of the fourth sub-line to be connected with the first sub-line, the other end of the fourth sub-line to be connected with the second sub-line,
the second position enables one end of the fourth sub-line to be connected with the first sub-line or the second sub-line, and the other end of the fourth sub-line is an external connecting end of the coaxial line structure;
the third position enables one end of the fourth sub-line to be connected with the first sub-line, and the other end of the fourth sub-line to be connected with the other first sub-line; or one end of the fourth sub-line is connected with the second sub-line, and the other end of the fourth sub-line is connected with the other second sub-line.
7. The coaxial line structure of claim 1, wherein the coaxial line structure further comprises:
a connection structure for connection between the first sub-line and the second sub-line.
8. The coaxial line structure of claim 3, further comprising:
and the connecting structure is used for connecting any two of the first sub-line, the second sub-line and the third sub-line.
9. The coaxial line structure of claim 5, further comprising:
and the connecting structure is used for connecting any two of the first sub-line, the second sub-line, the third sub-line and the fourth sub-line.
10. The coaxial line structure according to any one of claims 7-9, wherein the connection structure is a joint or a microwave power divider.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5132645A (en) * | 1989-11-15 | 1992-07-21 | Bernd Mayer | Wide-band branch line coupler |
| CN102522617A (en) * | 2011-12-28 | 2012-06-27 | 上海大学 | Stepped impedance resonator (SIR) coaxial-cavity band-pass filter |
| CN205911398U (en) * | 2016-06-15 | 2017-01-25 | 东莞理工学院 | Coaxial waveguide two dimension electromagnetism band gap structure |
| CN207967263U (en) * | 2018-02-24 | 2018-10-12 | 斯必能通讯器材(上海)有限公司 | A kind of cross-linked coaxial low-pass filter of band |
| CN210129571U (en) * | 2019-06-08 | 2020-03-06 | 扬州江嘉科技有限公司 | Dielectric coaxial low-pass filter with transmission zero |
-
2020
- 2020-05-06 CN CN202010371876.2A patent/CN111489863B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5132645A (en) * | 1989-11-15 | 1992-07-21 | Bernd Mayer | Wide-band branch line coupler |
| CN102522617A (en) * | 2011-12-28 | 2012-06-27 | 上海大学 | Stepped impedance resonator (SIR) coaxial-cavity band-pass filter |
| CN205911398U (en) * | 2016-06-15 | 2017-01-25 | 东莞理工学院 | Coaxial waveguide two dimension electromagnetism band gap structure |
| CN207967263U (en) * | 2018-02-24 | 2018-10-12 | 斯必能通讯器材(上海)有限公司 | A kind of cross-linked coaxial low-pass filter of band |
| CN210129571U (en) * | 2019-06-08 | 2020-03-06 | 扬州江嘉科技有限公司 | Dielectric coaxial low-pass filter with transmission zero |
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